Nd:YAG Documentation
Nd:YAG Documentation
Nd:YAG Documentation
Users Manual
This manual contains information you need in order to safely install, align,
operate, maintain and service your Quanta-Ray Lab-Series pulsed Nd:YAG
laser on a day-to-day basis. Also described is the installation and operation
of the HG harmonic generator and IHS internal harmonic separator. The
system comprises three main elements: the Lab-Series laser head, the
power supply and a table-top controller. (The system can also be controlled
remotely via the front panel RS-232 serial port.) An optional Model WA-1
heat exchanger may also be present.
The Introduction contains a brief description of these three components
and is followed by an important chapter on laser safety. The Lab-Series is a
Class IV laser and, as such, emits laser radiation which can permanently
damage eyes and skin, ignite fires and vaporize substances. Moreover,
focused back-reflections of even a small percentage of its output energy
can destroy expensive internal optical components. This section contains
information about these hazards and offers suggestions on how to safe-
guard against them. To minimize the risk of injury or expensive repairs, be
sure to read this chapterthen carefully follow these instructions. This
chapter also contains information regarding system compliance to CDRH
and CE regulations.
Laser Description contains a short section on laser theory regarding the
Nd:YAG crystal rods that are used in the Lab-Series laser. Also included is
a discussion of the second, third and fourth harmonic laser output gener-
ated by the system. Following this is a more detailed description of the
Lab-Series laser system, concluding with system specifications and outline
drawings.
The next few chapters describe the Lab-Series controls and interconnects,
and guide you through its installation, alignment and operation. The last
part of the manual covers maintenance and service and includes a replace-
ment parts list and a list of world-wide Spectra-Physics service centers you
can call if you need help. Appendix A is a Programming Reference Guide
for those who wish to operate the laser system automatically.
Whereas the Maintenance section contains information you need to keep
your laser clean and operational on a day-to-day basis, Service and
Repair is intended to help you guide your Spectra-Physics field service
engineer to the source of any problems. Do not attempt repairs yourself
while the unit is still under warranty; instead, report all problems to Spectra-
Physics for warranty repair.
iii
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
This product has been tested and found to conform to Directive 89/336/
EEC for electromagnetic Compatibility. Class A compliance was demon-
strated for EN 50081-2:1993 Emissions and EN 50082-1:1992 Immu-
nity as listed in the official Journal of the European Communities. It also
meets the intent of Directive 73/23/EEC for Low Voltage. Class A com-
pliance was demonstrated for EN 61010-1:1993 Safety Requirements for
Electrical Equipment for Measurement, Control and Laboratory use and
EN 60825-1:2001 Radiation Safety for Laser Products. Refer to the CE
Declaration of Conformity statements in Chapter 2.
Should you experience any problems with any equipment purchased from
Spectra-Physics, or you are in need of technical information or support,
please contact Spectra-Physics as described in Customer Service. This
chapter contains a list of world-wide Spectra-Physics service centers you
can call if you need help.
Every effort has been made to ensure that the information in this manual is
accurate. All information in this document is subject to change without
notice. Spectra-Physics makes no representation or warranty, either express
or implied, with respect to this document. In no event will Spectra-Physics
be liable for any direct, indirect, special, incidental or consequential dam-
ages resulting from any defects in this documentation.
Finally, if you encounter any difficulty with the content or style of this
manual, or encounter problems with the laser itself, please let us know. The
last page of this manual is a form to aid in bringing such problems to our
attention.
Thank you for your purchase of Quanta-Ray Spectra-Physics instruments.
iv
CE Environmental Specifications
Environmental Specifications
The environmental conditions under which the laser system will function
are listed below:
Indoor use
Altitude: up to 2000 m
Temperatures: 10 C to 40 C
Maximum relative humidity: 80% non-condensing for temperatures up to
31 C.
Mains supply voltage: do not exceed 10% of the nominal voltage
Insulation category: II
Pollution degree: 2
v
Table of Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
CE Environmental Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
CE Electrical Equipment Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Standard Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
vii
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
viii
Table of Contents
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Type I and II Crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Second Harmonic (types I and II), and Third and Fourth Harmonic Generation . . . . . . . . . . . . . . 7-5
ix
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Notes
List of Figures
Figure 1-1: The Lab-Series Laser Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Figure 1-2: The Lab-Series Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Figure 1-3: The Lab-Series Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Figure 2-1: This CE standard safety warning labels would be appropriate for use as an
entry warning sign (EN 60825-1, ANSI 4.3.10.1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Figure 2-2: Optical Beam Dump, Model BD-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Figure 2-3: Laser Head Emission Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
Figure 2-4: The Lab-Series Power supply Control Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
Figure 2-5: The Lab-Series Power supply Rear Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Figure 2-6: Interlock Switches, Laser Head. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Figure 2-7:Interlock Switch, Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Figure 2-8: CE/CDRH Radiation Control Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
Figure 3-1: Electrons occupy distinct orbitals that are defined by the probability of finding
an electron at a given position, the shape of the orbital being determined by the radial and
angular dependence of the probability. Shown is an s orbital on the left, a p type on the right. 3-2
Figure 3-2: A Typical Four-level Transition Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3
Figure 3-3: Energy Level Scheme for the Nd:YAG Laser Source . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4
Figure 3-4: The Q-switch comprises a polarizer, a quarter-wave polarization rotator, and a
Pockels cell. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5
Figure 3-5: Stable and Unstable Resonator Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6
Figure 3-6: Frequency distribution of longitudinal modes for a single line . . . . . . . . . . . . . . . . . . . . . .3-7
Figure 3-7: Simplified Block Diagram of the Lab-Series electronics. . . . . . . . . . . . . . . . . . . . . . . . . . .3-10
Figure 3-8: Lab-Series Timing Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-11
Figure 3-9: Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-14
Figure 4-1: An isometric view of the internal components of the Lab-series laser head. . . . . . . . . . . .4-1
Figure 4-2: Laser Head Rear Panel Controls and Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Figure 4-3: The Laser Head Side Panel Injection Seeder Controls . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Figure 4-4: Laser Head Emission Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5
Figure 4-5: The Power Supply Front Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
Figure 4-6: The 9-Pin SERIAL COM Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7
Figure 4-7: The Power Supply Rear Connector Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8
Figure 4-8: The Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-9
Figure 4-9: The Main Menu Showing all Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-11
Figure 4-10: The Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-13
Figure 4-11: The Information Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14
Figure 5-1: The location of the autotransformer in the power supply. Taps shown for
operating voltages ranging from 190 to 260 Vac. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2
Figure 5-2: Location of system fuses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2
x
Table of Contents
Figure 5-3: The Lab-series laser head showing connections for the umbilical. . . . . . . . . . . . . . . . . . . 5-3
Figure 5-4: Cooling System Component Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Figure 6-1: The Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Figure 6-2: Burn Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Figure 6-3: The Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Figure 6-4: Burn Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Figure 7-1: HG and Temperature Controller Component Identification. The controller is
located inside the laser head near the HG. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Figure 7-2: Controller shown behind the HG. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Figure 8-1: The various mounting and output options for the Lab-Series laser. . . . . . . . . . . . . . . . . . 8-2
Figure 8-2: Single wavelength: second, third or fourth harmonic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Figure 8-3: Dual wavelength: Second, third or forth harmonic plus the fundamental. . . . . . . . . . . . . . 8-3
Figure 8-4: The IHS dichroic mirrors shown in the normal position. . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Figure 8-5: The IHS Mirror Holder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Figure 8-6: Model BD-6 water-cooled beam dump showing mounting screws. . . . . . . . . . . . . . . . . . . 8-6
Figure 9-1: Lens Tissue Folded for Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Figure 9-2: Cooling system component identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Figure 9-3: Short together posts A and B to prevent shock when servicing the flash lamps. . . . . . . . 9-8
Figure 10-1: Cooling system component identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Figure 10-2: Laser head showing coolant connections on the left. . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
List of Tables
Table 2-1 : Label Translations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Table 3-1 : Power Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Table 3-2 : Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Table 3-3 : Mode and Pulse Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Table 3-4: Beam Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Table 3-5: Service Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Table 4-1: The SERIAL COM Port Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Table 7-1: Controller Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Table 7-2: Summary of Translation Arm Positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Table 7-3: Summary of HG Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Table 10-1: Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7
Table A-1: Status/Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
xi
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
xii
Warning Conventions
The following warnings are used throughout this manual to draw your
attention to situations or procedures that require extra attention. They warn
of hazards to your health, damage to equipment, sensitive procedures, and
exceptional circumstances. All messages are set apart by a thin line above
and below the text as shown here.
Warning! Action may cause electrostatic discharge and cause damage to equip-
ESD ment.
xiii
Standard Units
The following units, abbreviations, and prefixes are used in this Spectra-
Physics manual:
Prefixes
tera 12
(10 ) T deci (10-1) d nano (10-9) n
giga 9
(10 ) G centi -2
(10 ) c pico (10 ) -12
p
mega 6
(10 ) M mill -3
(10 ) m femto (10 ) -15
f
kilo 3
(10 ) k micro -6
(10 ) atto (10 ) -18
a
xv
Unpacking and Inspection
System Components
The following components comprise the Lab-Series pulsed Nd:YAG laser
system:
Nd:YAG laser head
Power supply
Controller
Verify all three components are present. Each component is shipped in a
separate container.
Accessory Kit
Included with the laser system is this manual, a packing slip listing all the
parts shipped, and an accessory kit containing the following items:
US or European (German) power cord for the controller, 2 m
table clamp kit: 4 clamps and hardware
a Bondhus SAE Allen wrench set
a 5/32 in. ball driver
01 SCFH air flow gauge for nitrogen purge
purge hose adaptor couplings
garden hose couplings with in. barbs
spare fuses
xvii
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
alignment pinhole
Infrared card
CD-ROM with GUI software for remote operation from a Windows-
based PC.
xviii
Chapter 1 Introduction
1-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
The Controller
1-2
Introduction
The power supply is water cooled and requires an external source of clean
cooling water. (The optional Model WA-1 water-to-air heat exchanger can
be used for this purpose when plentiful clean water is not available.) For
electrical power, 190250 Vac, 35 A is required for 10 Hz systems, 40 A
for 30 Hz system and 55 A for 50 Hz systems.
Patents
The Quanta-Ray Lab-Series laser systems are manufactured under one or
more of the following U. S. patents:
4,156,209 4,232,276
4,197,513 4.955,725
4,936,932 4,232,272
4,310,808 4,342,113
4,360,925 5,001,716
1-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
1-4
Chapter 2 Laser Safety
2-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
ics
ys
-Ph
tra
pec
S
Operating this laser without due regard for these precautions or in a manner
that does not comply with recommended procedures may be dangerous. At
all times during installation, maintenance or service of your laser, avoid
unnecessary exposure to laser or collateral radiation* that exceeds the
accessible emission limits listed in Performance Standards for Laser Prod-
ucts, United States Code of Federal Regulations, 21CFR1040.10(d).
Follow the instructions contained in this manual to ensure proper installa-
tion and safe operation of your laser.
*
Any electronic product radiation, except laser radiation, emitted by a laser product as a
result of or necessary for the operation of a laser incorporated into that product.
2-2
Laser Safety
Safety Devices
Emission Indicator
When on, the amber lamp on the laser head (Figure 2-3) indicates that
power is being supplied to the laser head and that emission is present or
imminent.
When on, this green LED in the upper left corner of the power supply (Fig-
ure 2-4) indicates that ac power is applied to the system. However, the sys-
tem will not turn on until the interlock keyswitch is also turned on.
COMPUTER
RS232C
SHOTS X100
PWR INTERLOCK LOW LASER Q-SW LAMP ANALOG Q-SW LAMP Q-SW
ON FAULT WATER ID TRIG TRIG STROBE SYNC SYNC ADV SYNC
POWER
0
2-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Indicator NORMAL
OPERATING
MANUFACTURING DATE:
MODEL
S/N
THIS LASER PRODUCT COMPLIES
WITH 21 CFR 1040 AS APPLICABLE
MADE IN U.S.A.
Remote Interlock
RANGE
When on, this LED indicates there is a system interlock fault. Once the
fault is corrected, this light turns off.
This safety interlock connector on the power supply rear panel (Figure 2-5)
provides a means to include an external normally closed safety switch in
the interlock loop that turns off the laser in the event the safety switch is
opened. To use this interlock, remove the jumper plug from the INTERLOCK
connector, and either remove the jumper inside or use a similar connector
without a jumper to wire to a perimeter safety switch. The switch can be
attached to an access door or to other auxiliary safety equipment. Wire the
switch as normally closed so that when the door or safety device is
opened and the switch opens, the power to the laser is immediately turned
off, thus preventing unaware personnel from getting hurt.
The power supply is shipped with a 2-pin shorting jumper plug installed
that defeats (closes) this interlock when it is not used. This jumpered con-
nector or an external safety switch wired to it must be in place in order for
the laser to operate.
POWER Keyswitch
Located in the lower right-hand corner of the power supply control panel
(Figure 2-4), the POWER keyswitch provides interlock safety to prevent
unauthorized personnel from using the Lab-Series system when the key is
turned to the off position and is removed from the switch. Turning the
key to the on position closes the interlock and allows the system to be
energized if all the other interlocks are closed and the circuit breaker switch
is on. If the keyswitch is set to off but the circuit breaker is on, power is still
supplied to the harmonic generator ovens to keep the crystals warm.
2-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Warning! Your Quanta-Ray warranty does not cover damage caused by focused
back-reflections.
2-6
Laser Safety
8 Remote Keyswitch
NORMAL
OPERATING
FUSES
30A/250VAC
MODEL
S/N
SPECTRA-PHYSICS LASERS
P.O. BOX 7013
MT. VIEW, CALIFORNIA 94039-7013
MANUFACTURING DATE:
WA-1
Interlock
10
MADE IN U.S.A.
RANGE INTERFACE
REMOTE
INTERLOCK
Power Breaker
Switch
WATER IN
WATER OUT
Laser Head, Output End Power Supply, Water Supply End Power Supply, Control Panel
7 2
Interlock
Switch
Controller
AUTO
Nd: YAG/1.5J/8ns
Emission
4 3 11 12 5 6 Laser Head, Side View 7
Indicator Quanta-Ray
SIMMER ERROR
VAR LP
LAMP ENERGY FIXED EXT Q-SW EXT
AND INVISIBLE*
SINGLE SHOT INHIBIT OFF ON
LASER RADIATION IS INT
EMITTED FROM THIS APERTURE
*SEE MANUAL
AVOID EXPOSURE
CE Danger Label CDRH Caution Label CDRH Danger Label CDRH Danger Label
(4) Interlock Defeated EMI (5) Interlock Defeated (6) Non-Interlocked (7)
FUSES FUSES
30A/250VAC or 50A/250VAC
SPECTRA-PHYSICS LASERS
P.O. BOX 7013 Spectra-Physics Lasers
1330 TERRA BELLA AVENUE
Fuse Label MT. VIEW, CALIFORNIA 94039-7013 MOUNTAIN VIEW, CALIF. 94043
Battery Replacement Input Voltage Serial Number Label Patent Label (12)
Label (9) Labels (10) CDRH (11)
2-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Label Translations
For safety, the following translations are provided for non-English speak-
ing personnel. The number in parenthesis in the first column corresponds to
the label number listed on the previous page.
Table 2-1: Label Translations
Label # French German Spanish Dutch
Aperture Ouverture Laser - Expo- Austritt von sichtbarer Por esta abertura se Vanuit dit apertuur wordt
Label sition Dangereuse - Un und unsictbarer Laser- emite radiacion laser zichtbare en niet zicht-
(1) Rayonnement laser visi- strahlung; nicht dem visible e invisible; evite bare laser-straling gee-
ble et invisible est emis Strahl aussetzen. la exposicion. miteerd; vermijd
par cette ouverture. blootstellilng.
European Rayonnement Laser vis- Sichtbare und/oder Radiacion Laser visible Zichtbare en niet zicht-
Safety ible et invisible. Expos- unsichtbare Laserstrahl- y/o invisible. Evite que bare laserstraling. Ver-
(4) tion dangereuse de loeil ung. Bestrahlung von los ojos y la piel queden mijd blootstelling van
ou de la peau au Rayon- Aude oder Haut durch expuestos tanto a la huid of oog aan directe
nement direct ou diffus. direkte oder Streustrahl- Radaicion derecta como straling of weerkaatsin-
Laser de classe 4; Nd: ung vermeiden. Laser- a la dispersa. Producto gen. Klasse 4 Laser
YAG/1.5 J/8 ns. classe 4; Nd: YAG/1.5 J/ Laser Clase 4; Nd: YAG/ Produkt; Nd: YAG/1.5 J/
8 ns. 1.5 J/8 ns. 8 ns.
Caution, Attention. Rayonne- Achtung! Sichtbare und Precaucin, radiacin Let op. Zichtbare en
Defeatable ment visible et invisible unsichtbare schdliche peligrosa electromag- onzichtbare gevaarlijke
Interlock dangereux en cas elektromagnetische ntica visible e invisible electromagnetische
(EMI) douverture et lorsque la Strahlung wenn Abdec- con el dispositivo de straling indien geopend
(5) scurit est neutralise. kung geffnet und Sich- seguridad abierto o con en interlock overbrugd.
erheitsverriegelung su indicacin alterada.
berbrckt. Bedienung-
sanleitung beachten!
Danger, Attention. Rayonne- Vorsicht; Austritt von Peligro, al abrir y retirer Gevaar; zichtbare en
Defeatable ment Laser visible et sichtbarer un unsicht- el dispositivo de segu- niet zichtbare laser-
Interlock invisible en cas barer Laserstruhlung, ridad exist radiacion straling wanneer geo-
(6) DOuverture et lorsque wenn Abdeckung geoff- laser visible e invisible; pend en bij uitgeschak-
la securite est neutra- net und Sicherhetiss- evite que los ohos o la elde interlock; Vermijd
lisse; exposition dan- chalter uberbruckt; piel queden expuestos blootstelling van oog of
gereuse de loeil ou de Bestrahlung von Auge tanto a la radiacion huid aan directe stral-
la peau au rayonnement oder Haut durch direkte dircta como a la dis- ing of weerkaatsingen
dirct ou diffus. oder Streustreustrahl- persa. daarvan.
ung vermeiden.
Danger, Attention; Rayonnement Vorsicht; beim Offnen Peligro, Cuando se abre Gevaar; zichtbare en
Non- Laser Visible et Invisi- Austritt von sichtbare existe Radiacion Laser niet zichtbare laser-
Interlocked ble en Cas DOuverture; und unsichtbare Laser- Visible e Invisible; Evite straling wanneer geo-
(7) Exposition Engereuse strahlung; Bestrahlung que los ojos y la piel end; vermijd blootsteling
de LOeil ou de la Peau von Auge oder Haut queden expuestos tanto aan huid of oog aan dis-
au Rayonnement Direct durch direkte oder Streu- a la radaicion directa ecte straling of weer-
ou Diffus. strahlung vermeiden. como a la dispersa. kaatsingen.
Battery Remplacer la pile par le Batterie nur durch gle- Reemplazar la batera Vervang batteryen door
Warning mme modle ou un ichen oder baugleichen con el mismo tipo, o de zelfde, of door de
Label modle quivalent. Se Typ gem Herstelle- equivalente, recomen- fabrikant geadviseerde
(9) dbarasser des piles rangaben ersetzen. Ver- dado por el fabricante. equivalente typen. Voer
usages conformment brauchyte Batterien Pelegro. Deshacerse de de gebruikte battereien
au recommandations du ordnungsgem entsor- las bateras usadas de af volgens de instructies
fabricant. gen. acuerdo con las instruc- van de fabrikant.
ciones del fabricante.
Patent Label Ce produits est fabriqu Dieses Produkt wurde Este producto esta fab- Dit product is gefabri-
(12) sous lun ou plusieurs unter Verwendung einer ricado con una o ms ceerd met een of meer
des brevets suivants. oder mehrerer der fol- de las siguientes pat- van de volgende USA
genden US-Patente entes de los Estados patenten.
hergestellt. Unidos.
2-8
Laser Safety
CE Declaration of Conformity
We,
Spectra-Physics, Inc.
Solid-State Lasers
1330 Terra Bella Avenue
Mountain View, CA. 94043
United States of America
declare under sole responsibility that the:
Quanta-Ray Lab-Series pulsed Nd:YAG laser system with power supply,
analog remote, or pc-based controller running Windows-based GUI
control software,
Manufactured after December 1, 1995,
meets the intent of EMC Directive 89/336/EEC: 1989, for electromagnetic com-
patibility and Directive 73/23/EEC, the Low Voltage directive. Compliance was
demonstrated to the following specifications as listed in the official Journal of
the European Communities:
EMC Directive 89/336/EEC: 1989
EN 50081-2:1993 Emissions:
EN55011 Class A Radiated
EN55011 Class A Conducted
EN 50082-1:1992 Immunity:
IEC 801-2 Electrostatic Discharge
IEC 801-3 RF Radiated
IEC 801-4 Fast Transients
Low Voltage Directive 73/23/EEC: 1973
EN 61010-1: 1993 Safety Requirements for Electrical Equipment for
Measurement, Control and Laboratory use:
EN 60825-1: 2001 Safety for Laser Products.
I, the undersigned, hereby declare that the equipment specified above conforms
to the above Directives and Standards.
Bruce Craig
Vice President and General Manager
Spectra-Physics, Inc.
Solid-State Lasers
January 1, 2003
2-9
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
2-10
Laser Safety
2-11
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
2-12
Chapter 3 Laser Description
h = E2 E1 [1]
*
Light will be used to describe the portion of the electromagnetic spectrum from far
infrared to ultraviolet.
3-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Figure 3-1: Electrons occupy distinct orbitals that are defined by the
probability of finding an electron at a given position, the shape of the
orbital being determined by the radial and angular dependence of the
probability. Shown is an s orbital on the left, a p type on the right.
Likewise, when an atom excited to E2 decays to E1, it loses energy equal to
E2 E1. The atom may decay spontaneously, emitting a photon with energy
h and frequency
E E
2 1 [2]
= -----------------
-
h
Spontaneous decay can also occur without emission of a photon, the lost
energy taking another form, e.g., transfer of kinetic energy by collision
with another atom. An atom excited to E2 can also be stimulated to decay to
E1 by interacting with a photon of frequency , emitting energy in the form
of a pair of photons that are identical to the incident one in phase, fre-
quency, and direction. This is known as stimulated emission. By contrast,
spontaneous emission produces photons that have no directional or phase
relationship with one another.
A laser is designed to take advantage of absorption, and both spontaneous
and stimulated emission phenomena, using them to create conditions favor-
able to light amplification. The following paragraphs describe these condi-
tions.
Population Inversion
The net absorption at a given frequency is the difference between the rates
of emission and absorption at that frequency. It can be shown that the rate
of excitation from E1 to E2 is proportional to both the number of atoms in
the lower level (N1) and the transition probability. Similarly, the rate of
stimulated emission is proportional to the population of the upper level (N2)
and the transition probability. Moreover, the transition probability depends
on the flux of the incident wave and a characteristic of the transition called
its cross section. The absorption coefficient depends only on the differ-
ence between the populations involved, N1 and N2, and the flux of the inci-
dent wave.
3-2
Laser Description
E3 4F 11502 cm-1
3/2
2 1
E2 4I 2111 cm-1
11/2
E1 4I Nd3+
9/2
3-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
20 Pump
Bands
18
16
4F3
14 /2 11502 cm-1 R2
11414 R1
12 4F3 Laser Transition
/2
4I15
Laser /2
10 Transition ~6000 cm-1
8 4I13
/2 ~4000 cm-1
4I15
6 /2
2526
4I13 4I11 2473
/2 /2
4 2146
4I11 2111
2 /2 2029
4I9 4I9 2001
/2 /2
0 848
Ground Level 311
197
134
0
Figure 3-3: Energy Level Scheme for the Nd:YAG Laser Source
The most probable lasing transition is to the I 11/2 state, emitting a photon at
1064 nm. Because electrons in that state quickly relax to the ground state,
its population remains low. Hence, it is easy to build a population inversion.
At room temperature the emission cross section of this transition is high, so
its lasing threshold is low. While there are competing transitions from the
same upper statemost notably at 1319, 1338, and 946 nmall have
lower gain and a higher threshold than the 1064 nm transition. In normal
operation, these factors and wavelength-selective optics limit oscillation to
1064 nm.
A laser comprising just an active medium and resonator will emit a pulse of
laser light each time the flash lamp fires. However, the pulse duration will
be long, about the same as the flash lamp, and its peak power will be low.
When a Q-switch is added to the resonator to shorten the pulse, output peak
power is raised dramatically.
3-4
Laser Description
Q-switching
Because the upper level of the transition has a long lifetime, a large popula-
tion of excited neodymium ions can build up in the YAG rod, much in the
same way a capacitor stores electrical energy. If oscillation is prevented
while the population inversion builds, and if the stored energy can be
quickly released, the laser will emit a short pulse of high intensity light. To
do this, an electro-optic device (a Q-switch) is added to the cavity, which
introduces high cavity loss and prevents oscillation. This allows energy to
build up. It is then quickly switched to a very low loss state that allows
oscillation to occur and the cavity dumps its energy in the form of a light
pulse.
As shown in Figure 3-4, the Q-switch comprises a polarizer, a quarter-wave
plate, and a Pockels cell. A high voltage applied to the Pockels cell crystal
changes its polarization retardation characteristics, which determine
whether the Q-switch is open (low loss) or closed (high loss).
5 s
4 kV
High
Reflector
3-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Unstable
3-6
Laser Description
(DCR) its name. A second form employs a partially reflective coating that
uniformly covers the whole substrate. The third is a variation on the first,
where the small high reflector is replaced by a partial reflector with radially
variable reflectivity (an RVR optic). This reflector is capable of producing
gaussian or near-gaussian spatial profile at the laser output, and is, there-
fore a gaussian coupled resonator, or GCR. This Lab-Series laser uses the
latter variation.
If the energy of the output beam is to be uniformly distributed, the Nd:YAG
rod must be uniformly illuminated. Placing the flash lamp at one focus of
an elliptical chamber causes all the light it produces to be reflected through
the rod, which is placed at the other focus.
Uniform cooling is also essential to optimal performance of pulsed
Nd:YAG lasers. When heated, the Nd:YAG rod becomes a lens whose focal
length depends on the average power absorbed. For optimal performance,
the high reflector must be matched to the focal length of the rod, which
must remain stable during operation. The thermal gradient of the rod also
causes a radially variable polarization rotation that must be carefully con-
trolled for the best beam quality.
3-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
3-8
Laser Description
L = LT [5]
3-9
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Fixed H I
Fixed Q-SW
Repetition Pulse Marx Q-switch
Delay Generator Bank H.V.
Rate
A D
External Q-switch Ext Q-SW K
Input Delay trig input Pulse Q-switch
Generator Sync.
Out
Variable Q-switch
Variable Pulse
Repetition Delay Generator Adv. Sync.
Rate E F Out
J
Pulse Lamp
Generator Sync. Out
Simmer
Current Pulse
Generator
Switching
C Supply
Lamp
3-10
Laser Description
T=0
>500 ns
50 Input
Positive Edge Trigger
2.5 6 V
TTL Compatible A Ext. Lamp Trigger Input
5 ms
50 Input
2.5 V Into 50
TTL Compatible J Lamp Sync Output
FWHM = 180 s
C Lamp Current
500 s Max
60 ms Min
210 s Nom
D Q-Switch Delay
>500 ns
50 Input
Positive Edge Trigger
2.5 6 V
TTL Compatible L Ext. Q-Switch Trigger Input
5 ms
50 Input
2.5 V Into 50 TTL Compatible K Q-Switch Sync Output
6.5 V Into 50
H Marx Bank Trigger
3.5 kV
8 12 ns FWHM
2.5 ns FWHM
3-11
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
3-12
Laser Description
3-13
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Outline Drawing
13.00
330
46.16 5.01 4.00
1172 127 102
12.04
306 7.62
193
30.3 21.2
770 538
17.22
437
19.8
2.5 502
64 25.2
640
Quanta-Ray
SIMMER ERROR
VAR LP
185 SOURCE
INHIBIT OFF
MODE
ON
SINGLE SHOT
INT
Controller
3-14
Chapter 4 Controls, Indicators and Connections
This chapter describes the controls, indicators and connections of the Lab-
Series laser head, power supply, controller and GUI control software. Fig-
ure 4-1 shows the various components inside the Lab-Series laser head.
Injection Seeder
2
1 HG Temperature
Controller
Figure 4-1: An isometric view of the internal components of the Lab-series laser head.
4-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Referring to Figure 4-1, the laser head components are described, starting
from the rear mirror and moving forward.
Rear mirror M1 one of two oscillator cavity end mirrors. It reflects all
laser light back into the cavity. Vertical and horizontal controls allow you to
align the oscillator cavity and to optimize output power and mode quality.
These controls are only accessible when the cover is off.
/4 (quarter-wave) platerotates the polarized cavity light 90 and is
used in conjunction with the polarizer and Pockels cell to set the Q-switch
holdoff, i.e., when properly aligned, there will be no laser oscillation until
the Q-switch is fired, no matter how much oscillator PFN voltage there is
(8 V max.).The waveplate is aligned by rotating the knurled ring around the
high reflector.
Pockels cella high-voltage device (crystal) used as an optical high-speed
shutter to Q-switch pulses. It is opaque (blocks light) until voltage is
applied to it. There are no local controls.
Polarizera coated optic placed in the beam path that allows only polar-
ized light with a select polarization alignment to pass through. It is used in
conjunction with the /4 plate to select light of a certain polarization for
transmission. The polarizer is aligned by rotating the optic in its holder. A
clamping screw holds it in place.
Pump chambers (1 to 2 chambers in one of 2 types)a rectangular box
that contains a single parabolic chamber with a flash lamp placed at one
focus point and a YAG rod at the other, or a dual parabolic chamber with a
flash lamp at the focus of each chamber and the rod placed at the focus
common to each chamber. The YAG rod is the lasing media which is
pumped by the lamp(s).
The number and type of chambers found in the oscillator depends on the
laser model and its output power capacity. There are no controls on the
chambers. Two terminals provide attachment for the high-voltage wires for
the lamp(s).
Marx bankprovides power to drive the Pockels cell and uses a TTL-
trigger source from the power supply controller to turn on and off the cell.
Injection seeder(optional) provides a small amount of single-frequency
laser light of the desired wavelength to stimulate emission at that wave-
length in the oscillator once the proper threshold for lasing is reached in the
rod. Its controls are provided on one of the laser side panels. Refer to Side
Panel later in this chapter for a description of these controls.
Base panencloses the bottom of the laser to keep it clean and to provide
emf and safety shielding.
Output coupler M2 one of two cavity end mirrors. Whereas rear mirror
M1 reflects all light back into the cavity, output coupler M2 allows a small
percentage of it to pass through as the oscillator output laser beam. Its ver-
tical and horizontal controls allow you to align the oscillator cavity and to
optimize output power and mode quality. These controls are only accessi-
ble when the cover is off.
Harmonic generator (HG)contains various crystals that, depending on
their sequence and orientation to the incoming beam, generate second,
4-2
Controls, Indicators and Connections
third and fourth harmonics from the primary wavelength. There are two
control arms for positioning and rotating the optics inside. Refer to Chapter
7, Harmonic Generator, for detailed information on using this device.
HG temperature controllerstabilizes the temperature of the HG crys-
tals, thus maintaining stable output despite changes in ambient tempera-
ture. Refer to Chapter 7, Harmonic Generator, for information describing
the use and setting of these controls.
Dichroic mirror 1 (DM1)reflects certain wavelengths and routes this out-
put to DM2 for transmission while transmitting residual 1064 and/or 532 nm
to the beam dump. Vertical and horizontal controls allow you to adjust the
routing of the beam.
Dichroic mirror 2 (DM2)like DM1, it selects certain wavelengths for
reflection, then routes this output beam out the laser. Vertical and horizon-
tal controls allow you to adjust the routing of the beam.
Beam dump (BD-6) water-cooled, absorbs the residual 1064 nm output.
Aluminum base plateprovides a rigid and thermally stable platform
upon which to mount the laser components.
Q-Switch
Connector
4-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Danger! 5 kV is present at the Marx bank connectors. Shut off the laser (press
the stop button) before changing outputs.
Figure 4-3: The Laser Head Side Panel Injection Seeder Controls
Power ON indicatorglows amber to show the seeder is powered on.
STANDBY/ON switchsets the system to standby (STBY) or active mode
(ON). In standby, all temperature control circuits are operational but the
laser seeder is disabled. In active mode, the seeder is enabled.
Mode switchallows you set the seeder to manual mode (MNL) or auto-
matic mode (AUTO), or to disable it (DSBL). Use the MNL position to set the
piezoelectric voltage to the center of its range. The AUTO position allows a
servo to reset the piezoelectric to its center whenever the piezoelectric volt-
age reaches the end of its range (auto-centering). DISABLE prevents the
servo from resetting the system automatically.
4-4
Controls, Indicators and Connections
4-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
COMPUTER
RS232C
SHOTS X100
PWR INTERLOCK LOW LASER Q-SW LAMP ANALOG Q-SW LAMP Q-SW
ON FAULT WATER ID TRIG TRIG STROBE SYNC SYNC ADV SYNC
POWER
0
4-6
Controls, Indicators and Connections
6 9
*
Windows is a registered trademark of the Microsoft corporation.
4-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Indicator NORMAL
OPERATING
MANUFACTURING DATE:
MODEL
S/N
THIS LASER PRODUCT COMPLIES
WITH 21 CFR 1040 AS APPLICABLE
MADE IN U.S.A.
Remote Interlock
RANGE
4-8
Controls, Indicators and Connections
The Controller
The controller plugs into the 37-pin REMOTE connector on the power sup-
ply. Its controls and indicators are shown in Figure 4-8 and are listed and
described here from top to bottom, left to right.
OSCillator SIMMER indicatorglows whenever the oscillator flash lamp
simmer current is on.
AMPlifier SIMMER indicator (is not used on the Lab-Series system)
OSCillator LAMP ENERGY controlsets the output energy of the oscilla-
tor flash lamp(s). The scale is relative and is marked START 10.
AMPlifier LAMP ENERGY control(is not used on the Lab-Series system)
Quanta-Ray
SIMMER ERROR
VAR LP
LAMP ENERGY FIXED EXT Q-SW EXT
SOURCE MODE
INT
4-9
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Rep Rate VARIABLE controlsets the lamp firing rate in a range that is
approximately 1 Hz to +5% from the system fundamental FIXED frequency
setting as denoted by the laser model number.
Q-SWITCH ERROR indicatorblinks if the remote control source has
selected more than one mode to trigger the Q-switch.
Q-SWitch DELAY controladjusts the Q-switch firing delay timing from
50 to 300 s.
Rep Rate SOURCE selectorselects the source of the lamp firing pulse:
FIXED, VARIABLE, or EXTernal source. FIXED selects the repetition rate as
denoted by the laser model number. VARIABLE allows you to vary the pulse
rate from approximately 1 Hz to +5% of the system fixed frequency. The
EXTERNAL setting requires a firing pulse to be presented at the LAMP TRIG
input on the power supply, but is constrained by the same limitations of the
VARIABLE setting. Do not exceed this rating.
Q-switch MODE selectorselects the source for the timing of the Pockels
cell firing: Q-SW, LP and EXT. When set to Q-SW, the Pockels cell is fired
after the flash lamps with a time delay set by the Q-SW DELAY control (see
above). When set to LP (Long Pulse), the Pockels cell and flash lamp are
fired synchronously. When set to EXT (external), the Pockels cell is fired by
a signal presented at the power supply Q-SW TRIG input.
Note Be careful when using the Q-switch MODE selector that the Q-switch
DELAY setting above it is not disturbed, since laser output power is sen-
sitive to the DELAY setting.
Main Menu
This is the first menu that appears when the software is started. It will
remember the controls that were present the last time the program was
used.
INTERLOCK fault indicatorturns on whenever an interlock fault has
occurred. To clear the fault, turn off the laser (press the ON/OFF button), fix
the fault (refer to the MONITOR lamps on the power supply), then turn the
laser on again.
ADVANCED SYNC controladjusts the output sync signal from 700 ns
before Q-switch firing to 500 ns after it fires to allow synchronizing to aux-
4-11
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
iliary equipment. This signal is available at the Q-SW ADV SYNC output
connector on the power supply.
QSWITCH selectorselects the source for the timing of the Pockels cell
firing.
NORMAL (Q-switched)the Pockels cell is fired after the flash lamps
with a time delay set by the Q-SW DELAY control on the Setup menu.
LONG PULSE the Pockels cell and flash lamp are fired synchro-
nously.
EXTERNAL the Pockels cell is fired by a signal presented at the
power supply Q-SW TRIG input.
EMISSION indicatorwhen the laser is on or capable of emitting laser
light, Emission is displayed in black letters on a red background, warn-
ing that laser output is available or imminent.
PUMPS indicatorwhen on, indicates the pump is on and system has
pressure. If this lamp turns off, either the pump has failed, the reservoir is
low on fluid or there is a blockage or kink in the coolant line.
SIMMER indicator glows whenever the oscillator flash lamp simmer cur-
rent is on and turns off if simmer current is not available.
HIGH VOLTAGE indicatorwhen on, indicates the high-voltage circuits
are working properly; when off, the high-voltage system is not on yet or
has failed.
ON/OFF switchtoggles the laser on and off. When the button has been
pushed to turn on the laser, the button turns green. Otherwise, the button is
gray when the laser is off.
REPETITIVE/SINGLE/FIRE slide controlprovides a means to set the laser
system to repetitive pulse mode or single shot mode, and to fire single shots
at will. To select the desired mode, click on the lever and slide it to that
position. To fire single shots, click on the lever while it is in the single-shot
position.
REPETITIVE this position fires the lamps automatically at a rate set
by either the VAR RATE control or the source selected using the LAMPS
TRIGGER selector.
SINGLE this position takes the system out of repetitive pulse mode
and allows the operator to fire the lamps one pulse at time.
FIRE fires the lamp(s) a single time when the lever is pressed. Actual
firing is synchronized to the next pulse from the selected lamp trigger
source.
VAR RATE controlsets the lamp firing rate in a range that is approxi-
mately 1 Hz to +5% above the system fundamental FIXED frequency set-
ting as denoted by the laser model number.
LAMPS TRIGGER selectorinhibits firing or selects the source of the lamp
firing pulse.
INHIBIT prevents the lamps from firing.
FIXED sets the repetition rate to that denoted by the laser model num-
ber.
4-12
Controls, Indicators and Connections
Setting Menu
Information Menu
4-13
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
4-14
Chapter 5 Installation and Alignment
Warning! Purge the laser with dry nitrogen only or you will void your warranty!
1. Place the laser head on a suitable optical table and place the controller
near it.
2. Place the power supply on the floor within 3 m (10 ft) of the facility
power source (the length of the power cord) and within 3 m of the laser
head (the length of the umbilical).
Caution! The air vents on the power supply provide cooling for components
inside. These vents are strategically placed for air flow management.
Allow about 0.5 m (2 ft) clearance around the power supply for proper
air movement.
3. Loosen the two screws on each side of the power supply and carefully
lift off the cover.
5-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Main Fuses
5-2
Installation and Alignment
Figure 5-3: The Lab-series laser head showing connections for the
umbilical.
1. Connect the three large electrical connectors by pushing them in, then
screwing on the outer shell.
2. Connect the input to the nitrogen purge flow regulator (included in the
accessory kit) to the dry nitrogen tank.
You need to supply the hose fittings for attaching the regulator hose to
your nitrogen supply.
3. Connect the flow regulator output hose to the purge input port on the
laser head.
Simply push the hose fitting in until it clicks. To remove the hose, push
in on the retaining wire clip and pull the hose out.
4. Connect the Q-switch BNC control cable to the laser head panel.
5. Connect the two coolant water hoses to the laser head connector panel.
The hoses are polarized. Simply push the hoses on until they click. to
remove a hose, push on the metal retaining tab and pull the hose out.
Be careful of water spillage when removing hoses.
This completes the procedure to connect the power supply to the laser head.
5-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Warning! To prevent damage caused by freezing, the laser cooling system was
drained before initial shipment. The system must be filled with water
before operating the laser for the first time. Your Spectra-Physics ser-
vice representative will perform this task during initial installation.
Before he arrives, obtain 20 l (5 gal) of distilled water for filling and
flushing the system.
During the following process, water will have to be added to the reservoir
in the power supply (Figure 5-4) several times as the system fills. Rather
than remove and replace the reservoir cover several times, it is easier to use
a long-necked funnel placed in the return hose entry of the reservoir cover
to add water as needed.
Level Sensor
Return Hose
Deionizing Filter
Reservoir
Particle Filter
Cooling Pump
Warning! Avoid spilling water on any electrical components. When power is reap-
plied, some components will contain high voltage and damage can
occur. If you do spill water, clean it up immediately.
Control Setting
Circuit breaker (power supply) Closed
Keyswitch (power supply) ON
LAMP ON switch (controller) OFF (INHIBIT light is on)
5-4
Installation and Alignment
5-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Alignment
Danger! Your Lab-Series laser was aligned at the factory by specially trained
professionals and again when it was first set up at your site. It should not
require further alignment in the field. Furthermore, the laser contains
lethal high voltage and generates an enormous amount of optical power
that can cause damage and even injury. Therefore, do not attempt to
align the laser yourself, you may void your warranty. Instead, call your
Spectra-Physics service representative.
5-6
Chapter 6 Operation
The Lab-Series Nd:YAG laser system is controlled locally using the table-
top controller provided with the system. It can be controlled remotely via
the 9-pin RS-232 serial port on the power supply using the Windows*-
based software provided with the system. It emulates the controller func-
tions on a computer. It also can be controlled remotely using your own soft-
ware program running on a computer. Appendix B, Programming
Reference Guide, explains the Lab-Series RS-232 command language and
how it is used to control the laser system. (Note: an optional IEEE-488 port
is also available for remote control of the system.)
Chapter 5 explains how to connect the system and explains how to install
the Lab-Series GUI software. This chapter assumes this has already been
done if you are going to use it.
This chapter is divided into two major sections. The first describes laser
operation using the provided local controller. The second describes laser
operation using the GUI software provided. The
Quanta-Ray
SIMMER ERROR
VAR LP
LAMP ENERGY FIXED EXT Q-SW EXT
SOURCE MODE
INT
*
Windows is a registered trademark of the Microsoft Corporation
6-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Control Setting
OSC LAMP ENERGY knob START
SOURCE switch FIXED
MODE switch Q-SW
INT/COMPUTER switch INT
SINGLE SHOT/REP switch REP
LAMP ON switch Lamp on (INHIBIT lamp is off)
Q-SWitch DELAY knob mid-range
Standard Operation
Start-up
For day to day operation after you have some experience operating this sys-
tem, you may want to use the Quick Start/Stop Procedures above to save
time. The following detailed procedures are provided for those who are not
familiar with the system.
1. Set the controller as follows:
Control Setting
Oscillator (OSC) LAMP ENERGY knob START
Rep rate SOURCE switch FIXED
Q-SWitch MODE switch Q-SW
6-2
Operation
Control Setting
INT/COMPUTER switch INT
SINGLE SHOT/REP switch SINGLE SHOT
LAMP ON switch Lamp on (INHIBIT lamp is off)
2. Verify the power supply POWER circuit breaker is open (off), then
apply utility power to the system.
3. Close the power supply POWER circuit breaker.
4. Turn on POWER key switch.
5. Press the ENABLE button.
6. When the simmer light turns on, turn the OSC LAMP ENERGY knob to
position 7.
Danger! In the following step, do not look at the film when taking a burn pattern.
Laser Radiation The light will be very bright.
7. Obtain a burn pattern to check for proper alignment and any optical
damage.
a. Place a piece of unexposed but developed Polaroid film into a
transparent plastic bag, then place it in the beam path about 1 m
from the laser.
b. Press the SINGLE SHOT: FIRE button once.
8. If the burn pattern is symmetrical (Figure 6-2), set the MODE switch to
Q-SW and adjust the Q-SW DELAY control for maximum output energy.
You can safely raise the LAMP ENERGY control to maximum and
increase the repetition rate by setting the SOURCE switch to VARiable
and increasing the rate to the level desired.
6-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Interlock Faults
An interlock fault shuts off the laser to minimize the risk of damage to sys-
tem components. This is either caused by something that has failed, or
there is a possibility of laser radiation exposure. Interlocks include: water
flow sensor, auxiliary interlock connector, laser head water temperature
sensor, power supply cover switch, and laser head cover switches. Also
included in the interlock chain are the cables to the power supply Control
pc board and Power pc board (both inside the power supply), the controller
and the laser head. When a fault occurs, the interlock fault MONITOR lamps
on the power supply glow.
Note It is normal for the INTERLOCK FAULT indicator to glow when the circuit
breaker and key switch are on but the laser is off because there is no
cooling water flow. Press the ENABLE button to start the coolant pump
and clear the fault.
6-4
Operation
4. Turn off the external cooling water supply (or the heat exchanger if one
is used).
5. Do not turn off the purge supply.
Let it flow 24 hours a day at 2 scfm.
This completes the shut down procedure using the controller.
Control Setting
LAMPS TRIGGER knob FIXED
QSWITCH knob NORMAL
INT/COMPUTER switch (on controller if COMPUTER
plugged into the power supply)
Single shot/rep switch REPETITIVE
Q-SWITCH DELAY knob (on Setup menu) mid-range
6-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
4. Verify the laser head and power supply covers are on.
5. Click on the ON/OFF button to start the cooling pump and start the laser.
6. Once the system is at full power, adjust the Q-SWITCH DELAY knob
until energy output is at its max.
Shut-down
1. Press the ON/OFF button.
2. Once the laser has turned off, allow the water to flow for an additional
5 to 10 minutes to cool down the lamp(s) and rod(s). Proper cool-
down is important for long lamp and rod life!
3. Turn off the external cooling water supply (or the heat exchanger if one
is used).
Standard Operation
Start-up
For day-to-day operation after you have gained some experience operating
this system, use the Quick Start/Stop Procedures above to save time. The
following detailed procedures are provided in the event you are not yet
familiar with the system.
1. Set the controller as follows:
Control Setting
LAMPS TRIGGER knob FIXED
QSWITCH knob NORMAL
INT/COMPUTER switch (on controller if COMPUTER
plugged into the power supply)
Single shot/rep switch SINGLE
Q-SWITCH DELAY knob (on Setup menu) mid-range
2. Verify the power supply POWER circuit breaker is open (off), then
apply utility power to the system.
3. Close the power supply POWER circuit breaker.
4. Turn on POWER key switch.
5. Click on the ON/OFF button.
Danger! In the following step, do not look at the film when taking a burn pattern.
Laser Radiation The light will be very bright.
6. Obtain a burn pattern to check for proper alignment and any optical
damage.
a. Place a piece of unexposed but developed Polaroid film into a
transparent plastic bag, then place it in the beam path about 1 m
from the laser.
b. Press the FIRE button once.
6-6
Operation
7. If the burn pattern is symmetrical (Figure 6-4), set the QSWITCH knob
to NORMAL and adjust the Q-SW DELAY control for maximum output
energy. You can safely increase the repetition rate by setting the
LAMPS TRIGGER switch to VARIABLE and increasing the rate to the
level desired.
Interlock Faults
If an interlock fault is detected, the laser shuts off to minimize the risk of
damage to system components. Such a fault is caused either by something
that has failed or a condition where there is a possibility of laser radiation
exposure. Interlocks include: water flow sensor, auxiliary interlock connec-
tor (for a user-installed switch), laser head water temperature sensor, power
supply cover switch, and laser head cover switches. Also included in the
interlock chain are the signal cables to the power supply Control and Power
pc boards, the controller and the laser head. When a fault occurs, the inter-
lock fault MONITOR lamps on the power supply glow.
Note It is normal for the power supply INTERLOCK indicator to glow when the
circuit breaker and key switch on the power supply are on and the laser
is off because there is no cooling water flow. Click on the ON/OFF but-
ton to start the coolant pump and start the laser.
6-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
2. Once resolved, press the ON/OFF button to clear the fault and start the
laser. If multiple faults have occurred, the system will refuse to start
and a second pop-up window will appear. When all faults have been
resolved, press the ON/OFF button to clear the final fault and start the
laser
Single-Shot Operation
Single-shot operation is typically only used for setup and test. Otherwise
the system is set to repetitive mode.
Shut-down
The laser can be damaged if it is not shut down properly. When finished
using the laser, perform the following steps in the order presented.
1. Click on the on/off button to turn off the laser.
2. Allow the water to flow for an additional 5 to 10 minutes to cool down
the lamp(s) and rod(s). Proper cool-down is important for long lamp
and rod life!
3. Turn off the key switch on the power supply, and turn off the circuit
breaker.
4. Turn off the external cooling water supply (or the heat exchanger if one
is used).
5. Do not turn off the purge supply.
Let it flow 24 hours a day at 2 scfm.
Warning! Make sure that, before shipping the laser or the power supply, the cool-
ant is completely drained from each. The temperature in an aircraft
cargo hold can freeze the coolant and can cause several components to
burst. Such damage is not covered under your warranty!
6-8
Chapter 7 Harmonic Generator
Warning! The harmonic generator (HG) uses KD*P crystals. These crystals are
sensitive to thermal shock, so change temperatures slowly. They are also
hygroscopic, i.e., they are water soluble. Avoid getting them wet, and
keep the humidity in their environment low. To ensure a low-humidity
environment, it is recommended the power supply circuit breaker be left
on even when the other equipment is turned off (including the power
supply keyswitch) so that the HG heater remains on. This also dramati-
cally reduces warm-up time when the system is used the next time.
HG TEMPERATURE CONTROLLER
Power ON LED
ON SHG THG/FHG ON
7-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Angle tuning knob (one for each tuning arm)adjusts the angle of the
crystal for the most efficient harmonic generation, optically aligning it with
the input beam.
Main housingrotates about the optical axis to change the polarization
for different harmonic crystals. The output polarization is always vertical.
Clamping screws lock the HG in the desired orientation.
7-2
Harmonic Generator
Warning! Never move the crystal into or out of the beam while the laser is run-
ning.
7-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
4. Place the HG so that the four elongated holes on its yoke line up with
the corresponding threaded holes in the base plate. Start all four
mounting screws, but leave them loose to allow horizontal movement
of the HG.
5. Slide both crystal translation arms to the 0 position (pushed all the
way in: note the markings on the arm) to move the crystals out of the
beam path.
6. Start the laser, then set controls on the controller as follows (do not use
the GUI interface during this installation):
Table 7-1: Controller Settings
Control Setting
LAMP ENERGY Near threshold
Q-SW DELAY Optimum
SOURCE FIXED
MODE Long Pulse
INT-COMPUTER switch INTernal
SINGLE SHOT switch REPetitive
LAMP ON switch OFF (INHIBIT light is on)
Danger! Use protective eyewear throughout the rest of this procedure. Make all
Laser Radiation adjustments with the laser near the lasing threshold and in Long Pulse
mode.
7. Adjust the HG horizontally and vertically to center the input and exit
windows on the laser beam. Reduce the ambient light in the room and
use an infrared (IR) card as a detector for the input beam. If the HG
must be moved vertically more than its spring-loaded screws allow,
walk the vertical adjustment by simultaneously loosening one
spring-loaded screw and tightening the vertical adjustment screw next
to it. Repeat with the other vertical adjustments.
8. Connect the purge system to the HG and purge for 15 minutes before
proceeding.
9. Check for clipping of the output beam (use an IR card.) Adjust the
base plate of the HG if the crystal clips the beam. Turn the HG to the
other polarization orientation and check again for clipping.
Note The rate of rotation of the beam polarization is twice that of the polar-
ization rotator.
7-4
Harmonic Generator
Operation
1. Verify purge flow is set to 0.5 SCFH, and purge the system for 15 min-
utes before proceeding.
2. Set the crystal translation arms for the wavelength of interest (refer to
Table 7-2 and Table 7-3 at the end of this chapter for arm settings).
Example: to obtain the second harmonic from a type I SHG crystal:
a. Slide the first stage crystal translation arm to I, which places the
type I crystal in the beam path.
b. Slide the second stage crystal translation arm to O, which moves
the second stage crystals out of the beam path.
3. Turn the main housing on its yoke to orient the output for vertical
polarization (it should always be vertical).
Example: to obtain vertically polarized second harmonic output, turn
the main housing on its yoke until the first stage translation arm is ver-
tical. This orients the axis of rotation horizontally for tuning the crystal.
4. Switch to Q-SWitch mode, then angle-tune the crystal for maximum
output at the wavelength of interest.
5. Adjust the polarization rotator for maximum output.
7-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
If either lamp turns off and stays off, turn the associated INC TEMP
control clockwise to increase the temperature a little. The lamp should
turn on, glow continuously for a short time, and blink after that.
If either lamp continues to glow after 10 minutes of operation, turn the
associated INC TEMP pot counterclockwise just until the lamp shuts
off. It should stay off for a short time and blink after that.
5. The fourth harmonic crystal is temperature dependent. In addition to
generating UV, it also absorbs IR. When too warm, it approaches its
critical phase-matching angle and output power will diminish. At this
point, either reduce the input power or turn off the SHG channel heater
and let the crystal cool off.
In the tables below, find the combination of wavelength, polarization, and
SHG crystal for the output of interest on the left-hand side of the table and
set the HG as described on the right-hand side. All output wavelengths are
collinear; they can be separated by dichroic beam splitters or dispersive
prisms (or equivalent optics).
Note It is easy to determine the polarization plane of the last harmonic gener-
ated by the HG. It is in the same plane as (in-line with) the long control
arm that is associated with the crystal generating that harmonic.
7-6
Harmonic Generator
Caution! The table below provides both vertical and horizontal polarization
options available from your HG unit. The IHS dichroics have been opti-
mized for vertical polarization.
7-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
7-8
Chapter 8 Internal Harmonic Separator
Warning! The internal harmonic separator (IHS) transmits and modifies Class IV-
High Power Laser beams. These beams are eye, skin, and fire hazards;
therefore, take precautions to prevent accidental exposure to both direct
and reflected beams. Diffuse as well as specular reflections can cause
severe eye or skin damage.
Dichroics
Dichroic mirrors are used to separate the second, third and fourth harmonic
from the Nd:YAG fundamental in the Lab-Series laser. The small amount
of unwanted harmonics in the beam is regarded as inconsequential for OPO
operation, and the convenience and flexibility of dichroic separation when
used in other applications has led to the creation of the internal dichroic
harmonic separator for general-purpose use.
Dichroic mirrors are characterized by high reflectivity at one range of
wavelengths and low reflectivity elsewhere. Advanced optical coating tech-
niques now allow excellent color separation with high damage thresholds,
even into the ultraviolet (UV).
8-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
System Configurations
The modularity of the IHS allows several system configurations by using a
combination of the optics sets listed above to provide selected output. The
more common configurations are shown in Figure 8-1 to Figure 8-3. Two
windows in the front bezel on 4 in. standard Quanta-Ray spacing provide
selected wavelength output. Figure 8-1 shows the possible placement of
these optics. Some configurations require the removal of the beam dump
(refer to Removing the Beam Dump below).
Laser Head
4 in.
HG Beam Dump
Figure 8-1: The various mounting and output options for the Lab-
Series laser.
Single wavelengthfor second, third or fourth harmonic only, use the IHS-
532 or IHS-266 or IHS-355 as shown in Figure 8-2.
Laser Head
4 in.
HG Beam Dump
8-2
Internal Harmonic Separator
Laser Head
4 in.
1064 nm
HG Beam Dump WP4
Removed
Figure 8-3: Dual wavelength: Second, third or forth harmonic plus the
fundamental.
Danger! During installation, always operate the Nd:YAG laser at low levels to
prevent injury to yourself or damage to the system or both. To pump
with the second harmonic, the low level setting should be un-Q-
switched. The same conditions apply to the third and fourth harmonic,
except that a UV fluorescent card can be used to detect the beam. Safety
goggles or glasses are required any time the laser is on, even at low
energy.
8-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
HG Temperature Controller
Harmonic
Generator
Aluminum
Base Plate
Beam Dump
Figure 8-4: The IHS dichroic mirrors shown in the normal position.
1. Remove the laser head cover (4 screws) and install the shortest wave-
length dichroics at this time.
2. Install the optic mounts in the desired location (refer to Figure 8-1
through Figure 8-3). Use two screws to fasten the mount to the base
plate.
3. Put a power meter or beam dump at the output ports to be used.
4. Turn on the laser in Long Pulse mode.
5. Adjust the dichroic mirror mounts vertically and horizontally to center
the harmonic beam on the selected output port.
6. If you want to use additional second-harmonic dichroics, turn off the
laser and install them along with the required wave plates (WP-3 or
WP-4). Turn on the laser and set it to a safe power level again.
7. Check the alignment of the second harmonic beam and wave plates.
8. Verify the harmonic generator is set so that the shortest harmonic is
vertically polarized (refer to Chapter 7).
9. Turn off the laser.
10. Install the appropriate windows and absorption filters in the beam
paths as required, or enclose the beam path in dust tubes.
11. Replace the cover.
This completes the installation procedure.
8-4
Internal Harmonic Separator
Adjustments
Horiz. Vert.
Mirror Mount
Ring
Mounting Holes
8-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
10-32 Base
Mounting Screw
8-6
Chapter 9 Maintenance
Preventive Maintenance
The top cover of the Lab-Series laser protects the internal components
from outside contamination and also prevents unwanted stray optical
radiation from escaping the system. Always operate the unit with the
top cover in place.
Inspect daily all windows for contamination or damage. The windows
should be cleaned with acetone and lens tissue any time contamination
is suspected or observed. Damaged windows should be immediately
replace.
It is highly recommended that you annually check the safety features
of the laser to ensure safety is maintained (see Chapter 2, Laser
Safety, for details).
9-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Equipment Required
Dry nitrogen, canned air or rubber squeeze bulb
Photographic lens tissue
Spectroscopic grade methanol
Forceps
Hemostat
9-2
Maintenance
Warning! Always follow the instructions in Chapter 6, Operation, for turning off
the laser. Ignoring the shutdown procedure can permanently damage the
lamps and/or rods.
Level Sensor
Return Hose
Deionizing Filter
Reservoir
Particle Filter
Cooling Pump
Danger! Be wary every time you remove the power supply cover that there is
lethal high voltage inside.
1. Circulate water through the system for 30 minutes every week when
the laser is not in use.
9-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Warning! It is important that you follow this instruction for the well-being of your
system. Failure to do so can cause sediment build-up and restricted cool-
ing.
2. Inspect the water level in the reservoir through the window in the
power supply rear panel every time you use the laser.
Keep the reservoir at least half full. Drain the coolant and replace it
with fresh deionized, water every three months.
3. Check the deionizing filter (Figure 9-2) monthly and replace the filter
when all the yellow resin in it has changed color to light brown.
Refer to Replacing the Deionizing Water Filter later in this chapter.
4. Replace the particulate filter whenever you replace the deionizing filter.
Refer to Replacing the Particulate Filter later in this chapter.
5. Replace the air filter monthly or when the blue indicator turns pink.
Warning! Do not attempt to clean, remove, replace or add crystals. Allow only fac-
tory-trained service engineers to open your harmonic generator (HG).
Tools needed:
5
/32 in. Allen (hex) wrench
Small cork for plugging end of cartridge
Small bucket
An absorbent towel
9-4
Maintenance
Procedure
1. Loosen the two screws on each side of the power supply, and lift off
the cover.
2. Remove the T Clip-Lok fitting from the top of the filter cartridge,
and allow the water in the filter to drain back into the reservoir. This
may take several minutes.
3. Place a towel under the bottom T fitting to catch any water that may
leak from the hose or cartridge when the lower fitting is removed.
4. Remove the T Clip-Lok fitting from the bottom of the filter car-
tridge, and place the cork in the now vacant hole on the T fitting.
Allow the remaining water in the filter to drain into the absorbent
towel.
5. Loosen the two 5/32 in. screws located on the filter restraint structure
and remove the filter. Place the filter in the bucket.
6. Place the new filter cartridge in the restraint structure and tighten the
screws.
7. Install both T fittings onto the new cartridge and verify they seal
properly.
8. Clean up any spilled water.
9. Turn on the power supply circuit breaker and key switch, and press the
ENABLE button on the controller to start the pump.
If the pump does not prime itself, prime it by removing the large sup-
ply hose from the reservoir and, using a long-necked funnel, pouring
water into the hose.
10. Run the pump for about 10 minutes.
11. If the MONITOR: LOW WATER indicator lights, shut off the power sup-
ply and add deionized water to the reservoir.
Refer to Chapter 5, Installation and Alignment: Filling the Cooling
System.
12. Replace the power supply cover.
13. Dispose of the used filter cartridge properly.
This completes the procedure for replacing the deionizing filter. Continue
with Replacing the Particle Filter below.
9-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Tools needed:
Wire cutters
Needle-nose pliers
Procedure
1. Loosen the two clamping screws on each side of the power supply, and
lift off the cover.
2. Locate the opaque plastic particulate filter next to the deionizing filter
on the upper tray.
3. Remove the output hose from the reservoir.
4. Remove the input hose where it is attached to the Clip-Lok fitting on
the deionizing filter.
5. Cut the two tie-wraps holding the existing filter in place with the wire
cutters, and discard the tie-wraps.
6. Thread the new tie-wraps through the fasteners.
7. Note the orientation of the existing filter, then replace it with the new
one so the new filter is oriented in the same direction.
8. Place the long output hose into the reservoir.
9. Attach the remaining hose to the Clip-Lok fitting, and verify it is
securely seated.
10. Using the needle-nose pliers, tighten the tie-wraps around the filter so
it is securely fastened to the tray.
11. Install the power supply cover.
This completes the procedure for replacing the cooling system particle filter.
9-6
Maintenance
Tools needed:
Wire cutters
Procedure
1. Verify the system is off and that there is no power to the system.
2. Remove the laser head cover by removing the 4 screws, then lifting off
the cover.
3. Locate the air purge filter assembly under the tray. It is toward the
umbilical end of the laser head, below the Marx bank.
4. Detach the assembly Clip-Lok fittings from the input panel fitting and
from the manifold T.
5. Lift up on the small black tap on the desiccant filter restraining straps
to release the catch mechanism, and remove the straps.
6. If there is a tie-wrap holding the desiccant filter in place (used only
during initial shipment), use wire cutters to remove it.
7. Note the orientation of the filter assembly, then remove it.
8. Lay the new filter assembly in place, then refasten the black restrain-
ing straps around the desiccant filter.
9. Fasten the input hose to the input panel fitting and the output hose to
the manifold T. Pull on the fittings to verify they latched properly.
10. Install the head cover and tighten the 4 screws.
This completes the procedure for replacing the air filter assembly.
9-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Procedure
Danger! Be wary every time you remove the power supply cover that there is
lethal high voltage inside.
1. Turn off the laser according to the instructions in Chapter 6, then open
the power supply circuit breaker.
Danger! As an extra precaution, open the circuit breaker and disconnect the
power cord.
Figure 9-3: Short together posts A and B to prevent shock when servic-
ing the flash lamps.
9-8
Maintenance
8. Loosen and remove the thumb screws and block from both ends of the
lamp(s).
9. Remove each lamp by moving it toward the middle and pulling it out.
10. Clean the new lamp with methanol.
11. Reverse Steps 6 through 10 to install each lamp.
a. Depending on clearance, insert the proper end of the lamp first.
The anode end is identified by a red mark on its electrode and an
A on the red anode lead. The anode electrode is solid, while the
cathode electrode is segmented and cone-shaped.
b. Make sure all O-rings are seated snugly in the groove of the lamp
housing.
c. Tighten all thumb screws evenly and snugly. Do not overtighten.
d. Bend the ends of the lamp wire down at 90 degrees.
12. Remove the shorting connector from terminal posts A and B.
13. Connect the water hose to the top of the rod assemblies.
14. After installation, test for water leaks as follows:
a. Defeat the cover interlock.
b. Press the ON button long enough to move cooling water into the
lamp housing.
c. If no leaks occur, turn on the water pump and inspect for leaks
again at full pressure.
If there are no leaks after 5 seconds, the seals are tight.
d. Turn off the laser, deactivate the cover interlock defeat, and install
the laser head cover.
15. If a leak occurs:
a. Turn off the laser and observe the danger warning in Step 1.
b. Remove the thumb screws and blocks.
c. Center the lamp in its housing, and check the seating of the O-
rings.
This completes the procedure for replacing the flash lamps.
9-9
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
9-10
Chapter 10 Service and Repair
This chapter is divided into four parts. The first is a general description to
give you a better idea of how the system works at the technical level in the
event you encounter problems while operating your unit. Do not attempt
repairs yourself while the unit is still under warranty; instead, report all
problems to Spectra-Physics for warranty repair.
The second part contains the troubleshooting guide that is for you, the user.
It is meant to assist in isolating some of the problems that might arise while
using the system. A complete repair procedure is beyond the scope of this
manual. For information concerning the repair of your unit by Spectra-
Physics, please call your local service representative or refer to Chapter 11,
Customer Service.
The third part is a replacement parts list of components (and their part
numbers) that are most likely to break or get lost, as well as those you may
simply want to order as spares or substitutes.
The final part gives directions on how to drain and disassemble the system
for shipping. Be sure to read this section before you move your system.
General Operation
This section describes briefly how various parts of the system operate and
what modifications, if any, can be made. References are made throughout
this section to control devices. The first reference is to the control on the
controller provided with the system. The second reference (in parentheses)
is to the control on the GUI interface software also shipped with the system.
Enabling Signals
Enabling signals are used to control laser start-up, analog strobe triggering,
flash lamp firing, select the lamp trigger oscillator, set the Q-switch trigger-
ing mode and to select single-shot or repetitive operation. The controller
supplies enabling signals directly. When the system is operated remotely,
enabling commands may be sent via the RS-232C port or the optional
IEEE-488 interface. Refer to Appendix A for instructions.
Analog Signals
Analog voltages control the flash lamp energy, the variable oscillator, the
Q-switch triggering delay, and the timing of the Q-switch advanced sync
signal. The controller supplies analog signals directly. The computer con-
trol interface (CCI) supplies these analog signals when commanded to do
so by the attached computer or terminal.
10-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Local/Remote Operation
The INT/COMPUTER button on the controller selects the attached computer/
terminal for remote control, or the controller for manual local control. The
RS-232C serial and optional IEEE-488 parallel ports are enabled when
COMPUTER is selected, but only one port can be used at a time.
Q-switch Delay
After the firing signal emerges from the computer test delay, it passes
through a one-shot pulse generator that shapes the wave form to meet the
drive requirements of the voltage-programmable Q-switch delay. The Q-
SWITCH: DELAY control provides an adjustable delay of 50 to 300 ms that
allows the population inversion to develop before Q-switch triggering. this
allows the Q-switch to open at the peak of stored energy.
10-2
Service and Repair
Mode Switch
The MODE switch on the controller (or the QSWITCH knob on the Main
menu) enables one of three sources of Q-switch trigger signals. When set to
Q-SW (NORMAL), a signal from the voltage-programmable delay opens the
Q-switch momentarily at the point of maximum inversion. When set to
LONG PULSE, the flash lamp and Pockels cell are triggered simultaneously,
holding the Q-switch open throughout the lamp pulse. When set to EXTER-
NAL, a signal at the INPUT: Q-SW TRIG connector on the power supply fires
the Pockels cell.
The source of the enabling signal depends on the setting of the INT/COM-
PUTER selector on the controller and, if set to COMPUTER, on the computer
when a computer is connected to the RS-232 interface and the REMOTE
jumper plug is installed (see Local/Remote Operation above). All exter-
nal Q-switch triggering signals enter through the INPUT: Q-SW TRIG con-
nector on the power supply regardless of the INT/COMPUTER setting.
Q-switch Drivers
The output of the SOURCE: FIXED delay switch (LAMPS TRIGGER) passes
through the MODE switch (QSWITCH) when Q-switch mode is enabled and
fires the Marx bank pulse generator. The result is a pulse a few millisec-
onds long that becomes amplified by the Marx bank buffer to produce the
signal that drives the Marx bank. The Q-switch pulse generator stretches
the output of the Marx bank pulse generator to produce a signal that
appears at the OUTPUT: Q-SW SYNC connector on the power supply:
2 V (50 ) pulse width
5 ms with 20 ns rise time
Single-Shot Operation
Firing a single shot requires two signals: one to enable the single-shot flip-
flop and one to fire it. The enabling signal is from either the SINGLE SHOT:
REP switch on the controller or the slide bar control on the Main menu. The
arming signal (get ready to fire signal) is from either the SINGLE SHOT:
FIRE button on the controller or the FIRE position on the Main menu slide
bar control. Once armed, the single-shot circuit fires the Marx bank on the
next available pulse from the lamp trigger signal. Until it is armed again,
the flip-flop prevents the passage of subsequent lamp trigger pulses.
LAMP ON Switch
When the LAMP ON switch (GUI: ON button) is turned off, voltage is
applied to the reset line of the lamp sync pulse generator to prevent lamp
firing. It also turns on the INHIBIT lamp (GUI: LAMPS TRIGGER knob points
to INHIBIT). The inhibit and source fault signals pass through an OR gate
that allows either of them to inhibit firing. The LAMP ON switch remains
active even when under computer control so that the laser can always be
shut off at the controller.
10-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
STOP/ENABLE buttons
The function of the STOP and ENABLE buttons (ON/OFF SWITCH) depends
either on the INT/COMPUTER selector on the controller and, if set to COM-
PUTER, on the computer when a computer is connected to the RS-232
interface and the REMOTE jumper plug is installed (see Local/Remote
Operation above). Under INT control, pressing the ENABLE button (toggle
ON) closes the main relay and activates all power supply circuits. After a 10
second delay, the laser starts. Under COMPUTER control, two signals are
require: an enabling signal that is derived by pressing the controller
ENABLE button or by using the REMOTE jumper plug, and an on signal
from the computer by toggling the ON/OFF SWITCH to on. The lighted
buttons on the controller identify the operating status of the laser, regard-
less of the position of the INT/COMPUTER switch.
The line dropout detector shuts off the laser if it senses a loss of line volt-
age. The initializing circuits prevent transfer of laser control until all power
supplies have energized. They also prevent mishaps due to errors in logic
start-up.
Interlock Logic
The interlock logic examines several sensors to ensure safe, trouble-free
operation: external interlock, laser head and power supply cover switches,
and cooling water temperature and flow. The auxiliary interlock connector
on the back of the power supply is included for simple installation of envi-
ronmental safety devices such as a door switch. If an interlock fault occurs,
the logic trips the main contactor, shutting off power to the switching sup-
ply and simmer transformer. Logic power remains on.
The logic circuit also receives input from the lamp voltage level sensor
which prevents the laser from starting until lamp energy is reduced to
nearly zero. This prevents accidental high power output upon start-up.
If no interlock faults occur, the logic circuit enables the turn-on delay, and,
after 10 seconds, the laser starts.
If one or more faults occur, the laser will not start and the INTERLOCK
FAULT lamp on the power supply and Main menu turn on.
The auxiliary interlock connector operates from a 15 Vdc source in the
power supply and must be wired to a sensing switch using twisted-pair
wire. Because the auxiliary interlock is a possible source of noise, shield
the wire in hostile environments. This shield should be grounded to the
power supply chassis near the auxiliary interlock connector. Use any one of
the chassis mounting screws. Do not attach the shield at any other point.
Pulse-Forming Network
The pulse-forming network (PFN) produces a critically-damped pulse when
the SCR is fired. This pulse drives the flash lamp(s) that pump the Nd:YAG
rods. The switching power supply transforms line voltage (208 Vac, nomi-
nal) into dc voltage for the PFN. The PFN voltage (Vpfn) is programmable:
Vpfn = 187.5 x V
where V = 0 to 8 Vdc.
10-4
Service and Repair
Warning! Before shipping the laser or the power supply, completely drain the
coolant from each. The temperature in an aircraft cargo hold can freeze
the coolant and can cause several components to burst. Such damage is
not covered under your warranty!
Control Setting
Power supply POWER circuit breaker Closed (On)
Power supply POWER key switch On
LAMP ON switch Off (INHIBIT lamp on)
10-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Level Sensor
Return Hose
Deionizing Filter
Reservoir
Particle Filter
Cooling Pump
10-6
Service and Repair
Replacement Parts
Table 10-1: Replacement Parts
Description Part Number
Maintenance
Flash lamps 0450-9080
Deionizing cartridge, cooling system 9800-0600
Particle filter, cooling system 9800-0620
Air filter assembly, Includes: desiccant filter assembly, 9800-0610
particle (micron) filter, and oil filter.
Electrical
Control pc board assembly 0449-7900S
Power pc board assembly 0447-0510S
Fan controller pc board assembly 2203-0071
Simmer pc board 0447-2220
Start circuit assembly 0004-2986S
Marx bank assembly 0004-2087-2S
Contactor 4501-0361
Thyristor, dual, SCR 4802-2482
Switch, circuit breaker 5102-0640
Fuse kit with 0.25 A FB, 0.5 A FB, 0.5 A SB, 1.5 A SB, 4 A 9850-0650
SB, switching regulator, 1 A SB, 1 A FB, 1/8 A SB, 1/16 A
FB, and 30 A SB
Optical
Thin film polarizer 0005-0021
Output mirror contact factory
Q-switch, 10 mm 0100-4460
Q-switch, 13 mm 0447-3300
Gold pump cavity consult factory
High reflector contact factory
Nd:YAG rods consult factory
Dichroic mirror, 532 nm 0441-6070
Dichroic mirror, 355 nm 0449-5370
Dichroic mirror, 266 nm 0449-5360
Half-wave plate, 1064 nm 0002-0053
Half-wave plate, 532 nm 0002-0050
Quarter-wave plate, 1064 nm, Laser 0005-0140
HG WIndow 0002-0061
HG Window Quartz 0002-0061-1
Mechanical
Model BD-5 Beam Dump BD-5
Model BD-6 Beam Dump BD-6
10-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
10-8
Chapter 11 Customer Service
Customer Service
At Spectra-Physics, we take great pride in the reliability of our products.
Considerable emphasis has been placed on controlled manufacturing meth-
ods and quality control throughout the manufacturing process. Neverthe-
less, even the finest precision instruments will need occasional service. We
feel our instruments have excellent service records compared to competi-
tive products, and we hope to demonstrate, in the long run, that we provide
excellent service to our customers in two ways: first by providing the best
equipment for the money, and second, by offering service facilities that get
your instrument repaired and back to you as soon as possible.
Spectra-Physics maintains major service centers in the United States,
Europe, and Japan. Additionally, there are field service offices in major
United States cities. When calling for service inside the United States, dial
our toll free number: 1 (800) 456-2552. To phone for service in other coun-
tries, refer to the Service Centers listing located at the end of this section.
Order replacement parts directly from Spectra-Physics. For ordering or
shipping instructions, or for assistance of any kind, contact your nearest
sales office or service center. You will need your instrument model and
serial numbers available when you call. Service data or shipping instruc-
tions will be promptly supplied.
To order optional items or other system components, or for general sales
assistance, dial 1 (800) SPL-LASER in the United States, or 1 (650) 961-
2550 from anywhere else.
Warranty
This warranty supplements the warranty contained in the specific sales
order. In the event of a conflict between documents, the terms and condi-
tions of the sales order shall prevail.
Unless otherwise specified, all parts and assemblies manufactured by Spectra-
Physics, except optics, are unconditionally warranted to be free of defects
in workmanship and materials for a period of two years following delivery
of the equipment to the F.O.B. point. All optics are warranted for 90 days.
Liability under this warranty is limited to repairing, replacing, or giving
credit for the purchase price of any equipment that proves defective during
the warranty period, provided prior authorization for such return has been
given by an authorized representative of Spectra-Physics. Spectra-Physics
will provide at its expense all parts and labor and one-way return shipping
11-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Warning! Always drain the cooling water from the laser head and power supply
before shipping. Water expands as it freezes and will damage the laser.
Even during warm spells or summer months, freezing may occur at high
altitudes or in the cargo hold of aircraft. Such damage is excluded from
warranty coverage.
11-2
Customer Service
Service Centers
Benelux
Telephone: (31) 40 265 99 59
France
Telephone: (33) 1-69 18 63 10
Germany and Export Countries*
Spectra-Physics GmbH
Guerickeweg 7
D-64291 Darmstadt
Telephone: (49) 06151 708-0
Fax: (49) 06151 79102
Japan (East)
Spectra-Physics KK
East Regional Office
Daiwa-Nakameguro Building
4-6-1 Nakameguro
Meguro-ku, Tokyo 153
Telephone: (81) 3-3794-5511
Fax: (81) 3-3794-5510
Japan (West)
Spectra-Physics KK
West Regional Office
Nishi-honmachi Solar Building
3-1-43 Nishi-honmachi
Nishi-ku, Osaka 550-0005
Telephone: (81) 6-4390-6770
Fax: (81) 6-4390-2760
e-mail: niwamuro@splasers.co.jp
United Kingdom
Telephone: (44) 1442-258100
United States and Export Countries**
Spectra-Physics
1330 Terra Bella Avenue
Mountain View, CA 94043
Telephone: (800) 456-2552 (Service) or
(800) SPL-LASER (Sales) or
(800) 775-5273 (Sales) or
(650) 961-2550 (Operator)
Fax: (650) 964-3584
e-mail: service@splasers.com
sales@splasers.com
Internet: www.spectra-physics.com
*
And
all European and Middle Eastern countries not included on this list.
**
And all non-European or Middle Eastern countries not included on this list.
11-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
11-4
Appendix A Status/Error Codes
Table A-1 lists the status and error codes for the Lab-Series laser system.
The codes are generated by the embedded controller in the power supply.
When Spectra-Physics GUI control software is used, these codes are dis-
played in the history buffer window located at the bottom of the Info panel.
When user-written software is used, these codes can be accessed via que-
ries. Appendix B, Programming Reference Guide, at the end of this man-
ual contains information on how to do this.
These codes are three-digit numbers. The fist digit relates to internal laser
conditions that are useful for Spectra-Physics diagnostics and debugging,
but may be ignored by the system operator. The second and third digits
indicate the actual error being reported. Thus, error codes 101, 201 and 301
should all be interpreted as reporting the same error, 01, which is interlock
error.
Table A-1: Status/Error Codes
Status Code Description
01 Interlock error
02 Laser ID mismatch
03 Low water
04 Reserved
05 AC dropout detected
06 Unexpected loss of internal power.
07 Oscillator SIMMER failure
08 N/A
09 Reserved
10 Reserved
11 Watchdog timeout
1298 Reserved
99 Unknown error
A-1
Appendix B Lab-Series Programming Guide
B-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Introduction
The command language for the Quanta-Ray laser system is based on the SCPI (Standard Commands
for Programmable Instruments) protocol. The specification for that language can be found at
www.SCPIConsortium.org. The Quanta-Ray laser is not 100% compliant with the standard, but does
use it as a guide.
Commands to the laser may be terminated with <CR>, <LF>, or both. Responses from the laser are
normally terminated with <LF> can be modified (refer to ECHO Command).
Every command has both a short and long form. This document uses a special notation to
differentiate the short form command from the long form of the same command. The long form of
the command is shown, with the short form portion shown in uppercase characters, and the rest of
the keyword is shown in lowercase characters. However, commands sent to the laser are not case
sensitive. Consider the listing for the command to set lamp trigger mode. The laser would consider
any of these commands to be equivalent:
However,
LAMPs FIXE?
would be invalid ---- FIXE doesnt match either the short form fix or the long form (fixed)
subcommand.
Most commands take parameters, separated by a space. The READ and STATus commands take
subcommands separated by a colon. Queries return a value and units. The units can be used to
verify that the lasers answers are synchronized with your control computers questions. Units may
consist of a traditional unit. For example, QSWitch DELay? returns a string such as 191.075
171.1 231.1 s . 191.075 s is the value that Q-switch delay is set for and 171.1 231.1 s are
the minimum and maximum value of Q-switch delay respectively.
B-2
Lab-Series Programming Guide
General-purpose commands include all commands except those specifically relating to detecting
errors. Examples of commonly used commands are turning the laser on and off, changing lamp
trigger source, or changing Q-switch trigger mode.
HELP
HELP
SETUP commands:
ECHo HELP
OPERATIONAL commands:
*CLS *ESR *IDN *RST *STB
APFN BAUD BLOK DLOK LAMPs
OFF ON OPFN QSWitch READ
SHOTs STATus WATChdog
*IDN?
This command returns the product identification string as defined by the SCPI standard. The
response to the IDN command contains four fields (manufacturer, model, serial number, and
firmware version) separated by commas. A typical response from the laser would be
Spectra Physics,QUANTA-RAY-LAB170-10,2404l,0452-0023A/0456-6600A
(company name) (product id) (Serial No) (GCR firmware) / (FPGA firmware)
Examples:
*IDN? <CR>
Spectra Physics,QUANTA-RAY-LAB170-10, 2404l,0452-0023A/0456-6600A <LF>
ON
This command is used to turn on the laser. The normal sequence is:
Example:
ON <CR> turn on the system
B-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
OFF
This command is used to turn off the laser. The normal sequence is:
The *STB? command can be used to monitor the turn off sequence.
Example:
OFF <CR> turn off the system
LAMPs <m>
LAMPs?
Mode<m>=EXTernal, FIXed, VARiable, INHibit
This command is used to select or identify the lamp trigger source. It is also used to set the variable
trigger rate.
Example:
LAMP FIX <CR> Lamp trigger is set to Fixed.
LAMP EXT <CR> Lamp trigger is set to External Source.
LAMP VAR <CR> Lamp trigger is set to Variable.
LAMP VAR 8.2 <CR> Variable Rate is set to 8.2 pulses per second.
LAMP VAR? <CR> To what value is the lamp Variable Rate trigger set?
10.0 VAR <CR> Lamp trigger is set to Variable and repetition rate is 8.2 pulses per sec.
LAMP INH <CR> Lamp trigger(s) are Inhibited.
LAMP? <CR> Identify lamp trigger.
INHibit <LF> Indicates the lamp is Inhibited.
QSWitch <m>
QSWitch <t>
QSWitch ADVance [value]
QSWitch DELay [value]
QSWitch ADVance?
QSWitch DELay?
QSWitch?
Modes<m> = EXTernal, LONGpulse, NORMal
Types<t> = FIRe, REPetitive, SINGleshot
Example:
QSW LONG <CR> Sets the Q-switch to its Long Pulse mode.
QSW SING <CR> Sets the Q-switch to Single-Shot type.
QSW FIRe <CR> Fires the Q-switch once.
QSW? <CR> What is the Q-switch setting?
B-4
Lab-Series Programming Guide
LONGpulse SINGleshot <LF> Indicates the Q-switch is set to Long Pulse mode and Single-
Shot type.
Reminder: QSWitch DELay and ADVance are only meaningful in NORMal mode.
QSW ADV 250 <CR> Sets the Q-switch Advance Sync to 250.00.
QSW ADV? <CR> To what value is Q-switch Advance Sync set?
250.00 700.0 500.0 ns Indicates the Q-switch Advance Sync is 250.0, the min value is
700.0 ns and the max value is 500.0 ns.
QSW DEL? <CR> To what value is Q-switch Delay set?
210.00 120.0 250.0 s Indicates the Q-switch Delay is set to 210.0 s, the min value
is 120.0 s and the max value is 250.0 s.
APFN<n>
APFN?
Range: n = 0 100%
The APFN command sets the Amplifier PFN voltage as a percentage of factory full scale.
Example:
APFN 100 <CR> Sets the APFN voltage to 100.0%.
APFN? <CR> To what value is APFN set?
100.0 % <LF> Indicates APFN is set to 100.0%.
OPFN<n>
OPFN?
Range: n = 0-100%
The OPFN command sets the Oscillator PFN voltage as a percentage of factory full scale.
Example:
OPFN 100 <CR> Sets the OPFN voltage to 100.0%.
OPFN? <CR> To what value is OPFN set?
100.0 % <LF> Indicates OPFN is set to 100.0%.
*STB?
The status byte is the central component of the SCPI status system. Properly interpreting this byte
allows the operator to determine the overall operating condition of the laser system. See Section 2:
Status/Error Reporting for information on interpreting the status byte and other status registers.
*RST?
B-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
SHOTs?
This command returns the number of shots on the lamps, or resets the counter when the lamp is
replaced. Note: this command returns the actual number of shots while the mechanical counter on
the front panel reports shots rounded to the nearest 100.
Example:
SHOT? <CR> How many shots are on the lamps?
1134 <LF> 1134 (the mechanical counter on the power supply would report 1100)
SHOT 0 <CR> resets the lamp shots counter to zero
ECHo <n>
ECHo?
This command modifies the way the control computer interacts with the laser. The <n> parameter is
an integer that specifies a bit pattern. The bits are defined as follows:
Bit Description
0 show prompts
1 the laser echoes characters as they are received
2 shows error messages
3 output at least a line feed for every command (even ones that do not normally
generate a response)
4 terminate responses with <CR><LF>, rather than just <LF>
5 use XON/XOFF handshaking for data sent to the laser
(No handshaking is used for data sent from the laser)
The previous Echo mode is replaced at power up and is unaffected by the *RST command. When
Echo is set to zero, the laser will not issue a response unless a command requires it, and the response
will be terminated with a <LF> character.
Examples:
ECH? <CR> What is the current Echo mode?
0 <LF> The system responds: ECHO 0.
ECH 1 <CR> Set to Echo 1 mode.
!Ready <LF> Laser prompts that it is ready.
ECH 17 <CR> Request both prompt and <CR><LF> termination.
!Ready <CR><LF> Laser prompts that it is ready.
ECH 21 <CR> Request prompt and error messages.
!Ready <CR><LF> Laser prompts that it is ready.
LMP FIX Send an illegal command (should be LAMPs FIXed).
What? <LF> Laser prompts that it does not understand the command.
!Ready <LF> Laser prompts that it is ready.
ECH 8 <CR> Request <LF> for all commands, no prompts or warnings.
<LF> The <LF> verifies that a command was received
B-6
Lab-Series Programming Guide
WATChdog <n>
Range: 0 to 110 seconds.
This is the RS-232 laser/control computer communication watchdog timer. If the laser does not
receive communications from the control computer within the specified time, it turns itself off. The
default value is zero (disabled).
This command allows users to set their own comfort level for a safety check on their control
computer. Values from 3 to 10 seconds are typical.
Example:
WATC 5.1 <CR>
BAUD<n>
Values for n = 2400, 4800, 9600, 19200, 38400
This command sets the communications speed between the laser embedded computer and the users
control computer. At power-up, the laser always communicates at 9600 baud. The baud rate is not
affected by the *RST command.
Example:
BAUD 38400
The READ commands are used to learn what the laser is actually doing, as opposed to what it has
been asked to do. A few reasons the READ commands can return something different than what was
commanded by a control computer are:
1 The control computer is not actually in control. A remote panel or an external BeamLok
controller is in control.
2 The system may be in a turn-on or turn-off sequence. For example: when the system is turned
off, it is normal for APFN? to indicate a commanded value of 100%, and READ:APFN to report
an actual value of 0%.
3 Under certain conditions the system will automatically decrease the PFN voltages to 90% of the
nominal settings in order to prevent optical damage. A typical example is when the Q-Switch is
set to Single-Shot type.
READ:OPFN?
READ:APFN?
These queries return the oscillator or amplifier PFN command setting in percent (i.e., what the PFN
power supply is being asked to do).
Example:
READ: APFN? <CR>
0.0 % <LF>
B-7
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
READ:OMON?
READ:AMON?
These queries return the oscillator or amplifier PFN monitor in percent (i.e., what the PFN power
supply is actually doing).
Example:
READ: AMON? <CR>
0.0% <LF>
READ: QSWADV?
Example:
READ:QSWADV? <CR>
200.0 ns <LF>
READ: QSWDEL?
Example:
READ:QSWDEL? <CR>
210.0 s
READ: SHOTs?
Example:
READ:SHOT? <CR>
429 <LF>
READ: VARiable?
This query returns the lamp trigger rate, unless the lamp trigger source is external.
Example:
READ:VAR? <CR>
10.1 VAR <LF>
B-8
Lab-Series Programming Guide
One of the most powerful (and therefore complex) parts of the SCPI protocol is its error reporting
facility. Status is reported in a tree-like structure where the root of the tree is the status byte. Users
should regularly check this byte for information about basic conditions such as laser emission, water
pump on, and interlock status. It also discloses any questionable conditions that might exist.
Questionable conditions are those that might raise doubts about laser system performance (such as
a power supply that cannot properly charge the high voltage capacitor). If questionable conditions
are reported, then further information can be requested.
*STB?
This query returns the status byte, which is the top level of the SCPI information data structure. The
value returned is an integer representing a 32-bit value, which, when properly interpreted, discloses
the condition of the laser.
A programming example of how to use this status byte to access the SCPI data structure is included
at the end of this appendix.
Bit Description
Number
0 Laser emission can occur
1 (reserved)
2 Data is in the error log, use READ:HIST?
3 Check STAT:QUES bits
4 (reserved)
5 Check *ESR bits
6 (reserved)
7 Check STS:OPER bits
8 Main contactor is energized
9 Oscillator simmer is on
10 Amplifier simmer is on
11 Oscillator PFN is at target
12 The laser has recently fired
13 15 Vdc power supply failure
14 Laser cover interlock open
15 One or more of the following interlocks is open: CDRH plug, power supply cover,
laser head cover, laser head temperature, water pressure, water flow
16 Remote panel disconnected
17 Internal 208 Vac failure
18 CDRH enable failure
19 Laser ID fault
20 Low water fault
B-9
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
21 Interlock fault
22 A remote panel is connected
23 the remote panel indicates that the computer is in control.
24 The main contactor should be on
25-31 (reserved)
To properly interpret the power supply interlock state, first consider bits 13 through 21. The laser has
three interlock priorities: bits 19, 20, and 21, with bit 19 being the most important. Bits 13 through
18 do not contain useful information unless bit 21 is true (high).
If bit 23 is low, the remote panel is in control, and commands that attempt to set a value (such as
LAMPs or QSWitch) have no effect on the laser. Any command that asks for information (such as
READ:SHOTs?) operate as expected. The ON and OFF commands will operate as expected, even if
the remote panel is in control.
Example:
*STB? <CR> Send status byte.
139 <LF> The requested status byte states that the laser has emission, the shutter is open
and something is questionable about the laser. Use the STATus:QUES com-
mand to determine which conditions have set the questionable bit.
STATus:QUEStionable?
This query returns the questionable condition register. It is an extension of the basic status byte, and
it can give more information about subsystems within the laser. Bit 3 of the status byte (*STB?) is a
logical-OR of bits 9, 10, and 11. If Bit 3 of the status byte is false (low), there is no need to check
the STATus:QUEStionable register for additional information.
Bits 0 through 8 and 12 through 15 are undefined and are reserved for future use.
Bit 9 is set if the oscillator high-voltage (HV) power subsystem does something unexpected. If bit 9
is true (high), then bits 16 through 23 should be examined to identify the fault. If Bit 9 is false, bits
16 through 23 should be ignored.
Bit 10 is set high if the amplifier high-voltage (HV) power subsystem does something unexpected.
If bit 10 is true, bits 24 through 31 should be examined to identify the fault. If bit 9 is false, bits 24
through 31 should be ignored.
Bit 11 is set when an EXTernal LAMPs trigger has occurred at a rate that is outside the specified
MIN and MAX limits.
Bit Description
number
08 (reserved)
09 Oscillator HV failure
10 Amplifier HV failure
11 External Trigger Rate out of range
B-10
Lab-Series Programming Guide
Example:
STAT:QUES? <CR> What is the status of the system?
512 <LF> The system reports that the oscillator high-voltage is not ok.
*CLS
This command clears the status byte and status questionable register. Use it to make sure there is no
left over information in these registers from a previous error. The history buffer (READ:HISTory)
is not affected by *CLS, even though bit 2 of the status byte remains zero until a new error occurs.
READ:HISTory?
This query returns up to 16 status/error codes from the system history buffer. If the laser has shut
itself off or the system is behaving erratically, investigate the answer to this query. The first element
in this history buffer is the most recent. A complete listing of the laser history buffer error codes is
included in Appendix A.
This query returns at lest two lines of information, each of which consists of two numbers. The first
number in the first line is the number of items in the buffer. The second number in first line is the
number of seconds since power up. The final line is always 0 0. Intermediate lines contain the
error code followed by the system time when the error occurred.
Example:
READ:HIST? <CR> Request for history buffer
1 827 <LF> 1 error has occurred, current time is 827 sec
301 810 <LF> Error code 301 occurred at 810 sec
0 0 <LF> End of history buffer
Section 2.2: C Language Example Using the Status Byte to check for Interlocks
B-11
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
#defineSTB_LASER_ID BIT_19
#defineSTB_LO_WATR BIT_20
#defineSTB_ILK_NOK BIT_21
#defineSTB_INTERLOCK1 BIT_13
#defineSTB_INTERLOCK2 BIT_14
#defineSTB_INTERLOCK3 BIT_15
#defineSTB_INTERLOCK4 BIT_16
#defineSTB_INTERLOCK5 BIT_17
#defineSTB_INTERLOCK6 BIT_18
B-12
Lab-Series Programming Guide
B-13
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
B-14
Notes
Notes-1
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Notes-2
Notes
Notes-3
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Notes-4
Notes
Notes-5
Quanta-Ray Lab-Series Pulsed Nd:YAG Laser System
Notes-6
Report Form for Problems and Solutions
We have provided this form to encourage you to tell us about any difficul-
ties you have experienced in using your Spectra-Physics instrument or its
manualproblems that did not require a formal call or letter to our service
department, but that you feel should be remedied. We are always interested
in improving our products and manuals, and we appreciate all suggestions.
Thank you.
From:
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