JP2003340587A - Laser beam processing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method which enables lighting from the rear side of a printed circuit board without wiring or the like to an X-Y table and can measure a reference mark with high accuracy. <P>SOLUTION: The laser beam processing machine has a camera 12 to detect the reference mark 17 of a workpiece and a lighting device. The lighting from the rear side of the workpiece can be executed by installing illumination light sources 22, 23 for the camera on the upper side or the side of the workpiece and by reflecting the light emitted from the illumination light sources 22, 23 by providing a reflection part 24 inside the X-Y table. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser beam machine having an illuminating device for easily detecting a reference mark on a printed circuit board, especially in punching a printed circuit board.

[0002]

2. Description of the Related Art Printed circuit boards, which are widely used as substrates for personal computers and mobile phones, are remarkably miniaturized and highly functionalized year by year, and wiring patterns are becoming finer.

Along with this, a laser beam machine for punching a printed circuit board is subject to distortion of the printed circuit board to be machined placed on the XY table and angular deviation from the coordinate axes of the XY table. It needs to be accurately measured and corrected.
For this reason, a mark (hereinafter referred to as a reference mark) that serves as a reference is provided on the printed circuit board using the inner metal layer, and the reflected light from the reference mark is read and measured by a CCD camera or the like.

However, since the reference mark becomes smaller due to the miniaturization of the wiring pattern, the amount of light reflected from the reference mark decreases, and the reflection from the surface of the resin above the reference mark becomes relatively stronger. Moreover, it is becoming difficult to measure the reference mark.

As a solution to this, for example, Japanese Examined Patent Publication No. 63-2
As disclosed in Japanese Patent No. 5885, a method of guiding an optical fiber to an XY table to illuminate a printed circuit board from the back side, and as disclosed in Japanese Patent No. 3023320, a light source itself is attached to an XY table. A method of arranging and illuminating the printed circuit board from the back side to improve the contrast of the reference mark has been proposed.

[0006]

In the case of a method of embedding an optical fiber or a light source in an XY table, since there are fibers and wiring, it is necessary to lengthen the wiring.
In addition, there is a problem in terms of the storage method and securing a space for storage.

Therefore, the present invention is to provide a method capable of illuminating from the back side of a printed circuit board and performing highly accurate measurement of a reference mark without wiring the XY table.

[0008]

In the laser beam machine of the present invention, an illumination light source for a camera is installed above or beside a workpiece, and a reflection section is provided inside the XY table so that the illumination light source can be operated from the illumination light source. It is characterized by having an illuminating device capable of illuminating the workpiece from the back side by reflecting the emitted light.

Since only the light reflecting portion is provided on the XY table, there is no need for wiring, and it is possible to solve the problem of the storage method and the space for securing the storage.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 9 shows the configuration of a laser processing machine according to the present invention. The laser beam 2 output from the laser oscillator 1 is applied to the printed circuit board 8 fixed on the Y table 9 through the total reflection mirrors 3 and 4, the galvano mirrors 6a and 6b rotated by the scanner motors 5a and 5b, and the fθ lens 7. XY table drive by an X table 10 having an optical system mechanism to be processed and a drive system including a linear bearing and a servo motor on a base 11, and a Y table 9 having a drive system including a linear bearing and a servo motor on the X table. System mechanism, Y
It is composed of a camera 12 mounted in a fixed positional relationship with an optical system mechanism for detecting a positioning mark of the printed circuit board 8 placed on the table 9, and these optical system mechanism, drive system mechanism, and camera are used as an NC device 16 Controlled by. The laser oscillator 1 is controlled by the power supply / controller 15.

FIG. 1 is a perspective view of the vicinity of a processing head of a laser processing machine according to the present invention. 2 is a laser beam, 5 is a scanner motor, 6 is a galvanometer mirror, 7 is an fθ lens,
8 is a printed circuit board, 9 is a Y table, 10 is an X table, 12 is a camera for detecting a reference mark, 17 is a reference mark for attitude and positioning of the printed circuit board 8, 22 and 23 are light sources, and 24 is a light source. This is a reflection part for reflecting the light from the back side and illuminating the vicinity of the reference mark 17 on the printed board from the back side.

The light emitted from the light source 22 is reflected by the reflecting portion 24 to illuminate the reference mark 17 provided on the printed circuit board 8 from the back side, and the transmitted image is detected by the camera 12. When the Y table moves and the reference mark on the opposite side of the printed circuit board 8 is detected, light is emitted from the light source 23 and illuminated by using the reflecting section on the opposite side. As described above, according to the present invention, it is possible to illuminate the rear surface with two light sources. Further, since the light sources 22 and 23 need only be attached to the laser processing head that does not move much during processing, it is not necessary to consider routing of wiring due to movement of the table.

FIG. 2 is a plan view near the reference mark on the printed circuit board 8, and FIG. 3 is a sectional view taken along the line AA. 17
Is a reference mark, 18 and 21 are insulating resin layers, 19 is an inner layer pattern, and 20 is an insulating substrate. The reference mark 17 is
Usually, it is the same copper foil layer as the inner layer pattern 19 forming the electric wiring. In many cases, the insulating resin layers 18 and 21 are made of epoxy resin, and the insulating substrate 20 is made of glass fiber reinforced epoxy resin. Here, regardless of which material is used, the insulating substrate 20 and the insulating resin layers 18 and 21 have high light transmittance,
Since the reference mark 17 is made of metal, it reflects light. Therefore, when illuminating from the back surface of the printed circuit board 8, an image with good contrast of the reference mark 17 can be obtained without being bothered by the reflected light from the surface of the insulating resin layer 18.

[0014]

EXAMPLES Specific examples of the reflecting portion 24 according to the present invention will be described below. (Embodiment 1) FIG. 4 shows a case where a mirror-finished metal plate is bent to form reflecting mirrors 25 on both sides which face each other at an angle, and the reflecting mirrors 25 are installed in a cavity provided in the Y table 9 to reflect light. An example of configuring the unit 24 is shown. The light emitted from the light source 22 (thick arrows and thin lines on both sides thereof) is reflected by the reflection mirror 2.
5, the reference mark 17 is illuminated from the back side, and the reference mark 17 is detected by capturing a transmission image with the camera 12.

(Embodiment 2) FIG. 5 shows two reflecting mirrors 2.
An example in which 6 and 27 are installed so as to face a cavity provided in the Y table 9 at an angle to form the reflection section 24 will be described. The light emitted from the light source 22 (thick arrows and thin lines on both sides thereof) is reflected by the reflection mirrors 26 and 27, the reference mark 17 is illuminated from the back side, and the reference mark 17 is detected by capturing a transmission image with the camera 12. To be done.

(Embodiment 3) In FIG. 6, the light source 22 is arranged on the side surface of the Y table 9, and the reflection portion 24 is arranged so that the light irradiates the reflection mirror 27 installed in the cavity provided in the Y table 9. A configuration example is shown. Light emitted from the light source 22 (thick arrows and thin lines on both sides thereof) is reflected by the reflection mirror 27, illuminates the reference mark 17 from the back side, and the reference mark 17 is detected by capturing a transmission image with the camera 12. .

(Embodiment 4) FIG. 7 shows an example in which the light diffusing body 28 is installed in the hollow portion provided in the Y table 9 instead of the reflecting mirror to form the reflecting portion 24. Light emitted from the light source 22 (thick arrows and thin lines on both sides thereof) is diffusely reflected by the light diffuser 28, reflected by the cavity surface of the Y table 9, illuminates the reference mark 17 from the back side, and the transmitted image is taken by the camera 12. The reference mark 17 is detected by photographing. As the light diffuser 28, various commercially available products such as a holographic optical element and a fly's eye lens can be used.

(Embodiment 5) FIG. 8 shows that the reflecting portion 2 is formed by inclining the side surface shape of the cavity provided in the Y table 9.
4 shows an example in which No. 4 is configured. When the inner surface of the cavity is mirror-polished, the reflection efficiency is further improved. Light emitted from the light source 22 (thick arrows and thin lines on both sides thereof) is reflected by the inclinations of both side surfaces of the hollow portion, illuminates the reference mark 17 from the back side, and the camera 12 captures a transmission image so that the reference mark 1
7 is detected. In the case of this embodiment, unlike the other embodiments, there is no need to install a structure in the cavity, and there is an advantage that only the cavity having the inclined side surface is processed on the Y table 9.

In addition, in FIG. 8, both side surfaces are inclined, but
When an experiment was conducted using only the side surface on the light source side as an inclined surface with a slight angle, the accuracy of position measurement was slightly reduced, but better results than before were obtained.

[0020]

According to the present invention, since the reflection portion is used to illuminate from the back surface of the printed circuit board, it is possible to measure the reference mark with high accuracy without wiring the XY table.

[Brief description of drawings]

FIG. 1 is a perspective view around a processing head of a laser processing machine according to the present invention.

FIG. 2 is a plan view around a reference mark on a printed circuit board.

FIG. 3 is a sectional view taken along line AA.

FIG. 4 is a sectional configuration diagram of a reflecting portion according to the present invention (Example 1).

FIG. 5 is a sectional configuration diagram of a reflecting portion according to the present invention (Example 2).

FIG. 6 is a sectional configuration diagram of a reflecting portion according to the present invention (Example 3).

FIG. 7 is a sectional configuration diagram of a reflecting portion according to the present invention (Example 4).

FIG. 8 is a sectional configuration diagram of a reflecting portion according to the present invention (Example 5).

FIG. 9 is a configuration diagram of a laser processing machine according to the present invention.

[Explanation of symbols]

1 ... Laser oscillator 2 ... Laser beam 3, 4 ... Total reflection mirror 5a, 5b ... Scanner motor 6a, 6b ... Galvo mirror 7 ... fθ lens 8: Printed circuit board 9 ... Y table 10 ... X table 11 ... Base 12 ... Camera 15 ... Power supply / Controller 16 ... NC device 17 ... Standard mark 18 ... Insulating resin layer 19: Inner layer pattern 20 ... Insulating substrate 21 ... Insulating resin layer 22, 23 ... Light source 24 ... Reflector 25 ... Bent reflection mirror 26, 27 ... Reflective mirror 28 ... Light diffuser

Claims (6)

[Claims] 1. An optical system mechanism comprising a laser oscillator, a reflection mirror, a galvano mirror, and a focus lens, a drive system mechanism for XY positioning of a workpiece, and a reference mark for detecting the workpiece. In a laser processing machine composed of a camera and an illumination device, an illumination light source for a camera is installed on an upper side or a side of a workpiece, and a reflection section is provided inside an XY table to reflect light emitted from the illumination light source. Therefore, the laser processing machine is provided with an illuminating device that can illuminate the workpiece from the back side. 2. A reflection part is constituted by bending a mirror-finished metal plate and installing reflection mirrors formed on both sides so as to face each other at an angle in a cavity provided in an X or Y table. The laser processing machine according to claim 1. 3. The laser processing according to claim 1, wherein two reflecting mirrors are installed so as to face the cavity provided in the X or Y table at an angle so as to constitute a reflecting portion. Machine. 4. A light source is arranged on a side surface of an X or Y table,
The laser processing machine according to claim 1, wherein the reflecting portion is configured so that the light irradiates a reflecting mirror installed in a cavity provided in the table. 5. The laser beam machine according to claim 1, wherein the light diffuser 27 is installed in a cavity provided in the X or Y table to form a reflection portion. 6. The laser processing machine according to claim 1, wherein the reflecting portion is formed by inclining the side surface shape of the hollow portion provided on the X or Y table.