CN104236726A - Spectrum phase interference device and ultrashort light pulse electric field direct reconstruction system - Google Patents

Abstract

The invention is applicable to the field of optoelectronic technology, and provides a spectral phase interference device and an ultrashort optical pulse electric field direct reconstruction system. The spectral phase interference device introduces a two-step phase shift technology based on the existing SPIDER device, which can facilitate The spectral interference pattern of two complementary interference fringes can be obtained accurately. In data processing, it is no longer necessary to use a time window to filter out the DC flow, thereby eliminating the influence of the time overlap of the DC flow and the AC flow on the measurement results, and greatly improving the measurement results. precision. Therefore, the spectral phase interference device is widely used in various ultrashort optical pulse electric field direct reconstruction systems, and is especially suitable for measuring ultrashort pulse time/spectral characteristics with complex spectral shapes or narrow spectra.

Description

A spectral phase interference device and an ultrashort optical pulse electric field direct reconstruction system

technical field

The invention belongs to the field of optoelectronic technology, in particular to a spectral phase interference device and an ultrashort optical pulse electric field direct reconstruction system.

Background technique

Ultrashort laser pulses have been widely used in various fields such as physics, chemistry, materials, biomedicine, national defense, and industrial processing. Since the end of the 1980s, research on ultrashort optical pulses has never stopped. These include the generation and amplification technology of shorter and stronger ultrashort pulses, the diagnostic technology of ultrashort pulses, and the continuous development of various new application fields. Among various ultrashort pulse measurement techniques, autocorrelation measurement is the most commonly used technique, which is characterized by simplicity and ease of use. But it can only measure the pulse width approximately but not the shape and phase of the pulse. Frequency-resolved optical shutter technology can measure the shape, width, and phase of optical pulses, and its structure is relatively simple, but its complex data processing limits its work efficiency and real-time diagnostic capabilities. The SPIDER technique using conventional spectral shearing interferometry can also measure the width, shape and phase of optical pulses. Its advantages are: the measurement is carried out in the spectral domain and does not require a fast-response receiver; the device does not contain any moving components, which is stable and reliable; the generation algorithm is simple, which is conducive to real-time detection with high repetition rate. The disadvantage is that for ultrashort pulses with complex spectral shapes or narrow spectra, the measurement accuracy is relatively poor.

Contents of the invention

The purpose of the embodiments of the present invention is to provide a spectral phase interference device for direct reconstruction of an ultrashort optical pulse electric field, aiming at improving the measurement accuracy of the existing spectral phase interference device.

The embodiment of the present invention is achieved in this way, a spectral phase interference device, comprising:

It is used to obtain the chirped pulse and the first sub-pulse to be measured and the second sub-pulse to be measured with the same characteristics, and to make the chirped pulse act on the first sub-pulse to be measured and the second sub-pulse to be measured respectively to generate A sum frequency crystal of the first sum frequency pulse and the second sum frequency pulse;

The first sum-frequency pulse is used to divide the first sum-frequency sub-pulse into a first sum-frequency sub-pulse and a second sum-frequency sub-pulse, and the second sum-frequency pulse is divided into a third sum-frequency sub-pulse and a fourth sum-frequency sub-pulse. Three beam splitters;

a first phase shifting mechanism for superimposing said first sum frequency sub-pulse with a third sum frequency sub-pulse to produce a first spectral interference pattern;

a second phase shifting mechanism for superimposing said second sum frequency sub-pulse with a fourth sum frequency sub-pulse to produce a second spectral interference pattern;

a spectrometer for acquiring said first and second spectral interference patterns; and

a processor for processing the first spectral interference pattern and the second spectral interference pattern to obtain characteristics of the first sub-pulse to be measured or the second sub-pulse to be measured;

Wherein, the first phase shifting mechanism and the second phase shifting mechanism respectively have the functions of making the first sum frequency sub-pulse and the second sum frequency subpulse or making the third sum frequency subpulse and the fourth sum frequency subpulse generate π or - π phase shifted second and third wave plates.

Another object of the embodiments of the present invention is to provide a system for direct electric field reconstruction of ultrashort optical pulses using the above-mentioned spectral phase interference device.

The embodiment of the present invention introduces two-step phase shift technology on the basis of the existing SPIDER device, so that two spectral interference patterns with complementary interference fringes can be obtained conveniently, and it is no longer necessary to use a time window to filter out the DC flow in data processing, thereby eliminating The impact of the time overlap of DC and AC on the measurement results is eliminated, thereby improving the measurement accuracy and measurement range. Therefore, the spectral phase interference device is widely used in various ultrashort optical pulse electric field direct reconstruction systems, and is especially suitable for measuring ultrashort pulse time/spectral characteristics with complex spectral shapes or narrow spectra.

Description of drawings

Fig. 1 is an optical path structure diagram of a spectral phase interference device provided in Embodiment 1 of the present invention;

Figure 2 is a schematic diagram of the beam polarization plane being modulated and deflected after the linearly polarized light passes through the half-wave plate;

Fig. 3 is a schematic structural view of a polarization-independent non-dispersive beam splitter;

Fig. 4 is an optical path structure diagram of the spectral phase interference device provided by Embodiment 2 of the present invention; and

Fig. 5 is a diagram of the optical path structure of the spectral phase interference device provided by the third embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The embodiment of the present invention introduces two-step phase shift technology on the basis of the existing SPIDER device, so that two spectral interference patterns with complementary interference fringes can be obtained conveniently, and it is no longer necessary to use a time window to filter out the DC flow in data processing, thereby eliminating The impact of the time overlap of DC and AC on the measurement results is eliminated, and the measurement accuracy is improved. Therefore, the spectral phase interference device is widely used in various ultrashort optical pulse electric field direct reconstruction systems, and is especially suitable for measuring ultrashort pulse time/spectral characteristics with complex spectral shapes or narrow spectra.

Several embodiments are enumerated below to describe the implementation of the present invention in detail.

Embodiment one

As shown in Figure 1, the spectral phase interference device provided by this embodiment includes: used to obtain a chirped pulse 10 and a first sub-pulse to be measured 11 and a second sub-pulse to be measured 12 with the same characteristics, and make the chirped pulse The pulse 1 acts on the first sub-pulse 11 to be measured and the second sub-pulse 12 to be measured respectively to generate the sum frequency crystal 5 of the first sum frequency pulse 13 and the second sum frequency pulse 14; The frequency pulse 13 is divided into the first sum frequency sub-pulse 15 and the second sum frequency sub-pulse 16, and the second sum frequency pulse 14 is divided into the third sum frequency sub-pulse 17 and the fourth sum frequency sub-pulse 18. Beamer 3; for superimposing the first sum-frequency sub-pulse 15 and the third sum-frequency sub-pulse 17 to generate the first phase shift mechanism of the first spectral interference pattern; for making the second sum-frequency sub-pulse pulse 16 superimposed with a fourth sum frequency sub-pulse 18 to produce a second phase shifting mechanism for a second spectral interference pattern; a spectrometer for acquiring said first spectral interference pattern and a second spectral interference pattern; The first spectral interference pattern and the second spectral interference pattern are processed to obtain the processor 19 of the characteristics of the first sub-pulse 11 to be measured or the second sub-pulse 12 to be measured; wherein, the first phase shift mechanism And the second phase-shifting mechanism respectively has the second wave that makes the first sum-frequency sub-pulse 15 and the second sum-frequency sub-pulse 16 or makes the third sum-frequency sub-pulse 17 and the fourth sum-frequency sub-pulse 18 produce π phase shift plate 22 and a third wave plate 23. In this way, two spectral interference patterns with complementary interference fringes can be obtained conveniently. In data processing, it is no longer necessary to use a time window to filter out the DC flow, thereby eliminating the influence of the time overlap of the DC flow and the AC flow on the measurement results, which greatly improves the measurement results. Improved measurement accuracy. Therefore, the spectral phase interference device is widely used in various ultrashort optical pulse electric field direct reconstruction systems, and is especially suitable for measuring ultrashort pulse time/spectral characteristics with complex spectral shapes or narrow spectra.

In order to obtain the chirped pulse 10 and the first sub-pulse to be measured 11 and the second sub-pulse to be measured 12 with the same characteristics, the spectral phase interference device further includes: for receiving the pulse to be measured 20 and dividing it into reflected pulses 24 and the first beam splitter 1 of the transmitted pulse 25; the disperser 6 for expanding the transmitted pulse 25 and making it a chirped pulse 10; for dividing the reflected pulse 24 into the first beam splitter to be measured a second beam splitter 2 for the sub-pulse 11 and the second sub-pulse 12 to be measured; and a first wave plate 21 for adjusting the polarization direction of the chirped pulse 10 . Wherein, the first wave plate 21 rotates the polarization direction of the chirped pulse 10 projected thereon by 90° before emitting it.

This embodiment is mainly used for single pulse measurement, and the first wave plate 21 , the second wave plate 22 and the third wave plate 23 are all half-wave plates. It should be noted that half-wave plates (phase retarders), as a commonly used polarizing device, can be made of various artificial or natural birefringent crystals, and are often used to change the polarization state of the incident beam. The half-wave plate can make the o-light and e-light propagating in it produce a relative phase shift of π, which can rotate the polarization plane of the incident linearly polarized light by a specific angle, and is often used as a polarization control in the field of laser technology device. If a beam of linearly polarized light is incident on a half-wave plate, the angle between the polarization plane of the beam and the slow axis of the half-wave plate is φ (such as 45°). The slow axis is rotated by 2φ (such as 90°) for the symmetrical axis, as shown in Figure 2. In this embodiment, the included angle between the polarization plane of the chirped pulse beam incident on the first wave plate 21 and the slow axis of the wave plate is 45°. The angle between the first sum-frequency sub-pulse 15 and the slow axis of the second wave plate 22 is 0° or 90°, and the angle between the second sum-frequency sub-pulse 16 and the slow axis of the third wave plate 23 is 90° or 0°.

In addition, the spectral phase interference device may further include: a first pulse delayer 31 for adjusting the relative time delay between the first sub-pulse 11 to be measured and the second sub-pulse 12 to be measured, and a first pulse delayer 31 for adjusting the The second pulse delayer 32 for the relative time delay between the first sum frequency pulse 13 and the second sum frequency pulse 14 is described. When the pulse 20 to be measured is about 10 femtoseconds, the pulse 20 to be measured is divided into two beams by the beam splitter used as the first beam splitter 1, one of which is a reflected pulse 24, and the other is a reflected pulse 24. One beam is transmitted pulses 25 . The transmitted pulse 25 is stretched by the disperser 6 into a chirped pulse 10 with a time width between 300 femtoseconds and 800 femtoseconds. The reflected pulse 24 is equally divided into two pulses by the second beam splitter 2, wherein one pulse is the first sub-pulse 11 to be measured, and the other is the second sub-pulse 12 to be measured. The width, shape and The characteristics such as phase are the same. The first sub-pulse to be measured 11 and the second sub-pulse to be measured 12 are incident on the nonlinear sum-frequency crystal 5 together with the chirped pulse 10 to generate a first sum-frequency pulse 13 and a second sum-frequency pulse 14 . Wherein, the nonlinear sum frequency crystal 5 is a β-BBO crystal with a thickness of about tens of microns, and adopts the second type of phase matching. In the sum-frequency process, the chirped pulse 10 is e-light, and the first sub-pulse 11 to be measured and the second sub-pulse 12 to be measured are both o-light.

Here, the center wavelength difference between the first sum frequency pulse 13 and the second sum frequency pulse 14 is about 2.5 nanometers by adjusting the first pulse delayer 31 . The two sum-frequency pulses are then projected into the third beam splitter 3 in parallel, and each is divided into two beams; that is, the first sum-frequency pulse 13 is reflected and transmitted by the third beam splitter 3 and divided into two beams. The first sum-frequency sub-pulse 15 and the second sum-frequency sub-pulse 16; similarly, the second sum-frequency pulse 14 is divided into the third sum-frequency sub-pulse 17 and the third sum-frequency sub-pulse 17 after being transmitted through the third beam splitter 3 The fourth sum frequency sub-pulse 18 . Usually, the third beam splitter 3 is preferably a 50:50 non-polarizing cube beam splitter. Wherein, the first sum-frequency sub-pulse 15 and the second sum-frequency sub-pulse 16 respectively pass through a broadband half-wave plate of light with a wavelength of 400 nanometers (ie, the second wave plate 22 and the third wave plate 23) and then enter the first spectrometer 41 and a second spectrometer 42. The third sum-frequency sub-pulse 17 and the fourth sum-frequency sub-pulse 18 are directly received by the first spectrometer 41 and the second spectrometer 42 respectively. At this time, the first sum-frequency sub-pulse 15 is superimposed with the third sum-frequency sub-pulse 17 to generate the first spectral interference pattern; the second sum-frequency sub-pulse 16 is superimposed with the fourth sum-frequency sub-pulse 18 to generate the first sum-frequency sub-pulse 18 Two spectral interference patterns.

The relative time delay between the first sum-frequency pulse 13 and the second sum-frequency pulse 14 can be adjusted by the second pulse delayer 32, so that the density of the spectral interference ring measured by each spectrometer is appropriate. Wherein, the spectral resolution of the first spectrometer 41 and the second spectrometer 42 needs to be high enough (for example, 0.02 nm). In addition, the sum-frequency sub-pulse passing through the second wave plate 22 is made to be o light, the sum-frequency sub-pulse passing through the third wave plate 23 is made to be e light; or the sum-frequency sub-pulse passing through the second wave plate 23 is made to be e light; The sum-frequency sub-pulse of the wave plate 22 is e-light, and the sum-frequency sub-pulse transmitted through the third wave plate 23 is o-light. That is, if the first sum frequency sub-pulse 15 is o light, then the second sum frequency sub pulse 16 is e light; if the third sum frequency sub pulse 17 is o light, then the fourth sum frequency sub pulse The sub-pulse 18 is e-light; if the first sum-frequency sub-pulse 15 is e-light, then the second sum-frequency sub-pulse 16 is o-light; if the third sum-frequency sub-pulse 17 is e-light, then The fourth sum frequency sub-pulse 18 is o light.

Assuming that the spectral interference ring measured by the first spectrometer 41 is

D ₁ =|E _1A (ω)| ² +|E _2A (ω-Ω)| ² +2|E _1A (ω)E _2A (ω-Ω)|cos[ωτ+ψ(ω)-ψ(ω -Ω) (1)

Wherein E represents the electric field, τ is the time delay between the first sum frequency pulse 13 and the second sum frequency pulse 14, and Ω is the center frequency difference between the first sum frequency pulse 13 and the second sum frequency pulse 14, And ψ represents the phase. Correspondingly, the spectral interference ring measured by the second spectrometer 42 can be expressed as

D ₂ =|E _1B (ω)| ² +|E _2B (ω-Ω)| ² -2|E _1B (ω)E _2B (ω-Ω)|cos[ωτ+ψ(ω)-ψ(ω -Ω) (2)

Because the first sum-frequency pulse 13 and the second sum-frequency pulse 14 are incident to a 50:50 non-polarizing cube beam splitter in parallel, there is

|E _1B (ω)| ² /|E _1A (ω)| ² =|E _2B (ω)| ² /|E _2A (ω)| ² =1 (3)

In practice, the splitting ratio of a non-polarizing cube beamsplitter may deviate slightly from unity. Numerically correcting this, the following result can be obtained

D ₁ -μD ₂ =4|E _1B (ω)E _2B (ω-Ω)|cos[ωτ+ψ(ω)-ψ(ω-Ω)] (4)

Obviously, the correction coefficient μ satisfies

μ|E _1B (ω)| ² =|E _1A (ω)| ² , μ|E _2B (ω-Ω)| ² =|E _2A (ω)| ² (5)

Then the spectral shear phase difference can be obtained directly from (4).

In this embodiment, the first spectrometer 41 and the second spectrometer 42 are spectrometers of the same model and specification, so as to have the same spectral response characteristics and noise characteristics. The two spectrometers acquire the data recorded on the first spectral interference ring and the second spectral interference ring synchronously in time, and store them in the processor 19 for processing by corresponding data processing software. Compared with the existing SPIDER device, this embodiment records two spectral interference rings through the two-step phase shift technology, so that the influence of DC flow on the time interception of AC flow in the existing device can be easily eliminated in data processing, which brings two Benefits in two ways:

1) When measuring ultrashort pulses with complex spectral shape or narrow spectrum (wider time), it can effectively avoid the overlapping of DC and AC quantities in the time domain. Thereby effectively widening the measurable range.

2) The selection of the AC component is no longer intercepted by the time window, but by the weighted subtraction of the spectral interference rings measured by two spectrometers with the same performance, which effectively reduces the influence of noise.

If the pulse 20 to be measured is an optical pulse of about 100 femtoseconds, the time width of the chirped pulse 10 can be about 1.5 picoseconds by adjusting the disperser 6, and the first beam splitter 1 A 50:50 width beamsplitter is sufficient. If the pulse 20 to be measured is an ultrashort pulse on the order of an optical period, then the second beam splitter 2 can be a polarization-independent non-dispersive beam splitter, which is an isosceles prism with a base angle of less than 10° , and plate a 0-degree width high-reflection film on the two waist planes, as shown in Figure 3. The aforementioned reflected pulse 24 is projected onto the two waist planes perpendicular to the bottom surface of the isosceles prism, which can be divided into the first sub-pulse 11 to be measured and the second sub-pulse 12 to be measured, and the pulse is translated along the direction perpendicular to the transmission direction of the reflected pulse 24 The isosceles prism can adjust the power ratio between the first sub-pulse to be measured 11 and the second sub-pulse to be measured 12 , which is easy to operate.

Embodiment two

As shown in Figure 4, different from Embodiment 1, the spectral phase interference device provided by this embodiment is suitable for multiple pulse measurements, and it also includes: for making the first sum frequency sub-pulse 15 and the third sum frequency sub-pulse 15 The frequency sub-pulse 17 is simultaneously transmitted/reflected, then superimposed to generate the first spectral interference pattern, and the second sum-frequency sub-pulse 16 and the fourth sum-frequency sub-pulse 18 are simultaneously reflected/transmitted, and then superimposed to generate the second spectrum The fourth beam splitter 4 of the interference pattern; for time-sharing the first sum-frequency sub-pulse 15 and the third sum-frequency sub-pulse 17, the second sum-frequency sub-pulse 16 and the fourth sum-frequency sub-pulse 18 Enters the optical chopper 7 of the fourth beam splitter 4 . If the first sum-frequency sub-pulse 15 and the third sum-frequency sub-pulse 17 are simultaneously transmitted through the fourth beam splitter 4, then the second sum-frequency sub-pulse 16 and the fourth sum-frequency sub-pulse 18 are transmitted through the fourth beam splitter 4 The fourth beam splitter 4 reflects at the same time; if the first sum frequency sub-pulse 15 and the third sum frequency sub-pulse 17 are simultaneously reflected by the fourth beam splitter 4, the second sum frequency sub-pulse 16 The fourth sum frequency sub-pulse 18 is transmitted through the fourth beam splitter 4 at the same time, and this is related to the placement position of the fourth beam splitter 4 .

Wherein, the spectrometer 40 is only one, and is used to receive the first spectral interference pattern and the second spectral interference pattern in time division. Likewise, the fourth beam splitter is preferably a 50:50 non-polarizing cube beam splitter. It should be understood that the spectrometer 40 works synchronously with the optical chopper 7 to achieve better results. In addition, the optical chopper 7 is located between the third beam splitter 3 and the fourth beam splitter 4 . Here, a spectrometer is omitted, and the noise characteristics introduced by the same spectrometer 40 to different received spectral interference rings are the same, which is more conducive to improving the measurement accuracy.

Embodiment three

As shown in Figure 5, different from the second embodiment, the spectral phase interference device provided by this embodiment also includes: for making the first sum-frequency sub-pulse 15 and the third sum-frequency sub-pulse 17 return along the original optical path To the third beam splitter 3, superposed after transmission/reflection from the third beam splitter 3, to generate the first mirror 51 of the first spectral interference pattern; for making the second sum frequency The sub-pulse 16 and the fourth sum-frequency sub-pulse 18 return to the third beam splitter 3 along the original optical path, and are superimposed after reflection/transmission from the third beam splitter 3 to generate the second spectral interference pattern The second reflecting mirror 52; and for making the first sum-frequency sub-pulse 15 and the third sum-frequency sub-pulse 17, the second sum-frequency sub-pulse 16 and the fourth sum-frequency sub-pulse 18 time-divisionally projected to the first sum-frequency sub-pulse 15 An optical chopper 7 for a mirror 51 and a second mirror 52. Wherein, the optical chopper 7 is located between the third beam splitter 3 and the first reflector 51 and the second reflector 52, and is parallel to each other. Of course, both the second wave plate 22 and the third wave plate 23 should be quarter wave plates. Here, the fourth beam splitter described in the second embodiment is omitted, and the structure is simple and the cost is lower.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (10)

1. a spectrum phase interference device, is characterized in that, comprising:

For obtaining chirped pulse and identical the first subpulse to be measured of characteristic and the second subpulse to be measured, and make described chirped pulse act on the first subpulse to be measured and the second subpulse to be measured respectively, with produce first and frequently pulse and second and pulse frequently with frequency crystal;

For described first and frequently pulse are divided into first and frequently subpulse and second and frequently subpulse, described second and pulse be frequently divided into the 3rd and subpulse and the 4th and the 3rd beam splitter of subpulse frequently frequently;

Superpose with the 3rd and frequency subpulse, to produce the first-phase moving mechanism of the first spectral interference pattern with frequency subpulse for making described first;

Superpose with the 4th and frequency subpulse, to produce the second-phase moving mechanism of the second spectral interference pattern with frequency subpulse for making described second;

For obtaining the spectrometer of described first spectral interference pattern and the second spectral interference pattern; And

For processing described first spectral interference pattern and the second spectral interference pattern, to obtain the processor of the characteristic of described first subpulse to be measured or the second subpulse to be measured;

Wherein, described first-phase moving mechanism and second-phase moving mechanism have respectively and make first and frequently subpulse and second and subpulse or make the 3rd and subpulse and the 4th and frequently produce the second wave plate and the 3rd wave plate of π or-π phase shift between subpulse frequently frequently.

2. spectrum phase interference device as claimed in claim 1, it is characterized in that, described spectrum phase interference device also comprises:

For receiving pulse to be measured and making it to be divided into the first beam splitter of reflected impulse and transmitted pulse;

For carrying out broadening to described transmitted pulse and making it to become the dispersor of chirped pulse;

For described reflected impulse being divided into the second beam splitter of the first subpulse to be measured and the second subpulse to be measured; And

For adjusting the first wave plate of described chirped pulse polarization direction.

3. spectrum phase interference device as claimed in claim 2, it is characterized in that, when described pulse to be measured is single pulse, described first wave plate, the second wave plate and the 3rd wave plate are half-wave plate; Described spectrometer is two, and its model, specification are all identical, is respectively used to receive described first spectral interference pattern and the second spectral interference pattern.

4. spectrum phase interference device as claimed in claim 2, it is characterized in that, when described pulse to be measured is multiple pulses, described spectrum phase interference device also comprises:

For making described first and frequently subpulse and the 3rd and subpulse transmission/reflection simultaneously frequently, then superpose and produces described first spectral interference pattern, described second and frequency subpulse and the 4th with reflection/transmission while of frequency subpulse, then superpose the 4th beam splitter producing described second spectral interference pattern; And

For make described first and frequently subpulse with the 3rd and frequently subpulse, described second and frequently subpulse and the 4th and the timesharing of frequency subpulse enter the optical chopper of described 4th beam splitter;

Wherein said spectrometer is only one, receives described first spectral interference pattern and the second spectral interference pattern for timesharing; Described optical chopper is between the 3rd beam splitter and the 4th beam splitter; Described first wave plate, the second wave plate and the 3rd wave plate are half-wave plate.

5. spectrum phase interference device as claimed in claim 4, it is characterized in that, described 3rd beam splitter and the 4th beam splitter are the unpolarized cube splitter of 50:50.

6. spectrum phase interference device as claimed in claim 2, it is characterized in that, when described pulse to be measured is multiple pulses, described spectrum phase interference device also comprises:

For making described first to be back to described three beam splitter with frequency subpulse along original optical path with frequency subpulse and the 3rd, superpose after described 3rd beam splitter transmission/reflection, to produce the first catoptron of described first spectral interference pattern;

For making described second to be back to described three beam splitter with frequency subpulse along original optical path with frequency subpulse and the 4th, superpose after described three beam splitter reflection/transmission, to produce the second catoptron of described second spectral interference pattern;

For make described first and frequently subpulse with the 3rd and frequently subpulse, described second and frequently subpulse and the 4th and the timesharing of frequency subpulse be projected to the optical chopper of the first catoptron, the second catoptron;

Wherein, described spectrometer is only one, receives described first spectral interference pattern and the second spectral interference pattern for timesharing; Described optical chopper is between the 3rd beam splitter and first, second catoptron, and described first wave plate is half-wave plate, and the second wave plate and the 3rd wave plate are quarter-wave plate.

7. the spectrum phase interference device according to any one of claim 1 ~ 6, is characterized in that, described spectrum phase interference device comprises further:

For regulating the first pulse delay unit of the relative time-delay between described first subpulse to be measured and the second subpulse to be measured; And

For regulating described first and frequently pulse and second and the second pulse delay unit of the interpulse relative time-delay of frequency.

8. spectrum phase interference device as claimed in claim 7, it is characterized in that, when described pulse to be measured is the ultrashort pulse of photoperiod magnitude, described second beam splitter is polarization-independent non-dispersive beam splitter, it is the girdle prism such as grade that base angle is less than 10 °, in two waist planes platings, 0 degree of width high-reflecting film; Described reflected impulse is projected to two waist planes perpendicular to waiting bottom surface of girdle prism, carries out beam splitting with this.

9. spectrum phase interference device as claimed in claim 7, is characterized in that, being incident to chirped pulse that is described and crystal frequently is e light, and described first subpulse to be measured and the second subpulse to be measured are o light;

If is o light through described second wave plate with frequency subpulse, then make to be e light through described 3rd wave plate with frequency subpulse; If or be e light through described second wave plate with frequency subpulse, then make to be o light through described 3rd wave plate with frequency subpulse.

10. one kind adopts the direct reconfiguration system of ultrashort light pulse electric field of the spectrum phase interference device according to any one of claim 1 ~ 9.