Terahertz space-time distribution single-shot measuring device, measuring method and measuring system thereof

Abstract

The invention provides a terahertz spatial-temporal distribution single-shot measuring device, a measuring method thereof and a measuring system. The terahertz spatial-temporal distribution single-shot measuring device comprises a probe light modulation assembly, an electro-optical crystal and an imaging assembly. The probe light debugging system adjusts the pulse width and size of probe light, the terahertz at the electro-optical crystal and the probe light act to modulate the polarization of the probe light, and the imaging assembly performs imaging on the probe light at the electro-optical crystal. During use, probe light is modulated by the probe light modulation assembly and then enters the electro-optical crystal in a time-space synchronization manner with terahertz, and the imaging assembly images probe light spots with different wavelengths and different polarizations respectively. The spatial distribution and time domain waveform of terahertz can be obtained by comparing the change of the light spot of the probe when the terahertz exists or not. The device is simple in structure, easy to implement and capable of measuring the space-time distribution of terahertz under the single-shot condition.

Description

Technical Field

[0001] The present invention belongs to the field of terahertz measurement, and in particular relates to a terahertz spatiotemporal distribution single-shot measurement device, a measurement method and a measurement system thereof. Background Art

[0002] Terahertz (THz) generally refers to electromagnetic waves with a frequency range of 0.1THz to 10THz (corresponding to a wavelength range of 3000μm to 30μm), which is between the microwave band and the infrared band. Due to its unique frequency range, it has some unique characteristics and is of great significance in security inspection, communication, materials, biology, etc. With the vigorous development of various terahertz sources in recent decades, especially with the continuous development of ultrafast lasers, various terahertz sources based on ultrafast lasers have continued to emerge, and the corresponding demand for terahertz measurement solutions has also continued to increase. At present, there are two main solutions for measuring the time domain waveform of terahertz sources based on ultrafast lasers: electro-optical sampling and Michelson interference. Both solutions require multiple scans to obtain the terahertz time domain waveform. However, since some terahertz sources rely on complex laser devices, have low operating frequencies and relatively poor repeatability, it is almost impossible to obtain their time domain waveforms through traditional scanning solutions in experiments. In recent years, in order to measure the time domain waveform of low-repetition-rate terahertz sources, a variety of single-shot terahertz time domain waveform measurement solutions have emerged. For terahertz sources driven by strong lasers, spectral coding schemes and spatial coding schemes are single-shot measurement schemes that have emerged. However, these schemes can only measure terahertz time-domain waveforms in a single shot, and cannot measure terahertz spatial distributions. Even through improved scheme design, at most, only single-shot measurement of one-dimensional spatial distribution can be achieved. That is, these schemes can achieve one-dimensional time resolution and one-dimensional spatial resolution at most through design, and single-shot measurement of terahertz two-dimensional spatial distribution is still not possible. For single-shot detection of terahertz spatial distribution, terahertz cameras are currently mainly relied on, but terahertz cameras have no time resolution capability and cannot measure terahertz time-domain waveforms. In summary, there is still a lack of single-shot detection schemes that can simultaneously detect terahertz two-dimensional spatial distribution and one-dimensional time distribution in one shot. Summary of the invention

[0003] Therefore, the purpose of the present invention is to overcome the defects in the prior art and provide a terahertz spatiotemporal distribution single-shot measurement device, a measurement method and a measurement system thereof to achieve single-shot measurement of terahertz two-dimensional spatial distribution and time domain waveform.

[0004] Before describing the technical solution of the present invention, the terms used in this article are defined as follows:

[0005] The term "OAP" means: Off-Axis Parabolic Mirror.

[0006] The term "probe light" refers to a short pulse of femtosecond laser light with low energy used for terahertz measurements.

[0007] The term "Offner stretcher" refers to a spectrum stretching system consisting of a concave mirror, a convex mirror and a grating.

[0008] To achieve the above-mentioned object, the first aspect of the present invention provides a terahertz spatiotemporal distribution single-shot measurement device, the terahertz spatiotemporal distribution single-shot measurement device comprising: a probe light modulation component, an electro-optical crystal and an imaging component; wherein,

[0009] The electro-optic crystal is located between the probe light modulation component and the imaging component;

[0010] The probe light modulation component performs temporal and spatial modulation on the probe light, the electro-optical crystal performs electro-optical sampling, and the imaging component measures the probe light spot.

[0011] According to the terahertz spatiotemporal distribution single-shot measurement device of the first aspect of the present invention, the probe light modulation component comprises a pulse width modulation device and a delay line;

[0012] Preferably, the probe light modulation assembly further comprises an aperture for spatially modulating the probe light.

[0013] According to the first aspect of the present invention, the terahertz spatiotemporal distribution single-shot measurement device, wherein:

[0014] The delay line is composed of a precision electric-controlled translation stage and a roof reflector;

[0015] The modulated pulse width device is selected from one or more of the following: a double grating stretcher, a dispersion glass, a quad grating stretcher, an Offner stretcher, a prism pair stretcher, and a stretching optical fiber, preferably selected from one or more of the following: a double grating stretcher, a dispersion glass, a prism pair stretcher, more preferably a double grating stretcher or a dispersion glass, most preferably a dispersion glass; and / or

[0016] The pulse width modulation device widens the short pulse width probe light;

[0017] Preferably, the iris is selected from one or more of the following: an electric variable iris, a manual variable iris, a square variable iris, and most preferably a square variable iris.

[0018] According to the first aspect of the present invention, the terahertz spatiotemporal distribution single-shot measurement device, wherein:

[0019] The electro-optical crystal is selected from one or more of the following: zinc telluride crystal, gallium phosphide crystal, zinc sulfide crystal, gallium arsenide crystal, indium sulfide crystal, gallium selenide crystal, preferably selected from one or more of the following: zinc telluride crystal, gallium phosphide crystal, gallium selenide crystal, more preferably zinc telluride crystal or gallium phosphide crystal;

[0020] The electro-optical sampling is to generate a birefringence effect when the terahertz radiation is incident on the electro-optical crystal, thereby modulating the polarization of the probe light; and / or

[0021] The delay line synchronizes the probe light and the terahertz light in time and space at the electro-optical crystal.

[0022] According to the first aspect of the present invention, the terahertz spatiotemporal distribution single-shot measurement device, wherein:

[0023] The imaging assembly comprises: a lens, a quarter wave plate, an etalon and a transmission grating; and / or

[0024] The imaging component images the probe light spot at the electro-optical crystal;

[0025] Preferably, the imaging is 1:1 imaging or reduced imaging of the probe light spot;

[0026] More preferably, the imaging is a reduced image.

[0027] According to the first aspect of the present invention, the terahertz spatiotemporal distribution single-shot measurement device, wherein:

[0028] The number of the lenses is 1 to 4, preferably 2 to 3, and more preferably 2;

[0029] The quarter wave plate is selected from one or more of the following: a broadband achromatic wave plate, a zero-order wave plate, a multi-order wave plate, preferably a broadband achromatic wave plate or a zero-order wave plate, most preferably a broadband achromatic wave plate; and / or

[0030] The etalon is selected from one or more of the following: an air gap adjustable etalon, an air gap fixed etalon, and a solid etalon, preferably selected from one or more of the following: an air gap adjustable etalon, an air gap fixed etalon, and a fused silica solid etalon, more preferably an air gap etalon or a fused silica solid etalon;

[0031] Preferably, the fused silica solid etalon is a solid etalon with 70-95% partial reflection film on both sides and a thickness of 40-60 microns, more preferably a solid etalon with 80-90% partial reflection film on both sides and a thickness of 45-55 microns, most preferably a solid etalon with 85% partial reflection film on both sides and a thickness of 50 microns; and / or

[0032] Preferably, the air gap adjustable standard is an air gap adjustable standard with 80-90% partial reflection film coated on both sides, adjustable thickness of 30μm to 100μm, and the base material is fused quartz. More preferably, the air gap adjustable standard is an air gap adjustable standard with 85% partial reflection film coated on both sides, adjustable thickness of 40μm to 60μm, and the base material is fused quartz.

[0033] According to the terahertz spatiotemporal distribution single-shot measurement device of the first aspect of the present invention, the transmission grating is located behind the etalon to separate the diffracted light components of different wavelengths in space;

[0034] Preferably, the transmission grating has a groove number of 100 to 500 lines / mm, more preferably 150 to 400 lines / mm, and most preferably 300 lines / mm.

[0035] According to the terahertz spatiotemporal distribution single-shot measurement device of the first aspect of the present invention, the imaging assembly further comprises: a prism and a camera, the prism being located in front of the camera;

[0036] Preferably, the prism splits light of different polarizations, and is more preferably selected from the following: Wollaston prism, Rochon prism, Glan-Taylor prism, laser Glan prism, further preferably Wollaston prism or Rochon prism, most preferably Wollaston prism; and / or

[0037] Preferably, the camera is a visible light band or near infrared band camera, and most preferably is an area array camera.

[0038] A second aspect of the present invention provides a single-shot measurement method, wherein the single-shot measurement method performs single-shot measurement by using the terahertz spatiotemporal distribution single-shot measurement device described in the first aspect;

[0039] Preferably, the single-shot measurement method comprises the following steps:

[0040] (1) After the probe beam is introduced into the probe light modulation component for modulation, it is incident on the electro-optical crystal in time and space synchronization with the terahertz beam and imaged by the imaging component;

[0041] (2) By comparing the changes in the light spot with the same wavelength and polarization when there is terahertz and without terahertz, the spatial distribution of the terahertz light spot can be obtained; by comparing the changes in the light spot with different wavelengths, the same polarization and the same position, the terahertz time domain information can be obtained.

[0042] A third aspect of the present invention provides a terahertz space-time distribution measurement system, which includes the terahertz space-time distribution single-shot measurement device described in the first aspect.

[0043] According to a specific embodiment of the present invention, the first aspect of the present invention provides a single-shot terahertz spatiotemporal distribution measurement device, the device comprising: a probe light modulation component, an electro-optical crystal and an imaging component; wherein:

[0044] The probe light modulation component performs pulse width, optical path and spatial modulation on the probe light, the electro-optical crystal performs an electro-optical sampling process, and then the imaging component detects the probe light spot.

[0045] The probe light modulation part pulse width modulation adopts a double grating stretcher or a dispersion glass, preferably a double grating stretcher, to stretch the short pulse width of tens of femtoseconds probe light to hundreds of femtoseconds to picoseconds. Different spectral components in the probe light experience different optical path lengths, so different parts of the probe light spectrum arrive at the electro-optical crystal at different times. The probe light optical path modulation is completed by a delay line composed of a precision electrically controlled translation stage and a roof reflector, which can achieve time synchronization between the probe light and the terahertz to be measured at the electro-optical crystal.

[0046] The electro-optic crystal may be a zinc telluride crystal or a gallium phosphide crystal commonly used in terahertz time-domain spectroscopy measurement. When terahertz is incident on the electro-optic crystal, a birefringence effect is generated to modulate the polarization of the probe light, which is the traditional terahertz electro-optic sampling process.

[0047] The imaging assembly is an optical path and its elements for imaging the light spot modulated by terahertz. The imaging assembly can be composed of a single-lens imaging assembly or a plurality of lenses to image the probe light spot at the electro-optical crystal. The probe light spot can be imaged 1:1 or reduced, preferably reduced. In the imaging assembly, the object plane is the surface of the electro-optical crystal, and the array camera is placed on the image plane. After modulation, the probe light first passes through a quarter-wave plate, preferably a broadband achromatic wave plate. The probe light is modulated using an etalon at an appropriate position in the imaging optical path to select the probe light of a specific wavelength. A transmission grating is placed after the etalon in the imaging optical path to separate the diffracted light components of different wavelengths in space. During imaging, a camera is used to image the diffracted light components of different wavelengths. A Wollaston prism is used in front of the camera to separate the two different polarization components of the probe light.

[0048] The etalon in the present invention can be selected from an etalon based on an air gap or a solid etalon. Preferably, it is an adjustable etalon based on an air gap, which can flexibly adjust the intervals between adjacent frequency components in the experiment, thereby changing the sampling rate of the system. The etalon is selected from one or more of the following: an air gap adjustable etalon, an air gap fixed etalon, and a solid etalon (the specific materials can be various, such as: fused quartz, N-BK7 glass, calcite, etc.).

[0049] The second aspect of the present invention provides a single-shot measurement method for terahertz spatiotemporal distribution, wherein the method uses the device described in the first aspect to perform single-shot measurement of terahertz spatiotemporal distribution;

[0050] Preferably, the method comprises the following steps:

[0051] The probe beam is introduced into the probe light modulation component for shape, pulse width and optical path modulation, and then incident on the electro-optical crystal in time and space overlap with the focused terahertz beam. The birefringence effect generated by the terahertz modulates the polarization of the probe light, and the modulated probe light is imaged by the imaging component. The spatial distribution of terahertz can be extracted by comparing the intensity changes of the probe light spot in the same polarization state with or without terahertz. The time domain information of terahertz can be obtained by comparing the intensity changes of the probe light at the same spot position in different spectral components with or without terahertz.

[0052] According to another specific embodiment of the present invention, the terahertz spatiotemporal distribution single-shot measurement device of the present invention comprises: a probe light modulation component, an electro-optical crystal and an imaging component; wherein:

[0053] The probe light modulation component performs temporal and spatial modulation on the probe light, the electro-optical crystal performs terahertz modulation on the polarization of the probe light, and the imaging component measures the probe light spot.

[0054] In the imaging assembly, an etalon and a grating are used to image the probe light spots of different wavelengths respectively.

[0055] The etalon is a solid etalon or an air gap etalon; preferably, the solid etalon is a solid etalon with 85% partial reflection film on both sides and a thickness of 50 microns; the gas etalon is an adjustable etalon.

[0056] A transmission grating is used for light splitting. Preferably, the transmission grating has 300 lines / mm.

[0057] The imaging component is an imaging component composed of a single lens or a lens group.

[0058] During detection, a Wollaston prism or a Rochon prism is used to split light of different polarizations. Preferably, a large-aperture Wollaston prism is used.

[0059] Use visible light or near-infrared cameras for imaging.

[0060] The present invention also provides a terahertz spatiotemporal distribution single-shot measurement method, the method comprising the following steps:

[0061] The probe beam is modulated by the probe light modulation component and incident on the electro-optical crystal synchronously with the terahertz space and time. The imaging component performs imaging. By comparing the changes in the spot of the same wavelength and polarization with and without terahertz, the spatial distribution of the terahertz spot can be obtained. By comparing the changes in the spot of different wavelengths, the same polarization and the same position, the terahertz time domain information can be obtained.

[0062] The present invention also provides a terahertz space-time distribution measurement system, which comprises a Hertz space-time distribution single-shot measurement device.

[0063] The imaging assembly of the present invention comprises in sequence: a lens, a quarter wave plate, an etalon, a transmission grating, a prism and a camera.

[0064] The present invention provides a single-shot measurement device for terahertz spatiotemporal distribution, including a probe light modulation component, an electro-optical crystal and an imaging component. The probe light debugging system adjusts the probe light pulse width and size. The terahertz and probe light at the electro-optical crystal act to modulate the polarization of the probe light. The imaging component images the probe light at the electro-optical crystal. When in use, the probe light is modulated by the probe light modulation component and incident on the electro-optical crystal synchronously with the terahertz spatiotemporally. The imaging component images probe light spots of different wavelengths and different polarizations respectively. The spatial distribution and time domain waveform of the terahertz can be obtained by comparing the changes in the probe light spot with and without terahertz. The device of the present invention has a simple structure and is easy to implement. It can measure the spatiotemporal distribution of terahertz under single-shot conditions.

[0065] The terahertz spatiotemporal distribution single-shot measurement device of the present invention can have but is not limited to the following beneficial effects:

[0066] 1. The present invention can overcome the bottleneck in the prior art and can simultaneously detect the measurement of the two-dimensional spatial distribution and time domain waveform of terahertz in one shot, that is, the spatial and temporal distribution of terahertz can be measured under single-shot conditions. Compared with the traditional single-shot terahertz single-shot time domain measurement technology, this solution realizes the measurement of two-dimensional terahertz spatial distribution. Compared with two-dimensional distribution detection solutions such as terahertz cameras, this solution can measure the terahertz time domain waveform in a single shot.

[0067] 2. The structure is relatively simple and easy to implement.

[0068] 3. The present invention can be applied to the field of terahertz measurement and can realize single-shot measurement of terahertz spatiotemporal distribution. In the field of strong-field terahertz research, it can more efficiently and comprehensively characterize the spatiotemporal distribution of terahertz radiation than existing solutions. It has great application prospects in the study of strong-field terahertz characteristics and condensed matter physics driven by strong-field terahertz. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein:

[0070] Figure 1 The structure diagram of the terahertz spatiotemporal distribution single-shot measurement device of the present invention is shown.

[0071] Figure 2 A schematic diagram of the optical path layout of the probe light modulation assembly is shown.

[0072] Figure 3 A schematic diagram of the optical path layout of the imaging component is shown.

[0073] Figure 4The probe spot image expected in Example 2 and the terahertz time domain waveform extracted therefrom are shown; wherein, Figure 4 A shows the expected probe spot image; Figure 4 B shows the terahertz time-domain waveform extracted from the probe spot pattern.

[0074] Description of reference numerals:

[0075] 1. Probe light modulation component; 2. Electro-optical crystal; 3. Imaging component; 4 terahertz; 11. Dispersion glass; 12. Delay line; 31. Imaging lens; 32. Achromatic quarter-wave plate; 33. Etalon 34. Transmission grating; 35. Wollaston prism 36. Area array camera. DETAILED DESCRIPTION

[0076] The present invention is further described below by means of specific examples. However, it should be understood that these examples are only used for more detailed and specific description and should not be understood as limiting the present invention in any form.

[0077] This section generally describes the materials and test methods used in the experiments of the present invention. Although many materials and operating methods used to achieve the purpose of the present invention are well known in the art, the present invention is still described as detailed as possible. It is clear to those skilled in the art that in the context, if not specifically stated, the materials and operating methods used in the present invention are well known in the art.

[0078] Example 1

[0079] This embodiment is used to illustrate the structure of the terahertz spatiotemporal distribution single-shot measurement device of the present invention.

[0080] like Figure 1 , Figure 2 and Figure 3 As shown, the terahertz spatiotemporal distribution single-shot measurement device of the present invention includes a probe light modulation component 1, an electro-optical crystal 2 and an imaging component 3.

[0081] Wherein, the probe light modulation component is as follows Figure 2 As shown, dispersion glass is used to modulate the pulse width of the probe light, and the short pulse width of tens of femtoseconds of the probe light is widened to the order of hundreds of femtoseconds to picoseconds; then a square variable aperture is used to modulate the spatial size of the light spot, and the delay line composed of a roof reflector and a precision electric translation stage is used to modulate the optical path of the probe light, so that the probe light and the terahertz to be measured can be time synchronized at the electro-optical crystal.

[0082] The electro-optical crystal may be a zinc telluride crystal or a gallium phosphide crystal commonly used in terahertz time-domain spectroscopy measurement. When terahertz is incident on the electro-optical crystal, a birefringence effect is generated, modulating the polarization of the probe light, which is the traditional terahertz electro-optical sampling process. The electro-optical crystal used in this embodiment is a zinc telluride crystal.

[0083] The imaging component is an optical path and its components for imaging the light spot modulated by terahertz. In the imaging component, the object plane is the surface of the electro-optical crystal, and the area array camera is placed on the image plane. Figure 3 As shown, a single lens 31 images the probe light at the electro-optical crystal 2. The probe light spot can be imaged 1:1 or reduced, and this embodiment is reduced. An achromatic quarter-wave plate 32 is first placed in the imaging light path, and then frequency selection and spectral splitting are performed through an etalon 33 and a transmission grating 34 to separate the diffraction spots of different frequencies in space and image them to different positions. Finally, a Wollaston prism 35 and a surface array camera 36 are used to image the two probe lights with different polarizations.

[0084] Example 2

[0085] This embodiment is used to illustrate the measurement method and results of the terahertz spatiotemporal distribution single-shot measurement device of the present invention.

[0086] This embodiment uses the terahertz spectrum single-shot measurement device of Embodiment 1 for measurement, wherein:

[0087] The probe light comes from a femtosecond laser with a central wavelength of 800nm ​​and a pulse width of about 30 femtoseconds. The probe light modulation component uses SF57 glass to broaden the probe light, uses a variable square aperture to modulate the spot to about 1.5mm horizontally, and uses a delay line to control the optical path, so that the probe light can be synchronized with the terahertz in time and space at the electro-optical crystal 2.

[0088] The terahertz source used in the test can be a terahertz source based on a lithium niobate tilted wavefront solution, using an OAP with a focal length of 50.8 mm and a 3 mm central aperture to focus the terahertz, and the probe light passes through the small hole of the OAP and the terahertz is synchronized in time and space at the terahertz focus. For this terahertz source, the electro-optical crystal 2 of this embodiment uses a zinc telluride crystal with a thickness of 1 mm.

[0089] The lens used in the imaging component 3 is an achromatic lens with a focal length of 600mm, an object distance of 1500mm, and an image distance of 1000mm; the material of the etalon used is fused quartz, with a thickness of 50um and 85% partial reflection film on both sides; the achromatic wave plate used is an achromatic quarter wave plate available for wavelengths of 650nm to 1100nm; the grating used is a transmission grating for the 800nm ​​band, with a line density of 300 lines / mm. A scientific camera or an industrial camera can be used for detection, and a large-array scientific camera is selected in this embodiment.

[0090] When in use, the probe light is first modulated in time and space by the probe light modulation component 1, and then incident on the electro-optical crystal 2 in time and space synchronization with the terahertz to be measured. The imaging component 3 is used to image the probe light spot at the electro-optical crystal 2, and the probe light intensity distribution diagram is collected. By comparing the intensity changes of each wavelength and each polarization probe light with and without terahertz, the terahertz spatial distribution can be obtained. By comparing the same position in the probe light of each wavelength, the time domain change of terahertz can be obtained. The results are as follows: Figure 4 shown.

[0091] Figure 4 The probe spot image expected in Example 2 and the terahertz time domain waveform extracted therefrom are shown; wherein, Figure 4 A shows the expected probe spot image; Figure 4 B shows the terahertz time domain waveform extracted from the probe spot pattern. Figure 4 As shown in the figure, the different horizontal parts of the picture are the probe light signals at different times, and the upper and lower parts are the horizontally polarized and vertically polarized probe light signals respectively. The spatial distribution of the probe light signal at each moment can reflect the spatial distribution of the terahertz focal spot at that moment (such as Figure 4 By taking the characteristic points in the terahertz signal (points at the same position at every moment), we can get the terahertz time domain waveform (as shown in the black dashed box in A). Figure 4 B).

[0092] Although the present invention has been described to a certain extent, it is obvious that appropriate changes in various conditions can be made without departing from the spirit and scope of the present invention. It is understood that the present invention is not limited to the embodiments described, but belongs to the scope of the claims, which includes equivalent replacements of each factor described.

Claims

1. A terahertz spatiotemporal distribution single-shot measurement device, characterized in that: The terahertz spatiotemporal distribution single-shot measurement device comprises: a probe light modulation component, an electro-optical crystal and an imaging component; wherein, The electro-optic crystal is located between the probe light modulation component and the imaging component; The probe light modulation component performs temporal and spatial modulation on the probe light, the electro-optical crystal performs electro-optical sampling, and the imaging component measures the probe light spot.

2. The terahertz spatiotemporal distribution single-shot measurement device according to claim 1, characterized in that: The probe light modulation component includes a pulse width modulation device and a delay line; Preferably, the probe light modulation assembly further comprises an aperture for spatially modulating the probe light.

3. The terahertz spatiotemporal distribution single-shot measurement device according to claim 1 or 2, characterized in that: The delay line is composed of a precision electric-controlled translation stage and a roof reflector; The modulated pulse width device is selected from one or more of the following: a double grating stretcher, a dispersion glass, a quad grating stretcher, an Offner stretcher, a prism pair stretcher, and a stretching optical fiber, preferably selected from one or more of the following: a double grating stretcher, a dispersion glass, a prism pair stretcher, more preferably a double grating stretcher or a dispersion glass, most preferably a dispersion glass; and / or The pulse width modulation device widens the short pulse width probe light; Preferably, the iris is selected from one or more of the following: an electric variable iris, a manual variable iris, a square variable iris, and most preferably a square variable iris.

4. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 3, characterized in that: The electro-optical crystal is selected from one or more of the following: zinc telluride crystal, gallium phosphide crystal, zinc sulfide crystal, gallium arsenide crystal, indium sulfide crystal, gallium selenide crystal, preferably selected from one or more of the following: zinc telluride crystal, gallium phosphide crystal, gallium selenide crystal, more preferably zinc telluride crystal or gallium phosphide crystal; The electro-optical sampling is to generate a birefringence effect when the terahertz radiation is incident on the electro-optical crystal, thereby modulating the polarization of the probe light; and / or The delay line synchronizes the probe light and the terahertz light in time and space at the electro-optical crystal.

5. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 4, characterized in that: The imaging assembly comprises: a lens, a quarter wave plate, an etalon and a transmission grating; and / or The imaging component images the probe light spot at the electro-optical crystal; Preferably, the imaging is 1:1 imaging or reduced imaging of the probe light spot; More preferably, the imaging is a reduced image.

6. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 5, characterized in that: The number of the lenses is 1 to 4, preferably 2 to 3, and more preferably 2; The quarter wave plate is selected from one or more of the following: a broadband achromatic wave plate, a zero-order wave plate, a multi-order wave plate, preferably a broadband achromatic wave plate or a zero-order wave plate, most preferably a broadband achromatic wave plate; and / or The etalon is selected from one or more of the following: an air gap adjustable etalon, an air gap fixed etalon, and a solid etalon, preferably selected from one or more of the following: an air gap adjustable etalon, an air gap fixed etalon, and a fused silica solid etalon, more preferably an air gap etalon or a fused silica solid etalon; Preferably, the fused silica solid etalon is a solid etalon with 70-95% partial reflection film on both sides and a thickness of 40-60 microns, more preferably a solid etalon with 80-90% partial reflection film on both sides and a thickness of 45-55 microns, most preferably a solid etalon with 85% partial reflection film on both sides and a thickness of 50 microns; and / or Preferably, the air gap adjustable standard is an air gap adjustable standard with 80-90% partial reflection film coated on both sides, adjustable thickness of 30μm to 100μm, and the base material is fused quartz. More preferably, the air gap adjustable standard is an air gap adjustable standard with 85% partial reflection film coated on both sides, adjustable thickness of 30μm to 100μm, and the base material is fused quartz.

7. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 6, characterized in that: The transmission grating is located behind the etalon to separate the diffracted light components of different wavelengths in space; Preferably, the transmission grating has a groove number of 100 to 500 lines / mm, more preferably 150 to 400 lines / mm, and most preferably 300 lines / mm.

8. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 7, characterized in that: The imaging assembly further comprises: a prism and a camera, wherein the prism is located in front of the camera; Preferably, the prism splits light of different polarizations, and is more preferably selected from the following: Wollaston prism, Rochon prism, Glan-Taylor prism, laser Glan prism, further preferably Wollaston prism or Rochon prism, most preferably Wollaston prism; and / or Preferably, the camera is a visible light band or near infrared band camera, and most preferably is an area array camera.

9. A single-shot measurement method, characterized in that: The single-shot measurement method performs single-shot measurement by using a terahertz spatiotemporal distribution single-shot measurement device as described in any one of claims 1 to 8; Preferably, the single-shot measurement method comprises the following steps: (1) After the probe beam is introduced into the probe light modulation component for modulation, it is incident on the electro-optical crystal in time and space synchronization with the terahertz beam and imaged by the imaging component; (2) By comparing the changes in the light spot with the same wavelength and polarization when there is terahertz and without terahertz, the spatial distribution of the terahertz light spot can be obtained; by comparing the changes in the light spot with different wavelengths, the same polarization and the same position, the terahertz time domain information can be obtained.

10. A terahertz spatiotemporal distribution measurement system, characterized in that: The terahertz spatiotemporal distribution measurement system comprises the terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 8.

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