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

Abstract

This invention provides a single-shot measurement device, method, and system for terahertz spatiotemporal distribution. The single-shot terahertz spatiotemporal distribution measurement device includes: a probe light modulation component, an electro-optic crystal, and an imaging component. The probe light modulation system adjusts the pulse width and magnitude of the probe light. The interaction between the terahertz and probe light at the electro-optic crystal modulates the polarization of the probe light. The imaging component images the probe light at the electro-optic crystal. In use, the probe light, modulated by the probe light modulation component and spatiotemporally synchronized with the terahertz, is incident on the electro-optic crystal. The imaging component images probe light spots of different wavelengths and polarizations. By comparing the changes in probe light spots with and without terahertz, the spatial distribution and temporal waveform of the terahertz can be obtained. This invention has a simple structure, is easy to implement, and can measure the spatiotemporal distribution of terahertz under single-shot conditions.

Description

Technical Field

[0001] This invention belongs to the field of terahertz measurement, specifically relating to a terahertz spatiotemporal distribution single-shot measurement device, its measurement method, and measurement system. Background Technology

[0002] Terahertz (THz) generally refers to electromagnetic waves with a frequency range of 0.1 THz to 10 THz (corresponding to a wavelength range of 3000 μm to 30 μm), falling between the microwave and infrared bands. Due to its unique frequency range, it possesses some unique characteristics and holds significant importance in security inspection, communication, materials science, and biology. With the rapid development of various terahertz sources in recent decades, especially with the continuous advancement of ultrafast lasers, various terahertz sources based on ultrafast lasers have emerged, leading to a corresponding increase in the demand for terahertz measurement schemes. Currently, the measurement of the time-domain waveform of ultrafast laser-based terahertz sources mainly employs two schemes: electro-optic sampling and Michelson interferometry. Both schemes require multiple scans to obtain the terahertz time-domain waveform. However, because some terahertz sources rely on complex laser devices, operate at low frequencies, and have relatively poor repeatability, obtaining their time-domain waveforms through traditional scanning schemes is experimentally impractical. In recent years, various single-shot terahertz time-domain waveform measurement schemes have emerged to measure the time-domain waveforms of low-repetition-rate terahertz sources. For high-power laser-driven terahertz sources, spectral coding and spatial coding schemes are currently the only single-shot measurement methods available. However, these schemes can only measure the terahertz time-domain waveform in a single shot, and cannot measure the terahertz spatial distribution. Even with improved scheme design, at most only a one-dimensional spatial distribution can be measured in a single shot. That is, these schemes, through design, can achieve a maximum of one-dimensional time resolution and one-dimensional spatial resolution, but still cannot achieve single-shot measurement of the two-dimensional terahertz spatial distribution. For single-shot detection of the terahertz spatial distribution, the main method currently relies on terahertz cameras, but terahertz cameras lack time resolution and cannot measure the terahertz time-domain waveform. In summary, there is still a lack of single-shot detection schemes that can simultaneously detect the two-dimensional spatial distribution and one-dimensional time distribution of terahertz waves in a single shot. Summary of the Invention

[0003] Therefore, the purpose of this invention is to overcome the deficiencies in the prior art and provide a terahertz spatiotemporal distribution single-shot measurement device, its measurement method and measurement system, so as to realize the single-shot measurement of the two-dimensional spatial distribution and time-domain waveform of terahertz.

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

[0005] The term "OAP" refers to an off-axis parabolic mirror.

[0006] The term "probe beam" refers to a short-pulse femtosecond laser beam with relatively low energy, used for terahertz measurements.

[0007] The term "Offner broadener" refers to a spectral broadening system consisting of concave mirrors, convex mirrors, and gratings.

[0008] To achieve the above objectives, a 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-optic 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 modulates the probe light in time and space, the electro-optic crystal performs electro-optic sampling, and the imaging component measures the probe light spot.

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

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

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

[0014] The delay line consists of a precision electronically controlled translation stage and a roof reflector;

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

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

[0017] Preferably, the aperture is selected from one or more of the following: an electrically adjustable aperture, a manually adjustable aperture, a square adjustable aperture, and most preferably a square adjustable aperture.

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

[0019] The electro-optic 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-optic sampling is achieved by generating a birefringence effect when terahertz light is incident on the electro-optic crystal, modulating the polarization of the probe light; and / or

[0021] The delay line enables the probe light and terahertz to be spatiotemporally synchronized at the electro-optic crystal.

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

[0023] The imaging components include: 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-optic crystal;

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

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

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

[0028] The number of 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: broadband achromatic waveplate, zero-order waveplate, multi-order waveplate, preferably a broadband achromatic waveplate or a zero-order waveplate, and most preferably a broadband achromatic waveplate; and / or

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

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

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

[0033] According to a first aspect of the present invention, a terahertz spatiotemporal distribution single-shot measurement device is provided, wherein the transmission grating is located behind the etalon, thereby spatially separating diffracted light components of different wavelengths.

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

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

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

[0037] Preferably, the camera is a visible light band or near-infrared band camera, and most preferably 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 using the terahertz spatiotemporal distribution single-shot measurement device described in the first aspect;

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

[0040] (1) After the probe beam is modulated by the probe beam modulation component, it is incident on the electro-optic crystal in time and space synchronous with the terahertz beam and is imaged by the imaging component.

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

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

[0043] According to a specific embodiment of the present invention, a 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-optic crystal, and an imaging component; wherein:

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

[0045] The pulse width modulation of the probe light is achieved using a double-grating stretcher or dispersive glass, preferably a double-grating stretcher, to broaden the short-pulse, tens-of-femtosecond probe light to the hundreds of femtoseconds to picoseconds. Different spectral components of the probe light experience different optical path lengths, resulting in different parts of the probe light spectrum arriving at the electro-optic crystal at different times. Probe light optical path modulation is accomplished by a delay line formed by a precision electrically controlled translation stage and a roof mirror, enabling time synchronization between the probe light and the terahertz wave to be measured at the electro-optic crystal.

[0046] The electro-optic crystal can be zinc telluride crystal, gallium phosphide crystal, or other crystals commonly used in terahertz time-domain spectroscopy measurements. When terahertz light is incident on the electro-optic crystal, it produces a birefringence effect, modulating the polarization of the probe light, which is the traditional terahertz electro-optic sampling process.

[0047] The imaging assembly comprises the optical path and its components for imaging a terahertz-modulated light spot. The imaging assembly can be a single-lens imaging assembly or composed of multiple lenses to image the probe light spot at the electro-optic crystal. It can perform 1:1 imaging or reduce the size of the probe light spot, preferably reducing the size. In the imaging assembly, the object plane is the surface of the electro-optic crystal, and the area array camera is placed on the image plane. After modulation, the probe light first passes through a quarter-wave plate, preferably a broadband achromatic waveplate. An etalon is used at an appropriate position in the imaging optical path to modulate the probe light, selecting probe light of a specific wavelength. A transmission grating is placed after the etalon in the imaging optical path to spatially separate the diffracted light components of different wavelengths. 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 this invention can be either an air-gap based etalon or a solid etalon. Preferably, it is an adjustable air-gap etalon, which allows for flexible adjustment of the intervals between adjacent frequency components during experiments, thereby changing the system's sampling rate. The etalon is selected from one or more of the following: an adjustable air-gap etalon, a fixed air-gap etalon, or a solid etalon (the specific material can be various, such as fused silica, N-BK7 glass, calcite, etc.).

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

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

[0051] The probe beam is guided into a probe beam modulation component for shape, pulse width, and optical path modulation. It then coincides spatiotemporally with the focused terahertz beam and is incident on an electro-optic crystal. The birefringence effect generated by the terahertz wave modulates the polarization of the probe beam. The modulated probe beam is then imaged by an imaging component. By comparing the intensity changes of probe beam spots with the same polarization state in the presence and absence of terahertz, the spatial distribution of terahertz can be extracted. By comparing the intensity changes of probe beams at the same spot position in different spectral components with and without terahertz, the temporal information of the terahertz can be obtained.

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

[0053] The probe light modulation component modulates the probe light in time and space, the electro-optic crystal modulates the polarization of the probe light with terahertz, and the imaging component measures the probe light spot.

[0054] The imaging assembly uses an etalon and a grating to image probe spots of different wavelengths.

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

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

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

[0058] During detection, a Wollaston prism or a Roshon prism is used to separate the beams for different polarizations. A large-aperture Wollaston prism is preferred.

[0059] Imaging is performed using cameras in the visible light or near-infrared bands.

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

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

[0062] The present invention also provides a terahertz spatiotemporal distribution measurement system, which includes a Hertz spatiotemporal 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] This invention provides a single-shot measurement device for terahertz spatiotemporal distribution, comprising a probe light modulation component, an electro-optic crystal, and an imaging component. The probe light modulation system adjusts the pulse width and magnitude of the probe light. The interaction between the terahertz waves and the probe light at the electro-optic crystal modulates the polarization of the probe light. The imaging component images the probe light at the electro-optic crystal. In use, the probe light, modulated by the probe light modulation component and spatiotemporally synchronized with the terahertz waves, is incident on the electro-optic crystal. The imaging component images probe light spots of different wavelengths and polarizations. By comparing the changes in the probe light spots with and without terahertz waves, the spatial distribution and temporal waveform of the terahertz waves can be obtained. This invention has a simple structure, is easy to implement, and can measure the spatiotemporal distribution of terahertz waves under single-shot conditions.

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

[0066] 1. This invention overcomes the bottlenecks in existing technologies, enabling simultaneous detection of terahertz two-dimensional spatial distribution and time-domain waveform measurement in a single shot. In other words, it allows for the measurement of the spatiotemporal distribution of terahertz waves under single-shot conditions. Compared to traditional single-shot terahertz time-domain measurement techniques, this solution achieves two-dimensional terahertz spatial distribution measurement. Compared to two-dimensional distribution detection schemes such as terahertz cameras, this solution can measure terahertz time-domain waveforms with a single shot.

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

[0068] 3. This invention can be applied to the field of terahertz measurement, enabling single-shot measurement of the spatiotemporal distribution of terahertz. Compared with existing schemes, it can more efficiently and comprehensively characterize the spatiotemporal distribution of terahertz radiation in the field of strong-field terahertz research. It has great application prospects in the study of strong-field terahertz characteristics and the study of condensed matter physics driven by strong-field terahertz. Attached Figure Description

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

[0070] Figure 1 A structural 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 optical modulation component is shown.

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

[0073] Figure 4The image shown is an image of the probe spot expected in Example 2, and the terahertz time-domain waveform extracted from it; 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] Explanation of reference numerals in the attached figures:

[0075] 1. Probe light modulation assembly; 2. Electro-optic crystal; 3. Imaging assembly; 4. Terahertz; 11. Dispersive glass; 12. Delay line; 31. Imaging lens; 32. Achromatic quarter-wave plate; 33. Etameter; 34. Transmission grating; 35. Wollaston prism; 36. Area array camera. Detailed Implementation

[0076] The present invention will be further illustrated below with specific embodiments. However, it should be understood that these embodiments are merely for more detailed and specific illustration and should not be construed as limiting the present invention in any way.

[0077] This section provides a general description of the materials and testing methods used in the experiments of this invention. While many of the materials and methods of operation used to achieve the objectives of this invention are well known in the art, the invention is still described in as much detail as possible herein. It will be apparent to those skilled in the art that, unless otherwise stated in the context, the materials and methods of operation used in this 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-optic crystal 2, and an imaging component 3.

[0081] Among them, the probe optical modulation component is as follows Figure 2 As shown, the probe light pulse width is modulated using dispersive glass, and the short-pulse-width probe light of tens of femtoseconds is broadened 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. The optical path of the probe light is modulated by a delay line composed of a roof reflector and a precision electric translation stage, so that the probe light and the terahertz to be measured can be synchronized in time at the electro-optic crystal.

[0082] The electro-optic crystal can be zinc telluride crystal, gallium phosphide crystal, or similar materials commonly used in terahertz time-domain spectroscopy measurements. When terahertz waves are incident on the electro-optic crystal, a birefringence effect occurs, modulating the polarization of the probe light, i.e., the traditional terahertz electro-optic sampling process. The electro-optic crystal used in this embodiment is a zinc telluride crystal.

[0083] The imaging assembly comprises the optical path and its components for imaging a terahertz-modulated light spot. In the imaging assembly, the object plane is an electro-optic crystal surface, and the area array camera is placed on the image plane. The imaging assembly is as follows: Figure 3 As shown, a single lens 31 images the probe light at the electro-optic crystal 2. The probe light spot can be imaged at a 1:1 scale or reduced in size; this embodiment uses reduced image formation. An achromatic quarter-wave plate 32 is first placed in the imaging optical path. Then, frequency selection and beam splitting are performed using an etalon 33 and a transmission grating 34, spatially separating diffraction spots of different frequencies and imaging them to different positions. Finally, a Wollaston prism 35 and a planar 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 from Embodiment 1 for measurement, wherein:

[0087] The probe light originates from a femtosecond laser with a center wavelength of 800nm ​​and a pulse width of approximately 30 femtoseconds. The probe light modulation assembly uses SF57 glass to broaden the probe light, uses a variable square aperture to modulate the light spot to approximately 1.5mm laterally, and uses a delay line for optical path control, enabling the probe light to be spatiotemporally synchronized with the terahertz wave at electro-optic crystal 2.

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

[0089] The lens used in 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 etalon material used is fused silica with a thickness of 50µm and 85% partial reflective coating on both sides. The achromatic quarter-wave plate used is suitable for wavelengths from 650nm to 1100nm. The grating used is a transmission grating for the 800nm ​​band with a line density of 300 lines / mm. Detection can be performed using a scientific-grade camera or an industrial camera; this embodiment uses a large-area scientific-grade camera.

[0090] In use, the probe light is first temporally and spatially modulated by the probe light modulation component 1, and then incident on the electro-optic crystal 2 in a time-space-synchronous manner with the terahertz wave to be measured. The imaging component 3 is used to image the probe light spot at the electro-optic crystal 2, acquiring the probe light intensity distribution map. By comparing the intensity changes of each wavelength and each polarization of the probe light with and without terahertz, the spatial distribution of the terahertz can be obtained. By comparing the same positions in the probe light of each wavelength, the temporal variation of the terahertz can be obtained. The results are as follows: Figure 4 As shown.

[0091] Figure 4 The image shown is an image of the probe spot expected in Example 2, and the terahertz time-domain waveform extracted from it; 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. For example... Figure 4 As shown, the different horizontal parts of the image represent probe light signals at different times, while the upper and lower parts represent probe light signals with horizontal and vertical polarization, respectively. The spatial distribution of the probe light signal at each time moment can reflect the spatial distribution of the terahertz focal spot at that moment (e.g., Figure 4 (As shown in the black dashed box in A). By taking characteristic points (points at the same position at every moment) in the terahertz signal, the time-domain waveform of the terahertz signal can be obtained (e.g., ...). Figure 4 (as shown in B).

[0092] Although the invention has been described to a certain extent, it is apparent that appropriate variations can be made to the various conditions without departing from the spirit and scope of the invention. It is understood that the invention is not limited to the described embodiments, but falls within the scope of the claims, which include equivalent substitutions for each of the elements.

Claims

1. A terahertz spatiotemporal distribution single-shot measurement device, characterized in that, The terahertz spatiotemporal distribution single-shot measurement device includes: a probe light modulation component, an electro-optic 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 modulates the probe light in time and space, the electro-optic crystal performs electro-optic sampling, and the imaging component measures the probe light spot. Furthermore, the imaging component includes: 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-optic crystal.

2. The terahertz spatiotemporal distribution single-shot measurement device according to claim 1, characterized in that, The probe optical modulation assembly includes a modulation pulse width device and a delay line.

3. The terahertz spatiotemporal distribution single-shot measurement device according to claim 2, characterized in that, The probe light modulation assembly also includes an aperture for spatially modulating the probe light.

4. The terahertz spatiotemporal distribution single-shot measurement device according to claim 2, characterized in that: The delay line consists of a precision electronically controlled translation stage and a roof reflector; The pulse width modulation device is selected from one or more of the following: dual-grating stretcher, dispersive glass, quad-grating stretcher, Offner stretcher, prism-pair stretcher, stretching fiber; and / or The modulation pulse width device broadens the short pulse width probe light.

5. The terahertz spatiotemporal distribution single-shot measurement device according to claim 4, characterized in that, The modulation pulse width device is selected from one or more of the following: dual grating stretcher, dispersive glass, prism stretcher.

6. The terahertz spatiotemporal distribution single-shot measurement device according to claim 5, characterized in that, The modulation pulse width device is a dual grating stretcher or a dispersive glass.

7. The terahertz spatiotemporal distribution single-shot measurement device according to claim 6, characterized in that, The pulse width modulation device is a dispersive glass.

8. The terahertz spatiotemporal distribution single-shot measurement device according to claim 3, characterized in that, The aperture is selected from one or more of the following: electric variable aperture, manual variable aperture, and square variable aperture.

9. The terahertz spatiotemporal distribution single-shot measurement device according to claim 8, characterized in that, The aperture is a square variable aperture.

10. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 9, characterized in that: The electro-optic 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; and / or The electro-optic sampling is achieved by generating a birefringence effect when terahertz light is incident on an electro-optic crystal, which modulates the polarization of the probe light.

11. The terahertz spatiotemporal distribution single-shot measurement device according to claim 10, characterized in that, The electro-optic crystal is selected from one or more of the following: zinc telluride crystal, gallium phosphide crystal, and gallium selenide crystal.

12. The terahertz spatiotemporal distribution single-shot measurement device according to claim 11, characterized in that, The electro-optic crystal is a zinc telluride crystal or a gallium phosphide crystal.

13. The terahertz spatiotemporal distribution single-shot measurement device according to claim 2, characterized in that, The delay line enables the probe light and terahertz to be spatiotemporally synchronized at the electro-optic crystal.

14. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 9, characterized in that, The imaging process involves 1:1 imaging or creating a reduced image of the probe light spot.

15. The terahertz spatiotemporal distribution single-shot measurement device according to claim 14, characterized in that, The imaging is a reduced image.

16. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 9, characterized in that: The number of lenses is 1 to 4; The quarter-wave plate is selected from one or more of the following: broadband achromatic waveplate, zero-order waveplate, multi-order waveplate; and / or The standard fixture is selected from one or more of the following: adjustable air gap standard fixture, fixed air gap standard fixture, and solid standard fixture.

17. The terahertz spatiotemporal distribution single-shot measurement device according to claim 16, characterized in that: The number of lenses is 2 to 3; The quarter-wave plate is a broadband achromatic waveplate or a zero-order waveplate; and / or The etalon is selected from one or more of the following: an adjustable air gap etalon, a fixed air gap etalon, or a fused silica solid etalon.

18. The terahertz spatiotemporal distribution single-shot measurement device according to claim 17, characterized in that: The number of lenses is 2; The quarter-wave plate is a broadband achromatic wave plate; and / or The etalon is an air gap adjustable etalon or a fused silica solid etalon.

19. The terahertz spatiotemporal distribution single-shot measurement device according to claim 18, characterized in that: The fused silica solid etalon is a solid etalon with 70-95% partial reflective coating on both sides and a thickness of 40-60 micrometers; and / or The adjustable air gap etalon is an adjustable air gap etalon with 80-90% partial reflective film on both sides, with an adjustable thickness of 30μm-100μm, and the substrate material is fused silica.

20. The terahertz spatiotemporal distribution single-shot measurement device according to claim 19, characterized in that: The fused silica solid etalon is a solid etalon with 80-90% partial reflective coating on both sides and a thickness of 45-55 micrometers; and / or The adjustable air gap etalon is an adjustable air gap etalon with 85% partial reflective film coated on both sides, with an adjustable thickness of 30μm~100μm, and the substrate material is fused silica.

21. The terahertz spatiotemporal distribution single-shot measurement device according to claim 20, characterized in that, The fused silica solid etalon is a solid etalon with 85% partial reflective coating on both sides and a thickness of 50 micrometers.

22. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 9, characterized in that, The transmission grating is located behind the etalon, which spatially separates the diffracted light components of different wavelengths.

23. The terahertz spatiotemporal distribution single-shot measurement device according to claim 22, characterized in that, The grating has 100~500 lines / mm.

24. The terahertz spatiotemporal distribution single-shot measurement device according to claim 23, characterized in that, The grating has 150~400 lines / mm.

25. The terahertz spatiotemporal distribution single-shot measurement device according to claim 24, characterized in that, The grating has 300 lines per mm.

26. The terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 9, characterized in that, The imaging assembly also includes a prism and a camera, with the prism located in front of the camera.

27. The terahertz spatiotemporal distribution single-shot measurement device according to claim 26, characterized in that: The prism splits light into different polarizations; and / or The camera is a visible light band or near-infrared band camera.

28. The terahertz spatiotemporal distribution single-shot measurement device according to claim 27, characterized in that: The prism is selected from one of the following: Wollaston prism, Roshon prism, Glan Taylor prism, laser Glan prism; and / or The camera is an area scan camera.

29. The terahertz spatiotemporal distribution single-shot measurement device according to claim 28, characterized in that, The prism is either a Wollaston prism or a Roxon prism.

30. The terahertz spatiotemporal distribution single-shot measurement device according to claim 29, characterized in that, The prism in question is a Wollaston prism.

31. A single-shot measurement method, characterized in that, The single-shot measurement method uses the terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 30 to perform single-shot measurement.

32. The single-shot measurement method according to claim 31, characterized in that, The single-shot measurement method includes the following steps: (1) After the probe beam is modulated by the probe beam modulation component, it is incident on the electro-optic crystal in time and space synchronous with the terahertz beam and is imaged by the imaging component. (2) By comparing the changes in the light spot with the same wavelength and polarization when there is no terahertz, the spatial distribution of the terahertz light spot can be obtained; by comparing the changes in the light spot with the same polarization and position at different wavelengths, the time domain information of terahertz can be obtained.

33. A terahertz spatiotemporal distribution measurement system, characterized in that, The terahertz spatiotemporal distribution measurement system includes a terahertz spatiotemporal distribution single-shot measurement device according to any one of claims 1 to 30.

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