Three-dimensional quantum imaging system based on array entangled light source

Abstract

The invention discloses a three-dimensional quantum imaging system based on an array entangled light source, and the system comprises the following modules: an array entangled light source module which is composed of a pump laser, a pump light splitting optical path structure, and a Bragg reflection waveguide array light source chip of an aluminum gallium arsenic array waveguide structure, and is used as a light source to generate entangled photon pairs; the array light beam splitting module is used for separating entangled photon pairs generated by different waveguides in the array; the spatial dispersion imaging module is used for separating signal light photons; the time dispersion module is used for separating idler frequency light photons; the polarization analysis module is used for improving the imaging signal-to-noise ratio; and the coincidence measurement module is used for carrying out coincidence measurement on the obtained signal to obtain imaging data. According to the invention, rapid, high-signal-to-noise-ratio and anti-interference three-dimensional quantum imaging is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of quantum imaging, and in particular relates to a three-dimensional quantum imaging system based on an array entangled light source. Background Art

[0002] Quantum imaging is a technology that uses quantum mechanical properties such as entanglement and superposition for imaging, and it has attracted widespread attention worldwide. Traditional imaging technology relies on the intensity distribution of the detection light, while quantum imaging can obtain clear images in low-light conditions or high-noise environments through phenomena such as quantum entanglement, while having higher accuracy and resolution. For example, the "ghost imaging" technology based on entangled photons can obtain image information through indirect detection. In addition, quantum imaging shows significant advantages in super-resolution imaging, low-photon imaging, and anti-interference imaging, and has broad application potential, especially in the fields of biological imaging, remote sensing, and security detection. Although quantum imaging is still in the experimental research and technical verification stage, its huge application prospects are driving researchers to continuously explore new quantum imaging mechanisms and efficient detection methods.

[0003] Although there are a series of classical light quantum imaging and computational imaging works derived from quantum "ghost imaging" schemes, they have the following weaknesses: 1. Compared with the entangled photon pairs of quantum light sources, the correlation of classical light is not perfect, which will hinder the improvement of signal-to-noise ratio; 2. Compared with quantum light sources, classical light cannot break through the diffraction limit, which limits its high-precision imaging capabilities; 3. Classical light sources are still based on complete spatial optical paths and blocks, which is difficult to achieve integration. Therefore, quantum imaging based on quantum light sources still has unique uses and is irreplaceable.

[0004] Most current quantum imaging solutions use a point-by-point scanning method, which requires a mechanical structure to achieve two-dimensional imaging of macroscopic objects. It is difficult to strike a balance between imaging clarity and imaging speed. The reason is that the channel capacity that a single light source can provide is limited. Therefore, efficient quantum imaging has high requirements for light source brightness, quantity, and multiplexing. Summary of the invention

[0005] The present invention aims to provide a three-dimensional quantum imaging system based on an array entangled light source to achieve fast, high signal-to-noise ratio, and anti-interference three-dimensional quantum imaging.

[0006] In order to achieve the purpose of the present invention, the present invention provides a three-dimensional quantum imaging system based on an array entangled light source, characterized in that it includes the following modules:

[0007] The array entangled light source module is composed of a pump laser, a pump splitter optical path structure, and a Bragg reflection waveguide array light source chip of an aluminum gallium arsenide array waveguide structure, and is used as a light source to generate entangled photon pairs; the pump splitter optical path structure is composed of a cascade of one-to-two optical fiber beam splitters, and the number of cascade layers is determined by the number of waveguides contained in the array entangled light source module, and the pump laser outlet of the last stage is a lens optical fiber;

[0008] An array light splitting module is used to separate entangled photon pairs generated by different waveguides in the array; the array light splitting module is composed of a long-wave pass filter, an aspheric lens, a spherical lens, a right-angle prism, and a silver-coated reflector, and is fixed on the same platform;

[0009] A spatial dispersion imaging module, used for separating signal light photons; the spatial dispersion imaging module comprises a reflector, a dispersion grating, a focusing lens, a collecting lens, a color filter, a polarization beam splitter prism, and a one-dimensional displacement stage;

[0010] A time dispersion module for separating idler photons;

[0011] A polarization analysis module is used to improve the imaging signal-to-noise ratio; the polarization analysis module comprises two identical parts, which are respectively located between the coincidence measurement module and the time dispersion module, and between the coincidence measurement module and the space dispersion module, and each of which comprises a quarter wave plate, a half wave plate, and a polarization beam splitter prism, and is used to adjust and test polarization;

[0012] A coincidence measurement module is used to perform coincidence measurement on the obtained signal to obtain imaging data; the coincidence measurement module is composed of two single-photon detectors, a cage structure, and a time tag module; the single-photon detector includes a photomultiplier tube, an avalanche photodetector or a superconducting single-photon detector, which is used to detect single-photon information and convert it into an electrical signal; the time tag module is based on a time tag module of a field programmable logic gate array or a time tag module of an application-specific integrated circuit, which is used to perform coincidence measurement on the electrical signal detected by the single-photon detector.

[0013] Furthermore, the Bragg reflection waveguide array light source chip is composed of a 230nm thick Al0.17Ga0.83As core layer sandwiched by a six-period Bragg structure consisting of alternating 127nm thick Al0.28Ga0.72As layers and 622nm thick Al0.72Ga0.28As layers, with a width of 5.1μm, an etching depth of 4.15μm, and a length of 4mm.

[0014] Furthermore, the long-wave pass filter is used to separate signal light and idler light, with an operating wavelength of 1550nm, transmitting signal light and reflecting idler light; the aspheric lens has a focal length of f=2.8mm, and is used to separate and preliminarily collimate photon pairs at different positions with an array end face distance of 127μm; the spherical lens has a focal length of f=50mm, and is used to further collimate and adjust the parallelism of the separated light sources at different positions; the silver-coated reflector has a wavelength coating of 1550nm, and is used to adjust the incident angle; the right-angle prism is used to adjust the optical path and optical length, so that the three-way light is separated, and the incident angle is adjusted to facilitate beam combining; the spherical lens has a focal length of f=50mm, and is used to preliminarily combine the converging three-way light.

[0015] Furthermore, the dispersion grating has a blazing wavelength of 1600nm, a blazing angle of 28 degrees, and a line density of 600 per nanometer, and is used to spatially disperse light; the reflector is a silver-plated reflector with a coating wavelength of 1550nm, and is used to adjust the incident angle; the focusing lens is a spherical lens with a focal length of f=5cm, and is used to focus and spatially disperse; the collecting lens is a spherical lens with a focal length of f=5cm, and is used to collect imaging light signals; the color filter and the polarization beam splitter are used for polarization screening and identification; the one-dimensional displacement stage has a displacement accuracy of 1μm and a displacement range of ±2.5cm.

[0016] Furthermore, the time dispersion module includes a dispersion optical fiber with a length of 5 km, a 1550 nm single mode, a core diameter of 9 μm, a coating of 125 μm, and a dispersion capability of 16.5 picoseconds per nano-kilometer; a cage structure is an adjustable combination device composed of an aspheric lens and an optical fiber coupling disk integrated on a cage frame, which is used to efficiently collect photons propagating in space.

[0017] Compared with the prior art, the significant progress of the present invention is as follows: (1) The present invention is based on the polarization entangled light source of the AlGaAs array, which has the characteristics of high brightness and high code rate, and multiple waveguides are used in parallel for imaging, combined with the high bandwidth and high brightness of each waveguide, it has the advantages of fast imaging rate and high signal-to-noise ratio; (2) The present invention combines multiple array light sources with frequency multiplexing, and can form a two-dimensional image in a single time without mechanical scanning, and can form a three-dimensional image in combination with mechanical scanning; (3) The polarization entanglement analysis module in the present invention can effectively resist interference and improve imaging quality.

[0018] In order to more clearly illustrate the functional characteristics and structural parameters of the present invention, further description is given below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 It is an overall schematic diagram of the present invention;

[0021] Figure 2 is a schematic diagram of the light source portion of the present invention;

[0022] Figure 3 It is a schematic diagram of the light splitting part of the present invention;

[0023] Figure 4 Schematic diagram of the spatial dispersion module of the present invention. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] The present invention is a three-dimensional quantum imaging system based on an array entangled light source, combined with Figure 1 , including the following modules:

[0026] The array entangled light source module is composed of a pump laser, a pump splitting optical path structure, and a Bragg reflection waveguide array light source chip of an aluminum gallium arsenide array waveguide structure, and is used as a light source to generate entangled photon pairs;

[0027] The pump splitting optical path structure, combined with Figure 2 , as shown, it is composed of a cascade of one-to-two optical fiber beam splitters, the number of cascade layers is determined by the number of waveguides contained in the array entangled light source module, and the pump laser outlet of the last stage is a lens optical fiber;

[0028] The Bragg reflection waveguide array light source chip is composed of a 230nm thick A10.17Ga0.83As core layer sandwiched by a six-period Bragg structure consisting of alternating 127nm thick Al0.28Ga0.72As layers and 622nm thick Al0.72Ga0.28As layers, with a width of 5.1μm, an etching depth of 4.15μm and a length of 4mm.

[0029] An array optical beam splitting module is used to separate entangled photon pairs generated by different waveguides in the array;

[0030] The array light splitting module is composed of an aspherical lens, a spherical lens, a long-wave filter, a right-angle prism, and a silver-plated reflector, and is fixed on the same platform. Figure 3 The light beam passes through a long-pass filter (not shown in the figure) and is initially collimated by an aspheric lens. It then passes through a spherical lens to separate the photons generated by different waveguides. The signal light generated by each waveguide passes through the long-pass filter, while the idle light is reflected. The signal light generated by different waveguides is adjusted by a silver-coated mirror and a right-angle prism to adjust the optical path. It is then reconverged and collected and collimated by a spherical lens and an aspheric lens.

[0031] The array light splitting module is a light splitting system composed of multiple lenses and multiple reflectors.

[0032] The long-wave pass filter is used to separate signal light and idler light, has an operating wavelength of 1550nm, transmits signal light, and reflects idler light;

[0033] The focal length of the aspheric lens is f=2.8 mm, and is used to separate and preliminarily collimate photon pairs at different positions with an array end face distance of 127 μm;

[0034] The focal length of the spherical lens is f=50mm, which is used to further collimate and adjust the parallelism of the separated light sources at different positions; the wavelength coating of the silver-coated reflector is 1550nm, which is used to adjust the incident angle;

[0035] The right-angle prism is used to adjust the optical path and optical length so that the three-way light can be separated, and the incident angle can be adjusted to facilitate beam combination;

[0036] The spherical lens has a focal length of f=50 mm and is used for preliminarily combining the three converging light beams.

[0037] Spatial dispersion imaging module, used to separate signal light photons;

[0038] The spatial dispersion imaging module includes a reflector, a dispersion grating, a focusing lens, a collecting lens, a color filter, a polarization beam splitter prism, and a one-dimensional displacement stage along the optical axis; Figure 4 The generated broadband signal light is adjusted in angle by a reflector and reflected on a dispersion grating. Photons of different frequencies are focused at different positions by a focusing lens and reflected on the object to be imaged. The reflected photons are re-collimated by a collecting lens and enter the polarization analysis module and coincidence measurement module.

[0039] The dispersion grating has a blazing wavelength of 1600nm, a blazing angle of 28 degrees, and a line density of 600 per nanometer, and is used to spatially disperse light;

[0040] The reflector is a silver-plated reflector with a wavelength coating of 1550nm, which is used to adjust the incident angle;

[0041] The focusing lens is a spherical lens with a focal length of f=5 cm, which is used for focusing and spatial dispersion;

[0042] The collecting lens is a spherical lens with a focal length of f=5 cm, which is used for collecting imaging light signals;

[0043] The color filter and the polarization beam splitter are used for polarization screening and identification;

[0044] The one-dimensional translation stage has a displacement accuracy of 1 μm and a displacement range of ±2.5 cm.

[0045] A time dispersion module for separating idler photons;

[0046] The time dispersion module comprises a dispersion optical fiber with a length of 5 km, a 1550 nm single mode, a core diameter of 9 μm, a coating of 125 μm, and a dispersion capability of 16.5 picoseconds per nano-kilometer; a cage structure is a combined adjustable device composed of an aspheric lens and an optical fiber coupling disk integrated on a cage frame, which is used to efficiently collect photons propagating in space.

[0047] A polarization analysis module is used to improve the imaging signal-to-noise ratio; the polarization analysis module contains two identical parts, which are respectively located between the coincidence measurement module and the time dispersion module, and between the coincidence measurement module and the space dispersion module, and each includes a quarter wave plate, a half wave plate, and a polarization splitter prism for adjusting and testing polarization.

[0048] The coincidence measurement module is used to perform coincidence measurement on the obtained signal to obtain imaging data.

[0049] The coincidence measurement module includes two single photon detectors, a cage structure, and a time tag module;

[0050] The single-photon detector includes a photomultiplier tube, an avalanche photodetector or a superconducting single-photon detector, which is used to detect single-photon information and convert it into an electrical signal;

[0051] The time tag module is based on a time tag module of a field programmable logic gate array or a time tag module of a dedicated integrated circuit, and is used to perform coincidence measurement on the electrical signal detected by the single photon detector.

[0052] The principle of this program:

[0053] The array entangled light source module is composed of three single aluminum gallium arsenide Bragg reflection waveguides with similar performance. For each waveguide, 1% of the power of a single-mode fiber-coupled continuous wave laser with a central wavelength of 780nm is distributed to a spectrum analyzer for wavelength calibration, and is divided into four paths using a one-to-four fiber beam splitter, three of which are injected into three waveguides. For each waveguide, a fiber polarization controller is used to adjust the polarization of the pump light before injecting it into the aluminum gallium arsenide / gallium arsenide waveguide, and broadband polarization entangled photon pairs are generated through the combined second-type spontaneous parametric down conversion; the laser pumps the entangled photon pair source waveguide to generate entangled photon pairs of frequency and polarization degrees of freedom, and the quantum state is expressed as:

[0054]

[0055] Where N is the total number of frequency pairs generated, |H> / |V> represents the horizontal or vertical polarization state, and |ω s > / |ω i > represents the frequency state of the signal or idler photon and satisfies the energy conservation condition, and n is the label of each frequency.

[0056] This design fully utilizes the advantages of aluminum gallium arsenide / gallium arsenide semiconductor materials, which are very suitable for devices such as lasers and modulators and provide high second-order nonlinearity. A Bragg reflection waveguide structure is used to achieve mode phase matching through bounded total reflection mode and quasi-bounded Bragg reflection waveguide mode, where the bounded total reflection mode is usually formed between the high and low refractive index interlayers, while the Bragg reflection waveguide mode is guided by lateral Bragg reflection between the core and the periodic interlayer. The pump light is divided into four beams of equal power by cascaded beam splitters, of which three beams are coupled into the waveguide. In this example, a simple example is three beams. In actual applications, more beam splitters can be cascaded to couple into 2 N In each waveguide, N is the number of cascaded layers, and polarization-entangled photon pairs are generated through the spontaneous parametric down-conversion process.

[0057] Array light beam splitting module: After the entangled photon pair consisting of signal photons and idler photons is coupled out from the other end of the array light source, the light beam is collimated by the aspherical lens. At this time, the spacing between the multiple coupled light beams is about 127μm. The three coupled light beams are separated by the spherical lens. The coupled light passes through the long-pass filter to separate the generated entangled photon pairs into signal photons and idler photons. The idler photons are reflected and collected to enter the time dispersion light path. The signal photons pass through the long-pass filter and pass through the two groups of silver-coated reflectors and the right-angle prism group to separate the three light beams and adjust the optical path. The three light beams are then merged by the spherical lens and enter the spatial dispersion imaging module for imaging.

[0058] The spatial dispersion module: adjusts the angle of light emission of the signal photons coupled out of the array optical beam splitting module through a reflector so that it is incident on the dispersion grating at a specific angle. Light of different wavelengths is incident on the lens at different angles, and then focused on different lateral positions on the imaging surface, and reflected to the collection lens at different angles. After passing through the polarization analysis module, it is uniformly collected in the coincidence measurement module.

[0059] The time dispersion module: the idle photons coupled out of the array optical beam splitting module are propagated through the dispersive optical fiber to the single photon detector in the coincidence measurement module of the front polarization analysis module. Since light of different wavelengths has different group velocities in the optical fiber, when the time difference between idle photons of different wavelengths reaching the detector is large enough, the detector can distinguish light of different wavelengths. The idle photons arriving at different times correspond to signal photons reflected at different positions in the spatial dispersion module. Finally, the coincidence count-time intensity distribution detected by the detector corresponds to the one-dimensional image at the other end.

[0060] The polarization analysis module is used to improve the imaging quality and signal-to-noise ratio. Since the signal light and the idler light are polarization entangled, the signal light reflected by the object is filtered using a quarter-wave plate, a half-wave plate and a polarization beam splitter prism, which can accurately extract the imaging information, reduce the interference of stray light and improve the signal-to-noise ratio.

[0061] The imaging method implemented in this scheme is as follows:

[0062] The method for realizing two-dimensional imaging is to arrange the waveguides of the array light source perpendicular to the arrangement direction of the dispersion grating lines in the optical path of the entangled light source splitter module. In this example, it is a two-dimensional imaging of 3*N pixels, which can actually be L*N, where L is the number of waveguides in the array light source. Each waveguide can provide one-dimensional imaging of N pixels. The size of N is determined by the spot size, the line density of the dispersion grating, and the incident angle. There are three waveguides in total, combined with Figure 1 , the direction of the waveguide is perpendicular to the direction of one-dimensional imaging.

[0063] A method for realizing three-dimensional imaging is to move the focusing lens in the spatial dispersion imaging part along the optical axis direction of the lens so that the focal plane of the lens falls on different positions. The focal plane falls on M different positions, which can be 3*M*N, or actually L*M*N, where L is the number of waveguides in the array light source, and the three directions are perpendicular to each other.

[0064] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0065] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A three-dimensional quantum imaging system based on an array entangled light source, characterized in that: Includes the following modules: The array entangled light source module is composed of a pump laser, a pump splitting optical path structure, and a Bragg reflection waveguide array light source chip of an aluminum gallium arsenide array waveguide structure, and is used as a light source to generate entangled photon pairs; The pump splitting optical path structure is composed of a cascade of one-to-two optical fiber beam splitters, the number of cascade layers is determined by the number of waveguides contained in the array entangled light source module, and the pump laser outlet of the last stage is a lens optical fiber; An array optical beam splitting module is used to separate entangled photon pairs generated by different waveguides in the array; Spatial dispersion imaging module, used to separate signal light photons; A time dispersion module for separating idler photons; Polarization analysis module, used to improve the imaging signal-to-noise ratio; The coincidence measurement module is used to perform coincidence measurement on the obtained signal to obtain imaging data.

2. A three-dimensional quantum imaging system based on an array entangled light source according to claim 1, characterized in that: The Bragg reflection waveguide array light source chip is composed of a 230nm thick A10.17Ga0.83As core layer sandwiched by a six-period Bragg structure consisting of alternating 127nm thick A10.28Ga0.72As layers and 622nm thick A10.72Ga0.28As layers, with a width of 5.1μm, an etching depth of 4.15μm, and a length of 4mm.

3. A three-dimensional quantum imaging system based on an array entangled light source according to claim 1, characterized in that: The array optical beam splitting module is composed of a long-wave filter, an aspheric lens, a spherical lens, a right-angle prism, and a silver-coated reflector, and is used for separation, collimation, and optical path and optical length control of signal photons and idler photons in entangled photon pairs and is fixed on the same platform; After the entangled photon pairs consisting of signal photons and idler photons are coupled out from the other end of the array light source, the light beams are collimated by the aspherical lens. At this time, the spacing between the multiple coupled light beams is about 127μm. The three coupled light beams are separated by a spherical lens. The coupled light passes through the long-pass filter to separate the generated entangled photon pairs into signal photons and idler photons. The idler photons are reflected and collected to enter the time dispersion light path. The signal photons pass through the long-pass filter and pass through the two groups of silver-coated mirrors and the right-angle prism group to separate the three light beams and adjust the optical path. The three light beams are then merged by the spherical lens and enter the spatial dispersion imaging module for imaging.

4. A three-dimensional quantum imaging system based on an array entangled light source according to claim 3, characterized in that: The long-wave pass filter is used to separate signal light and idler light, has an operating wavelength of 1550nm, transmits signal light, and reflects idler light; The focal length of the aspheric lens is f=2.8 mm, and is used to separate and preliminarily collimate photon pairs at different positions with an array end face distance of 127 μm; The focal length of the spherical lens is f=50mm, which is used to further collimate and adjust the parallelism of the separated light sources at different positions; the wavelength coating of the silver-coated reflector is 1550nm, which is used to adjust the incident angle; The right-angle prism is used to adjust the optical path and optical length so that the three-way light can be separated, and the incident angle can be adjusted to facilitate beam combination; The spherical lens has a focal length of f=50 mm and is used for preliminarily combining the three converging light beams.

5. The three-dimensional quantum imaging system based on array entangled light source according to claim 1, characterized in that: The spatial dispersion imaging module includes a reflector, a dispersion grating, a focusing lens, a collecting lens, and a one-dimensional translation stage; The signal photons coupled out of the array optical beam splitting module are incident on the dispersion grating by adjusting the light emission angle through the reflector. Light of different wavelengths is incident on the focusing lens at different angles, focused on different lateral positions on the imaging surface, and reflected to the collection lens at different angles. Finally, they are uniformly collected by the polarization analysis module and coincide with the measurement module.

6. A three-dimensional quantum imaging system based on an array entangled light source according to claim 5, characterized in that: The dispersion grating has a blazing wavelength of 1600nm, a blazing angle of 28 degrees, and a line density of 600 per nanometer, and is used to spatially disperse light; The reflector is a silver-plated reflector with a wavelength coating of 1550nm, which is used to adjust the incident angle; The focusing lens is a spherical lens with a focal length of f=5 cm, which is used for focusing and spatial dispersion; The collecting lens is a spherical lens with a focal length of f=5 cm, which is used for collecting imaging light signals; The color filter and the polarization beam splitter are used for polarization screening and identification; The one-dimensional translation stage has a displacement accuracy of 1 μm and a displacement range of ±2.5 cm.

7. The three-dimensional quantum imaging system based on array entangled light source according to claim 1, characterized in that: The time dispersion module includes a dispersion optical fiber with a length of 5 km, a 1550 nm single mode, a core diameter of 9 μm, a coating of 125 μm, and a dispersion capability of 16.5 picoseconds per nano-kilometer; a cage structure composed of an aspheric lens and an optical fiber coupling disk integrated on a cage frame, which is an adjustable device for efficiently collecting photons propagating in space; The idle photons coupled out of the array optical beam splitting module are propagated through the dispersive optical fiber to the single-photon detector in the coincidence measurement module of the front polarization analysis module. When the time difference of idle photons of different wavelengths arriving at the detector is large enough, the detector distinguishes light of different wavelengths. The idle photons arriving at different times correspond to signal photons reflected at different positions in the spatial dispersion module. Finally, the coincidence count-time intensity distribution detected by the detector corresponds to the one-dimensional image at the other end.

8. The three-dimensional quantum imaging system based on array entangled light source according to claim 1, characterized in that: The polarization analysis module contains two identical parts, which are respectively located between the coincidence measurement module and the time dispersion module, and between the coincidence measurement module and the space dispersion module, and each includes a quarter wave plate, a half wave plate, and a polarization splitter prism for adjusting and testing polarization.

9. The three-dimensional quantum imaging system based on array entangled light source according to claim 1, characterized in that: The coincidence measurement module includes two single photon detectors, a cage structure, and a time tag module; The single-photon detector includes a photomultiplier tube, an avalanche photodetector or a superconducting single-photon detector, which is used to detect single-photon information and convert it into an electrical signal; The time tag module is based on a time tag module of a field programmable logic gate array or a time tag module of a dedicated integrated circuit, and is used to perform coincidence measurement on the electrical signal detected by the single photon detector.

10. The three-dimensional quantum imaging system based on array entangled light source according to claim 2, characterized in that: The array entangled light source module is composed of three single aluminum gallium arsenide Bragg reflection waveguides with similar performance. For each waveguide, 1% of the power of a single-mode fiber-coupled continuous wave laser with a central wavelength of 780nm is distributed to a spectrum analyzer for wavelength calibration, and is divided into four paths using a one-to-four fiber beam splitter, three of which are injected into three waveguides. For each waveguide, a fiber polarization controller is used to adjust the polarization of the pump light before injecting it into the aluminum gallium arsenide / gallium arsenide waveguide, and broadband polarization entangled photon pairs are generated through the combined second-type spontaneous parametric down conversion; the laser pumps the entangled photon pair source waveguide to generate entangled photon pairs of frequency and polarization degrees of freedom, and the quantum state is expressed as: Where N is the total number of frequency pairs generated, |H> / |V> represents the horizontal or vertical polarization state, and |ω s > / |ω i > represents the frequency state of the signal or idler photon and satisfies the energy conservation condition, and n is the label of each frequency.

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