A high dynamic photon counting single-pixel imaging device and method

Abstract

The application discloses a high dynamic photon counting single-pixel imaging device and method, and relates to the field of single-pixel imaging. A laser emission component is used to emit pulsed laser to a target object to be imaged. The target object to be imaged reflects light containing target object information. A beam splitting component is used to split the light containing target object information into transmitted light and reflected light. A first imaging component is used to detect and count the reflected light and generate a first pulse signal. A second imaging component is used to modulate, detect and count the transmitted light and generate a second pulse signal. A time-dependent single-photon counting imaging component is used to accumulate the first pulse signal and the second pulse signal to obtain corresponding calibration signals and image signals. The image signals are calibrated using the calibration signals, and then target object image reconstruction is performed based on the calibrated image signals and modulation information. The application can reduce the requirement for light source stability and greatly enhance the imaging capability in unstable and complex scenes.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of single-pixel imaging, in particular to a high dynamic photon counting single-pixel imaging device and method. BACKGROUND

[0002] Single-pixel imaging technology, as a branch of computational imaging, modulates the light field containing object information in several times, uses a single-pixel detector without spatial resolution to obtain the intensity information of the modulated object, and performs correlation operation on the obtained intensity information to realize image reconstruction. In each measurement, the single-pixel imaging system collects the light intensity of about half of the object, so it has higher sensitivity.

[0003] In recent years, in order to further explore the limit of the detection sensitivity of single-pixel imaging technology, single-pixel combined with high-sensitivity photon imaging technology has become a research hotspot. However, in the traditional single-photon counting single-pixel imaging technology, the spatial light field containing object information is encoded and modulated, and a single-photon detector is used to receive the light intensity information corresponding to the modulation code. The correlation operation between the detection signal and the code matrix is performed to realize the reconstruction of the image. Since the DMD is an intensity modulation, if the stability of the light source is poor, it will affect the light intensity signal corresponding to the modulation code, and it is difficult to realize high-quality imaging. In the prior art, when obtaining target information using a single-path photon counting single-pixel imaging structure, a large amount of energy in the collection light path is wasted, and it is difficult to cope with complex environments with unstable light sources. SUMMARY

[0004] The purpose of the present application is to provide a high dynamic photon counting single-pixel imaging device and method, which can reduce the requirement for light source stability and greatly enhance the imaging capability in complex scenes with unstable light sources.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] In a first aspect, the present application provides a high dynamic photon counting single-pixel imaging device, comprising a laser emission assembly, a beam splitting assembly, a first imaging assembly, a second imaging assembly and a time-correlated single-photon counting imaging assembly;

[0007] The laser emission assembly is used to emit pulsed laser to a target object to be imaged; the target object to be imaged reflects light containing target object information to the beam splitting assembly;

[0008] The beam splitting assembly is used to divide the received light containing target object information into transmitted light and reflected light, and send the reflected light to the first imaging assembly and the transmitted light to the second imaging assembly;

[0009] The first imaging component is configured to detect and count the received reflected light and send a generated first pulse signal to the time-correlated single photon counting imaging component; and the second imaging component is configured to modulate, detect and count the received transmitted light and send modulation information and a generated second pulse signal to the time-correlated single photon counting imaging component.

[0010] The time-correlated single photon counting imaging component is configured to accumulate the first pulse signal and the second pulse signal to obtain a corresponding calibration signal and an image signal, calibrate the image signal by using the calibration signal, and then reconstruct a target object image based on the calibrated image signal and the modulation information.

[0011] In a second aspect, the application provides a high dynamic photon counting single-pixel imaging method, comprising:

[0012] The laser emission component emits pulsed laser to a target object to be imaged; the target object to be imaged reflects light containing target object information to a beam splitting component; wherein the laser emission component randomly adjusts laser power to a preset power range during imaging to simulate a dynamic light source.

[0013] The beam splitting component splits the received light containing target object information into transmitted light and reflected light, and sends the reflected light to the first imaging component and the transmitted light to the second imaging component.

[0014] The first imaging component detects and counts the received reflected light and generates a first pulse signal; and the second imaging component modulates, detects and counts the received transmitted light and generates a second pulse signal.

[0015] The time-correlated single photon counting imaging component accumulates the first pulse signal and the second pulse signal to obtain a corresponding calibration signal and an image signal.

[0016] The time-correlated single photon counting imaging component calibrates the image signal by using the calibration signal, and then reconstructs a target object image based on the calibrated image signal and the modulation information.

[0017] According to the specific embodiments provided in the application, the application has the following technical effects: the application provides a high dynamic photon counting single-pixel imaging device and method, wherein a beam splitting component is arranged to split light containing target object information into transmitted light and reflected light, and the reflected light is sent to a first imaging component to obtain a corresponding first pulse signal for calibration, and the transmitted light is sent to a second imaging component to obtain a corresponding second pulse signal for imaging, then the image signal corresponding to the second pulse signal is calibrated by the calibration signal corresponding to the first pulse signal, and then the target object image reconstruction is realized, and an accurate target object image is obtained. In this process, the beam splitting and calibration processes are performed to realize the reuse of energy in the optical path, reduce the stability requirement of the light source, and even in the scene with poor light source stability, high-quality imaging can be obtained through calibration, and the imaging capability in the complex scene with unstable light source is greatly enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The structural schematic diagram of the high dynamic photon counting single-pixel imaging device provided by an embodiment of the application.

[0020] Figure 2 The schematic diagram of the uncalibrated modulation intensity and imaging result provided by an embodiment of the application.

[0021] Figure 3 The schematic diagram of the calibration data provided by an embodiment of the application.

[0022] Figure 4 The schematic diagram of the calibrated modulation intensity and imaging result provided by an embodiment of the application.

[0023] Reference signs: 1-laser, 2-target object to be imaged, 3-semi-transparent semi-reflective beam splitter, 4-first converging lens, 5-first single-photon detector, 6-optical imaging component, 7-space light modulator, 8-optical converging coupling component, 9-second single-photon detector, 10-time-correlated single-photon counter, 11-imaging component. DETAILED DESCRIPTION

[0024] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0025] The present application designs high dynamic photon counting single pixel imaging based on light source calibration, reduces the requirement for light source stability while improving the system signal utilization rate without reducing the imaging quality, greatly enhances the imaging capability in complex scenes with unstable light sources, and realizes good signal-to-noise ratio, high detection sensitivity, and effective information acquisition image in complex weather.

[0026] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0027] In one exemplary embodiment, as shown in Figure 1 a high dynamic photon counting single pixel imaging device is provided, which includes a laser emission component, a beam splitting component, a first imaging component, a second imaging component and a time-dependent single photon counting imaging component.

[0028] The laser emission component includes a laser 1, which can be a pulsed laser. The operating wavelength range of the laser 1 is 400 nm-2700 nm. The repetition frequency of the laser 1 is 40 MHz. The average power range of the laser 1 is 0 W-4 W. The beam splitting component includes a semi-transparent half-mirror 3. The first imaging component includes a first converging lens 4 and a first single photon detector 5 arranged in sequence. The second imaging component includes an optical imaging component 6, a spatial light modulator 7, an optical converging coupling component 8 and a second single photon detector 9. The optical converging coupling component includes a quartz flat-convex lens and a fiber coupler. The time-dependent single photon counting imaging component includes a time-dependent single photon counter TCSPC 10 and an imaging component 11 arranged in sequence.

[0029] In one specific application example, the imaging component 11 can be a computer, and the spatial light modulator 7 can be a digital micromirror array DMD.

[0030] In another specific application example, the laser emission component is used to emit pulsed laser to the target object 2 to be imaged, i.e. the laser 1 projects active pulsed light onto the target object 2 to be imaged, and then the target object 2 to be imaged reflects light containing target object information to the beam splitting component.

[0031] The beam splitting component is used to split the received light containing target information into transmitted light and reflected light, and send the reflected light to the first imaging component and the transmitted light to the second imaging component; specifically, the semi-transparent semi-reflective beam splitter 3 is used to split the light containing target information into transmitted light and reflected light.

[0032] The first imaging component is used to detect and count the received reflected light, and send the generated first pulse signal to the time-correlated single photon counting imaging component, and the first pulse signal generated by the first imaging component can be regarded as a calibration pulse signal. Specifically, the first converging lens 4 is used to converge the received reflected light to the first single photon detector 5; the first single photon detector 5 is used to detect the light signal converged via the first converging lens 4 and convert it into a first pulse signal, and then send the first pulse signal to the time-correlated single photon counting imaging component.

[0033] The second imaging component is used to modulate, detect and count the received transmitted light, and send the modulation information and the generated second pulse signal to the time-correlated single photon counting imaging component; specifically, the optical imaging component 6 is used to image the received transmitted light to the spatial light modulator 7, that is, the light beam transmitted by the semi-transparent semi-reflective beam splitter 3 is imaged onto the digital micromirror array DMD micromirror surface through the optical imaging component 6.

[0034] The spatial light modulator 7 is used to modulate the received imaged light and send the modulation information to the time-correlated single photon counting imaging component; the modulated light is reflected to the light converging coupling component 8 and coupled and collected to the second single photon detector 9 by the light converging coupling component 8; the second single photon detector 9 is used to detect the light signal echoed via the light converging coupling component 8 and convert it into a second pulse signal, and then send the second pulse signal to the time-correlated single photon counting imaging component.

[0035] In another specific application example, the Hadamard matrix is used as the modulation code in the spatial light modulator.

[0036] The time-correlated single photon counting imaging component is used to accumulate the first pulse signal and the second pulse signal to obtain corresponding calibration signals and image signals, calibrate the image signals based on the calibration signals, and then reconstruct the target image based on the calibrated image signals and the modulation information.

[0037] Specifically, the time-correlated single photon counter 10 is connected with the spatial light modulator 7, and the time-correlated single photon counter 10 is configured to: acquire modulation information of the spatial light modulator 7; and accumulate the first pulse signal and the second pulse signal to obtain an analog value of a corresponding calibration signal and an analog value of an image signal. That is, the time-correlated single photon counter 10 accumulates the pulse signals detected by the two single photon detectors SPADs, and gives the analog value of the corresponding calibration signal and the analog value of the image signal.

[0038] The imaging component 11 is connected with the time-correlated single photon counter 10, and the imaging component 11 is configured to: divide the analog value of the image signal by the analog value of the calibration signal, thereby realizing the process of calibrating the image signal by the calibration signal, and obtaining a calibrated image signal; and reconstruct an image of the target object according to the calibrated image signal and the modulation information of the spatial light modulator 7.

[0039] Based on the same inventive concept, the embodiment of the present application also provides a high dynamic photon counting single-pixel imaging method. The implementation scheme for solving the problem provided by the method is similar to the implementation scheme described in the above device, so the specific limitations in one or more method embodiments provided below can refer to the limitations of the device in the above, which will not be described here. The high dynamic photon counting single-pixel imaging method of the present application includes the following steps 100-500.

[0040] Step 100: emitting pulse laser to a target object to be imaged by a laser emitting assembly; the target object to be imaged reflects light containing target object information to a beam splitting assembly; wherein the laser emitting assembly randomly adjusts the laser power to a preset power range during the imaging process to simulate a dynamic light source.

[0041] In one specific application example, the laser emitting assembly emits laser to the target object to be imaged and randomly adjusts the laser power to about 65% during the imaging process to simulate a dynamic light source.

[0042] Step 200: splitting the received light containing target object information into transmitted light and reflected light by the beam splitting assembly, and sending the reflected light to a first imaging assembly and the transmitted light to a second imaging assembly; specifically, splitting the light containing target object information into transmitted light and reflected light by a semi-transmissive and semi-reflective beam splitter.

[0043] Step 300, detecting and counting the received reflected light by the first imaging assembly and generating a first pulse signal; modulating, detecting and counting the received transmitted light by the second imaging assembly and generating a second pulse signal; specifically, the reflected light reaches the first single-photon detector after passing through the first converging lens to calibrate the light source intensity; the transmitted light is imaged on the DMD by the optical imaging component, and the light converging coupling assembly and the second single-photon detector are placed in the reflection direction of the DMD.

[0044] Step 400, accumulating the first pulse signal and the second pulse signal by the time-correlated single-photon counting imaging assembly to obtain corresponding calibration signals and image signals.

[0045] Step 500, calibrating the image signal by the time-correlated single-photon counting imaging assembly using the calibration signal, and then reconstructing the target image based on the calibrated image signal and the modulation information.

[0046] In one application example, step 500 includes:

[0047] (1) obtaining the modulation information of the spatial light modulator by the time-correlated single-photon counter.

[0048] (2) accumulating the first pulse signal and the second pulse signal by the time-correlated single-photon counter to obtain analog values of the corresponding calibration signals and analog values of the image signals; specifically, the time-correlated single-photon counter TCSPC counts the total number of photons of the two single-photon detectors and outputs corresponding analog values.

[0049] (3) dividing the analog value of the image signal by the analog value of the calibration signal by the imaging component to obtain the calibrated image signal.

[0050] (4) reconstructing the target image according to the calibrated image signal and the modulation information of the spatial light modulator by the imaging component; specifically, the calibrated image signal is combined with the corresponding modulation matrix to run the imaging on the imaging component by the recovery algorithm.

[0051] In another application example, the high-dynamic photon counting single-pixel imaging method further includes visualizing and displaying the reconstructed target image by the imaging component.

[0052] In summary, the application constructs a high dynamic single-photon counting single-pixel imaging device in a dual-band differential form, divides the light beam containing target object information into two parts, i.e., transmitted light and reflected light, and the reflected light reaches the single-photon detector for calibration of light source intensity after passing through a converging lens; the transmitted light is imaged on the DMD, and a single-photon detector is placed in the reflection direction of the DMD, and the intensity signal after calibration can be obtained by dividing the signal of the single-photon detector for imaging by the signal of the single-photon detector for calibration, as shown in Figure 3 Thus, the light source calibration is realized; finally, the image can be solved according to the intensity signal after calibration and the modulation information of the DMD. Figure 2 Fig. 2 is a schematic diagram of uncalibrated modulation intensity and imaging results, Figure 4 Fig. 3 is a schematic diagram of calibrated modulation intensity and imaging results, and by comparing the two figures, it can be seen that the application reduces the requirement for light source stability and greatly enhances the imaging capability in a complex scene with unstable light source.

[0053] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant regulations.

[0054] The technical features of the above embodiments can be combined arbitrarily, and to make the description concise, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0055] The principles and implementation modes of the application are described by applying specific examples in this paper, and the above embodiment description is only used to help understand the method and its core idea; at the same time, for those skilled in the art, according to the idea of the application, the specific implementation mode and application range will be changed. In summary, the content of the specification should not be understood as a limitation of the application.

Claims

1. A high dynamic photon counting single-pixel imaging device, characterized in that, The high-dynamic photon counting single-pixel imaging device comprises a laser emission assembly, a beam splitting assembly, a first imaging assembly, a second imaging assembly and a time-correlated single photon counting imaging assembly; The laser emission assembly is configured to emit pulsed laser to a target object to be imaged; the target object to be imaged reflects light containing target object information to the beam splitting assembly; The beam splitting assembly is configured to split the received light containing target object information into transmitted light and reflected light, and send the reflected light to the first imaging assembly and the transmitted light to the second imaging assembly; The first imaging assembly is configured to detect and count the received reflected light, and send the generated first pulse signal to the time-correlated single photon counting imaging assembly; the second imaging assembly is configured to modulate, detect and count the received transmitted light, and send the modulation information and the generated second pulse signal to the time-correlated single photon counting imaging assembly; The first imaging assembly comprises a first converging lens and a first single photon detector arranged in sequence; the first converging lens is configured to converge the received reflected light to the first single photon detector; the first single photon detector is configured to detect the light signal converged by the first converging lens, convert it into a first pulse signal, and then send the first pulse signal to the time-correlated single photon counting imaging assembly; The second imaging assembly comprises an optical imaging component, a spatial light modulator, an optical converging coupling assembly and a second single photon detector; The optical imaging component is configured to image the received transmitted light to the spatial light modulator; the spatial light modulator is configured to modulate the received imaging light and send the modulation information to the time-correlated single photon counting imaging assembly; The modulated light is reflected to the optical converging coupling assembly and collected by the optical converging coupling assembly to the second single photon detector; the second single photon detector is configured to detect the light signal reflected by the optical converging coupling assembly, convert it into a second pulse signal, and then send the second pulse signal to the time-correlated single photon counting imaging assembly; The time-correlated single photon counting imaging assembly is configured to: accumulate the first pulse signal and the second pulse signal to obtain corresponding calibration signals and image signals; calibrate the image signals based on the calibration signals and the modulation information, and then reconstruct the target object image.

2. The high dynamic photon counting single-pixel imaging device of claim 1, wherein, The optical converging coupling assembly comprises a quartz flat-convex lens and a fiber coupler.

3. The high dynamic photon counting single pixel imaging apparatus of claim 1, wherein, The spatial light modulator uses a Hadamard matrix as a modulation code.

4. The high dynamic photon counting single-photon imaging device of claim 1, wherein, The time-correlated single photon counting imaging assembly comprises a time-correlated single photon counter and an imaging component arranged in sequence; The time-correlated single photon counter is connected to the spatial light modulator, and is configured to acquire the modulation information of the spatial light modulator; The first pulse signal and the second pulse signal are accumulated to obtain analog values of corresponding calibration signals and analog values of image signals; The imaging component is connected with the time-correlated single photon counter, and the imaging component is used for dividing the analog value of the image signal by the analog value of the calibration signal to obtain a calibrated image signal; and performing target object image reconstruction according to the calibrated image signal and modulation information of the spatial light modulator.

5. The high dynamic photon counting single pixel imaging apparatus according to claim 1, wherein, The laser emission assembly includes a laser, a working wavelength range of the laser is 400nm-2700nm, a repetition frequency of the laser is 40MHz, and an average power range of the laser is 0W-4W.

6. A high dynamic photon counting single-pixel imaging method, characterized in that, The high dynamic photon counting single-pixel imaging method includes: Pulse laser is emitted to a target object to be imaged by a laser emission assembly; the target object to be imaged reflects light containing target object information to a beam splitting assembly; wherein the laser emission assembly randomly adjusts laser power to a preset power range during imaging to simulate a dynamic light source; The light containing target object information received by the beam splitting assembly is divided into transmitted light and reflected light, and the reflected light is sent to a first imaging assembly and the transmitted light is sent to a second imaging assembly; The first imaging assembly detects and counts the received reflected light and generates a first pulse signal; and the second imaging assembly modulates, detects and counts the received transmitted light and generates a second pulse signal; The time-correlated single photon counting imaging assembly accumulates the first pulse signal and the second pulse signal to obtain corresponding calibration signals and image signals; The time-correlated single photon counting imaging assembly calibrates the image signals by using the calibration signals, and then performs target object image reconstruction based on the calibrated image signals and modulation information; The first imaging assembly includes a first converging lens and a first single photon detector arranged in sequence; the first converging lens is used for converging the received reflected light to the first single photon detector; and the first single photon detector is used for detecting the light signal converged by the first converging lens and converting the light signal into a first pulse signal, and then sending the first pulse signal to the time-correlated single photon counting imaging assembly; The second imaging assembly includes an optical imaging component, a spatial light modulator, an optical converging coupling assembly and a second single photon detector; the optical imaging component is used for imaging the received transmitted light to the spatial light modulator; the spatial light modulator is used for modulating the received imaging light and sending modulation information to the time-correlated single photon counting imaging assembly; the modulated light is reflected to the optical converging coupling assembly and coupled and collected to the second single photon detector by the optical converging coupling assembly; and the second single photon detector is used for detecting the light signal returned by the optical converging coupling assembly and converting the light signal into a second pulse signal, and then sending the second pulse signal to the time-correlated single photon counting imaging assembly.

7. The high dynamic photon counting single pixel imaging method according to claim 6, characterized in that, The second imaging assembly includes a spatial light modulator; and the time-correlated single photon counting imaging assembly includes a time-correlated single photon counter and an imaging component arranged in sequence. The image signal is calibrated by the time-correlated single photon counting imaging component using the calibration signal, and then target object image reconstruction is performed based on the calibrated image signal and modulation information, including: The modulation information of the spatial light modulator is obtained by the time-correlated single photon counter; The first pulse signal and the second pulse signal are accumulated by the time-correlated single photon counter to obtain analog values of the corresponding calibration signal and the image signal; The analog value of the image signal is divided by the analog value of the calibration signal by the imaging component to obtain the calibrated image signal; Target object image reconstruction is performed by the imaging component according to the calibrated image signal and the modulation information of the spatial light modulator.

8. The high dynamic photon counting single pixel imaging method according to claim 7, characterized in that, The high-dynamic photon counting single-pixel imaging method further includes visualizing and displaying the reconstructed target object image by the imaging component.

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