Polarization-spectrum coupled ghost modulation infrared system and ghost elimination method

Abstract

The ghost elimination method based on polarization-spectrum coupling of the ghost elimination method of the present application comprises a reflection layer, which reflects the radiation light of an imaged object and generates a ghost signal; a rotatable polarizer, the rotation angle theta is matched with the black phosphorus crystal axis direction of the black phosphorus spectrum polarization coupled infrared photodetector; the black phosphorus spectrum polarization coupled infrared photodetector is sequentially arranged from bottom to top as follows: SiO2 / Si substrate as an insulating support layer, graphene layer on the SiO2 / Si substrate, InSe thin film covering the graphene layer to form a type II heterojunction interface, black phosphorus layer on the InSe thin film as a core photosensitive layer, Cr / Au metal composite electrode deposited on the graphene layer and the black phosphorus layer respectively, the in-plane anisotropy ratio PER(lambda) of the black phosphorus layer changes with the wavelength, and the difference between the light response value I~alpha T 4 / PER(lambda) distinguishes the real signal from the ghost signal, and provides a miniaturized, self-driven ghost elimination system and method.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photoelectric detection, and particularly relates to a ghost shadow regulation infrared system based on polarization-spectrum coupling and a ghost shadow elimination method. BACKGROUND

[0002] With the deep integration of artificial intelligence and photoelectric sensing technology, the application of infrared imaging systems in the fields of automatic driving, intelligent security, environmental monitoring, etc. has entered the stage of large-scale deployment. Especially in complex scenes, the anti-interference ability of infrared detectors is directly related to life safety and public governance efficiency. However, due to the ghost shadow caused by high-reflective surfaces such as glass, water surface, metal, etc., which is highly similar to the real target in terms of thermal radiation intensity and morphological characteristics, has become a core bottleneck restricting high-tech infrared perception. Studies have shown that in the vehicle-mounted infrared night vision system, the high misjudgment rate of virtual images formed by road water or building glass curtain wall reflection leads to the triggering of false braking or obstacle avoidance instructions of the automatic driving system in extreme scenes, which seriously threatens the safety of driving. In the field of border security, the false alarm events caused by water surface reflection heat source in night infrared monitoring are high, which greatly increases the cost of manual verification and delays the efficiency of emergency response. In addition, in medical infrared diagnosis, the reflection of metal surface of instruments may cause deviation of minimally invasive surgery positioning, which directly threatens the safety of clinical operation.

[0003] Current mainstream infrared detection technology relies on single-dimensional spectrum or polarization, which is difficult to separate real targets and virtual image signals in complex reflection scenes. Although traditional algorithms can compensate through multi-frame fusion or deep learning, their limitations of relying on high-power support and prior data labeling make it difficult to meet the real-time, lightweight and universal industrial demands. The new type of infrared photoelectric detector based on spectral polarization coupling reconstructs the target light field characteristics from the physical perception level through the cooperative coupling of multi-dimensional optical parameters, providing a revolutionary technical path for breaking through environmental reflection interference, reducing false alarm rate, etc. It is expected to reshape the reliability boundary of intelligent sensing system terminal and promote the paradigm upgrade in the fields of unmanned systems, public safety and precision medicine.

[0004] The existing structure relies more on single-dimensional detection, and performs ghost shadow elimination through backend algorithm optimization processing.

[0005] Traditional infrared perception schemes have been long limited by high misjudgment rate under environmental reflection interference; and rely on high-power computing and data training, which have insufficient generalization ability in unknown reflection scenes, making it difficult to meet the rigid demands of edge devices for real-time, lightweight and low-power consumption.

[0006] Therefore, how to solve the problems of high misjudgment rate, high algorithm dependence and insufficient generalization ability caused by ghost interference in complex reflection environment by traditional infrared sensing technology, and provide a black phosphorus dual-mode ghost detection and elimination infrared system based on polarization-spectrum coupling and a self-driven ghost elimination method are technical problems to be solved by those skilled in the art. SUMMARY

[0007] The first object of the present application is to realize that the object and ghost of the high-temperature object cannot be distinguished because the detection gap is small, and to solve the problems in the prior art, a photoelectric detector based on the spectral polarization coupling effect of black phosphorus is provided to realize the elimination of ghost through polarization detection.

[0008] To this end, the above object of the present application is achieved by the following technical scheme:

[0009] The ghost modulation infrared system based on polarization-spectrum coupling includes a reflective layer, a rotatable polarizer and a black phosphorus spectral polarization coupling infrared photoelectric detector arranged in order according to the light transmission direction.

[0010] The reflective layer directly faces the imaged object, and the reflected light reversely radiates the light and generates a ghost signal.

[0011] The rotatable polarizer has a rotation angle theta that dynamically matches the black phosphorus crystal axis direction of the black phosphorus spectral polarization coupling infrared photoelectric detector.

[0012] The black phosphorus spectral polarization coupling infrared photoelectric detector receives the polarized modulated light signal, and sequentially includes SiO2 / Si substrate, graphene layer, InSe film and black phosphorus layer from bottom to top. The black phosphorus layer receives the light signal modulated by the rotatable polarizer as a photosensitive layer. The metal composite electrode is deposited on the graphene layer and the black phosphorus layer. The reflected light passes through the polarizer. When the rotatable polarizer is rotated to theta=90°, the light transmission axis is aligned with the zigzag direction ZZ of the black phosphorus, and the ghost signal is eliminated. When theta=0°, the light transmission axis is aligned with the armchair direction AC of the black phosphorus, and the ghost detection is realized. By adjusting the azimuth angle modulation theta=0° / 90° of the rotatable polarizer, the polarization state selectively transmits the spectral coupling of the in-plane anisotropy of the black phosphorus, and the dynamic modulation of the ghost signal is realized.

[0013] While adopting the above technical scheme, the present application can also adopt or combine the following technical scheme:

[0014] As a preferred technical scheme of the present application: after adjusting the light transmission axis of the rotatable polarizer to the ZZ direction, the imaged object signal I3~alphaT1 4 / PER(lambda1) is retained because PER(lambda1) is weak; the ghost signal is suppressed because PER(lambda2) is strong, I4~alphaT2 4 / PER(λ2) →0, to achieve ghost elimination, wherein, alpha is the comprehensive efficiency factor of infrared radiation-electrical signal conversion, lambda1 and lambda2 correspond to the radiation spectrum of the imaged object and ghost respectively, T1 and T2 are the equivalent radiation temperatures of the imaged object and ghost respectively.

[0015] As a preferred technical scheme of the present application: when the polarization is not controlled, the imaged object signal I1~alpha T1 4 ; ghost signal I2~alpha T2 4 Wherein, alpha is the comprehensive efficiency factor of infrared radiation-electrical signal conversion, T1 and T2 are the equivalent radiation temperatures of the imaged object and ghost respectively, the light transmission axis of the rotatable polarizer is adjusted to the AC direction, the absorption of black phosphorus to light in the AC direction is weak, the detector receives the complete reflection signal (I1+I2), at this time, the ghost signal (I2) and the real signal (I1) are detected at the same time.

[0016] As a preferred technical scheme of the present application: a filter is provided, the filter is a band-pass filter, and the filter is arranged at the front end of the incident light path of the polarizer and is used to filter out visible light and near-infrared light with a wavelength <2.5um.

[0017] As a preferred technical scheme of the present application: the detector adopts a layered stacking structure of a vertical light path, and the light signal transmission direction is perpendicular to the plane of each material layer.

[0018] As a preferred technical scheme of the present application: the in-plane anisotropy of black phosphorus is PER(λ).

[0019] As a preferred technical scheme of the present application: the size of the black phosphorus spectral polarization coupled infrared photodetector is 5mm*5mm*1mm.

[0020] The second object of the present application is to provide a ghost elimination method.

[0021] To this end, the above-mentioned object of the present application is realized by the following technical scheme:

[0022] A ghost elimination method, comprising the following steps:

[0023] The rotatable polarizer is switched to theta=90° and aligned with the ZZ direction, the signal is collected, the ghost component I4 / PER(λ2)→0 is suppressed by the high PER(λ) of black phosphorus in the ZZ direction, the polarization state-light intensity correlation control is cooperated with the in-plane anisotropy of black phosphorus PER(λ), and the ghost signal elimination is realized.

[0024] Compared with the prior art, the ghost regulation infrared system and ghost elimination method based on polarization-spectrum coupling have the following beneficial effects: the ghost regulation infrared system and ghost elimination method based on polarization-spectrum coupling realize real-time separation of a target and a ghost from a physical perception layer of a detector by integrating a black phosphorus anisotropy detector and a rotatable polarization filter; the ghost regulation infrared system and ghost elimination method based on polarization-spectrum coupling utilize the double sensitivity of a black phosphorus in-plane low-symmetry structure to polarization and spectrum, combine dynamic polarization modulation with a feature extraction algorithm, and complete ghost suppression at a device level without relying on high-power back-end computing power, and simultaneously have millimeter-level miniaturization and zero-power self-driving characteristics, and can be widely applied to the fields of automatic driving, security monitoring and medical diagnosis, and significantly improve imaging reliability and edge computing adaptability in complex scenes.

[0025] Compared with a traditional conventional split-beam polarization infrared system, the ghost regulation infrared system and ghost elimination method based on polarization-spectrum coupling realize signal detection relying on blackbody Planck radiation emitted by an imaged object and self-driving characteristics of black phosphorus material, can compress the size of the detector to 9 mm, provide a miniaturized and self-driven ghost elimination system and method, and have great application prospects in the fields of automatic driving, security monitoring and medical diagnosis. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 FIG. 1 is a structural schematic diagram of the ghost regulation infrared system based on polarization-spectrum coupling of the present application;

[0027] Figure 2 FIG. 2 is a structural schematic diagram of the ghost regulation infrared system based on polarization-spectrum coupling of the present application;

[0028] Figure 3 FIG. 3 is a black phosphorus anisotropy ratio under different wavelengths;

[0029] Figure 4 FIG. 4 is an imaged image of an imaged radiation object in a ghost elimination imaging experiment of the ghost regulation infrared system based on polarization-spectrum coupling of the present application by a commercial infrared thermal imager;

[0030] Figure 5 FIG. 5 is a practical effect diagram of the ghost regulation infrared system based on polarization-spectrum coupling of the present application in a ghost elimination experiment.

[0031] In the figure, the imaged object 1; the thermal resistance wire 2; the high-reflective layer 3; the rotatable polarizer 4; the black phosphorus spectrum polarization coupling infrared photodetector 5; the Cr / Au metal composite electrode 6; the SiO2 / Si substrate 10; the graphene layer 9; the InSe thin film 8; and the black phosphorus layer 7. DETAILED DESCRIPTION

[0032] The present application is described in further detail with reference to the accompanying drawings and specific embodiments.

[0033] As Figure 1As shown, the present invention provides a ghost-modulated infrared system based on polarization-spectral coupling, comprising a reflective layer 3, a rotatable polarizer 4, and a black phosphorus spectral polarization coupled infrared photodetector 5. The reflective layer, the rotatable polarizer, and the black phosphorus spectral polarization coupled infrared photodetector are arranged sequentially on the same optical axis according to the direction of light transmission.

[0034] The reflective layer 3 faces the object being imaged directly, reflecting the radiation light from the object and generating a ghost signal.

[0035] The rotatable polarizer 4 has a rotation angle θ that matches the black phosphorus crystal axis direction of the black phosphorus spectral polarization coupled infrared photodetector 5. When θ=0°, the polarizer rotates to the armrest direction of the black phosphorus to achieve ghost detection, and when θ=90°, the polarizer rotates to the ZZ direction to achieve ghost elimination.

[0036] The black phosphorus spectral polarization coupled infrared photodetector receives polarization-modulated light signals. From bottom to top, it consists of a SiO2 / Si substrate 10, a graphene layer 9, an InSe thin film 8, and a black phosphorus layer 7. The black phosphorus layer acts as a photosensitive layer to receive light signals modulated by a rotatable polarizer. Metal composite electrodes are deposited on the graphene layer and the black phosphorus layer, respectively. The reflected light from the reflective layer passes through the polarizer. When the rotatable polarizer is rotated to θ=90°, its transmission axis is aligned with the serration direction ZZ of the black phosphorus, and the ghost signal is eliminated. When θ=0°, its transmission axis is aligned with the armrest direction AC of the black phosphorus, achieving ghost detection. By modulating the azimuth angle of the rotatable polarizer to θ=0° / 90°, the polarization-selective transmission and the in-plane anisotropic spectral coupling of the black phosphorus enable dynamic control of the ghost signal.

[0037] like Figure 2 As shown, the black phosphorus spectral polarization coupled infrared photodetector of the present invention comprises, from bottom to top: a SiO2 / Si substrate 10 as an insulating support layer; a graphene layer 9 on the SiO2 / Si substrate; an InSe thin film 8 covering the graphene layer 9 to form a type II heterojunction interface; a black phosphorus layer 7 on the InSe thin film 8 as a core photosensitive layer; and Cr / Au metal composite electrodes 6 deposited on the graphene layer 9 and the black phosphorus layer 7, respectively. The detector adopts a layered stacked structure with a perpendicular optical path, and the optical signal transmission direction is perpendicular to the plane of each material layer. The photoresponse value I~αT is obtained by utilizing the characteristic of the anisotropy ratio PER(λ) within the black phosphorus layer varying with the wavelength. 4 The difference in PER(λ) distinguishes between real and ghost signals. The in-plane anisotropy ratio PER(λ) of black phosphorus is:

[0038] The graphene layer 9 and the black phosphorus layer 7 are not in direct contact. After the transmission axis of the rotatable polarizer is adjusted to the ZZ direction, the imaged object signal I3~αT1 is captured. 4 / PER(λ1) difference reservation; ghost signal is suppressed due to PER(λ2) enhancement, I4~αT2 4 / PER(λ2) →0, ghost elimination is achieved, wherein, alpha is the comprehensive efficiency factor of infrared radiation-electrical signal conversion, lambda1 and lambda2 correspond to the radiation spectrum of the imaged object and the ghost respectively, T1 and T2 are the equivalent radiation temperatures of the imaged object and the ghost respectively.

[0039] When the polarization is not controlled, the imaged object signal I1~αT1 4 ; ghost signal I2~αT2 4 Wherein, alpha is the comprehensive efficiency factor of infrared radiation-electrical signal conversion, T1 and T2 are the equivalent radiation temperatures of the imaged object and the ghost respectively, the transmission axis of the rotatable polarizer is adjusted to the AC direction, the absorption of black phosphorus to light in the AC direction is weak, the detector receives the complete reflection signal (I1+I2), at this time, the ghost signal (I2) and the real signal (I1) are detected at the same time.

[0040] The polarization state control of the azimuth angle modulation theta=0° / 90° of the rotatable polarizer and the anisotropy PER(λ) of the black phosphorus spectrum are cooperated, the ghost signal is dynamically distinguished and suppressed by using the response difference of I~alphaT / PER(λ), and the real target information is reserved.

[0041] Based on the dynamic switching of the rotation angle theta of the polarizer, the chair / ZZ direction alignment, the polarization state-light intensity correlation control and the cooperation of the in-plane anisotropy of the black phosphorus PER(λ), the programmable suppression of the ghost signal is realized.

[0042] The polarization-spectrum coupled ghost control infrared system further has a filter, the filter is a band-pass filter, and is arranged at the front end of the incident light path of the polarizer and is used for filtering out visible light and near-infrared light with a wavelength of less than 2.5 microns.

[0043] The size of the black phosphorus spectrum polarization coupled infrared photodetector is 5mm*5mm*1mm.

[0044] The self-driven ghost elimination method of the polarization-spectrum coupled ghost control infrared system includes the following steps:

[0045] The rotatable polarizer is switched to theta=90° and is aligned with the ZZ direction, the signal is collected, the ghost component I4 / PER(λ2) is suppressed by using the high PER(λ) of the black phosphorus in the ZZ direction, the polarization state-light intensity correlation control and the cooperation of the in-plane anisotropy of the black phosphorus PER(λ) are cooperated, and the ghost signal elimination is realized.

[0046] The polarization-spectrum coupled ghost control infrared system and the ghost elimination method of the application have the following beneficial effects:

[0047] Compact: removing the filter can reduce the volume, suitable for integrated applications, such as unmanned aerial vehicle infrared imaging;

[0048] Dynamic adaptation: real-time switching of detection / elimination mode by rotating the polarizer;

[0049] Multispectral potential: combined with the continuous change of anisotropy ratio of black phosphorus with wavelength, it is possible to realize multispectral detection without filter.

[0050] Embodiment 1

[0051] As shown in Figure 1 , in the ghost elimination method of the present application based on polarization-spectrum coupling, the schematic diagram for realizing ghost elimination is shown in the figure, the imaged object 1 is a thermal resistance wire, behind the resistance wire there is a high reflection layer 3, which is a metal reflection net, through the metal reflection net the resistance wire exists the imaged object 1 and the ghost 2, in the detection of realizing ghost elimination, among which the filter is set to eliminate the interference of visible light, only need to place the polarizer 4 in front of the black phosphorus spectrum polarization coupling infrared photodetector 5, rotate the angle of the polarizer to the ZZ direction of the black phosphorus spectrum polarization coupling infrared photodetector 5, the obtained imaging diagram is shown in Figure 4 , that is, the ghost in the imaged object can be eliminated.

[0052] As shown in Figure 2 , the black phosphorus spectrum polarization coupling infrared photodetector of the present application, benefits from the anisotropy of black phosphorus itself which changes with wavelength as shown in Figure 3 , the anisotropy ratio corresponding to each wavelength is different, thus the intensity of polarization detection at different blackbody temperatures will also change, for example, under normal circumstances, the blackbody of 1000K and the blackbody of 900K, other conditions being unchanged, the light response value of black phosphorus I ~ αT4, if the ZZ direction is detected, that is, the polarizer is rotated by 90°, then the light response value of black phosphorus I ~ αT4 / PER (λ), wherein PER is the extinction ratio of the device as shown in Figure 3 ; and the anisotropy ratio of different temperatures is quite different, the ghost is red-shifted compared with the object due to reflection and other reasons, that is, the anisotropy ratio is larger, then according to the above formula, PER (λ) is large, and the actual light response value is small.

[0053] The polarizer and the black phosphorus spectrum polarization coupling infrared photodetector realize the elimination of ghost by rotating the polarizer to the ZZ direction in the black phosphorus plane as shown in Figure 5 , the in-plane direction of black phosphorus can be judged by the size of photocurrent.

[0054] Among them, and the device size is ≤9mm.

[0055] The above detailed description is merely exemplary in nature and is not intended to limit the application as described herein. Any modification or equivalent arrangement within the spirit or scope of the application should be considered to fall within the scope of the application.

Claims

1. A ghost signal regulation infrared system based on polarization-spectrum coupling, characterized in that: it comprises, in order along the light signal transmission direction, a reflective layer, a rotatable polarizer, and a black phosphorus spectrum polarization coupling infrared photodetector; the reflective layer directly faces the imaged object, reflects the light and generates a ghost signal; the rotatable polarizer dynamically matches the black phosphorus crystal axis direction of the black phosphorus spectrum polarization coupling infrared photodetector; the black phosphorus spectrum polarization coupling infrared photodetector receives the polarized light signal, and comprises, from bottom to top, a Si / SiO2 substrate, a graphene layer, an InSe film, and a black phosphorus layer, the black phosphorus layer serving as a photosensitive layer and being capable of receiving the polarized light signal modulated by the rotatable polarizer, a metal composite electrode is deposited on the graphene layer and the black phosphorus layer respectively, the reflective layer reflects the light through the rotatable polarizer, when the rotatable polarizer is rotated to θ = 90°, the light transmission axis thereof is aligned with the zigzag direction ZZ of the black phosphorus, and the ghost signal is eliminated; when θ = 0°, the light transmission axis thereof is aligned with the armchair direction AC of the black phosphorus, and ghost detection is achieved, the azimuth angle modulation θ = 0° / 90° of the rotatable polarizer, the polarization state selective transmission, and the in-plane anisotropic spectrum coupling of the black phosphorus are combined to realize dynamic regulation of the ghost signal.

2. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: The light transmission axis of the rotatable polarizer is adjusted to the zigzag direction ZZ of black phosphorus, and the signal I3~αT1 of the imaged object is obtained 4 PER(λ1) is weakly retained; the ghost signal is suppressed due to strong PER(λ2), and I4~αT2 is obtained 4 PER(λ2)→0, ghost elimination is achieved, wherein α is a comprehensive efficiency factor of infrared radiation-electrical signal conversion, λ1 and λ2 correspond to the radiation peak wavelengths of the imaged object and the ghost respectively, and T1 and T2 are the equivalent radiation temperatures of the imaged object and the ghost respectively.

3. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: Unpolarized control, the imaged object signal I1~αT1 4 ; ghost signal I2~αT2 4 Wherein, α is the comprehensive efficiency factor of infrared radiation-electric signal conversion, T1 and T2 are the equivalent radiation temperatures of the imaged object and the ghost respectively, the black phosphorus is weak in the absorption of light in the armchair direction AC direction of the black phosphorus after the transmission axis of the rotatable polarizer is adjusted to the armchair direction AC direction of the black phosphorus, the black phosphorus spectral polarization couples the infrared photodetector to receive the complete reflected signal I1+I2, at this time, the ghost signal I2 and the imaged object signal I1 are detected simultaneously.

4. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: A filter is provided, which is a band-pass filter and is arranged at the front end of the incident light path of the rotatable polarizer to filter out visible light and near-infrared light with a wavelength < 2.5 μm.

5. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: The black phosphorus spectrum polarization coupling infrared photodetector adopts a layered stack structure with a vertical light path, and the light signal transmission direction is perpendicular to the plane of each material layer.

6. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: The metal composite electrode is a Cr / Au metal composite electrode.

7. The polarization-spectrally coupled ghost- managed infrared system of claim 1, wherein: The size of the black phosphorus spectrum polarization coupling infrared photodetector is 5 mm × 5 mm × 1 mm.

8. The method of ghost cancellation for a polarization-spectrally coupled ghost- managed infrared system according to any of claims 1-5, characterized in that: It comprises the following steps: switch the rotatable polarizer to θ = 90° and align it with the zigzag direction ZZ of the black phosphorus, collect the signal, utilize the high PER(λ) ghost component I4 / PER(λ2)→0 in the ZZ direction of the black phosphorus, and the synergistic effect of the polarization state-spectrum coupling and the in-plane anisotropy ratio PER(λ) of the black phosphorus to realize ghost signal elimination.

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