阅读说明：本技术 一种α放射源光学成像检测系统及其检测方法 (Alpha radioactive source optical imaging detection system and detection method thereof ) 是由 李峰生 朱亚 王国强 江其生 东肃河 李治桦 陈忠民 于 2020-06-30 设计创作，主要内容包括：本发明公开了一种α放射源光学成像检测系统及其检测方法。光学系统用于接收紫外光,并将接收到的紫外光传输给图像传感器,图像传感器将接收到的紫外光信号转换为电信号,并传输给图像信号处理器ISP,图像信号处理器ISP用于图像处理,图像信号处理器ISP将电信号处理后传输至数字信号处理器DSP,数字信号处理器DSP用于对α粒子探测微光相机的控制,将控制后的结果经由输出电路传输至计算机。用电子倍增微光相机探测α辐射发光与可见光图像配准融合,输出可供检测人员清晰辨识的α放射源位置分布和放射强度指示的图像,提高α放射源检测效率和定位精度,降低检测人员劳动强度和辐射风险,提高放射性物质检测与管控能力。(The invention discloses an alpha radioactive source optical imaging detection system and a detection method thereof. The optical system is used for receiving ultraviolet light and transmitting the received ultraviolet light to the image sensor, the image sensor converts a received ultraviolet light signal into an electric signal and transmits the electric signal to the image signal processor ISP, the image signal processor ISP is used for image processing, the image signal processor ISP processes the electric signal and transmits the processed electric signal to the digital signal processor DSP, the digital signal processor DSP is used for controlling the alpha particle detection micro-optic camera, and a controlled result is transmitted to the computer through the output circuit. The electron multiplication micro-optic camera is used for detecting alpha radiation luminescence and registering and fusing with visible light images, and outputs alpha radiation source position distribution and radiation intensity indicated images which can be clearly identified by detection personnel, so that the detection efficiency and the positioning precision of an alpha radiation source are improved, the labor intensity and the radiation risk of the detection personnel are reduced, and the detection and control capability of radioactive substances is improved.)

1. The alpha radioactive source optical imaging detection system is characterized by comprising a visible light camera, an alpha particle detection micro-light camera, an electronic refrigerator and a computer, wherein the visible light camera and the alpha particle detection micro-light camera respectively transmit an alpha radioactive source visible light image signal and an ultraviolet light image signal to the computer, and the electronic refrigerator is arranged on the outer surface of the alpha particle detection micro-light camera;

the alpha particle detection micro-light camera comprises an optical system, an image sensor, an image signal processor ISP, a digital signal processor DSP and an output circuit, wherein the optical system is used for receiving ultraviolet light and transmitting the received ultraviolet light to the image sensor, the image sensor converts a received ultraviolet light signal into an electric signal and transmits the electric signal to the image signal processor ISP, the image signal processor ISP is used for image processing, the image signal processor ISP processes the electric signal and then transmits the electric signal to the digital signal processor DSP, the digital signal processor DSP is used for controlling the alpha particle detection micro-light camera, and a controlled result is transmitted to a computer through the output circuit.

2. The system as claimed in claim 1, wherein the electronic refrigerator is used to cool the EMCMOS sensor of the alpha-particle detection micro-optic camera.

3. The system of claim 1, wherein the image processing is exposure control, denoising filter, gain control, dead pixel correction, strong light suppression, backlight compensation, image enhancement, and lens shading correction of the image.

4. The optical imaging detection system for alpha radioactive source according to claim 1, wherein an interference band pass filter and a CaF2/MgF2 UV lens are disposed in the optical system, and the interference band pass filter is disposed at a distance of 1mm from the CaF2/MgF2 UV lens.

5. The detection method of the alpha radioactive source optical imaging detection system is characterized by comprising the following steps:

step 1: determining initial condition parameters, wherein the initial parameters are background ultraviolet illumination level, quantum efficiency of a micro-optic camera sensor, amplification factor of a reading circuit of the micro-optic camera, and inherent noise level of the micro-optic camera sensor;

step 2: based on the initial condition of the step 1, when the ultraviolet light signal is at the single photon level, calibrating the visible light camera and the alpha particle detection micro-light camera together in an image calibration mode and capturing the ultraviolet light;

and step 3: in a computer, an alpha radiation source ultraviolet image is superposed and displayed on an alpha radiation source visible image in a pseudo-color mode;

and 4, step 4: and (4) observing and recording the characteristics of the ultraviolet light obtained in the step (3), so as to judge the existence and the quantity of the radioactive nuclides.

6. The detecting method of the α -ray source optical imaging detecting system according to claim 5, wherein the background ultraviolet illumination level, the quantum efficiency of the low-light-level camera sensor, the amplification factor of the low-light-level camera readout circuit and the intrinsic noise level of the low-light-level camera sensor are set in the step 1 within a predetermined range.

7. The detecting method for the α radioactive source optical imaging detecting system, according to claim 6, wherein the range of the background UV illumination level in step 1 is<The range of quantum efficiencies for a 1mil dian, low-light camera sensor is>95%, the range of the amplification factor of the reading circuit of the low-light camera is>1000 times, the range of the intrinsic noise level of the low-light camera sensor is<10e^-1。

8. The detecting method of an α -ray source optical imaging detecting system according to claim 5, wherein the step 2 is that the captured ultraviolet light is irradiated on an image sensor through an optical system of an α -particle detection micro-optic camera, the image sensor converts an ultraviolet light signal into an electrical signal, so that an image signal processor ISP processes the image signal, and the electrical signal processed by the image signal processor ISP is transmitted to a computer through a control and output circuit of a digital signal processor.

9. The detecting method of an α -ray source optical imaging detecting system according to claim 5, wherein the image calibration in step 2 is performed by calibrating the internal reference and the external reference of two cameras, registering and aligning the ultraviolet image and the visible light image, and the image registration formula is,

in the formula u_R 、v_R 、z_RIs composed ofα three-dimensional coordinates of micro-light camera for particle detection，u_L 、v_L 、z_LIs composed ofThree-dimensional coordinates of visible light camera，r₁₁Is composed ofIntermediate parameters in transformation matrices。

Technical Field

The invention belongs to the technical field of optical imaging; in particular to an alpha radioactive source optical imaging detection system and a detection method thereof.

Background

Because the radiation distance of the alpha radioactive source is extremely short, various detection means at present must be carried out in a short distance (within 1 cm) without contact, and the penetration performance of the alpha radioactive source is poor, so that a protective film cannot be covered outside the existing detection instrument. Once the test is performed and the equipment is in contact with the test, the test instrument may be contaminated and may not be reused before being cleaned again.

Disclosure of Invention

The invention provides an alpha radioactive source optical imaging detection system and a detection method thereof, which uses an electron multiplication micro-optic camera to detect alpha radiation luminescence and register and fuse with visible light images, outputs alpha radioactive source position distribution and radioactive intensity indicated images which can be clearly identified by detection personnel, improves the detection efficiency and positioning precision of an alpha radioactive source, reduces the labor intensity and radiation risk of the detection personnel, and improves the detection and control capability of radioactive substances.

The invention is realized by the following technical scheme:

an alpha radioactive source optical imaging detection system comprises a visible light camera, an alpha particle detection micro light camera, an electronic refrigerator and a computer, wherein the visible light camera and the alpha particle detection micro light camera respectively transmit an alpha radioactive source visible light image signal and an ultraviolet light image signal to the computer, and the electronic refrigerator is arranged on the outer surface of the alpha particle detection micro light camera;

the alpha particle detection micro-light camera comprises an optical system, an image sensor, an image signal processor ISP, a digital signal processor DSP and an output circuit, wherein the optical system is used for receiving ultraviolet light and transmitting the received ultraviolet light to the image sensor, the image sensor converts a received ultraviolet light signal into an electric signal and transmits the electric signal to the image signal processor ISP, the image signal processor ISP is used for image processing, the image signal processor ISP processes the electric signal and then transmits the electric signal to the digital signal processor DSP, the digital signal processor DSP is used for controlling the alpha particle detection micro-light camera, and a controlled result is transmitted to a computer through the output circuit.

Further, the electronic refrigerator refrigerates an EMCMOS sensor of the alpha particle detection micro-optic camera.

Further, the image processing includes exposure control, denoising and filtering, gain control, dead pixel correction, strong light suppression, backlight compensation, image enhancement and lens shading correction of the image.

Furthermore, an interference band-pass filter and a CaF2/MgF2 ultraviolet lens are arranged in the optical system, and the distance between the interference band-pass filter and the CaF2/MgF2 ultraviolet lens is 1 mm.

A detection method of an alpha radioactive source optical imaging detection system comprises the following steps:

step 1: determining initial condition parameters, wherein the initial parameters are background ultraviolet illumination level, quantum efficiency of a micro-optic camera sensor, amplification factor of a reading circuit of the micro-optic camera, and inherent noise level of the micro-optic camera sensor;

step 2: based on the initial condition of the step 1, when the ultraviolet light signal is at the single photon level, calibrating the visible light camera and the alpha particle detection micro-light camera together in an image calibration mode and capturing the ultraviolet light;

and step 3: in a computer, an alpha radiation source ultraviolet image is superposed and displayed on an alpha radiation source visible image in a pseudo-color mode;

and 4, step 4: and (4) observing and recording the characteristics of the ultraviolet light obtained in the step (3), so as to judge the existence and the quantity of the radioactive nuclides.

Further, the background ultraviolet illumination level, the quantum efficiency of the low-light-level camera sensor, the amplification factor of the reading circuit of the low-light-level camera, and the inherent noise level of the low-light-level camera sensor are respectively set in the preset range in the step 1.

Further, the range of the background ultraviolet illumination level in the step 1 is<The range of quantum efficiencies for a 1mil dian, low-light camera sensor is>95%, the range of the amplification factor of the reading circuit of the low-light camera is>1000 times, the range of the intrinsic noise level of the low-light camera sensor is<10e^-1。

Further, the step 2 is that the captured ultraviolet light is irradiated on the image sensor through an optical system of the alpha particle detection micro-light camera, the image sensor converts an ultraviolet light signal into an electric signal, the image signal is processed by the image signal processor ISP, and the electric signal is processed by the image signal processor ISP and then transmitted to the computer through a control and output circuit of the digital signal processor.

Further, the image calibration in step 2 is performed by calibrating the internal reference and the external reference of the two cameras, registering and aligning the ultraviolet image and the visible light image, wherein the image registration formula is as follows,

in the formula (I), the compound is shown in the specification, _{R R R L L L}u, v and z are α three-dimensional coordinates of the particle detection micro-light camera, and u, v and z are three-dimensional coordinates of the visible light camera ₁₁And r is an intermediate parameter in the transformation matrix.

The invention has the beneficial effects that:

the collision of the radionuclide alpha particles with nitrogen (the collision of the alpha particles with air molecules induces the air to radiate light, which is mainly emitted by the nitrogen molecules) can emit weak ultraviolet light with obvious characteristics, the light is amplified and collected by a photoelectric means, the characteristics of the ultraviolet light are observed and recorded, and the existence and the quantity of the radionuclide can be judged; results can be obtained while observation, and the reaction time and the curing time are greatly shortened.

Drawings

FIG. 1 is a block diagram of an optical imaging detection system for alpha radioactive source.

FIG. 2 is a block diagram of a micro-optic camera for detecting alpha particles

Fig. 3 is an exemplary image fusion diagram.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.