CN112492300B - Polarization spectrum camera detector and detection method - Google Patents
Polarization spectrum camera detector and detection method Download PDFInfo
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- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
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Abstract
The invention relates to a polarization spectrum camera detector and a detection method, belonging to the field of calibrating cameras by using an optical lossless means. The structure comprises: the device comprises a light source generating module, a light source modulating module, a data acquisition and processing module, a power supply control module and an optical darkroom, and the detection method comprises the following steps: 1. initializing a camera and an optical path; 2. modulating the intensity and wavelength of an incident light source of the camera; 3. collecting image data; 4. calculating quality parameters of the camera by utilizing an algorithm according to the image data acquired in the step three; 5. and (3) changing the polarization state of incident light and the intensity and wavelength of the light source, and repeating the third and fourth steps to finish the quality parameter detection of the camera in the polarized light state. The method improves the quality and the variety of the detection light source, and solves the problems of low efficiency of the integrating sphere, over-high temperature of the integrating sphere, insufficient intensity of the calibration light source and the like caused by the fact that a bromine tungsten lamp is arranged in the existing camera detector.
Description
Technical Field
The invention belongs to the field of calibrating cameras by using an optical lossless means, and particularly relates to a polarization spectrum camera detector and a detection method.
Background
The existing spectrum camera detectors are mainly divided into two types, namely, an integrating sphere and a parallel light pipe are used for generating parallel area array light to scale the camera, and the method can cause the following problems due to the fact that a light source is directly arranged in the integrating sphere: 1. the larger the ratio of the total area of the built-in bromine tungsten lamp to the inner surface area of the integrating sphere is, the lower the light homogenizing effect of the integrating sphere is, in order to solve the problem, a large-sized integrating sphere is generally adopted or the intensity value of a light source is reduced, but the adoption of the large-sized integrating sphere can lead to the great increase of the cost, the reduction of the intensity of the light source also leads to the reduction of the light intensity due to the fact that the collimator itself can reduce the light intensity, so that the incident light intensity of the final camera cannot meet the calibration requirement; 2. as the light source generally used for calibration is a bromine tungsten lamp, the bromine tungsten lamp is a thermal light source, a large amount of heat is generated when the bromine tungsten lamp emits light, the temperature of the integrating sphere is overhigh and is an accumulation process when the bromine tungsten lamp is arranged in the integrating sphere to work, the temperature of the integrating sphere is higher and higher along with the increase of time, the calibration precision is reduced, the calibration time is greatly reduced, the light source intensity is reduced, and the light intensity is reduced due to the fact that the collimator itself reduces the incident light intensity of the last camera, so that the calibration requirement cannot be met; 3. because the response of the camera to different wavelengths is inconsistent, only various mixed lights can be obtained to scale the camera by using an integrating sphere and collimator method, and the scaling precision and the using effect of scaling parameters can be greatly reduced. The method solves the problem of built-in light source of the integrating sphere, but because the single external halogen lamp has larger volume and low light source intensity, the emergent light from the integrating sphere is not parallel to each other, the light sources can influence each other when the camera is calibrated, the received incident light intensity of each pixel point of the camera is inconsistent, and the further the camera is away from the monochromator, the worse the calibration effect is, and the like.
Disclosure of Invention
Aiming at the defects and defects of the prior art, the invention provides a polarization spectrum camera detector and a detection method, which concretely comprise the following steps:
a polarization spectrum camera detector, comprising: a light source generating module, a light source modulating module, a data acquiring and processing module, a power control module 12 and an optical darkroom 13;
wherein, the light source produces the module and includes: integrating sphere A1, monochromator 2 and integrating sphere B3, integrating sphere A1, integrating sphere B3 of monochromator 2 are connected sequentially, light source is installed in integrating sphere A1, and strong light illuminometer is installed on integrating sphere B3;
the light source modulation module includes: a polarizer 4, a 1/2 lambda plate 5, a 1/4 lambda plate 6, a target 7 and a collimator 8;
the data acquisition and processing module comprises: a camera 9, a multi-dimensional displacement table 10 and a computer 11;
the central axis of the light source generating module, the light source modulating module and the data acquiring and processing module is kept on a horizontal line, the power supply control module 12 is connected with the integrating sphere A1, the optical darkroom 13 is of a shell structure, the left end of the optical darkroom is provided with a light inlet c, one end of the integrating sphere B3 is connected with the light source modulating module through the light inlet c, and the light source modulating module and the data acquiring and processing module are arranged inside the shell structure of the optical darkroom 13.
Further, the integrating sphere A1 is provided with six openings, five of the openings are light source placing openings, one opening is a light outlet, 1 halogen lamp is placed in each light source placing opening, each halogen lamp is provided with a cylindrical lampshade, and each lampshade is fixedly connected to the light source placing opening of the integrating sphere A1.
Further, the monochromator 2 is provided with an electric filter wheel, a grating structure and a light outlet slit.
Further, the integrating sphere B3 is provided with 4 openings in total, and the integrating sphere comprises a light inlet B, a light outlet B, a detection opening for placing a strong light illuminometer probe and a standby opening, wherein the standby opening and the light inlet B are vertically symmetrical, and the strong light illuminometer is installed at the detection opening of the strong light illuminometer probe.
Further, the light outlet a is connected with the electric filter wheel, the light outlet slit is connected with the light inlet B, the light outlet B enters the optical darkroom 13, the light enters the monochromator 2 from the light outlet a of the integrating sphere A1 to become quasi-monochromatic light, enters the light inlet B of the integrating sphere B3 to become uniform light, then enters the polarizer 4 in the optical darkroom 13 from the light outlet B of the integrating sphere B3 to become polarized light, and then enters the 1/2 lambda wave plate 5 again to enter the 1/4 lambda wave plate 6 to form linearly polarized light, circularly polarized light and elliptically polarized light to be incident on the target 7.
Further, the light emitted from the target 7 enters the collimator 8, and the light is converted into parallel light by the collimator 8 and then enters the camera 9 on the multi-dimensional displacement table 10.
Further, the multi-dimensional displacement table 10 and the camera 9 adjust the horizontal front-back and horizontal left-right positions of the camera through the multi-dimensional displacement table 10, and adjust the three-dimensional space position of the camera through adjusting the horizontal height of the camera 9; the camera 9 is connected to a computer 11 via a data connection.
The detection method applied to the polarization spectrum camera detector comprises the following steps:
firstly, initializing a camera and an optical path, opening an optical darkroom 13, and removing a polarizer 4, a 1/2 lambda plate 5 and a 1/4 lambda plate 6;
modulating the intensity and wavelength of an incident light source of a camera;
step three, collecting image data;
step four, calculating quality parameters of the camera by utilizing an algorithm according to the image data acquired in the step three;
and fifthly, changing the polarization state of incident light, the intensity and the wavelength of a light source, putting the light source into a polarizer 4, a 1/2 lambda wave plate 5 and a 1/4 lambda wave plate 6, and repeating the third step and the fourth step to finish the quality parameter detection of the camera in the polarized light state.
Further, the initializing the setting in the first step specifically includes: the power supply control module 12 is powered on, the computer 11 is started, the monochromator 2 is started, the intensity of a light source in the integrating sphere A1 and the monochromator 2 are regulated, light rays can be received on the integrating sphere B3, the position of the collimator 8 is fixed, the emergent light of the collimator 8 is filled in the light incident surface of the camera 9, and the light incident surface of the camera 9 is parallel to the light emergent surface of the collimator 8 through the multi-dimensional displacement table 10.
Further, the specific method for modulating the intensity and wavelength of the incident light source of the camera in the second step is as follows: the light source brightness starts to increase until the camera incident light reaches a half-saturated condition, and a wavelength-light source intensity graph is acquired.
Further, the quality parameters in the fourth step include: camera sensitivity, camera sharpness, camera signal-to-noise ratio, and camera non-uniformity.
Further, the signal-to-noise ratio calculating method of the camera comprises the following steps:
the camera Gray values Gray (m, n) are read in the absence of illumination and in the semi-saturated illumination, m representing the rows and n representing the columns. Calculated according to the following formula:
wherein the signal-to-noise ratio is equal to the average signal gray value F (G) under the half-saturated illumination condition signal Mean square error F (G) with gray value under no illumination noise Is multiplied by a coefficient by taking the logarithm of the base 1020。
Further, the method for calculating the non-uniformity of the camera comprises the following steps:
the camera's non-uniformity parameter may be characterized by a value of the light response non-uniformity. Let M, N be the number of rows and columns of the image, a and b be the row index and column index of the array, respectively, then the average digital signal value of the image under no illumination and fifty percent saturated illumination of the Mth row, N column is y dark And y 50 Wherein μ is y,dark Sum mu y,50 Specific calculation methods are shown as formula (4) and formula (5) for average signal values under no illumination and fifty percent saturated illumination
S 2 y,dark And S is 2 y,50 The specific calculation method is as follows, equation (6) and equation (7):
wherein M, N are the number of rows and columns of the image respectively, a and b are the row index and the column index of the array respectively;
the PRNU is a value of the optical response unevenness, and as shown in equation 8, the value of the camera unevenness parameter can be obtained by the optical response unevenness value corresponding to a single wavelength.
Further, the method for calculating the sensitivity of the camera comprises the following steps:
wherein mu y，10 Image average digital signal value under ten percent saturated illumination condition, E 10 And E is 50 An incident light intensity value of the camera under ten percent of saturated illumination condition and fifty percent of saturated illumination condition, S y,dark The root mean square value of the camera image under the condition of no incident light, V is the sensitivity value of the camera, E th Is the lowest illumination value of the camera.
Further, the specific method for changing the polarization state and the light source intensity and the wavelength of the incident light in the fifth step is to open the optical darkroom 13, put the polarizer 4, the 1/2 lambda plate 5 and the 1/4 lambda plate 6, modulate the incident light of the camera into linear polarized light, circular polarized light and elliptical polarized light, and modulate the light source intensity of the incident light of the camera under the condition respectively.
Compared with the existing spectrum camera detection device, the polarization spectrum camera detector and the detection method provided by the invention adopt the devices of integrating sphere, monochromator, integrating sphere, polaroid and parallel light pipe to generate planar array parallel light, so that the quality and the variety of a detection light source are improved, meanwhile, the problems of reduced integrating sphere efficiency, overhigh integrating sphere temperature, insufficient calibration light source intensity and the like caused by the fact that a bromine tungsten lamp is arranged in the existing camera detector are solved, the problems of interaction between integrating sphere efficiency and integrating sphere temperature and light are compatible, meanwhile, the problem of accurate calibration of different responses of a camera to different wavelengths is solved, the polarized light is used for calibrating the camera, the single working time length of the detector is prolonged, the working efficiency is improved, the camera detection cost is reduced, and the large market popularization space is realized.
Drawings
The invention is further described in the following description and detailed description with reference to the drawings:
fig. 1 is a diagram of a structure of a polarization spectrum camera detector.
In the figure: 1-integrating sphere a; 2-monochromator; 3-integrating sphere B; 4-polarizer; a 5-1/2 lambda plate; a 6-1/4 lambda plate; 7-target; 8-parallel light pipes; 9-camera; 10-a multi-dimensional displacement table; 11-a computer; 12-a power control module; 13-optical darkroom.
Detailed Description
The invention will be described in further detail with reference to the drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Embodiment one: in order to demonstrate the applicability of the present invention, a detailed description is given with reference to examples. The present invention may be applied to camera calibration methods other than the examples employed at this time.
The experimental device related to the device of the invention is shown in fig. 1, and the device is characterized in that the device comprises: a light source generating module, a light source modulating module, a data acquiring and processing module, a power control module 12 and an optical darkroom 13; wherein, the light source produces the module and includes: integrating sphere A1, monochromator 2 and integrating sphere B3, integrating sphere A1, integrating sphere B3 of monochromator 2 are connected sequentially, light source is installed in integrating sphere A1, and strong light illuminometer is installed on integrating sphere B3; the light source modulation module includes: a polarizer 4, a 1/2 lambda plate 5, a 1/4 lambda plate 6, a target 7 and a collimator 8; the data acquisition and processing module comprises: a camera 9, a multi-dimensional displacement table 10 and a computer 11; the central axis of the light source generating module, the light source modulating module and the data acquiring and processing module is kept on a horizontal line, the power supply control module 12 is connected with the integrating sphere A1, the optical darkroom 13 is of a shell structure, the left end is provided with a light inlet c, one end of the integrating sphere B3 enters the light inlet c and is connected with the light source modulating module, and the light source modulating module and the data acquiring and processing module are arranged inside the shell structure of the optical darkroom 13.
Six openings are formed in the integrating sphere A1, five of the openings are light source placing openings, one opening is a light outlet, each light source placing opening is a cylinder with a curved surface on the lower surface, the curved surface can be just placed on the outer spherical surface of the integrating sphere A1, a round groove is formed in the upper surface of the center of the cylinder, and 1 halogen lamp can be just buckled on the groove. Each halogen lamp is arranged in a cylindrical lampshade, a small hole is formed in the upper surface of the cylindrical lampshade for placing a power line to pass through, and the lower surface of each cylindrical lampshade is fixedly connected with the upper surface of a cylinder with a curved surface. The cylindrical surface of the cylindrical lampshade is provided with a strip-shaped long hole. The invention has the following functions: the small hole on the upper surface of the column type lampshade allows the power line to pass through, and the illumination intensity of the halogen lamp is regulated by changing the voltage; the cylindrical surface of the cylindrical lampshade is provided with a strip-shaped long hole, which has the functions that: in order to enhance the heat radiation function when the halogen lamp works, the cylindrical lampshade ensures the heat radiation and the safety of operators.
Light emitted from a light outlet a on the integrating sphere 1 enters an optical filter wheel of the monochromator 2 and then enters an incident light slit of the monochromator 2, monochromatic light with single wavelength is obtained under the action of a multi-stage grating in the monochromator 2, and the modulated monochromatic light is connected with a light inlet on the integrating sphere B3 from the light outlet slit of the light outlet slit on the monochromator 2 through a light source conversion block; the monochromator 3 is connected with a host computer of the computer 11 through a data line, and can directly change the filtering efficiency of the filter wheel and select the passing grating on the computer through a software control program to control the wavelength of emergent monochromatic light.
The integrating sphere B3 is provided with 4 openings, and comprises an optical inlet, an optical outlet, a detection opening for placing a strong light illuminometer probe and a standby optical inlet, wherein the standby opening and the optical inlet are arranged on a hemispherical surface and are vertically symmetrical on the same horizontal plane. Through the light outlet on integrating sphere B3 into polarizer 4 in optical darkroom 13.
The polarized light is changed from the polarizer 4 into polarized light and enters the 1/2 lambda plate 5, only the vibration direction of the polarized light is changed, the linearly polarized light from the 1/2 lambda plate 5 only changes the vibration direction, after entering the 1/4 lambda plate 6, when the incident polarized light forms a certain angle with the optical axis of the 1/4 lambda plate 6, the linearly polarized light can be changed into circularly polarized light and elliptically polarized light, the linearly polarized light, circularly polarized light and elliptically polarized light from the 1/4 lambda plate 6 can be incident on the target 7, and for carrying out different parameter detection on a camera, the target 7 can be a star plate target or an identification rate plate, wherein the star plate target is mainly applied to the point spread function detection aspect of the camera, and the identification rate plate is mainly applied to the aspects of the definition, the sensitivity, the signal-to-noise ratio, the non-uniformity detection and the like of the camera. The detection area of the discrimination plate is selected on the computer 11, and the specific algorithm is as follows:
1. the upper left horizontal position percentage refers to the position of the left side line of the detection area from left to right in the discrimination plate.
2. The upper left vertical position percentage refers to the position of the upper side line of the detection area from top to bottom of the discrimination plate.
3. The lower right horizontal position percentage refers to the position of the right side line of the detection area from left to right in the discrimination plate.
4. The lower right vertical position percentage refers to the position of the lower side line of the detection area from top to bottom of the discrimination plate.
The non-parallel light from the target 7 enters the focusing light inlet of the collimator 8, the non-parallel light is changed into parallel light beams through the internal concave-convex lens combination, and the parallel light beams enter the camera 9 on the multi-dimensional displacement table 10 after the non-parallel light is changed into parallel light beams through the collimator 8. The three-dimensional adjustment is realized by adjusting the horizontal front-back position, the horizontal left-right position and the horizontal height of the camera through the multi-dimensional displacement table 10, the camera 9 is connected with the computer 11 through a data connecting line, and imaging data of the camera are acquired by utilizing an image acquisition card in the computer.
The aviation socket on the power control module 12 is connected with the aviation plug on the halogen lamp mica wire, and the power supply is used for supplying power in an isolated mode, five modules are all used, so that the power supply is independent, the maintenance is convenient, and each group controls one halogen lamp switch and brightness. Considering electrical safety, the front panel of the power control module 12 comprises a status indication and a light intensity adjustment by adopting a low voltage (DC 12V) to control a high voltage (220V), the backboard is integrated to be inserted and arranged, and the external power supply adopts a standard aviation plug-in unit, so that the safety and convenience are realized.
The power supply control module 12 is powered on, the computer 11 is started, the monochromator 2 is started, the intensity of a light source in the integrating sphere A1 and the monochromator 2 are regulated, light rays can be received on the integrating sphere B3, the position of the collimator 8 is fixed, the emergent light of the collimator 8 is filled in the light incident surface of the camera 9, and the light incident surface of the camera 9 is parallel to the light emergent surface of the collimator 8 through the multi-dimensional displacement table 10.
In order to prove the applicability of the detection method of the invention, the detection method is described in detail by combining examples, and is characterized by comprising the following steps:
step one, initializing a camera and an optical path, opening an optical darkroom 13, removing a polarizer 4, a 1/2 lambda wave plate 5 and a 1/4 lambda wave plate 6, placing an identification rate plate as a target 7 in the optical path, closing the optical darkroom 13, and opening a monochromator 2.
And step two, adjusting and increasing the brightness value of the light source through the power control module 12, recording the brightness value at the moment through a strong light illuminometer on the integrating sphere B3 when the camera acquires the image gray value of the discrimination rate plate, converting the image data of the camera into a gray waveform chart, recording the brightness value at the moment when the camera reaches saturation, then starting to weaken the intensity value of the light source, recording the brightness value at the moment when 50% of the saturated brightness value is reached, then continuing to weaken the intensity value of the light source, recording the brightness value at the moment when 10% of the saturated brightness value is reached, then turning off the light source, and recording the brightness value at the moment under the condition of no illumination. The wavelength of the incident light is changed by the monochromator 2, then the camera records the illuminometer value at the moment when reaching saturation, then starts weakening the light source intensity value, records the illuminometer value at the moment when reaching 50% of the saturated illumination value, then continues weakening the light source intensity value, records the illuminometer value at the moment when reaching 10% of the saturated illumination value, then turns off the light source, records the illuminometer value at the moment under the condition of no illumination and collects the image data of the camera.
And thirdly, acquiring an image gray value of the camera when the incident light of the camera is 50% of the saturated illumination value, acquiring the image gray value of the camera when the incident light of the camera is 10% of the saturated illumination value, and acquiring the image gray value of the camera when the incident light of the camera is in a no-illumination condition. The image gradation value of the camera is collected when the camera incident light is 50% of the saturated light value after changing the wavelength of the light source with the monochromator 2, the image gradation value of the camera is collected when the camera incident light is 10% of the saturated light value, and the image gradation value of the camera is collected when the camera incident light is no light.
And fourthly, obtaining the signal-to-noise ratio of the camera by using the data recorded in the second step and the third step according to the formula 1, the formula 2 and the formula 3. And obtaining the non-uniformity of the light response of the camera by using the data recorded in the second step and the third step according to the formula 4, the formula 5, the formula 6, the formula 7 and the formula 8.
The camera Gray values Gray (m, n) are read in the absence of illumination and in the semi-saturated illumination, m representing the rows and n representing the columns. Calculated according to the following formula:
wherein the signal-to-noise ratio is equal to the average signal gray value F (G) under the half-saturated illumination condition signal Mean square error F (G) with gray value under no illumination noise Taking the base 10 logarithm and multiplying by a factor of 20.
The non-uniformity parameter of the camera is characterized by the value of the non-uniformity of the light response, M and N are the number of rows and columns of the image, a and b are the row index and the column index of the array respectively, and then the average digital signal value of the image of the Mth row and the Nth column under the condition of no illumination and fifty percent saturated illumination is y dark And y 50 Wherein μ is y,dark Sum mu y,50 Specific calculation methods are shown as formula (4) and formula (5) for average signal values under no illumination and fifty percent saturated illumination
S 2 y,dark And S is 2 y,50 The specific calculation method is as follows, equation (6) and equation (7):
wherein M and N are the number of rows and columns of the image, and a and b are the row index and the column index of the array, respectively;
the PRNU is a value of the optical response unevenness, and as shown in equation 8, the value of the camera unevenness parameter can be obtained by the optical response unevenness value corresponding to a single wavelength.
Further, the method for calculating the sensitivity of the camera comprises the following steps:
wherein mu y，10 Image average digital signal value under ten percent saturated illumination condition, E 10 And E is 50 An incident light intensity value of the camera under ten percent of saturated illumination condition and fifty percent of saturated illumination condition, S y，dark The root mean square value of the camera image under the condition of no incident light, V is the sensitivity value of the camera, E th Is the lowest illumination value of the camera.
The sensitivity value and the minimum sensitivity value of the camera are obtained by using the data recorded in the second step and the third step through the formulas 5, 9, 10, 11 and 12.
The image acquisition card software on the computer 11 is used for acquiring the image formed by the detection area of the discrimination plate under the condition that the incident light is 50 percent of saturated illumination, so that the discrimination plate forms a clear image of 100-800 line pairs on the imaging surface of the camera detector, and the maximum number of line pairs which can be resolved by the camera is recorded as the definition of the camera.
Step five, opening the optical darkroom 13, putting the polarizer 4, the 1/2 lambda wave plate 5 and the 1/4 lambda wave plate 6 into the optical path, putting the discrimination plate serving as the target 7 into the optical path, and closing the optical darkroom 13. The wavelength of the incident light is changed by the monochromator 2, the light source is changed into linear polarized light and circular polarized light by the polarizer 4, the 1/2 lambda plate 5 and the 1/4 lambda plate 6, then the illuminometer value at the moment is recorded when the camera reaches saturation, the intensity value of the light source is reduced, the illuminometer value at the moment is recorded when 50% of the saturated illumination value is reached, the intensity value of the light source is reduced continuously, the illuminometer value at the moment is recorded when 10% of the saturated illumination value is reached, the light source is turned off, the illuminometer value at the moment is recorded under the condition of no illumination and the image data of the camera are collected.
And then obtaining the sensitivity value and the minimum sensitivity value of the camera when the incident light is various polarized light by using the data recorded in the second step and the third step according to the formula 5, the formula 9, the formula 10, the formula 11 and the formula 12. And obtaining the signal to noise ratio of the camera when the incident light is various polarized light by using the data recorded in the second step and the third step according to the formula 1, the formula 2 and the formula 3. And obtaining the non-uniformity of the light response of the camera when the incident light is various polarized light by using the data recorded in the second step and the third step according to the formula 4, the formula 5, the formula 6, the formula 7 and the formula 8.
The embodiment of the present invention is explained to this end.
Claims (15)
1. A polarization spectrum camera detector, the detector comprising: the device comprises a light source generating module, a light source modulating module, a data acquisition and processing module, a power supply control module (12) and an optical darkroom (13);
wherein, the light source produces the module and includes: integrating sphere A (1), monochromator (2) and integrating sphere B (3), integrating sphere A (1), integrating sphere B (3) of monochromator (2) are connected sequentially, light source is installed outside integrating sphere A (1), and strong light illuminometer is installed on integrating sphere B (3);
the light source modulation module includes: the device comprises a polarizer (4), a 1/2 lambda wave plate (5), a 1/4 lambda wave plate (6), a target (7) and a collimator (8);
the data acquisition and processing module comprises: a camera (9), a multi-dimensional displacement table (10) and a computer (11);
the central axis of the light source generating module, the light source modulating module and the data acquiring and processing module is kept on a horizontal line, the power supply control module (12) is connected with the integrating sphere A (1), the optical darkroom (13) is of a shell structure, the left end of the optical darkroom is provided with the light inlet c, one end of the integrating sphere B (3) is connected with the light source modulating module through the light inlet c, and the light source modulating module and the data acquiring and processing module are arranged inside the shell structure of the optical darkroom (13).
2. The polarization spectrum camera detector according to claim 1, wherein the integrating sphere a (1) is provided with six openings, five of which are light source placing openings, one of which is a light outlet a, each light source placing opening is provided with 1 halogen lamp, each halogen lamp is provided with a cylindrical lampshade, and each lampshade is fixedly connected with the light source placing opening of the integrating sphere a (1).
3. A polarization spectrum camera detector according to claim 2, characterized in that the monochromator (2) is provided with an electrically powered filter wheel, a grating structure and a light exit slit.
4. A polarization spectrum camera detector according to claim 3, wherein the integrating sphere B (3) is provided with 4 openings, and the four openings comprise a light inlet B, a light outlet B, a detection opening for placing a strong light illuminometer probe, and a standby opening, wherein the standby opening and the light inlet B are vertically symmetrical on a hemispherical surface, and the detection opening of the strong light illuminometer probe is provided with the strong light illuminometer.
5. The polarization spectrum camera detector according to claim 4, wherein the light outlet a is connected with the electric filter wheel, the light outlet slit is connected with the light inlet B, the light outlet B enters the optical darkroom (13), the light enters the monochromator (2) from the light outlet a of the integrating sphere a (1) to become quasi-monochromatic light, enters the light inlet B of the integrating sphere B (3) to become uniform light, enters the polarizer (4) in the optical darkroom (13) from the light outlet B of the integrating sphere B (3) to become polarized light, and then enters the 1/2 lambda plate (5) to enter the 1/4 lambda plate (6) to form polarized light, circularly polarized light and elliptically polarized light to be incident on the target (7).
6. The polarization spectrum camera detector according to claim 5, wherein the light emitted after passing through the target (7) enters the collimator (8), and the light is converted into parallel light by the collimator (8) and then enters the camera (9) on the multi-dimensional displacement table (10).
7. The polarization spectrum camera detector according to claim 1, wherein the multi-dimensional displacement table (10) and the camera (9) are used for adjusting the horizontal front-back and horizontal left-right positions of the camera through the multi-dimensional displacement table (10), and the three-dimensional space position adjustment of the camera is realized through adjusting the horizontal height of the camera (9); the camera (9) is connected with the computer (11) through a data connecting wire.
8. A detection method applied to the polarization spectrum camera detector as claimed in claim 1, characterized in that the detection method comprises the following steps:
firstly, initializing a camera and an optical path, opening an optical darkroom (13), and removing a polarizer (4), a 1/2 lambda wave plate (5) and a 1/4 lambda wave plate (6);
modulating the intensity and wavelength of an incident light source of a camera;
step three, collecting image data;
step four, calculating quality parameters of the camera by utilizing an algorithm according to the image data acquired in the step three;
and fifthly, changing the polarization state of incident light, the intensity and the wavelength of a light source, opening an optical darkroom (13), putting a polarizer (4), a 1/2 lambda wave plate (5) and a 1/4 lambda wave plate (6), and repeating the third step and the fourth step to finish quality parameter detection of the camera in the polarized light state.
9. The method according to claim 8, wherein the initializing the setting in the first step specifically comprises: the power supply control module (12) is powered on, the computer (11) is started, the monochromator (2) is started, the intensity of a light source in the integrating sphere A (1) and the monochromator (2) are regulated, light rays can be received on the integrating sphere B (3), the position of the collimator (8) is fixed, the emergent light of the collimator (8) is filled with the light incident surface of the camera (9), and the light incident surface of the camera (9) is parallel to the light emergent surface of the collimator (8) through the multi-dimensional displacement table (10).
10. The detection method of a polarization spectrum camera detector according to claim 8, wherein the specific method for modulating the intensity and wavelength of the incident light source of the camera in the second step is as follows: the light source brightness starts to increase until the camera incident light reaches a half-saturated condition, and a wavelength-light source intensity graph is acquired.
11. The method according to claim 8, wherein the quality parameters in the fourth step include: camera sensitivity, camera sharpness, camera signal-to-noise ratio, and camera non-uniformity.
12. The method for detecting a polarization spectrum camera according to claim 11, wherein the signal-to-noise ratio of the camera is calculated by:
the camera Gray values Gray (m, n) are read in the absence of illumination and in the semi-saturated illumination, m representing the row and n representing the column, calculated according to the following formula:
wherein the signal-to-noise ratio is equal to the average signal gray value F (G) under the half-saturated illumination condition signal Mean square error F (G) with gray value under no illumination noise Taking the base 10 logarithm and multiplying by a factor of 20.
13. The method for detecting the polarization spectrum camera according to claim 11, wherein the method for calculating the non-uniformity of the camera comprises:
the camera non-uniformity parameter is characterized by the values of dark signal non-uniformity and light response non-uniformity,
let M, N be the number of rows and columns of the image, a and b be the row index and column index of the array, respectively, then the average digital signal value of the image under no illumination and fifty percent saturated illumination of the Mth row, N column is y dark And y 50 Wherein μ is y，dark Sum mu y，50 Specific calculation methods such as formula (4) and formula (5) are specific to the average dark signal value under no illumination condition and fifty percent saturated illumination condition
S 2 y,dark And S is 2 y,50 The specific calculation method is as follows, equation (6) and equation (7):
wherein M and N are the number of rows and columns of the image, and a and b are the row index and the column index of the array, respectively;
the PRNU is a value of the optical response unevenness as shown in equation (8), and the value of the camera unevenness parameter can be obtained by the optical response unevenness value corresponding to a single wavelength.
14. The method for detecting a polarization spectrum camera according to claim 11, wherein the method for calculating the sensitivity of the camera is as follows:
wherein mu y，10 Image average digital signal value under ten percent saturated illumination condition, E 10 And E is 50 An incident light intensity value of the camera under ten percent of saturated illumination condition and fifty percent of saturated illumination condition, S y,dark The root mean square value of the camera image under the condition of no incident light, V is the sensitivity value of the camera, E th Is the lowest illumination value of the camera.
15. The method according to claim 8, wherein the specific method for changing the polarization state and the light source intensity and the wavelength of the incident light in the fifth step is to modulate the light incident on the camera into linear polarized light, circular polarized light and elliptical polarized light, and modulate the light source intensity of the incident light on the camera under the condition.
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