CN108680251B - Subdivision spectrum scanning calibration device based on super continuous laser and monochromator - Google Patents

Abstract

The invention discloses a subdivision spectrum scanning calibration device based on supercontinuous laser and monochromator. The monochromator is tuned to output monochromatic light. After collimation, focusing and beam splitting, a part of the light energy is reflected on the surface of the beam splitter and then enters the laser wavelength meter to realize real-time monitoring of the output wavelength and bandwidth. The remainder passes through the beam splitter into the decoherent integrating sphere, producing a uniform monochromatic surface light source. The absolute spectral radiance of the integrating sphere is obtained by the standard radiance detector traced to the low temperature absolute radiometer. The standard radiance detector and the equipment to be calibrated are alternately measured by the linear displacement stage, and the monochromator is tuned to output the monochromatic colors of different wavelengths in turn. light, and then realize the spectral subdivision scanning calibration of the equipment to be calibrated. The invention has wide application prospects in optical radiation measurement and high-precision calibration of remote sensors.

Description

A Subdivision Spectral Scanning Calibration Device Based on Supercontinuum Laser and Monochromator

technical field

The invention relates to the technical field of optical radiation measurement and remote sensor calibration, in particular to a subdivision spectrum scanning calibration device based on a supercontinuum laser and a monochromator.

Background technique

Traceable from the low temperature absolute radiometer, the radiation transfer link based on the standard detector is a high-precision radiation calibration technology link recognized by the industry at this stage. The absolute spectral power responsivity of the standard transfer detector can be obtained by using a low-temperature absolute radiometer, and the spectral radiance responsivity can be obtained from the spectral power responsivity by using the radiance geometric conversion structure (such as the Gershun tube form), so as to realize the traceability of the spectral radiance to the highest level. Precision Optical Power Primary Reference.

The low-temperature absolute radiometer is recognized as the most accurate optical power radiation reference in the industry, but when using the low-temperature absolute radiometer to transmit spectral radiation information, it is necessary to use monochromatic light radiation as the excitation light source. In earth observation remote sensing, most of the radiation values observed by remote sensors are spectral radiance information, which requires that the test light source should be a uniform radiance surface light source (for example, integrating spherical light source).

At present, there are two main methods that can provide monochromatic light tunable output: dispersion technology based on monochromator and tunable laser technology. Generally speaking, the monochromator systems used in radiometric calibration are mostly double monochromators, which have higher monochromatic light purity and lower stray light level, which is more conducive to improving the accuracy level of calibration. At present, the monochromator system used for radiometric calibration mainly uses halogen tungsten lamps as light sources. The power level of halogen tungsten lamps is low, and the efficiency of the monochromator system itself is low, so that the monochromator system can only be applied to the spectrum of the remote sensor. Calibration and calibration of relative spectral (power) responsivity cannot be applied to the calibration of absolute spectral radiance responsivity of remote sensors. The tunable laser has the characteristics of high optical power level and good monochromaticity. The laser is introduced into the integrating sphere to generate a uniform monochromatic surface light source, which can realize the system-level calibration of the spectral radiance responsivity of the remote sensor. The monochromaticity is also suitable for high-precision spectral calibration of remote sensors. At present, many metrology departments at home and abroad have established radiation calibration standard light source systems based on tunable lasers, such as the National Institute of Standards and Technology (NIST), the German Institute of Technical Physics (PTB) and the Anhui Institute of Optics and Fine Mechanics (AIOFM), Chinese Academy of Sciences. )Wait.

When using monochromatic light for radiative transfer and calibration, it is necessary to scan the channel of the remote sensor to traverse all the working bands of the remote sensor. The monochromator technology is mature and easy to program-controlled operation, and it is very suitable for spectral subdivision scanning, but currently it can only be used for spectral calibration and relative spectral responsivity calibration of remote sensors; the wavelength tuning of current tunable lasers relies more on For professional operators, the degree of automation is not high. If spectral subdivision scanning is performed, it takes a lot of time and the calibration period is long. The cost of tunable lasers is high, especially to establish full laser coverage that completely covers the solar reflection band, which requires multiple laser combinations to achieve, and also needs to be equipped with necessary auxiliary equipment such as wavelength meters, power meters, beam quality analyzers, and stable laser power. device, etc. A comprehensive assessment requires millions, or even tens of millions, of capital investment. In addition, the operation of the laser has higher requirements on the environment, such as cleanliness, indoor temperature and humidity, etc. The operation and maintenance of the laser also require professionals. These objective factors lead to the fact that the tunable laser-based spectral scanning calibration technology is mainly concentrated in professional and powerful metrology laboratories, which is not conducive to the popularization and application of this high-precision calibration technology.

SUMMARY OF THE INVENTION

The purpose of the present invention is to make up for the defects of the prior art, and to provide a subdivision spectrum scanning calibration device based on a supercontinuum laser and a monochromator.

The present invention is achieved through the following technical solutions:

A subdivision spectrum scanning calibration device based on supercontinuum laser and monochromator, including supercontinuum laser light source, slit coupling optical path, monochromator, monochromator output collimator, focusing lens, beam splitter, Laser wavelength meter, decoherent integrating sphere, electronically controlled translation stage, standard radiance detector and equipment to be calibrated, the supercontinuum laser light source outputs broadband laser light through its collimator, and the beam is coupled to the monochromator after passing through the slit coupling optical path In the entrance slit of the monochromator, after the monochromator is tuned, monochromatic light is output from the exit slit of the monochromator, and the exit slit of the monochromator is located at the effective focus of the output collimating mirror of the monochromator. After the output collimating lens is collimated, the collimated beam is output. After the collimated beam passes through the focusing lens, the beam is focused again. The focused beam passes through the beam splitter at the back end of the optical path, and its surface reflects part of the beam, and this part of the reflected beam is focused to the laser. On the incident fiber end face of the wavelength meter, the laser wavelength meter interprets the wavelength and bandwidth output by the current monochromator in real time; the other part of the beam focused by the focusing lens passes through the beam splitter and enters the decoherent integrating sphere through the light entrance of the decoherent integrating sphere The decoherent integrating sphere is provided with a rotating diffuse reflection plate, a baffle plate and a monitoring detector. The light entering the decoherent integrating sphere falls on the rotating diffuse reflection plate, and the baffle prevents the rotation of the diffuse reflection plate. The primary reflected light is directly emitted from the light outlet of the decoherent integrating sphere. After multiple reflections and uniform light inside the decoherent integrating sphere, it exits from the light outlet of the decoherent integrating sphere. The monitoring detector monitors the stability of the light source of the decoherent integrating sphere in real time. , and feedback and fine-tune the output power of the supercontinuum laser according to the change of the radiance in the decoherent integrating sphere. The standard radiance detector and the equipment to be calibrated are installed on the electronically controlled translation stage, and the electronically controlled translation stage is moved and switched. Direct the light entrance of the standard radiance detector and the equipment to be calibrated to the light exit of the decoherent integrating sphere, respectively. The standard radiance detector measures the reference spectral radiance of the light exit of the decoherent integrating sphere. The measurement results are compared to realize the alternative radiation calibration based on the standard detector.

The working band of the supercontinuous laser light source covers 400-2400 nm.

The slit coupling optical route is composed of three off-axis parabolic mirrors, namely off-axis parabolic mirror 1, off-axis parabolic mirror 2 and off-axis parabolic mirror 3. The supercontinuous laser beam passes through the off-axis parabolic mirror. After 1, focusing occurs, and the focus is located at the focal point of the off-axis parabolic mirror 2, so the beam is collimated again after passing through the off-axis parabolic mirror 2. The focal length of the off-axis parabolic mirror 2 is m times that of the off-axis parabolic mirror 1. , so the off-axis parabolic mirror 1 and the off-axis parabolic mirror 2 constitute a reflective Kepler laser beam expander. The beam diameter after the off-axis parabolic mirror 2 is m*D, where D is the supercontinuum laser. The light source outputs the diameter of the broadband laser through its collimator. The off-axis parabolic mirror 3 focuses the beam after passing through the off-axis parabolic mirror 2 again. The focus is located at the entrance slit of the monochromator, and the off-axis parabolic mirror is set. The effective focal length of the third is f ₃ , then the relative aperture of the focused beam is f ₃ /(mD), and the relative aperture of the monochromator is FNUM_mono, if f ₃ /(mD)=FNUM_mono, then the supercontinuum laser is The best match is coupled into the monochromator.

The slit of the monochromator is adjustable, the built-in gratings are all blazed gratings, and the grating combination is suitable for the working band of 400-2400nm. Pure output of narrow-band spectrum at any wavelength in the 2400nm range.

The laser wavelength meter is an echelle spectrometer type laser wavelength meter, and the working band range covers 400nm~1100nm, which is used to monitor the output wavelength and bandwidth of the monochromator; the beam input mode of the laser wavelength meter is fiber coupling input, which can be real-time Measure the wavelength and bandwidth information; the laser wavelength meter is placed behind the reflection surface of the beam splitter, and receives the monochromator output focused by the focusing lens and reflected on the surface of the beam splitter. If the output wavelength of the monochromator exceeds the working band range of the laser wavelength meter, adjust the filter wheel of the monochromator to the channel without filter, and use the laser wavelength meter to measure the high diffraction order spectrum of the monochromator system to determine output wavelength.

The inner layer of the decoherent integrating sphere is made of polytetrafluoroethylene material, and has a light entrance port, a light exit port, a monitoring detector installation port and a rotating diffuse reflection plate installation port. on the wall of the mouth. A built-in baffle coated with Teflon coating is installed on the spherical wall between the rotating diffuse reflector and the light outlet of the integrating sphere to prevent the primary reflected light of the rotating diffuse reflector from directly exiting from the integrating sphere port. The quasi-monochromatic light emitted from the monochromator is focused by the focusing lens and split by the beam splitter, and the light spot falls on the central area of the rotating diffuse reflector. Under the action of the rotating diffuse reflector and the high reflectivity diffusing coating on the inner wall of the integrating sphere, the incident light is fully homogenized, and a uniform radiance surface light source is formed at the mouth of the integrating sphere. The monitoring detector is installed on the spherical wall near the light outlet of the integrating sphere, directly monitors the change of the radiance on the inner wall of the integrating sphere, and feeds back and fine-tunes the output power of the supercontinuum laser according to the change of the radiance in the integrating sphere to ensure the output of the supercontinuum laser. stability. The installation position of the monitoring detector should prevent the monitoring detector from directly observing the light entrance of the integrating sphere, the rotating diffuse reflector and the built-in baffle.

The rotating diffuse reflection plate is composed of a diffuse reflection plate and a DC motor. The diffuse reflection plate is fixed on the rotating shaft of the DC motor and rotates around the rotating shaft as the motor rotates. The surface coating material of the diffuse reflector is polytetrafluoroethylene, the diffuse reflector faces the interior of the integrating sphere, and the reflector is flush with the inner wall of the integrating sphere.

The standard radiance detectors include three types: silicon standard radiance detectors, indium gallium arsenic standard radiance detectors and extended indium gallium arsenic standard radiance detectors, and the three standard radiance detectors jointly cover 400- 2400nm working band; the absolute radiation values of the three standard radiance detectors are all traceable to the low temperature absolute radiometer. During the standard transfer process, select the corresponding standard radiance detector or standard radiance detector according to the working band of the equipment to be calibrated device combination.

The electronically controlled translation stage is an electronically controlled linear displacement translation stage, which is used to realize the alternate measurement of the standard radiance detector and the instrument to be calibrated.

The supercontinuum laser light source, laser wavelength meter, monitoring detector, standard radiance detector and equipment to be calibrated are all controlled by a control computer.

If the entrance pupil of the device to be calibrated exceeds the size of the light outlet of the decoherent integrating sphere, place an off-axis parabolic mirror 4 behind the light outlet of the decoherent integrating sphere, and the effective focus of the off-axis off-axis parabolic mirror 4 is at At the light exit of the decoherent integrating sphere, as long as the beam divergence angle collimated by the off-axis parabolic mirror 4 is not less than the field of view of the device to be calibrated, the effective aperture of the off-axis parabolic mirror 4 is not less than the entrance pupil of the device to be calibrated The matching of the field of view and the aperture between the light source and the device to be calibrated can be achieved. The beams collimated by the four off-axis parabolic mirrors face the standard radiance detector located on the electronically controlled translation stage and the calibration device to be calibrated respectively. The light entrance of the device.

The monochromator output collimating mirror is an off-axis parabolic mirror, and its focal position is located at the monochromator exit slit, and its function is to make the output monochromatic light of the monochromator collimated and output.

The focusing lens focuses the collimated beam collimated and output by the monochromator into a small light spot, which is convenient for the reception of the subsequent optical path.

The beam splitter realizes that the output beam of the monochromator is split according to the intensity, and a small amount of light energy is reflected by the surface of the beam splitter and then received by the laser wavelength meter. Most of the light energy passes through the beam splitter and enters the decoherent integrating sphere.

The advantages of the present invention are: the present invention adopts the supercontinuum laser as the illumination light source of the monochromator, realizes the great improvement of the output monochromatic light intensity of the traditional monochromator system, and makes the monochromator system suitable for the absolute spectrum of the remote sensor. The calibration of the radiance responsivity expands the application range of the monochromator system in radiometric measurement and remote sensor radiometric calibration. With the flexible control feature of the monochromator system, the convenience of spectral scanning calibration in radiometric calibration is greatly improved, and the cycle of spectral calibration and radiometric calibration of remote sensors can be effectively reduced. In the present invention, it is proposed that the output wavelength and bandwidth of the monochromator can be traced to a high-precision laser wavelength meter. Compared with the traditional monochromator calibration method based on spectral line lamps and single-point lasers, the laser wavelength meter can effectively increase the monochromatic color. The wavelength detection point of the instrument calibration can even monitor the output wavelength and bandwidth of the monochromator system in real time, which can effectively improve the calibration accuracy of the monochromator, thereby effectively improving the accuracy level of the remote sensor laboratory calibration.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

FIG. 2 is a structural diagram after adding four off-axis parabolic mirrors.

Detailed ways

As shown in Figure 1, a subdivision spectral scanning calibration device based on supercontinuum laser and monochromator, including supercontinuum laser light source 1, slit coupling optical path 2, monochromator 3, and monochromator output collimation Mirror 4, focusing lens 5, beam splitter 6, laser wavelength meter 7, decoherent integrating sphere 8, electronically controlled translation stage 10, standard radiance detector 9 and equipment to be calibrated 11, through which the supercontinuum laser light source 1 is collimated The device outputs broadband laser light. The beam is coupled to the entrance slit of the monochromator 3 after passing through the slit coupling optical path 2. After tuning by the monochromator 3, the output slit of the monochromator 3 outputs monochromatic light. The exit slit of the instrument 3 is located at the effective focus of the output collimating mirror 4 of the monochromator. After being collimated by the output collimating mirror 4 of the monochromator, a collimated beam is output. After the collimated beam passes through the focusing lens 5, the beam is focused again. , the focused beam passes through the beam splitter 6 at the rear end of the optical path, and its surface reflects a part of the beam, and this part of the reflected beam is focused on the incident fiber end face of the laser wavelength meter 7, and the laser wavelength meter 7 interprets the wavelength output by the current monochromator 3 in real time. and bandwidth; another part of the light beam focused by the focusing lens 5 passes through the beam splitter 6 and enters the decoherence integrating sphere 8 through the light entrance 81 of the decoherence integrating sphere 8. The decoherence integrating sphere 8 is provided with a rotating diffuser. The reflection plate 82, the baffle 83 and the monitoring detector 84, the light entering the decoherent integrating sphere 8 falls on the rotating diffuse reflection plate 82, and the baffle 83 prevents the primary reflected light of the rotating diffuse reflection plate 82 from directly decohering from the decoherence plate 83. The light exit 85 of the integrating sphere 8 exits, and after multiple reflections and homogenization inside the decoherent integrating sphere 8, it exits from the light exit 85 of the decoherent integrating sphere 8, and the monitoring detector 84 monitors the stability of the light source of the decoherent integrating sphere 8 in real time. , and according to the change of the radiance in the decoherent integrating sphere 8, feedback and fine-tune the output power of the supercontinuum laser, the standard radiance detector 9 and the equipment to be calibrated 11 are installed on the electronically controlled translation stage 10, and the electronically controlled translation The stage 10 is moved and switched, and the light entrances of the standard radiance detector 9 and the equipment to be calibrated 11 are respectively aligned with the light output port 85 of the decoherent integrating sphere 8. The standard radiance detector 9 measures the light output of the decoherent integrating sphere 85. The reference spectral radiance is compared with the measurement result of the device 11 to be calibrated, so as to realize the alternative radiation calibration based on the standard detector.

The working wavelength band of the supercontinuous laser light source 1 covers 400-2400 nm.

The slit coupling optical path 2 is composed of three off-axis parabolic mirrors, namely off-axis parabolic mirror one 21, off-axis parabolic mirror two 22 and off-axis parabolic mirror three 23. After the first off-axis parabolic mirror 21, focusing occurs, and the focal point is located at the focal point of the off-axis parabolic mirror 2 22, so the beam is collimated again after passing through the off-axis parabolic mirror 2 22, and the focal length of the off-axis parabolic mirror 2 22 is The off-axis parabolic mirror 1 is m times larger than the off-axis parabolic mirror 1, so the off-axis parabolic mirror 1 21 and the off-axis parabolic mirror 2 22 form a reflective Kepler laser beam expander. The beam diameter after the off-axis parabolic mirror 2 22 is m*D, where D is the diameter of the broadband laser output from the supercontinuum laser light source through its collimator. The off-axis parabolic mirror 3 23 focuses the beam after the off-axis parabolic mirror 2 22 again, and the focus is on the monochromatic At the entrance slit of the instrument 3, set the effective focal length of the off-axis parabolic mirror 3 23 to be f ₃ , then the relative aperture of the beam after being focused is f ₃ /(mD), and the relative aperture of the monochromator 3 is set to be FNUM_mono , if f ₃ /(mD) = FNUM_mono, the supercontinuum laser is optimally coupled into the monochromator 3 .

The slit of the monochromator 3 is adjustable, the built-in gratings are all blazed gratings, and the grating combination is suitable for the working band of 400-2400nm. Pure output of narrow-band spectrum at any wavelength in the range of 400-2400nm.

The laser wavelength meter 7 is a laser wavelength meter of the echelle spectrometer type, and the working band range covers 400 nm to 1100 nm, and is used to monitor the output wavelength and bandwidth of the monochromator; the beam input mode of the laser wavelength meter 7 is fiber coupling input, The wavelength and bandwidth information can be measured in real time; the laser wavelength meter is placed behind the reflection surface of the beam splitter to receive the monochromator output focused by the focusing lens and reflected by the surface of the beam splitter. If the output wavelength of the monochromator exceeds the working band range of the laser wavelength meter, adjust the filter wheel of the monochromator to the channel without filter, and use the laser wavelength meter to measure the high diffraction order spectrum of the monochromator system to determine output wavelength.

The inner layer of the decoherent integrating sphere 8 is made of polytetrafluoroethylene material, and has a light entrance port, a light exit port, a monitoring detector installation port and a rotating diffuse reflection plate installation port. on the wall of the light mouth. A built-in baffle 83 sprayed with Teflon coating is installed on the spherical wall between the rotating diffuse reflector 82 and the integrating sphere light outlet 85 to prevent the primary reflected light of the rotating diffuse reflector 82 from directly exiting from the integrating sphere opening. The quasi-monochromatic light emitted from the monochromator is focused by the focusing lens 5 and split by the beam splitter 6, and the light spot falls on the central area of the rotating diffuse reflection plate 82. Under the action of the rotating diffuse reflection plate 82, the elimination of the laser light is realized. coherent. Under the action of the rotating diffuse reflector 82 and the high-reflection diffusing coating on the inner wall of the integrating sphere, the incident light is fully homogenized, and a uniform radiance surface light source is formed at the mouth of the integrating sphere. The monitoring detector 84 is installed on the spherical wall near the light outlet of the integrating sphere, directly monitors the change of the radiance of the inner wall of the integrating sphere, and feeds back and fine-tunes the output power of the supercontinuum laser according to the change of the radiance in the integrating sphere to ensure the supercontinuum laser output stability. The installation position of the monitoring detector should prevent the monitoring detector from directly observing the light entrance 81 of the integrating sphere, the rotating diffuse reflection plate 82 and the built-in baffle 83 .

The rotating diffuse reflection plate 82 is composed of a diffuse reflection plate and a DC motor. The diffuse reflection plate is fixed on the rotating shaft of the DC motor, and rotates around the rotating shaft as the motor rotates. The surface coating material of the diffuse reflector is polytetrafluoroethylene, the diffuse reflector faces the interior of the integrating sphere, and the reflector is flush with the inner wall of the integrating sphere.

The standard radiance detector 9 includes three types: silicon standard radiance detector, indium gallium arsenide standard radiance detector and extended indium gallium arsenide standard radiance detector, and the three standard radiance detectors jointly cover 400 -2400nm working band; the absolute radiation values of the three standard radiance detectors are all traceable to the low temperature absolute radiometer. During the standard transfer process, the corresponding standard radiance detector or standard radiance is selected according to the working band of the equipment to be calibrated detector combination.

The electronically controlled translation stage 10 is an electronically controlled linear displacement translation stage, which is used to realize the alternate measurement of the standard radiance detector and the to-be-calibrated instrument.

The supercontinuum laser light source 1 , the laser wavelength meter 7 , the monitoring detector 84 , the standard radiance detector 9 and the equipment to be calibrated 11 are all controlled by the control computer 12 .

If the entrance pupil of the device to be calibrated exceeds the size of the light exit port 85 of the integrating sphere 8, another solution can be adopted. Referring to FIG. 2 , an off-axis parabolic mirror 13 is placed at the rear end of the light outlet 85 of the integrating sphere 8 , and the effective focus of the off-axis off-axis parabolic mirror 13 is just at the light outlet 85 of the integrating sphere 8 . The beam emitted by the mirror 13 is a collimated beam with a certain divergence angle, which is used to simulate an infinite target. In this solution, by selecting the appropriate focal length and aperture of the off-axis parabolic mirror 13, and ensuring that the light exit 85 of the integrating sphere 8 is located at the effective focus of the off-axis parabolic mirror 13, as long as the parabolic mirror 13 is collimated The beam divergence angle is not less than the field of view of the device to be calibrated 11, and the effective aperture of the off-axis parabolic mirror 13 is not less than the size of the entrance pupil of the device to be calibrated 11. Field matching and aperture matching. The standard radiance detector 9 and the device to be calibrated 11 are installed on the linear displacement stage 10, and the linear displacement stage 10 is moved and switched. The light entrances of the standard radiance detector 9 and the device to be calibrated 11 face each other and are reflected by off-axis paraboloids. The beam collimated by the mirror 13, the monitoring detector 84 monitors the stability of the integrating sphere light source in real time. The standard radiance detector 9 measures the reference spectral radiance of the light outlet 85 of the integrating sphere 8, and compares it with the measurement result of the device to be calibrated 11 to realize the alternative radiation calibration based on the standard detector. Control the monochromator 3 to tune the output wavelength and use the laser wavelength meter 7 to measure the output wavelength of the monochromator 3 in real time. The beam monitoring detector 84 monitors the stability of the integrating sphere light source in real time, and feeds back and fine-tunes the output power of the supercontinuum laser according to the change of the radiance in the integrating sphere to ensure the stability of the supercontinuum laser output. The device to be calibrated 11 collects data and performs spectral calibration of the device to be calibrated after data processing. In this solution, the supercontinuum laser light source 1 , the laser wavelength meter 7 , the monitoring detector 84 , the standard radiance detector 9 and the equipment to be calibrated 11 are all controlled by the control computer 12 .

Claims (10)

1. A subdivision spectrum scanning calibration device based on a supercontinuum laser and a monochromator is characterized in that: the device comprises a super-continuous laser light source, a slit coupling light path, a monochromator output collimator, a focusing lens, a beam splitter, a laser wavelength meter, a decoherence integrating sphere, an electric control translation stage, a standard radiance detector and a device to be calibrated, wherein the super-continuous laser light source outputs broadband laser through the collimator of the super-continuous laser light source, a light beam is coupled into an incident slit of the monochromator after passing through the slit coupling light path and is tuned by the monochromator to output monochromatic light in an emergent slit of the monochromator, the emergent slit of the monochromator is positioned at an effective focus of the monochromator output collimator and is collimated by the monochromator output collimator to output a collimated light beam, the light beam is focused again after passing through the focusing lens, the focused light beam passes through the beam splitter at the rear end of the light path, the surface of the focused light beam reflects a part of the light beam, and the part of the reflected, the laser wavelength meter judges the wavelength and the bandwidth output by the current monochromator in real time; the other part of the light beam focused by the focusing lens penetrates through the beam splitter, enters the incoherent integrating sphere through a light inlet of the incoherent integrating sphere, a rotary diffuse reflection plate, a baffle and a monitoring detector are arranged in the incoherent integrating sphere, the light entering the incoherent integrating sphere falls on the rotary diffuse reflection plate, the baffle prevents primary reflected light of the rotary diffuse reflection plate from directly emitting from a light outlet of the incoherent integrating sphere, the uniform light is reflected for multiple times in the incoherent integrating sphere and then emitted from the light outlet of the incoherent integrating sphere, the monitoring detector monitors the stability of a light source of the incoherent integrating sphere in real time, the output power of the supercontinuum laser is fed back and finely adjusted according to the change of radiance in the incoherent integrating sphere, the standard radiance detector and the equipment to be calibrated are arranged on an electric control translation table, the light inlets of the standard radiance detector and the equipment to be calibrated are respectively opposite to the light outlet of the incoherent integrating sphere through the electric control translation table for moving and switching, and the standard radiance detector measures the reference spectrum radiance of the light outlet of the decoherence integrating sphere, and the reference spectrum radiance is compared with the measurement result of equipment to be calibrated to realize the alternative radiometric calibration based on the standard detector.

2. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the working waveband of the super-continuous laser light source covers 400-2400 nm.

3. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the slit coupling light path consists of three off-axis parabolic reflectors, namely a first off-axis parabolic reflector, a second off-axis parabolic reflector and a third off-axis parabolic reflector, after passing through the first off-axis parabolic reflector, the super-continuous laser beam is focused, the focus is located at the focus of the second off-axis parabolic reflector, so that the beam is collimated again after passing through the second off-axis parabolic reflector, the focal length of the second off-axis parabolic reflector is m times of that of the first off-axis parabolic reflector, so that the first off-axis parabolic reflector and the second off-axis parabolic reflector form a reflective Kepler type laser beam expander, the diameter of the beam after passing through the second off-axis parabolic reflector is m x D, wherein D is the diameter of the wide-waveband laser output by the collimator of the super-continuous laser source, and the third off-axis parabolic reflector is used for focusing again the beam after passing through the second off-axis parabolic reflector, the focal point is positioned at the entrance slit of the monochromator, and the effective focal length of the off-axis parabolic reflector III is set as f₃The relative aperture of the beam after focusing is f₃V (mD), let the relative aperture of the monochromator be FNUM _ mono, if f₃/(mD) = FNUM mono, the supercontinuum laser is coupled into the monochromator with the best match.

4. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the slit of the monochromator is adjustable, the built-in gratings are all blazed gratings, the grating combination is suitable for 400-2400nm working wave band, and a graded-order optical filter rotating wheel is arranged in the monochromator.

5. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 4, characterized in that: the laser wavelength meter is a laser wavelength meter of an echelle grating spectrometer type, the working waveband range covers 400 nm-1100 nm, and the laser wavelength meter is used for monitoring the output wavelength and the bandwidth of a monochromator; the laser wavelength meter adopts a light beam input mode of optical fiber coupling input, and measures wavelength and bandwidth information in real time; the laser wavelength meter is arranged behind the reflecting surface of the beam splitter and receives the output of the monochromator focused by the focusing lens and reflected by the surface of the beam splitter, if the output wavelength of the monochromator exceeds the working waveband range of the laser wavelength meter, the extinction order filter rotating wheel of the monochromator is adjusted to a channel without the filter, the laser wavelength meter is used for measuring the high diffraction order spectrum of the monochromator, and the output wavelength is determined.

6. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 5, characterized in that: the decoherence integrating sphere inner container coating is made of polytetrafluoroethylene materials and is provided with a light inlet, a light outlet, a monitoring detector mounting port and a rotating diffuse reflection plate mounting port, the monitoring detector and the rotating diffuse reflection plate are respectively mounted on the monitoring detector mounting port and the rotating diffuse reflection plate mounting port, the rotating diffuse reflection plate mounting port is positioned on the sphere wall opposite to the light inlet, the baffle is mounted on the sphere wall between the rotating diffuse reflection plate and the decoherence integrating sphere light outlet, the polytetrafluoroethylene coating is sprayed on the baffle, the monitoring detector is positioned on the sphere wall near the integrating sphere light outlet and avoids directly observing the integrating sphere light inlet, the rotating diffuse reflection plate and the baffle, the rotating diffuse reflection plate is composed of the diffuse reflection plate and a direct current motor, the diffuse reflection plate is fixed on the rotating shaft of the direct current motor and rotates around the rotating shaft as the center, the coating on the surface of the diffuse reflection plate is made of polytetrafluoroethylene materials, the diffuse reflection surface faces the interior of the integrating sphere, and the reflection surface is flush with the inner wall of the integrating sphere.

7. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the standard radiance detector comprises three types of a silicon standard radiance detector, an indium gallium arsenic standard radiance detector and an expanded indium gallium arsenic standard radiance detector, and the three types of standard radiance detectors jointly cover 400-2400nm working wave bands; the absolute radiation values of the three standard radiance detectors are traced to the low-temperature absolute radiometer, and in the standard transmission process, the corresponding standard radiance detector or the standard radiance detector combination is selected according to the working waveband of the equipment to be calibrated.

8. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the electric control translation stage is an electric control linear displacement translation stage and is used for realizing the alternate measurement of the standard radiance detector and the instrument to be calibrated.

9. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: the supercontinuum laser light source, the laser wavelength meter, the monitoring detector, the standard radiance detector and the equipment to be calibrated are all controlled by a control computer.

10. The subdivision spectrum scanning calibration device based on the supercontinuum laser and the monochromator as claimed in claim 1, characterized in that: if the entrance pupil of the device to be calibrated exceeds the size of the light outlet of the decoherence integrating sphere, a fourth off-axis parabolic reflector is arranged at the rear end of the light outlet of the decoherence integrating sphere, the effective focus of the fourth off-axis parabolic reflector is positioned at the light outlet of the decoherence integrating sphere, as long as the divergence angle of the light beam collimated by the fourth off-axis parabolic reflector is not smaller than the field angle of the device to be calibrated, and the effective caliber of the fourth off-axis parabolic reflector is not smaller than the size of the entrance pupil of the device to be calibrated, the field-of-view matching and the aperture matching between the light source and the device to be calibrated can be realized, and the light beam collimated by the fourth off-axis parabolic reflector respectively faces the standard radiance detector positioned on the electric control translation stage and the light inlet of the device.

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