CN113108907A - Ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity - Google Patents
Ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity Download PDFInfo
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Abstract
The invention relates to an ultraviolet spectrum imager, in particular to a high-sensitivity and high-dynamic ultraviolet spectrum imager. The invention aims to solve the technical problems of lower luminous flux, poor signal-to-noise ratio and lower sensitivity of the existing ultraviolet spectrum imager and provides the ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity. The imager adopts a Hadamard template to complete spatial light path gating, a specific dispersion system and an ultraviolet sensitive image enhancement type detector assembly, utilizes a combined signal measurement mode to reduce the influence of inherent errors of the ultraviolet spectrum imager on a true value of a target signal, indirectly reduces the deviation of a measured value and the true value of the target signal, improves the signal-to-noise ratio of a detection signal, and improves luminous flux due to the adoption of the Hadamard template, so that the ultraviolet spectrum imager integrally meets high sensitivity.
Description
Technical Field
The invention relates to an ultraviolet spectrum imager, in particular to a high-sensitivity and high-dynamic ultraviolet spectrum imager.
Background
The spectral imaging technology starts in the 80 th 20 th century, can obtain a two-dimensional geometric image and spectral dimensional information of a target and provide a mapping relation between the two, is widely applied and paid attention to fields requiring spatial position and spectral fingerprint information of the target, such as environmental resource detection, astronomical observation, space weather research, biomedicine and other fields, and has the advantage that common telescopes, radars and other remote sensing technologies cannot replace the technologies.
The spectral imaging instrument mainly comprises an interference spectral imaging instrument and a dispersion spectral imaging instrument. The interference type spectral imager can obtain higher luminous flux and signal-to-noise ratio than the traditional dispersion type spectral imager by utilizing the advantages of an optical multiplexing technology, and is successfully applied to visible and infrared spectral bands at present. However, the system structure and the inversion algorithm are complex, the requirement on the structural stability of the assembly is high, when the observation spectrum is expanded to ultraviolet or even shorter wavelength, the requirement on the assembly precision of the optical element, the structural assembly and the system is greatly improved, and the existing processing and assembling level in the industry is difficult to meet the requirement. The dispersive spectral imager has the advantages of simple structure, high stability, linear reading of spectral data and the like, and becomes a more ideal ultraviolet spectrum detection technical approach internationally acknowledged in the last two decades. At present, a series of satellites which are loaded with spectrometers and successfully emit light are all dispersive type spectrum IMAGERs, such as AIRS, GUVI, SSUI, hiras, RAIDS, and IMAGER which are loaded in sequence. However, since a common dispersive spectrometer inevitably needs to use a slit (slit) mechanism to constrain the spatial light, a large optical energy loss is caused while spectrum aliasing (spectral overlapping) of a spectrum imaging surface is reduced, and complete information of a target can be obtained only by completing push-scanning in a slit orthogonal direction, so that a time resolution is low.
Ultraviolet spectral detection covers four intervals, near ultraviolet (the wavelength range is generally defined as 400nm-450nm), mid ultraviolet (the wavelength range is generally defined as 200nm-400nm), far ultraviolet (the wavelength range is generally defined as 100nm-200nm) and extreme ultraviolet (the wavelength is less than 100 nm). The extreme ultraviolet detection mainly faces the magnetic layer and the plasma layer, most systems are in an extremely narrow band and single spectrum section imaging mode, and must be applied to a space-based platform environment, application scenes are limited, implementation difficulty is extremely high, generally, important information covered by a medium ultraviolet (wavelength range is generally defined as 200nm-400nm) region is more, and the system is an ultraviolet spectrum section for key research, and sometimes ultraviolet spectrum research is extended to near ultraviolet.
At present, ultraviolet spectrometers successfully applied at home and abroad can be basically divided into two large types. The system is based on the Rowland circle principle, is mainly used for generating laboratory ultraviolet monochromatic light, and does not have the spectral imaging capability of a space target. The other spectrometer is generally called as a C-T (Czerny-Turner) structure spectrometer, mainly comprises an incident slit, a collimator, a plane grating and a convergence imager, has various variant structures, and is widely applied to the fields of ultraviolet monochromators and ultraviolet spectral imaging.
Although the ultraviolet spectrum detection technology has been used for a long time, the technology development on the whole is behind that of visible and infrared spectrum instruments due to the restriction of the efficiency of light splitting elements such as a detector level and a grating (prism) and the like and the limitation of the types of materials. In the middle ultraviolet spectrum, the prism light splitting basically cannot realize effective dispersion and subsequent imaging, the light path is complex, the light energy loss is serious, and the practical value is not realized; the grating light splitting also faces the following unavoidable difficulties:
1) the total luminous flux of single imaging of the system is low. The dispersive type spectral imager must set a slit at the position of the inner field diaphragm to ensure that the spectral dimension and the spatial dimension do not produce aliasing (or aliasing can be distinguished or eliminated by an image processing method), and the slit is generally longer in the spatial dimension direction and very short in the spectral dimension (generally in the order of hundreds of microns), so that the total luminous flux of single imaging of the system is lower.
2) The signal-to-noise ratio is poor when imaging weak targets. In order to detect extremely weak mid-ultraviolet signals, an image enhancement type detector is generally adopted as an imaging end, and due to the fact that the device adopts an electron multiplication technology, the noise level of the detector is far higher than that of a traditional solid detector, the signal-to-noise ratio is poor when weak targets are imaged.
3) The overall detection sensitivity of the spectrometer is low. Most of the existing ultraviolet spectrometers for commercial or industrial use are optical fiber spectrometers, although the size is small, the sensitivity of the ultraviolet spectrometers in the middle ultraviolet spectrum cannot meet the requirement of accurate detection of macroscopic radiation background, even cannot realize detection because the ultraviolet spectrometers are only used in the civil field and general laboratories; the spectral band is set to be wider, so the sensitivity of the detector is not high.
4) The intensity portrayal of the full scene cannot be supported well. The detection of ultraviolet background radiation is often influenced by environmental factors such as sunlight, the intensity variation in the middle ultraviolet spectrum band is large, and even 4-5 orders of magnitude of variation may occur between the weakest signal and the strongest signal, i.e. the dynamic range reaches 104To 105Whereas conventional detectors can only support up to about 103Dynamic range (ratio of the strongest signal to the weakest detectable signal strength) and does not support a good intensity characterization of the full scene.
When ultraviolet detection with extremely high requirements on the detection sensitivity of the system is carried out, a weak target needs to be imaged, so that the requirements on the total luminous flux and the sensitivity of single imaging of the system are high, and on the premise of meeting the requirement on high signal-to-noise ratio, an ultraviolet-sensitive image enhanced detector is adopted, so that the full-scene intensity characterization requirement sometimes needs to be met, but the existing ultraviolet spectrum imager is difficult to meet the requirements.
Disclosure of Invention
The invention aims to solve the technical problems of lower luminous flux, poor signal-to-noise ratio and lower sensitivity of the existing ultraviolet spectrum imager and provides the ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity.
In order to solve the technical problems, the technical solution provided by the invention is as follows:
a high-flux, high-signal-to-noise ratio and high-sensitivity ultraviolet spectrum imager is characterized in that:
the system comprises a reflective imaging mirror, a Hadamard template, a dispersion unit, an ultraviolet sensitive image enhanced detector component and a one-dimensional translation stage which are sequentially arranged along a light path;
the primary image surface of the reflective imaging mirror is superposed with the object surface of the dispersion unit, and the Hadamard template is positioned on the superposed surface;
the length direction of each slit on the Hadamard template is orthogonal to the dispersion direction of the dispersion unit, and the width direction of each slit is consistent with the dispersion direction; the Hadamard template comprises a coding window and a coding template, and the one-dimensional translation stage is connected with the coding template and used for moving the coding template;
the ultraviolet sensitive image enhancement type detector component comprises an electronic reading system, and an ultraviolet image enhancer, an optical fiber panel and a windowable detector which are sequentially arranged along a light path; the optical fiber panel is respectively conjugated with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic reading system is electrically connected with the windowable detector;
or the ultraviolet-sensitive image enhancement type detector component comprises an electronic reading system, and an ultraviolet image enhancer, a light cone and a windowable detector which are sequentially arranged along a light path; the light cone is respectively conjugated with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic readout system is electrically connected to the windowable detector.
Further, the dispersion unit is an ultraviolet aberration correction type imaging grating.
Furthermore, the dispersion unit comprises a reflective collimating mirror, a planar blazed grating and a converging imaging mirror which are sequentially arranged along the optical path.
Further, an attenuation sheet is arranged at the incident surface of the ultraviolet image intensifier.
Furthermore, the Hadamard template is a continuous N-order template, and N is more than or equal to 3.
Further, the Hadamard template is of a reflective type or a transmission type.
Further, the convergent imaging mirror is reflective or transmissive.
Further, the radius of the reflective imaging mirror is 600mm, and the surface type is a paraboloid;
the radius of the ultraviolet aberration correction type imaging grating is 200mm, the surface type is spherical, and the imaging level is-1 level;
the size of the coding window is 10mm multiplied by 0.3mm and is made of black-dyed aluminum alloy;
the size of the coding template is 10mm multiplied by 0.5mm, and the coding template is made of ultraviolet enhanced fused quartz and is a 3-order S matrix.
Furthermore, the reflective imaging mirror and the Hadamard template are both in a self-closed form.
Compared with the prior art, the invention has the following beneficial effects:
the ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity provided by the invention is an ultraviolet spectrometer with high sensitivity and large dynamic range, which is suitable for detecting ultraviolet background radiation. Adopt hadamard template to accomplish space light path gating, and specific chromatic dispersion system and ultraviolet sensitive image enhancement mode detector subassembly, utilize the combination signal measurement mode, reduced the influence that ultraviolet spectrum imager inherent error itself brought the true value of target signal, indirectly reduce the deviation of target signal measured value and true value, the SNR of detected signal has been improved, the adoption of hadamard template has improved luminous flux, and then make ultraviolet spectrum imager wholly satisfy high sensitivity, in carrying out the ultraviolet detection that requires extremely high to system detection sensitivity, when imaging weak target, can satisfy the higher total luminous flux of single formation of image and sensitivity requirement of system, can also obtain higher SNR after guaranteeing to use ultraviolet sensitive image enhancement mode detector simultaneously, specifically as follows:
1. high flux. As one of the most important innovation points of the invention, high optical flux can not be achieved by the traditional dispersive spectral imager. As described above, the total flux of the optical system of the conventional dispersive spectral imager is limited by the area of the field diaphragm, and the effective field utilization rate of the pre-imaging system is very low, which causes serious resource waste. In the invention, the traditional slits are replaced by slit groups (Hadamard templates) with coding information, for example, complete n-order S matrix coding is selected, so that the effective optical total flux of the system is improved by about n/2 times compared with a single slit structure in a single imaging time period.
2. High signal-to-noise ratio. As mentioned above, a direct advantage of a high optical throughput is the increase in the intensity of the optical radiation arriving at the detection surface per unit time, macroscopically, the increase in the ratio between the intensity of the useful signal and the noise limit of the detector. According to the invention, target information is spatially modulated by a coding template (Hadamard template), so that various spectral imaging information reaching an image plane are superposed in different degrees, and an indirect signal enhancement effect is realized. Meanwhile, the inherent noise of the adopted ultraviolet sensitive image enhancement type detector assembly cannot increase along with the increase of the effective radiation of the target, so the signal-to-noise ratio can reach (n-2)/2 times of that of the traditional system according to the principle of combined measurement.
3. The out-of-band rejection ratio is high. Because of using the dispersive imaging grating, the free spectrum imaging position of the grating can fall on the fixed space position, and the effective area of the detector photosurface can receive the in-band spectrum imaging information very effectively, and physically isolate the influence of out-of-band ineffective light and stray light; meanwhile, the photocathode of the ultraviolet sensitive image enhancement type detector component is adopted, the response to target radiation in an ultraviolet working spectrum is high, the quantum efficiency to a non-ultraviolet spectrum is extremely low, and the out-of-band inhibition capability of the system is further improved.
4. The stray light suppression ratio outside the field of view is high. The front end of the Hadamard template and the Hadamard template are self-sealing systems, namely, after scattering reduction of stray light outside a field of view is carried out by the front end system, the probability of the stray light directly entering a follow-up system of the spectrometer at the Hadamard template is greatly reduced, even if part of stray light can enter the follow-up system, most of the stray light enters a light-transmitting area of the Hadamard template at a large angle, and under the action of a shift axis of the Hadamard template, the probability of the incident light beam of the reflective imaging mirror entering the rear part of the dispersion unit which is an ultraviolet aberration correction type imaging grating or a reflective collimating mirror is further reduced, so that the spectrometer has higher suppression capability of the stray light outside the field of view compared with the conventional spectrometer.
5. The design is flexible. The reflective collimating mirror and the convergent imaging mirror can be independently designed according to different application scenes (spectral band, field of view and the like), and the system principle is not influenced so as to meet the requirements of different detection distances and imaging sizes. The final dispersion spectrum imaging size of the detection surface of the ultraviolet sensitive image enhancement type detector assembly is determined by the field of view and the focal length of the reflective imaging mirror and the combined magnification of the reflective collimating mirror and the convergent imaging mirror. The reflective collimating mirror and the convergent imaging mirror can form required magnification (including a 1:1 magnification system) through optical design so as to realize good matching with the target surface of the detector of the ultraviolet sensitive image enhancement type detector assembly by matching with the dispersion degree of the grating.
6. The system design difficulty is low and the volume is small. The eccentricity and the off-axis amount can be adjusted according to different blaze levels of the plane blazed grating, and the inclination compensation of the image surface of the ultraviolet sensitive image enhanced detector assembly detector is combined, so that the object space effective view field of the convergent imaging lens can be reduced for different levels, and by adopting the arrangement, the system design difficulty can be reduced, and the instrument volume can be reduced.
7. The front surface of the ultraviolet image intensifier is provided with an attenuation sheet to better support full scene intensity portrayal.
Drawings
FIG. 1 is a schematic structural diagram of an embodiment of the present invention;
fig. 2 is a schematic diagram of a coding window of a hadamard template according to an embodiment of the present invention, wherein 1, 2, and 3 represent different positions on the coding window;
fig. 3 is a schematic diagram of an encoding template of a hadamard template according to an embodiment of the present invention, wherein 1 is 1 in matrix operation, representing that a transparent region is On, 0 is 0 in matrix operation, representing that an opaque region is Off;
FIG. 1 is a drawing showing reference numerals:
the device comprises a 1-reflection type imaging mirror, a 2-Hadamard template, a 21-coding window, a 22-coding template, a 3-ultraviolet aberration correction type imaging grating, a 4-ultraviolet sensitive image enhancement type detector assembly, a 5-one-dimensional translation table and a 6-attenuation sheet.
Detailed Description
The invention is further described below with reference to the figures and examples.
An ultraviolet spectrum imager with high flux, high signal-to-noise ratio and high sensitivity is shown in fig. 1 to 3 and comprises a reflective imaging mirror 1, a Hadamard template 2, a dispersion unit, an ultraviolet sensitive image enhancement type detector component 4 and a one-dimensional translation stage 5 which are sequentially arranged along a light path; the primary image surface of the reflective imaging mirror 1 is coincided with the object surface of the dispersion unit, and the Hadamard template 2 is positioned on the coincident surface; the length direction of each slit on the Hadamard template 2 is orthogonal to the dispersion direction of the dispersion unit, and the width direction is consistent with the dispersion direction; the Hadamard template 2 comprises a coding window 21 and a coding template 22, and the one-dimensional translation stage 5 is connected with the coding template 22 and used for moving the coding template 22; the ultraviolet sensitive image enhancement type detector component 4 comprises an electronic reading system, an ultraviolet image enhancer, an optical fiber panel and a windowable detector which are sequentially arranged along a light path; the optical fiber panel is respectively conjugated with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic reading system is electrically connected with the windowable detector; or, the ultraviolet-sensitive image-enhanced detector component 4 comprises an electronic reading system, and an ultraviolet image enhancer, a light cone and a windowable detector which are sequentially arranged along a light path; the light cone is respectively conjugated with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic readout system is electrically connected to the windowable detector.
The dispersion unit comprises a reflective collimating mirror, a plane blazed grating and a convergent imaging mirror which are sequentially arranged along a light path. The reflective collimating mirror and the convergent imaging mirror can be independently designed according to different application scenes (spectral band, field of view and the like), and the system principle is not influenced so as to meet the requirements of different detection distances and imaging sizes. And designing the field of view and the focal length of the reflective imaging mirror 1 and the combined magnification of the reflective collimating mirror and the convergent imaging mirror according to the final dispersion spectrum imaging size of the detection surface of the ultraviolet-sensitive image enhancement type detector assembly 4. The tangent value of the field angle (sagittal direction) of the reflective imaging mirror 1 is multiplied by the focal length thereof to obtain a primary image plane line field (corresponding to the long direction of the encoding template pattern), and the focal length ratio of the convergent imaging mirror and the reflective collimating mirror is the combined magnification ratio of the convergent imaging mirror and the reflective collimating mirror.
By adopting the structure, the design parameters of the reflective imaging mirror 1 and the details of the Hadamard template 2 can determine the spatial resolution of the system, and the reflective collimating mirror and the convergent imaging mirror can form the required magnification (including a 1:1 magnification system) through optical design so as to realize good matching with the target surface of the detector by matching with the dispersion degree of the grating.
The device can adjust the eccentricity and the off-axis amount according to different blaze levels of the plane blazed grating, and combines the inclination compensation of the detector image plane (detection plane), so that the object space effective view field of the convergent imaging lens can be reduced for different levels, and by adopting the arrangement, the system design difficulty can be reduced, and the instrument volume can be reduced.
The convergent imaging mirror is reflective or transmissive. The transmission type structure is simple, the reflection type structure and the processing process are complex, and the transmission type structure has the advantages of small volume and space saving.
The incident surface of the ultraviolet image intensifier can be provided with an attenuation sheet 6, and the attenuation rate of the attenuation sheet 6 is determined according to the variation range between the strongest signal and the weakest detectable signal intensity, so that full-scene intensity portrayal can be well supported. If the intensity of the strongest signal and the weakest detectable signal of the input signal exceeds the dynamic range of the ultraviolet enhanced detector, the attenuation sheet needs to be arranged, and the attenuation principle of the attenuation sheet is as follows: the imaging position of the weakest signal is not attenuated, and the signal beyond the dynamic range is attenuated to the dynamic range of the detector through the attenuation sheet so as to realize accurate detection. The attenuation rate of the strong signal corresponding to the imaging position needs to be determined according to the ratio of the signal intensity value of the ultraviolet image enhancement detector close to saturation to the signal intensity of the part. If the strongest signal is 10000 and the detector is close to the saturation signal intensity of 1000, the attenuation rate of the attenuation sheet in the imaging area of the strongest signal is lower than 1000/10000-1/10-10%.
The working method comprises the following steps:
arranging a Hadamard template 2 with a light path gating function on a primary image surface of the reflective imaging mirror 1, wherein the length direction of each slit on the Hadamard template 2 is orthogonal to the dispersion direction of the dispersion unit; the coded light path is collimated through a reflective collimating mirror, the collimated light beam reaches a planar blazed grating to be dispersed, the dispersed light beam passes through a convergent imaging mirror, and coded light imaging information of various colors is obtained at the cathode of an ultraviolet sensitive image enhanced detector component 4, namely the projection value measurement process of target information passing through the template of the order is completed, the corresponding imaging acquisition of each order of template is completed, namely the projection value measurement process of the target information passing through a Hadamard template 2 is completed. After the measurement is finished, a computer system and the like can be utilized to obtain the target spectrum data cube through the inverse transformation of the Hadamard template 2.
Or, the dispersion unit is an ultraviolet aberration correction type imaging grating 3. The difference from the working method is only that: the coded light path passes through the ultraviolet aberration correction type imaging grating 3 and reaches the cathode of the ultraviolet sensitive image enhancement type detector component 4, and the coded light imaging information of each color is obtained at the cathode.
The Hadamard template 2 is of a reflective type or a transmission type. The Hadamard template 2 is a continuous N-order template, and N is more than or equal to 3. After a target is imaged on a primary image surface position of the target through a reflective imaging mirror 1, the image is modulated through an optical template (Hadamard template 2) with continuously changing N orders, each order of the template corresponds to one spatial gating of an image surface, the N-order template needs to be gated and combined for N times, in each imaging process, imaging light beams in a transmission area (corresponding to the transmission area of the template and 1 in matrix operation) of the primary image surface are subjected to dispersion and convergence to form superposition of different degrees on a detector surface, and the physical process of combined spectrum measurement is achieved.
The principle of the ultraviolet spectrum imager for improving the signal-to-noise ratio of the detection signal is explained as follows:
the invention is established on the requirement of ultraviolet detection on the extremely high detection sensitivity of the system, and combines the objective condition of higher noise level of the ultraviolet sensitive image enhanced detector component 4, and provides a combined signal measurement mode, which reduces the influence of the inherent error of the detection system on the true value of a target signal and indirectly reduces the deviation of the measured value and the true value of the target signal so as to improve the signal-to-noise ratio of the detection signal.
For simplicity, assume λ1、λ2And λ3The actual values of three input signals to be measured, which are obtained by an ultraviolet spectrum imager (ideal system) in an ideal state, are respectively I (lambda)1)、I(λ2) And I (lambda)3) Shows that the fixed detection deviation of the ultraviolet spectrum imager (real measurement system) in the real state is deltadFor simplicity of description herein, the deviation is always considered a positive deviation and is the only error term in the system. Thus, if a signal is detected each time, after three detections are completed, it is assumed that the measured values of the measuring system are respectively I1、I2And I3. As follows:
the combined signal measurement is to superpose two signals to be measured, and because the inherent deviation of the detection system is not related to the input signal strength, the delta is measureddWithout change, we would then get 3 combined measurements as follows:
thus, three linear equations are obtained, so that the relationship between the real values of the three signals to be measured and the system response can be completely solved:
it can be seen that: the error introduced by a measuring system in the measured value is reduced by half; and, it can be concluded that the error will continue to decrease further as the order of the encoding template 22 (hadamard template 2) increases.
Examples
The dispersion unit is an ultraviolet aberration correction type imaging grating 3, and parameters of each part are as follows:
hadamard template parameters are as follows:
in the above two tables, NA represents not available, i.e. some items have no meaning because of the unified table form. Such as: the reflective imaging mirror 1 does not characterize the density.
The Hadamard template 2 is a 3-order S matrix (01101), one sampling period is 3, one coded space sampling combination is realized through the template window every time, and the spectral imaging of the bus visual field of 10mm multiplied by 0.3mm is completed for three times.
The target is imaged at the position of a primary image surface of the target through the reflective imaging mirror 1, and the position is also the conjugate position of an object space of the ultraviolet aberration correction type imaging grating 3, so that the primary image surface is used as the object surface of the ultraviolet aberration correction type imaging grating 3, the ultraviolet aberration correction type imaging grating 3 disperses and completes the convergence imaging of each spectral band light beam, and the imaging position is the conjugate surface of the image space of the imaging grating, namely the detection surface of the ultraviolet sensitive image enhancement type detector component 4.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same, and it is obvious for a person skilled in the art to modify the specific technical solutions described in the foregoing embodiments or to substitute part of the technical features, and these modifications or substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions protected by the present invention.
Claims (9)
1. A high flux, high signal-to-noise ratio and high sensitivity ultraviolet spectral imager is characterized in that:
the system comprises a reflective imaging mirror (1), a Hadamard template (2), a dispersion unit, an ultraviolet sensitive image enhanced detector component (4) and a one-dimensional translation stage (5) which are sequentially arranged along a light path;
the primary image surface of the reflective imaging mirror (1) is superposed with the object surface of the dispersion unit, and the Hadamard template (2) is positioned on the superposed surface;
the length direction of each slit on the Hadamard template (2) is orthogonal to the dispersion direction of the dispersion unit, and the width direction is consistent with the dispersion direction; the Hadamard template (2) comprises a coding window (21) and a coding template (22), and the one-dimensional translation stage (5) is connected with the coding template (22) and used for moving the coding template (22);
the ultraviolet sensitive image enhancement type detector component (4) comprises an electronic reading system, an ultraviolet image enhancer, an optical fiber panel and a windowable detector which are sequentially arranged along a light path; the optical fiber panel is respectively coupled with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic reading system is electrically connected with the windowable detector;
or the ultraviolet sensitive image enhancement type detector component (4) comprises an electronic reading system, an ultraviolet image intensifier, an optical fiber cone and a windowable detector which are sequentially arranged along a light path; the optical fiber cone is respectively coupled with the ultraviolet image intensifier and the detection surface of the window-openable detector, and the detection surface of the window-openable detector is positioned at the image surface of the dispersion unit; the electronic readout system is electrically connected to the windowable detector.
2. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as in claim 1 wherein:
the dispersion unit is an ultraviolet aberration correction type imaging grating (3).
3. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as in claim 1 wherein:
the dispersion unit comprises a reflective collimating mirror, a plane blazed grating and a convergent imaging mirror which are sequentially arranged along a light path.
4. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as in claim 1 wherein:
and an attenuation sheet is arranged at the incident surface of the ultraviolet image intensifier.
5. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as in claim 1 wherein:
the Hadamard template (2) is a continuous N-order template, and N is more than or equal to 3.
6. The high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager of claim 5, wherein:
the Hadamard template (2) is of a reflection type or a transmission type.
7. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as claimed in claim 3 wherein:
the convergent imaging mirror is reflective or transmissive.
8. A high throughput, high signal to noise ratio, high sensitivity ultraviolet spectral imager in accordance with claim 2 wherein:
the radius of the reflective imaging mirror (1) is 600mm, and the surface type is a paraboloid;
the radius of the ultraviolet aberration correction type imaging grating (3) is 200mm, the surface type is spherical, and the imaging level is-1 level;
the size of the coding window (21) is 10mm multiplied by 0.3mm, and the coding window is made of black-dyed aluminum alloy;
the size of the coding template (22) is 10mm multiplied by 0.5mm, and the coding template is made of ultraviolet enhanced fused quartz and is a 3-order S matrix.
9. A high throughput, high signal-to-noise ratio, and high sensitivity ultraviolet spectral imager as in claim 1 wherein:
the reflective imaging mirror (1) and the Hadamard template (2) are in a self-sealing form.
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