The high-throughput high-resolution relevant dispersion spectrum imaging device of wide spectrum
Technical field
The utility model belongs to light spectrum image-forming field, is related to a kind of high-resolution relevant dispersion spectrum of high-throughput wide spectrum
Imaging device.
Background technique
Spectral imaging technology has merged spectral technique and imaging technique, be widely used at present military affairs, agricultural, medicine,
The fields such as aerospace, environmental monitoring, Atmospheric Survey, astronomical observation.Interference and Dispersive are light spectrum image-forming fields using most
Main technology, but two kinds of technologies are all used separately under normal conditions, are only surveying wind, measurement fixed star or planet operation
The radial velocity when, both technologies can just be combined, to reach ideal measurement accuracy.
Traditional spectrometer that interference and Dispersive combine mainly there is into high-precision crossed dispersion echelon light
Spectrometer and relevant dispersive spectrometer, they have respective advantage and have obtained widely in remote sensing fields and astronomical field
Using, but still have certain problem.The former is due to using high dispersion ladder prism to cause whole system transmitance opposite
It is lower, and crossed dispersion technology can make Spectral line bend more serious, increase the difficulty of later data processing, furthermore the technology is every
It is secondary to observe single target, it observes expensive;It for the latter, can be higher by selection low resolution transmitance
Dispersive Devices make up the low disadvantage of the former transmitance, and allow single-stage time measurement, it can be achieved that multiple target detection, but due to by
The limitation of photodetector pixel, when being applied to wide range segment limit, in terms of spectral resolution and intetference-fit strengthening still
It has certain problems.
Utility model content
In order to solve traditional high-precision crossed dispersion echelle spectrograph and relevant dispersive spectrometer both spectrum
Luminous flux present in imaging method is low, photodetector target surface size limits spectrum widening, the wider fringe contrast of spectral region
Spending poorer, high spectral resolution can make the single pixel signal-to-noise ratio reduction of photodetector, crossed dispersion cause optic spectrum line curved
The problems such as bent, the utility model proposes a kind of high-resolution relevant dispersion spectrum imaging devices of high-throughput wide spectrum.
The technical solution of the utility model is to provide a kind of high-resolution relevant dispersion spectrum of high-throughput wide spectrum
Imaging device, be characterized in that including set gradually along optical path the first colimated light system, the first grating, the first lens, as
Sheer, the second lens, wide-angle Michelson interferometer, cylindrical lens, slit, the second colimated light system, the second grating, imaging lens and
Photodetector;Above-mentioned slit is located at the focal point of cylindrical lens;
Target light source is incident to the first grating after the first colimated light system collimation, through the first grating dispersion, is incident to the
After the convergence of one lens, the light of wide spectrum is cut by several narrow spectral coverages by image slicer, and narrow spectral coverage is anti-along different angle
It is incident upon the second lens, and the light that reflection direction will be reflected perpendicular to the dispersion direction of the first grating, the second lens through image slicer
It is incident to wide-angle Michelson interferometer after convergence and generates interference fringe, the interference fringe being emitted from wide-angle Michelson interferometer
It converges at slit, collimates light by slit and then by the second colimated light system, and be incident on second by cylindrical lens
On grating, and it is imaged after the direction continuation dispersion vertical with interference fringe in imaging lens, what photodetector received
Interference fringe image.
Preferably, above-mentioned first colimated light system and the second colimated light system are lens combination or arrangement of mirrors.
Preferably, above-mentioned first grating and the second grating are transmission-type grating or reflective gratings.
Preferably, the splitting ratio of the beam splitter in wide-angle Michelson interferometer is 5:5.
The invention also discloses a kind of high-resolution relevant dispersed light spectrum imaging methods of high-throughput wide spectrum, including
Following steps:
Step 1: dispersion after target light is collimated;
Step 2: the spectrum of dispersion is reflexed to the different location in space according to different spectral coverage;
Step 3: interference fringe is obtained by wide-angle Michelson interferometer is entered after the reflected beams convergence in step 2;
Step 4: interference fringe is elongated along with after the compression of interference fringe vertical direction along slit direction;
Step 5: carrying out secondary dispersion along the direction vertical with interference fringe for the interference fringe after elongating in step 4,
Obtain high throughput, wide spectrum, high-resolution spectra interference fringe;
Step 6: photodetector receives interference fringe image.
The beneficial effects of the utility model are:
(1) system for spectrometer provides more luminous energy in terms of luminous flux.This method utilizes wide-angle Michelson
Interferometer, the light being incident in interferometer need not move through collimation, and the light in big spatial angle range is allowed to be collected, improve into
Irradiating luminous flux, to also improve the sensitivity of system.
(2) realize that intetference-fit strengthening is unrelated with wavelength, the space branch period is also unrelated with wavelength.It is stepped using wide-angle
Ke Erxun interferometer, according to the relationship between specific optical path difference and incidence angle, refractive index and wavelength phase relation, the line of material are swollen
Swollen coefficient and refractive index variation with temperature coefficient, choose special construction and material completes field-compensation, dispersion compensation, temperature
Compensation, realizes the variation that the position phase of interference fringe can be detected in entire service band.
(3) it solves the problems, such as mutually to limit between the ranks number of photodetector pixel and wide spectrum.The program is first
By grating by light beam dispersion, then the light of wide spectrum is cut by several narrow spectral coverages by image slicer, and narrow spectral coverage is reflected
To not going together, secondary dispersion is carried out finally by the grating in rear dispersion system, to obtain higher spectral resolution.
(4) influence of the spectral width to intetference-fit strengthening is reduced.The utility model passes through first dispersion, then passes through picture
Sheer displacement, then interfere, the method for final dispersion, that is, pass through equidirectional dispersion twice, and the direction of interference fringe and color
Scattered direction is mutually perpendicular to, therefore reduces influence of the spectral coverage width to intetference-fit strengthening.
(5) Spectral line bend in above two conventional spectrometers can effectively be solved.The dispersion twice of the utility model is edge
The same direction, therefore be not in Spectral line bend phenomenon caused by prism in crossed dispersion;It can also be by the way that slit be designed to
Arcuate structure with certain curvature, small Spectral line bend, to effectively reduce the difficulty of later data processing.
Detailed description of the invention
Fig. 1 is Tthe utility model system structural schematic diagram.
Appended drawing reference in figure are as follows: the first colimated light system of 1-, the first grating of 2-, the first lens of 3-, 4- image slicer, 5- second
Lens, 6- wide-angle Michelson interferometer, 61- beam splitter, the first reflecting mirror of 62-, the second reflecting mirror of 63-, 64- compensating plate, 7-
Cylindrical lens, 8- slit, the second colimated light system of 9-, the second grating of 10-, 11- imaging lens, 12- photodetector.
Specific embodiment
The utility model is described in detail below in conjunction with specific embodiments and drawings.
The utility model is using the measurement method for interfering dispersion again after a kind of first dispersion, color after first collimating target light
It dissipates;Secondly the spectrum of dispersion is reflexed to the different location in space according to different spectral coverage;The reflected beams in step 2 are converged again
Enter wide-angle Michelson interferometer after poly- and obtains interference fringe;Interference fringe is compressed along with interference fringe vertical direction again
It is elongated afterwards along slit direction;The interference fringe after elongating in step 4 is carried out along the direction vertical with interference fringe again secondary
Dispersion obtains high throughput, wide spectrum, high-resolution spectra interference fringe;Last photodetector receives interference fringe image.
The above method can be realized using the high-resolution relevant dispersion spectrum imaging device of high-throughput wide spectrum, using wide
Angle Michelson's interferometer improves the luminous flux of system;According to field widening principle, spectrum width and striped pair are solved by compensation
The problem of than spending;Wide spectrum is cut by several narrow spectral coverages using image slicer in system, then by these narrow spectral coverage reflections in sky
Between different location, after wide-angle Michelson interferometer and intermediate-resolution grating, to realize high spectrally resolved
Rate, the problem of also reducing Spectral line bend caused by crossed dispersion, while slit can be arranged to have certain curvature radius
Arc further reduces the problem of Spectral line bend.
Can specifically be measured by device shown in FIG. 1, it will be seen from figure 1 that the device include along optical path successively
The first colimated light system 1, the first grating 2, the first lens 3, image slicer 4, the second lens 5, wide-angle Michelson interference being arranged
Instrument 6, cylindrical lens 7, slit 8, the second colimated light system 9, the second grating 10, imaging lens 11 and photodetector 12;First collimation system
System 1 and the second colimated light system 9 can be lens combination, can also be replaced with arrangement of mirrors.First grating 2 and the second grating 10
Available transmission-type grating replaces, and the utility model considers the miniaturization of system, has selected reflecting grating.Directional light passes through light
After grid diffraction, the angle of diffraction having the same for the same band, therefore the light of phase co-wavelength can be converged in by the first lens 3
Same point, and since the light of different wave length is different into grating diffration angle is crossed, so a dispersion can be obtained by the first lens 3
The light opened.Image slicer 4 carries out cutting to wide spectrum after this is beneficial to.Image slicer 4 can be incited somebody to action according to the difference of angle
Light or image carry out cutting, and according to the difference of angle, several narrow-band spectrums that can obtain cutting or image reflection
To not going together for space.The effect of second lens 5 is this also body in order to allow light beam to enter in interferometer in the form of converged light
The characteristics of having showed big visual field Michelson's interferometer can increase into the luminous flux in interferometer, to increase the spirit of system
Sensitivity.Beam splitter 61 in interferometer can be cuboidal beam splitter, also can use plate shaped beam splitter and replaces, but point
Beam ratio should keep 5:5.Compensating plate 64 in interferometer can be added in reflected light path or transmitted light path that (attached drawing is to be added in reflection
In optical path), which is made of two kinds of materials, by the design to two kinds of material categories and length, can be realized visual field benefit
It repays, dispersion compensation and temperature-compensating, while can also be used to change optical path difference.
The effect of above-mentioned cylindrical lens 7 is that the interference fringe convergence that interference light is formed is imaged at slit 8.The work of slit 8
With the entrance slit for being subsequent Dispersive Devices, it is an image planes of subsequent dispersion beam splitting system, also plays the effect for the veiling glare that disappears.
The effect of second colimated light system 9 is to be organized into directional light by the light after slit and (only depict for convenience in attached drawing
Three parallel rays) it is incident on subsequent Dispersive Devices grating.The effect of photodetector 12 is acquisition according to Wavelength distribution
Interferometric fringe signal, convert optical signals into electric signal, signal the processing such as amplified to, filtered, be inverting target component
Necessary data are provided.
The specific implementation steps are as follows:
(1) target light source is incident on the first grating after the first colimated light system, different by the dispersion of the first grating
The light of wavelength can be dispersed into the different location of the first lens according to diffraction light of the Principle of Grating Diffraction in same level, due to not
The optical diffraction angle of co-wavelength is identical, therefore after the first lens, for phase co-wavelength light after the first lens,
It can converge on a point, for white light source, after grating dispersion and lens focus, we can obtain one by color
The light to scatter.The distance between first grating and the first lens can determine the length ruler that dispersion light is obtained at lens focus
It is very little, while also determining the caliber size of the first lens, when the distance between the first grating and the first lens increase, obtain color
The length of astigmatism line is longer, and the size of required first lens is also bigger.
(2) when the light after dispersion is incident on image slicer, the light for the wide spectrum that dispersion obtains can be divided
At several narrow spectral coverages (being divided into 3 parts in Fig. 1), and by different spectral coverage along different angle reflect, and reflection direction perpendicular to
The dispersion direction of first grating, i.e. wide spectrum are cut into three narrow spectral coverages being distributed on different height.Image slicer and
The distance between one lens are the focal length of the first lens.
(3) light reflected along image slicer is converged by the second lens through the second lens, and is entered with converging beam
In interferometer.
(4) light beam is divided into reflected light and transmitted light, reflected light passes through compensating plate, incident by beam splitter in interferometer
It to the first reflecting mirror, and is reflected, then is transmitted by beam splitter;Another through Beam into crossing the second reflecting mirror back reflection,
Again by beam splitter reflection.Two-beam meets interference condition, so that interference phenomenon can be generated.
(5) light converges at slit after interferometer outgoing by cylindrical lens, length direction point of the interference fringe along slit
Cloth, it is vertical with the dispersion direction of the first grating.Cylindrical mirror makes to project the interference hot spot at slit to be elongated along slit direction, is protected
It has demonstrate,proved interference fringe and has had sufficient distribution space in slit direction.It should be noted that the position of slit is in cylindrical lens
Focal point, and slit is the arc with certain curvature, and this is effectively improved the curvature effect of spectral line.
(6) by being collimated light by the second colimated light system, and be incident on the second grating, by light after slit
Line continues dispersion (consistent with the dispersion direction of the first grating) along with the vertical direction of interference fringe, and it is higher to obtain resolution ratio
Interference fringe.The final interference fringe image received using photodetector, carries out the data processing work of next step.