CN103529550B - Infrared broadband target simulator optical system - Google Patents
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- CN103529550B CN103529550B CN201310519728.0A CN201310519728A CN103529550B CN 103529550 B CN103529550 B CN 103529550B CN 201310519728 A CN201310519728 A CN 201310519728A CN 103529550 B CN103529550 B CN 103529550B
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Abstract
Infrared broadband target simulator optical system, relates to a kind of be applicable to test infrared shortwave and the dynamic object recognition of medium wave imaging system and the infrared target simulation optical system of follow-up control. Described system comprises Infrared scene generation device (100), objective optics system (200), coupling mirror (300) and principal view optical system (400) four parts, the infra-red radiation that Infrared scene generation device (100) sends enters coupling mirror (300) after objective optics system (200) collimation, after principal view optical system (400) expands, be imaged onto infinity again, mate with tested optical system. The service band of infrared simulation optical system of the present invention is 2.2 ~ 4.8 μ m, visual field is that ± 4 ° and emergent pupil are apart from counting for 200mm, modulation transfer function is greater than 0.6 in the time of 20lp/mm, approaches diffraction limit, can be used as the test target simulator of infrared optical system and extensive use.
Description
Technical field
The invention belongs to infrared technique field and simulation technical field, relate to a kind of infrared broadband target simulator optical system, relate in particular to a kind of be applicable to test infrared shortwave and the dynamic object recognition of medium wave imaging system and the infrared target simulation optical system of follow-up control.
Background technology
Along with the development of infrared imagery technique, infrared imaging system has been widely used in the civilian and military fields such as optical remote sensing, navigation at night, target acquisition and fire control, guidance. The important feature of modern infrared imaging system be become increasingly complex, precision, cost is also more and more higher, this makes battlefield plan-validation and not only more and more costliness of cost of flight test that it is carried out, and the useful information that each test is obtained under optimum condition is also very limited.
Infrared semi-true object emulation technology can be effective to the performance evaluation of infrared imaging system, and it can also reduce outfield flight test in a large number in addition, the spending of saving funds and shortening weapon development cycle. Therefore, semi-true object emulation technology is significant in the development process of infrared imaging system. As the core of infrared semi-true object emulation technology, utilize infrared target simulation optical system to simulate to test infrared imaging system to target scene, be one of primary study content of the each associated mechanisms in the world.
At present, due to the appearance of various infrared stealth, perturbation technique, infrared imaging system just gradually from single wave band to two waveband, broadband surveys fast-developing. Countries in the world have been developed multiple Dual band IR imaging system. Meanwhile, also become the primary study project of the each simulation centre in the world for the polychrome target simulator optical system of infrared polychrome imaging system performance test.
For broadband target simulator optical system, the overriding challenge that affects its image quality is the spectral information of different-waveband to image on same focal plane, and because this point of reason of aberration is difficult to accomplish, it is very limited that another one significant challenge is to transmit the infra-red material of broadband information, and some material price is extremely expensive. These are all restricting the development of infrared broadband target simulator optical system. The universal method of this type of optical system of design is to select at least three kinds of different infra-red materials to match at present, ensures image quality on some lens surface by aspheric surface simultaneously. Consider the costliness of material and the difficulty of aspherical mirror machining, this increases development cost greatly. Therefore ensureing on the basis of image quality in the urgent need to a kind of at present, meet cheap, be easy to processing and debug the infrared broadband target simulator optical system of requirement.
Summary of the invention
Expensive in order to solve current infrared broadband target simulator optical system, be difficult to the shortcoming that processing is debug, it is 2.2 ~ 4.8 μ m, visual field for ± 4 ° and emergent pupil are apart from the infrared simulation optical system for 200mm that the present invention proposes a kind of imaging wave band, for testing dynamic object recognition and the follow-up control of infrared imaging system, the remarkable advantage of this system is: cost performance is very high, and be easy to processing debug.
Infrared broadband target simulator optical system of the present invention comprises Infrared scene generation device, objective optics system, coupling mirror and principal view optical system four parts. Regulation is positive direction along optical path direction from left to right. The infra-red radiation that Infrared scene generation device sends enters coupling mirror after objective optics system collimation, after expanding, principal view optical system is imaged onto infinity again, mate with tested optical system, described objective optics system is made up of parallel flat, first lens, the second lens, the 3rd lens and the 4th lens successively along optical path direction, and principal view optical system is made up of the first object lens, the second object lens, field lens, the first eyepiece and the second eyepiece successively along optical path direction. The field lens that system is introduced in principal view optical system, has played the effect of pupil before and after being connected on the one hand, has also reduced on the other hand the lateral dimension of rear mirror group, makes system become compact. Simultaneity factor is utilized the method for the plane coupling mirror of 45 ° of placements in parallel light path, facilitates and in follow-up work, introduces EVAC.
The design of infrared broadband target simulator optical system of the present invention, first choose existing similar patent according to systematic parameter, afterwards according to parameter requests such as system wavelength, visual field, focal lengths, according to Aberration Theory, by adding lens, change lens position etc. is optimized it, finally obtains the optical texture of infrared broadband target simulator optical system of the present invention. In design process, this system adopts reverse optical path-tracing, to realize mating of principal view optical system emergent pupil and detected system entrance pupil.
Infrared broadband target simulator optical system is transmission-type afocal system, system enlargement ratio is 2, and this makes coupling mirror place light path beam sizes reduce half, thereby has greatly reduced the size of coupling mirror, and do not produce asymmetry aberration, be convenient to aberration correction. Objective optics system and principal view optical system design respectively and optimize, and finally more whole target simulator optical system are optimized.
System emergent pupil is positioned at 200mm place after the principal view optical system of system, can mate completely with the entrance pupil of detected infrared imaging photosystem, can realize the interference that is not subject to the outer veiling glare of system, the infra-red radiation that Infrared scene generation device sends projects infinity through principal view optical system after objective optics system collimation, finally by, short-wave infrared imaging system surveyed, to realize the inspection to this type of aims of systems recognition and tracking function.
The present invention is being only under the restrictive condition of standard sphere with two kinds of infra-red materials and lens surface entirely, considering energy transmitance, processing and debug on feasible basis, having completed a kind of service band is 2.2 ~ 4.8 μ m, visual field is that ± 4 ° and emergent pupil are apart from the infrared simulation Optical System Design for 200mm, modulation transfer function is greater than 0.6 in the time of 20lp/mm, approaches diffraction limit. System can be used as the test target simulator of infrared optical system and extensive use, and that advantage is is cheap, engineering realizability is very strong. The present invention has the following advantages:
1, the emergent pupil of this system is outside whole system outside 200mm, can meet the emergent pupil of system and the optics entrance pupil of tested infrared imaging system matches, and testing process is not subject to the interference of outer veiling glare.
The utilization of the main projection system that 2, enlargement ratio is 2, reduces generally coupling mirror place light path, greatly reduces the aberration control difficulty of disturbing light path in target light path and follow-up work, is convenient to the optimization of system.
3, the lens material of this system only limits to Si and two kinds of crystal of Ge. On meeting compared with the basis of high imaging quality, significantly reduce system manufacturing cost.
4, remove outside parallel flat, all lens surfaces of this system all adopt standard sphere, make system processing, debug and become easily, and then reduced system cost.
Brief description of the drawings
Fig. 1 is the structural representation of infrared broadband target simulator optical system of the present invention;
Modulation transfer function (MTF) schematic diagram of Fig. 2 infrared broadband target simulator optical system of the present invention.
Detailed description of the invention
Below in conjunction with accompanying drawing, technical scheme of the present invention is further described; but do not limit to so; every technical solution of the present invention is modified or is equal to replacement, and not departing from the spirit and scope of technical solution of the present invention, all should be encompassed in protection scope of the present invention.
As shown in Figure 1, infrared broadband target simulator optical system described in present embodiment, comprises Infrared scene generation device 100, objective optics system 200, coupling mirror 300, principal view optical system 400 and optics entrance pupil 500. The infra-red radiation that Infrared scene generation device 100 sends enters coupling mirror 300 after objective optics system 200 collimations, then is imaged onto infinity after principal view optical system 400 expands, and mates with optics entrance pupil 500.
Objective optics system 200 comprises a slice parallel flat 250 and the 4th lens 210, the 3rd lens 220, the second lens 230 and 240 4 lens of first lens. The 3rd lens 220 and dull and stereotyped 250 adopt Ge crystal. Its excess-three sheet lens adopt Si crystal. Parallel flat 250 is the infrared glass window for the protection of Infrared scene generation device 100.
Principal view optical system 400 comprises two eyepieces (the second eyepiece 410 and the first eyepiece 420), two object lens (the second object lens 440 and the first object lens 450) and a slice field lens 430, and field lens 430 is near the intermediate image plane between eyepiece and object lens. The second eyepiece 410 and the first object lens 450 adopt Si crystal. The first eyepiece 420, field lens 430 and the second object lens 440 adopt Ge crystal.
First to the independent design optimization of objective optics system 200, only use Si and Ge bi-material, adopt four lens to match, from the 4th lens 210 to first lens 240, it is negative, positive, negative, negative that lens strength is respectively, and its final focal length is 80mm.
Again to the independent design optimization of principal view optical system 400, equally only adopt Si and Ge bi-material, adopt two eyepieces, two object lens and a slice field lens match, from the second eyepiece 410, the first eyepiece 420), field lens 430, the second object lens 440 to first object lens 450, that lens strength is respectively is negative, positive, just, positive and negative. The final enlargement ratio of principal view optical system is 2.
Finally whole system is optimized, is finally adjusted to transfer function and is greater than 0.6 in the time of 20lp/mm, approach diffraction limit, as shown in Figure 2.
Systematic technical indicator is as follows:
Entrance pupil diameter: 70mm;
Emergent pupil distance: 200mm;
Focal length: 160mm;
Visual field: 4.0 ° × 4.0 °;
Service band: 2.2 ~ 4.8 μ m.
In present embodiment, Infrared scene generation device 100 is image Resistor Array Projector, and it is positioned on the focal plane of objective optics system 200.
In present embodiment, infrared broadband target simulator optical system can realize the infrared broadband of 2.2 ~ 4.8 μ m is stable into picture.
In present embodiment, removing the front surface of the second eyepiece 410, two surfaces of coupling mirror 300, two surfaces of lens 250 is outside plane, and other lens surface is standard sphere.
In present embodiment, principal view optical system is transmission-type afocal system, and enlargement ratio is about 2.
The concrete optical parametric (system adopts reverse Optical System Design) as shown in table 1 of optical system.
Table 1
Illustrate: 250-1 is the front surface of parallel flat 250,250-2 is the rear surface of parallel flat 250; 240-1 is the front surface of first lens 240, and 240-2 is the rear surface of first lens 240; 230-1 is the front surface of the second lens 230, and 230-2 is the rear surface of first lens 230; 220-1 is the front surface of the 3rd lens 220, and 220-2 is the rear surface of first lens 220; 210-1 is the front surface of the 4th lens 210, and 210-2 is the rear surface of first lens 210; 300-1 is the front surface of coupling mirror 300, and 300-2 is the rear surface of coupling mirror 300; 450-1 is the front surface of the first object lens 450, and 450-2 is the rear surface of the first object lens 450; 440-1 is the front surface of the second object lens 440, and 440-2 is the rear surface of the second object lens 440; 430-1 is the front surface of field lens 430, and 430-2 is the rear surface of field lens 430; 420-1 is the front surface of the first eyepiece 420, and 420-2 is the rear surface of the first eyepiece 420; 410-1 is the front surface of the second eyepiece 410, and 410-2 is the rear surface of the first eyepiece 410.
Claims (6)
1. infrared broadband target simulator optical system, it is characterized in that described infrared simulation optical system comprises Infrared scene generation device (100), objective optics system (200), coupling mirror (300) and principal view optical system (400) four parts, the infra-red radiation that Infrared scene generation device (100) sends enters coupling mirror (300) after objective optics system (200) collimation, after expanding, principal view optical system (400) is imaged onto infinity again, mate with tested optical system, described objective optics system (200) along optical path direction successively by parallel flat (250), first lens (240), the second lens (230), the 3rd lens (220) and the 4th lens (210) composition, the 3rd lens (220) and parallel flat (250) adopt Ge crystal, the 4th lens (210), the second lens (230) and first lens (240) adopt Si crystal, described principal view optical system (400) is made up of the first object lens (450), the second object lens (440), field lens (430), the first eyepiece (420) and the second eyepiece (410) successively along optical path direction, the second eyepiece (410) and the first object lens (450) adopt Si crystal, and the first eyepiece (420), field lens (430) and the second object lens (440) adopt Ge crystal.
2. infrared broadband target simulator optical system according to claim 1, is characterized in that described Infrared scene generation device (100) is image Resistor Array Projector, and it is positioned on the focal plane of objective optics system (200).
3. infrared broadband target simulator optical system according to claim 1, it is characterized in that from the 4th lens (210), the 3rd lens (220), the second lens (230) to first lens (240), it is negative, positive, negative, negative that lens strength is respectively, and its final focal length is 80mm.
4. infrared broadband target simulator optical system according to claim 1, it is characterized in that from the second eyepiece (410), the first eyepiece (420), field lens (430), the second object lens (440) to the first object lens (450), that lens strength is respectively is negative, positive, just, positive and negative.
5. infrared broadband target simulator optical system according to claim 1, is characterized in that described principal view optical system (400) is transmission-type afocal system, and enlargement ratio is 2.
6. infrared broadband target simulator optical system according to claim 1, the service band that it is characterized in that described infrared simulation optical system is 2.2 ~ 4.8 μ m, visual field is that ± 4 ° and emergent pupil are apart from being 200mm.
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| CN103759222B (en) * | 2014-02-21 | 2016-01-20 | 哈尔滨工业大学 | Adopt microlens array as four interference light path Infrared jamming simulation systems of beam-expanding element |
| CN105093356A (en) * | 2015-07-31 | 2015-11-25 | 哈尔滨工业大学 | Micro bridge structured resistor array of high energy utilization rate |
| CN106468523B (en) * | 2016-09-23 | 2018-05-22 | 哈尔滨工业大学 | A kind of infrared/laser Shared aperture the target simulator of miniaturization |
| CN106839879B (en) * | 2017-02-20 | 2018-05-22 | 哈尔滨工业大学 | A kind of Point Target and interference simulation system based on secondary imaging principle |
| CN106840615B (en) * | 2017-03-24 | 2023-04-28 | 中国工程物理研究院应用电子学研究所 | Pupil online measurement device based on imaging conjugation and calibration method |
| CN107085313B (en) * | 2017-06-13 | 2019-04-16 | 哈尔滨工业大学 | Based on the infrared imaging system spatial filter of double freedom micro-adjusting mechanism and the operating method of the filter |
| CN109814095B (en) * | 2019-01-23 | 2021-04-16 | 北京仿真中心 | Dynamic spatial position simulation method of multi-target infrared simulation system |
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