Common aperture optical system supporting independent adjustment of television infrared view field

Abstract

The invention relates to a common-aperture optical system supporting independent adjustment of a television infrared field of view, which comprises a small field of view light window, a common-aperture telescopic system, a fast scanning reflector, a field of view switching mirror group, a thermal infrared imager, a television camera, a large field of view light window and a large field of view turning mirror, the field-of-view switching mirror group comprises a first television infrared spectroscope, a second television infrared spectroscope and a television infrared reflector, four light transmission states appear through switching of the field-of-view switching mirror group, and the first television infrared spectroscope is provided with a light splitting film which allows infrared light to pass through and reflects television light; the second television infrared spectroscope is provided with a light splitting film which allows television light to pass through and reflects infrared light, the television infrared reflector is provided with a reflecting film which reflects the television light and the infrared light at the same time, and the double-view-field independent adjustment device has the advantages of being capable of achieving independent adjustment of large and small infrared view fields of a television, simple in structure and convenient to operate.

Description

Technical Field

[0001] The invention belongs to the technical field of common aperture optical systems, and in particular relates to a common aperture optical system supporting independent adjustment of television infrared fields of view. Background Art

[0002] Modern optoelectronic sighting equipment usually includes infrared thermal imagers, television cameras and laser light finders, etc., and has a wide range of applications in military strikes, fire control, reconnaissance and early warning. Improving multi-spectral integration and product stability and accuracy are two important development trends.

[0003] In the field of dual-band common aperture optical systems, the paper was published in the journal Proc. of SPI E Vol. 694069400S-1 entitled Third Generation on Infrared Optics. The article of cs discloses a device for common aperture imaging of infrared dual-band beams, which shares a front-end off-axis three-mirror telescope system, and realizes switching of medium-wave infrared and long-wave infrared large and small fields of view through a field of view switching reflector to isolate the front-end off-axis three-mirror telescope system. The publication number CN110850592B is entitled "A laser television infrared three-band optical system with scanning function". The television infrared realizes switching of television and infrared large and small fields of view through a field of view switching reflector to isolate the front-end off-axis three-mirror telescope system. However, when the field of view switching reflector of the above device is switched in and out, the two bands must work in a large field of view or a small field of view at the same time, and the two bands cannot be adjusted independently, which cannot meet the existing needs of the dual-band common aperture optical system, thereby solving the problem that when the field of view switching reflector of the original device is switched in and out, the two bands must work in a large field of view or a small field of view at the same time, and the two bands cannot be adjusted independently for imaging. Summary of the invention

[0004] The present invention provides a common aperture optical system supporting independent adjustment of television infrared field of view, which solves the technical problems that two bands must work simultaneously in a large field of view or a small field of view when a field of view switching reflector is switched in and out, and independent adjustment of imaging of the two bands cannot be achieved, and the structure is complex and the operation is inconvenient.

[0005] In order to achieve the above technical objectives, the specific technical solutions adopted by the present invention are:

[0006] A common aperture optical system supporting independent adjustment of a television infrared field of view, comprising a small field of view light window, a common aperture telescope system, a fast scanning reflector, a field of view switching mirror group, an infrared thermal imager, a television camera, a large field of view light window and a large field of view folding mirror, wherein the field of view switching mirror group is a moving component, and the field of view switching mirror group comprises a first television infrared beam splitter, a second television infrared beam splitter and a television infrared reflector, and four light transmission states appear by switching the field of view switching mirror group;

[0007] When the field of view switching mirror group adopts the first television infrared spectroscope and is in the television infrared small field of view state, the small field of view light sequentially passes through the small field of view light window, the common aperture telescope system, and the fast scanning reflector to reach the first television infrared spectroscope, and is color-separated by the first television infrared spectroscope. The small field of view light in the television band is reflected by the first television infrared spectroscope and enters the television camera, and the small field of view light in the infrared band is transmitted through the first television infrared spectroscope and enters the infrared thermal imager;

[0008] When the field of view switching mirror group adopts the second television infrared spectroscope and is in the television infrared large field of view state, the large field of view light sequentially passes through the large field of view light window and the large field of view folding mirror, reaches the second television infrared spectroscope, and is color-separated by the second television infrared spectroscope. The large field of view light of the television band is transmitted through the second television infrared spectroscope into the television camera, and the large field of view light of the infrared band is reflected by the second television infrared spectroscope into the infrared thermal imager;

[0009] When the field of view switching mirror group adopts a TV infrared reflector and is in the TV small field of view infrared large field of view state, the infrared large field of view light sequentially passes through the large field of view light window and the large field of view folding mirror to reach the TV infrared reflector, and is reflected by the TV infrared reflector to enter the infrared thermal imager, and the TV small field of view light sequentially passes through the small field of view light window, the common aperture telescope system, and the fast scanning reflector to reach the TV infrared reflector, and is reflected by the TV infrared reflector to enter the TV camera;

[0010] When the field of view switching lens group is removed and the camera is in the state of large field of view for TV and small field of view for infrared, the light of large field of view for TV passes through the large field of view light window and the large field of view folding mirror in sequence and enters the TV camera. The light of small field of view for infrared passes through the small field of view light window, the common aperture telescope system and the fast scanning reflector in sequence and enters the infrared thermal imager.

[0011] The first television infrared spectroscope is provided with a spectroscopic film that allows infrared light to pass through and reflects television light, the second television infrared spectroscope is provided with a spectroscopic film that allows television light to pass through and reflects infrared light, and the television infrared reflector is provided with a reflective film that reflects both television light and infrared light.

[0012] Furthermore, the common-aperture telescope system includes a primary mirror, a secondary mirror, a folding mirror body, a primary image plane aperture and three mirrors, wherein the primary mirror and the three mirrors are parabolic surfaces, the secondary mirror is a quadratic surface, the folding mirror body is a plane reflector, and the off-axis method is an off-axis aperture.

[0013] Furthermore, the primary image point at the primary image plane aperture forms a perfect image for the on-axis point, and an ideal lens is set at the exit pupil of the common aperture telescope system, and the image is formed on the focal plane of the ideal lens. All lens substrate materials are microcrystalline glass, and all lens structural materials are indium watt alloy.

[0014] Furthermore, the television working band adopts 0.4-0.9μm, and the infrared working band adopts 3μm-5μm or 8μm-12μm.

[0015] Furthermore, both the small field of view light window and the large field of view light window are dual-band transmission.

[0016] Furthermore, the optical axis of the small field light passing through the small field light window and the common aperture telescope system is linearly related to the angle of the normal direction of the fast scanning mirror, and the relationship between the movement angle δ of the normal line of the fast scanning mirror and the change of the optical axis is θ=2δ / β.

[0017] Furthermore, the infrared thermal imager and the television camera are secondary imaging fixed focus systems with external pupils.

[0018] Furthermore, the small field of view light window and the large field of view light window transmit both television and infrared bands, and the transmittance is required to be greater than 90% in the infrared band and greater than 94% in the television band.

[0019] Furthermore, the first television infrared spectroscope reflects the television band and transmits the infrared band. One side is coated with a television infrared spectroscope film and the other side is coated with an infrared anti-reflection film. The base material is a single crystal germanium infrared transparent crystal. The second television infrared spectroscope reflects the infrared band and transmits the television band. One side is coated with a television infrared spectroscope film and the other side is coated with a television anti-reflection film. The base material is fused quartz optical glass. The television infrared reflector reflects television and infrared bands on both sides respectively. The base material is fused quartz optical glass, and the corresponding band reflective films are coated on both sides.

[0020] The two-dimensional movement of the normal to the fast scanning reflector can achieve micro-adjustment of the optical axis direction of the TV / infrared light with a small field of view. The infrared optical axis of the TV is linearly related to the angle of the normal direction of the fast scanning reflector. With the help of electronic control, optical secondary stabilization and fast scanning compensation can be achieved, which can adapt to the gaze imaging under the high-frequency vibration or fast movement of the external turntable. The two-dimensional movement of the normal to the fast scanning reflector can achieve micro-adjustment of the optical axis direction of the TV / infrared light with a small field of view. The infrared optical axis of the TV is linearly related to the angle of the normal direction of the fast scanning reflector. With the help of electronic control, optical secondary stabilization and fast scanning compensation can be achieved, which can adapt to the gaze imaging under the high-frequency vibration or fast movement of the external turntable.

[0021] By adopting the above technical solution, the present invention can also bring the following beneficial effects:

[0022] 1. The present invention provides a common-aperture optical system that supports independent adjustment of the infrared field of view of a television. The common-aperture optical system that supports independent adjustment of the infrared field of view of a television has the advantage of independent adjustment of two bands, and can realize the free combination of the large and small fields of view of the television imaging system and the field of view of the infrared imaging system, so as to realize wide-area reconnaissance in a certain band and precise identification in another band at the same time.

[0023] 2. The present invention provides a common-aperture optical system that supports independent adjustment of the infrared field of view of a television. By using the common-aperture optical system that supports independent adjustment of the infrared field of view of a television, the micro-adjustment of the infrared optical axis of a television with a small field of view and the addition of a control loop can achieve the beneficial effect of secondary stabilization, thereby improving the stability accuracy of the aiming line on the moving platform.

[0024] 3. The present invention provides a common-aperture optical system that supports independent adjustment of the infrared field of view of a television. The common-aperture optical system that supports independent adjustment of the infrared field of view of a television does not require additional lens elements except for planar elements such as reflectors / beamsplitters for changing the direction for large-field imaging. The large-field imaging system is simple to assemble and adjust, low in cost, and easy to promote on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 The present invention is a schematic diagram of the configuration of a common aperture optical system that supports independent adjustment of a television infrared field of view.

[0027] Figure 2 The present invention is a schematic diagram of a small field of view working state of a common aperture optical system supporting independent adjustment of a television infrared field of view.

[0028] Figure 3 The present invention is a schematic diagram of a large field of view working state of a common aperture optical system supporting independent adjustment of a television infrared field of view.

[0029] Figure 4 The present invention is a schematic diagram of the working state of a common aperture optical system supporting independent adjustment of the television infrared field of view and a television small field of view and infrared large field of view.

[0030] Figure 5 The present invention is a schematic diagram of the working state of a common aperture optical system supporting independent adjustment of the television infrared field of view and a large-field-of-view infrared small-field-of-view television.

[0031] Figure 6 It is a ray tracing diagram of a common aperture telescope system of a common aperture optical system supporting independent adjustment of television infrared field of view of the present invention;

[0032] Among them: 1. Small field of view light window; 2. Common aperture telescope system; 3. Fast scanning reflector; 4. Field of view switching lens group; 5. Infrared thermal imager; 6. Television camera; 7. Large field of view light window; 8. Large field of view folding mirror; 21. Primary mirror; 22. Secondary mirror; 23. Folding mirror body; 24. Primary image plane aperture; 25. Three mirrors; 26. Exit pupil; 27. Ideal lens focal plane; 41. First television infrared spectroscope; 42. Second television infrared spectroscope; 43. Television infrared reflector. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0035] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present invention, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0036] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention. The drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0037] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0038] Example 1

[0039] In one embodiment of the present invention, Figure 1 As shown, a common aperture optical system supporting independent adjustment of television infrared field of view comprises a small field of view light window 1, a common aperture telescope system 2, a fast scanning reflector 3, a field of view switching mirror group 4, an infrared thermal imager 5, a television camera 6, a large field of view light window 7 and a large field of view folding mirror 8, the field of view switching mirror group 4 is a moving component, the field of view switching mirror group 4 comprises a first television infrared beam splitter 41, a second television infrared beam splitter 42 and a television infrared reflector 43, and four light transmission states appear by switching the field of view switching mirror group 4;

[0040] like Figure 2 As shown, when the field of view switching mirror group 4 adopts the first television infrared spectroscope 41 and is in the television infrared small field of view state, the small field of view light sequentially passes through the small field of view light window 1, the common aperture telescope system 2, and the fast scanning reflector 3 to reach the first television infrared spectroscope 41, and is color-separated by the first television infrared spectroscope 41, the small field of view light of the television band is reflected by the first television infrared spectroscope 41 and enters the television camera 6, and the small field of view light of the infrared band is transmitted through the first television infrared spectroscope 41 and enters the infrared thermal imager 5;

[0041] like Figure 3 As shown, when the field of view switching mirror group 4 adopts the second television infrared spectroscope 42 and is in the television infrared large field of view state, the large field of view light sequentially passes through the large field of view light window 7 and the large field of view folding mirror 8, reaches the second television infrared spectroscope 42, and is color-separated by the second television infrared spectroscope 42. The large field of view light of the television band is transmitted through the second television infrared spectroscope 42 and enters the television camera 6. The large field of view light of the infrared band is reflected by the second television infrared spectroscope 42 and enters the infrared thermal imager 5.

[0042] like Figure 4 As shown, when the field of view switching mirror group 4 adopts the TV infrared reflector 43 and is in the TV small field of view infrared large field of view state, the infrared large field of view light sequentially passes through the large field of view light window 7 and the large field of view folding mirror 8 to reach the TV infrared reflector 43, and is reflected by the TV infrared reflector 43 to enter the infrared thermal imager 5, and the TV small field of view light sequentially passes through the small field of view light window 1, the common aperture telescope system 2, and the fast scanning reflector 3 to reach the TV infrared reflector 43, and is reflected by the TV infrared reflector 43 to enter the TV camera 6;

[0043] like Figure 5As shown, when the field of view switching lens group 4 is removed and the system is in the state of large field of view for television and small field of view for infrared, the light of large field of view for television passes through large field of view light window 7 and large field of view folding mirror 8 in sequence and enters television camera 6, and the light of small field of view for infrared passes through small field of view light window 1, common aperture telescope system 2 and fast scanning reflector 3 in sequence and enters infrared thermal imager 5.

[0044] The first television infrared spectroscope 41 is provided with a spectroscopic film that allows infrared light to pass through and reflects television light, the second television infrared spectroscope 42 is provided with a spectroscopic film that allows television light to pass through and reflects infrared light, and the television infrared reflector 43 is provided with a reflective film that reflects both television light and infrared light.

[0045] The common aperture telescope system 2 comprises a primary mirror 21, a secondary mirror 22, a folding mirror body 23, a primary image plane aperture 24 and a third mirror 25, wherein the primary mirror 21 and the third mirror 25 are parabolic surfaces, the secondary mirror 22 is a quadratic curved surface, the folding mirror body 23 is a plane reflective mirror, and the off-axis mode is an off-axis aperture.

[0046] like Figure 6 As shown, the primary image point at the primary image plane aperture 24 forms a perfect image for the on-axis point, and an ideal lens is set at the exit pupil 26 of the common aperture telescope system 2, and the image is formed on the ideal lens focal plane 27. All lens substrate materials are microcrystalline glass, and all lens structural materials are indium watt alloy. The thermal expansion coefficients of microcrystalline glass and indium watt alloy are small and matched, ensuring that the system has a wide operating temperature of -55 degrees to +70 degrees.

[0047] The television working band adopts 0.6-0.9μm, the infrared working band adopts 3.7μm-4.8μm, and the small-field-of-view light window 1 and the large-field-of-view light window 7 are both dual-band transmission.

[0048] When the field of view is small, the two-dimensional movement of the normal direction of the fast scanning reflector 3 can achieve micro-adjustment of the small field of view TV / infrared optical axis, and the magnification of the common aperture telescope system 2 is set to β. The relationship between the movement angle δ of the normal of the fast scanning reflector 3 and the change of the optical axis is θ=2δ / β. When the field of view is small, if the azimuth movement angle of the turntable is 2δ / β, it is only necessary to move the normal direction of the fast scanning reflector 3 by an angle δ, and the optical axis changes by θ=2δ / β, so that the visual axis can be stabilized and the target can be fixed. The light of the large field of view enters the infrared thermal imager 5 or the TV camera 6 through the large field of view light window 7 and the large field of view folding mirror 8 in turn. Therefore, when the field of view is large, the two-dimensional movement of the normal of the fast scanning reflector 3 has no effect on the large field of view optical axis.

[0049] The infrared thermal imager 5 and the television camera 6 are a secondary imaging fixed focus system with an external pupil.

[0050] The small field of view light window 1 and the large field of view light window 7 transmit both television and infrared bands, and the transmittance is required to be greater than 90% in the infrared band and greater than 94% in the television band. All dual-band reflectors such as the common aperture telescope system 2, the fast scanning reflector 3 and the large field of view folding mirror 8 are required to be coated with a metal film, and the dual-band reflectivity must be greater than 97%.

[0051] The first television infrared spectroscope 41 reflects the television band and transmits the infrared band. One side is coated with a television infrared spectroscope film, and the other side is coated with an infrared anti-reflection film. The base material is single crystal germanium infrared transparent crystal, and the television reflectivity is required to be greater than 97%, and the infrared transmittance is greater than 97%; the second television infrared spectroscope 42 reflects the infrared band and transmits the television band. One side is coated with a television infrared spectroscope film, and the other side is coated with a television anti-reflection film. The base material is fused quartz optical glass, and the infrared reflectivity is required to be greater than 96%, and the television transmittance is greater than 95%; the television infrared reflector 43 reflects television and infrared bands on both sides respectively. The base material is fused quartz optical glass, and the corresponding band reflection films are coated on both sides, and the reflectivity is required to be greater than 97%.

[0052] In conclusion, the present invention has the advantages of realizing independent adjustment of large and small infrared dual viewing fields of television, and has the advantages of simple structure and convenient operation.

[0053] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A common aperture optical system supporting independent adjustment of television infrared field of view, characterized in that: The invention comprises a small field of view light window (1), a common aperture telescope system (2), a fast scanning reflector (3), a field of view switching mirror group (4), an infrared thermal imager (5), a television camera (6), a large field of view light window (7) and a large field of view folding mirror (8), wherein the field of view switching mirror group (4) is a motion component, and the field of view switching mirror group (4) comprises a first television infrared spectroscope (41), a second television infrared spectroscope (42) and a television infrared reflector (43), and four light transmission states appear by switching the field of view switching mirror group (4); When the field of view switching mirror group (4) uses the first television infrared spectroscope (41) and is in a television infrared small field of view state, the small field of view light sequentially passes through the small field of view light window (1), the common aperture telescope system (2), and the fast scanning reflector (3) to reach the first television infrared spectroscope (41), and is color-separated by the first television infrared spectroscope (41), the small field of view light in the television band is reflected by the first television infrared spectroscope (41) and enters the television camera (6), and the small field of view light in the infrared band is transmitted through the first television infrared spectroscope (41) and enters the infrared thermal imager (5); When the field of view switching mirror group (4) uses the second television infrared spectroscope (42) and is in the television infrared large field of view state, the large field of view light sequentially passes through the large field of view light window (7) and the large field of view folding mirror (8) to reach the second television infrared spectroscope (42), and is color-separated by the second television infrared spectroscope (42), the large field of view light in the television band is transmitted through the second television infrared spectroscope (42) and enters the television camera (6), and the large field of view light in the infrared band is reflected by the second television infrared spectroscope (42) and enters the infrared thermal imager (5); When the field of view switching mirror group (4) uses a television infrared reflector (43) and is in a television small field of view infrared large field of view state, the infrared large field of view light sequentially passes through the large field of view light window (7) and the large field of view folding mirror (8) to reach the television infrared reflector (43), and is reflected by the television infrared reflector (43) to enter the infrared thermal imager (5), and the television small field of view light sequentially passes through the small field of view light window (1), the common aperture telescope system (2), and the fast scanning reflector (3) to reach the television infrared reflector (43), and is reflected by the television infrared reflector (43) to enter the television camera (6); When the field of view switching mirror group (4) is removed and the state is in which the television large field of view and the infrared small field of view state, the television large field of view light sequentially passes through the large field of view light window (7) and the large field of view folding mirror (8) to enter the television camera (6), and the infrared small field of view light sequentially passes through the small field of view light window (1), the common aperture telescope system (2), and the fast scanning reflector (3) to enter the infrared thermal imager (5). The first television infrared spectroscope (41) is provided with a spectroscopic film that allows infrared light to pass through and reflects television light, the second television infrared spectroscope (42) is provided with a spectroscopic film that allows television light to pass through and reflects infrared light, and the television infrared reflector (43) is provided with a reflective film that reflects both television light and infrared light.

2. A common aperture optical system supporting independent adjustment of television infrared field of view according to claim 1, characterized in that: The common aperture telescope system (2) comprises a primary mirror (21), a secondary mirror (22), a folding mirror (23), a primary image plane aperture (24) and a third mirror (25), wherein the primary mirror (21) and the third mirror (25) are parabolic surfaces, the secondary mirror (22) is a quadratic curved surface, the folding mirror body (23) is a plane reflecting mirror, and the off-axis mode is aperture off-axis.

3. A common aperture optical system supporting independent adjustment of television infrared field of view according to claim 2, characterized in that: The primary image point at the primary image plane aperture (24) forms a perfect image with respect to the on-axis point. An ideal lens is arranged at the exit pupil (26) of the common aperture telescope system (2), and an image is formed on the ideal lens focal plane (27). All lens substrate materials are microcrystalline glass, and all lens structural materials are indium watt alloy.

4. The common aperture optical system supporting independent adjustment of television infrared field of view according to claim 3, characterized in that: The television working band adopts 0.4-0.9 μm, and the infrared working band adopts 3 μm-5 μm or 8 μm-12 μm.

5. The common aperture optical system supporting independent adjustment of television infrared field of view according to claim 4, characterized in that: The small-viewing-field light window (1) and the large-viewing-field light window (7) are both dual-band transmission.

6. A common aperture optical system supporting independent adjustment of television infrared field of view according to claim 5, characterized in that: The optical axis of the small field of view light passing through the small field of view light window (1) and the common aperture telescopic system (2) is linearly related to the angle of the normal direction of the fast scanning reflector (3), and the relationship between the movement angle δ of the normal of the fast scanning reflector (3) and the change of the optical axis is θ=2δ / β.

7. A common aperture optical system supporting independent adjustment of television infrared field of view according to claim 6, characterized in that: The infrared thermal imager (5) and the television camera (6) are a secondary imaging fixed-focus system with an external pupil.

8. The common aperture optical system supporting independent adjustment of television infrared field of view according to claim 7, characterized in that: The small viewing field light window (1) and the large viewing field light window (7) transmit two wavebands, namely television and infrared. The transmittance is required to be greater than 90% in the infrared waveband and greater than 94% in the television waveband.

9. The common aperture optical system supporting independent adjustment of television infrared field of view according to claim 8, characterized in that: The first television infrared spectroscope (41) reflects the television band and transmits the infrared band, one side is coated with a television infrared spectroscope film, and the other side is coated with an infrared anti-reflection film, and the base material is a single crystal germanium infrared transparent crystal. The second television infrared spectroscope (42) reflects the infrared band and transmits the television band, one side is coated with a television infrared spectroscope film, and the other side is coated with a television anti-reflection film, and the base material is fused quartz optical glass. The television infrared reflector (43) reflects the television and infrared bands on both sides respectively, and the base material is fused quartz optical glass, and the corresponding band reflection films are coated on both sides.

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