KR101675402B1 - Optical system for photographing simultaneously dual band infrared image using multiple optical fields - Google Patents

Abstract

The present invention relates to an optical system for simultaneously capturing a dual-band wavelength image capable of converting a dual-band wavelength infrared image for long-distance, medium and short-distance targets into three or more clocks,
An optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces is a system for capturing an image of a narrow-band image of the middle infrared ray and the visible light-near-infrared ray from a dual band infrared ray including a middle infrared ray band and a visible light- A visible light-near-infrared ray detecting unit 71 for detecting an infrared image of the middle-infrared light band from the double-band infrared light; And a second visible light-near-infrared ray detecting part 73 for photographing an image in the optical clock area.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an optical system for simultaneously photographing a dual-

The present invention relates to an optical system for capturing an infrared image, and more particularly, to an optical system for capturing an infrared image, which is capable of converting a dual-band infrared image for long-distance, medium- And an optical system for simultaneously photographing a wavelength image with multiple clocks.

In the method of simultaneously photographing a dual-band wavelength image in a common optical system, first, a light beam received by a common optical system is separated into light beams of two wavelengths independently using a beam splitter, and an aberration of a common optical system is corrected by an individual rear- And a method of acquiring images of two wavelengths using a suitable detector for each wavelength band.

Therefore, the beam splitter plays an important role in the dual-band optical system. Up to now, two types of beam splitter have been proposed.

First, it is formed by a plate shape inclined at 45 degrees from the optical axis, and dichroic coating is applied to the front surface to reflect the short wavelength at 90 degrees, and the long wavelength is transmitted to divide the optical path. In the case of using a common refracting telescope, a method capable of simultaneously searching for the dual-band wavelengths of middle and far-infrared rays was proposed, and the light received from the common reflecting telescope was divided into near infrared rays (0.7-0.9 μm) and mid infrared rays (3.7-4.8 μm) Was also announced. Since these methods are air in front of the coating surface, the reflection light path has no influence due to the refractive index and can realize a relatively thin thickness, which is advantageous in light transmittance of the transmission light path. However, since the light is refracted by the light flux separator, There is a problem that the optical axis of the optical axis is eccentric and the astigmatism correction plate is additionally required.

On the other hand, a beam splitting prism combining a rhomboid prism and a 45-degree triangular prism has also been proposed. This prism has a dichroic coating on the diagonal surface of the above-mentioned rhomboid prism, The visible-near-infrared rays (0.5 to 0.9 μm) are reflected by the coated surface and the medium-infrared rays are passed through. And the visible light-near-infrared rays reflected by the 90-degree bent are bent to -90 degrees again by the above-mentioned Lombond prism, so that it is possible to match the light path with the middle infrared ray transmitted through the beam splitting prism, while the focal plane array (FPA) The size of the light beam separating prism becomes large and becomes heavy due to the lens aperture.

In addition, all of the methods disclosed so far have fixed clocks, making it difficult to apply them directly to devices that require various clock switching simultaneously. In the case of a step zoom method in which two specific timepieces must be switched within a short time in contrast to a general continuous zoom method, double clock switching is performed by inserting or rotating a lens group or the like. The step zoom has been applied not only to scanning infrared optical systems but also to optical systems for FPA detectors. When a narrow clock is viewed, a lens that was not disturbed by the optical path is inserted into the optical path when the lens is switched to a wide clock, and the clock is switched. When the interval between the driving lenses is wide, Can be implemented. Both of these methods have a disadvantage that they have a fast switching speed of less than 1 second, but must secure free space for the driving lens to be missing. In particular, in the case of a rotary type, there is a restriction that an interval between the lenses is appropriately spaced to secure an optical path of another clock. In case of the insertion type, there is a disadvantage that a position error increases according to the stroke distance of the LM guide supporting the driving lens.

On the other hand, a technology related to a 'dual-band infrared optical system' is disclosed in the following prior arts.

KR 10-1276674 B1

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a dual band wavelength image capable of converting a dual band wavelength infrared image for long distance, medium and short distance targets into three or more clocks, An object of the present invention is to provide an optical system for simultaneous photographing with multiple timepieces.

According to an aspect of the present invention, there is provided an optical system for simultaneously photographing a dual-band wavelength image according to the present invention, the dual-band infrared light including a middle infrared ray band and a visible light-near- A first visible light-near-infrared ray detecting unit for capturing an image of a clock area, an intermediate-infrared detecting unit for capturing an image of a mid-optical clock area of the mid-infrared band from the dual-band infrared ray, And a second visible light-near-infrared ray detecting unit for capturing an image of the light /

The first visible light-near-infrared ray detecting unit detects visible-near-infrared light that has passed through the narrow-gauge common reflection telescope and is separated from the light beam splitting prism through visible light-near-infrared optical systems having a plurality of lenses arranged therein. And the middle infrared ray detector includes a middle infrared ray detector for detecting a middle infrared ray in a narrow-angle region, which is separated from the light beam splitting prism and passed through an infrared ray optical system, And the second visible light-near-infrared ray detecting unit detects the second visible light-near-infrared ray detecting unit in a state where the infrared ray passes through the middle-optical clock visible-near-infrared ray optical system in which a plurality of lenses are arranged, The optical clock is characterized by photographing visible light and near infrared rays.

A middle infrared ray detector for detecting a traveling direction of a selected one of a middle infrared ray in the narrow-angle area passing through the infrared optical system and a middle infrared ray in the middle- And further comprises a clock switching mirror operable to be incident.

The light beam splitting prism is formed of a cubic material, and is made of ZnSe. The light beam splitting prism reflects visible light and near-infrared rays from the dichroic coating surface, and passes the medium-infrared rays.

A folding mirror for switching an optical axis is provided behind the main mirror of the narrow-gauge common reflection telescope, and the light beam reflected by the folding mirror is incident on the light beam separation prism.

The opto-acupuncture / narrow-vision visible light and near-infrared light optical system is characterized in that some of the plurality of lenses forming the opto-acousto-optic near-infrared optical system are rotated and positioned or deviated from the optical path, .

The infrared optical system among the above-mentioned mid-optical timepieces is characterized in that some of the plurality of intermediate lenses constituting the infrared optical system among the above-mentioned mid-optical timepieces rotate and are positioned or separated in the optical path so that the intermediate timepiece and the optical timepiece are switched .

In the infrared optical system of the middle-optical clock, the aperture size of the intermediate focal plane, the incident angle and the main aberration are made to coincide with the intermediate focal plane of the infrared optical system during the narrow-angle focal length, and the infrared optical system among the narrow- Infrared ray relay optical system comprising a plurality of lenses in order to perform focus adjustment and to compensate for a focus change according to a temperature change.

The optical system for simultaneously photographing a dual-band wavelength image according to the present invention having the above-described structure by using multiple timepieces is characterized in that a dual-band wavelength image is captured by one common optical system using a high-magnification reflective telescope and a cube beam separation prism for long- It is possible to record multiple clock images on one equipment with additional telescoping telescope.

In addition, by arranging the folding mirror and the cubic beam separating prism that rotate the optical axis by 90 degrees, the space waste on the back of the main mirror can be minimized and miniaturization is possible.

In addition, by using a step zoom and a clock switch mirror to switch the clock, fast switching time and efficient space can be secured.

In addition, it is possible to compensate for non-de-energization of the focus movement due to the change of the optical system temperature by the focus adjusting lens, so that it can be applied to an aviation camera having a severe temperature change.

FIG. 1 is a block diagram illustrating an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple clocks.
2 is a schematic view showing an infrared optical system among a common optical system and a mid / optical clock in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces.
FIG. 3 is a schematic view showing a part of the optical system for simultaneously photographing a dual-band wavelength image according to the present invention, except for the middle / optical clock visible-near-infrared optical system.
FIG. 4A is a schematic view showing an ultraviolet-visible visible-near-infrared optical system in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces.
FIG. 4B is a schematic view showing a narrow-band visible light-near-infrared optical system in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces.
5 is a schematic view showing a narrow-band infrared optical system in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces.
6A is a schematic view showing an infrared optical system of an optical clock in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple timepieces.
FIG. 6B is a schematic view showing an infrared optical system in a focusing system in an optical system for simultaneously photographing a dual-band wavelength image according to the present invention with multiple clocks. FIG.

Hereinafter, an optical system for simultaneously photographing a dual-band wavelength image according to an embodiment of the present invention with multiple timepieces will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, an optical system for simultaneously photographing a dual-band wavelength image according to the present invention includes a dual-band infrared ray including a middle infrared ray band and a visible light-near-infrared ray band, A first visible light-near-infrared ray detecting unit (71) for photographing an image of a clock area, an intermediate infrared ray detecting unit (72) for photographing an image of a mid-optical clock area of the middle infrared ray band from the double- And a second visible light-near-infrared ray detector (73) for capturing an image of a mid-optical clock region of the visible light-near infrared ray band.

In the optical system for simultaneously photographing the dual-band wavelength image according to the present invention with multiple timepieces, the band of the infrared ray is composed of visible light and near infrared rays (0.6 to 0.9 m) and medium infrared rays (3 to 5 m) The infrared light of the dual band is capable of observing three or more clocks including the zoom optical system in the visible light and near infrared ray wavelength band and three in the infrared wavelength band.

In the present invention, visible light and near infrared rays of visible light-near infrared rays are separated from visible light-near infrared rays and narrow-angle infrared rays using a common reflection telescope 10 and a beam separation prism 14. The first visible light-near-infrared ray detecting unit 71 and the middle infrared ray detecting unit 72 take infrared images of the corresponding area / clock.

In the mid-optical clock, an infrared ray image is photographed using a separate independent optical system, that is, a mid-optical clock visible light-near-infrared optical system 50 and an infrared optical system 40 of a mid- , And the infrared ray among the mid-optical clocks uses the clock conversion mirror 60 to photograph the narrow watch and the mid-optical clock through the same middle infrared ray detection unit 72.

In addition, watches that can not be photographed by Joe-Hyup and Narrow-Eye are shot using a separate EO zoom lens.

As shown in FIG. 1, since the visible light-near-infrared region of the ultra-violet / narrow-angle clock uses a second visible-near-infrared ray detector 73 separate from the first visible-near-infrared ray detector 71, 20 and the mid-optical clock visible light-near-infrared optical system 50 have independent structures unlike the other optical systems, so that they do not need to be particularly mentioned. In the mid-optical clock 40, Any zooming optical system satisfying the constraint can be used.

The optical arrangement of each watch consists of a mid-optical clock-visible optical-near-infrared optical system (50) and a mid-optical clock infrared optical system (40) , All optical systems are limited in size to be mountable in the housing.

Further, the positions of the infrared optical system 30 and the mid-optical clock visible light-near-infrared optical system 50 during the narrow-angle clock can be changed according to the internal configuration of the optical system.

FIG. 2 shows the entire optical system except for the optic-optical clock visible-near-infrared optical system 50 constituted by an independent module. The infrared optical system 40 of the middle / optical clock is shown as being rotated by 90 degrees for convenience and is actually the same as the sight line direction of the main mirror 11 of the reflective telescope 10. The rotation of the ultra-violet / narrow-angle visible light-near-infrared optical system 20 and the infrared optical system 40 of the middle-to-the-optical clock is applied to a rotary lens group. When viewing the turning radius of rotation of each optical system, Ensure that there is no additional space required.

The reflective telescope 10 serves as a common optical system for passing a dual-band infrared ray including a mid-infrared band and a visible-near-infrared band.

The reflective telescope 10 is preferably a Ritchey-Chretien reflective telescope having a pair of cassegrain telescopes having a main mirror 11 and a sub-mirror 12 in a hyperboloid.

The double-band infrared ray received by the reflective telescope 10 is incident on the beam splitter prism 14 by turning the optical path upward by 90 degrees by the main mirror folding mirror 13. With this configuration, an optical system having a constant volume can be arranged closely in the space behind the main mirror 11 of the reflective telescope 10, so that the space behind the main mirror 11 can be utilized to the maximum. Actually, the ultra-observer / narrow-vision visible light-near-infrared optical system 20 and the infrared optical system 30 in the narrow-angle view can be disposed within 100 mm except for the mechanical part.

The cube beam separating prism 14 separates the double-band infrared ray passing through the reflective telescope 10 into ultra-violet / narrow-angle visible light-near infrared rays and narrow-angle infrared rays. The light beam splitting prism 14 is made of ZnSe. The light beam splitting prism 14 made of ZnSe can not transmit a wavelength of 0.6 μm or less due to its material properties. In this light beam splitting prism 14, visible light and near-infrared rays having a wavelength of 0.6 m or more are reflected by the dichroic coating surface 14a, and the intermediate infrared ray having a wavelength of 3 탆 or more passes through the dichroic Passes through the coating surface 14a and passes through the beam separating prism 14.

The aberration generated in the reflective telescope 10 and the light beam splitting prism 14 is removed from the optical system through which light passing through the light beam splitting prism 14 passes.

The electro-optic (EO) optical system 20 passes through the visible-narrow-spectrum visible light-near-infrared rays separated from the beam-separating prism 14, and the ultra-violet / narrow-angle visible light- And is detected by the visible light-near-infrared ray detector 71.

As shown in FIGS. 4A and 4B, the ultrahigh-coherence visible light and near-infrared light are reflected by the dichroic coating surface 14a of the light beam splitting prism 14, Is detected by the first visible light-near-infrared ray detector 71 through the near-infrared optical system 20. The focal length of the intermediate focal plane is determined by the common reflective telescope 10 and the light beam splitting prism 14.

In order to achieve the target performance, the ultra-diligent / narrow-band visible light-near-infrared ray optical system 20 is composed of nine lenses in total of four groups (denoted by 1 to 9 in FIGS. 4A and 4B) A lens can be applied. The ultra-violet / narrow-angle visible light-near-infrared ray optical system 20 has a structure in which an ultra-violet clock and a narrow-angle clock are integrated. That is, the ultra-violet / narrow-angle visible light-near-infrared ray optical system 20 is composed of a first lens group 21 to a fourth lens group 24, wherein the second lens group 22 and the third lens group 23 rotate (See FIG. 4A). When the second lens group 22 and the third lens group 23 are positioned in the optical path by rotation, they become narrow watches (see FIG. 4A).

Here, the clock of the ultra-miniature clock can be set to 0.5 times as much as the width-to-height of the narrow watch.

The lens installed in the ultra-violet / narrow-angle visible light-near-infrared optical system 20 will be described in detail below. The first lens group 21 is composed of one lens (2) having negative refractive power between two lenses (1, 3) having a positive refractive power, and the front lens The aspherical surface is applied. The first lens group 21 is responsible for fine focus adjustment and not only focus adjustment according to distance but also change in the refractive index of the lens caused by external temperature change and focus change due to thermal expansion or contraction of the lens barrel, You can compensate.

When the entire first-group lens 21 is moved so as to be close to the reflective telescope 10, the focal length becomes long. When the temperature rises at the reference temperature of 20 ° C, the first lens group 21 moves downward in the figure to compensate the focal plane, and when the temperature falls, the compensation direction becomes opposite. The non-thermal performance can compensate for more than 95% of the MTF (Modulation Transfer Function) based on the outermost field within operating temperature.

The two-group lens 22 and the three-group lens 23 are constituted by two pieces of lens (④), which has a negative refractive power, and two lenses (⑤), which have negative refractive power, The second lens group 22 and the third lens group 23 are formed. An aspherical surface is applied to the back surface of the fifth lens (5) of the third lens group (23) and the front surface of the sixth lens (6).

The visible light and the near-infrared light narrow-angle are realized by inserting the second-group lens 22 and the third-group lens 23 into the optic axis in the ultra-violet / narrow-range visible light-near-infrared optical system 20, Do. The main aberrations such as spherical aberration, coma aberration, and astigmatism appear largely when passing through the second lens group 22 of the third lens group 23 and the fifth lens 5 of the third lens group 23, And the aberration is corrected by the second lens (6).

When the two-group lens 22 and the three-group lens 23 are rotated in the state shown in FIG. 4A as shown in FIG. 4B, the ultra-violet / narrow-angle visible light-near-infrared optical system 20 If the rotation is switched from the ultra-narrow clock to the narrow clock and vice versa, the ultra-violet / narrow-angle visible light-near-infrared optical system 20 is switched from narrow to ultra-narrow clock. The interval between the second lens group 22 and the third lens group 23 is maintained at 30 mm or more in order to prevent the optical path from being blocked at the time of rotation.

Since the effective focal length when the ultra-violet / narrow-angle visible light-near-infrared optical system 20 operates as the ultra-violet clock is twice the intermediate focal value and the same first visible-near-infrared ray detection unit 71 is used, I have half the clock.

The fourth lens group 24 is composed of three lenses (⑦, ⑧, ⑨), and the remaining aberration of the ultra-violet / narrow-vision visible light-near-infrared optical system 20 is removed, And forms an image on the detection surface. The aspherical surface is applied to the eighth lens (8), and the last lens (9) has a negative refracting power and serves as a field flattener that corrects Petzval curvature to fit the detection surface. Then, a band-pass filter 27 for removing a wavelength region of 0.9 μm or more is used to suppress the occurrence of additional chromatic dispersion.

On the other hand, the two sheets of the folding mirrors 25 and 26 appropriately change the optical path so that the optical system is located in the main scanning inner space, and the position thereof can be appropriately disposed without interference on the optical path.

The narrow-band infrared optical system 30 allows infrared rays in narrow-angle vision separated from the beam-splitter prism 14 to pass therethrough, and the medium-infrared ray detector 72 detects infrared rays in the narrow-angle clock.

As shown in Fig. 5, the infrared ray passes through the dichroic coating surface 14a of the light beam splitting prism 14 and is incident on the folding mirror 34 during narrow-angle viewing.

Infrared rays are reflected from the folding mirror 34 to the clock switching mirror 60 and have an intermediate focal plane in front of the clock switching mirror 60. [ After passing through the medium-infrared relay optical system 74 commonly used with the mid-optical time-optical system, it is detected on the image-forming surface of the medium-infrared detecting portion 72.

The narrow-range infrared optical system 30 uses a common optical system, i.e., the reflective telescope 10, and is capable of independently controlling five groups of two (except for the medium-infrared relay optical system 74) (Indicated by (1) to (5) in FIG. 5).

The first lens group 31 is composed of two lenses made of germanium (Ge), and has a negative refracting power to increase the focal distance. The reason why the first lens group 31 has a negative refracting power is that an intermediate focal plane is formed on the light flux dividing prism 14 due to the focal length of the common reflecting telescope 10 and the beam splitting prism 14 having a high refractive index. It is difficult to arrange the optical system. Therefore, the focal length is forcibly increased by using the first-group lens 31.

The first group lens 31 is composed of two lenses (1, 2). When the first group lens 31 is composed of one lens, the optical path is very pumped in the outer region, In order to prevent an increase in the diameter of the optical system provided at the rear of the optical system.

The second lens group 32 is composed of three meniscus lenses (3, 4, 5). The second lens group 32 functions to match the aperture size, the incident angle, and the main aberration of the intermediate focal plane to the intermediate focal plane of the mid-optical clock infrared ray. To this end, the back side of the last lens (5) is formed as an aspheric surface. Also, the last lens (5) is made of silicon (Si) to suppress an increase in chromatic aberration caused by the first lens (1) to the fourth lens (4).

The first lens group 31 and the second lens group 32 are disposed at an angle of 90 degrees with respect to each other with the folding mirror 34 interposed therebetween. The optical path is switched in the mirror 34 and is incident on the second lens group 32. [

The infrared optical system 40 of the mid-optical clock has a Keplerian refracting telescope structure unlike the infrared optical system 30 during narrow-angle viewing.

As shown in Figs. 6A and 6B, the infrared optical system 40 among the above-mentioned middle-optical timepieces includes seven lenses in the 5 groups (1 to 7 in Figs. 6A and 6B Shown in FIG.

The first lens group 41 is composed of two lenses (1, 2) as an objective lens. The first lens (1) of the first lens group (41) is made of silicon (Si) and the second lens (2) is made of germanium (Ge) to suppress chromatic aberration. The aperture of the first lens (1) has the largest aperture among the lenses applied to the medium-infrared optical system. Also, in order to reduce spherical aberration caused by using a large optical aperture in a relatively high magnification system, it is preferable that the first lens group 41 is designed and manufactured to over-correct spherical aberration.

The second lens group 42 is composed of two lenses (3) and (4) having positive refractive power. The third lens (3) constituting the two-group lens 42 is composed of silicon (Si) (4) is made of germanium (Ge) to suppress the generation of chromatic aberration.

The third lens group 43 is composed of one lens (⑤) having positive oyster performance, and its material is silicon (Si) in order to suppress chromatic aberration.

The second lens group 42 and the third lens group 43 are used for switching the clock. The two-group lens 42 and the three-group lens 43 are rotatably provided on the optical axis so that the two-group lens 42 and the three-group lens 43 are arranged on the optical axis If the two-group lens 42 and the three-group lens 43 are rotated and positioned on the optical axis as shown in FIG. 6B, the optical system becomes an important system. The distance between the second lens group 42 and the third lens group 43 is arranged so as not to interfere with the optical path when the second lens group 42 and the third lens group 43 are not located on the optical axis . In addition, the front surface of the third lens (3) is made aspherical.

The four-group lens 44 and the five-group lens 45 are each composed of one lens. All are germanium (Ge) lenses. The fourth lens group 44, that is, the sixth lens (6) has a negative refracting power. The seventh lens (7) has a positive refracting power and becomes a fifth lens group 45. The fourth lens group 44 uniformly bundles the optical path diverged by the fourth lens group 44, .

In the infrared optical system 40 among the above-mentioned mid-optical timepieces, the aperture size, the incident angle, and the main aberration of the intermediate focal plane are adjusted so as to substantially coincide with the intermediate focal plane of the infrared optical system 30 during narrow- . The reason why the aperture size, the incident angle and the main aberration of the intermediate focal plane are matched is that the optical system having different diameters shares the relay lens group, and the relay lens group is arranged accordingly.

The distance between the first lens (1) and the folding mirror (46) and the distance from the folding mirror (46) to the middle infrared ray detector (72) are set so that the infrared ray optical system (40) The distance between the fingers is limited within a predetermined range. To do this, make the aspherical surface of the back surface of the first lens (1) and the second lens (2), the front surface of the sixth lens (6), and the back surface of the seventh lens (7).

The clock range of the above critical system is 3.5 times of the horizontal-vertical axis of the narrow clock, and the clock range of the optical clock is about 6 times of the horizontal-vertical axis respectively.

The clock switch mirror 60 is positioned such that it can be inserted or released behind the infrared intermediate focal plane during narrowing, as shown in Figs. 3 and 5.

When the clock switch mirror 60 is inserted, the clock switch mirror 60 covers the infrared light path of the mid / optical clock and switches the infrared light path 90 degrees during the narrow-angle clock. That is, among the mid / optical clocks, the infrared light among the mid / optical clocks incident on the infrared optical system 40 is blocked by the clock switching mirror 60 and can not proceed to the intermediate infrared detection unit 72, The infrared ray is turned by 90 degrees in the clock switching mirror 60 and is incident on the relay optical system 74. Meanwhile, when the clock switch mirror 60 is released, the infrared light of the middle / optical clocks is incident on the relay optical system 74, and infrared light of the narrow clock is inapplicable to the relay optical system 74 can not do it.

The use of the clock switch mirror 60 has the advantage that the infrared rays received by the two different objects can be imaged using one infrared ray detector 72.

The intermediate infrared relay optical system 74 is composed of four lenses in one group (see Figs. 6A and 6B). The first lens (1) and the fourth lens (4) are made of silicon (Si), the second lens (2) and the third lens (3) are made of germanium (Ge). Has the same value as the FOV (Field Of View) limited to the cold stop (75) of the infrared ray detector (72) in order to image the intermediate focal plane on the detection plane of the middle infrared ray detector (72) And serves to correct the aberration of the infrared optical system 30 among the clocks and the infrared optical system 40 of the middle and optical clocks. The fourth lens (4) controls the non-thermal refocusing according to the distance and the focal distance. When the fourth lens moves down, the focal distance becomes shorter. On the contrary, when the fourth lens moves upward, the focal distance becomes longer. When the temperature rises at the reference temperature of 20 ° C, the fourth lens (4) moves downward to compensate the focal plane. When the temperature falls, the lens moves to the opposite direction, that is, upward. In the case of the narrow-angle infrared optical system 30, it is possible to compensate for 97% of the MTF of the outermost region within the operating temperature and 92% of the critical optical system in the infrared optical system. However, since the focal length of the optical clock is short, Degradation compensation within temperature is unnecessary.

10: Common reflective telescope 11: Main mirror
12: Pupil 13: Main mirror folding mirror
14: beam separation prism 14a: dichroic coating surface
20: Ultra-violet / narrow-angle visible-near-infrared optical system
21: 1 group lens 22: 2 group lens
23: 3 group lens 24: 4 group lens
25: mirror 26: mirror
27: band-pass filter 30: narrow-band infrared optical system
31: 1 group lens 32: 2 group lens
34: Mirror 40: Infrared optical system among middle /
41: 1 group lens 42: 2 group lens
43: 3 group lens 44: 4 group lens
45: 5th lens group 46: mirror
50: Heavy-light clock visible-near-infrared optical system
60: a clock switching mirror 71: a first visible light-near infrared ray detector
72; Middle infrared ray detecting portion 73: second visible ray-near-infrared ray detecting portion
74: Medium Infrared relay optical system 75: Cold stop

Claims (8)

A first visible light-near-infrared ray detecting unit for photographing an image in the narrow-angle region of the medium-infrared and visible-near-infrared rays from a dual-band infrared ray including a middle infrared ray band and a visible light-
An infrared ray detector for capturing an image of the mid / optical clock region of the mid-infrared band from the dual band infrared ray;
And a second visible light-near-infrared ray detecting unit for capturing an image of a mid-optical clock region of the visible light-near infrared ray band from the dual-band infrared ray,
The first visible light-near-infrared ray detecting unit detects visible-near-infrared light that has passed through the narrow-gauge common reflection telescope and is separated from the light beam splitting prism through visible light-near-infrared optical systems having a plurality of lenses arranged therein. Photographing,
The intermediate-infrared ray detector includes an intermediate-to-optical time-of-day detector that detects the intermediate-to-external clock of the narrow-width region, which has passed through the infrared optical system of the narrow- A middle infrared ray in the middle / optical clock region,
Wherein the second visible light-near-infrared ray detecting unit captures a double-band wavelength image in which the double-band infrared ray is irradiated with the visible light and the near-infrared light of the middle / Optical system for simultaneous shooting with multiple clocks.
delete The method according to claim 1,
A middle infrared ray detector for detecting a traveling direction of a selected one of a middle infrared ray in the narrow-angle area passing through the infrared optical system and a middle infrared ray in the middle- Further comprising a clock switch mirror operable to be incident on the optical system.
The method according to claim 1,
The light beam splitting prism,
The optical system for simultaneously photographing a dual-band wavelength image, which is formed of a cube, made of ZnSe, reflects visible light and near-infrared light on a dichroic coating surface, and passes infrared light.
The method according to claim 1,
Wherein a folding mirror for switching an optical axis is provided behind the main mirror of the narrow-view common reflection telescope, and the light beam reflected by the folding mirror is incident on the light beam splitting prism. Optical system.
The method according to claim 1,
The ultra-violet / narrow-angle visible light-near-
Characterized in that some of the plurality of lenses constituting the ultra-violet / narrow-angle visible light-near-infrared optical system are rotated and positioned or separated from the optical path, thereby switching the narrow-band and the ultra- Optical system for shooting.
The method according to claim 1,
The infrared optical system of the above-mentioned heavy /
Wherein a part of the plurality of lenses constituting the infrared optical system among the optical and / or optical timepieces rotates and is positioned or separated from the optical path, thereby switching between an emphasis system and an optical timepiece. Optical system.
The method according to claim 1,
In the infrared optical system of the middle-optical clock, the aperture size of the intermediate focal plane, the incident angle and the major aberration coincide with the intermediate focal plane of the infrared optical system during narrow-
Wherein the infrared optical system of the narrow-width watch and the infrared optical system of the mid-optical clock share a middle IR relay optical system including a plurality of lenses for performing focus adjustment and compensating for a focus change according to a temperature change. An optical system for simultaneously photographing wavelength images with multiple clocks.

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