A large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system

Abstract

The present invention discloses a large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system, including a primary mirror, a secondary mirror, a visible light correction optical device, and an infrared light correction optical device. The secondary mirror is a lens with a convex surface facing the primary mirror, and a spectral film that can transmit visible light and reflect infrared light is plated on the convex surface of the secondary mirror. The secondary mirror is arranged between the primary mirror and the visible light correction optical device, and the primary mirror is arranged between the secondary mirror and the infrared light correction optical device. The present invention can meet high requirements such as large aperture, large field of view, and wide band; by coating the secondary mirror, the problem of subsequent spectral difficulty caused by large aperture or large field of view is solved; the present invention has the advantages of short back intercept and small lens group size, and the short back intercept solves the problem of difficult light path arrangement in a limited space, and can meet the requirements of layout in a small space.

Description

Technical Field

[0001] The invention relates to an astronomical optical telescope optical system, in particular to a large-aperture wide-spectrum coaxial bidirectional layout telescope optical system. Background Art

[0002] The visible light imaging system receives the electromagnetic waves in the visible light band emitted or reflected by the observed target for optical imaging. It can observe the details of the object and detect and identify the target. However, since the visible light optical system has high requirements for light, once the light intensity becomes low, it is difficult to detect and identify the target. For objects in a non-illuminated environment, we can only rely on infrared imaging technology. The imaging quality of infrared imaging technology is not greatly affected by the lighting environment and weather conditions, but the imaging of the target by infrared imaging technology is not detailed and accurate enough, which is different from people's visual habits. To some extent, it cannot detect and identify the target. With the development of science and technology, in order to detect targets with higher resolution and more accurate detection, a wide-spectrum optical system has been developed. The wide-spectrum optical system can detect the target of the measured object in multiple bands such as visible light and infrared light, which is not available in a single-band optical system. It can obtain accurate and detailed target features in the visible light and infrared light bands. At the same time, the target exhibits different optical characteristics in different bands, which can realize wide-spectrum and high-resolution real-time detection and identification of the target, which is of great significance to both military and civilian fields. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a large-aperture, wide-spectrum, coaxial, bidirectionally arranged telescope optical system in view of the difficulty of subsequent light splitting and the difficulty of light path arrangement in a limited space caused by a large aperture or a large field of view.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system comprises a primary mirror, a secondary mirror, a visible light correction optical device and an infrared light correction optical device, wherein the secondary mirror is a lens having a convex surface facing the primary mirror, the convex surface of the secondary mirror is a spherical surface, the convex surface of the secondary mirror is plated with a spectroscopic film that can transmit visible light and reflect infrared light, the secondary mirror is arranged between the primary mirror and the visible light correction optical device, and the primary mirror is arranged between the secondary mirror and the infrared light correction optical device; the primary mirror is used to receive external parallel light, the external parallel light is reflected by the primary mirror to form a first reflected light, the first reflected light is divided into two paths of light after passing through the secondary mirror, one path is reflected by the secondary mirror to form a second reflected light, and the other path is transmitted by the secondary mirror to form a transmitted light, the second reflected light is transmitted through the infrared light correction optical device to reach a first detector, and the transmitted light is transmitted through the visible light correction optical device to reach a second detector.

[0006] Furthermore, the visible light correction optical device includes a first correcting mirror, a second correcting mirror, a third correcting mirror and a fourth correcting mirror arranged in sequence, the first correcting mirror and the fourth correcting mirror are positive meniscus lenses, the second correcting mirror is a double concave lens, and the third correcting mirror is a double convex lens.

[0007] Furthermore, the distance between the first correcting mirror and the second correcting mirror is 58.5 mm, the distance between the second correcting mirror and the third correcting mirror is 74.7 mm, and the distance between the third correcting mirror and the fourth correcting mirror is 1.3 mm.

[0008] Furthermore, the infrared light correction optical device includes a fifth correcting mirror, a sixth correcting mirror, a seventh correcting mirror, an eighth correcting mirror and a ninth correcting mirror, wherein the fifth correcting mirror and the eighth correcting mirror are negative meniscus lenses, and the sixth correcting mirror, the seventh correcting mirror and the ninth correcting mirror are positive meniscus lenses.

[0009] Furthermore, the distance between the fifth corrector mirror and the sixth corrector mirror is 2.75 mm, the distance between the sixth corrector mirror and the seventh corrector mirror is 0.125 mm, the distance between the seventh corrector mirror and the eighth corrector mirror is 17.4 mm, and the distance between the eighth corrector mirror and the ninth corrector mirror is 0.1 mm.

[0010] Furthermore, the primary mirror is an aspherical reflector with an aperture greater than 400 mm, and a hole is provided in the middle of the primary mirror to allow the reflected light of the secondary mirror to pass through.

[0011] Furthermore, the secondary mirror adopts a fused quartz lens.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention solves the problem of subsequent light splitting difficulty caused by large aperture or large field of view by coating the secondary mirror; the shorter back intercept solves the problem of difficult light path arrangement in a limited space. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the present invention.

[0015] Figure 2 It is a schematic diagram of the structure of the visible light correction system of the present invention.

[0016] Figure 3 It is a schematic diagram of the structure of the infrared light correction system of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0018] This embodiment provides a Figure 1The large-aperture wide-spectrum coaxial bidirectional layout telescope optical system shown in the figure comprises a primary mirror 1, a secondary mirror 2, a visible light correction optical device 3 and an infrared light correction optical device 4. The primary mirror 1 is an aspherical reflector with an aperture greater than 400 mm, and a hole is provided in the middle of the primary mirror 1 to allow the reflected light of the secondary mirror 2 to pass through. The secondary mirror 2 is a lens with a convex surface facing the primary mirror 1, the convex surface of the secondary mirror 2 is a spherical surface, and a spectroscopic film that can transmit visible light and reflect infrared light is coated on the convex surface of the secondary mirror 2. The secondary mirror 2 preferably adopts a fused quartz lens. The secondary mirror 2 is arranged between the primary mirror 1 and the visible light correction optical device 3, and the primary mirror 1 is arranged between the secondary mirror 2 and the infrared light correction optical device 4. The main mirror 1 is used to receive external parallel light 14. The external parallel light 14 is reflected and adjusted by the main mirror 1 to form a first reflected light 15. The first reflected light 15 is divided into two paths after passing through the secondary mirror 2. One path is reflected and adjusted by the secondary mirror 2 to form a second reflected light 16, and the other path is transmitted by the secondary mirror 2 to form a transmitted light 17. The second reflected light 16 is transmitted through the infrared light correction optical device 4 to reach the first detector, and the transmitted light 17 is transmitted through the visible light correction optical device 3 to reach the second detector.

[0019] like Figure 2 As shown, the visible light correction optical device in this embodiment includes a first correcting mirror 5, a second correcting mirror 6, a third correcting mirror 7 and a fourth correcting mirror 8 arranged in sequence, wherein the first correcting mirror 5 and the fourth correcting mirror 8 are preferably positive meniscus lenses, the second correcting mirror 6 is preferably a biconcave lens, and the third correcting mirror 7 is preferably a biconvex lens. The transmitted light 17 is transmitted through the first correcting mirror 5, the second correcting mirror 6, the third correcting mirror 7 and the fourth correcting mirror 8 in sequence to reach the detector.

[0020] Specifically, in this embodiment, the distance between the first correcting mirror 5 and the second correcting mirror 6 is 58.5 mm, the distance between the second correcting mirror 6 and the third correcting mirror 7 is 74.7 mm, and the distance between the third correcting mirror 7 and the fourth correcting mirror 8 is 1.3 mm.

[0021] like Figure 3 As shown, the infrared light correction optical device in this embodiment includes a fifth corrector 9, a sixth corrector 10, a seventh corrector 11, an eighth corrector 12 and a ninth corrector 13, wherein the fifth corrector 9 and the eighth corrector 12 are preferably negative meniscus lenses, and the sixth corrector 10, the seventh corrector 11 and the ninth corrector 13 are preferably positive meniscus lenses. The reflected light 16 is transmitted through the fifth corrector 9, the sixth corrector 10, the seventh corrector 11, the eighth corrector 12 and the ninth corrector 13 in sequence to reach the detector.

[0022] Specifically, in this embodiment, the distance between the fifth corrector 9 and the sixth corrector 10 is 2.75 mm, the distance between the sixth corrector 10 and the seventh corrector 11 is 0.125 mm, the distance between the seventh corrector 11 and the eighth corrector 12 is 17.4 mm, and the distance between the eighth corrector 12 and the ninth corrector 13 is 0.1 mm.

[0023] Specifically, the primary mirror 1 in this embodiment adopts an aspherical reflector with a diameter of 460 mm, and the secondary mirror 2 adopts a fused silica lens. The first correcting mirror 5, the second correcting mirror 6, the third correcting mirror 7, the fourth correcting mirror 8, the fifth correcting mirror 9, the sixth correcting mirror 10, the seventh correcting mirror 11, the eighth correcting mirror 12 and the ninth correcting mirror 13 all adopt spherical lenses. The secondary mirror 2 is a lens with a convex surface facing the primary mirror. The center thickness of the secondary mirror is 93 mm. The secondary mirror adopts a fused silica lens with a light-clearing diameter of 120 mm, and the convex surface of the lens is a spherical surface. The convex surface of the secondary mirror 2 is coated for spectroscopy. The coating layer of the convex surface of the secondary mirror 2 is an AG+ZNS film layer. The convex surface of the secondary mirror 2 spectroscopy the light reflected by the primary mirror, transmits visible light, and reflects infrared light.

[0024] In summary, the present invention discloses an optical system of a large-aperture wide-spectrum coaxial telescope, including a primary mirror, a secondary mirror, a visible light correction system and an infrared light correction system, wherein the visible light correction system includes a correction mirror 1, a correction mirror 2, a correction mirror 3 and a correction mirror 4, and the infrared light correction system includes a correction mirror 5, a correction mirror 6, a correction mirror 7, a correction mirror 8 and a correction mirror 9. The secondary mirror is located between the visible light correction system and the primary mirror, and the primary mirror is located between the secondary mirror and the infrared light correction system. The present invention can meet high requirements such as large aperture, large field of view, and wide band through the above unique design, i.e., by setting the size and position of the primary mirror aperture, the size and position of the secondary mirror, the positional relationship of the nine correcting mirrors, the coating of the secondary mirror, and the selection of the film layer; the problem of subsequent light splitting difficulty caused by the large aperture or the large field of view is solved by coating the secondary mirror; the present invention has the advantages of a short back focus and a small lens group size, and the short back focus solves the problem of difficult optical path arrangement in a limited space, can meet the requirements of layout in a small space, and has great application value.

[0025] The protection scope of the present invention includes but is not limited to the above embodiments. The protection scope of the present invention shall be based on the claims. Any replacement, deformation, and improvement of the technology that can be easily thought of by technicians in this field shall fall within the protection scope of the present invention.

Claims

1. A large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system, characterized in that: The invention comprises a primary mirror (1), a secondary mirror (2), a visible light correction optical device (3) and an infrared light correction optical device (4), wherein the secondary mirror (2) is a lens having a convex surface facing the primary mirror (1), the convex surface of the secondary mirror (2) is a spherical surface, and the convex surface of the secondary mirror (2) is coated with a spectroscopic film that can transmit visible light and reflect infrared light. The secondary mirror (2) is arranged between the primary mirror (1) and the visible light correction optical device (3), and the primary mirror (1) is arranged between the secondary mirror (2) and the infrared light correction optical device (4). The primary mirror (1) is used to receive external parallel light (14), the external parallel light (14) is reflected by the primary mirror (1) to form a first reflected light (15), the first reflected light (15) is divided into two paths of light after passing through the secondary mirror (2), one path is reflected by the secondary mirror (2) to form a second reflected light (16), and the other path is transmitted by the secondary mirror (2) to form a transmitted light (17), the second reflected light (16) is transmitted through the infrared light correction optical device (4) to reach the first detector, and the transmitted light (17) is transmitted through the visible light correction optical device (3) to reach the second detector; the visible light correction optical device comprises a first correcting mirror (5), a second correcting mirror (6), a third correcting mirror (7) and a fourth correcting mirror (8) arranged in sequence, the first correcting mirror (5) and the fourth correcting mirror (8) are positive meniscus lenses, the second correcting mirror (6) is a double concave lens, and the third correcting mirror (7) is a double convex lens; the infrared light correction optical device comprises a fifth correcting mirror (5), a second correcting mirror (6), a third correcting mirror (7) and a fourth correcting mirror (8) arranged in sequence, the first correcting mirror (5) and the fourth correcting mirror (8) are positive meniscus lenses, the second correcting mirror (6) is a double concave lens, and the third correcting mirror (7) is a double convex lens; A positive mirror (9), a sixth correcting mirror (10), a seventh correcting mirror (11), an eighth correcting mirror (12) and a ninth correcting mirror (13), wherein the fifth correcting mirror (9) and the eighth correcting mirror (12) are negative meniscus lenses, and the sixth correcting mirror (10), the seventh correcting mirror (11) and the ninth correcting mirror (13) are positive meniscus lenses; the main mirror (1) is an aspheric reflector with an aperture greater than 400 mm, and a hole is provided in the middle of the main mirror (1) for allowing reflected light from the secondary mirror (2) to pass through.

2. The large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system according to claim 1, characterized in that: The distance between the first correcting mirror (5) and the second correcting mirror (6) is 58.5 mm, the distance between the second correcting mirror (6) and the third correcting mirror (7) is 74.7 mm, and the distance between the third correcting mirror (7) and the fourth correcting mirror (8) is 1.3 mm.

3. The large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system according to claim 1, characterized in that: The distance between the fifth corrector mirror (9) and the sixth corrector mirror (10) is 2.75 mm, the distance between the sixth corrector mirror (10) and the seventh corrector mirror (11) is 0.125 mm, the distance between the seventh corrector mirror (11) and the eighth corrector mirror (12) is 17.4 mm, and the distance between the eighth corrector mirror (12) and the ninth corrector mirror (13) is 0.1 mm.

4. The large-aperture, wide-spectrum, coaxial, bidirectional telescope optical system according to claim 1, characterized in that: The secondary mirror (2) is made of a fused silica lens.

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