A mid / long-wavelength composite co-aperture cooled infrared athermal optical system

Abstract

This invention proposes a mid / long-wavelength composite co-aperture cooled infrared athermal optical system, belonging to the field of optical imaging technology. It addresses the problem of mid / long-wavelength composite, co-aperture, and athermal design in a cooled infrared imaging detection system. It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, and a twelfth lens, along with a detector protective glass, a cold aperture, and an image plane, all coaxially arranged in the direction of light propagation. It primarily receives the inherent infrared radiation from the target and background and converges it onto the photosensitive surface of the mid / long-wavelength composite cooled infrared detector. Through photoelectric conversion, the optical signal is converted into an electrical signal, achieving mid / long-wavelength composite dual-band detection. This enables reliable detection, identification, and location of targets with weak infrared signatures and high concealment, facilitating precise strikes.

Description

Technical Field

[0001] This invention belongs to the field of optical imaging technology, and in particular relates to a medium / long-wavelength composite co-aperture cooled infrared athermal optical system. Background Technology

[0002] With the rapid development of optical detection and sensing technology, cooled infrared imaging detection systems have broad application prospects in science and technology, security monitoring, national defense and military fields. This invention is based on a novel high-resolution, small-pixel mid / long-wavelength composite cooled infrared detector with dual infrared bands of 3.7μm–4.8μm and 7.7μm–10.3μm, a resolution of 640×512, and a pixel size of 20μm. Taking into full account the influence of atmospheric transmission window, detection object, and working environment, a mid / long-wavelength composite common-aperture cooled infrared athermal optical system was designed. This system exhibits excellent imaging quality within an operating temperature range of -40℃ to +60℃, can operate 24 / 7, and has strong anti-interference capabilities, effectively utilizing the performance of the infrared imaging detection system and improving its environmental adaptability.

[0003] In summary, a mid / long-wavelength composite co-aperture cooled infrared athermal optical system is proposed. Utility Model Content

[0004] In view of this, the present invention aims to propose a mid / long-wavelength composite co-aperture cooled infrared athermal optical system to solve the problem of mid / long-wavelength composite, co-aperture, and athermal design of cooled infrared imaging detection systems.

[0005] To achieve the above objectives, this utility model adopts the following technical solution to provide a mid / long-wavelength composite co-aperture cooled infrared athermal optical system, comprising:

[0006] The detector protective glass, cold aperture, and image plane are arranged coaxially in sequence along the direction of light propagation.

[0007] Furthermore, the first lens has an aspherical incident side and a spherical exit side; the ninth lens has an aspherical incident side and a spherical exit side; and the remaining lenses are all spherical lenses.

[0008] Furthermore, the first, fourth, fifth, sixth, eighth, ninth, and twelfth lenses are positive lenses; the second, third, seventh, tenth, and eleventh lenses are negative lenses.

[0009] Furthermore, the specific parameters of the optical system are shown in Table 1.

[0010] Table 1. Parameters of the Medium / Long Wavelength Composite Co-Aperture Cooled Infrared Aseptic Optical System

[0011]

[0012]

[0013] Beneficial effects:

[0014] 1. The optical system described in this invention operates in the wavelength ranges of 3.7μm to 4.8μm and 7.7μm to 10.3μm, has a focal length of 175mm, an F-number of 2, a full field-of-view distortion of ≤3%, and a field of view of 4.1° × 3.3°. The detector is a Stirling dual-band cooled infrared detector with a resolution of 640 × 512 and a pixel size of 20μm. It is a low F-number medium / long wavelength composite common aperture cooled infrared optical system, which has the characteristics of large relative aperture, high resolution, and medium / long wavelength composite common aperture.

[0015] 2. The optical system described in this invention has a transfer function of ≥0.65 for mid-wave 0 field of view and ≥0.6 for other fields of view when the Nyquist frequency is 25 lp / mm at -40℃ to +60℃, and ≥0.4 for long-wave 0 field of view and ≥0.4 for other fields of view, resulting in excellent imaging quality. Attached Figure Description

[0016] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0017] Figure 1 This is a structural diagram of a high-resolution long-wavelength cooled infrared imaging guidance optical system.

[0018] Figure 2 The modulation transfer function curve is shown at +60℃ for medium wave.

[0019] Figure 3 The modulation transfer function curve is shown at +20℃ for medium wave.

[0020] Figure 4 The modulation transfer function curve is shown at -40℃ for medium wave.

[0021] Figure 5 The modulation transfer function curve at +60℃ for long wavelength;

[0022] Figure 6 The modulation transfer function curve is shown at +20℃ for long wavelength.

[0023] Figure 7 The modulation transfer function curve is shown at -40℃ for long waves.

[0024] Figure 8The distortion grid curve for a mid-wave optical system;

[0025] Figure 9 This is the distortion grid curve for a long-wavelength optical system.

[0026] In the diagram: First lens 1; Second lens 2; Third lens 3; Fourth lens 4; Fifth lens 5; Sixth lens 6; Seventh lens 7; Eighth lens 8; Ninth lens 9; Tenth lens 10; Eleventh lens 11; Twelfth lens 12; Detector protective glass 13; Cold aperture 14; Image plane 15. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present utility model can be combined with each other, and the described embodiments are only some embodiments of the present utility model, not all embodiments.

[0028] It should be noted that the descriptions of "left," "right," "left side," "right side," "upper part," "lower part," "top," and "bottom" in this utility model are defined based on the orientation or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and are not intended to indicate or imply that the described structure must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0029] In the description of this utility model, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0030] Referring to the accompanying drawings, this embodiment provides a mid / long-wavelength composite co-aperture cooled infrared athermalized optical system, comprising:

[0031] A series of lenses are arranged coaxially along the direction of light propagation: a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, an eleventh lens 11, a twelfth lens 12, a detector protective glass 13, a cold aperture 14, and an image plane 15. The optical system receives the inherent infrared radiation from the target and background and converges it onto the photosensitive surface of the mid- / long-wave composite cooled infrared detector. Through photoelectric conversion, the optical signal is converted into an electrical signal, achieving mid- / long-wave composite dual-band detection. This allows for reliable detection, identification, and location of targets with weak infrared characteristics and high concealment, enabling precise strikes.

[0032] In this embodiment, the light-incident side of the first lens 1 is aspherical and the light-outcident side is spherical; the light-incident side of the ninth lens 9 is aspherical and the light-outcident side is spherical; the remaining lenses are all spherical lenses.

[0033] In this embodiment, the first lens 1, the fourth lens 4, the fifth lens 5, the sixth lens 6, the eighth lens 8, the ninth lens 9, and the twelfth lens 12 are positive lenses; the second lens 2, the third lens 3, the seventh lens 7, the tenth lens 10, and the eleventh lens 11 are negative lenses.

[0034] In this embodiment, the specific parameters of the optical system are shown in Table 1.

[0035] Table 1. Parameters of the Medium / Long Wavelength Composite Co-Aperture Cooled Infrared Aseptic Optical System

[0036]

[0037]

[0038] This technical solution defines the number, radius of curvature, thickness, spacing, half-aperture, and material of each lens. To adapt to mid / long-wavelength composite common aperture and extremely harsh operating environments, a secondary imaging structure is adopted in the design. Lens power is rationally matched, material properties are fully considered, and advanced aberration theory is applied to effectively balance the contradiction between optical aberrations and thermal differences. Excellent imaging quality is achieved within the operating wavelength ranges of 3.7μm–4.8μm and 7.7μm–10.3μm, and the operating temperature range of -40℃ to +60℃. The system exhibits strong environmental adaptability, efficiently leveraging the performance of the mid / long-wavelength composite infrared imaging detection system and enhancing its environmental adaptability.

[0039] The embodiments of the present invention disclosed above are merely illustrative of the present invention. The embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A mid / long wave combined common-aperture refrigeration infrared athermalization optical system, characterized in that: A first lens (1), a second lens (2), a third lens (3), a fourth lens (4), a fifth lens (5), a sixth lens (6), a seventh lens (7), an eighth lens (8), a ninth lens (9), a tenth lens (10), an eleventh lens (11), a twelfth lens (12), a detector protective glass (13), a cold aperture (14), and an image plane (15) are arranged coaxially in the direction of light propagation.

2. The mid / long wave compound co-aperture cryogenic infrared athermalized optical system according to claim 1, characterized in that: The first lens (1) has an aspherical incident side and a spherical exit side; the ninth lens (9) has an aspherical incident side and a spherical exit side; the remaining lenses are all spherical lenses.

3. The mid / long wave compound-cornified cooling infrared athermalized optical system according to claim 2, characterized in that: The first lens (1), the fourth lens (4), the fifth lens (5), the sixth lens (6), the eighth lens (8), the ninth lens (9), and the twelfth lens (12) are positive lenses; the second lens (2), the third lens (3), the seventh lens (7), the tenth lens (10), and the eleventh lens (11) are negative lenses.

4. The mid / long-wavelength composite co-aperture cooled infrared athermalized optical system according to claim 3, characterized in that: The specific parameters of the optical system are shown in Table 1. Table 1. Parameters of the Medium / Long Wavelength Composite Co-Aperture Cooled Infrared Aseptic Optical System

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