Infrared calibration mechanism suitable for small-caliber reflection-type infrared space camera

Abstract

An infrared calibration mechanism suitable for a small-caliber reflection-type infrared space camera relates to the field of infrared space camera calibration mechanisms, solves the problem that an existing calibration mechanism of an infrared space camera cannot be applied to a small-caliber infrared space camera calibration structure, and comprises a transmission assembly, a sliding assembly and a black body, the transmission assembly comprises a motor, a motor gear, a reduction gear and a transmission support. The reduction gear is installed on a transmission support, the transmission support is adjusted, and after the reduction gear is meshed with the motor gear, the transmission support is installed on the motor support; the sliding assembly comprises a sliding frame and a double-sliding-block structure enabling the sliding frame to slide, the black body is bonded to the sliding frame, and the double-sliding-block structure is fixed to the supporting frame. The infrared calibration mechanism disclosed by the utility model is simple in structure and relatively high in reliability. And meanwhile, the possibility of arranging an infrared calibration mechanism for some small-caliber cameras with smaller volumes is also improved.

Description

Technical Field

[0001] The utility model relates to the field of infrared space camera calibration mechanisms, in particular to an infrared calibration mechanism suitable for a small-caliber reflective infrared space camera. Background Art

[0002] After the satellite is in operation, the decline of system performance in the space environment, the aging and pollution of the sensing components will reduce the optical efficiency, the change of the detector working temperature and the aging of the detector will affect the detector response rate, and the aging of the electronic components will affect the amplification gain of the electronic circuit, etc. All these will reduce the detection accuracy and sensitivity of the remote sensor. For the thermal infrared channel, a black body is often used as a calibration source for calibration.

[0003] Blackbody calibration can be divided into full optical path calibration and partial optical path calibration according to the different blackbody radiation introduction points. The most direct way to calibrate the full optical path is to design a flip moving component at the front end of the remote sensor lens, and place the blackbody source component on the moving component. During calibration, the flip mechanism is driven to cover the entire entrance pupil of the remote sensor with the blackbody source, and then the temperature of the blackbody is precisely controlled. By setting the combination to different temperatures, on-board calibration is achieved. However, the full optical path calibration method for reflective infrared cameras has great reliability risks. First of all, the field of view of reflective cameras is smaller than that of transmissive cameras, and the optical aperture is larger under the same indicators, which results in a larger area of ​​the surface source blackbody at the entrance pupil position, making thermal control more difficult. The thermal control accuracy of the surface source blackbody has a great influence on the on-orbit calibration accuracy. It is difficult to ensure the accuracy and stability of the infrared calibration of the camera during its on-orbit life cycle with a large area of ​​the surface source blackbody. At the same time, the camera entrance pupil is located at the far end of the camera optical axis. This position is very sensitive to the installation position of the camera's secondary mirror, which has a great impact on the camera's imaging quality and optical axis stability. The full-aperture surface source blackbody and its attached mechanism are too large and heavy. Installing them here will affect the camera's accuracy. At the same time, the far end of the camera optical axis is also the position with the largest acceleration response during the launch process. Installing a calibration mechanism here will pose a great safety hazard.

[0004] Therefore, reflective cameras usually set a small black body on the satellite in the optical path to perform half-optical path full field calibration. The conversion relationship between the full optical path and half optical path calibration equations is determined during laboratory vacuum radiation calibration, and this conversion relationship is used during on-orbit calibration to achieve on-orbit absolute radiation calibration in the thermal infrared spectrum.

[0005] At present, the mainstream infrared calibration mechanism using the semi-optical infrared calibration method is usually installed at the primary phase position of the camera. The space of the primary phase position of some systems is narrow. The traditional calibration mechanism adopts a circular transmission disc structure, which uses the rotation of the disc to control the cutting in and out of the black body. This structure is relatively large in size, and there are many redundant structures beyond the actual moving path contour of the black body. The structure is not compact and heavy, which brings great difficulties to the overall structural design of the camera. Many small-aperture short-wave reflective infrared space cameras do not have high requirements for infrared calibration accuracy and the camera size and weight are small. For this reason, the infrared calibration mechanism is cancelled, but it also causes the detection accuracy to decrease after long-term on-orbit operation and cannot be calibrated on-orbit.

[0006] This design, due to its light weight and small size, can adapt to the narrow installation space of small-aperture cameras and the stringent quality requirements of the whole machine, and can solve this problem well. Utility Model Content

[0007] The utility model solves the problem that the existing calibration mechanism of infrared space camera cannot be applied to the calibration structure of small-caliber infrared space camera, and provides an infrared calibration mechanism suitable for small-caliber reflective infrared space camera.

[0008] An infrared calibration mechanism suitable for a small-caliber reflective infrared space camera, the infrared calibration mechanism comprising a transmission component, a sliding component and a black body;

[0009] The transmission assembly includes a motor, a motor gear, a reduction gear and a transmission bracket;

[0010] The reduction gear is installed on the transmission bracket, and the transmission bracket is adjusted so that the reduction gear is meshed with the motor gear, and then the transmission bracket is installed on the motor bracket;

[0011] The sliding assembly comprises a sliding frame and a double-sliding block structure for making the sliding frame slide. The black body is bonded to the sliding frame, and the double-sliding block structure is fixed to a supporting frame.

[0012] Beneficial effects of the utility model:

[0013] The infrared calibration mechanism of the utility model has a simple and compact structure and is light in weight, and is more adaptable to the crowded and narrow arrangement space components of the primary phase of the infrared optical system;

[0014] The infrared calibration mechanism described in the utility model adopts a double-slider structure, so that the motion mechanism has better pointing accuracy stability and structural strength; the transmission mechanism has a larger reduction ratio and better self-locking performance, which reduces the difficulty of on-track resetting.

[0015] The infrared calibration mechanism of the utility model has a simple structure and high reliability, and also improves the possibility of arranging the infrared calibration mechanism for some small-caliber reflective cameras with relatively small volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural schematic diagram of an infrared calibration mechanism suitable for a small-aperture reflective infrared space camera described in the utility model;

[0017] Figure 2 This is a schematic diagram of a rack structure in an infrared calibration mechanism structure suitable for a small-aperture reflective infrared space camera described in the utility model;

[0018] In the figure: 1. stepper motor, 2. motor bracket, 3. transmission bracket, 4. motor gear, 5. reduction gear, 6. guide rail, 7. slider, 8. carriage, 801, rack, 9. light-through hole, 10. black body, 11. support frame. DETAILED DESCRIPTION

[0019] Combination Figure 1 to Figure 2 The present embodiment is described as an infrared calibration mechanism suitable for a small-aperture reflective infrared space camera, the infrared calibration mechanism comprising a transmission assembly, a sliding assembly and a black body 10;

[0020] The transmission assembly includes a motor 1, a motor bracket 2, a motor gear 4, a reduction gear 5 and a transmission bracket 3;

[0021] The sliding assembly includes a slide 8, a rack 801, a light-through hole 9, a double slide structure consisting of a guide rail 6 and a slide 7, and a support frame 11;

[0022] The motor 1 is fixed to the motor bracket 2 by screws, and the motor gear 4 passes through the motor shaft and is fixed by pins. The reduction gear 5 is installed on the transmission bracket 3, and the transmission bracket is adjusted so that the reduction gear 5 is meshed with the motor gear 4, and then it is installed on the motor bracket 2. The black body 10 is bonded to the slide 8 with optical epoxy glue. The sliding assembly adopts a double slider structure to ensure the linear accuracy and stability. Two guide rails 6 are used to be installed on the slide 8. Each guide rail passes through two sliders 7 and then the slider is installed on the support frame 11. The motor bracket 2 is adjusted so that the reduction gear 5 is meshed with the rack 801 on the slide 8, and then the remaining support frames 11 are fixed.

[0023] The working principle of the infrared calibration mechanism described in this embodiment is:

[0024] This structure uses a stepper motor 1 with a 95x planetary reducer. The motor 1 drives the motor gear 4 to drive the reduction gear 5 meshing with it to rotate, thereby driving the meshing rack 801 to give the movable slide 8 a linear driving force. The reduction ratio of the reduction gear 5 to the motor gear 4 is 3:1. Combined with the reducer of the motor itself, there is a larger reduction ratio, and it has better self-locking performance in the vibration environment of the rocket during the rocket launch. The double slider structure composed of the guide rail 6 and the slider 7 provides better pointing accuracy stability. The stepper motor 1 drives the gear rack to control the black body 10 installed on the slide 8 to cut in or out at the first phase position of the optical system. The slide 8 has a light hole 9 in the direction of movement of the mechanism, so that light can pass through the light hole 9 to complete imaging. This mechanism completes the switching between imaging and calibration.

[0025] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0026] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An infrared calibration mechanism suitable for a small-aperture reflective infrared space camera, characterized by: The infrared calibration mechanism comprises a transmission component, a sliding component and a black body (10); The transmission assembly comprises a motor (1), a motor gear (4), a reduction gear (5) and a transmission bracket (3); The reduction gear (5) is mounted on the transmission bracket (3), and after the transmission bracket (3) is adjusted so that the reduction gear (5) is meshed with the motor gear (4), the transmission bracket (3) is mounted on the motor bracket (2); The sliding assembly comprises a slide (8) and a double slider structure for making the slide (8) slide, the black body (10) is bonded to the slide (8), a rack (801) meshing with the reduction gear (5) is mounted on the slide, and the double slider structure is fixed on a support frame (11).

2. The infrared calibration mechanism for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The motor (1) is fixedly mounted on a motor bracket (2), and the motor gear passes through the motor shaft and is fixed by a pin.

3. The infrared calibration mechanism suitable for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The double slider structure comprises a guide rail (6) and a slider (7); the two guide rails (6) are mounted on a slide frame (8), and each guide rail (6) passes through two sliders (7) and is then mounted on a support frame (11).

4. The infrared calibration mechanism for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The reduction ratio between the reduction gear (5) and the motor gear (4) is 3:

1.

5. The infrared calibration mechanism suitable for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The black body (10) is bonded to the slide frame (8) using optical epoxy adhesive.

6. The infrared calibration mechanism for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The motor (1) is driven forward or reversely to drive the gear rack to control the black body (10) installed on the slide (8) to cut in or out at the primary phase position of the optical system, thereby completing the calibration of the black body (10).

7. The infrared calibration mechanism for a small-aperture reflective infrared space camera according to claim 1, characterized in that: The slide (8) is provided with a light-through hole (9) in the direction of movement of the mechanism, so that light passes through the light-through hole (9) to complete imaging.

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