Radiation-proof photoelectric sensor

Abstract

The invention discloses an anti-radiation photoelectric sensor, which comprises an emitter and a receiver which are welded on a PCB (Printed Circuit Board) substrate, and also comprises a shielding plate, a shaping cover, a shading plate and a reflecting cover, the shielding plate and the shaping cover are made of metal materials, and the shielding plate and the shaping cover are fixedly connected to form an anti-radiation shielding cavity; the shaping cover is fixedly connected with the reflecting cover to form a reflecting light cavity; the shaping cover is provided with a limiting hole and a shaping hole, the PCB substrate is fixedly connected in the anti-radiation shielding cavity, the emitter penetrates through the limiting hole, the light-emitting face of the emitter extends into the reflection light cavity, the receiver is right opposite to the shaping hole, the shading plate is provided with a light hole, and the shading plate is inserted into the reflection light cavity and can move relative to the reflection light cavity. And reflected light can pass through the shaping hole to reach a part of the light sensing surface of the receiver through the light transmitting hole. The device can be used on the fast reflecting mirror in a space irradiation environment, and is good in reliability and low in cost.

Description

Technical Field

[0001] The invention belongs to the field of sensors, and in particular relates to an anti-radiation photoelectric sensor. Background Art

[0002] A fast-reflecting mirror is a device used to adjust the light beam between the transmitting and receiving ends. It is a key component for adjusting and stabilizing the direction of the light beam and has broad application prospects in the field of space laser communications.

[0003] The angle measuring sensor is the core component of the fast mirror and is an important guarantee for the performance accuracy of the fast mirror. The angle measuring sensor currently used on the fast mirror is mainly a capacitive angle sensor, which identifies the deflection angle of the reflective lens based on the change in the distance between the moving electrode and the fixed electrode. However, it has the following problems: (1) The capacitive angle sensor has a slow response speed and a complex back-end circuit, resulting in a large size of the entire fast mirror; (2) The back-end circuit of the capacitive angle sensor cannot achieve anti-radiation shielding and cannot be used on fast mirrors in space radiation environments (such as orbital space environments). Because the orbital space environment is affected by cosmic radiation (radiation), if the sensor cannot resist radiation, it will be easily damaged, which will cause the fast mirror to fail. Summary of the Invention

[0004] The object of the present invention is to provide a radiation-resistant photoelectric sensor so as to be used on a fast-reflecting mirror in a space radiation environment.

[0005] The anti-radiation photoelectric sensor described in the present invention includes a transmitter and a receiver welded on a PCB substrate, and also includes a shielding plate, a shaping cover, a light shielding plate and a reflector. The shielding plate and the shaping cover are both made of metal materials. The shielding plate and the shaping cover are fixedly connected to form an anti-radiation shielding cavity, and the shaping cover and the reflector are fixedly connected to form a reflective light cavity; a limiting hole and a shaping hole are provided on the shaping cover, the PCB substrate is fixedly connected to the anti-radiation shielding cavity, the transmitter passes through the limiting hole and the light-emitting surface (of the transmitter) extends into the reflective light cavity, the receiver is directly opposite the shaping hole, a light-transmitting hole is provided on the light shielding plate, the light shielding plate is inserted into the reflective light cavity and can move relative to the reflective light cavity, and the reflected light can pass through the shaping hole through the light-transmitting hole to reach part of the photosensitive surface of the receiver.

[0006] Preferably, the radiation-resistant photoelectric sensor further includes a narrowband filter located within the reflective optical cavity, secured to the shaping cover to cover the shaping aperture. The narrowband filter's center wavelength matches the wavelength of the transmitter, and its bandwidth is ±20 nm of the center wavelength. The narrowband filter can filter out the effects of external stray light on the receiver, thereby achieving higher-precision measurements.

[0007] Preferably, the shielding plate is made of tantalum metal, and the shaping cover is made of aluminum alloy, which has low cost and good radiation resistance.

[0008] Preferably, the inner surface of the reflector is a diffuse reflection surface, and the reflection light cavity is a diffuse reflection light cavity, so that the reflected light is soft and uniform, which can improve the sensor performance.

[0009] Preferably, there are two receivers, which are spaced apart in the upper and lower parts; there are two transmitters, which are located on the left and right sides of the receiver respectively; there are two shaping holes, which are spaced apart in the upper and lower parts; there are two limiting holes, which are located on the left and right sides of the shaping hole respectively.

[0010] Preferably, the two receivers are symmetrically arranged up and down, and the two transmitters are symmetrically located on the left and right sides of the receiver; the two shaping holes are symmetrically arranged up and down, and the two limiting holes are symmetrically located on the left and right sides of the shaping hole.

[0011] Preferably, the shaping hole is a square hole, and the light-transmitting hole is a square hole, with the width of the light-transmitting hole in the vertical direction being greater than d1 and less than d2; wherein d1 represents the distance between the lower edge of the shaping hole located above and the upper edge of the shaping hole located below (i.e., the width of the interval between the two shaping holes in the vertical direction), and d2 represents the distance between the upper edge of the shaping hole located above and the lower edge of the shaping hole located below. Since both the shaping hole and the light-transmitting hole are square holes, the lower edge of the shaping hole located above and the upper edge of the shaping hole located below are parallel to each other, with the zero position centered, thus avoiding nonlinear amplification of the signal. When the light shield moves, the area of ​​the light signal received by the photosensitive surfaces of the two receivers changes, and the displacement or deflection angle of the light shield movement is calculated based on this change in area.

[0012] Preferably, in the initial state (i.e., static state), the left and right edges of the light-transmitting aperture are perpendicular to the upper and lower edges of the shaping aperture. The centerline of the light-transmitting aperture, the centerline of the shaping aperture located above, and the centerline of the shaping aperture located below are all parallel and coplanar. In this initial state, the photosensitive areas of the two receivers (i.e., the areas of the receiver's photosensitive surface that can receive reflected light) are equal, simplifying displacement or angle calculations.

[0013] Preferably, the upper end of the light shield has an elliptical mounting hole for securing the light shield to the moving component to be measured, the shaping cover has a first avoidance groove, and the PCB substrate has a second avoidance groove. The first and second avoidance grooves prevent the tightening of screws when the light shield is installed on the moving component to be measured. Furthermore, the elliptical mounting hole allows for adjustment of the light shield's installation position on the moving component to be measured (reflecting the initial position and area of ​​overlap between the light-transmitting hole and the shaping hole in the reflective light cavity when the light shield is inserted).

[0014] Preferably, the shielding plate and the shaping cover are fixedly connected by gluing, which facilitates operation. The PCB substrate is square, with notches extending forward and backward at both upper corners and first through-holes extending forward and backward at both lower corners. The main body of the shaping cover has second through-holes extending forward and backward at both upper corners, and first threaded blind holes extending forward and backward at both lower corners. Third through-holes extending vertically are provided on both supports at the lower portion of the shaping cover. Locking screw holes are provided on the left and right connecting posts of the reflector, and a second threaded blind hole extending vertically is provided at the bottom of the reflector. Two screws are threadedly connected through the two first through-holes; two screws are threadedly connected through the two second through-holes; and two screws are threadedly connected through the two third through-holes to the two second blind holes, thereby achieving a fixed connection between the PCB substrate and the shaping cover, and between the shaping cover and the reflector.

[0015] The present invention has the following effects: (1) Photoelectric sensors have fast response speed and simple back-end circuits, making them more suitable for use on fast mirrors. This helps reduce the size of the fast mirror, is low-cost, and is easy to promote and apply.

[0016] (2) The radiation-resistant shielding cavity formed by the fixed connection between the shielding plate and the plastic cover can protect the transmitter and receiver from the influence of radiation, so that the photoelectric sensor has radiation resistance and is suitable for use on the fast reflection mirror in the space radiation environment, thereby improving the reliability of the fast reflection mirror.

[0017] (3) The reflective light cavity formed by the fixed connection between the shaping cover and the reflector can obtain better light quality while blocking external light, thereby improving the performance of the photoelectric sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1 is an exploded view of the radiation-resistant photoelectric sensor in an embodiment of the present invention.

[0019] Figure 2 Schematic diagram of the structure of the radiation-resistant photoelectric sensor in an embodiment of the present invention.

[0020] Figure 3 4 is a cross-sectional view of a radiation-resistant photoelectric sensor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to enable a more detailed understanding of the features and technical contents of the embodiments of the present invention, the implementation of the embodiments of the present invention is described in detail below with reference to the accompanying drawings. The accompanying drawings are for reference only and are not intended to limit the embodiments of the present invention.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms used herein are for the purpose of describing embodiments of the present invention only and are not intended to limit the present invention.

[0023] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0024] like Figures 1 to 3As shown, the radiation-resistant photoelectric sensor in an embodiment of the present invention includes a shielding plate 1, a receiver 2, a transmitter 3, a shaping cover 4, a light shield 5, a reflector 6, and a PCB substrate 7. There are two receivers 2 and two transmitters 3, both of which are soldered to the PCB substrate 7. The two receivers 2 are spaced apart, and the two transmitters 3 are located on the left and right sides of the receivers 2. The shielding plate 1 and the shaping cover 4 are both made of metal. The shielding plate 1 and the shaping cover 4 are fixedly connected to form an radiation-resistant shielding cavity, and the shaping cover 4 is fixedly connected to the reflector 6 to form a reflective light cavity. The shaping cover 4 has two limiting holes 41 (circular holes that can fit the transmitter 3) and two shaping holes 42. The two shaping holes 42 are spaced apart, and the two limiting holes 41 are located on the left and right sides of the shaping hole 42. The PCB substrate 7 is fixedly connected in the anti-radiation shielding cavity. The two emitters 3 pass through the two limiting holes 41 respectively, and the light-emitting surface of the emitters 3 extends into the reflective light cavity. The two receivers 2 are respectively opposite the two shaping holes 42. The upper part of the light shielding plate 5 is provided with an elliptical assembly hole 52 for fixing the light shielding plate 5 to the moving part to be measured. The upper edge of the corresponding shaping cover 4 is provided with a first avoidance groove 45 for avoiding the screw tightening operation. The upper edge of the PCB substrate 7 is provided with a second avoidance groove 73 for avoiding the screw tightening operation. A light-transmitting hole 51 is provided in the middle and lower part of the light shielding plate 5. The light shielding plate 5 is inserted into the reflective light cavity and can move relative to the reflective light cavity. The reflected light can pass through the two shaping holes 42 through the light-transmitting hole 51 to reach the partial photosensitive surfaces of the two receivers 2. The anti-radiation shielding cavity formed by the fixed connection between the shielding plate 1 and the shaping cover 4 can protect the emitter 3 and the receiver 2 from the influence of radiation. The reflective light cavity formed by the fixed connection between the shaping cover 4 and the reflector 6 can obtain better light quality while blocking external light.

[0025] In some embodiments, a narrowband filter 9 is further provided within the reflective optical cavity. This filter is adhesively secured to the shaping cover 4, covering the two shaping holes 42. The center wavelength of the narrowband filter 9 matches the wavelength of the transmitter, and the bandwidth of the narrowband filter 9 is ±20 nm of the center wavelength. This filter can filter out the effects of external stray light on the receiver, thereby achieving higher-precision measurements.

[0026] In some embodiments, the shielding plate 1 and the shaping cover 4 are fixedly connected by gluing.

[0027] In some embodiments, the PCB substrate 7 is square, with notches 71 extending forward and backward at both upper corners, and first through-holes 72 extending forward and backward at both lower corners. The main body of the shaping cover 4 has second through-holes 43 extending forward and backward at both upper corners, and first threaded blind holes extending forward and backward at both lower corners. Third through-holes 44 extending vertically are provided on both supports at the lower portion of the shaping cover 4. Locking screw holes 61 are provided on both the left and right connecting posts of the reflector 6, and a second threaded blind hole extending vertically is provided at the bottom of the reflector 6. Two screws 8 are respectively passed through the two first through holes 72 and screwed into the two first blind holes. Two screws 8 are respectively passed through the two notches 71, through the two second through holes 43, and screwed into the two locking screw holes 61. Two screws 8 are respectively passed through the two third through holes 44 and screwed into the two second blind holes, thereby achieving a fixed connection between the PCB substrate 7 and the shaping cover 4, and a fixed connection between the shaping cover 4 and the reflector 6. As an example, the screws 8 are made of metal and are metal screws.

[0028] In some embodiments, the shielding plate 1 is made of tantalum metal, and the shaping cover 4 is made of aluminum alloy, which has low cost and good radiation resistance.

[0029] In some embodiments, the inner surface of the reflector 6 is a diffuse reflection surface, and the reflection light cavity is a diffuse reflection light cavity, thereby making the reflected light soft and uniform, thereby improving the sensor performance.

[0030] In some embodiments, the two receivers 2 are arranged symmetrically in the vertical direction, and the two transmitters 3 are symmetrically located on the left and right sides of the receiver 2. The two shaping holes 42 are arranged symmetrically in the vertical direction, and the two limiting holes 41 are symmetrically located on the left and right sides of the shaping hole 42. The shaping hole 42 is a square hole, and the light-transmitting hole 51 is a square hole. The width of the light-transmitting hole 51 in the vertical direction is greater than d1 and less than d2. Here, d1 represents the distance between the lower edge of the shaping hole 42 located above and the upper edge of the shaping hole 42 located below (i.e., the width of the interval between the two shaping holes 42 in the vertical direction), and d2 represents the distance between the upper edge of the shaping hole 42 located above and the lower edge of the shaping hole 42 located below. Since both the shaping hole 42 and the light-transmitting hole 51 are square holes, the lower edge of the shaping hole 42 located above and the upper edge of the shaping hole 42 located below are parallel to each other, and the zero position is centered, thereby avoiding amplification of signal nonlinearity. When the light shielding plate 5 moves, the area of ​​the light-sensitive surfaces of the two receivers 2 receiving the light signal changes, and the displacement or rotation angle of the light shielding plate is calculated based on the change in the area.

[0031] In the initial state (i.e., static state), the left and right edges of the light-transmitting aperture 51 are perpendicular to the upper and lower edges of the shaping aperture 42. The centerline of the light-transmitting aperture 51, the centerline of the shaping aperture 42 above it, and the centerline of the shaping aperture 42 below it are all parallel and coplanar. In this initial state, the photosensitive areas of the two receivers 2 (i.e., the areas of the receivers 2 that can receive reflected light) are equal, simplifying displacement and angle calculations.

[0032] During operation, the shading plate 5 has two movement modes.

[0033] The first motion pattern involves the light shield 5 moving vertically upward (or downward) driven by the moving component to be measured. When the light shield 5 moves vertically upward, the photosensitive area of ​​the upper receiver 2 increases, while the photosensitive area of ​​the lower receiver 2 decreases by the same amount. The signal representing the changed photosensitive area is then resolved (using a method known in the art) to determine the displacement of the light shield 5 due to its upward motion, and thus the displacement of the moving component to be measured. When the light shield 5 moves vertically downward, the photosensitive area of ​​the upper receiver 2 decreases, while the photosensitive area of ​​the lower receiver 2 increases by the same amount. The signal representing the changed photosensitive area is then resolved (using a method known in the art) to determine the displacement of the light shield 5 due to its downward motion, and thus the displacement of the moving component to be measured.

[0034] The second motion pattern involves the light shield 5 rotating with the moving component under test around its rotation point. When the rotation point lies on a line perpendicular to the geometric center of the light shield's light-transmitting aperture 51, the light shield 5 deflects the same amount in both the positive and negative directions. As the light shield 5 deflects around its rotation point, the photosensitive area of ​​one receiver 2 increases, while the photosensitive area of ​​the other receiver 2 decreases by the same amount. The signal from these changes in photosensitive area is then interpreted (using a conventional method) to determine the deflection angle of the light shield 5, and thus the deflection angle of the moving component under test.

[0035] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with this technical field within the technical scope disclosed in the present invention should be covered by the scope of protection of the present invention.

Claims

1. A radiation-resistant photoelectric sensor comprising a transmitter (3) and a receiver (2) soldered on a PCB substrate (7), characterized in that: The invention also includes a shielding plate (1), a shaping cover (4), a light shielding plate (5) and a reflector (6). The shielding plate (1) and the shaping cover (4) are both made of metal materials. The shielding plate (1) and the shaping cover (4) are fixedly connected to form an anti-radiation shielding cavity. The shaping cover (4) and the reflector (6) are fixedly connected to form a reflective light cavity. A limit hole (41) and a shaping hole (42) are provided on the shaping cover (4). The PCB substrate (7) is fixedly connected in the anti-radiation shielding cavity. The transmitter (3) passes through the limit hole (41) and the light-emitting surface extends into the reflective light cavity. The receiver (2) is directly opposite to the shaping hole (42). A light-transmitting hole (51) is provided on the light shielding plate (5). The light shielding plate (5) is inserted into the reflective light cavity and can move relative to the reflective light cavity. The reflected light can pass through the shaping hole (42) through the light-transmitting hole (51) and reach a part of the photosensitive surface of the receiver (2).

2. The radiation-resistant photoelectric sensor according to claim 1, wherein: It also includes a narrowband filter (9) located in the reflective light cavity, and the narrowband filter (9) is fixed on the shaping cover (4) to cover the shaping hole (42).

3. The radiation-resistant photoelectric sensor according to claim 1, wherein: The shielding plate (1) is made of tantalum metal, and the shaping cover (4) is made of aluminum alloy.

4. The radiation-resistant photoelectric sensor according to claim 1, wherein: The inner surface of the reflector (6) is a diffuse reflection surface, and the reflection light cavity is a diffuse reflection light cavity.

5. The radiation-resistant photoelectric sensor according to claim 1, wherein: There are two receivers (2), and the two receivers (2) are arranged at intervals in the upper and lower parts; there are two transmitters (3), and the two transmitters (3) are respectively located on the left and right sides of the receiver (2); there are two shaping holes (42), and the two shaping holes (42) are arranged at intervals in the upper and lower parts; there are two limiting holes (41), and the two limiting holes (41) are respectively located on the left and right sides of the shaping hole (42).

6. The radiation-resistant photoelectric sensor according to claim 5, characterized in that: The two receivers (2) are arranged symmetrically up and down, and the two transmitters (3) are symmetrically located on the left and right sides of the receiver (2); the two shaping holes (42) are arranged symmetrically up and down, and the two limiting holes (41) are symmetrically located on the left and right sides of the shaping hole (42).

7. The radiation-resistant photoelectric sensor according to claim 6, characterized in that: The shaping hole (42) is a square hole, and the light-transmitting hole (51) is a square hole. The width of the light-transmitting hole (51) in the up-down direction is greater than d1 and less than d2; wherein d1 represents the distance between the lower edge of the shaping hole (42) located above and the upper edge of the shaping hole (42) located below, and d2 represents the distance between the upper edge of the shaping hole (42) located above and the lower edge of the shaping hole (42) located below.

8. The radiation-resistant photoelectric sensor according to claim 7, characterized in that: In the initial state, the left and right edges of the light-transmitting hole (51) are perpendicular to the upper and lower edges of the shaping hole (42), and the center line of the light-transmitting hole (51), the center line of the shaping hole (42) located above, and the center line of the shaping hole (42) located below are all parallel to each other and located in the same plane.

9. The radiation-resistant photoelectric sensor according to any one of claims 1 to 8, characterized in that: An elliptical assembly hole (52) for fixing the shading plate (5) to the moving part to be measured is provided at the upper end of the shading plate (5), a first avoidance groove (45) is provided on the shaping cover (4), and a second avoidance groove (73) is provided on the PCB substrate (7).

10. The radiation-resistant photoelectric sensor according to claim 9, characterized in that: The shielding plate (1) and the shaping cover (4) are fixedly connected by gluing; The PCB substrate (7) is square, and its two upper corners are provided with notches (71) extending forward and backward, and its two lower corners are provided with first through holes (72) extending forward and backward; the two upper corners of the main body of the shaping cover (4) are provided with second through holes (43) extending forward and backward, and the two lower corners of the main body of the shaping cover (4) are provided with first blind holes extending forward and backward and having threads, and the two supports at the lower part of the shaping cover (4) are provided with third through holes (44) extending upward and downward; the left connecting column and the right connecting column of the reflector (6) are provided with locking screw holes (61), and the bottom of the reflector (6) is provided with a second blind hole extending upward and downward and having threads; Two screws (8) pass through the two first through holes (72) and are screwed to the two first blind holes; two screws (8) pass through the two notches (71), pass through the two second through holes (43), and are screwed to the two locking screw holes (61); two screws (8) pass through the two third through holes (44) and are screwed to the two second blind holes.

Images