Small laser range finder

Abstract

The utility model discloses a small laser range finder relates to laser ranging technical field, wherein, small laser range finder includes frame, and frame includes integral type connection's emission lens barrel and receiving lens barrel, and laser emission subassembly and circuit control subassembly all are arranged around the circumferential and axial setting of receiving lens barrel, and circuit control subassembly includes photoelectric conversion circuit, cross group amplification circuit and post stage amplification circuit that are electrically connected in proper order, and photoelectric conversion circuit includes avalanche diode, and avalanche diode is used to convert light signal into current signal, greatly improve the space utilization, significantly reduce the volume and structure size of whole machine, and integral type frame design avoids assembly error, adopts the avalanche diode without post stage amplification as photoelectric conversion core element, and signal processing is carried out in combination with cross group amplification circuit and post stage amplification circuit, while guaranteeing detection sensitivity, effectively reduce the space and cost of occupation, realize whole machine light weight.

Description

Technical Field

[0001] This utility model relates to the field of laser ranging technology, and in particular to a small laser ranging device. Background Technology

[0002] A laser rangefinder is an optoelectronic device that uses a laser beam to measure the distance to a target. It boasts advantages such as small size, light weight, high ranging accuracy, ease of operation, strong environmental adaptability, and high reliability, making it widely used in military, surveying, construction, and transportation fields. Especially in modern optoelectronic observation and aiming equipment and systems, the laser rangefinder, as a core ranging module, needs to be highly integrated with the overall system, placing higher demands on its miniaturization and weight reduction.

[0003] Currently, with the development of optoelectronic systems towards miniaturization and integration, the structural size and weight of laser rangefinders have become important factors limiting their application range. Traditional laser rangefinders typically adopt a separate layout in their structural design, with each functional module (such as the transmitting module, receiving module, control circuit, etc.) arranged independently. This results in a complex overall structure, low space utilization, and a large weight, making it difficult to meet the lightweight requirements of modern high-precision optoelectronic systems. In terms of optoelectronic detection, traditional laser rangefinders mostly use avalanche photodiodes with built-in post-amplification as echo signal detectors. Although this solution has strong anti-interference capabilities and high sensitivity, its large size and high cost are not conducive to the miniaturization design of the entire machine. Utility Model Content

[0004] The main purpose of this invention is to propose a small laser rangefinder, which aims to reduce the size and weight of the rangefinder.

[0005] To achieve the above objectives, the present invention proposes a small laser rangefinder, comprising: A frame, the frame including an integrally connected transmitting lens tube and receiving lens tube; Both the laser emitting component and the circuit control component are arranged around the receiving lens tube in the circumferential and axial directions; The circuit control assembly includes a photoelectric conversion circuit, a cross-group amplifier circuit, and a subsequent amplifier circuit that are connected in sequence. The photoelectric conversion circuit includes an avalanche diode, which is used to convert optical signals into current signals.

[0006] In one embodiment, the cross-group amplifier circuit is used to convert the current signal generated by the avalanche diode into a voltage signal and amplify it initially; The subsequent amplifier circuit is used to receive the voltage signal output by the cross-group amplifier circuit and amplify it a second time.

[0007] In one embodiment, the laser emitting assembly includes a laser emitter; The frame is equipped with a mounting platform located at the incident end of the emitting lens tube. The mounting platform is provided with a first connecting hole for mounting and fixing the laser emitter.

[0008] In one embodiment, the laser emitting assembly further includes a dust cover, which is fixedly connected to the frame; The dust cover has a U-shaped cross-section and is used to cover the part where the laser emitter and the emitting lens tube are connected.

[0009] In one embodiment, the miniature laser rangefinder further includes a receiving lens assembly, which includes a convex lens, a concave lens, and a narrowband filter; The convex lens, the concave lens, and the narrowband filter are sequentially disposed inside the receiving lens barrel.

[0010] In one embodiment, the frame is provided with a plurality of connecting posts, the ends of the plurality of connecting posts located away from the frame are located on the same plane, and the connecting posts are provided with a second connecting hole for mounting the circuit control component.

[0011] In one embodiment, the circuit control assembly includes a main control circuit board and a drive circuit board, which are respectively located on opposite sides of the receiving lens barrel in the circumferential direction, and both the main control circuit board and the drive circuit board are fixed to the frame through the connecting post.

[0012] In one embodiment, the circuit control assembly further includes an amplification circuit board, which is disposed on the side of the receiving lens tube away from the incident end and is fixedly connected to the receiving lens tube.

[0013] In one embodiment, the circuit control assembly further includes a beam expander assembly disposed inside the emitting lens tube for beam expansion of the laser emitted by the laser emitter.

[0014] In one embodiment, the frame is made of aluminum alloy.

[0015] The technical solution of this utility model integrates the transmitting and receiving lenses into a single unit, and integrates the laser emitting assembly and the circuit control assembly around the receiving lens in both circumferential and axial directions. This greatly improves space utilization and overcomes the shortcomings of traditional separate layouts, which are complex and occupy a large amount of space. It significantly reduces the overall size and structural dimensions of the device. The integrated frame design avoids assembly errors and improves the coaxiality and stability of the transmitting and receiving optical paths. At the same time, the overall structural rigidity and resistance to vibration and impact are enhanced, making it more suitable for harsh environments such as airborne systems. Furthermore, by using the avalanche diode without post-amplification as the core component for photoelectric conversion, and combining it with the cross-group amplifier circuit and the post-amplification circuit for signal processing, the space and cost occupied by the traditional avalanche diode with built-in post-amplification are effectively reduced while ensuring detection sensitivity, thus achieving overall lightweight design. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a structure of an embodiment of the small laser rangefinder provided by this utility model; Figure 2 This is a schematic diagram of the frame structure; Figure 3 A schematic diagram of the assembly structure of the small laser rangefinder provided by this utility model; Figure 4 A cross-sectional view of the small laser rangefinder provided by this utility model.

[0018] Explanation of icon numbers: 1. Frame; 11. Transmitting lens tube; 12. Receiving lens tube; 13. Mounting platform; 131. First connecting hole; 14. Connecting post; 141. Second connecting hole; 2. Laser emitting assembly; 21. Laser emitter; 22. Dust cover; 3. Circuit control assembly; 31. Main control circuit board; 32. Driver circuit board; 33. Amplification circuit board; 34. Avalanche diode; 4. Receiving lens assembly; 41. Convex lens; 42. Concave lens; 43. Narrowband filter; 44. First housing; 51. Second housing.

[0019] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0021] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0023] A laser rangefinder is an optoelectronic device that uses a laser beam to measure the distance to a target. It boasts advantages such as small size, light weight, high ranging accuracy, ease of operation, strong environmental adaptability, and high reliability, making it widely used in military, surveying, construction, and transportation fields. Especially in modern optoelectronic observation and aiming equipment and systems, the laser rangefinder, as a core ranging module, needs to be highly integrated with the overall system, placing higher demands on its miniaturization and weight reduction.

[0024] Currently, with the development of optoelectronic systems towards miniaturization and integration, the structural size and weight of laser rangefinders have become important factors limiting their application range. Traditional laser rangefinders typically adopt a separate layout in their structural design, with each functional module (such as the transmitting module, receiving module, control circuit, etc.) arranged independently. This results in a complex overall structure, low space utilization, and a large weight, making it difficult to meet the lightweight requirements of modern high-precision optoelectronic systems. In terms of optoelectronic detection, traditional laser rangefinders mostly use avalanche photodiodes with built-in post-amplification as echo signal detectors. Although this solution has strong anti-interference capabilities and high sensitivity, its large size and high cost are not conducive to the miniaturization design of the entire machine.

[0025] This utility model proposes a small laser rangefinder.

[0026] Please see Figures 1 to 4 In one embodiment of this utility model, the small laser rangefinder includes: The frame 1 includes an integrally connected transmitting lens tube 11 and receiving lens tube 12; Both the laser emitting component 2 and the circuit control component 3 are arranged around the receiving lens tube 12 in the circumferential and axial directions; The circuit control component 3 includes a photoelectric conversion circuit, a cross-group amplifier circuit, and a subsequent amplifier circuit that are connected in sequence. The photoelectric conversion circuit includes an avalanche diode 34, which is used to convert optical signals into current signals. The technical solution of this utility model connects the transmitting lens tube 11 and the receiving lens tube 12 in one piece, and integrates the laser emitting component 2 and the circuit control component 3 around the receiving lens tube 12 in both circumferential and axial directions. This greatly improves space utilization and overcomes the defects of traditional separate layout structures that are complex and occupy a large amount of space. It significantly reduces the volume and structural size of the whole machine. The integrated frame 1 design avoids assembly errors and improves the coaxiality and stability of the transmitting and receiving optical paths. At the same time, the overall structural rigidity and resistance to vibration and impact are enhanced, making it more suitable for harsh environments such as airborne. Furthermore, the avalanche diode 34 without post-amplification is used as the core component for photoelectric conversion. It is combined with the cross-group amplifier circuit and the post-amplification circuit for signal processing. While ensuring detection sensitivity, it effectively reduces the space and cost occupied by the traditional avalanche diode 34 with built-in post-amplification, achieving overall lightweight design.

[0027] It should be noted that the maximum diameter of traditional avalanche diodes with built-in amplification stage is usually 15.2mm-15.5mm, while the maximum diameter of the avalanche diode 34 without amplification stage used in this solution is 5.3mm-5.5mm. Compared with avalanche diodes with amplification stage, it is smaller, lighter, and lower in cost.

[0028] In some implementations, the main chip of the cross-group amplifier circuit is an OPA857IRGTR in a VQFN-16 package; the subsequent amplifier circuit is composed of two cascaded chips of the same model, with the main chip being an OPA695IDGKT in a VSSOP-8 package. The two stages are AC-coupled to further reduce size and weight while maintaining bandwidth.

[0029] Optionally, the cross-group amplifier circuit is used to convert the current signal generated by the avalanche diode 34 into a voltage signal and amplify it initially; The subsequent amplifier circuit is used to receive the voltage signal output by the cross-group amplifier circuit and amplify it a second time.

[0030] It should be noted that the cross-group amplifier circuit is used to convert the weak current signal generated by the avalanche diode 34 into a voltage signal and perform preliminary amplification, effectively improving the signal-to-noise ratio and laying a good foundation for subsequent processing. The subsequent amplifier circuit then performs secondary gain on the pre-amplified voltage signal to ensure that the echo signal strength is sufficient to be accurately identified by the subsequent information processing unit, thereby ensuring the accuracy and reliability of long-distance ranging.

[0031] It is understandable that the cross-group amplifier circuit and the subsequent amplifier circuit satisfy the condition of using the avalanche diode 34 without subsequent amplification, thereby further reducing the body size.

[0032] like Figure 1 and Figure 2 As shown, the laser emitting assembly 2 includes a laser emitter 21; The frame 1 is provided with a mounting platform 13, which is located on the incident end side of the emitting lens tube 11. The mounting platform 13 is provided with a first connecting hole 131 for mounting and fixing the laser emitter 21.

[0033] It should be noted that by directly fixing the laser emitter 21 to the mounting platform 13 on the incident end side of the emitting optical tube 11 and using the first connecting hole 131 for installation, the relative positional accuracy between the laser emitter 21 and the emitting optical tube is ensured. This direct and stable connection method effectively reduces assembly errors and potential displacements caused by multiple connecting components or adapter structures in traditional designs, ensuring the long-term stability of the laser emission axis, thereby improving the collimation and ranging accuracy of the emitted laser.

[0034] Furthermore, the laser emitter 21 can be disassembled and installed separately. If the laser emitter 21 needs to be replaced or repaired, it can be quickly disassembled and installed and the original optical path reference can be easily restored, thus improving the maintainability of the product.

[0035] It should be noted that the mounting platform 13 is integrally connected to both lens barrels, providing robust mechanical support for the laser emitter 21, improving the stability of the laser emitter 21 under harsh mechanical environments such as vibration and impact, and avoiding structural resonance or displacement that may be caused by fixing the laser emitter 21 alone.

[0036] Optionally, the laser emitter 21 is connected to the mounting platform 13 via a connector, which is a bolt and threaded into the first connecting hole 131.

[0037] In some embodiments, there are multiple first connection holes 131, which are evenly distributed on the mounting platform 13 to ensure the stability of the laser emitter 21.

[0038] Optionally, the laser emitting assembly 2 further includes a dust cover 22, which is fixedly connected to the frame 1; The dust cover 22 has a U-shaped cross-section and is used to cover the part where the laser emitter 21 and the emitting lens tube 11 are connected.

[0039] It is understood that by using the dust cover 22 with a U-shaped cross section and fixing it to the frame 1, the optical connection between the laser emitter 21 and the emitting lens barrel 11 can be specifically covered, effectively preventing the intrusion and physical contact of pollutants such as dust, oil, and water vapor. This avoids laser energy attenuation, optical path deviation, or lens damage caused by pollution, thereby ensuring the stability and reliability of ranging in complex environments and extending the service life of the equipment.

[0040] Understandably, the portion where the laser emitter 21 and the emitting lens tube 11 are connected is located inside the dust cover 22, and one end of the opening of the dust cover 22 abuts against the frame 1, so as to cooperate with the frame 1 to cover the laser emitter 21 and the emitting lens tube 11.

[0041] like Figure 4 As shown, the small laser rangefinder also includes a receiving lens assembly 4, which includes a convex lens 41, a concave lens 42, and a narrowband filter 43. The convex lens 41, the concave lens 42, and the narrowband filter 43 are sequentially disposed inside the receiving lens barrel 12.

[0042] It should be noted that by reducing the number of lenses, the required mechanical fixing structure is reduced, directly reducing the diameter and length of the receiving lens tube 12. Furthermore, by reducing the number of lenses, the overall weight is reduced, achieving miniaturization and weight reduction of the entire device.

[0043] It is understood that the convex lens 41 and the concave lens 42 are beneficial for correcting aberrations and converging light, while the narrowband filter 43 can effectively suppress ambient stray light interference, together ensuring the reception quality and signal-to-noise ratio of the echo signal under complex lighting conditions.

[0044] In some embodiments, the receiving lens assembly 4 further includes a first housing 44, in which the convex lens 41 and the concave lens 42 can be pre-installed into the housing outside the receiving lens barrel 12, and then the first housing 44 can be installed into the receiving lens barrel 12, so as to reduce assembly difficulty and improve assembly efficiency.

[0045] like Figure 2 As shown, the frame 1 is provided with a plurality of connecting posts 14, the ends of the plurality of connecting posts 14 away from the frame 1 are located on the same plane, and the connecting posts 14 are provided with second connecting holes 141 for mounting the circuit control component 3.

[0046] It is understood that the ends of the multiple connecting posts 14 are located on the same plane, and the circuit control assembly 3 is fixed through the second connecting hole 141, providing a high-flatness and high-rigidity mounting reference for the circuit board. This avoids problems such as circuit board deformation, connector loosening, or component desoldering caused by uneven mounting surfaces or vibration, significantly improving the reliability and long-term operational stability of the circuit module under mechanical stress.

[0047] It is understood that the connecting post 14 extends away from the frame 1, so that there is a partial gap between the circuit control component 3 and the frame 1, in order to improve the heat dissipation effect.

[0048] It should be noted that the gap between the circuit control component 3 and the frame 1 is due to the difference in diameter between the transmitting lens tube 11 and the receiving lens tube 12, and is caused by the need to ensure that the circuit control component 3 has a good mounting surface.

[0049] It should be noted that the multiple sets of connecting posts 14 can form multiple mounting surfaces depending on the extension direction and extension length, so as to facilitate the installation of different components.

[0050] like Figure 3 As shown, the circuit control component 3 includes a main control circuit board 31 and a drive circuit board 32. The main control circuit board 31 and the drive circuit board 32 are respectively located on opposite sides of the receiving lens barrel 12 in the circumferential direction, and both the main control circuit board 31 and the drive circuit board 32 are installed and fixed to the frame 1 through the connecting post 14.

[0051] It is understandable that by arranging the main control circuit board 31 and the drive circuit board 32 on opposite sides of the receiving lens barrel 12, the annular space around the receiving lens barrel 12 is fully utilized, avoiding congestion on one side and ensuring symmetrical and balanced weight distribution of the entire device. This improves space utilization efficiency and achieves miniaturization and weight reduction of the entire device.

[0052] Furthermore, the driving circuit, which generates heat and may cause interference, is physically separated from the main control circuit that handles the core processing, effectively avoiding concentrated heat sources and mutual thermal and electromagnetic interference between circuits.

[0053] like Figure 4 As shown, the circuit control component 3 also includes an amplification circuit board 33, which is located on the side of the receiving lens tube 12 away from the incident end and is fixedly connected to the receiving lens tube 12.

[0054] It is understandable that the amplifying circuit board 33 makes full use of the axial space behind the receiving lens tube 12, avoiding the need to occupy other space. Secondly, the avalanche diode 34 is located on the side of the receiving lens tube 12 away from the incident end and partially extends into the inside of the receiving lens tube 12. The amplification circuit board 33 located there is closest to the avalanche diode 34, which shortens the transmission path of the weak photocurrent signal to the maximum extent and effectively reduces the signal attenuation and the introduction of external electromagnetic interference during the transmission process.

[0055] Optionally, the circuit control component 3 further includes a beam expander assembly, which is disposed inside the emitting lens tube 11 and is used to expand the beam of the laser emitted by the laser emitter 21.

[0056] In some embodiments, the second beam expander assembly further includes a second housing 51, which is used to pre-install each beam expander lens on the outside of the outer transmitting lens barrel 11. After installation, the second housing 51 is then inserted into the transmitting lens barrel 11 to complete the assembly and improve installation efficiency.

[0057] It should be noted that the beam expander assembly includes three lenses with a focal length of 15mm, which further reduces the length required for the emitting lens tube 11.

[0058] Optionally, the frame 1 is made of aluminum alloy.

[0059] Understandably, the aluminum alloy material allows the frame 1 to achieve a significant weight reduction while meeting the overall structural rigidity and strength requirements, enabling the overall weight of the machine to be controlled below 30 grams.

[0060] It should be noted that the maximum overall dimensions (length × width × height) of the machine are 44.8 mm × 21 mm × 30.3 mm, and the tolerance for each dimension is ±0.5 mm.

[0061] The above description is merely an exemplary embodiment of the present utility model and does not limit the scope of protection of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present utility model.

Claims

1. A small laser rangefinder, characterized in that, include: A frame, the frame including an integrally connected transmitting lens tube and receiving lens tube; Both the laser emitting component and the circuit control component are arranged around the receiving lens tube in the circumferential and axial directions; The circuit control assembly includes a photoelectric conversion circuit, a cross-group amplifier circuit, and a subsequent amplifier circuit that are connected in sequence. The photoelectric conversion circuit includes an avalanche diode, which is used to convert optical signals into current signals.

2. The miniature laser rangefinder as described in claim 1, characterized in that, The cross-group amplifier circuit is used to convert the current signal generated by the avalanche diode into a voltage signal and amplify it initially. The subsequent amplifier circuit is used to receive the voltage signal output by the cross-group amplifier circuit and amplify it a second time.

3. The miniature laser rangefinder as described in claim 1, characterized in that, The laser emitting assembly includes a laser emitter; The frame is equipped with a mounting platform located at the incident end of the emitting lens tube. The mounting platform is provided with a first connecting hole for mounting and fixing the laser emitter.

4. The miniature laser rangefinder as described in claim 3, characterized in that, The laser emitting assembly also includes a dust cover, which is fixedly connected to the frame. The dust cover has a U-shaped cross-section and is used to cover the part where the laser emitter and the emitting lens tube are connected.

5. The miniature laser rangefinder as described in claim 1, characterized in that, The small laser rangefinder also includes a receiving lens assembly, which includes a convex lens, a concave lens, and a narrowband filter. The convex lens, the concave lens, and the narrowband filter are sequentially disposed inside the receiving lens barrel.

6. The miniature laser rangefinder as described in claim 5, characterized in that, The frame is provided with multiple connecting posts, the ends of the multiple connecting posts away from the frame are located on the same plane, and the connecting posts are provided with second connecting holes for mounting the circuit control components.

7. The miniature laser rangefinder as described in claim 6, characterized in that, The circuit control assembly includes a main control circuit board and a drive circuit board. The main control circuit board and the drive circuit board are respectively located on opposite sides of the receiving lens barrel in the circumferential direction, and both the main control circuit board and the drive circuit board are fixed to the frame through the connecting column.

8. The miniature laser rangefinder as described in claim 5, characterized in that, The circuit control assembly also includes an amplification circuit board, which is located on the side of the receiving lens tube away from the incident end and is fixedly connected to the receiving lens tube.

9. The miniature laser rangefinder as described in claim 3, characterized in that, The circuit control assembly also includes a beam expander assembly, which is disposed inside the emitting lens tube and is used to expand the beam of the laser emitted by the laser emitter.

10. The miniature laser rangefinder as described in claim 1, characterized in that, The frame is made of aluminum alloy.

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