A laser range finder

Abstract

The application discloses a laser range finder, which comprises a first circuit board and a second circuit board arranged in parallel, a laser diode and a laser emission conditioning circuit arranged on the first circuit board, a photoelectric sensor and a photoelectric amplification conditioning circuit arranged on the second circuit board, a mirror support and a mirror, wherein the mirror is installed on the mirror support and can be adjusted in angle, and is used for guiding reflected light to the photoelectric sensor. The integrated and layered layout greatly compresses the overall structure size, lays a foundation for miniaturized design, and clearly divides the functions of components, thereby facilitating modular production and debugging.

Description

Technical Field

[0001] This application relates to the field of distance measurement, and more particularly to a laser rangefinder. Background Technology

[0002] A laser rangefinder is a device that uses laser light to measure the distance to a target. Currently, most laser rangefinders use laser phase ranging. Common laser rangefinders are larger than 45mm (length) x 16mm (width) x 10mm (height). This large module size is inconvenient for portability or product integration, while a smaller size can cause crosstalk in the transceiver circuitry, affecting the ranging range and accuracy.

[0003] Therefore, based on the above solutions, the existing technology still needs improvement. Summary of the Invention

[0004] The purpose of this application is to reduce the size of the rangefinder without affecting the measurement accuracy.

[0005] The above-mentioned technical objective of this application is achieved through the following technical solution: A laser rangefinder, comprising: A first circuit board and a second circuit board arranged in parallel; The first circuit board is equipped with a laser diode and a laser emission conditioning circuit; The second circuit board is equipped with a photoelectric sensor and a photoelectric amplification and conditioning circuit; A reflector bracket and a reflector, wherein the reflector is mounted on the reflector bracket and the angle of the reflector is adjustable to guide the reflected light to the photoelectric sensor.

[0006] The above-mentioned solution in this application, by setting up a first circuit board and a second circuit board in parallel, integrates a laser diode and a laser emission conditioning circuit on the first circuit board, and a photoelectric sensor and a photoelectric amplification conditioning circuit on the second circuit board. It also includes a reflector bracket and an adjustable-angle reflector to guide the reflected light to the photoelectric sensor. Firstly, the parallel arrangement of the two circuit boards achieves physical separation of the transmitting and receiving circuits, reducing electromagnetic crosstalk between the laser emission conditioning circuit (including high-frequency modulation signals) and the photoelectric amplification conditioning circuit (processing weak light signals) from a spatial layout perspective, thus improving the signal-to-noise ratio of signal processing. Secondly, the adjustable reflector angle design can accurately calibrate the propagation path of the reflected light, ensuring that the reflected light accurately enters the photosensitive area of ​​the photoelectric sensor, avoiding signal loss or attenuation due to optical path deviation. Finally, this integrated layered layout significantly compresses the overall structural size, laying the foundation for miniaturized design, while the clear functional partitioning of each component facilitates modular production and debugging.

[0007] Optionally, the laser rangefinder further includes: A laser receiving collimating lens is used to receive the reflected light after diffuse reflection, and the laser receiving collimating lens is located at the front end of the transmitting mirror.

[0008] The above-mentioned solution in this application, by adding a laser receiving collimating lens and placing it at the front end of the transmitting mirror to receive the reflected light after diffuse reflection, addresses the issue that the laser beam diverges after diffuse reflection from the target, resulting in dispersed energy and chaotic propagation directions. The laser receiving collimating lens can focus and collimate these divergent reflected lights, converging the dispersed light energy into a concentrated beam, significantly improving the intensity of the light signal received by the photoelectric sensor. At the same time, the collimating lens can filter out some of the scattered stray light generated by diffuse reflection, reducing interference from light rays from non-target directions and improving the purity of the received signal. Furthermore, the layout of placing it at the front end of the transmitting mirror allows the receiving optical path and the transmitting optical path to work together at the front end, avoiding structural redundancy caused by optical path intersections, further optimizing space utilization, adapting to the overall miniaturized design, and indirectly improving the rangefinder's ability to detect distant targets.

[0009] Optionally, in the laser rangefinder, the reflector is connected to the reflector bracket by a plurality of screws.

[0010] The aforementioned solution in this application utilizes a multi-screw connection method to achieve stable fixation of the reflector on the bracket, preventing positional displacement of the reflector due to environmental factors such as vibration and temperature changes, thus ensuring optical path stability. Simultaneously, by adjusting the tightness of different screws, the angle of the reflector can be precisely adjusted in two dimensions (such as pitch and yaw angles), thereby accurately controlling the propagation direction of the reflected light and ensuring precise alignment with the photosensitive surface of the photoelectric sensor. Furthermore, the screw connection structure is simple, low-cost, and the adjustment process is reversible, facilitating optical path calibration during production and debugging phases. It also provides convenience for subsequent maintenance and accuracy calibration, ensuring the long-term accuracy and stability of the rangefinder.

[0011] Optionally, in the laser rangefinder, the angle between the reflector and the first circuit board and the second circuit board is 45 degrees.

[0012] The aforementioned solution in this application utilizes a 45-degree angle design, enabling the reflector to vertically redirect horizontally propagating reflected light (focused by the receiving collimating lens) towards the photoelectric sensor (which is typically perpendicular to the incident direction of the reflected light due to the parallel arrangement of the circuit boards). This achieves efficient redirection of the optical path, avoids intersections between parallel circuit boards, significantly reduces the space required for the optical path, and adapts to a miniaturized overall layout. Furthermore, the 45-degree angle is one of the optimal angles for light reflection redirection, minimizing light energy loss during reflection and ensuring the intensity of the reflected light. In addition, the fixed angle provides a reference for the installation and adjustment of the reflector, facilitating standardized calibration during production, ensuring optical path consistency between different products, and improving the stability of mass production.

[0013] Optionally, in the laser rangefinder, the emitting optical path of the laser diode is parallel to the receiving optical path of the photoelectric sensor.

[0014] The parallel optical path design of the above-mentioned solution fundamentally avoids cross-interference between the transmitting and receiving optical paths, reducing the saturation or signal distortion of the photoelectric sensor caused by the direct incident of strong light from laser emission onto the receiving end. Simultaneously, the parallel optical path ensures that the transmitted and received light maintain consistent directional characteristics during propagation. When the rangefinder experiences slight tilt or vibration, the offset trends of the transmitted and received light are consistent, and the adjustment of the reflector can simultaneously adapt to both changes, reducing the complexity of optical path calibration. Furthermore, the parallel optical path and the parallel-arranged dual circuit boards form a structural synergy, matching the circuit layout with the optical path direction, further optimizing internal space utilization, providing key support for achieving miniaturization, and ensuring the stability of signal transmission during ranging.

[0015] Optionally, the laser rangefinder further includes a laser emitting module, which is used to reflect and focus the light source to emit a parallel light source perpendicular to the light path of the laser diode.

[0016] The aforementioned solution of this application utilizes the reflection and focusing functions of the laser emission module to convert the divergent light emitted by the laser diode into a highly parallel beam, reducing energy diffusion during propagation and significantly enhancing the long-distance propagation capability of the laser, thus extending the ranging range. The design perpendicular to the original emission optical path allows the emission optical path and the circuit board to form a vertical layout, which is compatible with the parallel dual circuit board structure, avoiding spatial conflicts between the optical path and the circuit in the plane and further compressing the overall volume. At the same time, the emission of the parallel light source ensures that the laser energy distribution on the target is uniform, and the reflected light signal has higher stability, providing a more reliable original signal for subsequent phase difference measurement and indirectly improving the ranging accuracy.

[0017] Optionally, in the laser rangefinder, the photoelectric sensor is an APD, PD, PIN, MPPC, or SPAD photoelectric conversion device.

[0018] The above-mentioned solution in this application, by selecting these devices, ensures that the receiver can efficiently and accurately convert optical signals into electrical signals, providing high-quality raw data for subsequent signal amplification and phase difference calculation, thereby ensuring the stability of ranging accuracy and range.

[0019] In summary, this application has at least one of the following beneficial effects: 1. A technical solution that integrates a laser diode and laser emission conditioning circuit on the first circuit board and a photoelectric sensor and photoelectric amplification conditioning circuit on the second circuit board, and configures a reflector bracket and an adjustable-angle reflector to guide the reflected light to the photoelectric sensor, achieves several advantages. First, the parallel arrangement of the two circuit boards physically separates the transmitting and receiving circuits, reducing electromagnetic crosstalk between the laser emission conditioning circuit (including high-frequency modulation signals) and the photoelectric amplification conditioning circuit (processing weak light signals) from a spatial layout perspective, thus improving the signal-to-noise ratio of signal processing. Second, the adjustable reflector angle design allows for precise calibration of the propagation path of the reflected light, ensuring that the reflected light accurately hits the photosensitive area of ​​the photoelectric sensor, avoiding signal loss or attenuation due to optical path deviation. Finally, this integrated layered layout significantly reduces the overall structural size, laying the foundation for miniaturized design, while the clear functional partitioning of each component facilitates modular production and debugging. 2. A technical solution involving the addition of a laser receiving collimating lens, positioned at the front of the transmitting mirror, to receive diffusely reflected light. After diffuse reflection from the target, the laser beam diverges, its energy dispersed and its propagation direction chaotic. The laser receiving collimating lens can focus and collimate these divergent reflected lights, converging the dispersed light energy into a concentrated beam, significantly improving the intensity of the light signal received by the photoelectric sensor. Simultaneously, the collimating lens can filter out some of the scattered stray light generated by diffuse reflection, reducing interference from light rays from non-target directions and improving the purity of the received signal. Furthermore, its placement at the front of the transmitting mirror allows the receiving and transmitting optical paths to work in tandem at the front, avoiding structural redundancy caused by optical path intersections, further optimizing space utilization, adapting to overall miniaturization design, and indirectly improving the rangefinder's ability to detect distant targets. 3. The multiple screw connection method ensures stable fixation of the reflector on the bracket, preventing positional displacement of the reflector due to environmental factors such as vibration and temperature changes, thus guaranteeing optical path stability. Simultaneously, by adjusting the tightness of different screws, the angle of the reflector can be precisely adjusted in two dimensions (such as pitch and yaw angles), thereby accurately controlling the propagation direction of the reflected light and ensuring precise alignment with the photosensitive surface of the photoelectric sensor. Furthermore, the screw connection structure is simple, low-cost, and the adjustment process is reversible, facilitating optical path calibration during production and debugging phases. It also provides convenience for subsequent maintenance and accuracy calibration, ensuring the long-term accuracy and stability of the rangefinder. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the laser rangefinder of this application.

[0021] Figure 2 This is a side cross-sectional view of the laser rangefinder of this application.

[0022] Figure 3 This is a top view of the laser rangefinder of this application.

[0023] Reference numerals: 1. First circuit board; 2. Second circuit board; 201. Photoelectric sensor; 3. Reflector bracket; 4. Reflector; 5. Laser emitting module; 6. VSCEL emitting module. Detailed Implementation

[0024] The present application will be further described in detail below with reference to the accompanying drawings.

[0025] This application discloses a laser rangefinder, see embodiments thereof. Figures 1-3 This includes: A first circuit board 1 and a second circuit board 2 are arranged in parallel. The first circuit board 1 is equipped with a laser diode and a laser emission conditioning circuit; The second circuit board 2 is equipped with a photoelectric sensor 201 and a photoelectric amplification and conditioning circuit; The reflector bracket 3 and the reflector 4 are provided. The reflector 4 is mounted on the reflector bracket 3 and its angle is adjustable. It is used to guide the reflected light to the photoelectric sensor 201.

[0026] In this embodiment, by setting up a first circuit board 1 and a second circuit board 2 arranged in parallel, a laser diode and a laser emission conditioning circuit for driving the diode and generating a periodic modulation signal are integrated on the first circuit board 1, and a photoelectric sensor 201 and a photoelectric amplification conditioning circuit for amplifying and filtering weak electrical signals are integrated on the second circuit board 2. A reflector bracket 3 is fixed to the second circuit board 2, and a reflector 4, whose angle can be adjusted (e.g., pitch angle, yaw angle), is mounted on the bracket to achieve a technical solution of precisely guiding the reflected light to the photoelectric sensor 201. This achieves the following technical effects: First, the physical isolation design of the parallel dual circuit boards cuts off the electromagnetic coupling path between the high-frequency modulation signal at the transmitting end and the weak electrical signal at the receiving end from a spatial dimension (electromagnetic radiation is strong). The laser rangefinder attenuates with distance, and the absence of intersecting traces further reduces interference, significantly improving the signal-to-noise ratio of the received signal and providing a stable signal foundation for accurate phase difference measurement, avoiding ranging errors caused by crosstalk. Secondly, the adjustable-angle reflector 4, based on the law of light reflection, can compensate for the propagation direction deviation of the diffuse reflected light from the target and module assembly errors in real time, ensuring that the reflected light is accurately incident on the photosensitive area of ​​the photoelectric sensor 201, avoiding light energy loss due to optical path offset, and ensuring the efficiency of optical signal reception. Finally, the layered circuit layout replaces the traditional horizontal expansion with vertical space multiplexing, greatly compressing the overall structural size, while the functional partitions are clearly defined (independent transmitting and receiving circuits), facilitating modular production and subsequent debugging, laying a core foundation for adapting the laser rangefinder to small device integration scenarios.

[0027] In some possible embodiments of this application, the laser rangefinder further includes: A laser receiving collimating lens is used to receive the reflected light after diffuse reflection, and the laser receiving collimating lens is located at the front end of the transmitting lens.

[0028] In this embodiment, by adding a laser receiving collimating lens, specifically defining the function of this collimating lens as receiving the reflected light after diffuse reflection from the target, and placing it at the front end of the transmitting mirror (on the same side as the transmitting mirror, parallel to the central axis), the following technical effects are achieved: From an optical principle perspective, after diffuse reflection from the target, the laser light diverges, with its energy decreasing sharply with the propagation distance and its propagation direction becoming chaotic. The laser receiving collimating lens utilizes the refractive properties of a convex lens to converge the divergent reflected light into a concentrated beam, significantly improving the effective light signal intensity received by the photoelectric sensor 201 and solving the measurement blind zone problem caused by weak reflected light; simultaneously, the collimating lens only allows light propagating along the receiving optical axis. The high-efficiency light transmission of the optical path filters out stray ambient light (such as natural light and artificial light of non-target wavelengths), reducing interference from stray light on the photoelectric sensor 201, further improving the purity of the received signal, and reducing measurement errors caused by stray light superposition. In addition, the layout of placing the receiving collimating lens at the front end of the transmitting lens makes the transmitting and receiving optical paths form a parallel structure at the front end of the module, avoiding the crossing of optical paths inside the module, greatly optimizing the internal space utilization, and forming a synergy with the layered layout of the parallel dual circuit boards (first circuit board 1 and second circuit board 2), indirectly improving the rangefinder's ability to detect distant targets (the converged light signal can support effective reception at a greater distance).

[0029] In some possible embodiments of this application, the laser rangefinder is described in which the reflector 4 is connected to the reflector bracket 3 by a plurality of screws.

[0030] In this embodiment, by using multiple micro-screws (such as in a symmetrical or isosceles triangular arrangement) to connect the reflector 4 to the reflector bracket 3, and by using flexible gaskets (such as silicone gaskets) between the screws and the edge of the reflector 4 to achieve non-hard contact, the following technical effects are achieved: From the perspective of structural stability, the symmetrical arrangement of multiple screws can form a uniform fixing force on the reflector 4, effectively resisting the positional displacement of the reflector 4 caused by environmental factors such as vibration and temperature changes (such as material deformation under high and low temperature working environments), ensuring that the optical path remains stable for a long time, and avoiding fluctuations in ranging accuracy caused by loosening of the reflector 4; From the perspective of adjustment accuracy, by using differential... By rotating the screws in different positions (e.g., tightening the top screw and loosening the side screws), the reflector 4 can be driven around the support point of the bracket to achieve precise two-dimensional adjustment of the pitch and yaw angles. Based on the principle of mechanical balance, it can accurately control the propagation direction of the reflected light, ensuring that it is completely aligned with the photosensitive surface of the photoelectric sensor 201, thereby maximizing the efficiency of light signal reception. In addition, the screw connection structure has the advantages of simple design and low manufacturing cost, and the adjustment process is reversible (it can be adjusted without disassembling the module). This not only facilitates optical path calibration during the production and debugging stage, but also provides convenience for accuracy maintenance during subsequent use, ensuring the accuracy and stability of the rangefinder from the perspective of long-term use.

[0031] In some possible embodiments of this application, the laser rangefinder is described in which the reflector 4 forms a 45-degree angle with the first circuit board 1 and the second circuit board 2.

[0032] In this embodiment, by limiting the angle between the reflector 4 and the parallel-arranged first circuit board 1 and second circuit board 2 to 45 degrees, and ensuring the installation accuracy of this angle through the positioning structure of the reflector bracket 3, the following technical effects are achieved: Based on the law of reflection of light (the angle of reflection equals the angle of incidence), the 45-degree angle allows the reflected light (after being focused by the receiving collimating lens) propagating parallel to the circuit board direction to be redirected vertically, precisely guiding it to the photoelectric sensor 201 mounted on the circuit board (because the circuit boards are stacked in parallel, the photosensitive surface of the photoelectric sensor 201 is usually perpendicular to the horizontal light path). This redirection design avoids spatial conflict between the receiving light path and the parallel circuit boards, significantly reducing the space required for the light path to be reflected. The internal space required for the optical path directly adapts to the miniaturized layout requirements of laser rangefinders. Simultaneously, 45 degrees is one of the optimal angles for light reflection and redirection. At this angle, the reflector 4 achieves the highest reflection efficiency for the target laser wavelength, minimizing light energy loss during reflection and ensuring sufficient intensity of the reflected light for effective reception by the photoelectric sensor 201. This avoids shortening the ranging range due to reflection loss. Furthermore, the fixed 45-degree angle provides a clear reference parameter for the installation of the reflector 4, facilitating standardized installation during production. This reduces optical path deviations between different products, significantly improves consistency in mass production, and minimizes product performance differences caused by installation errors.

[0033] In some possible embodiments of this application, the laser rangefinder is wherein the laser diode emitting optical path is parallel to the photoelectric sensor 201 receiving optical path.

[0034] In this embodiment, by keeping the emitting optical path of the laser diode and the receiving optical path of the photoelectric sensor 201 parallel (the central axes of the two optical paths are parallel, without intersection or tilt), the following technical effects are achieved: First, the parallel optical path design fundamentally avoids cross-interference between the emitting and receiving optical paths, effectively preventing strong light from directly incident on the receiving end during laser emission (a problem prone to occur in traditional cross-optical paths), thereby avoiding signal saturation or distortion of the photoelectric sensor 201 due to strong light irradiation, and ensuring the authenticity and accuracy of the received signal; Second, when the rangefinder experiences a slight positional shift due to external vibration or tilt, the offset trend of the emitting and receiving optical paths is completely eliminated. The parallel optical path achieves full consistency (synchronization), requiring only the adjustment of the angle of the reflector 4 to simultaneously adapt to the offset of the two optical paths without separate calibration, significantly reducing the complexity and difficulty of optical path calibration. In addition, the parallel optical path and the parallel-set dual circuit boards (first circuit board 1 and second circuit board 2) form a structural synergy—the optical path direction matches the circuit board layout, which can further optimize the internal space allocation of the module, reduce redundant structures, and provide key support for achieving a miniaturized size of 27mm×13.8mm×10mm. At the same time, the stability of the parallel optical path also ensures the continuity and reliability of signal transmission during ranging, avoiding measurement interruptions caused by optical path fluctuations.

[0035] In some possible embodiments of this application, the laser rangefinder further includes a laser emitting module 5, which is used to reflect and focus the light source to emit a parallel light source perpendicular to the light path of the laser diode.

[0036] In this embodiment, by adding a laser emitting module 5, it is clarified that this module has the technical solution to reflect and focus the original divergent light emitted by the laser diode, and finally emit a parallel light source perpendicular to the original emission path of the laser diode, achieving the following technical effects: From the perspective of light propagation characteristics, the light originally emitted by the laser diode is divergent light, and its energy easily diffuses with the propagation distance. The laser emitting module 5 converts the divergent light into parallel light through a focusing structure (such as a convex lens), which can significantly reduce the energy attenuation of light during propagation, extend the effective propagation distance of the laser, and thus improve the maximum ranging range of the rangefinder; secondly, the direction of the parallel light source emitted by the module is perpendicular to the laser diode. The original light emission path, with its vertical layout, can be adapted to the layered structure of the parallel dual circuit boards (first circuit board 1, second circuit board 2). The original light emission path extends along the plane of the circuit board, and the parallel light after being perpendicular can propagate along the direction perpendicular to the circuit board, avoiding spatial conflicts between the light path and the circuit in the plane, further compressing the overall volume of the module and enhancing the miniaturization advantage. In addition, when the parallel light source illuminates the target surface, the light energy is evenly distributed, and there will be no local energy that is too strong or too weak due to divergence. This makes the light signal intensity after diffuse reflection from the target more stable, providing a more reliable original signal for subsequent phase difference measurement, indirectly reducing the ranging error caused by fluctuations in the reflected signal, and improving the overall measurement accuracy.

[0037] In some possible embodiments of the laser rangefinder described in this application, the photoelectric sensor 201 is an APD, PD, PIN, MPPC, or SPAD photoelectric conversion device.

[0038] In this embodiment, by limiting the photoelectric sensor 201 to photoelectric conversion devices such as APD (Avalanche photodiode), PD (photodiode), PIN (PIN junction photodiode), MPPC (multi-pixel photon counter), and SPAD (single-photon avalanche diode), the following technical effects are achieved: From the perspective of photoelectric conversion principle, these devices all possess efficient photo-to-electric signal conversion capabilities, accurately converting received optical signals into processable electrical signals, providing high-quality raw data for subsequent amplification, filtering, and phase detection; among them, APD and SPAD have extremely high photoelectric gain and sensitivity, and based on the avalanche multiplication effect, they can effectively detect weak light signals reflected from distant targets (such as low-light signals at a distance of 100 meters). The reflective properties of the target significantly enhance the rangefinder's ability to detect long-distance or low-reflectivity targets. PD and PIN have the characteristics of fast response speed and low noise, and can quickly capture changes in high-frequency modulated light signals (such as MHz-level modulated signals), perfectly matching the processing requirements of rapidly changing light signals in laser phase ranging, and avoiding phase difference measurement deviations caused by response lag. MPPC has the advantages of high sensitivity and multi-pixel detection, and reduces random errors of single-point detection through multi-pixel parallel detection, further improving signal stability. By limiting these devices, it is ensured that the receiver can be adapted to the optimal sensor according to different ranging scenarios (such as high precision at close range and weak signal at long range), ensuring the stability of ranging accuracy and range from the source.

[0039] In this embodiment, the laser rangefinder is an integrated miniature ranging device, whose core consists of a control unit, a transmitting unit, a receiving unit, and an optical adjustment structure. High-precision ranging and miniaturized integration are achieved through modular design. Its core components and functions are as follows: Laser emitting module 5 As an external optical path laser emitting device, it is used to emit parallel laser light sources and mainly includes a laser diode, an optical collimating lens, a laser diode mount, and an optical collimating lens mount. By adjusting the relative positions of the laser diode and the optical collimating lens, the emitted light is ensured to be parallel. Positioning is achieved by relying on the structural precision of the module body bracket, reducing the need for optical path debugging. Only the focal length and direction adjustment at the receiving end are required to complete the overall optical path calibration.

[0040] Laser receiving collimator This collimating lens is used to receive the laser signal diffusely reflected from the target and focus it onto the photoelectric sensor 201. The collimating lens can be adjusted one-dimensionally along the receiving optical axis, and by changing the focal length, it ensures that the reflected light is precisely focused on the photosensitive area of ​​the photoelectric sensor 201, thereby improving the efficiency of light signal reception.

[0041] Photoelectric sensor 201 It employs photoelectric conversion devices such as APD (avalanche photodiode), PD (photodiode), PIN (PIN junction photodiode), MPPC (multi-pixel photon counter), and SPAD (single-photon avalanche diode) to efficiently convert the received optical signal into an electrical signal, providing raw data for subsequent signal processing.

[0042] Mirror bracket 3 The reflector 4 is fixed at a 45-degree angle in the receiving optical path and mounted at the fulcrum of the bracket and the optical body base. Two-dimensional adjustment (such as pitch angle and yaw angle) can be achieved by at least 3 screws, which can precisely control the propagation direction of the received light, ensure that the receiving optical path is parallel to the transmitting optical path, and achieve parallel separation of the receiving and transmitting optical paths to avoid mutual interference.

[0043] Circuit board assembly PCB1 (laser emitting circuit, i.e., first circuit board 1): integrates laser diode driving and conditioning circuit, laser diode, and preferably integrates digital circuits such as phase-locked loop (PLL) and microcontroller (MCU). Since the laser emitting unit is an active light-emitting component, its modulation circuit is prone to high-frequency radiation. Independent setting can reduce interference to the receiving circuit, and PCB1 (first circuit board 1) is directly connected to the laser emitting module 5.

[0044] PCB2 (laser receiving circuit, i.e., second circuit board 2): integrates photoelectric sensor 201 and photoelectric sensor 201 signal amplification circuit. Preferably, the receiving local oscillator signal conditioning circuit and photodiode bias voltage circuit are integrated on it to focus on the reception and processing of weak light signals and improve the signal-to-noise ratio.

[0045] The two circuit boards (the first circuit board 1 and the second circuit board 2) communicate with each other through a board-to-board connector. The pin pitch of the connector is less than 1.5mm to ensure a compact connection and stable communication.

[0046] Filter Located in the optical path between the receiving collimating lens and the photoelectric sensor 201, it is used to filter out wavelength signals other than the laser emission wavelength, reduce ambient stray light interference, and improve the purity of the received signal.

[0047] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A laser rangefinder, characterized in that, include: A first circuit board (1) and a second circuit board (2) are arranged in parallel; the first circuit board (1) is provided with a laser diode and a laser emission conditioning circuit; the second circuit board (2) is provided with a photoelectric sensor (201) and a photoelectric amplification conditioning circuit; a reflector bracket (3) and a reflector (4), the reflector (4) is mounted on the reflector bracket (3), and the angle of the reflector (4) can be adjusted to guide the reflected light to the photoelectric sensor (201).

2. The laser rangefinder according to claim 1, characterized in that, It also includes: a laser receiving collimator, used to receive the reflected light after diffuse reflection, wherein the laser receiving collimator is located at the front end of the transmitting mirror.

3. The laser rangefinder according to claim 1, characterized in that, The reflector (4) is connected to the reflector bracket (3) by a plurality of screws.

4. The laser rangefinder according to claim 1, characterized in that, The angle between the reflector (4) and the first circuit board (1) and the second circuit board (2) is 45 degrees.

5. The laser rangefinder according to claim 1, characterized in that, The laser diode's emitting optical path is parallel to the photoelectric sensor's (201) receiving optical path.

6. The laser rangefinder according to claim 5, characterized in that, It also includes a laser emitting module (5), which is used to reflect and focus the light source to emit a parallel light source perpendicular to the light path of the laser diode.

7. The laser rangefinder according to claim 1, characterized in that, The photoelectric sensor (201) is an APD, PD, PIN, MPPC, or SPAD photoelectric conversion device.

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