A laser range finder circuit and laser range finder

Abstract

This application relates to the technical field of laser ranging, and more particularly to a laser rangefinder circuit and a laser rangefinder. It includes: a first output terminal of a main control module connected to a first input terminal of a drive control module, the first output terminal of the drive control module connected to a first input terminal of an external optical path module; a second output terminal of the drive control module connected to a first input terminal of an internal optical path module, the first output terminal of the internal optical path module connected to a first input terminal of a photoelectric sensing module; a second output terminal of the main control module connected to a first input terminal of a clock module, the first output terminal of the clock module connected to the second input terminals of the external optical path module and the internal optical path module; a second output terminal of the clock module connected to a second input terminal of the photoelectric sensing module; and a first output terminal of the photoelectric sensing module connected to the first input terminal of the main control module. This application can eliminate phase difference fluctuations caused by temperature differences.

Description

Technical Field

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

[0002] As a key device in the field of ranging technology, laser rangefinders achieve high-precision distance measurement of targets through laser signals. Their core principle is based on laser phase ranging, and they can be categorized into four types according to their optical path design: single-transmitter single-receiver, single-transmitter dual-receiver, dual-transmitter single-receiver, and dual-transmitter dual-receiver. Among these, the dual-transmitter single-receiver method is widely used due to its compact structure and controllable cost. It calculates distance by comparing the phases of two laser signals (external and internal optical paths) and is currently the mainstream technology for short-to-medium distance measurement scenarios.

[0003] Existing dual-transmitter, single-receiver laser rangefinders typically use two laser diodes as emission sources: one is the external optical path signal, which is reflected by the object being measured and received by the receiver; the other is the internal optical path signal, which is directly transmitted to the receiver through a preset optical path. At the receiving end, the two signals are mixed with the local oscillator signal, and the distance is calculated by canceling out the phase difference, utilizing the principle that the phase changes of the internal and external optical paths are approximately equal when the characteristics of the laser diodes are identical. To ensure stable transmission power, the system is equipped with a power supply module to regulate the laser diode voltage, and the optical path alignment accuracy is optimized through components such as optical collimators and mounting bases.

[0004] In practical applications, the luminous intensity of laser diodes is easily affected by temperature, and it is difficult to keep the operating temperatures of two laser diodes consistently the same. When temperature differences cause their characteristics to deviate, the phase changes in the inner and outer optical paths cannot be completely canceled out, the phase difference stability decreases, and this directly leads to an increase in the phase error of the signal after mixing.

[0005] This temperature sensitivity ultimately affects the distance calculation process, reducing the accuracy of the measurement results. This is especially true in scenarios with large fluctuations in ambient temperature, where the accumulation of errors is more significant, becoming a bottleneck that restricts the improvement of the accuracy of dual-transmitter single-receiver laser rangefinders. Utility Model Content

[0006] To address the deficiencies mentioned in the background art, this application provides a laser rangefinder circuit and a laser rangefinder, which uses a VCSEL (Vertical-Cavity Surface-Emitting Laser) as the internal optical path emission source. By utilizing its stable emission signal and minimal temperature-dependent luminous intensity, phase difference fluctuations caused by temperature differences are eliminated.

[0007] In a first aspect, this application provides a laser rangefinder circuit, comprising: a main control module, a drive control module, an external optical path module, an internal optical path module, a clock module, and a photoelectric sensing module; wherein the external optical path module is a laser diode; and the internal optical path module is a vertical cavity surface-emitting laser. The first output terminal of the main control module is connected to the first input terminal of the drive control module, and the first output terminal of the drive control module is connected to the first input terminal of the external optical path module, for sending external optical path signals to the photoelectric sensing module through the external optical path; The second output terminal of the drive control module is connected to the first input terminal of the internal optical path module, and the first output terminal of the internal optical path module is connected to the first input terminal of the photoelectric sensing module, for sending internal optical path signals to the photoelectric sensing module through the internal optical path; The second output terminal of the main control module is connected to the first input terminal of the clock module. The first output terminal of the clock module is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, and is used to provide radio frequency clock signals to the external optical path module or the internal optical path module. The second output terminal of the clock module is connected to the second input terminal of the photoelectric sensing module, and is used to provide the photoelectric sensing module with a local oscillator clock signal; The first output terminal of the photoelectric sensing module is connected to the first input terminal of the main control module, and is used to output the mixing signal to the main control module to calculate the distance based on the mixing signal.

[0008] Optionally, it may also include: a display module and a button module; The communication terminal of the display module is connected to the communication terminal of the main control module, and the output terminal of the button module is connected to the second input terminal of the main control module.

[0009] Optional features also include: a temperature sensing module; The output of the temperature sensing module is connected to the third input of the main control module, and is used to feed back temperature information to the main control module.

[0010] Optionally, it may also include: a temperature compensation module; the temperature compensation module is a high-voltage bias power supply; The input terminal of the temperature compensation module is connected to the third output terminal of the main control module, and the output terminal of the temperature compensation module is connected to the third input terminal of the photoelectric sensing module, which is used to provide a temperature compensation signal to reduce the influence of the temperature information.

[0011] Optionally, the drive control module includes a system power supply, a laser emission power supply, and a single-pole double-throw switch; The system power supply is equipped with a signal source. The output terminal of the system power supply is connected to the first input terminal of the laser emitting power supply, and the second input terminal of the laser emitting power supply is connected to the first output terminal of the main control module. The output terminal of the laser emitting power supply is connected to the single-pole terminal of the single-pole double-throw switch, and the double-throw terminal of the single-pole double-throw switch is connected to the first input terminal of the external optical path module and the first input terminal of the internal optical path module, respectively.

[0012] Optionally, the connection between the photoelectric sensing module and the main control module further includes a low-pass amplifier; The input terminal of the low-pass amplifier is connected to the first output terminal of the photoelectric sensing module, and the output terminal of the low-pass amplifier is connected to the first input terminal of the main control module.

[0013] Optionally, the clock module includes a clock control unit, an RF clock driver, and a local oscillator clock driver; The clock control unit integrates a phase-locked loop, a field-programmable gate array, programmable logic devices, and a digital frequency synthesizer; The first input terminal of the clock control unit is connected to the second output terminal of the main control module, the first output terminal of the clock control unit is connected to the input terminal of the RF clock driver, and the output terminal of the RF clock driver is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, respectively. The second output terminal of the clock control unit is connected to the input terminal of the local oscillator clock driver, and the output terminal of the local oscillator clock driver is connected to the second input terminal of the photoelectric sensing module.

[0014] Optionally, the photoelectric sensing module includes an avalanche photodiode and a PN junction photodiode.

[0015] Optionally, the external light route is composed of a first lens and a second lens.

[0016] Secondly, this application provides a laser rangefinder with a circuit structure incorporating the aforementioned laser rangefinder circuit.

[0017] The beneficial effects of this application are as follows: The main control module, as the core of the system, connects to the drive control module through the first output terminal to drive the external optical path module (laser diode, LD) to emit external optical path signals to the object under test, and at the same time drives the internal optical path module (vertical cavity surface emission laser, VCSEL) to directly send internal optical path signals to the photoelectric sensing module through a preset optical channel; on the other hand, it controls the clock module through the second output terminal to generate a radio frequency clock signal (RF_CLK) and a local oscillator clock signal (LO_CLK). RF_CLK is synchronously supplied to the external optical path and internal optical path modules to ensure the frequency consistency of the signals emitted by the LD and VCSEL, while LO_CLK is sent to the photoelectric sensing module for mixing with the received optical signal.

[0018] The photoelectric sensing module receives the reflected signal from the external optical path (diffusely reflected by the object under test) and the reference signal from the internal optical path (directly emitted by the VCSEL). Under the action of the local oscillator clock, it performs frequency mixing, converting the high-frequency optical signal into a processable intermediate-frequency electrical signal, and finally outputs it to the first input terminal of the main control module.

[0019] In summary, compared to existing dual-transmitter single-receiver laser rangefinders that use two laser diodes (LDs) as the inner and outer optical path emission sources, this application uses a VCSEL as the inner optical path emission source. Its emission signal is stable and the light intensity is minimally affected by temperature, making it suitable as a reference signal source. This eliminates the phase difference fluctuations caused by temperature differences in the dual-LD scheme. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the module connection of the laser rangefinder circuit provided in the embodiments of this application; Figure 2 This is a circuit connection diagram of the laser rangefinder circuit provided in the embodiments of this application. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions of this disclosure, and to fully understand and implement the process of how this disclosure applies technical means to solve technical problems and achieve corresponding technical effects, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, not all embodiments. The embodiments of this disclosure and the various features within them can be combined with each other without conflict, and the resulting technical solutions are all within the protection scope of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort should fall within the protection scope of this disclosure.

[0022] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0024] Reference Figure 1 , Figure 1 This is a schematic diagram of the module connections of the laser rangefinder circuit provided in this application embodiment. The diagram illustrates several key modules involved in the laser rangefinder circuit proposed in this application, including: a main control module, a drive control module, an external optical path module, an internal optical path module, a clock module, and a photoelectric sensing module. The external optical path module is a laser diode; the internal optical path module is a vertical-cavity surface-emitting laser. The following is a detailed description... Figure 1 Please provide a detailed explanation: The first output terminal of the main control module is connected to the first input terminal of the drive control module, and the first output terminal of the drive control module is connected to the first input terminal of the external optical path module, for sending external optical path signals to the photoelectric sensing module through the external optical path; The main control module is the core control unit of the laser rangefinder, responsible for coordinating system logic, data processing, and module collaboration. The drive control module is an intermediate unit connecting the main control module and the actuators, used to convert the control signals of the main control module into power signals to drive the external optical path module. The external optical path module is the laser diode (LD) emitting component, which includes a laser diode, an optical collimating lens, etc., used to generate and emit a measurement beam pointing towards the object being measured. The photoelectric sensing module is the core component for receiving optical signals, which includes photoelectric conversion devices such as avalanche photodiodes (APD) and PN junction photodiodes (PIN), used to convert optical signals into electrical signals.

[0025] Specifically, the main control module sends control commands (such as PWM or DAC signals) to the first input of the drive control module through its first output terminal. The drive control module adjusts the output voltage or current according to the commands, and then transmits the output to the first input of the external optical path module through its first output terminal to drive the laser diode (LD) to work. Under the action of the drive signal, the laser diode emits a laser beam, which is calibrated into parallel light by an optical collimating lens and then directed towards the object under test, forming an external optical path signal. After diffuse reflection by the object under test, this signal is focused by a receiving collimating lens onto the photoelectric sensing module, completing the transmission and reception of the external optical path signal.

[0026] More specifically, the external optical path consists of a first lens and a second lens. In the external optical path module, the initial beam emitted by the laser diode (LD) is divergent and is first collimated by the first lens (optical collimating lens). By adjusting the relative distance between the first lens and the LD, the divergent beam is converted into parallel light, ensuring that the laser beam is directed towards the object under test in a stable beam shape, reducing light spot diffusion during transmission. When the laser is diffusely reflected by the object under test, the reflected light returns in a divergent state. At this time, the second lens (receiving collimating lens) adjusts its distance from the photoelectric sensing module to focus the divergent reflected light into a converging beam, which is then precisely projected onto the photosensitive surface of the photoelectric sensor, completing the efficient collection of the light signal.

[0027] Furthermore, the second output terminal of the drive control module is connected to the first input terminal of the internal optical path module, and the first output terminal of the internal optical path module is connected to the first input terminal of the photoelectric sensing module, for sending internal optical path signals to the photoelectric sensing module through the internal optical path.

[0028] Among them, the internal optical path module is the vertical cavity surface-emitting laser (VCSEL), which serves as the source of the internal optical path signal. Its emitted signal is stable and minimally affected by temperature. It is directly transmitted to the photoelectric sensing module through a preset optical path to form a comparison benchmark with the external optical path signal.

[0029] Specifically, the second output of the drive control module receives control commands (such as PWM or DAC adjustment signals) from the main control module, converts them into drive voltage or current adapted to the internal optical path module (VCSEL), and drives the VCSEL to work through the first input of the internal optical path module. Under the action of the drive signal, the VCSEL emits an internal optical path laser with the same frequency as the external optical path signal. This signal does not pass through the external object being measured, but is directly transmitted to the first input of the photoelectric sensing module through a preset optical path inside the device. It is received by the photoelectric sensor (such as APD, PIN) and converted into an electrical signal, which serves as the reference signal for the system in subsequent data processing.

[0030] More specifically, refer to Figure 2 , Figure 2This is a circuit connection diagram of the laser rangefinder circuit provided in the embodiment of this application. The drive control module includes a system power supply, a laser emission power supply, and a single-pole double-throw switch. The system power supply is equipped with a signal source. The output terminal of the system power supply is connected to the first input terminal of the laser emitting power supply, and the second input terminal of the laser emitting power supply is connected to the first output terminal of the main control module. The output terminal of the laser emitting power supply is connected to the single-pole terminal of the single-pole double-throw switch, and the double-throw terminal of the single-pole double-throw switch is connected to the first input terminal of the external optical path module and the first input terminal of the internal optical path module, respectively.

[0031] The drive control module is the core unit in the laser rangefinder that coordinates power distribution and transmission channel switching. It consists of a system power supply, a laser emission power supply, and a single-pole double-throw switch (SW-SPDT). The system power supply provides the basic operating voltage for the entire drive control module, and its built-in "signal source" can output a stable reference voltage or enable signal to ensure stable power supply to downstream modules. The laser emitting power supply is a precision power component controlled by the main control module, and its output voltage can be adjusted by PWM or DAC. The single-pole double-throw switch is a mechanical or electronic switch that realizes the switching of the emission channel. Its single-pole terminal is a common input, and its double-throw terminal is connected to the external optical path module and the internal optical path module respectively. By switching, a single power supply can provide time-sharing power to two emitting devices.

[0032] Specifically, the system power supply provides a base DC voltage to the first input of the laser emitting power supply through its output terminal, while simultaneously outputting an enable signal from a built-in signal source to ensure the laser emitting power supply starts. The second input of the laser emitting power supply receives control commands sent from the first output of the main control module, and converts the base voltage input to the system power supply into an adjustable drive voltage according to the commands. The output of the laser emitting power supply is connected to the single-pole terminal of a single-pole double-throw switch. The main control module controls the switching state of the switch to selectively transmit the drive voltage through the double-throw terminal to either the first input of the external optical path module or the first input of the internal optical path module.

[0033] Furthermore, the second output terminal of the main control module is connected to the first input terminal of the clock module, and the first output terminal of the clock module is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, for providing radio frequency clock signals to the external optical path module or the internal optical path module.

[0034] The clock module is the core unit in the laser rangefinder that generates and distributes high-precision clock signals, providing a stable high-frequency reference signal for the system. The radio frequency clock signal (RF_CLK) is the high-frequency carrier signal output by the clock module, used to drive the external optical path module (laser diode, LD) and the internal optical path module (VCSEL) to perform high-frequency modulation, ensuring the frequency consistency and anti-interference capability of the transmitted signal.

[0035] Specifically, the main control module sends control commands (such as a reference clock signal or configuration parameters) to the first input of the clock module through its second output. Under the coordinated action of the PLL and DDS, the clock module generates an RF clock signal (RF_CLK) synchronized with the main control module. This signal is transmitted through the first output of the clock module to the second inputs of both the external optical path module and the internal optical path module, serving as the modulation reference for the LD and VCSEL. Driven by RF_CLK, the LD in the external optical path module modulates the laser signal to the RF frequency band before transmitting; the VCSEL in the internal optical path module, under the same RF_CLK control, transmits a reference signal at the same frequency as the external optical path signal. By sharing the same RF clock source, strict synchronization of the transmission frequencies is achieved, ensuring the stability of the phase difference during subsequent mixing processing.

[0036] Furthermore, the second output terminal of the clock module is connected to the second input terminal of the photoelectric sensing module, and is used to provide a local oscillator clock signal to the photoelectric sensing module.

[0037] The local oscillator clock signal is a local oscillation signal generated by the clock module. Its frequency is designed in conjunction with the radio frequency clock signal (RF_CLK) to perform frequency mixing with the received optical signal in the optoelectronic sensing module, downconverting the high-frequency optical signal to intermediate frequency or baseband, which facilitates subsequent filtering, amplification and analog-to-digital conversion.

[0038] Specifically, the second output of the clock module transmits the generated local oscillator clock signal to the second input of the photoelectric sensing module, where it is mixed with the external optical path reflection signal (reflected by the object being measured) and the internal optical path reference signal (directly emitted by the VCSEL) received by the photoelectric sensor. The external optical path signal carries the measured distance information, and the internal optical path signal serves as a reference. Under the influence of the local oscillator clock signal, both signals generate a difference frequency with the local oscillator signal, forming an intermediate frequency electrical signal. It is worth noting that the frequency of this intermediate frequency signal is much lower than the frequency of the original optical signal. Based on this, this application proposes: The connection between the photoelectric sensing module and the main control module further includes: a low-pass amplifier; The input terminal of the low-pass amplifier is connected to the first output terminal of the photoelectric sensing module, and the output terminal of the low-pass amplifier is connected to the first input terminal of the main control module.

[0039] Specifically, noise can be effectively filtered out and amplified by a low-pass amplifier, and finally sent to the ADC channel of the main control module for analog-to-digital conversion to provide raw data for distance calculation.

[0040] More specifically, the clock module includes a clock control unit, an RF clock driver, and a local oscillator clock driver; The clock control unit integrates a phase-locked loop, a field-programmable gate array, programmable logic devices, and a digital frequency synthesizer; The first input terminal of the clock control unit is connected to the second output terminal of the main control module, the first output terminal of the clock control unit is connected to the input terminal of the RF clock driver, and the output terminal of the RF clock driver is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, respectively. The second output terminal of the clock control unit is connected to the input terminal of the local oscillator clock driver, and the output terminal of the local oscillator clock driver is connected to the second input terminal of the photoelectric sensing module.

[0041] The clock control unit is the core processing unit of the clock module, integrating a phase-locked loop (PLL), a field-programmable gate array (FPGA), a programmable logic device (CPLD), and a digital frequency synthesizer (DDS). It is responsible for generating, synchronizing, and regulating the high-frequency clock signal required by the system. The RF clock driver is a driving circuit that amplifies and shapes the RF clock signal (RF_CLK) output by the clock control unit, ensuring that the external and internal optical path modules obtain stable high-frequency modulation signals. The local oscillator clock driver is a driving circuit that amplifies and filters the local oscillator clock signal (LO_CLK) output by the clock control unit, providing a high-quality mixing reference signal for the optoelectronic sensing module.

[0042] Specifically, the second output of the main control module sends configuration commands (such as frequency parameters and synchronization signals) to the first input of the clock control unit. The clock control unit locks the reference clock to a stable high-frequency signal through its internally integrated PLL, and then the DDS generates a programmable RF clock and a local oscillator clock. The FPGA / CPLD is responsible for coordinating the timing of the PLL and DDS to ensure phase synchronization of the two clock signals. The first output of the clock control unit transmits the RF clock signal to the RF clock driver. After amplification and shaping, it is sent to the second inputs of the external optical path module and the internal optical path module, respectively, to drive the LD and VCSEL to emit laser signals at the same frequency. The second output transmits the local oscillator clock signal to the local oscillator clock driver. After low-noise amplification, it is sent to the second input of the photoelectric sensing module for mixing with the received optical signal.

[0043] Furthermore, the first output terminal of the photoelectric sensing module is connected to the first input terminal of the main control module, and is used to output the mixing signal to the main control module to calculate the distance based on the mixing signal.

[0044] Among them, the mixed signal is an intermediate frequency electrical signal generated by the photoelectric sensing module after mixing the received external optical path reflected signal (carrying the measured distance information) with the internal optical path reference signal (VCSEL emission) under the action of the local oscillator clock. It contains the phase difference or time difference information of the internal and external optical paths and is the core data source for the main control module to calculate the distance.

[0045] Specifically, after receiving the reflected signal from the external optical path and the reference signal from the internal optical path, the photoelectric sensing module mixes the two optical signals with the local oscillator clock signal (LO_CLK) through an internal mixer, converting the high-frequency optical signal into a low-frequency intermediate-frequency electrical signal (i.e., the mixed signal). This mixed signal is then filtered and amplified by a low-pass amplifier and transmitted to the first input of the main control module through the first output of the photoelectric sensing module.

[0046] Subsequently, the main control module performs analog-to-digital conversion (ADC) on the mixed signal, extracts the phase difference or time difference information, the phase difference of the external optical path signal reflects the distance of the measured object, and the phase difference of the internal optical path signal serves as a reference to offset temperature errors. Finally, the actual distance from the laser rangefinder to the measured object is calculated through an algorithm.

[0047] More specifically, it also includes: a temperature sensing module; The output of the temperature sensing module is connected to the third input of the main control module, and is used to feed back temperature information to the main control module.

[0048] It also includes: a temperature compensation module; the temperature compensation module is a high-voltage bias power supply; The input terminal of the temperature compensation module is connected to the third output terminal of the main control module, and the output terminal of the temperature compensation module is connected to the third input terminal of the photoelectric sensing module, which is used to provide a temperature compensation signal to reduce the influence of the temperature information.

[0049] The temperature sensing module is a detection unit used to collect the temperature of the environment or core components in real time. It usually includes a temperature sensor and is located near the photoelectric sensing module. It can convert physical temperature into an electrical signal and transmit it to the main control module. The temperature compensation module is specifically a high-voltage bias power supply (HV_bais) in this embodiment of the application. It is used to provide a reverse bias high voltage for the photoelectric sensor. Its output voltage can be adjusted by the main control module to offset the effect of temperature changes on the performance of the photoelectric sensor.

[0050] Specifically, the temperature sensing module collects temperature data from the photoelectric sensing module in real time and transmits it to the third input of the main control module through its output. The main control module analyzes the received temperature information, and if it detects a temperature deviation from the reference range, it sends a control command to the temperature compensation module through its third output. The temperature compensation module adjusts its output voltage according to the command, and transmits the adjusted reverse bias high voltage through its output to the third input of the photoelectric sensing module, thereby changing the intensity of the avalanche multiplication effect of the photoelectric sensor and thus offsetting the sensitivity fluctuations caused by temperature changes.

[0051] In addition, it also includes: a display module and a button module; The communication terminal of the display module is connected to the communication terminal of the main control module, and the output terminal of the button module is connected to the second input terminal of the main control module.

[0052] The display module is the human-machine interface output unit of the laser rangefinder, used to visually present the system's operating status, measurement data, and operation menus. It is usually implemented using an LCD display. The button module is the human-machine interface input unit, which includes physical buttons or touch buttons, used to receive user operation commands (such as starting measurement and setting parameters) and transmit them to the main control module.

[0053] Specifically, the communication terminal of the display module (such as SPI or I2C interface) is connected to the communication terminal of the main control module. The main control module transmits the calculated ranging results and system status (such as laser power and temperature) to the display module through the communication protocol. The display module converts the digital signals into visual information and refreshes the interface in real time. The output terminal of the button module is connected to the second input terminal of the main control module. When the user presses a button, the button module generates a level signal (such as high-low level transition). The main control module detects this signal through the second input terminal, parses it into a specific instruction (such as "switch unit" or "save data"), and triggers the corresponding system response (such as re-measurement or parameter adjustment).

[0054] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A laser rangefinder circuit, characterized by include: The system comprises a main control module, a drive control module, an external optical path module, an internal optical path module, a clock module, and a photoelectric sensing module; the external optical path module is a laser diode; and the internal optical path module is a vertical-cavity surface-emitting laser. The first output terminal of the main control module is connected to the first input terminal of the drive control module, and the first output terminal of the drive control module is connected to the first input terminal of the external optical path module, for sending external optical path signals to the photoelectric sensing module through the external optical path; The second output terminal of the drive control module is connected to the first input terminal of the internal optical path module, and the first output terminal of the internal optical path module is connected to the first input terminal of the photoelectric sensing module, for sending internal optical path signals to the photoelectric sensing module through the internal optical path; The second output terminal of the main control module is connected to the first input terminal of the clock module. The first output terminal of the clock module is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, and is used to provide radio frequency clock signals to the external optical path module or the internal optical path module. The second output terminal of the clock module is connected to the second input terminal of the photoelectric sensing module, and is used to provide the photoelectric sensing module with a local oscillator clock signal; The first output terminal of the photoelectric sensing module is connected to the first input terminal of the main control module, and is used to output the mixing signal to the main control module to calculate the distance based on the mixing signal.

2. The laser rangefinder circuit according to claim 1, characterized in that, Also includes: Display module and button module; The communication terminal of the display module is connected to the communication terminal of the main control module, and the output terminal of the button module is connected to the second input terminal of the main control module.

3. The laser rangefinder circuit according to claim 1, characterized in that, Also includes: Temperature sensing module; The output of the temperature sensing module is connected to the third input of the main control module, and is used to feed back temperature information to the main control module.

4. The laser rangefinder circuit according to claim 3, characterized in that, Also includes: Temperature compensation module; the temperature compensation module is a high-voltage bias power supply; The input terminal of the temperature compensation module is connected to the third output terminal of the main control module, and the output terminal of the temperature compensation module is connected to the third input terminal of the photoelectric sensing module, which is used to provide a temperature compensation signal to reduce the influence of the temperature information.

5. The laser rangefinder circuit according to claim 1, characterized in that, The drive control module includes a system power supply, a laser emission power supply, and a single-pole double-throw switch; The system power supply is equipped with a signal source. The output terminal of the system power supply is connected to the first input terminal of the laser emitting power supply, and the second input terminal of the laser emitting power supply is connected to the first output terminal of the main control module. The output terminal of the laser emitting power supply is connected to the single-pole terminal of the single-pole double-throw switch, and the double-throw terminal of the single-pole double-throw switch is connected to the first input terminal of the external optical path module and the first input terminal of the internal optical path module, respectively.

6. The laser rangefinder circuit of claim 1, wherein, The connection between the photoelectric sensing module and the main control module further includes: a low-pass amplifier; The input terminal of the low-pass amplifier is connected to the first output terminal of the photoelectric sensing module, and the output terminal of the low-pass amplifier is connected to the first input terminal of the main control module.

7. The laser rangefinder circuit of claim 1, wherein, The clock module includes a clock control unit, an RF clock driver, and a local oscillator clock driver; The clock control unit integrates a phase-locked loop, a field-programmable gate array, programmable logic devices, and a digital frequency synthesizer; The first input terminal of the clock control unit is connected to the second output terminal of the main control module, the first output terminal of the clock control unit is connected to the input terminal of the RF clock driver, and the output terminal of the RF clock driver is connected to the second input terminal of the external optical path module and the second input terminal of the internal optical path module, respectively. The second output terminal of the clock control unit is connected to the input terminal of the local oscillator clock driver, and the output terminal of the local oscillator clock driver is connected to the second input terminal of the photoelectric sensing module.

8. The laser rangefinder circuit of claim 1, wherein, The photoelectric sensing module includes an avalanche photodiode and a PN junction photodiode.

9. The laser rangefinder circuit according to claim 1, characterized in that, The external optical path is composed of a first lens and a second lens.

10. A laser rangefinder, characterized in that, A circuit structure incorporating the laser rangefinder circuit as described in any one of claims 1-9.

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