Laser ranging device

Abstract

This invention discloses a laser ranging device, relating to the field of laser ranging technology. The laser ranging device includes an external power supply connection terminal, a boost circuit, a control circuit, a voltage multiplier circuit, a photoelectric converter, and a laser emitting circuit. An external voltage is connected through the external power supply connection terminal. The boost circuit raises the external voltage to a first voltage. The control circuit controls the boost circuit to periodically turn on and off. The voltage multiplier circuit further raises the first voltage and outputs it to the photoelectric converter and the laser emitting circuit. The photoelectric converter receives the laser signal reflected from the target and converts it into an electrical signal. The control circuit controls the laser emitting circuit to emit laser pulses and receives the converted electrical signal from the photoelectric converter. The distance to the target is calculated based on the time difference between the emitted laser pulse and the electrical signal. The technical solution provided by this invention can solve the problems of limited boost amplitude, complex circuitry, and high cost in existing technologies.

Description

Technical Field

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

[0002] Due to its unique characteristics such as strong directionality, high brightness, good monochromaticity, and good coherence, laser has been widely used as a light source for photoelectric ranging, leading to the rapid development of laser ranging technology and its widespread application in military, scientific research, and construction fields. To fully leverage the advantages of laser ranging technology, researchers have continuously conducted multifaceted research, particularly using single-photon laser receivers to replace traditional APDs, which significantly improves the sensitivity of laser reception, thereby enhancing the ranging range, accuracy, and speed. However, the emergence of single-photon laser receivers has brought new technical challenges: these devices require high driving voltages, typically tens or even hundreds of volts. In existing technologies, traditional voltage multiplier circuits primarily operate under AC power conditions. In DC power supply scenarios, the DC needs to be converted to AC before undergoing voltage multiplication and rectification, resulting in complex circuits, high costs, and large sizes. While traditional Boost converters can operate under DC power, their voltage boost is limited, making it difficult to achieve output voltages of hundreds of volts. Summary of the Invention

[0003] The main objective of this invention is to propose a laser ranging device that aims to solve the problems of limited boost amplitude, complex circuitry, and high cost in existing technologies.

[0004] To achieve the above objectives, the laser ranging device proposed in this invention includes: External power supply connection terminal, used to connect to external voltage; A boost circuit, wherein the input terminal of the boost circuit is connected to the external power supply connection terminal, the boost circuit being used to boost the external voltage to a first voltage and output the first voltage; A control circuit is connected to the controlled terminal of the boost circuit, and the control circuit is used to control the boost circuit to periodically turn on and off. A voltage multiplier circuit is connected to the output terminal of the boost circuit. The voltage multiplier circuit is used to boost the first voltage and output it. A photoelectric converter, wherein the first input terminal of the photoelectric converter is connected to the output terminal of the voltage multiplier circuit, and the output terminal of the photoelectric converter is connected to the control circuit, the photoelectric converter is used to receive the laser signal reflected from the target being measured and convert the laser signal into an electrical signal; A laser emitting circuit, wherein the first input terminal of the laser emitting circuit is connected to the output terminal of the voltage multiplier circuit, the controlled terminal of the laser emitting circuit is connected to the control circuit, and the output terminal of the laser emitting circuit is used to emit laser pulses; The control circuit is further configured to control the laser emitting circuit to emit laser pulses and receive the electrical signal converted by the photoelectric converter, and calculate the distance to the target based on the time difference between the emitted laser pulse and the electrical signal.

[0005] In one embodiment, the boost circuit includes a first inductor and a first switching transistor; The first end of the first inductor is connected to the external power supply connection terminal, and the second end of the first inductor is connected to the input terminal of the voltage multiplier circuit and the first end of the first switching transistor, respectively. The second terminal of the first switching transistor is connected to ground, and the controlled terminal of the first switching transistor is connected to the control circuit.

[0006] In one embodiment, when the control circuit controls the first switching transistor to be turned on, the first inductor stores electrical energy; When the control circuit controls the first switching transistor to turn off, the first inductor releases the electrical energy to the voltage multiplier circuit.

[0007] In one embodiment, the voltage multiplier circuit includes at least one voltage multiplier stage.

[0008] In one embodiment, the first-stage voltage multiplier circuit includes a first diode, a second diode, a first capacitor, and a second capacitor; The anode of the first diode is connected to the output terminal of the boost circuit and the first terminal of the second capacitor, respectively. The cathode of the first diode is connected to the first terminal of the first capacitor and the anode of the second diode, respectively. The second terminal of the first capacitor is connected to ground, and the cathode of the second diode is connected to the second terminal of the second capacitor.

[0009] In one embodiment, the voltage multiplier circuit further includes a first-stage voltage multiplier circuit and a second-stage voltage multiplier circuit; The input terminal of the first-stage voltage multiplier circuit is connected to the output terminal of the boost circuit, and the output terminal of the first-stage voltage multiplier circuit is connected to the input terminal of the second-stage voltage multiplier circuit. The first-stage voltage multiplier circuit is used to boost the first voltage to a first multiple voltage. The second-stage voltage multiplier circuit is used to boost the first multiple voltage to a second multiple voltage; Wherein, the second multiple voltage is greater than the first multiple voltage.

[0010] In one embodiment, when the voltage multiplier circuit includes three or more voltage multiplier circuits, the output voltage of the Nth voltage multiplier circuit is N times the first voltage; Where N is the number of stages in the voltage multiplier circuit.

[0011] In one embodiment, the laser ranging device further includes a voltage feedback circuit; The input terminal of the voltage feedback circuit is connected to the output terminal of the voltage multiplier circuit, and the output terminal of the voltage feedback circuit is connected to the feedback input terminal of the control circuit. The voltage feedback circuit is used to acquire the output voltage and send the feedback signal to the control circuit, and the control circuit adjusts the control signal based on the feedback signal.

[0012] In one embodiment, the photoelectric converter is a single-photon photoelectric converter, and the operating voltage range of the single-photon photoelectric converter is 50 volts to 200 volts.

[0013] In one embodiment, the laser emitting circuit includes a laser diode and a driving switch transistor; The anode of the laser diode is connected to the output terminal of the voltage multiplier circuit, the cathode of the laser diode is connected to the first terminal of the driving switch, the second terminal of the driving switch is connected to ground, and the controlled terminal of the driving switch is connected to the control circuit.

[0014] The technical solution of this invention includes an external power supply connection terminal, a boost circuit, a control circuit, a voltage multiplier circuit, a photoelectric converter, and a laser emitting circuit. The external power supply connection terminal is used to connect to an external voltage. The input terminal of the boost circuit is connected to the external power supply connection terminal, and the boost circuit is used to boost the external voltage to a first voltage and output the first voltage. The control circuit is connected to the controlled terminal of the boost circuit, and the control circuit is used to control the boost circuit to periodically turn on and off. The voltage multiplier circuit is connected to the output terminal of the boost circuit, and the voltage multiplier circuit is used to boost the first voltage and output it. The first input terminal of the photoelectric converter is connected to the output terminal of the voltage multiplier circuit, and the output terminal of the photoelectric converter is connected to the control circuit. The photoelectric converter is used to receive the laser signal reflected from the target and convert the laser signal into an electrical signal. The first input terminal of the laser emitting circuit is connected to the output terminal of the voltage multiplier circuit, and the controlled terminal of the laser emitting circuit is connected to the control circuit. The output terminal of the laser emitting circuit is used to emit laser pulses. The control circuit is also used to control the laser emitting circuit to emit laser pulses and receive the electrical signal converted by the photoelectric converter, and calculate the distance of the target based on the time difference between the emitted laser pulse and the electrical signal.

[0015] Thus, the laser ranging device connects to an external voltage via an external power supply terminal. A boost circuit raises this external voltage to a first voltage level. A control circuit periodically turns the boost circuit on and off. A voltage multiplier circuit further boosts this first voltage before outputting it to the photoelectric converter and the laser emitting circuit. The photoelectric converter receives the laser signal reflected from the target and converts it into an electrical signal. The control circuit then controls the laser emitting circuit to emit laser pulses and receives the converted electrical signal from the photoelectric converter. The distance to the target is calculated based on the time difference between the emitted laser pulse and the electrical signal. Therefore, through the cascaded structure of the boost and voltage multiplier circuits, the circuit structure is simple, providing a suitable high driving voltage for the laser emitting circuit and the photoelectric converter, and completing the ranging functions of laser emission, echo reception, and distance calculation under the same control circuit. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. 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 This is a schematic diagram of a structure of an embodiment of the laser ranging device provided by the present invention; Figure 2 A circuit diagram of another embodiment of the laser ranging device provided by the present invention; Figure 3 A circuit diagram of yet another embodiment of the laser ranging device provided by the present invention; Figure 4 A circuit diagram of another embodiment of the laser ranging device provided by the present invention.

[0018] Explanation of icon numbers: 100. Laser ranging equipment 10. External power supply connection terminal; 20. Boost circuit; 30. Control circuit; 40. Voltage multiplier circuit; 41. First-stage voltage multiplier circuit; 42. Second-stage voltage multiplier circuit; 50. Photoelectric converter; 60. Laser emitting circuit; 70. Voltage feedback circuit; L1, first inductor; Q1, first switching transistor; D1, first diode; D2, second diode; C1, first capacitor; C2, second capacitor.

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

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

[0021] Due to its unique characteristics such as strong directionality, high brightness, good monochromaticity, and good coherence, laser has been widely used as a light source for photoelectric ranging, leading to the rapid development of laser ranging technology and its widespread application in military, scientific research, and construction fields. To fully leverage the advantages of laser ranging technology, researchers have continuously conducted multifaceted research, particularly using single-photon laser receivers to replace traditional APDs, which significantly improves the sensitivity of laser reception, thereby enhancing the ranging range, accuracy, and speed. However, the emergence of single-photon laser receivers has brought new technical challenges: these devices require high driving voltages, typically tens or even hundreds of volts. In existing technologies, traditional voltage multiplier circuits primarily operate under AC power conditions. In DC power supply scenarios, the DC needs to be converted to AC before undergoing voltage multiplication and rectification, resulting in complex circuits, high costs, and large sizes. While traditional Boost converters can operate under DC power, their voltage boost is limited, making it difficult to achieve output voltages of hundreds of volts.

[0022] Therefore, this invention proposes a laser ranging device, aiming to solve the problems of limited boost amplitude, complex circuitry, and high cost in existing technologies.

[0023] Please see Figure 1 In one embodiment of the present invention, the laser ranging device 100 includes: External power supply connection terminal 10 is used to connect to an external voltage; The boost circuit 20 has its input terminal connected to the external power supply connection terminal 10. The boost circuit 20 is used to boost the external voltage to a first voltage and output the first voltage. Control circuit 30 is connected to the controlled terminal of boost circuit 20. Control circuit 30 is used to control boost circuit 20 to periodically turn on and off. Voltage multiplier circuit 40 is connected to the output terminal of boost circuit 20. Voltage multiplier circuit 40 is used to boost the first voltage and output it. The photoelectric converter 50 has its first input terminal connected to the output terminal of the voltage multiplier circuit 40, and its output terminal connected to the control circuit 30. The photoelectric converter 50 is used to receive the laser signal reflected back from the target and convert the laser signal into an electrical signal. The laser emitting circuit 60 has its first input terminal connected to the output terminal of the voltage multiplier circuit 40, its controlled terminal connected to the control circuit 30, and its output terminal used to emit laser pulses. The control circuit 30 is also used to control the laser emitting circuit 60 to emit laser pulses and receive the electrical signal converted by the photoelectric converter 50, and calculate the distance of the target being measured based on the time difference between the emitted laser pulse and the electrical signal.

[0024] Optionally, the external power supply connection terminal 10 is used to connect an external DC voltage. The external DC voltage is a low-voltage DC power supply, such as 3.6V, 5V, or 12V, provided by a battery or a DC regulated power supply, which can be selected according to the actual situation and is not limited here. The positive terminal of the external power supply connection terminal 10 is connected to the input terminal of the boost circuit 20, and the negative terminal is grounded. It is worth noting that the present invention chooses to use DC power supply instead of AC power supply because the laser rangefinder 100 is usually used in portable applications such as handheld rangefinders and UAV-borne rangefinder modules. These devices are powered by batteries or DC power supplies and do not have readily available AC power supply conditions. The traditional voltage multiplier circuit 40 needs to work under AC input. If the traditional voltage multiplier circuit 40 is used under DC power supply conditions, an additional DC-AC inverter circuit is required to convert DC to AC before voltage multiplication and rectification. This will cause problems such as circuit complexity, high cost, large energy loss, strong electromagnetic interference, and increased size and weight. Without adding an inverter circuit, this invention uses the PWM signal output by the control circuit 30 to control the periodic on and off of the switching transistor, causing the inductor to periodically store and release energy, generating pulse-shaped energy. The voltage multiplier circuit 40 uses the pulses to achieve voltage superposition directly in the DC system through the alternating charging and discharging of the diode and capacitor. This invention has advantages such as simplified circuit, reduced cost, high energy conversion efficiency, low electromagnetic interference, and compatibility with portable devices.

[0025] Optionally, the control circuit 30 can be implemented using a main controller, such as an MCU (Micro Controller Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), or a SOC (System On Chip).

[0026] Optionally, the input terminal of the boost circuit 20 is connected to the external power supply connection terminal 10. The boost circuit 20 is a DC-DC Boost circuit 20, used to boost the external DC voltage to a first voltage and output the first voltage through its output terminal. The boost circuit 20 operates under the control of the control circuit 30. When the control circuit 30 controls the internal switching device of the boost circuit 20 to conduct, the internal energy storage element of the boost circuit 20 begins to store energy; when the control circuit 30 controls the switching device to open, the energy storage element releases the stored energy, which is superimposed with the external voltage and output, thereby making the output voltage higher than the external voltage. By adjusting the duty cycle of the control signal output by the control circuit 30, the amplitude of the first voltage can be adjusted: the larger the duty cycle, the higher the first voltage; the smaller the duty cycle, the lower the first voltage.

[0027] Optionally, the input terminal of the voltage multiplier circuit 40 is connected to the output terminal of the boost circuit 20. The voltage multiplier circuit 40 is used to further boost the first voltage and output a second voltage. It should be noted that the conventional voltage multiplier circuit 40 needs to operate under AC input, while the voltage multiplier circuit 40 of this invention operates under DC input conditions, and, in conjunction with the periodic switching signal output by the control circuit 30, achieves voltage superposition. The voltage multiplier circuit 40 utilizes the periodic on and off of the switching transistor, and through the alternating charging and discharging of the diode and capacitor, boosts the first voltage to two, three, or even higher factors.

[0028] Optionally, the first input terminal of the photoelectric converter 50 is connected to the output terminal of the voltage multiplier circuit 40, and the output terminal of the photoelectric converter 50 is connected to the control circuit 30. The photoelectric converter 50 is used to receive the laser signal reflected from the target and convert the laser signal into an electrical signal. The photoelectric converter 50 is a single-photon photoelectric converter, such as a single-photon avalanche diode or a silicon photomultiplier tube. Such devices require a high driving voltage of tens or even hundreds of volts to operate normally; in this embodiment, the high driving voltage is provided by the voltage multiplier circuit 40.

[0029] Optionally, the connection between the photoelectric converter 50 and the control circuit 30 can take several forms. One is that the output of the photoelectric converter 50 is directly connected to the analog input of the control circuit 30, where sampling and quantization are performed by the internal analog-to-digital converter of the control circuit 30. Another is that the output of the photoelectric converter 50 undergoes signal processing (such as amplification, comparison, or shaping) before being connected to the control circuit 30, to improve signal quality and anti-interference capability. Regardless of the method used, the control circuit 30 can receive the electrical signal characterizing the arrival time of the echo laser.

[0030] The photoelectric converter 50 can also be configured with different device types and packages to suit specific application requirements. For example, in miniaturized devices requiring high integration, an on-chip integrated single-photon avalanche diode array can be used; in long-range ranging devices requiring high sensitivity, a silicon photomultiplier tube with a large photosensitive surface can be used; and in cost-sensitive applications, a discretely packaged single-photon avalanche diode can be used. Regardless of the specific device used, its driving voltage is provided by the voltage multiplier circuit 40, and its output electrical signal is received and processed by the control circuit 30.

[0031] Optionally, the first input terminal of the laser emitting circuit 60 is connected to the output terminal of the voltage multiplier circuit 40, the controlled terminal of the laser emitting circuit 60 is connected to the control circuit 30, and the output terminal of the laser emitting circuit 60 is used to emit laser pulses. The laser emitting circuit 60 is controlled by the control circuit 30. When the control circuit 30 issues a emission command, the laser emitting circuit 60 uses the second voltage provided by the voltage multiplier circuit 40 as a drive to generate and emit laser pulses. The laser emitting circuit 60 can be designed in various forms, such as using a laser diode as a light source and controlling the lighting and extinguishing of the laser diode through a corresponding driving method. The laser emitting circuit 60 can also adjust the width, power, and emission timing of the laser pulse as needed to adapt to different ranging distances and measurement accuracy requirements. The appropriate configuration can be selected based on the actual working environment and is not limited here. The laser pulse output by the laser emitting circuit 60 is directed towards the target being measured, and after reflection by the target, an echo signal is formed, which is received by the photoelectric converter 50.

[0032] Thus, the laser ranging device 100 is connected to an external voltage via the external power supply connection terminal 10. The boost circuit 20 boosts the external voltage to a first voltage. The control circuit 30 controls the boost circuit 20 to periodically turn on and off. The voltage multiplier circuit 40 further boosts the first voltage and outputs it to the photoelectric converter 50 and the laser emitting circuit 60. The photoelectric converter 50 receives the laser signal reflected back from the target and converts it into an electrical signal. The control circuit 30 controls the laser emitting circuit 60 to emit laser pulses and receives the electrical signal converted by the photoelectric converter 50. The distance to the target is calculated based on the time difference between the emitted laser pulse and the electrical signal. Therefore, through the cascaded structure of the boost circuit 20 and the voltage multiplier circuit 40, the circuit structure is simple, providing a suitable high driving voltage for the laser emitting circuit 60 and the photoelectric converter 50, and completing the ranging functions of laser emission, echo reception, and distance calculation under the same control circuit 30.

[0033] like Figure 2 and Figure 3 As shown, in one embodiment, the boost circuit 20 includes a first inductor L1 and a first switching transistor Q1; The first end of the first inductor L1 is connected to the external power supply connection terminal 10, and the second end of the first inductor L1 is connected to the input terminal of the voltage multiplier circuit 40 and the first end of the first switching transistor Q1, respectively. The second terminal of the first switching transistor Q1 is connected to ground, and the controlled terminal of the first switching transistor Q1 is connected to the control circuit 30.

[0034] Optionally, the boost circuit 20 includes a first inductor L1 and a first switching transistor Q1. The first end of the first inductor L1 is connected to the external power supply connection terminal 10, meaning the first end of the first inductor L1 is connected to the positive terminal of the external DC voltage. The second end of the first inductor L1 is connected to both the input terminal of the voltage multiplier circuit 40 and the first end of the first switching transistor Q1. This can be understood as the second end of the first inductor L1 serving as a common connection point, simultaneously connected to the input terminal of the voltage multiplier circuit 40 and the first end of the first switching transistor Q1. The second end of the first switching transistor Q1 is connected to ground. The boost circuit 20 is controlled by the control circuit 30, specifically divided into an energy storage stage and an energy release stage. When the control circuit 30 controls the first switch Q1 to be turned on, the first switch Q1 is in the closed state. The external voltage is applied to the two ends of the first inductor L1 through the external power supply connection terminal 10. The positive terminal of the external voltage goes through the first inductor L1 and the first switch Q1 to the ground terminal. Current flows through the first inductor L1, and the current increases linearly with time. The first inductor L1 converts electrical energy into magnetic energy and stores it. When the control circuit 30 controls the first switch Q1 to be turned off, the first switch Q1 is in the open state. The magnetic energy stored in the first inductor L1 is converted into electrical energy and released. Since the inductor current cannot change abruptly, a back electromotive force is generated across the first inductor L1. The back electromotive force is in the same direction as the external voltage. The two are superimposed, causing the voltage at the second end of the first inductor L1 to rise and be higher than the external voltage. The increased voltage is output through the second end of the first inductor L1 to the input terminal of the voltage multiplier circuit 40, providing energy input for the voltage multiplier circuit 40. The control signal output by the control circuit 30 is a periodic signal. The first switch Q1 is repeatedly turned on and off, and the first inductor L1 repeatedly stores and releases energy, thereby forming a pulse voltage higher than the external voltage at the input of the voltage multiplier circuit 40.

[0035] like Figure 2 and Figure 3 As shown, in one embodiment, the voltage multiplier circuit 40 includes at least one voltage multiplier circuit.

[0036] Optionally, the voltage multiplier circuit 40 includes at least one stage. This can be understood as the voltage multiplier circuit 40 having one, two, or more stages, the specific number of stages determined by the driving voltage required by the photoelectric converter 50 and the laser emitting circuit 60. Each stage of the voltage multiplier circuit 40 is cascaded sequentially, with the output of the previous stage serving as the input of the next stage, progressively increasing the voltage.

[0037] Optionally, when the voltage multiplier circuit 40 includes a first-stage voltage multiplier circuit, the first-stage voltage multiplier circuit includes a first diode D1, a second diode D2, a first capacitor C1, and a second capacitor C2. The anode of the first diode D1 is connected to the output terminal of the boost circuit 20 and the first terminal of the second capacitor C2, respectively. The cathode of the first diode D1 is connected to the first terminal of the first capacitor C1 and the anode of the second diode D2, respectively. The second terminal of the first capacitor C1 is connected to ground, and the cathode of the second diode D2 is connected to the second terminal of the second capacitor C2. The second terminal of the second capacitor C2 serves as the output terminal of the first-stage voltage multiplier circuit, outputting the boosted voltage. Specifically, when the control circuit 30 controls the first switching transistor Q1 in the boost circuit 20 to turn off, the inductor releases energy. This energy, after being superimposed with the external DC voltage, charges the first capacitor C1 through the first diode D1, and the voltage across the first capacitor C1 is charged to an amplitude close to the first voltage. When the control circuit 30 turns on the first switch Q1 in the boost circuit 20, the electrical energy on the first capacitor C1 charges the second capacitor C2 through the second diode D2. The voltage across the second capacitor C2 is charged to a level close to that of the first capacitor C1, i.e., close to the amplitude of the first voltage. When the switch turns off again, the inductor releases energy again. This energy is superimposed on the voltage stored in the second capacitor C2 and output through the output terminal of the voltage multiplier circuit 40. At this time, the voltage at the output terminal is approximately twice the first voltage. Through the periodic turning on and off of the first switch Q1, the charging and discharging process is repeated, and the first-stage voltage multiplier circuit achieves a double voltage output under DC power supply.

[0038] Optionally, when the voltage multiplier circuit 40 includes a first-stage voltage multiplier circuit 41 and a second-stage voltage multiplier circuit 42, the input terminal of the first-stage voltage multiplier circuit 41 is connected to the output terminal of the boost circuit 20, and the output terminal of the first-stage voltage multiplier circuit 41 is connected to the input terminal of the second-stage voltage multiplier circuit 42. The first-stage voltage multiplier circuit 41 is used to boost the first voltage to a first multiple voltage, and the second-stage voltage multiplier circuit 42 is used to boost the first multiple voltage to a second multiple voltage, wherein the second multiple voltage is greater than the first multiple voltage. The first-stage voltage multiplier circuit 41 adopts the structure of the first-stage voltage multiplier circuit described above, boosting the first voltage output by the boost circuit 20 to twice the voltage (i.e., the first multiple voltage), and outputting it to the input terminal of the second-stage voltage multiplier circuit 42. The second-stage voltage multiplier circuit 42 is also composed of diodes and capacitors, and its structure is the same as that of the first-stage voltage multiplier circuit 41. The input terminal of the second-stage voltage multiplier circuit 42 is connected to the output terminal of the first-stage voltage multiplier circuit 41 (i.e., twice the voltage), and through the same working principle, the twice voltage is further superimposed to output a higher voltage. Specifically, in the first switching cycle, the boost circuit 20 and the first-stage voltage multiplier circuit 41 work together. The first-stage voltage multiplier circuit 41 outputs twice the voltage, which is stored in the input capacitor of the second-stage voltage multiplier circuit 42. In subsequent switching cycles, when the first switch Q1 is turned off, the energy released by the inductor is superimposed on the doubled voltage output by the first-stage voltage multiplier circuit 41 and enters the second-stage voltage multiplier circuit 42. When the first switch Q1 is turned on, the capacitor inside the second-stage voltage multiplier circuit 42 performs charge transfer, further boosting the superimposed voltage. Finally, the output of the second-stage voltage multiplier circuit 42 can obtain four times the first voltage.

[0039] Optionally, when the voltage multiplier circuit 40 includes three or more stages, the output voltage of the Nth stage voltage multiplier circuit 40 is N times the first voltage, where N is the number of stages in the voltage multiplier circuit 40. Specifically, each stage of the voltage multiplier circuit adopts the same diode-capacitor topology and is cascaded sequentially. The first stage voltage multiplier circuit 41 boosts the first voltage to twice its original value, the second stage voltage multiplier circuit 42 boosts the voltage from twice its original value to four times its original value, the third stage voltage multiplier circuit boosts the voltage from four times its original value to six times its original value, and so on. With each additional stage, the output voltage increases by the magnitude of the first voltage. In one example, the voltage multiplier circuit 40 includes three stages: the first stage, the second stage, and the third stage. The input terminal of the first stage voltage multiplier circuit 41 is connected to the output terminal of the boost circuit 20, outputting twice the voltage; the input terminal of the second stage voltage multiplier circuit 42 is connected to the output terminal of the first stage voltage multiplier circuit 41, outputting four times the voltage; and the input terminal of the third stage voltage multiplier circuit is connected to the output terminal of the second stage voltage multiplier circuit 42, outputting six times the voltage. Therefore, the output voltage of the third-stage voltage multiplier circuit is three times that of the first voltage (i.e., when N=3, the output voltage is three times that of the first voltage).

[0040] Optionally, for any positive integer N, the voltage multiplier circuit 40 includes N stages. The input terminal of the first-stage voltage multiplier circuit 41 is connected to the output terminal of the boost circuit 20, the input terminal of the second-stage voltage multiplier circuit 42 is connected to the output terminal of the first-stage voltage multiplier circuit 41, and so on, with the input terminal of the Nth-stage voltage multiplier circuit 40 connected to the output terminal of the (N-1)th-stage voltage multiplier circuit. Through the periodic switching of the first switching transistor Q1, charge is transferred step by step, and voltage is superimposed step by step. Finally, the output voltage of the Nth-stage voltage multiplier circuit is N times the first voltage. It should be noted that the above multiplication factor relationship holds true under ideal conditions. In actual circuits, due to the forward voltage drop of the diodes and the charging and discharging losses of the capacitors, the actual output voltage is slightly lower than the theoretical value, but the basic multiplication factor relationship remains unchanged. Those skilled in the art can reduce this deviation by selecting diodes with low forward voltage drops and capacitors with low equivalent series resistance. The number of stages N of the voltage multiplier circuit 40 is determined according to the driving voltage required by the photoelectric converter 50 and the laser emitting circuit 60. Let the first output voltage of the boost circuit 20 be V1, and the required driving voltage be Vout. Then the required number of stages N satisfies: N≈Vout / V1. More stages result in a higher output voltage, but the voltage ratings of the diodes and capacitors, as well as the settling time of the output voltage, must also be considered. Those skilled in the art can choose an appropriate number of stages based on specific application requirements; no limitation is made here.

[0041] like Figure 2 and Figure 3 As shown, in one embodiment, the laser ranging device 100 further includes a voltage feedback circuit 70; The input terminal of the voltage feedback circuit 70 is connected to the output terminal of the voltage multiplier circuit 40, and the output terminal of the voltage feedback circuit 70 is connected to the feedback input terminal of the control circuit 30. The voltage feedback circuit 70 is used to collect the output voltage and send the feedback signal to the control circuit 30. The control circuit 30 adjusts the control signal based on the feedback signal.

[0042] In this embodiment, the input terminal of the voltage feedback circuit 70 is connected to the output terminal of the voltage multiplier circuit 40, and is used to acquire the voltage output by the voltage multiplier circuit 40; the output terminal of the voltage feedback circuit 70 is connected to the feedback input terminal of the control circuit 30, and is used to send the acquired feedback signal to the control circuit 30. The voltage feedback circuit 70 is used to acquire the output voltage and send the feedback signal to the control circuit 30, and the control circuit 30 adjusts its output control signal based on the received feedback signal.

[0043] Optionally, the voltage feedback circuit 70 can be implemented using a resistor divider network, consisting of two resistors connected in series. The connection point of the two resistors serves as the output terminal of the feedback signal, and the other ends of the two resistors are connected to the output terminal of the voltage multiplier circuit 40 and ground, respectively. By selecting an appropriate resistor ratio, the high voltage output by the voltage multiplier circuit 40 is proportionally divided and reduced to a voltage range acceptable to the control circuit 30. The voltage feedback circuit 70 can also employ a voltage follower or proportional amplifier circuit composed of operational amplifiers to achieve impedance matching or signal conditioning, or a dedicated voltage detection chip to improve detection accuracy and temperature stability.

[0044] Optionally, when the voltage multiplier circuit 40 outputs a second voltage, the voltage feedback circuit 70 samples this second voltage and sends the sampled feedback signal to the feedback input terminal of the control circuit 30. The control circuit 30 internally compares the received feedback signal with a preset reference voltage and determines whether the current output voltage reaches the desired value based on the comparison result. If the feedback signal is lower than the reference voltage, it indicates that the output voltage is too low, and the control circuit 30 adjusts its output control signal accordingly, for example, by increasing the duty cycle of the PWM signal to increase the output voltage of the boost circuit 20 and the voltage multiplier circuit 40; if the feedback signal is higher than the reference voltage, it indicates that the output voltage is too high, and the control circuit 30 decreases the duty cycle of the PWM signal to decrease the output voltage. Through the above closed-loop adjustment, the control circuit 30 can stabilize the output voltage of the voltage multiplier circuit 40 near the preset target value. By setting the voltage feedback circuit 70, the laser ranging device 100 can monitor the output voltage of the voltage multiplier circuit 40 in real time and adjust the parameters of the control signal according to voltage changes, thereby maintaining a stable output voltage even under external voltage fluctuations or load changes. This is particularly important for the single-photon photoelectric converter 50 and the laser emitting circuit 60, as these devices have high requirements for the stability of the driving voltage. Voltage fluctuations can lead to decreased detection sensitivity, reduced ranging accuracy, or even device damage. Furthermore, the addition of the voltage feedback circuit 70 allows the output voltage to be flexibly adjusted according to different ranging requirements. For example, the driving voltage can be increased to enhance detection sensitivity when measuring distant targets, while the driving voltage can be decreased to save power when measuring nearby targets.

[0045] In one embodiment, the photoelectric converter 50 is a single-photon photoelectric converter, and the operating voltage range of the single-photon photoelectric converter is 50 volts to 200 volts.

[0046] Optionally, the single-photon photoelectric converter 50 refers to a device capable of detecting weak light signals at the single-photon level, such as a single-photon avalanche diode or a silicon photomultiplier tube. These devices require a relatively high reverse bias voltage to enter Geiger mode or linear avalanche amplification mode, thereby achieving single-photon level detection sensitivity. If the operating voltage is too low, the device cannot enter the avalanche multiplication region, resulting in insufficient detection sensitivity and difficulty in effectively receiving echo signals from distant or weakly reflective targets. If the operating voltage is too high, it may exceed the device's breakdown voltage, leading to device damage or a sharp increase in the dark count rate, affecting ranging accuracy and device lifespan.

[0047] Optionally, the operating voltage range of a single-photon photoelectric converter is 50 volts to 200 volts. This range covers the typical operating conditions of most commercial single-photon photoelectric converters. For example, some silicon photomultiplier tubes operate at 50 volts to 80 volts, some single-photon avalanche diodes operate at 80 volts to 150 volts, and some high-voltage single-photon detectors can operate at 150 volts to 200 volts. Different single-photon photoelectric converter devices have different optimal operating voltage points depending on their materials, structure, and manufacturing process, but all fall within the 50 volt to 200 volt range.

[0048] In one embodiment, the laser emitting circuit 60 includes a laser diode and a driving switch transistor; The anode of the laser diode is connected to the output terminal of the voltage multiplier circuit 40, the cathode of the laser diode is connected to the first terminal of the driving switch, the second terminal of the driving switch is connected to the ground terminal, and the controlled terminal of the driving switch is connected to the control circuit 30.

[0049] Optionally, the laser emitting circuit 60 includes a laser diode and a driving switch. The anode of the laser diode is connected to the output terminal of the voltage multiplier circuit 40, receiving the second voltage output by the voltage multiplier circuit 40 as its driving energy; the cathode of the laser diode is connected to the first terminal of the driving switch. The second terminal of the driving switch is connected to ground, and the controlled terminal of the driving switch is connected to the control circuit 30. The control circuit 30 controls the conduction and disconnection of the driving switch by outputting a control signal to the controlled terminal of the driving switch.

[0050] Optionally, when the control circuit 30 needs to emit laser pulses, it outputs a conduction signal to the controlled terminal of the drive switch, turning on the drive switch. At this time, the cathode of the laser diode is grounded through the drive switch, and the laser diode receives a forward bias voltage provided by the voltage multiplier circuit 40. Current flows through the laser diode, and it emits laser pulses. When the control circuit 30 needs to stop emitting, it outputs a disconnect signal to the controlled terminal of the drive switch, turning off the drive switch. The cathode of the laser diode is disconnected from ground, and no forward current flows through the laser diode, causing it to stop emitting light. By controlling the conduction time of the drive switch, the width of the laser pulse can be controlled; by controlling the conduction sequence of the drive switch, the emission time and number of laser pulses can be controlled.

[0051] Optionally, the laser diode can be a pulsed laser diode. These devices are suitable for operation under short-pulse, high-current conditions and can output high-peak-power laser pulses, which is beneficial for long-distance ranging. The driving switch can be a metal-oxide-semiconductor field-effect transistor, with its drain as the first terminal, source as the second terminal, and gate as the controlled terminal; or it can be a bipolar transistor, with its collector as the first terminal, emitter as the second terminal, and base as the controlled terminal.

[0052] Based on the above embodiments, the first switching transistor Q1 of the present invention can be implemented using a dedicated boost converter chip, such as... Figure 4 As shown. The boost chip integrates a switching transistor and its driving circuit, and is equipped with a switching pin and a feedback pin. The switching pin of the boost chip serves as the output terminal of the boost circuit 20 and is connected to the input terminal of the voltage multiplier circuit 40, used to output pulsed energy; the feedback pin of the boost chip serves as the feedback input terminal of the control circuit 30, used to receive the feedback signal of the output voltage. Specifically, the working principle of the boost chip is similar to that of the first switching transistor Q1, but it has higher integration and more precise control capabilities. The feedback pin of the boost chip has a sensitive swing rate, which can quickly sense small changes in the output voltage. The output voltage of the voltage multiplier circuit 40 is sampled by voltage feedback circuit 70 and then sent to the feedback pin of the boost chip. The boost chip internally compares the voltage received at the feedback pin with the internal reference voltage, and adjusts the pulse width or frequency of the PWM signal output by the switching pin according to the comparison result. When the output voltage is too low, the boost chip increases the duty cycle or adjustment frequency of the PWM signal, causing the boost circuit 20 and voltage multiplier circuit 40 to output a higher voltage; when the output voltage is too high, the boost chip decreases the duty cycle or adjustment frequency of the PWM signal, causing the output voltage to decrease. Through the closed-loop regulation mechanism, the boost chip can stabilize the output voltage, keeping it always near the preset target value.

[0053] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A laser ranging device, characterized in that, The laser ranging device includes: External power supply connection terminal, used to connect to external voltage; A boost circuit, wherein the input terminal of the boost circuit is connected to the external power supply connection terminal, the boost circuit being used to boost the external voltage to a first voltage and output the first voltage; A control circuit is connected to the controlled terminal of the boost circuit, and the control circuit is used to control the boost circuit to periodically turn on and off. A voltage multiplier circuit is connected to the output terminal of the boost circuit. The voltage multiplier circuit is used to boost the first voltage and output it. A photoelectric converter, wherein the first input terminal of the photoelectric converter is connected to the output terminal of the voltage multiplier circuit, and the output terminal of the photoelectric converter is connected to the control circuit, the photoelectric converter is used to receive the laser signal reflected from the target being measured and convert the laser signal into an electrical signal; A laser emitting circuit, wherein the first input terminal of the laser emitting circuit is connected to the output terminal of the voltage multiplier circuit, the controlled terminal of the laser emitting circuit is connected to the control circuit, and the output terminal of the laser emitting circuit is used to emit laser pulses; The control circuit is further configured to control the laser emitting circuit to emit laser pulses and receive the electrical signal converted by the photoelectric converter, and calculate the distance to the target based on the time difference between the emitted laser pulse and the electrical signal.

2. The laser ranging device as described in claim 1, characterized in that, The boost circuit includes a first inductor and a first switching transistor; The first end of the first inductor is connected to the external power supply connection terminal, and the second end of the first inductor is connected to the input terminal of the voltage multiplier circuit and the first end of the first switching transistor, respectively. The second terminal of the first switching transistor is connected to ground, and the controlled terminal of the first switching transistor is connected to the control circuit.

3. The laser ranging device as described in claim 2, characterized in that, When the control circuit controls the first switching transistor to be turned on, the first inductor stores electrical energy. When the control circuit controls the first switching transistor to turn off, the first inductor releases the electrical energy to the voltage multiplier circuit.

4. The laser ranging device as described in claim 1, characterized in that, The voltage multiplier circuit includes at least one voltage multiplier circuit.

5. The laser ranging device as described in claim 4, characterized in that, The first-stage voltage multiplier circuit includes a first diode, a second diode, a first capacitor, and a second capacitor; The anode of the first diode is connected to the output terminal of the boost circuit and the first terminal of the second capacitor, respectively. The cathode of the first diode is connected to the first terminal of the first capacitor and the anode of the second diode, respectively. The second terminal of the first capacitor is connected to ground, and the cathode of the second diode is connected to the second terminal of the second capacitor.

6. The laser ranging device as described in claim 5, characterized in that, The voltage multiplier circuit also includes a first-stage voltage multiplier circuit and a second-stage voltage multiplier circuit; The input terminal of the first-stage voltage multiplier circuit is connected to the output terminal of the boost circuit, and the output terminal of the first-stage voltage multiplier circuit is connected to the input terminal of the second-stage voltage multiplier circuit. The first-stage voltage multiplier circuit is used to boost the first voltage to a first multiple voltage. The second-stage voltage multiplier circuit is used to boost the first multiple voltage to a second multiple voltage; Wherein, the second multiple voltage is greater than the first multiple voltage.

7. The laser ranging device as described in claim 6, characterized in that, When the voltage multiplier circuit includes three or more voltage multiplier circuits, the output voltage of the Nth voltage multiplier circuit is N times the first voltage; Where N is the number of stages in the voltage multiplier circuit.

8. The laser ranging device as described in claim 1, characterized in that, The laser ranging device also includes a voltage feedback circuit; The input terminal of the voltage feedback circuit is connected to the output terminal of the voltage multiplier circuit, and the output terminal of the voltage feedback circuit is connected to the feedback input terminal of the control circuit. The voltage feedback circuit is used to acquire the output voltage and send the feedback signal to the control circuit, and the control circuit adjusts the control signal based on the feedback signal.

9. The laser ranging device as described in claim 1, characterized in that, The photoelectric converter is a single-photon photoelectric converter, and the operating voltage range of the single-photon photoelectric converter is 50 volts to 200 volts.

10. The laser ranging device as described in claim 1, characterized in that, The laser emitting circuit includes a laser diode and a driving switch transistor; The anode of the laser diode is connected to the output terminal of the voltage multiplier circuit, the cathode of the laser diode is connected to the first terminal of the driving switch, the second terminal of the driving switch is connected to ground, and the controlled terminal of the driving switch is connected to the control circuit.

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