Laser ranging system capable of resisting surface interference

Abstract

The invention discloses a laser ranging system resistant to surface interference. The laser ranging system comprises a substrate, and a first laser emission module and a ranging module which are located on one side of the substrate. The distance measuring module comprises a signal receiving module, and a preset distance exists between the first laser transmitting module and the signal receiving module; the first laser transmitting module is used for transmitting a first laser pulse; the signal receiving module is used for receiving an optical pulse signal reflected after the first laser pulse is projected to a target object; and the signal receiving module is used for acquiring a first time from the first laser pulse emission moment to the time when the signal receiving module receives the optical pulse signal, and determining the distance of the target object according to the first time. By means of the structure, the signal crosstalk problem is solved, and the distance measurement accuracy of the target object is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser ranging, in particular to a laser ranging system capable of resisting surface interference. BACKGROUND

[0002] The laser ranging system is a technology that uses laser beams to measure distance. Its basic function is to emit laser pulses or continuous waves and measure the time required for these light signals to return from the transmitter to the target object and then to the receiver, thereby calculating the distance of the target object. This technology has been widely used in many fields due to its high precision, fast response, and non-contact characteristics.

[0003] The existing laser ranging system needs a very small volume in the process of ranging due to the miniaturization of the chip, such as being used in mobile phones, so that the laser emitting surface and the signal receiving surface are very close. Figure 1 T is the laser emitting end, and R is the signal receiving end. When there are stains, fingerprints, oil stains, water droplets, or other objects that can cause refraction and reflection on the surface of the chip, the reference Figure 2 and Figure 3 , Figure 2 indicates that when there is a certain thickness of semi / full transparent glass / plastic or other semi-transparent material cover on the surface of the chip, light will be reflected in the cover, causing signal crosstalk between the laser reflected from the target object and the reflected light. Figure 3 indicates that when there are stains, fingerprints, oil stains, or water droplets on the cover, these attachments will increase the signal crosstalk caused by the transparent cover due to the short distance between the laser emitting surface and the receiving surface of the signal receiving module. Especially under the mechanism of Time Correlated Single Photon Counting (TCSPC), the statistical histogram will have a near distance peak, reference Figure 4 , the nearest peak of the signal emitting unit is caused by signal crosstalk, and the second peak is the intensity of the target object reflection. In actual application, the first peak is easily mistaken for the intensity of the target object reflection, and the distance is determined according to the intensity, affecting the accuracy and maximum ranging ability of the ranging. SUMMARY

[0004] The present application provides a laser ranging system capable of resisting surface interference, by setting a first laser emitting module and a predetermined distance between the first laser emitting module and the signal receiving module, to solve the problem of signal crosstalk and improve the ranging accuracy of the target object.

[0005] The application provides an anti-surface interference laser ranging system, which comprises a substrate, a first laser emission module and a ranging module located on one side of the substrate; the ranging module comprises a signal receiving module; and a preset distance exists between the first laser emission module and the signal receiving module.

[0006] The first laser emission module is used for emitting a first laser pulse.

[0007] The signal receiving module is used for receiving a light pulse signal reflected after the first laser pulse is projected to a target object.

[0008] The signal receiving module is used for obtaining a first time used from a first laser pulse emission moment to a light pulse signal receiving moment of the signal receiving module, and determining a distance of the target object according to the first time.

[0009] Optionally, the preset distance is greater than or equal to 3 mm.

[0010] Optionally, the system further comprises a temperature sensor; the temperature sensor is electrically connected with the signal receiving module.

[0011] The temperature sensor is used for detecting a current environmental temperature; the signal receiving module is used for obtaining the current environmental temperature when the light pulse signal has temperature drift, and performing temperature compensation on the first time based on a preset corresponding relationship, so as to determine the distance of the target object according to the first time after the temperature compensation; wherein the preset corresponding relationship is a preset corresponding relationship between the environmental temperature and the first time.

[0012] Optionally, the ranging module further comprises a second laser emission module; and the signal receiving module comprises a reference signal receiving unit.

[0013] The second laser emission module is used for emitting a second laser pulse; the reference signal receiving unit is used for receiving the second laser pulse to form a reference laser pulse; and the signal receiving module is used for obtaining a second time from a second laser pulse emission moment to a reference laser pulse acquisition moment when the light pulse signal has temperature drift, and determining the distance of the target object according to a difference between the first time and the second time.

[0014] Optionally, the system further comprises a shielding module; the signal receiving module further comprises an actual signal receiving unit; and a preset interval exists between the actual signal receiving unit and the reference signal receiving unit.

[0015] The shielding module is located at part of a light emitting position of the second laser emission module, so that the reference signal receiving unit receives the second laser pulse, and the actual signal receiving unit cannot receive a light pulse signal reflected after the second laser pulse is projected to the target object.

[0016] Optionally, the system further comprises a shell; and the shell comprises a first part and a second part which are isolated from each other.

[0017] The second part is provided with a second light inlet hole, the reference signal receiving unit and the second laser emission module are located in the first part, and the actual signal receiving unit is located in the second part.

[0018] Optionally, the first part is provided with a first light outlet hole.

[0019] The shielding module covers the first light outlet hole.

[0020] Optionally, the system further comprises a lens.

[0021] The lens is embedded into the second light inlet hole.

[0022] Optionally, the system further comprises a first series resistance and a second series resistance; the signal receiving module comprises a power supply and driving signal generating unit.

[0023] The first series resistance is connected in series between the first laser emission module and the power supply and driving signal generating unit, and the second series resistance is connected in series between the second laser emission module and the power supply and driving signal generating unit.

[0024] The resistance value of the first series resistance is smaller than the resistance value of the second series resistance.

[0025] Optionally, the first laser emission module comprises a vertical cavity surface emitting laser.

[0026] The technical scheme of the present application, by the first laser emission module emitting the first laser pulse, the signal receiving module receiving the light pulse signal reflected after the first laser pulse is projected to the target object, the signal receiving module acquiring the first time used from the first laser pulse emission moment to the light pulse signal received by the signal receiving module, and determining the distance of the target object according to the first time, realizes the accurate measurement of the distance of the target object. In addition, the present embodiment sets that there is a preset distance between the first laser emission module and the signal receiving module, so that when there are stains, fingerprints, oil stains or water beads and other attachments on the surface of the system, the reflected light reflected from the stains, fingerprints, oil stains or water beads and other attachments will not enter the signal receiving module, and will not cause signal crosstalk with the light pulse signal, and will not affect the measurement of the distance of the target object by the signal receiving module. Thus, the problem of signal crosstalk is solved, and the accuracy of the distance measurement of the target object is improved.

[0027] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A schematic diagram of the structure of a distance measuring system provided for the prior art;

[0030] Figure 2 An optical path diagram for a distance measuring system with a cover plate provided in the prior art;

[0031] Figure 3 An optical path diagram for a distance measuring system provided in the prior art when it has attachments such as stains, fingerprints, oil, or water droplets and a cover plate;

[0032] Figure 4 A statistical histogram for a time-correlated single-photon counting mechanism provided for existing technologies;

[0033] Figure 5 This is a schematic diagram of a laser ranging system resistant to surface interference provided in an embodiment of the present invention;

[0034] Figure 6 for Figure 5 The optical path diagram of a laser ranging system that is resistant to surface interference when a cover plate and contaminants such as dirt, fingerprints, oil or water droplets are added;

[0035] Figure 7 This invention provides a statistical histogram of curves after curve manipulation under a time-correlated single-photon counting mechanism.

[0036] Figure 8 This is a schematic diagram of the structure of a second type of laser ranging system for resisting surface interference provided in an embodiment of the present invention;

[0037] Figure 9 This is a schematic diagram of the structure of a third type of laser ranging system for resisting surface interference provided in an embodiment of the present invention;

[0038] Figure 10 This is a schematic diagram of a connection method for a laser ranging system that resists surface interference, provided in an embodiment of the present invention. Detailed Implementation

[0039] In order to make the person skilled in the art better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the present application.

[0040] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0041] In an embodiment, Figure 5 A structural schematic diagram of a surface interference resistant laser ranging system provided by an embodiment of the present application, Figure 6 A structural schematic diagram of a surface interference resistant laser ranging system provided by an embodiment of the present application, Figure 5 A light path diagram when a cover plate and attachments such as stains, fingerprints, oil stains or water droplets are added in a corresponding surface interference resistant laser ranging system, Figure 7 A statistical histogram after curve fitting under a time correlation single photon counting mechanism provided by an embodiment of the present application, the embodiment can be applied to solve the signal crosstalk problem when attachments such as stains, fingerprints, oil stains or water droplets exist on the surface of the system, as shown in the figure, Figures 5 to 7 The system includes a substrate 1, a first laser emitting module 2, a ranging module 3 and a signal receiving module 31 located on one side of the substrate 1; the ranging module 3 includes the signal receiving module 31, and there is a preset distance between the first laser emitting module 2 and the signal receiving module 31; the signal receiving module 31 is electrically connected with the signal receiving module 31; the first laser emitting module 2 is used for emitting a first laser pulse; the signal receiving module 31 is used for receiving a light pulse signal reflected after the first laser pulse is projected to a target object 5; the signal receiving module 31 is used for acquiring a first time used from a first laser pulse emission time to a light pulse signal received by the signal receiving module 31, and determining a distance of the target object 5 according to the first time.

[0042] The substrate 1 supports the ranging system. The first laser emitting module 2 emits a first laser pulse. In this embodiment, the first laser emitting module 2 includes a vertical cavity surface emitting laser (VCSEL). The ranging module 3 is a laser ranging structure, which may include a laser emitting unit and a signal receiving module 31, or only a signal receiving module, depending on the actual situation. In this embodiment, the ranging module 3 includes a signal receiving module 31, which receives the light pulse signal reflected from the target object 5. In addition, the signal receiving module 31 can also serve as the control structure of the system, used to acquire the first time from the moment the first laser pulse is emitted to the moment the signal receiving module 31 receives the light pulse signal, and determine the distance to the target object 5 based on the first time.

[0043] Specifically, when measuring the distance to target object 5, the first laser pulse emitted by the first laser emitting module 2 is projected onto target object 5. The light pulse signal generated after reflection by target object 5 is then incident on signal receiving module 31. During this process, the timing unit in signal receiving module 31 starts timing from the moment the first laser pulse is emitted by the first laser emitting module 2 until the signal receiving module 31 receives the light pulse signal. Signal receiving module 31 acquires this first time and determines the distance to target object 5 based on it. Specifically, signal receiving module 31 can determine the distance between target object 5 and the ranging system by using a preset calculation formula based on the first time and the speed of light.

[0044] It should be noted that in this embodiment, there is a preset distance between the first laser emitting module 2 and the signal receiving module 31. This preset distance can be set to be greater than or equal to 3mm, which is commonly found between chips or modules. For example, the preset distance can be 3mm, 10mm, 15mm, or 20mm, etc., and can be determined according to the actual situation. No limitation is imposed here. In this case, if the cover plate on the surface of the ranging system is too thick or if there are stains, fingerprints, oil, or water droplets that cause signal crosstalk, refer to... Figure 6 Since stains, fingerprints, oil, or water droplets are usually not large or continuous, they only cover part of the first laser emitting module 2 or part of the signal receiving module 31. Furthermore, an isolation structure is provided between the first laser emitting module 2 and the signal receiving module 31. Therefore, after the first laser pulse emitted by the first laser emitting module 2 is incident on the stains, fingerprints, oil, or water droplets on the system surface or the cover plate and reflected, the reflected light will not enter the signal receiving module 31 (see reference). Figure 6The light path of the middle cover plate or the water droplets and the like is not reflected on the water droplets and the like on the signal receiving module 31, so that the signal receiving module 31 cannot receive the light pulse signal, and the distance of the target object 5 cannot be calculated, that is, the signal crosstalk cannot be generated, and thus the signal crosstalk problem is solved. Figure 7 It can be seen that the peak height of the near distance is small, because the laser cannot be conducted through the stains, water droplets and the like, but can be conducted through the upper and lower surfaces of the cover plate, and the peak height of the far distance is the intensity after the target object is reflected, so that the distance can be accurately determined according to the intensity after the target object is reflected, and the ranging accuracy and the maximum ranging capability are improved.

[0045] In addition, the embodiment can also be provided with a control module, and the control module is usually an MCU, which is used for controlling the working logic of the whole system, receiving the signal of the sensor as a whole, and providing a control signal for a lower circuit (usually an actuator or a higher level system main control), so as to realize the start and stop of the ranging system.

[0046] The technical scheme of the embodiment of the application comprises the following steps: the first laser emitting module emits a first laser pulse; the signal receiving module receives a light pulse signal reflected after the first laser pulse is projected to a target object; a first time used from the first laser pulse emission time to the light pulse signal received by the signal receiving module is acquired; and the distance of the target object is determined according to the first time, so that the distance of the target object is accurately measured. In addition, the embodiment is provided with a preset distance between the first laser emitting module and the signal receiving module, so that when there are stains, fingerprints, oil stains or water droplets and the like on the surface of the system, the reflected light reflected from the stains, fingerprints, oil stains or water droplets and the like cannot enter the signal receiving module, so that the signal crosstalk between the reflected light and the light pulse signal cannot be generated, and the measurement of the distance of the target object by the signal receiving module is not affected, so that the signal crosstalk problem is solved, and the accuracy of the target object ranging is improved.

[0047] In another specific embodiment, optionally, Figure 8 A structure schematic diagram of a second anti-surface interference laser ranging system provided by the embodiment of the application is shown in the figure, and the system further comprises a temperature sensor 6. Figure 8 The temperature sensor 6 is electrically connected with the signal receiving module 31; the temperature sensor 6 is used for detecting the current environmental temperature; the signal receiving module 31 is used for acquiring the current environmental temperature when the light pulse signal has temperature drift, and performing temperature compensation on the first time based on a preset corresponding relationship, so as to determine the distance of the target object 5 according to the first time after the temperature compensation; and the preset corresponding relationship is a preset corresponding relationship between the environmental temperature and the first time.

[0048] Specifically, when temperature drift exists in the system, the first laser pulse emitted by the first laser emitting module 2 will be affected by the temperature drift, thus affecting the transmission time of the optical pulse signal and causing a deviation in the distance to the final target object 5. To solve the temperature drift problem, the signal receiving module 31 will acquire the current ambient temperature detected by the temperature sensor 6 and, based on the current ambient temperature and the stored preset correspondence, which is a preset correspondence between ambient temperature and first time, that is, the preset correspondence is the first time corresponding to the ambient temperature without temperature drift. After acquiring the first time, the ambient temperature corresponding to the absence of temperature drift can be determined. Combined with the current ambient temperature, the first time can be compensated to obtain the compensated first time. Using the temperature-compensated first time, the distance to the target object 5 is determined. The distance to the target object 5 obtained at this time is the actual distance, thus solving the influence of temperature drift on the distance to the target object 5 and improving the ranging accuracy.

[0049] In another specific embodiment, optionally, Figure 9 This is a schematic diagram of the third type of surface interference-resistant laser ranging system provided in an embodiment of the present invention, with reference to... Figure 9 As shown, the ranging module 3 also includes a second laser emitting module 32; the signal receiving module 31 includes a reference signal receiving unit 311; the second laser emitting module 32 is used to emit a second laser pulse, and the reference signal receiving unit 311 is used to receive the second laser pulse to form a reference laser pulse; the signal receiving module 31 is used to obtain the second time from the time of emission of the second laser pulse to the time of obtaining the reference laser pulse when there is temperature drift in the optical pulse signal, and determine the distance of the target object 5 based on the difference between the first time and the second time.

[0050] The second laser emitting module 32 is identical to the first laser emitting module 31, and is used to emit a second laser pulse. The reference signal receiving unit 311 is used to receive the second laser pulse, which is a reference laser pulse, meaning that the second laser pulse is an optical signal directly from the second laser emitting module 32 and is not affected by any environmental factors.

[0051] Specifically, when the system has temperature drift, the optical pulse signal will have a certain time delay due to the temperature drift, resulting in inaccurate final ranging. Therefore, in order to eliminate the temperature drift, the ranging module 3 in the embodiment includes a second laser emitting module 32, and the signal receiving module 31 includes a reference signal receiving unit 311. At this time, the second laser emitting module 32 will emit a second laser pulse, and the second laser pulse will be directly reflected to the reference signal receiving unit 311, so that the reference signal receiving unit 311 receives the second laser pulse, i.e. the reference laser pulse, which is affected by the same temperature drift and can be used for signal subtraction to eliminate the temperature drift. Therefore, the signal receiving module 31 will obtain a second time from the time when the second laser pulse is emitted to the time when the reference laser pulse is obtained, and the difference between the first time with temperature drift and the second time with temperature drift is obtained. The difference value is the time not affected by the temperature drift, i.e. the time after temperature compensation. The distance of the target object 5 is determined by using the time after temperature compensation for calculation. At this time, the distance of the target object 5 obtained is the actual distance, which solves the influence of temperature drift on the distance of the target object 5 and improves the ranging accuracy.

[0052] In another specific embodiment, optionally, continuing to refer to Figure 9 As shown, the system further includes a shielding module 7; the signal receiving module 31 further includes an actual signal receiving unit 312; there is a preset interval between the actual signal receiving unit 312 and the reference signal receiving unit 311; the shielding module 7 is located at part of the light emitting position of the second laser emitting module 32, so that the reference signal receiving unit 311 receives the second laser pulse, and the actual signal receiving unit 312 cannot receive the optical pulse signal reflected by the target object 5 after the second laser pulse is projected to the target object 5.

[0053] Among them, the shielding module 7 is used to shield part of the light emitting position of the second laser emitting module 32, so that the second laser pulse emitted by the second laser emitting module 32 can only be sent to the reference signal receiving unit 311 and cannot be sent to the target object 5, so that the actual signal receiving unit 312 cannot receive the optical pulse signal reflected by the target object 5, preventing signal crosstalk, and at the same time solving the temperature drift problem. In addition, the shielding module 7 is provided in the embodiment to prevent signal crosstalk, so as to solve the problems of temperature drift and signal crosstalk on the basis of not changing the existing structure, and the structure is simple.

[0054] Optionally, continuing to refer to Figure 9 , the system further includes a housing 8; the housing 8 includes a first part 81 and a second part 82 which are isolated from each other; the second part 82 is provided with a second light inlet hole 821; the reference signal receiving unit 311 and the second laser emitting module 32 are located in the first part 81, and the actual signal receiving unit 312 is located in the second part 82.

[0055] Specifically, the shell 8 is used to protect the system. The shell 8 comprises a first part 81 and a second part 82 which are isolated from each other. The first part 81 is used to arrange the reference signal receiving unit 311 and the second laser emitting module 32, and the second part 82 is used to arrange the actual signal receiving unit 312. Thus, the second laser pulse emitted by the second laser emitting module 32 can be transmitted to the reference signal receiving unit 311 after being reflected by the inner wall of the first part 81 of the shell 8. The first laser pulse can be projected onto the target object 5 through the second light inlet hole 821, and then reflected to the actual signal receiving unit 312 through the second light inlet hole 821. In addition, the first laser emitting module 2 can be arranged on one side surface of the base 1 alone, or can be arranged together with the actual signal receiving unit 312 in the shell 8. When the first laser emitting module 2 is arranged in the shell 8, it can be arranged in the second part 82. The shell 8 can also be provided with a third part. The third part is provided with a third light outlet hole. The second part 82 is located between the first part 81 and the third part. At this time, the first laser pulse is projected onto the target object 5 through the third light outlet hole, and then reflected to the actual signal receiving unit 312 through the second light inlet hole 821.

[0056] Optionally, with reference to Figure 9 , the first part 81 is provided with a first light outlet hole 811; and the shielding module 7 covers the first light outlet hole 811.

[0057] Specifically, the first part 81 is provided with the first light outlet hole 811, and the shielding module 7 covers the first light outlet hole 811. When the second laser pulse reaches the first light outlet hole 811, it will be blocked by the shielding module 7 and will not be transmitted outside the shell 8, but will be reflected to the reference signal receiving unit 311 from the first light outlet hole 811 to form a reference laser pulse. Because the distance between the light emitting surface of the first laser emitting module 2 and the receiving surface of the signal receiving module 3 is very close, such as only 3mm, when there are attachments such as dirt, fingerprints, oil stains or water droplets on the surface of the system, signal crosstalk will occur in the actual signal receiving unit 312. Therefore, in the embodiment, the shielding module 7 is arranged on the side surface of the first light outlet hole 811 away from the base 1, so that the second laser pulse cannot be projected onto the target object 5 through the first light outlet hole 811, and the reference signal receiving unit 311 can only normally receive the reference laser pulse. In this way, the shielding module 7 is arranged without changing the existing structure, and the problems of temperature drift and signal crosstalk are solved.

[0058] Optionally, with reference to Figure 9 , the system further comprises a lens 9; and the lens 9 is embedded into the second light inlet hole 821.

[0059] Lens 9 can be a converging lens, used to focus the first laser pulse onto the target object 5. By embedding lens 9 into the second light-entry aperture 821, the actual signal receiving unit 312 can receive the light pulse signal reflected from the target object 5 through lens 9.

[0060] Optional, Figure 10 This is a schematic diagram of the connection method of a laser ranging system with anti-surface interference provided in an embodiment of the present invention, with reference to... Figure 9 and Figure 10 As shown, the system also includes a first series resistor 10 and a second series resistor 20; the signal receiving module 3 includes a power supply and drive signal generating unit 33; the first series resistor 10 is connected in series between the first laser emitting module 2 and the power supply and drive signal generating unit 33, and the second series resistor 20 is connected in series between the second laser emitting module 32 and the power supply and drive signal generating unit 33; the resistance value of the first series resistor 10 is less than the resistance value of the second series resistor 20.

[0061] Specifically, the power supply and drive signal generation unit 33 is used to transmit pulse drive electrical signals to the first laser emitting module 2 and the second laser emitting module 32, ensuring that the first laser emitting module 2 emits a first laser pulse, while the second laser emitting module 32 emits a second laser pulse. Since the first laser pulse emitted by the first laser emitting module 2 is used for ranging the target object 5, the second laser pulse emitted by the second laser emitting module 32 is mainly used to form a reference laser pulse. Therefore, the intensity of the first laser pulse is preferably greater than that of the second laser pulse to ensure that energy is not wasted and that the first laser pulse is accurately projected onto the target object 5. In this embodiment, a first series resistor 10 and a second series resistor 20 are provided. The first series resistor 10 is connected in series between the first laser emitting module 2 and the power supply and drive signal generating unit 33, and the second series resistor 20 is connected in series between the second laser emitting module 32 and the power supply and drive signal generating unit 33. In order to save energy, the pulse current flowing to the first laser emitting module 2 can be much greater than the pulse current of the second laser emitting module 32. Even if the resistance value of the first series resistor 10 is less than the resistance value of the second series resistor 20, the ranging accuracy is achieved while maximizing energy utilization.

[0062] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0063] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. A laser ranging system resistant to surface interference, characterized in that, The system includes a substrate, and a first laser emitting module and a ranging module located on one side of the substrate; the ranging module includes a signal receiving module, and a preset distance exists between the first laser emitting module and the signal receiving module; The first laser emitting module is used to emit a first laser pulse; The signal receiving module is used to receive the light pulse signal reflected after the first laser pulse is projected onto the target object; The signal receiving module is also used to acquire the first time from the time the first laser pulse is emitted to the time when the signal receiving module receives the light pulse signal, and to determine the distance of the target object based on the first time.

2. The surface interference-resistant laser ranging system according to claim 1, characterized in that, The preset distance is greater than or equal to 3mm.

3. The surface-interference-resistant laser ranging system according to claim 1, characterized in that, It also includes a temperature sensor; the temperature sensor is electrically connected to the signal receiving module; The temperature sensor is used to detect the current ambient temperature; the signal receiving module is also used to acquire the current ambient temperature when there is temperature drift in the light pulse signal, and to perform temperature compensation on the first time based on a preset correspondence, so as to determine the distance of the target object according to the temperature-compensated first time; wherein, the preset correspondence is a preset correspondence between the ambient temperature and the first time.

4. The surface-interference-resistant laser ranging system according to claim 1, characterized in that, The ranging module further includes a second laser emitting module; the signal receiving module includes a reference signal receiving unit. The second laser emitting module is used to emit a second laser pulse, and the reference signal receiving unit is used to receive the second laser pulse to form a reference laser pulse; the signal receiving module is used to obtain the second time from the emission time of the second laser pulse to the time when the optical pulse signal has temperature drift, and to determine the distance of the target object based on the difference between the first time and the second time.

5. The surface interference-resistant laser ranging system according to claim 4, characterized in that, It also includes a blocking module; the signal receiving module further includes an actual signal receiving unit; there is a preset interval between the actual signal receiving unit and the reference signal receiving unit; The blocking module is located at a portion of the light-emitting position of the second laser emitting module, so that the reference signal receiving unit receives the second laser pulse, and the actual signal receiving unit does not receive the light pulse signal reflected after the second laser pulse is projected onto the target object.

6. The surface-interference-resistant laser ranging system according to claim 5, characterized in that, It also includes a housing; the housing comprises a first part and a second part that are isolated from each other; the second part is provided with a second light-entry hole; The reference signal receiving unit and the second laser emitting module are located in the first part, and the actual signal receiving unit is located in the second part.

7. The surface-interference-resistant laser ranging system according to claim 6, characterized in that, The first part is provided with a first light-emitting hole; The shielding module covers the first light-emitting hole.

8. The surface-interference-resistant laser ranging system according to claim 6, characterized in that, It also includes lenses; The lens is embedded in the second light-entry hole.

9. The surface-interference-resistant laser ranging system according to claim 4, characterized in that, It also includes a first series resistor and a second series resistor; the signal receiving module includes a power supply and a drive signal generating unit; The first series resistor is connected in series between the first laser emitting module and the power supply and drive signal generating unit, and the second series resistor is connected in series between the second laser emitting module and the power supply and drive signal generating unit; The resistance of the first series resistor is less than the resistance of the second series resistor.

10. The surface-interference-resistant laser ranging system according to claim 1, characterized in that, The first laser emitting module includes a vertical cavity surface-emitting laser.

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