Laser radar double-receiving device and laser radar

Abstract

The utility model relates to a laser radar double-receiving device and a laser radar. The device can comprise a spectroscope, a total reflection mirror, a first receiving device and a second receiving device, the spectroscope is arranged in front of the first receiving device, a preset angle is formed between the spectroscope and the laser beam, the spectroscope is used for dividing the laser beam into two paths, one path is transmitted to the first receiving device, and the other path is reflected to the total reflective mirror; the total reflective mirror is arranged in front of the second receiving device, a preset angle is formed between the total reflective mirror and the laser beam reflected by the spectroscope, and the laser beam is reflected to the second receiving device. According to the technical scheme provided by the invention, signals are respectively obtained on the two receiving devices in a double-mirror turn-back mode, strong and weak echoes are distinguished, the dynamic range of measurement is improved, and the detection capability is enhanced.

Description

Technical Field

[0001] The present disclosure relates to the field of laser radar technology, and in particular to a laser radar dual-receiving device and a laser radar. Background Art

[0002] In modern society, lidar has become a standard feature of more and more technologies. In terms of working principle, lidar transmits a detection signal (laser beam) to the target, and then compares the received signal reflected from the target (target echo) with the transmitted signal. After appropriate processing, it can obtain relevant information about the target, such as target distance, direction, altitude, speed, attitude, and even shape parameters, thereby detecting, tracking and identifying targets such as aircraft and missiles.

[0003] Generally, at the receiving end of the laser radar, the optical signal is calibrated by the optical system and then received by the photodetector. Light of different energy intensities generates currents of different intensities in the detector, which are then amplified and processed by the back-end amplifier to obtain echo signals of different amplitudes. However, when the detection object is close and the received light is strong, or when the detection object is far away but its reflectivity is strong, it is easy to cause the amplifier signal to be oversaturated, the waveform to be clipped and distorted, and the recovery time is long. When the detection object is far away and the received light is weak, or when the detection object is close but its reflectivity is weak, the echo signal amplitude is low, and the signal is easily ignored in the noise background, resulting in information loss. Summary of the invention

[0004] The present disclosure provides a dual-receiving laser radar device to at least solve the problem of overcoming signal saturation or low signal amplitude in the related art and improve the dynamic range of measurement. The technical solution of the present disclosure is as follows:

[0005] According to a first aspect of an embodiment of the present disclosure, a laser radar dual receiving device is provided, comprising a beam splitter (1), a total reflector (2), a first receiving device (3) and a second receiving device (4);

[0006] The beam splitter (1) is arranged in front of the first receiving device (3) and forms a first preset angle with the laser beam. The beam splitter (1) is used to split the laser beam into two paths, one path is transmitted to the first receiving device (3), and the other path is reflected to the total reflection mirror (2); the total reflection mirror (2) is arranged in front of the second receiving device (4), and the total reflection mirror (2) forms a second preset angle with the laser beam reflected by the beam splitter (1), and reflects the laser beam to the second receiving device (4).

[0007] In a possible implementation, the first receiving device (3) comprises a first photodetector, and the first photodetector is used to receive the transmitted light of the beam splitter (1).

[0008] In a possible implementation, the second receiving device (4) comprises a second photodetector, and the second photodetector is used to receive the reflected light of the total reflective mirror (2).

[0009] In a possible implementation, the first receiving device (3) further includes a first amplifier circuit, and the second receiving device (4) further includes a second amplifier circuit, and the first amplifier circuit and the second amplifier circuit are amplifier circuits with the same gain.

[0010] In a possible implementation manner, the reflectivity of the beam splitter (1) is greater than its transmittance.

[0011] In a possible implementation manner, the first photodetector and the second photodetector include one or more of an avalanche photodiode, a single photon avalanche diode, or a silicon photomultiplier tube.

[0012] According to a second aspect of an embodiment of the present disclosure, a laser radar is provided, comprising a laser radar dual-receiving device as described above, and also comprising a laser emitting device (5), wherein the laser emitting device (5) comprises a laser and a circuit substrate, and the laser emitting device (5) is used to emit the laser light beam.

[0013] In a possible implementation, the device further comprises a folding mirror (6), wherein the folding mirror (6) is located in front of the laser emitting device (5) and is used to reflect the laser beam twice.

[0014] In a possible implementation, the device further comprises a receiving lens barrel (7) and a transmitting lens barrel (8), and the laser beam enters the receiving lens barrel (7) and the transmitting lens barrel (8) vertically.

[0015] In a possible implementation, the device further includes an optical lens group, a base, and a rotating platform; the optical lens group is located on the light transmission and receiving path and is used to adjust the light path; the laser emitting device (5), the optical lens group, and the laser radar dual receiving device are all arranged on the rotating platform.

[0016] The technical solution provided by the embodiments of the present disclosure brings at least the following beneficial effects: the laser radar receiving device is provided with a beam splitter, a total reflector, a first receiving device and a second receiving device; the beam splitter is arranged in front of the first receiving device and is at a preset angle with the laser beam, and the beam splitter is used to split the laser beam into two paths, one path is transmitted to the first receiving device, and the other path is reflected to the total reflector; the total reflector is arranged in front of the second receiving device, and the total reflector is at a preset angle with the laser beam reflected by the beam splitter, and reflects the laser beam to the second receiving device. By adopting the beam splitter and the total reflector to return, the signals of the laser beam are obtained on the first and second receiving devices respectively, the strong and weak echoes are distinguished, the dynamic range of the measurement is improved, and the detection capability is enhanced.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the description are used to explain the principles of the present disclosure, and do not constitute improper limitations on the present disclosure.

[0019] Figure 1 is a schematic diagram of a laser radar dual-receiving device according to an exemplary embodiment;

[0020] Figure 2 is a schematic diagram of a laser radar according to an exemplary embodiment.

[0021] Among them, the reference numerals in the figure should be: 1-beam splitter, 2-total reflecting mirror, 3-first receiving device, 4-second receiving device, 5-laser emitting device, 6-returning mirror, 7-receiving lens barrel, 8-emitting lens barrel. DETAILED DESCRIPTION

[0022] In order to enable ordinary persons in the art to better understand the technical solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0024] See also Figure 1 , Figure 1 The invention is a schematic diagram of a laser radar dual receiving device according to an exemplary embodiment; the laser radar dual receiving device comprises a beam splitter (1), a total reflector (2), a first receiving device (3) and a second receiving device (4); the beam splitter (1) is arranged in front of the first receiving device (3) and forms a first preset angle with the laser beam, and the beam splitter (1) is used to split the laser beam into two paths, one of which is transmitted to the first receiving device (3) and the other is reflected to the total reflector (2); the total reflector (2) is arranged in front of the second receiving device (4), and the total reflector (2) forms a second preset angle with the laser beam reflected by the beam splitter (1), and reflects the laser beam to the second receiving device (4).

[0025] In the embodiments of this specification, the first receiving device and the second receiving device may refer to devices capable of receiving a laser beam and generating a corresponding echo signal.

[0026] In the embodiments of the present specification, the beam splitter (1) may refer to an optical device that can split a beam of light into multiple beams. For example, it may be an optical device that transmits a portion of a beam of light and reflects a portion of the beam of light. Specifically, the beam splitter (1) may be a beam splitter with a reflectivity of 90% and a transmittance of 10%, a reflectivity of 88% and a transmittance of 12%, or a reflectivity of 85% and a transmittance of 15%. The present application does not impose any limitation on this.

[0027] In the embodiments of this specification, the total reflection mirror (2) may refer to an optical device that can cause total reflection of incident light.

[0028] In the embodiments of this specification, the first preset angle may refer to any angle that can transmit part of the laser beam to the first receiving device (3) and reflect part of the laser beam onto the total reflection mirror (2). For example, it may be 30 degrees, 45 degrees or 60 degrees, and this application does not limit this.

[0029] In the embodiments of the present specification, the second preset angle may refer to any angle capable of receiving the laser beam reflected by the beam splitter (2) and reflecting the laser beam to the second receiving device (4). For example, it may be 30 degrees, 45 degrees or 60 degrees, and the present application does not impose any limitation on this.

[0030] In the embodiments of this specification, the spectroscope (1) is arranged in front of the first receiving device (3), and can be 1 cm, 3 cm or 5 cm, etc., and this application does not limit this.

[0031] In the embodiments of this specification, the total reflective mirror (2) is arranged in front of the second receiving device (4), and can be 1 cm, 3 cm or 5 cm, etc., and this application does not limit this.

[0032] In a possible implementation, the beam splitter (1) is arranged in front of the first receiving device (3) and at a preset angle with the laser beam, so that a portion of the laser beam can be received by the first receiving device (3) after passing through the beam splitter.

[0033] In a possible implementation, the total reflection mirror (2) is arranged in front of the second receiving device (4), and the total reflection mirror (2) and the laser beam reflected by the beam splitter (1) are at a preset angle, so that the laser beam can enter the total reflection mirror (2) after being reflected by the beam splitter (1), and be received by the second receiving device (4) after being reflected again by the total reflection mirror (2).

[0034] A strong laser beam is reflected by the beam splitter (1) and the total reflector (2) and enters the second receiving device (4), and the echo signal may be oversaturated, while the laser beam transmitted by the beam splitter (1) reaches the first receiving device (3) after attenuation, and the echo signal will not be oversaturated; a weak laser beam is reflected by the beam splitter (1) and the total reflector (2), and most of it can enter the second receiving device (4). It should be noted that the strong and weak laser beams here do not represent the distance of the object to be measured, and the comprehensive detection distance and the reflectivity of the object to be measured need to be considered. Taking a spectroscope with a reflectivity of 90% and a transmittance of 10% as an example, there are four situations: at a close distance, when the object to be measured has a strong reflectivity, the echo signal at this time should be extremely strong, so the echo signal of the first receiving device after 10% transmission of the spectroscope is selected; at a close distance, when the object to be measured has a weak reflectivity, a non-saturated echo signal with a larger amplitude is selected from the echo signals of the two receiving devices; at a long distance, when the object to be measured has a weak reflectivity, the echo signal at this time is weak, and the echo signal of the second receiving device after 90% reflection of the spectroscope is selected; at a long distance, when the object to be measured has a strong reflectivity, a non-saturated echo signal with a larger amplitude is selected from the echo signals of the two receiving devices.

[0035] The first receiving device receives the strong light attenuated by the beam splitter, and the second receiving device receives the weak light reflected by the beam splitter and the total reflector. This device receives strong and weak light with different receiving devices, distinguishes between strong and weak echoes, and improves the detection capability and dynamic detection range of the lidar system.

[0036] The first receiving device (3) comprises a first photodetector, and the first photodetector is used to receive the transmitted light of the spectroscope (1).

[0037] In the embodiments of this specification, the first photodetector may refer to a component that can convert an optical signal into an electrical signal. For example, the first photodetector may include but is not limited to an avalanche photodiode, a single photon avalanche diode, or a silicon photomultiplier tube.

[0038] The strong laser beam is reflected by the beam splitter and the total reflection mirror into the second photodetector, and the echo signal may be oversaturated. However, the laser beam transmitted by the beam splitter reaches the first photodetector after transmission attenuation, and the echo signal will not be oversaturated.

[0039] The second receiving device (4) comprises a second photodetector, and the second photodetector is used to receive the reflected light of the total reflection mirror (2).

[0040] In the embodiments of this specification, the second photodetector may refer to a component that can convert an optical signal into an electrical signal. For example, the second photodetector may include but is not limited to an avalanche photodiode, a single photon avalanche diode, or a silicon photomultiplier tube.

[0041] The weak laser beam is reflected by the beam splitter and the total reflection mirror, and most of it can enter the second photodetector.

[0042] The first receiving device (3) further comprises a first amplifier circuit, and the second receiving device (4) further comprises a second amplifier circuit, wherein the first amplifier circuit and the second amplifier circuit are amplifier circuits with the same gain.

[0043] In a possible implementation, the first amplifying circuit is located at the rear end of the first photodetector, and the second amplifying circuit is located at the rear end of the second photodetector.

[0044] By amplifying the circuit with the same gain, echo signals of different distances and light intensities can be distinguished, thereby improving the dynamic range of the measurement.

[0045] The reflectivity of the beam splitter (1) is greater than its transmittance.

[0046] The first photodetector and the second photodetector include one or more of an avalanche photodiode, a single photon avalanche diode or a silicon photomultiplier tube.

[0047] See also Figure 2 , Figure 2 is a schematic diagram of a laser radar according to an exemplary embodiment;

[0048] A laser radar comprises a laser radar dual-receiving device as described in an embodiment of the present application, and also comprises a laser emitting device (5), wherein the laser emitting device (5) comprises a laser and a circuit substrate, and the laser emitting device (5) is used to emit the laser beam.

[0049] In a possible implementation, the laser emitting device includes a laser and a circuit substrate of a laser driving circuit.

[0050] The laser emitting device plays the role of emitting laser beams in the laser radar. After the beam encounters the detection target, it is diffusely reflected and returned to the laser radar receiving device. The received signal is processed by the signal processing unit to obtain information such as the distance, height, and shape of the object being measured.

[0051] The device also includes a folding mirror (6), which is located in front of the laser emitting device (5) and is used to reflect the laser beam twice.

[0052] By setting up a double-reflecting mirror, the symmetrical light path can ensure that the light path for receiving and transmitting is consistent, which is conducive to concentrating energy and the received light spot will be smaller.

[0053] The device also includes a receiving lens barrel (7) and a transmitting lens barrel (8), and the laser beam enters the receiving lens barrel (7) and the transmitting lens barrel (8) vertically.

[0054] The device also includes an optical lens group, a base and a rotating platform; the optical lens group is located on the light-receiving and light-emitting path and is used to adjust the light path; the laser emitting device (5), the optical lens group and the laser radar dual receiving device are all arranged on the rotating platform.

[0055] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0056] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

[0057] It should be noted that the embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used in this article is intended to best explain the principles of the embodiments, practical applications or technical improvements in the market, or to enable other ordinary skill in the art to understand the embodiments disclosed herein.

[0058] It should be noted that the above-mentioned sequence of the embodiments of the present application is for description only and does not represent the advantages and disadvantages of the embodiments. The above-mentioned specific embodiments of this specification are described. Other embodiments are within the scope of the attached claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0059] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A laser radar dual receiving device, characterized in that: It comprises a beam splitter (1), a total reflection mirror (2), a first receiving device (3) and a second receiving device (4); The beam splitter (1) is arranged in front of the first receiving device (3) and forms a first preset angle with the laser beam. The beam splitter (1) is used to split the laser beam into two paths, one path is transmitted to the first receiving device (3), and the other path is reflected to the total reflection mirror (2); the total reflection mirror (2) is arranged in front of the second receiving device (4), and the total reflection mirror (2) forms a second preset angle with the laser beam reflected by the beam splitter (1), and reflects the laser beam to the second receiving device (4).

2. The laser radar dual receiving device according to claim 1, characterized in that: The first receiving device (3) comprises a first photodetector, and the first photodetector is used to receive the transmitted light of the spectroscope (1).

3. The laser radar dual receiving device according to claim 2, characterized in that: The second receiving device (4) comprises a second photodetector, and the second photodetector is used to receive the reflected light of the total reflection mirror (2).

4. The laser radar dual receiving device according to claim 2, characterized in that: The first receiving device (3) further comprises a first amplifier circuit, and the second receiving device (4) further comprises a second amplifier circuit, wherein the first amplifier circuit and the second amplifier circuit are amplifier circuits with the same gain.

5. The laser radar dual receiving device according to claim 1, characterized in that: The reflectivity of the beam splitter (1) is greater than its transmittance.

6. The laser radar dual receiving device according to claim 3, characterized in that: The first photodetector and the second photodetector include one or more of an avalanche photodiode, a single photon avalanche diode or a silicon photomultiplier tube.

7. A laser radar, characterized in that: It comprises a laser radar dual-receiving device as described in any one of claims 1 to 6, and also comprises a laser emitting device (5), wherein the laser emitting device (5) comprises a laser and a circuit substrate, and the laser emitting device (5) is used to emit the laser light beam.

8. The laser radar according to claim 7, characterized in that: The device also includes a folding mirror (6), which is located in front of the laser emitting device (5) and is used to reflect the laser beam twice.

9. The laser radar according to claim 7, characterized in that: The device also includes a receiving lens barrel (7) and a transmitting lens barrel (8), and the laser beam enters the receiving lens barrel (7) and the transmitting lens barrel (8) vertically.

10. A laser radar according to claim 7, characterized in that: The device also includes an optical lens group, a base and a rotating platform; the optical lens group is located on the light-receiving and light-emitting path and is used to adjust the light path; the laser emitting device (5), the optical lens group and the laser radar dual receiving device are all arranged on the rotating platform.

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