WO2020001372A1

WO2020001372A1 - Coaxial transmitting-receiving detection device

Info

Publication number: WO2020001372A1
Application number: PCT/CN2019/092169
Authority: WO
Inventors: 杜晨光
Original assignee: 洛伦兹（北京）科技有限公司
Priority date: 2018-06-26
Filing date: 2019-06-21
Publication date: 2020-01-02
Also published as: CN109000584A

Abstract

A coaxial transmitting-receiving detection device ensures high matching between a transmitting visual field and a receiving visual field using a simplified structure, can receive more return light, and increases a signal-to-noise ratio and a detection distance; and at the same time, the various parts of said device are connected by means of optical fibers, facilitating flexible installation.

Description

Coaxial transmission and reception detection device

Technical field

The invention relates to the field of detection, in particular to a coaxial transmission and reception detection device.

Background technique

In many applications such as aerospace, profiling, machine vision, autonomous vehicles, and drones, three-dimensional contour information of objects and environments is required. With the development of technology, higher and higher requirements are imposed on environmental perception.

Photoelectric detection, as an important means to realize three-dimensional contour sensing, has received more and more attention in recent years, and has also made great progress. Commonly used photoelectric detection techniques mainly include Moire fringe method, triangulation method, pulse time flight method, indirect time flight method, laser illumination distance gated imaging method, etc. The above-mentioned technical approaches have their own advantages and disadvantages, and have been practically applied in different platforms and fields.

In the current photoelectric detection, the emission aperture and the reception aperture of most light sources are separated, that is, most of them are non-coaxial transmission and reception, which not only increases the difficulty of scanning the beam, but also leads to inefficient calibration of the optical axis during production. To solve this problem, some coaxial transmission and reception solutions have also appeared, such as the use of polarizing prisms, fiber circulators, and so on.

Taking the polarization prism solution shown in FIG. 1 as an example, the solution is implemented by a half mirror 115. Its disadvantages are: the system structure is more complicated, and it requires two sets of lenses: the transflective mirror 115 and the receiver 140; when the light beam emitted by the light source 110 passes through the transflective mirror 115, it has both transmission and reflection, and it will lose some energy. When receiving the return beam, when passing through the transflective mirror 115, there is both transmission and reflection, and a part of energy is lost, so only part of the energy reaches the receiving system, the signal to noise is low, and the detection distance is limited.

Summary of the invention

An embodiment of the present invention provides a coaxial transmission and reception detection device. In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not a general overview, nor is it intended to identify key / important constituent elements or to describe the scope of protection of these embodiments. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

An embodiment of the present invention provides a coaxial transmission / reception detection device, which includes: a processor, a laser, a coaxial transceiver, a receiver, and a transmission / reception scanner;

The processor is configured to control the laser to emit laser light; process a signal obtained by the receiver;

The transceiver scanner is configured to emit the laser light to the object to be measured in a scanning manner; and to receive the return light of the laser beam through the object to be measured;

The coaxial transceiver is configured to receive the laser light via a transmitting optical fiber, and transmit the laser light to the transceiving scanner via a transceiving optical fiber; receive the return light transmitted by the transceiving scanner via the transceiving optical fiber, Transmitting the returning light to the receiver via a receiving fiber;

The receiver is configured to receive the return light and convert it into an electrical signal.

Based on the device, as an optional first embodiment, the device further includes: an optical fiber beam splitter;

The optical fiber beam splitter is configured to divide the laser light into at least two light beams, and each light beam corresponds to a detection path;

Each of the detection paths includes: at least one of the coaxial transceiver, at least one of the receiver, and at least one of the transceiving scanner.

Based on the device and the first embodiment, as an optional second embodiment, the transceiving scanner includes: a collimating member, a reflective beam deflection device array, and a transmissive beam deflection device array;

The reflective beam deflection device array includes at least one reflective beam deflection device for reflecting the laser light to the transmissive beam deflection device array; receiving the return light from the transmissive beam deflection device array;

The transmission-type beam deflecting device array includes at least one transmission-type beam deflecting device for transmitting the laser light to the object to be measured; receiving the return light;

The collimating member is provided at least one place between the transmitting and receiving optical fiber and the reflective beam deflection device, and between the reflective beam deflection device and the transmission beam deflection device.

Based on the device and the first embodiment, as an optional third embodiment, the transceiving scanner includes: a collimating member and a reflective beam deflection device array;

The reflective beam deflection device array includes at least one reflective beam deflection device for reflecting the laser light to the object to be measured; receiving the return light;

The collimating member is disposed at least one place between the transceiving fiber and the reflective beam deflection device array, and between the reflective beam deflection device array and the object to be measured.

Based on the device and the first embodiment, as an optional fourth embodiment, the transceiving scanner includes: a collimating member and a transmission beam deflection device array;

The collimating member is disposed between the transceiving optical fiber and the transmissive beam deflecting device array.

Based on the device and the first embodiment, as an optional fourth embodiment, the coaxial transceiver includes: a first optical fiber and a second optical fiber;

The first optical fiber is connected to the transmitting optical fiber and the transmitting and receiving optical fiber;

The second optical fiber is connected to the receiving optical fiber, and the second optical fiber is disposed next to the first optical fiber;

The first optical fiber is configured to receive laser light through the transmitting optical fiber and transmit the laser light to the transmitting and receiving optical fiber; receive the returning light through the transmitting and receiving optical fiber and couple to the second optical fiber;

The second optical fiber is configured to transmit the returning light to the receiving optical fiber.

Based on the fourth embodiment, as an optional fifth embodiment, the first optical fiber has a cladding and a core, and the return light is coupled to the second optical fiber after transmitting a set distance in the cladding. optical fiber.

Based on the fourth embodiment, as an optional sixth embodiment, the second optical fiber is at least two, is arranged around the first optical fiber, and is disposed close to the first optical fiber.

Based on the sixth embodiment, as an optional seventh embodiment, each of the receiving optical fibers is connected to one of the second optical fibers.

Based on the sixth embodiment, as an optional eighth embodiment, one receiver is connected to at least two of the receiving optical fibers;

One of the coaxial transceivers is connected to at least two of the receiving optical fibers.

Based on the fourth embodiment, as an optional ninth embodiment, parameters of the first optical fiber, the transmitting optical fiber, and the transmitting and receiving optical fiber are matched;

Alternatively, the first optical fiber, the transmitting optical fiber, and the transceiving optical fiber are one optical fiber.

Based on the fourth embodiment, as an optional tenth embodiment, parameters of the second optical fiber and the receiving optical fiber are matched;

Alternatively, the second optical fiber and the receiving optical fiber are one optical fiber.

Based on the device and the first embodiment, as an optional eleventh embodiment, the laser includes a semiconductor laser and an isolator;

A semiconductor laser for generating a pump light; the pump light is used to excite a fiber laser;

The isolator is used to isolate the pump light.

Based on the device and the first embodiment, as an optional twelfth embodiment, the device further includes: a narrowband filter;

The narrowband filter is provided on at least one of the transceiving scanner and the receiver, and has a filtering parameter close to the laser wavelength.

Based on the device and the first embodiment, as an optional thirteenth embodiment, the laser is configured to:

Generating a pulsed laser;

Generating a coded laser signal carrying identification information of the device by measuring the same object to be measured multiple times by using the pulsed laser;

The encoded laser signal is transmitted.

Based on the thirteenth embodiment, as an optional fourteenth embodiment, the receiver is configured to:

Convert all the received return light into electrical signals, and decode the converted electrical signals to determine the electrical signals corresponding to the encoded laser signals emitted by the device.

Based on the device and the first embodiment, as an optional fifteenth embodiment, the device further includes: a temperature sensor and a temperature control component;

The temperature sensor is used to obtain the temperature of the laser and the receiver;

The temperature control component is configured to perform temperature control when a temperature obtained by the temperature sensor exceeds a temperature threshold.

The coaxial transmission and reception detection device in the embodiment of the present invention achieves the following beneficial effects:

First, the structure of the detection device is simplified;

Secondly, the transmitting field of view and the receiving field of view are highly matched, and more return light can be received, which improves the signal-to-noise ratio and detection distance;

Third, all parts of the device are connected by optical fiber, which is convenient for flexible installation.

It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and should not limit the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings herein are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present invention, and together with the description serve to explain the principles of the present invention.

FIG. 1 is a schematic diagram of a coaxial transmission and reception detection device in the prior art; FIG.

2 is a schematic diagram of a coaxial transmission and reception detection device in an exemplary embodiment;

3 is a schematic diagram of a coaxial transmission and reception detection device in an exemplary embodiment;

4 is a schematic diagram of implementation of multi-path detection on a car in an exemplary embodiment;

5 is a schematic structural diagram of a transmitting and receiving scanner in an exemplary embodiment;

6 is a schematic structural diagram of a transmitting and receiving scanner in an exemplary embodiment;

7 is a schematic structural diagram of a transmitting and receiving scanner in an exemplary embodiment;

8 is a schematic structural diagram of a transmitting and receiving scanner in an exemplary embodiment;

9a is a schematic diagram of performing one-dimensional scanning in one direction in an exemplary embodiment;

9b is a schematic diagram of two-dimensional scanning in two directions in an exemplary embodiment;

10 is a schematic structural diagram of a coaxial transceiver in an exemplary embodiment;

11 is a schematic structural diagram of a laser in an exemplary embodiment;

FIG. 12 is a schematic diagram of pulse lasers with different pulse widths in an exemplary embodiment; FIG.

FIG. 13 is a schematic diagram of the intensity of return light in an exemplary embodiment.

detailed description

The following description and the drawings sufficiently illustrate specific embodiments of the present invention to enable those skilled in the art to practice them. The examples represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of embodiments of the invention includes the entire scope of the claims, and all available equivalents of the claims. Herein, the embodiments may be individually or collectively represented by the term "invention", this is for convenience only, and if more than one invention is actually disclosed, it is not intended to automatically limit the scope of the application to any A single invention or inventive idea. In this article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not require or imply any actual relationship between these entities or operations or order. Moreover, the terms "including," "including," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed Elements. The embodiments in this document are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same and similar parts between the embodiments, refer to each other.

In an exemplary embodiment, as shown in FIG. 2, the coaxial transmission / reception detection device includes a processor 11, a laser 12, a coaxial transceiver 13, a receiver 14, and a transceiver scanner 15.

The processor 11 is configured to control the laser 12 to emit laser light and process signals obtained by the receiver 14.

The transceiving scanner 15 is configured to emit the laser light to the object to be measured in a scanning manner; and receive the return light of the laser light through the object to be measured.

The coaxial transceiver 13 is configured to receive the laser light through the transmitting optical fiber 6, and transmit the laser light to the transmitting and receiving scanner 15 through the transmitting and receiving optical fiber 8; The receiving fiber 7 transmits the return light to the receiver 14.

The receiver 14 is configured to receive the returned light and convert it into an electrical signal.

Considering the actual application environment, the detection device can be divided into an internal installation portion 100 and an external installation portion 200, and the above-mentioned components can be respectively included in these two parts.

The coaxial transmission and reception detection device in this exemplary embodiment achieves the following beneficial effects:

First, the structure of the detection device is simplified;

In an exemplary embodiment, as shown in FIG. 3, the coaxial transmission / reception detection device includes a processor 11, a laser 12, a coaxial transceiver 13, a receiver 14, a transmission / reception scanner 15, and a fiber optic beam splitter 16.

The optical fiber beam splitter 16 is configured to divide the laser light emitted by the laser 12 into at least two light beams, and each light beam corresponds to a detection path.

The detection path includes: at least one coaxial transceiver 13, at least one receiver 14, and at least one transceiving scanner 15. It can be seen that there are multiple combinations of devices included in the detection path. For example, a detection path may include a coaxial transceiver 13, a receiver 14, and a transceiving scanner 15. For example, a detection path may include a coaxial transceiver 13. , Multiple receivers 14 and a transceiving scanner 15. Optionally, one transmitting / receiving scanner 15 may belong to multiple detection paths. In this case, one transmitting / receiving scanner 15 may be connected to multiple coaxial transceivers 13 through multiple transmitting / receiving optical fibers 8.

The processor 11 includes a controller and at least one signal processor. The controller is configured to control the laser 12 to emit laser light, and the signal processor is configured to process signals obtained by the receiver 14. Optionally, each of the signal processors may process signals obtained by one or more receivers 14.

The coaxial transceiver 13 is configured to receive the laser light through the transmitting optical fiber 6 and transmit the laser light to the transmitting and receiving scanner 15 via the transmitting and receiving optical fiber 8; receive the return light transmitted from the transmitting and receiving scanner 15 through the transmitting and receiving optical fiber 8 and The receiving fiber 7 transmits the return light to the receiver 14.

After the optical fiber beam splitter 16 is adopted, one laser beam emitted by the laser 12 can be divided into multiple channels to realize multiple detection, which effectively reduces the cost and reduces the size of the detection device. Each detection path can be flexibly installed in different locations of the application environment to achieve detection in different areas.

As shown in FIG. 4, taking the application environment as the car 300 as an example, each of the above detection paths can be installed in different positions of the car. The head position is provided with two transmitting and receiving scanners 15 in parallel, one for a small field of view at a long distance and one for a large field of view at a short distance. Several transceiving scanners 15 may also be provided in the vehicle side and rear.

In an exemplary embodiment, the internal structure of the transceiving scanner 15 includes a collimating component, and may further include at least one of a reflective beam deflecting device array and a transmissive beam deflecting device array.

The reflection type light beam deflection device refers to a device that changes the propagation direction of a light beam when the reflection angle of the reflection surface of the device changes, and when a light beam is irradiated and reflected thereon.

The reflective beam deflecting device array may include at least one reflective beam deflecting device. The reflective beam deflecting device may be a MEMS galvanometer, a rotating mirror, a galvanometer, or other mirrors. When multiple reflective beam deflecting devices are included, Multiple reflective beam deflection devices are connected in series.

The transmission type light beam deflection device refers to a device that changes the direction of propagation of a light beam when the light beam passes through the device by adjusting an electrical signal applied to the device.

The transmission beam deflection device array may include at least one transmission beam deflection device. The transmission beam deflection device may be an electro-optic device, an acousto-optic device, a liquid crystal device, or a phased array device. In this case, a plurality of transmission type beam deflecting devices are connected in series.

Several examples of the internal structure of the transceiver scanner 15 are given below.

As shown in FIG. 5, the transmitting and receiving scanner 15 includes a collimating member 41, a reflective beam deflecting device array, and a transmissive beam deflecting device array.

The transmission-type beam deflecting device array includes a plurality of transmission-type beam deflecting devices 43 arranged in series.

The reflective beam deflecting device array includes a reflective beam deflecting device 42 for reflecting the laser light emitted by the laser 12 to the transmissive beam deflecting device 43; and receiving return light from the transmissive beam deflecting device 43.

The collimating member 41 is provided between the transmission / reception optical fiber 8 and the reflective beam deflecting device 42, and between the reflective beam deflecting device 42 and the transmission beam deflecting device 43. In some application scenarios, the collimating component 41 may be disposed between the transmitting and receiving optical fiber 8 and the reflective beam deflecting device 42 or between the reflective beam deflecting device 42 and the transmissive beam deflecting device 43.

As an optional implementation manner, the collimating member 41 may be a lens group, and plays a role of collimating and condensing light.

As an optional implementation manner, the transmission array may include only one transmission-type beam deflecting device 43.

The transmitting / receiving scanner 15 implements at least one of the reflective beam deflection device 42 and the transmissive beam deflection device 43 to transmit the laser light emitted by the laser 12 to the object to be measured in a scanning manner.

As shown in FIG. 6, the transmitting and receiving scanner 15 includes a collimating part 51, a reflective beam deflecting device array, and a transmissive beam deflecting device array.

The transmission-type beam deflecting device array includes a plurality of transmission-type beam deflecting devices 53 arranged in series.

The reflective beam deflecting device array includes a first reflective beam deflecting device 521 and a second reflective beam deflecting device 522. The first reflective beam deflecting device 521 is configured to reflect the laser light emitted by the laser 12 to the second reflective beam deflecting device 522; and receive the return light from the second reflective beam deflecting device 522.

The second reflective beam deflecting device 522 is configured to reflect the laser light emitted by the laser 12 to the transmissive beam deflecting device 53; and receive the return light from the transmissive beam deflecting device 53.

The collimating member 51 is provided between the transmitting and receiving optical fiber 8 and the first reflective beam deflecting device 521, and between the second reflective beam deflecting device 522 and the transmissive beam deflecting device 53. In some application scenarios, the collimating component 51 may also be disposed between the transmitting and receiving optical fiber 8 and the first reflective beam deflection device 521, or between the second reflective beam deflection device 522 and the transmissive beam deflection device 53. one place.

As an optional implementation manner, the structure shown in FIG. 7 may not include a transmission array, and the reflective array directly emits the laser light to the object to be measured, and then directly receives the laser light returning through the object to be measured.

As an optional implementation manner, in the structure shown in FIG. 7, the transmission-type beam deflecting device array may include only one transmission-type beam deflecting device 53.

As shown in FIG. 7, the transceiving scanner 15 includes a collimating part 61 and a reflective beam deflection device array.

The reflective beam deflecting device array includes a reflective beam deflecting device 62 for reflecting the laser light emitted by the laser 12 to the object to be measured; receiving the return light of the laser light through the object to be measured and reflecting it to the transceiver fiber 8.

The collimating member 61 is provided between the transmitting and receiving optical fiber 8 and the reflective beam deflecting device 62 and between the reflective beam deflecting device 62 and the object to be measured.

As shown in FIG. 8, the transmitting and receiving scanner 15 includes a collimating member 71 and a transmission type beam deflecting device array.

The transmissive beam deflecting device array includes a plurality of transmissive beam deflecting devices 72 arranged in series.

A collimation member 71 is provided between the transmission / reception fiber 8 and the transmission beam deflection device 72.

As an optional implementation manner, the transmission-type beam deflecting device array may include only one transmission-type beam deflecting device 72.

Based on any one of the structure of the transceiver scanner 15 shown in FIGS. 5 to 8, one transceiver scanner 15 can be connected to at least two transceiver fibers 8. When the transceiving scanner 15 is connected to a plurality of transceiving optical fibers 8, the transmitting energy can be increased, and the spot of the received return light is larger, thereby collecting more energy and improving the sensitivity of the detection device.

Based on any structure of the transceiving scanner 15 shown in Figs. 5 to 8, the transceiving scanner 15 can perform one-dimensional scanning in one direction, such as scanning in the horizontal or vertical direction, as shown in Fig. 9a. A two-dimensional scan, such as a snake scan, can be performed in two directions as shown in FIG. 9b.

Based on any one of the structure of the transmitting and receiving scanner 15 shown in FIG. 5 to FIG. 8, the transmitting and receiving scanner 15 has different angle ranges, scanning intervals, and scanning speeds, and realizes dynamic changes of the detection angular range, angular resolution, and detection speed. Two examples are given below.

On highways, vehicles travel faster, and forward detection requires detection at a longer distance. Detection can be concentrated within a set angle range directly in front of the vehicle. At this time, the transceiver scanner 15 can perform non-waiting according to the set parameters. The angularly spaced non-uniform speed scanning mainly focuses the scanning within a set angle range directly in front of the vehicle. In the downtown area, vehicles are running slowly and the traffic conditions are complicated. The forward detection needs to cover a large angular range. At this time, the transceiver scanner 15 can perform uniform speed scanning at equal angular intervals.

In other application scenarios, the above-mentioned equiangular interval scanning, non-equal angular interval scanning, uniform scanning and non-uniform scanning can also be used in other combinations.

In an exemplary embodiment, as shown in FIG. 10, the coaxial transceiver 13 shown in FIG. 2 or FIG. 3 includes a first optical fiber 91 and a second optical fiber 92.

The first optical fiber 91 is connected to the transmitting optical fiber 6 and the transmitting and receiving optical fiber 8. Optionally, the first optical fiber 91, the transmitting optical fiber 6, and the transmitting and receiving optical fiber 8 have a cladding and a core.

The second optical fiber 92 is connected to the receiving optical fiber 7, and the second optical fiber 92 is disposed next to the first optical fiber 91. The immediate setting can be a snug fit.

The returning light passing through the object to be measured reaches the first optical fiber 91 from the transmitting and receiving optical fiber 8, and is transmitted to the second optical fiber 92 after transmitting a set distance in the cladding of the first optical fiber 91. The return light coupled to the second optical fiber 92 may vary depending on the coupling efficiency.

As an optional implementation manner, the parameters of the first optical fiber 91, the transmitting optical fiber 6, and the transmitting and receiving optical fiber 8 match, or the first optical fiber 91, the transmitting optical fiber 6, and the transmitting and receiving optical fiber 8 may be one optical fiber, and the optical fiber may be a single-mode optical fiber or Double-clad fiber. The parameters of the second optical fiber 92 and the receiving optical fiber 7 match, or the second optical fiber 92 and the receiving optical fiber 7 may be one optical fiber, and the optical fiber may be an unclad quartz wire.

Based on the structure shown in FIG. 10, the coaxial transceiver 13 can realize efficient separation of transmission and reception. After the laser transmitted from the transmitting optical fiber 6 reaches the coaxial transceiver 13, it will enter a large or all of the receiving optical fiber 8. After the return light transmitted from the transmitting optical fiber 8 reaches the coaxial transceiver 13, it will be coupled into the receiving optical fiber in large or all. 7 in.

As an optional implementation manner, the second optical fiber 92 may be at least two, which surrounds the first optical fiber 91 and is disposed immediately adjacent to the first optical fiber 91.

As an optional implementation manner, the number of the second optical fibers 92 and the receiving optical fibers 7 is the same. Further, one receiver 14 may be connected to at least two receiving optical fibers 7, and one coaxial transceiver 13 may be connected to at least two receiving optical fibers 7.

In an exemplary embodiment, the laser 12 may be a fiber laser, or other lasers with fiber-coupled output. As shown in FIG. 11, when the laser 12 includes a semiconductor laser 101, the laser 12 may further include an isolator 102.

A semiconductor laser 101 is used to emit pump light. The pump light is used to excite the fiber laser.

An isolator 102 is used to isolate the pump light. The isolator 102 achieves the isolation of the pump light, leaving only the fiber laser useful for subsequent detection.

In an exemplary embodiment, the device shown in FIG. 2 or FIG. 3 may further include a narrow-band filter disposed on at least one of the transceiving scanner 15 and the receiver 14. The aforementioned narrowband filter has filtering parameters close to the wavelength of the laser light emitted by the laser 12, so that only return light near the wavelength of the emitted laser light is allowed to pass, and ambient background light of other wavelengths is filtered out, which can improve the signal-to-noise ratio of the detection device. Optionally, the narrow-band filter may be an OD3 to 5 filter.

In an exemplary embodiment, the complete detection of the object to be measured is achieved by scanning different positions of the surface of the object to be measured with a pulsed laser. The scanning for each scanning position is referred to as a detection, and each detection is performed using a multi-pulse laser. . In this case, the laser 12 generates a pulsed laser, and the pulsed laser is used to measure the same target multiple times to generate a coded laser signal that carries identification information of the detection device, and then transmits the coded laser signal.

The receiver 14 receives the return light passing through the surface of the object to be measured, converts it into an electrical signal, and then decodes it according to the same preset encoding method to obtain the identification information therein, thereby determining the code corresponding to the emission of the device. The electrical signal of the laser signal before performing subsequent operations. It can be seen that each detection through multiple pulses can distinguish the detection device from other detection devices, and improve the anti-interference ability.

In an exemplary embodiment, the receiver 14 may be a single point, linear array, area array, or the like. The receiver 14 may use a charge-coupled device (CCD), a complementary metal oxide semiconductor (CMOS), a position sensitive detector (PSD), a position sensitive detector (PSD), Avalanche PhotoDiode (APD), Photodiode Intrinsic-Negative (PIN), Silicon Photo Multiplier (SiPM), Multi-Pixel Photon Counter English abbreviation MPPC) or other light receiving devices. Make full use of the photoelectric conversion capability, response frequency, resolution, gray level and other parameters of the receiver 14 to achieve high frame rate and high resolution measurement. Based on the application scenario, the receiver 14 may use a single-point APD detector, or a SiPM or MPPC detector.

In an exemplary embodiment, the laser 12 emits a pulsed laser, and the detection device may further include an electronic shutter and a synchronization controller.

Synchronization controller, used to control the synchronization of pulsed laser and electronic shutter.

An electronic shutter is used to control the exposure time of the receiver 14.

The synchronization controller controls the electronic shutter to synchronize with the pulsed laser, and the electronic shutter controls the exposure time of the receiver 14, which can reduce the influence of noise, increase the detection signal-to-noise ratio, and help achieve a longer detection distance.

Optionally, the synchronization controller controls the electronic shutter to synchronize with the pulsed laser, which may not be absolute synchronization. Specifically, the synchronization controller may determine the synchronization time window according to the flight time of the light beam.

In an exemplary embodiment, the complete detection of the object to be measured is achieved by scanning different positions of the surface of the object to be measured with a pulsed laser. The scanning for each scanning position is referred to as a detection, and each detection is performed using a multi-pulse laser. .

Further, by measuring the same target multiple times with a pulsed laser, the laser 12 can generate a coded emission signal. The encoded transmission signal carries identification information of the detection device. The coded transmission signal is a light beam, and the identification information of the device is used to indicate the detection device.

After the receiver 14 receives the return light passing through the surface of the object to be measured, it can decode it according to the same preset encoding method to obtain the device identification information therein, and if it is determined that the return light corresponds to the device, then perform subsequent operations. It can be seen that each detection through multiple pulses can make the receiver distinguish this device from other devices and improve the anti-interference ability.

In an exemplary embodiment, a light shielding device may be provided near the receiver 14, and the light shielding device may be an additional light shielding cover or a narrow space in which the receiver 14 is installed. The shading device can prevent stray light from entering the receiver 14 and improve the signal-to-noise ratio.

In an exemplary embodiment, according to the requirements of different application scenarios, by adjusting the power of the light source, that is, by adjusting the power of the laser 12, the dynamic adjustment of the detection distance and the reflectance range of the covered object to be measured is achieved.

For example, for the objects to be measured with the same reflectivity, the power of the laser 12 is larger when it needs to detect a longer distance, and the power of the laser 12 is smaller when it needs to detect a shorter distance. For another example, for the object to be measured at the same distance, when the power of the laser 12 is large, the object with low reflectance can be detected, and when the power of the laser 12 is small, only the object with high reflectance can be detected. Test object. At this time, the processor 11 can determine different application requirements according to the set conditions, and then adjust the power of the laser 12. The above-mentioned setting conditions may be preset judgment conditions, such as a vehicle speed, a detection result of an object to be measured, etc., or may be a manual input instruction of an operator.

For another example, when the ambient background light is too strong, the signal-to-noise ratio received by the receiver 14 will decrease, which will reduce the effective detection distance. When the ambient background light is too weak, it will cause the waste of light energy of the laser 12 and high power consumption. .

The detection device may further include an ambient light sensor, and the processor 11 may adjust the power of the laser 12 according to the detection result of the ambient light by the ambient light sensor.

If the detection device does not include a detection device for ambient light, the processor 11 may also indirectly obtain the condition of the ambient light according to the intensity of the return light received by the receiver 14, and then adjust the power of the laser 12.

Optionally, the detection device may further include a temperature sensor and a temperature control component.

A temperature sensor is used to obtain the temperature of the laser 12 and the receiver 14.

A temperature control component is used to perform temperature control when the temperature obtained by the temperature sensor exceeds a temperature threshold. Optionally, the temperature threshold may include an upper temperature threshold and a lower temperature threshold. Specifically, when the temperature is higher than the upper temperature threshold, the temperature control device is used for cooling and lowering the temperature. When the temperature is lower than the lower temperature threshold, the temperature control device For heating and increasing the temperature.

The processor 11 can control the electronic shutter to adjust the exposure time of the receiver 14 and the pulse width emitted by the laser 12 to implement the power change of the laser 12. As shown in FIG. 12, the laser 12 is caused to emit pulse lasers with different pulse widths in each constant pulse period, that is, each pulse period may have a different duty cycle.

In an exemplary embodiment, the processor 11 may determine the material of the object to be measured according to the intensity of the return light received by the receiver 14, for example, for vehicle driving, it may distinguish between obstacles and roads, distinguish between pedestrians and trees, and identify Shoulders and lane lanes.

In an exemplary embodiment, the light beam emitted by the laser 12 may be irradiated on certain objects that can be penetrated, such as leaves, glass walls, or other partially transparent objects to be measured, and multiple echo signals are generated. Receive multiple return light and produce multiple imaging results. The intensity of the return light is shown in Figure 13. In this case, the receiver 14 can also be used to receive multiple pulsed laser light returning through the surface of the object to be measured. And imaging. The processor 11 may also be configured to process multiple images and obtain information of the object to be measured.

Specifically, after the receiver 14 receives the first returning light and imaging, the processor 11 can obtain the first measurement result; after the receiver 14 receives the second returning light and imaging, the processor 11 can obtain the second measurement Measurement results; until the last measurement is completed.

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

Claims

A coaxial transmission and reception detection device, characterized in that the device includes: a processor, a laser, a coaxial transceiver, a receiver, and a transceiving scanner;

The processor is configured to control the laser to emit laser light; process a signal obtained by the receiver;

The transceiver scanner is configured to emit the laser light to the object to be measured in a scanning manner; and to receive the return light of the laser beam through the object to be measured;

The coaxial transceiver is configured to receive the laser light via a transmitting optical fiber, and transmit the laser light to the transceiving scanner via a transceiving optical fiber; receive the return light transmitted by the transceiving scanner via the transceiving optical fiber, Transmitting the returning light to the receiver via a receiving fiber;

The receiver is configured to receive the return light and convert it into an electrical signal.
The apparatus according to claim 1, further comprising: an optical fiber beam splitter;

The optical fiber beam splitter is configured to divide the laser light into at least two light beams, and each light beam corresponds to a detection path;

Each of the detection paths includes: at least one of the coaxial transceiver, at least one of the receiver, and at least one of the transceiving scanner.
The apparatus according to claim 1 or 2, wherein the transmitting and receiving scanner comprises: a collimating member, a reflective beam deflecting device array, and a transmissive beam deflecting device array;

The reflective beam deflection device array includes at least one reflective beam deflection device for reflecting the laser light to the transmissive beam deflection device array; receiving the return light from the transmissive beam deflection device array;

The transmission-type beam deflecting device array includes at least one transmission-type beam deflecting device for transmitting the laser light to the object to be measured; receiving the return light;

The collimating member is provided at least one place between the transmitting and receiving optical fiber and the reflective beam deflection device, and between the reflective beam deflection device and the transmission beam deflection device.
The apparatus according to claim 1 or 2, wherein the transceiving scanner comprises: a collimating member and a reflective beam deflection device array;

The reflective beam deflection device array includes at least one reflective beam deflection device for reflecting the laser light to the object to be measured; receiving the return light;

The collimating member is disposed at least one place between the transceiving fiber and the reflective beam deflection device array, and between the reflective beam deflection device array and the object to be measured.
The apparatus according to claim 1 or 2, wherein the transmitting and receiving scanner comprises: a collimating member and a transmission type beam deflecting device array;

The transmission-type beam deflecting device array includes at least one transmission-type beam deflecting device for transmitting the laser light to the object to be measured; receiving the return light;

The collimating member is disposed between the transceiving optical fiber and the transmissive beam deflecting device array.
The apparatus according to claim 1 or 2, wherein the coaxial transceiver comprises: a first optical fiber and a second optical fiber;

The first optical fiber is connected to the transmitting optical fiber and the transmitting and receiving optical fiber;

The second optical fiber is connected to the receiving optical fiber, and the second optical fiber is disposed next to the first optical fiber;

The first optical fiber is configured to receive laser light through the transmitting optical fiber and transmit the laser light to the transmitting and receiving optical fiber;

Receiving the return light through the transceiver fiber, and coupling the return light to the second fiber;

The second optical fiber is configured to transmit the returning light to the receiving optical fiber.
The device according to claim 1 or 2, wherein the laser comprises: a semiconductor laser and an isolator;

A semiconductor laser for generating a pump light; the pump light is used to excite a fiber laser;

The isolator is used to isolate the pump light.
The device according to claim 1 or 2, further comprising: a narrowband filter;

The narrowband filter is provided on at least one of the transceiving scanner and the receiver, and has a filtering parameter close to the laser wavelength.
The apparatus according to claim 1 or 2, wherein the laser is configured to:

Generating a pulsed laser;

Generating a coded laser signal carrying identification information of the device by measuring the same object to be measured multiple times by using the pulsed laser;

The encoded laser signal is transmitted.
The apparatus of claim 9, wherein the receiver is configured to:

Convert all the received return light into electrical signals, and decode the converted electrical signals to determine the electrical signals corresponding to the encoded laser signals emitted by the device.
The device according to claim 1 or 2, further comprising: a temperature sensor and a temperature control component;

The temperature sensor is used to obtain the temperature of the laser and the receiver;

The temperature control component is configured to perform temperature control when a temperature obtained by the temperature sensor exceeds a temperature threshold.