KR102690569B1 - Lidar apparatus using optical synchronization and operating method thereof - Google Patents

Abstract

The present embodiments include a light source that transmits an optical transmission signal, a light detection unit that detects an optical reception signal, which is light reflected by an object located on the scan area among the optical transmission signals, and a light detection unit that receives the optical transmission signal and reflects it toward the scan area, It receives the light reception signal and controls it so that the angle at which the light reception signal is incident on the light detector is constant, and the scanning unit that transmits the light reception signal toward the light detection unit, the transmission reflection unit that determines the scan area, and the incident angle are controlled to be constant. We propose a LIDAR device that includes a synchronization unit that synchronizes the controlling receiving reflector through an optical synchronization method, and a signal processing unit that obtains distance information about the object using the detection result of the light detection unit.

Description

LIDAR device using optical synchronization method and operating method thereof {LIDAR APPARATUS USING OPTICAL SYNCHRONIZATION AND OPERATING METHOD THEREOF}

The present invention relates to a LiDAR device and a method of operating the same using an optical synchronization method. In particular, it relates to a LiDAR device and a method of operating the same that synchronize a transmitting reflector and a receiving reflector using an optical synchronization method.

The content described in this section simply provides background information for this embodiment and does not constitute prior art.

LIDAR (Light Detection and Ranging) irradiates light, such as a laser, to a subject and then analyzes the light reflected from the subject to determine the subject's physical properties, such as distance, direction, speed, temperature, material distribution and concentration. It is one of the remote sensing devices that can measure characteristics, etc.

Conventional LiDAR systems are being developed with the goal of wide scanning angles and high resolution, but as the scanning angle widens to wide angles, the optical system configuration of the receiver and the performance of the laser detector improve the three-dimensional image information measurement distance and spatial resolution of LiDAR. There is a problem that system performance deteriorates. Additionally, conventional LiDAR systems use an array detector to receive light at a wide scan angle, or receive reflected light from a target through rotation. However, the array detector has a longer response time than the single element detector, which shortens the measurement distance and reduces angular resolution, and the rotary type has a reliability problem due to the mechanical drive method.

The main purpose of the embodiments of the present invention is to synchronize the transmitting reflector and the receiving reflector by using a reflecting prism, a laser diode, and a synchronization optical detector to match the optical axis of the optical transmission signal and the optical axis of the optical reception signal.

Other unspecified objects of the present invention can be additionally considered within the scope that can be easily inferred from the following detailed description and its effects.

According to one aspect of this embodiment, the present invention includes a light source that transmits an optical transmission signal; a light detection unit that detects a light reception signal, which is light reflected by an object located on the scan area, among the light transmission signals; Receive the light transmission signal and reflect it toward the scan area, receive the light reception signal and control the angle at which the light reception signal is incident on the light detection unit to be constant, and direct the light reception signal toward the light detection unit. a scanning unit that transmits; a synchronization unit that synchronizes the transmission reflector that determines the scan area and the reception reflector that controls the incident angle to be constant through optical synchronization; and a signal processing unit that obtains distance information about the object using the detection result of the light detection unit.

Preferably, the scanning unit includes: a transmission reflection unit that determines the scan area by performing a tilt drive in a vertical direction; a receiving reflector that is synchronized with the transmit reflector and performs tilt driving at the same angle as the transmit reflector; and a transmission/reception reflection unit that reflects the optical transmission signal reflected and transmitted through the transmission reflection unit toward the object, and reflects the optical reception signal reflected and transmitted through the object to the reception reflection unit.

Preferably, the transmission reflector performs a tilt drive in the vertical direction to adjust the field of view (FOV) in the vertical direction to scan, and the range of the scan angle is determined according to the drive angle, and the initial Tilt driving is performed based on the control value, and the receiving reflector is synchronized with the transmitting reflector by the synchronization unit to perform tilt driving in the vertical direction according to the driving angle.

Preferably, the synchronization unit includes a synchronization light source that transmits an optical synchronization signal for synchronizing the transmission reflector and the reception reflector; a synchronous transmitting and receiving member that converts the optical synchronizing signal into parallel light; a reflecting prism that transmits the optical synchronization signal to the transmission reflector and the reception reflector and transmits the reflection synchronization signal reflected from the transmission reflector and the reception reflector to the synchronization transmission and reception member; and an optical synchronization detection unit that detects the reflection synchronization signal.

Preferably, the synchronization unit is provided between the synchronization light source and the synchronization transmitting and receiving member, and transmits the optical synchronization signal to the synchronizing transmitting and receiving member, and a beam splitter that transmits the reflected synchronization signal to the optical synchronization detection unit. It further includes, wherein the beam splitter controls the reflected synchronization signal received from the synchronization transmitting and receiving member not to be transmitted to the synchronization light source.

Preferably, the reflective prism includes: a first surface that transmits the optical synchronous signal to the transmission reflector as a first optical synchronous signal according to a preset first reflectivity; And a second surface that transmits the optical synchronization signal to the receiving reflector as a second optical synchronization signal according to a preset second reflectance, and the first reflectance and the second reflectance are characterized in that they are implemented differently. .

Preferably, the first reflection synchronization signal from which the first optical synchronization signal incident on the transmission reflector is reflected and returned and the second reflection synchronization signal from which the second optical synchronization signal incident on the reception reflection unit is reflected and returned are: It can be distinguished by amplitude, and the amplitude is characterized by being distinguished by the difference in reflectance of the first surface and the second surface.

Preferably, the reflective prism is spatially divided in half, the reflectance of the first surface is implemented to be higher than the reflectivity of the second surface, and the optical synchronization signal incident on the reflective prism is transmitted from the transmission reflector and In a state where the receiving reflector is unsynchronized, the first reflected synchronization signal incident and reflected by the transmission reflector appears larger than the second reflected synchronization signal incident and reflected by the receiving reflector.

Preferably, the signal processing unit is configured to reduce the time difference occurring between the first reflection synchronization signal and the second reflection synchronization signal when the transmission reflection unit and the reception reflection unit are unsynchronized. It is characterized by controlling the driving frequency of the receiving reflector.

Preferably, the scanning unit includes a transmission member that converts the optical transmission signal into parallel light; and a receiving member provided between the reception reflection unit and the light detection unit, which focuses the light reception signal reflected by the reception reflection unit and transmits it to the light detection unit.

Preferably, the light detection unit is connected to an optical fiber, the light reception signal focused in the receiving member is focused on the optical fiber, and the light reception signal is transmitted through the optical fiber, and the light detection unit is of the InGaAs series. It is characterized by being composed of a PIN type, APD type, or SPAD type.

Preferably, the signal processing unit controls the pulse repetition rate of the light source, the driving angle of the transmission reflector, the driving angle of the reception reflector, the rotation angle of the transmission and reception reflector, or the synchronization unit, and controls the optical transmission signal and the optical reception. It is characterized by calculating distance information about the object through a signal.

In addition, according to another aspect of the present embodiment, the present invention provides a method of operating a LiDAR device by a LiDAR device, including the steps of a synchronization light source transmitting an optical synchronization signal; The first reflection synchronization signal reflected from the transmission reflector and the second reflection synchronization signal reflected from the reception reflector are received by the optical synchronization signal, the driving frequencies of the transmission reflector and the reception reflector are compared, and the transmission synchronizing a reflector and the receiving reflector; When synchronized, driving the transmission/reception reflector to rotate, transmitting an optical transmission signal toward an object through a light source, receiving an optical reception signal through the reception reflection unit, and detecting the optical reception signal through a detection unit; We propose a method of operating a LIDAR device including a step of a signal processing unit acquiring distance information about the object using the detection result of the light detection unit.

As described above, according to the embodiments of the present invention, the present invention uses a transmitting reflector and a receiving reflector to synchronize the transmitting reflector and the receiving reflector so that the optical axes of the optical transmitting signal and the optical receiving signal are aligned to be the same. It has the effect of being able to scan a wide angular range without deteriorating performance.

Even if the effects are not explicitly mentioned here, the effects described in the following specification and their potential effects expected by the technical features of the present invention are treated as if described in the specification of the present invention.

1 to 3 are block diagrams showing a LiDAR device using an optical synchronization method according to an embodiment of the present invention.
Figure 4 is a diagram showing a LIDAR device using an optical synchronization method according to an embodiment of the present invention.
Figure 5 is a diagram showing a reflecting prism of a lidar device using an optical synchronization method according to an embodiment of the present invention.
Figure 6 is a diagram showing a method of synchronizing the transmitting reflector and the receiving reflector of the lidar device using an optical synchronization method according to an embodiment of the present invention.
7 to 9 are flowcharts showing a method of operating a LIDAR device using an optical synchronization method according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely intended to ensure that the disclosure of the present invention is complete and to provide common knowledge in the technical field to which the present invention pertains. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings that can be commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. The singular terms include plural expressions, unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that it does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Terms containing ordinal numbers, such as second, first, etc., may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, the second component may be referred to as the first component without departing from the scope of the present invention, and similarly, the first component may also be referred to as the second component. The term and/or includes any of a plurality of related stated items or a combination of a plurality of related stated items.

The present invention relates to a LiDAR device using an optical interference method and a method of operating the same.

The conventional LiDAR optical system has the advantage of being able to scan a wide area by transmitting and receiving lasers through mechanical rotation, but has problems with mechanical durability. To solve this problem, a mechanical rotating part can be solved using a MEMS mirror, but there is a problem in that the measurement distance is shortened due to the receiver optical system and detector. Therefore, the conventional LiDAR optical system has problems such as a short measurement distance due to the use of a transmitting and receiving optical system and an array detector, a problem with the durability of the system using a mechanical rotating part, an inability to measure short distances within 1 m because the transmitting and receiving optical systems are separated, and a problem with the receiving optical system. There is a problem with scanning distance limitations caused by .

LIDAR (Light Detection and Ranging) can measure the physical properties of an object more precisely by utilizing the advantages of a laser that can generate pulse signals with high energy density and short period. LIDAR uses a laser light source of a specific wavelength or a tunable laser light source as a light source and is used in various fields such as 3D image acquisition, weather observation, measuring the speed or distance of a subject, and autonomous driving. For example, LIDAR is mounted on aircraft and satellites and used for precise atmospheric analysis and observation of the global environment, and is mounted on spacecraft and exploration robots and is used as a means to supplement camera functions such as measuring the distance to a subject.

In addition, simple LiDAR sensor technologies are being commercialized on the ground for long-distance measurement and vehicle speed violation enforcement. Recently, it has been used as a laser scanner or 3D video camera and is being used in 3D reverse engineering and driverless cars.

According to an embodiment of the present invention, the LIDAR device 10 using an optical interference method can be applied to a distance measuring device or a moving object. For example, the LIDAR device 10 can be applied to devices that require distance measurement or moving objects such as drones and cars, but is not necessarily limited thereto. The LiDAR device 10 is a device that shoots a laser signal, measures the time it takes for it to be reflected, and measures the distance to the reflector using the speed of light.

1 to 3 are block diagrams showing a LiDAR device using an optical synchronization method according to an embodiment of the present invention.

Referring to FIGS. 1 and 2, the LIDAR device 10 includes a light source 100, a scanning unit 200, a synchronization unit 300, a light detection unit 400, and a signal processing unit 500. The LiDAR device 10 may omit some of the various components exemplarily shown in FIGS. 1 and 2 or may additionally include other components.

The light source 100 is a device that emits an optical transmission signal. For example, the light source 100 may emit light in the infrared region, and may use the light in the infrared region to prevent mixing with natural light in the visible region, including sunlight. However, it is not necessarily limited to the infrared region and the light source 100 may emit light in various wavelength regions, and in this case, correction to remove information of mixed natural light may be required.

The light source 100 may transmit an optical transmission signal L1.

The scanning unit 200 receives the emitted light transmission signal L1 and reflects it toward the scan area, receives the light reception signal L2 reflected from the object 20, and sends the light reception signal L2 to the light detection unit. It can be transmitted to (400).

The synchronization unit 300 may synchronize the transmission reflection unit 222 and the reception reflection unit 226 of the scanning unit 200.

The light detection unit 400 may detect the light reception signal L2, which is light reflected (or scattered) by the object 20 located on the scan area, among the light transmission signal L1.

The light detection unit 400 may convert the light reception signal L2 reflected or scattered from the object 20 among the light transmission signal L1 into an electrical signal, for example, a current. The light transmission signal L1 emitted from the light source 100 is irradiated to the object 20 and may be reflected or scattered by the object 20 . Among the light transmission signals L1, the light reflected or scattered by the object 20 is called the light reception signal L2. The optical transmission signal L1 and the optical reception signal L2 may have substantially the same wavelength and different intensities.

According to one embodiment of the present invention, the light detection unit 400 may be a single-element light detector, but is not necessarily limited thereto.

The light detection unit 400 may further include a current-voltage conversion circuit that converts the output current into voltage and an amplifier (not shown) that amplifies the amplitude of the voltage. In addition, the light detection unit 400 may further include a filter that filters an electrical signal of a specific frequency, for example, a high-pass filter.

The optical fiber-connected single-element photodetector has higher sensitivity and response speed than the array-type photodetector used in general LiDAR, and can receive laser signals at high speed, thereby improving the resolution of 3D image information compared to general LiDAR.

The signal processing unit 500 may obtain distance information about the object 20 using the detection result of the light detection unit 400. The signal processing unit 500 may determine the distance from the LIDAR device 10 to the object 20 located on the scan area based on the detected light reception signal L2. The signal processing unit 500 may calculate the distance to the object 20 based on the light emission time of the light source 100 and the light detection time of the light detection unit 400.

Additionally, the signal processing unit 500 may control the operation of each component of the LiDAR device 10, such as the light source 100, the scanning unit 200, the synchronization unit 300, and the light detection unit 400.

LiDAR systems are being developed with the goal of wide scanning angles and high resolution. However, as the scanning angle widens, the optical system configuration of the receiver and the performance of the laser detector improve the performance of the LiDAR system, such as 3D image information measurement distance and spatial resolution. This is degraded.

Existing LIDAR systems use an array detector to receive light at a wide scan angle, or receive reflected light from a target through rotation. However, array detectors have the disadvantage of having a longer response time than single element detectors, which shortens the measurement distance and reduces angular resolution.

Figure 3 is a block diagram illustrating in detail a LIDAR device using an optical interference method according to an embodiment of the present invention.

The LIDAR device 10 uses a reception reflector 226 in the receiver to compensate for the scan angle of the optical transmission signal by the transmission reflector 222. By using the transmission reflector 222 and the reception reflector 226, the optical axis of the optical transmission signal and the optical axis of the optical reception signal can be aligned to be the same. However, if the angles of the transmission reflector 222 and the reception reflector 226 do not match, the LIDAR device 10 cannot receive the optical transmission signal transmitted to the object. Accordingly, the LIDAR device 10 may use an optical synchronization method using a reflection prism, a laser diode, and a synchronization optical detector as a method for synchronizing the transmission reflector 222 and the reception reflector 226. This type of LiDAR optical system has the advantage of being able to scan a wide angular range without deteriorating system performance.

Referring to FIG. 3, the LIDAR device 10 includes a light source 100, a scanning unit 200, a synchronization unit 300, a light detection unit 400, and a signal processing unit 500.

The light source 100 may transmit an optical transmission signal.

The scanning unit 200 receives the light transmission signal and reflects it toward the scan area, receives the light reception signal, controls the angle at which the light reception signal is incident on the light detection unit 400 to be constant, and sends the light reception signal to the light detection unit 400. It can be transmitted to (400).

The scanning unit 200 includes a reflection unit 220 including a transmission reflection unit 222, a transmission/reception reflection unit 224, and a reception reflection unit 226.

The transmission reflector 222 may perform tilt driving in the vertical direction to determine the scan area.

The transmission reflector 222 scans by adjusting the field of view (FOV) in the vertical direction by performing a tilt drive in the vertical direction. The range of the scan angle is determined according to the driving angle, and the range of the scan angle is determined based on the initial control value. Tilt driving can be performed.

The receiving reflector 226 may be synchronized with the transmitting reflector 222 and perform tilt driving at the same angle as the transmitting reflector 222.

The receiving reflector 226 may be synchronized with the transmitting reflector 222 by the synchronization unit 300 to perform tilt driving in the vertical direction according to the driving angle.

The transmitting reflector 222 and the receiving reflector 226 may be implemented as MEMS (Micro Electro Mechanical Systems) mirrors, but are not necessarily limited thereto.

The transmission/reception reflection unit 224 reflects the optical transmission signal reflected and transmitted through the transmission reflection unit 222 toward the object 20, and the reception reflection unit ( 226).

The transmitting/receiving reflector 224 may be implemented as a polygon mirror, but is not necessarily limited thereto.

The scanning unit 200 may further include a transmitting member 210 and a receiving member 230.

The transmission member 210 can convert the optical transmission signal into parallel light.

The receiving member 230 is provided between the receiving reflector 226 and the light detection unit 400, and can focus the light reception signal reflected by the receiving reflector 226 and transmit it to the light detection unit 400.

The synchronization unit 300 includes a synchronization light source 310, a beam splitter 320, a synchronization transmitting/receiving member 330, a reflection prism 340, and an optical synchronization detection unit 350.

The synchronization light source 310 may transmit an optical synchronization signal to synchronize the transmission reflector 222 and the reception reflector 226.

The beam splitter 320 is provided between the synchronization light source 310 and the synchronization transmitting and receiving member 330, and transmits the optical synchronization signal to the synchronizing transmitting and receiving member 330 and transmits the reflected synchronization signal to the optical synchronization detection unit 350. It can be delivered.

The beam splitter 320 may control the reflected synchronization signal received from the synchronization transmitting and receiving member 330 not to be transmitted to the synchronization light source 310.

The synchronous transmitting and receiving member 330 can convert the optical synchronizing signal into parallel light.

The reflection prism 340 transmits the optical synchronization signal to the transmission reflection unit 222 and the reception reflection unit 226, and transmits the reflection synchronization signal reflected from the transmission reflection unit 222 and the reception reflection unit 226 to the synchronization transmission and reception member. It can be delivered to (330).

Reflecting prism 340 includes a first side 342 and a second side 344.

The first surface 342 may transmit the optical synchronization signal to the transmission reflector 222 as a first optical synchronization signal according to a preset first reflectance.

The second surface 344 may transmit the optical synchronization signal to the receiving reflector 226 as a second optical synchronization signal according to a preset second reflectance.

The first reflectance and the second reflectance may be implemented differently.

The first reflection synchronization signal that is reflected and returned from the first optical synchronization signal incident on the transmission reflector 222 and the second reflection synchronization signal that is reflected and returned by the second optical synchronization signal incident on the reception reflector 226 are It can be distinguished by amplitude. Here, the amplitude can be distinguished by the difference in reflectance of the first surface 342 and the second surface 344.

The reflecting prism 340 is spatially divided in half, and the reflectance of the first surface 342 may be higher than that of the second surface 344.

The optical synchronization signal incident on the reflection prism 340 is a first reflection synchronization signal incident and reflected by the transmission reflector 222 and received in a state in which the transmission reflector 222 and the reception reflector 226 are unsynchronized. It may appear larger than the second reflected synchronization signal incident and reflected by the reflector 226.

The optical synchronization detection unit 350 can detect a reflection synchronization signal.

The light detection unit 400 may detect a light reception signal, which is light reflected by the object 20 located on the scan area, among the light transmission signals.

The light detection unit 400 is connected to an optical fiber, and the light reception signal focused by the receiving member 230 is focused on the optical fiber, so that the light reception signal can be transmitted through the optical fiber.

The light detection unit 400 may be configured as an InGaAs-based PIN type, APD type, or SPAD type.

The signal processing unit 500 may obtain distance information about the object 20 using the detection result of the light detection unit 400.

The signal processing unit 500 uses the pulse repetition rate of the light source 100, the driving angle of the transmitting reflector 222, the driving angle of the receiving reflector 226, the rotation angle of the transmitting and receiving reflector 224, or the synchronization unit 300. control, and can calculate distance information about the object 20 through the optical transmission signal and the optical reception signal.

When the transmission reflection unit 222 and the reception reflection unit 226 are unsynchronized, the signal processing unit 500 is configured to reduce the time difference between the first reflection synchronization signal and the second reflection synchronization signal. The driving frequency can be adjusted.

The LiDAR device 10 further includes an optical window 600.

The optical window 600 may have the ability to transmit wavelength bands of the optical transmission signal and the optical reception signal.

The optical window 600 may be provided on the front of the transmitting/receiving reflector 224.

Figure 4 is a diagram showing a LIDAR device using an optical synchronization method according to an embodiment of the present invention.

According to one embodiment of the present invention, the light source 100 may be implemented as a fiber laser. For example, the light source 100 may be implemented to have a laser wavelength in the 1.3 um to 1.7 um band, kW peak power, and MHz laser pulse repetition rate, but is not necessarily limited thereto. . Preferably, the light source 100 may be implemented with a laser wavelength in the 1.5 um band.

The transmission member 210 may be implemented so that the optical transmission signal output from the light source 100 is parallel light. For example, the transmission member 210 may be implemented as an optical lens and transmit the optical transmission signal transmitted from the light source 100 to the transmission reflection unit 222 by converting it into parallel light.

Referring to FIG. 4, the scanning unit 200 includes a reflecting unit 220. Specifically, the reflector 220 includes a transmit reflector 222, a transmit and receive reflector 224, and a receive reflector 226. The scanning unit 200 may omit some of the various components exemplarily shown in FIG. 4 or may additionally include other components.

The transmission reflector 222 scans the vertical field of view (FOV) by driving a tilt in the vertical direction, and the scan angle range can be determined depending on the driving angle.

According to one embodiment of the present invention, the transmission reflector 222 may be implemented as a 2D MEMS mirror, but is not necessarily limited thereto. Micro-electro mechanical systems (MEMS) are implemented to enable rotation in 2D and can secure higher resolution than motor methods.

The transmitting/receiving reflector 224 rotates in the horizontal direction to scan the horizontal field of view (FOV), and the scan angle range is determined according to the number of reflected surfaces.

According to an embodiment of the present invention, the transmitting/receiving reflector 224 may be implemented as a polygon mirror, but is not necessarily limited thereto. A polygon mirror is implemented as a mirror made of regular polygonal prisms with six or more sides, so that each side sufficiently reflects light rays.

The transmission reflector 222 performs a preset vertical rotation, and the transmit/receive reflector 224 performs a preset horizontal rotation of the optical transmission signal to transmit the transmission light to the object. The optical transmission signal may be transmitted along a scan path of a wavy waveform (eg, a sine waveform) within a predetermined scan area. Here, the transmission reflector 222 and the transmit/receive reflector 224 may be synchronized with each other to form a scan path. In other words, the transmission reflector 222 and the transmit/receive reflector 224 can form a scan path of the transmission beam by matching the angles and speeds for horizontal rotation and vertical rotation through synchronization. Here, the scan path of the optical transmission signal changes in size in terms of amplitude, wavelength, period, etc., depending on the angle and speed settings for the horizontal and vertical rotations of the transmission reflector 222 and the transmission and reception reflector 224, respectively. It can be.

The LIDAR device 10 may further include an optical window 600 for transmitting light transmission signals and light reception signals. The optical window 600 may be implemented to have the ability to transmit the wavelength band of the light source 100.

According to one embodiment of the present invention, the optical window 600 may be implemented to further include a frame portion (not shown) that provides a structure for fixation.

The optical window 600 may be provided on the front of the transmitting/receiving reflector 224. Specifically, the optical window 600 is located at a position where the optical transmission signal is reflected by the transmission reflector 222 and transmitted to the transmission/reception reflector 224, and is transmitted toward the object 20 through the transmission/reception reflector 224. It can be implemented at a location where the light reception signal reflected by the object 20 is received by the transmission/reception reflection unit 224.

The receiving reflector 226 is synchronized with the transmitting reflector 222 and performs a tilt operation to tilt at the same angle as the transmitting reflector 222, thereby transmitting the reflected light from the object 20 to the receiving member 230. It can transmit optical reception signals.

The reception reflection unit 226 maintains a constant angle of the light reception signal incident on the light detection unit 400, allowing a single-element photodetector to be applied to the LiDAR device 10.

According to one embodiment of the present invention, the receiving reflector 226 may be implemented as a 2D MEMS mirror, but is not necessarily limited thereto. Micro-electro mechanical systems (MEMS) are implemented to enable rotation in 2D and can secure higher resolution than motor methods.

The receiving member 230 may focus the light reception signal reflected from the object 20 and transmitted through the transmission/reception reflection unit 224 and the reception reflection unit 226 and transmit it to the light detection unit 400.

According to one embodiment of the present invention, the receiving member 230 may be implemented as an optical lens to focus the light reception signal and transmit it to the light detection unit 400, but is not necessarily limited thereto.

The receiving member 230 may be connected to the light detection unit 400 through an optical fiber.

The light reception signal focused in the receiving member 230 may be focused on an optical fiber and transmitted to the light detection unit 400 through the optical fiber.

According to an embodiment of the present invention, the light detection unit 400 may be configured as an InGaAs-based PIN type, APD type, or SPAD type, but is not necessarily limited thereto.

The synchronization unit 300 includes a synchronization light source 310, a beam splitter 320, a synchronization transmitting/receiving member 330, a reflection prism 340, and an optical synchronization detection unit 350. The synchronization unit 300 may omit some of the various components exemplarily shown in FIG. 4 or may additionally include other components.

The synchronization light source 310 is a light source for synchronizing the transmission reflector 222 and the reception reflector 226, and operates in a pulse form with a wavelength in the visible light band to transmit an optical synchronization signal.

According to one embodiment of the present invention, the synchronization light source 31 may be implemented as a laser diode light source and may be connected through an optical fiber.

The beam splitter 320 transmits the optical synchronization signal output from the synchronization light source 310 to the synchronization transmitting and receiving member 330, and transmits the reflected synchronization signal received from the synchronizing transmitting and receiving member 330 to the optical synchronization detector 350. You can.

The beam splitter 320 includes a function to prevent the reflected synchronization signal received by the synchronization transmitting and receiving member 330 from being transmitted to the synchronization light source 310.

The synchronization transmitting and receiving member 330 is connected with an optical fiber, and can transform the optical synchronization signal output from the synchronization light source 310 into parallel light and transmit it to the reflecting prism 340.

The synchronization transmitting and receiving member 330 can transmit the reflected synchronization signal reflected from the transmitting reflector 222, the receiving reflector 226, and the reflecting prism 340 and returned to the optical synchronization detection unit 350.

The reflecting prism 340 includes a first surface 342 that transmits the optical synchronization signal to the transmission reflector 222 and a second surface 344 that transmits the optical synchronization signal to the reception reflector 226. Here, the first surface 342 may represent a right reflective surface, and the second surface 344 may represent a left reflective surface.

According to one embodiment of the present invention, the reflectance of the first surface 342 may be implemented as 80% to 95%, and the reflectance of the second surface 344 may be implemented as 50% to 70%, and must be implemented as 80% to 95%. It is not limited to this. Preferably, the reflectance of the first side 342 is implemented as 90%, and the reflectance of the second side 344 is implemented as 60%.

The reflection prism 340 transmits the optical synchronization signal output from the synchronization light source 310 and transmitted through the synchronization transmission and reception member 330 to the transmission reflection unit 222 and the reception reflection unit 226, and the transmission reflection unit ( 222) and the receiving reflector 226 may receive the reflected synchronization signal and transmit it to the synchronization transmitting and receiving member 330.

According to one embodiment of the present invention, the reflecting prism 340 may transmit a first optical synchronization signal to the transmission reflector 222 and a second optical synchronization signal to the reception reflector 226, and may transmit the first optical synchronization signal to the reception reflector 226. The synchronization signal is reflected from the transmission reflector 222 and transmitted as a first reflection synchronization signal to the synchronization transmitting and receiving member 330, and the second optical synchronization signal is reflected from the receiving reflector 226 as a second reflection synchronization signal. It can be received and transmitted to the synchronous transmitting and receiving member 330.

The optical synchronization detection unit 350 is an optical element for detecting a reflection synchronization signal returned after the optical synchronization signal transmitted from the synchronization light source 310 is reflected from the transmission reflector 222 and the reception reflector 226, and is transmitted through an optical fiber. It is connected.

The signal processing unit 500 can control the pulse repetition rate of the light source 100, the driving angle of the transmitting reflector 222 and the receiving reflector 226, the rotation angle of the transmitting and receiving reflector 224, and the synchronization light source 310. there is.

The signal processing unit 500 performs synchronization control of the transmission reflection unit 222 and the reception reflection unit 226 through the laser pulse received by the optical synchronization detection unit 350.

The signal processing unit 500 may calculate target distance information about three-dimensional coordinates through the light transmission signal transmitted from the light source 100 and the light reception signal reflected from the object 20.

The LiDAR device 10 may further include a display unit 700.

The display unit 700 may display information on the object 20 output through the signal processing unit 500. For example, information about the object 20 displayed on the display unit 700 may be image information of a 3D object, but is not necessarily limited thereto.

According to another embodiment of the present invention, the LIDAR device 10 may further include a driving angle counting unit (not shown), and the display unit 700 may include a lamp (not shown).

The driving angle counting unit (not shown) may calculate the total of the driving angles of each of the transmitting reflector 222 or the receiving reflector 226. For example, the transmitting reflector 222 or the receiving reflector 226 is driven at an angle of 15 degrees during the first drive, at an angle of 12 degrees during the second drive, and at an angle of 22 degrees during the third drive. In one case, the driving angle counting unit (not shown) may calculate that each of the transmitting reflector 222 or the receiving reflector 226 is driven by a total of 49 degrees.

The lamp is a driving member connected to the driving unit to drive the transmitting reflector 222 or the receiving reflector 226 to the user by turning on when the total of the driving angles calculated by the driving angle counting unit is greater than or equal to a predetermined first threshold. It can be notified that the replacement cycle has elapsed.

Since the transmitting reflector 222 or the receiving reflector 226 inevitably performs rotation or tilting operation frequently during the operation of the LiDAR device 10, the transmitting reflector 222 or the receiving reflector 226 is Damage and wear inevitably occur in the members that are fixed to the LiDAR device 10 and the driving members connected to the driving unit, which may cause errors in the distance data of the object 20 output by the LiDAR device 10.

The LiDAR device 10 notifies the user of the replacement cycle of the driving member connected to the driving unit through the driving angle counting unit and the lamp, allowing the user to replace the driving member connected to the driving unit, so that the LiDAR device 10 outputs Errors in distance data for the target object 20 can be prevented.

According to another embodiment of the present invention, the signal processing unit 500 calculates the length of the optical path between the light source 100 and the optical window 600 inside the LiDAR device 10 by using the light source 100 and the optical window 600. The average value of the first optical path, which is the distance between the first side of the optical window 600, and the second optical path, which is the distance between the light source 100 and the second side diagonally symmetrical with the first side of the optical window 600. It may be to seek . Here, when the optical window is implemented as a square, the first side may represent the upper left corner, and the second side may represent the lower right corner, but are not necessarily limited thereto. The signal processor 500 calculates the length of the optical path between the light source 100 inside the LiDAR device and the optical window 600 by using at least two light reflection mirrors to calculate the length of the optical path inside the LiDAR system (light source inside the LiDAR system) The length of the optical path between 100) and the optical window 600 may be multiplied by a weight predetermined by the user (for example, 1.002 to 1.005). For example, the signal processing unit 500 calculates the length of the optical path between the light source 100 and the optical window 600 inside the lidar device from the average value of the first optical path and the second optical path described above. It may be calculating a value multiplied by a predetermined weight. The predetermined weight may vary depending on the material of the optical window 600 and the environment (eg, temperature and humidity) in which the LiDAR device 10 is operated.

The LIDAR device 10 may additionally include a received light quantity confirmation unit (not shown). Here, the received light quantity confirmation unit measures the received light quantity on the receiving side. Here, the received light quantity confirmation unit may be implemented as a module that measures the amount of received light reflected from the object 20 in conjunction with the optical window 600, the reception reflection unit 226, etc., but is not necessarily limited thereto, and the light detection unit 400 ) or may be implemented in the form of hardware included in the light detection unit 400 or a program installed in the light detector.

The signal processing unit 500 may compare the measured received light amount with a preset reference light amount to adjust the transmitted light amount, the rotation angle of the transmission reflector 222, the rotation speed of the transmission reflector 222, etc.

Specifically, when the measured received light amount is less than the reference light amount, the signal processor 500 may adjust at least one of the transmitted light amount, the rotation angle of the transmission reflector 222, and the rotation speed of the transmission reflector 222.

The signal processing unit 500 may adjust the received light amount to a reference light amount or more using one of the first adjustment value, the second adjustment value, and the third adjustment value.

The signal processing unit 500 may adjust the transmission light quantity by applying the first adjustment value to the existing transmission light quantity, and then, if the measured received light quantity is greater than or equal to the reference light quantity, update the transmission light quantity to the adjusted transmission light quantity. In addition, the signal processing unit 500 adjusts the rotation angle of the transmission reflector 222 by applying the second adjustment value to the rotation angle of the existing transmission reflector 222, and if the measured received light amount is greater than or equal to the reference light amount, the signal processor 500 applies the second adjustment value to the rotation angle of the existing transmission reflector 222. The rotation angle of the unit 222 can be updated to the adjusted rotation angle. In addition, the signal processor 500 adjusts the rotation speed of the transmission reflector 222 by applying the third adjustment value to the rotation speed of the existing transmission reflector, and if the measured received light amount is greater than or equal to the reference light amount, the transmission reflector 222 The rotation speed can be updated to the adjusted rotation speed.

Meanwhile, even when one of the first adjustment value, the second adjustment value, and the third adjustment value is used, the signal processing unit 500 uses the first adjustment value, the second adjustment value, and the third adjustment value when the measured received light amount is less than the reference light amount. By applying each adjustment value sequentially, the received light amount can be adjusted to exceed the standard light amount.

For example, the signal processor 500 adjusts the transmission light amount by first applying the first adjustment value, and sequentially applies the second adjustment value and the third adjustment value, respectively, to adjust the rotation angle and the rotation angle of the transmission reflector 222. The rotation speed of the transmitting reflector can be adjusted. Here, the order of applying the adjustment values may change depending on the settings.

Meanwhile, the signal processor 500 adjusts the condition using a combination of some adjustment values if the measured received light amount is less than the reference light amount even when one or all of the first adjustment values, second adjustment values, and third adjustment values are applied sequentially. Thus, the received light amount can be adjusted to exceed the standard light amount.

Specifically, the signal processing unit 500 may adjust the received light amount to more than the reference light amount by applying at least one adjustment value among the first adjustment value, the second adjustment value, and the third adjustment value.

For example, the signal processor 500 may adjust the amount of transmission light and the rotation angle of the transmission reflector 222 by combining the first adjustment value and the second adjustment value. Here, the signal processing unit 500 may reflect and combine the respective ratios of the first adjustment value and the second adjustment value differently. That is, the signal processing unit 500 can adjust each of the transmission light quantity and the rotation angle of the transmission reflection unit 222 by combining the first adjustment value and the second adjustment value with different weights.

The signal processing unit 500 can transform and combine the first adjustment value, the second adjustment value, and the third adjustment value into various conditions that can be combined, and then apply them to adjust the received light amount to a reference light amount or more.

Figure 5 is a diagram showing a reflecting prism of a lidar device using an optical synchronization method according to an embodiment of the present invention.

Referring to FIG. 5, the reflective prism 340 may include a first surface 342 and a second surface 344 for transmitting the optical synchronization signal to the transmission reflection unit 222 and the reception reflection unit 226. there is.

According to one embodiment of the present invention, the reflection prism 340 is formed in a triangular shape, and when an optical synchronization signal flows into one vertex, the transmission reflection unit ( 222) and the receiving reflector 226. In addition, the reflected synchronization signal reflected from the transmitting reflector 222 and the receiving reflector 226 is reflected through the first surface 342 and the second surface 344 and transmitted to the synchronization transmitting and receiving member 330 through one vertex. It can be delivered.

According to one embodiment of the present invention, the reflectance of the first surface 342 may be implemented as 80% to 95%, and the reflectance of the second surface 344 may be implemented as 50% to 70%, and must be implemented as 80% to 95%. It is not limited to this. Preferably, the reflectance of the first side 342 is implemented as 90%, and the reflectance of the second side 344 is implemented as 60%.

According to an embodiment of the present invention, the first reflectance may be implemented to be higher than the second reflectance, but is not necessarily limited to this, and different reflectances may be used to distinguish the first reflection synchronization signal and the second reflection synchronization signal. It can be implemented to form.

Figure 6 is a diagram showing a method of synchronizing the transmitting reflector and the receiving reflector of the lidar device using an optical synchronization method according to an embodiment of the present invention.

The LIDAR device 10 uses an optical synchronization method to synchronize the transmitting reflector 222 and the receiving reflector 226.

The synchronization unit 300 includes a synchronization light source 310, a beam splitter 320, a synchronization transmitting/receiving member 330, a reflection prism 340, and an optical synchronization detection unit 350.

The synchronization light source 310 may generate an optical synchronization signal.

The optical synchronization detector 350 may receive an optical synchronization signal generated from the synchronization light source 310.

The transmitting reflector 222 and the receiving reflector 226 may perform a tilt drive that tilts in the vertical direction.

The optical synchronization signal from the synchronization light source 310 may be reflected perpendicularly to the transmission reflector 222 and the reception reflector 226 when the inclination of the transmission reflector 222 and the reception reflector 226 is 0 degrees. .

The synchronization unit 300 may be implemented so that the optical paths of the optical synchronization signal and the reflection synchronization signal incident and reflected by the transmission reflector 222 and the reception reflector 226 are the same. Here, the incident beam is an optical synchronization signal, and the reflected beam is a reflection synchronization signal.

When the optical paths of the incident beam and the reflected beam of the transmitting reflector 222 and the receiving reflector 226 match, the reflected reflected synchronization signal will be transmitted to the optical synchronization detection unit 350 through the synchronization transmitting and receiving member 330. You can. That is, when the transmission reflector 222 and the reception reflector 226 are synchronized, when the transmission reflector 222 and the reception reflector 226 are driven once, the optical synchronization detection unit 350 generates an optical signal twice. In addition to receiving, the driving frequencies of the transmitting reflector 222 and the receiving reflector 226 can be measured.

A first reflection synchronization signal in which the first optical synchronization signal incident on the transmission reflector 222 is reflected and returned, and a second reflection synchronization signal in which the second optical synchronization signal incident on the reception reflection unit 226 is reflected and returned. can be distinguished by amplitude.

The amplitude of the first reflection synchronization signal and the amplitude of the second reflection synchronization signal can be implemented by varying the reflectivity of the reflection prism 340.

The optical synchronization signal incident on the reflecting prism 340 is spatially divided in half, and the reflectance of the first surface 342 is implemented to be higher than the reflectivity of the second surface 344, so that the transmitting reflector 222 and the receiving In an unsynchronized state of the reflector 226, the first reflected synchronization signal from the transmission reflector 222 may appear larger than the second reflected synchronization signal from the receive reflector 226.

Accordingly, the LIDAR device 10 performs the following procedure to synchronize the transmitting reflector 222 and the receiving reflector 226.

Referring to (b) of FIG. 6, when the transmission reflector 222 and the receive reflector 226 are unsynchronized, a time difference may occur between the first reflection synchronization signal and the second reflection synchronization signal.

The signal processor 500 can reduce the time difference by adjusting the driving frequencies of the transmit reflector 222 and the receive reflector 226.

The signal processing unit 500 is in a synchronization state in which the first reflection synchronization signal of the transmission reflection unit 222 and the second reflection synchronization signal of the reception reflection unit 226 appear as an overlapped optical signal, as shown in (a) of FIG. 6. You can control it.

7 to 9 are flowcharts showing a method of operating a LIDAR device using an optical synchronization method according to an embodiment of the present invention. The operation method of the LiDAR device is performed by the LiDAR device, and descriptions that overlap with the LiDAR device in the above drawings will be omitted.

Figure 7 is a flowchart showing a method of operating a LiDAR device according to an embodiment of the present invention.

The method of operating a LiDAR device is a method of operating a LiDAR device using a LiDAR device,

The synchronization light source transmits an optical synchronization signal (S710), receiving the first reflection synchronization signal reflected from the transmission reflector by the optical synchronization signal and the second reflection synchronization signal reflected from the reception reflector and the transmission reflector and Comparing the driving frequency of the receiving reflector and synchronizing the transmitting reflector and the receiving reflector (S720). When synchronized, rotating the transmitting and receiving reflector, transmitting the optical transmission signal toward the object through the light source, and rotating the receiving reflector. It includes a step of receiving a light reception signal through a detection unit and detecting the light reception signal through a detection unit (S730), and a step of the signal processing unit obtaining distance information about the object using the detection result of the light detection unit (S740).

The operating method of the LIDAR device is described in more detail with reference to FIGS. 8 and 9.

Figures 8 and 9 are flowcharts illustrating in detail a method of operating a LiDAR device through synchronization of a transmitting reflector and a receiving reflector according to an embodiment of the present invention.

Referring to FIG. 8, the operating method of the LIDAR device includes the steps of transmitting an initial control value (S810), the signal processor generating a driving signal of the transmission reflector (S820), and the transmission reflector performing a tilting operation (S820). S822), the signal processor receives the angle of the transmission reflector (S830), the step of checking whether the angle of the transmission reflector is 0 degrees (S832), the signal processor generates a trigger signal (S840), the synchronization light source triggers A step of receiving a signal (S850), a step of the synchronization light source generating a laser pulse (S860), a step of the optical synchronization detection unit receiving the reflection synchronization signal of the transmission reflector (S870), and the signal processing unit measuring the driving frequency of the transmission reflector. It includes a step (S880) and a step (S890) of comparing the driving signal and the driving frequency.

The signal processing unit receives the angle of the transmission reflector (S830) and checks whether the angle of the transmission reflector is 0 degrees (S832). If the angle is 0 degrees, step S832 is performed, and if the angle is not 0 degrees, step S820 is performed. It can be done.

The step of comparing the driving signal and the driving frequency (S890) checks whether the driving frequency according to the driving signal matches, and if not, the step of adjusting the driving signal of the transmission reflector (S892) is performed.

Referring to FIG. 9, the method of operating the LIDAR device includes a signal processing unit generating a driving signal of the receiving reflector (S910), a receiving reflecting unit performing a tilting operation (S912), and an optical synchronization detection unit transmitting/ Receiving the reflection synchronization signal of the receiving reflector (S920), comparing the driving frequency of the transmitting/receiving reflector (S930), operating the light source (S940), rotating the transmitting and receiving reflector (S950), object It includes receiving data (S960) and displaying object data (S970).

Step S910 can be performed when the driving frequency according to the driving signal matches in step S890.

In the step S930 of comparing the driving frequencies of the transmitting/receiving reflectors, if the driving frequencies of the transmitting/receiving reflectors match, step S940 is performed. If the driving frequencies of the transmitting/receiving reflectors do not match, the driving signal of the receiving reflectors is performed. Perform the adjustment step (S932).

In FIGS. 7 to 9, each process is shown as being sequentially executed, but this is merely an illustrative explanation, and those skilled in the art may refer to FIGS. 7 to 9 without departing from the essential characteristics of the embodiments of the present invention. It can be applied through various modifications and modifications, such as executing by changing the described order, executing one or more processes in parallel, or adding other processes.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications, changes, and substitutions can be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the attached drawings are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments and the attached drawings. . The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

10: LIDAR device
100: light source
200: scanning unit
210: Transmitting member
220: reflection part
222: Transmission reflection unit
224: Transmission/reception reflector
226: Receiving reflection unit
230: Absence of reception
300: synchronization unit
400: Light detection unit
500: signal processing unit
600: optical window
700: Display unit
20: object

Claims (13)

A light source that transmits an optical transmission signal;
a light detection unit that detects a light reception signal, which is light reflected by an object located on the scan area, among the light transmission signals;
Receive the light transmission signal and reflect it toward the scan area, receive the light reception signal and control the angle at which the light reception signal is incident on the light detection unit to be constant, and direct the light reception signal toward the light detection unit. a scanning unit that transmits;
a synchronization unit that synchronizes the transmission reflector that determines the scan area and the reception reflector that controls the incident angle to be constant through optical synchronization; and
A signal processing unit that obtains distance information about the object using the detection result of the light detection unit,
The scanning unit includes a transmission reflection unit that determines the scan area by performing a tilt drive in a vertical direction; a receiving reflector that is synchronized with the transmit reflector and performs tilt driving at the same angle as the transmit reflector; and a transmitting/receiving reflection unit that reflects the optical transmission signal reflected and transmitted through the transmission reflection unit toward the object, and reflects the optical reception signal reflected and transmitted through the object to the reception reflection unit,
The synchronization unit includes a synchronization light source that transmits an optical synchronization signal for synchronizing the transmission reflector and the reception reflector; a synchronous transmitting and receiving member that converts the optical synchronizing signal into parallel light; a reflecting prism that transmits the optical synchronization signal to the transmission reflector and the reception reflector and transmits the reflection synchronization signal reflected from the transmission reflector and the reception reflector to the synchronization transmission and reception member; and an optical synchronization detection unit that detects the reflection synchronization signal,
The reflective prism includes: a first surface that transmits the optical synchronous signal to the transmission reflector as a first optical synchronous signal according to a preset first reflectivity; And a second surface that transmits the optical synchronization signal to the receiving reflector as a second optical synchronization signal according to a preset second reflectivity,
A LiDAR device, characterized in that the first reflectance and the second reflectance are implemented differently. delete According to paragraph 1,
The transmit reflector,
By performing a tilt drive in the vertical direction, the field of view (FOV) in the vertical direction is adjusted and scanned, and the range of the scan angle is determined according to the drive angle according to the tilt drive, and based on the initial control value. Tilt drive is performed,
The LiDAR device is characterized in that the receiving reflector is synchronized with the transmitting reflector by the synchronization unit and tilt drive is performed in the vertical direction according to the driving angle. delete According to paragraph 1,
The synchronization unit,
It is provided between the synchronization light source and the synchronization transmitting and receiving member, and further includes a beam splitter that transmits the optical synchronizing signal to the synchronizing transmitting and receiving member and transmits the reflected synchronizing signal to the optical synchronization detection unit,
The beam splitter is a lidar device characterized in that it controls the reflected synchronization signal received from the synchronization transmitting and receiving member so that it is not transmitted to the synchronization light source. delete According to paragraph 1,
The first reflection synchronization signal, which is reflected and returned from the first optical synchronization signal incident on the transmission reflector, and the second reflection synchronization signal, which is the reflection and return of the second optical synchronization signal incident on the reception reflector, can be distinguished by amplitude. And
A LiDAR device, characterized in that the amplitude is distinguished by a difference in reflectance of the first surface and the second surface. According to paragraph 1,
The reflecting prism is,
It is spatially divided in half, and the reflectance of the first side is implemented to be higher than the reflectance of the second side,
The optical synchronization signal incident on the reflection prism is a first reflection synchronization signal incident on and reflected by the transmission reflector and the second reflection synchronization signal incident on and reflected by the reception reflector in a state in which the transmission reflector and the reception reflector are unsynchronized. 2 Lidar device characterized in that it appears larger than the reflected synchronization signal. According to clause 8,
The signal processing unit,
When the transmission reflector and the reception reflector are unsynchronized, adjusting the driving frequency of the transmission reflector and the reception reflector to reduce the time difference occurring between the first reflection synchronization signal and the second reflection synchronization signal. Featured LiDAR device. According to paragraph 1,
The scanning unit,
a transmission member that converts the optical transmission signal into parallel light; and
The lidar device further includes a receiving member provided between the receiving reflection unit and the light detection unit, and focusing the light reception signal reflected by the receiving reflection unit and transmitting the received signal to the light detection unit. According to clause 10,
The light detection unit,
It is connected to an optical fiber, and the optical reception signal focused in the receiving member is focused on the optical fiber, and the optical reception signal is transmitted through the optical fiber,
The light detection unit is a lidar device characterized in that it is composed of an InGaAs-based PIN type, APD type, or SPAD type. According to paragraph 1,
The signal processing unit,
Controls the pulse repetition rate of the light source, the driving angle of the transmission reflector, the driving angle of the reception reflector, the rotation angle of the transmission and reception reflector, or the synchronization unit, and provides distance information to the object through the optical transmission signal and the optical reception signal. A lidar device characterized in that it calculates . In the method of operating a LiDAR device by aligning the optical axis of the optical transmission signal and the optical axis of the optical reception signal and then driving the LiDAR device,
A synchronization light source transmitting an optical synchronization signal;
The first reflection synchronization signal reflected from the transmission reflector by the optical synchronization signal and the second reflection synchronization signal reflected from the reception reflector are received to compare the driving frequencies of the transmission reflector and the reception reflector, and the transmission reflection synchronizing the receiving reflector and the receiving reflector;
After synchronizing the transmission reflector and the reception reflector, the transmission and reception reflectors are rotated and driven, an optical transmission signal is transmitted toward the object through a light source, and an optical reception signal is received through the reception reflection unit, and the light is transmitted through the light detection unit. Detecting a received signal; and
A signal processing unit comprising the step of obtaining distance information about the object using the detection result of the light detection unit, which detects an optical reception signal, which is light reflected by an object located on the scan area, among the optical transmission signals. This is how the device operates.

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