JP2012058079A - Laser radar system and mobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized laser radar system through simple processing.SOLUTION: During a scan mode, scanning is performed over a wide deflection range by a light deflecting element 21 using an electro-optical crystal. Reflection light from a target is received by a light receiving element 31 and the target is captured. The time from light emission to light reception is measured by a time measuring section 220 and on the basis of the time, a distance to the target or a differential speed is calculated by a distance/differential speed calculation section 231. During a tracking mode switched from the scan mode, on the other hand, deflection scanning is performed at a deflection angle smaller than that during the scan mode, by the light deflecting element 21. A plurality of reflection light beams from the target are received by the light receiving element, and the target is tracked.

Description

  The present invention relates to a laser radar system and a moving body.

  The laser radar system detects the position of an object by emitting laser light of a pulse wave or modulated wave to the object and detecting the reflected light of the laser from the object, and irradiates the object with the pulsed laser light. By measuring the time to receive the reflected light from the object, or by detecting the phase difference between the modulated laser beam and the reflected light, the distance to the object is calculated, and the laser radar system and the object If the object is a moving object, it is a system for calculating the differential speed between the laser radar system and the moving object. In such a laser radar system, an optical scanning device such as a motor actuator and a polygon mirror is used to widen the detection range.

  In a vehicle laser radar system in which this laser radar system is mounted on a vehicle that is one of moving bodies, there are two modes: a scan mode and a tracking mode. The scan mode is a mode in which a laser beam is scanned over a wide area to search for the presence of a forward vehicle in the forward detection range. On the other hand, the tracking mode is a mode in which the moving forward vehicle is continuously irradiated with laser light for a predetermined time and the forward vehicle is tracked based on the reflected light. In order to increase the S / N ratio in this tracking mode, the moving vehicle ahead is continuously irradiated with laser light.

  As this vehicle laser radar system, the one described in Patent Document 1 is known. The vehicular laser radar system described in Patent Document 1 has both a scan mode and a tracking mode, and further switches between the scan mode and the tracking mode in order to quickly capture an interruption ahead of the vehicle in the tracking mode. It has a processing means. Then, the object is captured by detecting the reflected light of the pulsed laser light emitted from the laser head by the light receiving unit.

  If the front vehicle, which is the object being captured, moves greatly in either the left or right direction relative to the subject vehicle due to a lane change or the like, the left and right sides are determined only from the information on the amount of reflected light from one laser beam in the tracking mode. It was difficult to identify which direction it moved. There are two methods as countermeasures, and one is a method of switching from the tracking mode to the scan mode as in Patent Document 1 described above. In other words, by switching from tracking mode, which is tracking by irradiating one laser beam to the front vehicle, scanning the wide detection range again, and capturing the front vehicle again, the left and right movement direction of the front vehicle is changed. Detect. After that, it switches to the tracking mode again and tracks the vehicle ahead. However, in the case of using the method of switching the mode of Patent Document 1 described above, the tracking mode is switched to the scanning mode and the object search is performed again, so the distance data of the front vehicle and the own vehicle change, and the tracking mode is switched again. Tracking is not possible immediately after. For this reason, it is necessary to calculate the distance to the object and the differential speed again, and there is a problem that the processing becomes complicated. Another method of the above countermeasure is the combined use with an in-vehicle camera. As an alternative to the scan mode, this is a combined use method with an in-vehicle camera that detects the front in a wide range using a camera and recognizes the front vehicle by image processing while tracking the front vehicle in the tracking mode. However, this method has a problem that the entire system becomes large-scale, and needs for a simple and small laser radar system cannot be satisfied.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a small-sized laser radar system and a moving body equipped with the laser radar system by simple processing.

In order to achieve the above object, the invention according to claim 1 is directed to a light emitting means for irradiating a moving object with laser light, and a laser beam in a scanning range by changing a deflection angle of the laser light emitted by the light emitting means. Light deflecting means for scanning light, light receiving means for receiving laser light reflected from the object, the light emitting means and driving means for driving the light receiving means, and the laser light irradiated by the light emitting means as the light deflecting means A scanning mode in which reflected light from the object is received by the light receiving means and the object is captured by the light receiving means, and a tracking mode in which the light reflected from the object is received by the light receiving means and the object is tracked. A laser radar module having a switching means for switching between, a light emission signal supply section for supplying a light emission signal to the light emission means, and the light emission means for irradiation. A signal processing unit including a distance difference speed calculation unit that calculates a distance to the object and a difference speed based on the laser beam and the laser beam irradiated to the object and reflected from the object; In the laser radar system for detecting the presence / absence of an object, the distance to the object, and the differential speed, in the tracking mode, the light deflecting means is controlled by the light deflecting means from the light emitting means at a deflection angle smaller than the deflection angle in the scan mode. The irradiated laser beam is deflected and scanned, and a plurality of reflected lights from the object are received by the light receiving means to track the object.
According to a second aspect of the present invention, in the laser radar system according to the first aspect of the present invention, based on signal information of a laser beam reflected from an object of the laser beam by deflection scanning at a small deflection angle by the optical deflection unit. A deflection angle correction unit that corrects a deflection angle of the light deflection unit is provided.
Further, the invention of claim 3 is the laser radar system according to claim 1 or 2, wherein the light deflecting means has a light deflecting element using an electro-optic crystal in which a prism-type domain-inverted region is formed. It is a characteristic.
According to a fourth aspect of the present invention, in the laser radar system according to the third aspect, the electro-optical crystal is any one of lithium niobate, magnesium oxide-added lithium niobate, and lithium tantalate. is there.
Further, the invention of claim 5 is the laser radar system according to any one of claims 1 to 3, further comprising a deflecting means for deflecting the laser beam perpendicularly to the light deflecting means. Is.
A sixth aspect of the present invention is a moving body including the laser radar system according to any one of the first to fifth aspects.

  In the present invention, a laser beam is scanned on the object of the moving body in the tracking mode at a minute deflection angle to receive a plurality of reflected lights. Each received light intensity increases or decreases as the object moves left and right. The direction of movement of the relative position of the object to the left and right can be detected from the increase / decrease of each received light signal. As a result, the tracking mode is switched to the scan mode as before, the tracking mode is switched to the tracking mode, and the tracking mode is performed without performing the complicated process of calculating the distance to the moving body and the differential speed. The object can be tracked with high accuracy by the processing as it is.

  As described above, according to the present invention, it is possible to provide a small laser radar system and a moving body equipped with the laser radar system by simple processing.

It is a figure which shows the structure of the light emission part in the laser radar system of embodiment, a light deflection | deviation part, and a light-receiving part. It is a schematic perspective view which shows the structure of an optical deflection | deviation element. It is a schematic perspective view which shows the structure of the electro-optic prism in an optical waveguide layer. It is a schematic perspective view which shows the structure of an electro-optic crystal. It is a characteristic view showing the result of measuring the deflection response of the laser beam when a step voltage is applied to the optical deflection element of the electro-optic crystal. It is a figure which shows the relationship between the polarization angle of the light polarizing element of this embodiment, and an applied voltage. It is a schematic block diagram which shows the structure of the laser radar system of this embodiment. It is a wave form diagram which shows the waveform of the start pulse and stop pulse from a light emission circuit. It is the schematic which shows the mode of the laser beam scanning at the time of the scan mode in the vehicle carrying a laser radar system. It is a flowchart which shows the mode switching operation | movement in the laser radar system of this embodiment. It is a characteristic view which shows the voltage applied to the optical deflection element in the scan mode and the received light signal intensity. It is the schematic which shows the mode of the reflector detection of the front vehicle at the time of the tracking mode in the vehicle carrying a laser radar system. It is a figure which shows the time-dependent change of the applied voltage of the light polarizing element of 3 directions. It is the schematic which shows the mode of the detection in tracking mode when a front vehicle moves to the right direction with respect to the own vehicle. FIG. 6 is a characteristic diagram showing changes in received light intensity from three directions when a forward vehicle moves rightward with respect to the host vehicle.

Hereinafter, embodiments of a laser radar system to which the present invention is applied will be described.
FIG. 1 is a diagram illustrating a configuration of a light emitting unit, a light deflecting unit, and a light receiving unit in the laser radar system of the embodiment. In the figure, the same reference numerals as those in FIG. 1 denote the same components. A small and inexpensive laser diode is used for the light emitting element 11 as the light source of the light emitting unit 10 shown in FIG. In addition, a collimating lens 13 is placed immediately before the light emitting element 11 to collimate the laser light. The light deflecting unit 20 condenses the laser light from the light emitting unit 10 by a condensing lens 23 such as a cylindrical lens, and deflects it through an optical deflecting element 24 using an electro-optic crystal in which an electro-optic prism is formed. In order to enlarge the angle of view of the laser light deflected by the light deflection element 24, a collimating lens 25 of a plano-concave lens and a field angle enlargement lens 26 of a plano-convex lens are arranged immediately after the light deflection element 24. On the other hand, the light receiving unit 30 shown in FIG. 5B is provided with a light receiving element 31 of a photodiode, and a light blocking filter 33 and a condensing lens 34 for blocking external light are installed immediately before the light receiving element 31. Since the wavelength of the laser beam is not visible to the human eye and inexpensive Si is good for the photodiode, a near infrared ray of 850 [nm] to 1000 [nm] is used.

FIG. 2 is a schematic perspective view showing the configuration of the optical deflection element. The optical deflection element 24 shown in the figure is configured by laminating an optical waveguide layer 24-1, an upper electrode 24-2, and a lower electrode 24-3. One electro-optic material used for the optical waveguide layer 24-1 is magnesium oxide-added lithium niobate. This material is characterized by a large electro-optic constant and a high resistance to optical damage. Lithium niobate or lithium tantalate is preferable if the wavelength of the light source used is 900 [nm] or more and the light energy density is 10 [W / cm ² ] or less. For the optical deflection element 24 of the laser radar system 1 of this embodiment, a magnesium oxide-added lithium niobate Z plate was used. The upper electrode 24-2 and the lower electrode 24-3 are formed by sputtering so as to sandwich the Z plate, and the laser beam is propagated in the X direction or the Y direction.

  Furthermore, as shown in FIG. 3, at least one electro-optic prism 24-4 is formed in the optical waveguide layer 24-1. There are two methods for forming the electro-optic prism 24-4. The method includes forming a prism-type electrode or a prism-type domain-inverted region. In the latter case, the deflection angle can be doubled with the same element applied voltage. Therefore, in this embodiment, an element in which a prism-type domain-inverted region is formed is used.

  Here, assuming that the refractive index of the optical deflection element 24 is n and the change in refractive index caused by the electro-optic effect is Δn, when an AC voltage is applied to the optical waveguide layer 24-1 of the optical deflection element 24, the polarization inversion is performed. It is known that the refractive index change has an opposite sign, such that the region is n + Δn to n−Δn, and the non-polarized region is n−Δn to n + Δn. Therefore, a refractive index difference of 2Δn occurs at the boundary of the prism polarization inversion region. Due to this refractive index difference, the laser light is refracted in each prism polarization inversion region, and as a result, the outgoing light from the optical waveguide layer is deflected. As shown in FIG. 2, the optical deflection element 24 includes an optical waveguide layer 24-1, an upper electrode 24-2, and a lower electrode 24-3.

  Also, as shown in FIG. 4, the optical waveguide layer 24-1 can be driven at a lower voltage than the bulk type by having a waveguide structure. As a result, the power consumption of the optical deflector using the optical deflection element 24 having the optical deflection function can be reduced. The waveguide type optical deflection element 24 is composed of an optical waveguide layer 24-1 including an upper clad layer 24-1a, a core layer 24-1b, and a lower clad layer 24-1c, an upper electrode 24-2, a lower electrode 24-3, and an adhesive. It is composed of a layer 24-5, a support substrate 24-6, and a lower extraction electrode 24-7. Conventionally, the used optical deflecting elements include polygon mirrors and drive actuators. On the other hand, the optical deflection element shown in FIGS. 2 to 4 has a small deflection angle, can be driven with low power, and does not require a driving unit such as a motor, and thus is not easily affected by disturbances such as vibration. Since the on-vehicle laser radar performs optical scanning in a dynamic situation, for example, when a car operates during driving, an optical deflecting element using an electro-optic crystal that does not require a driving unit is suitable. Further, since the laser radar module can be operated only with the electro-optic crystal, the laser radar module can be manufactured in a small size.

  The optical deflection element of the electro-optic crystal can perform discontinuous optical scanning (random access). FIG. 5 shows the result of measuring the deflection response of the laser beam when a step voltage is applied to the optical deflection element of the electro-optic crystal. As shown in the figure, since the deflection response takes about 3.3 [μs], random access is possible for optical scanning up to 100 kHz. Furthermore, if a DC voltage is applied, the light can be changed in a certain direction. Therefore, unnecessary optical scanning can be eliminated in the tracking mode, and the S / N ratio of the received light signal can be improved.

  FIG. 6 is a diagram showing the relationship between the polarization angle of the light polarizing element of this embodiment and the applied voltage. Since the primary electro-optic effect is used, the deflection angle and the applied voltage have a linear relationship. In this embodiment, a laser radar system with improved tracking accuracy in the tracking mode is manufactured by using the characteristics of the optical deflection element of the electro-optic crystal.

  FIG. 7 is a schematic configuration diagram showing the configuration of the laser radar system of this embodiment. The laser radar system 1 according to the embodiment shown in the figure includes a laser radar module 100 and a signal processing unit 200. The laser radar module 100 includes a light emitting unit 10, a light deflecting unit 20, and a light receiving unit 30. Further, the light emitting unit 10 includes a light emitting element 11 and a light emitting circuit 12 that drives the light emitting element 11 in accordance with a start pulse from a pulse generating unit described later. The light deflection unit 20 includes a light deflection element 21 and a light deflection circuit 22. Further, the light receiving unit 30 includes a light receiving element 31 and a light emitting circuit 32 that outputs a stop pulse from a signal received by the light receiving element 31.

  On the other hand, the signal processing unit 200 outputs a start pulse to the light emitting circuit 12, and measures time by measuring the time difference between the start pulse supplied from the pulse generator 210 and the stop pulse supplied from the light receiving circuit 32. Unit 220, distance / difference speed calculation unit 231 for calculating inter-vehicle distance / speed difference based on the time difference, scan mode / tracking mode switching determination unit 232 for determining switching between scan mode / tracking mode, and distance / differential speed calculation unit The main control unit 230 includes an alarm determination unit 233 that determines whether to notify the danger according to the inter-vehicle distance or the differential speed calculated by the H.231. When the laser radar system 1 determines that the alarm is to be issued by the alarm determination unit 233, the alarm means 300 for notifying the passenger including the driver by an alarm and the distance between the vehicle calculated by the distance / differential speed calculation unit 231 A display means 400 for displaying distance and differential speed, and a power source 500 for supplying driving power to the light emitting circuit 12 and the pulse generator 210 are provided. In the present embodiment, the laser light emitted from the light emitting unit 10 is a pulse wave, but may be a modulated wave. In the case of a modulated wave, the inter-vehicle distance can be calculated by detecting the phase difference between the emitted laser beam and the reflected laser beam.

  According to the laser radar system of the embodiment having such a configuration, when the power supply unit 500 is turned ON / OFF, the pulse generation unit 210 generates a start pulse in the light emitting circuit 12, and the pulse laser is emitted from the laser diode emitting element 11. Exit. At the same time, the time measuring unit 220 starts measuring time with a start pulse from the pulse generating unit 210. When the start pulse is generated, a voltage signal in the scan mode is applied from the optical deflection circuit 22 to the optical deflection element 21. The pulse laser emitted from the light emitting element 11 is applied to the front vehicle, which is the object, and is reflected from the front vehicle. The reflected light is received by the light receiving element 31 and the signal is amplified by the light receiving circuit 32. The signal is output to the time measuring unit 220 as a stop pulse.

Then, as shown in FIG. 8, the time measuring unit 220 measures the time interval Δt _n between the start pulse from the pulse generating unit 210 and the stop pulse from the light receiving circuit 32, and sends it to the distance / differential velocity measuring unit 231 as time data. Output. The distance / differential speed measuring unit 231 calculates the distance from the preceding vehicle from the time data. Further, the time interval between the start pulse from the pulse generator 210 and the stop pulse from the light receiving circuit 32 is measured a plurality of times, and the change amount Δt _{n + 1} −Δt _n of the time interval is obtained to calculate the differential speed with the preceding vehicle. The distance / differential speed measuring unit 231 notifies the driver and passengers of the distance / differential speed information by the speed display means 400. When a collision is predicted by the alarm determination unit 233 from the obtained distance / differential speed information, the alarm unit 300 that issues an alarm to the driver and passengers is activated. Thereby, it becomes possible to apply to a driving support device or the like.

Next, the scan mode and tracking mode in the laser radar system of this embodiment will be outlined.
FIG. 9 is a schematic view showing a state of laser beam scanning in the scan mode. In the scan mode, a laser beam is scanned from the own vehicle A over a wide range to search for the presence of the forward vehicle B. A linear voltage signal as shown in FIG. 9 is applied to the optical deflection element, and the laser light is line-scanned. In the laser radar system of the present embodiment, λ870 [nm], a repetition frequency of 100 [kHz], a pulse width of 30 [ns], and an average power of 100 [mW] are used. The applied voltage of the optical deflection element is ± 150 [V], the scanning frequency is 30 [Hz], the scanning angle is 30 °, and the angular resolution is 0.3 °. When scanning from the initial scanning angle θs to the scanning end angle θe, the scan mode / tracking mode switching determination unit 232 of the main control unit 230 in FIG. 7 determines the presence or absence of a forward vehicle from the received light signal data. The presence of the forward vehicle is determined using the reflection intensity from the reflector of the forward vehicle B in FIG. If it is determined that there is no vehicle ahead, the scan mode is continued. When it is determined that there is a vehicle ahead, the mode is switched to tracking mode. On the other hand, in the tracking mode, a constant voltage signal is applied to the light deflection element, and laser light is emitted to the reflector of the vehicle ahead. When two reflectors B1 and B2 are detected in the front vehicle B, the reflector with the larger received light signal amount is tracked. The distance / speed difference calculation unit 231 of the main control unit 230 calculates the inter-vehicle distance and the speed difference from the time difference between the stop pulse and the start pulse of the laser beam.

Next, the mode switching operation in the laser radar system of the present embodiment will be described with reference to FIG.
In order to search for a vehicle ahead, a linear voltage signal as shown in FIG. 11 is applied to the light deflection element in the scan mode, and the laser light is line-scanned (step S101). The received light intensity of the relatively high reflection intensity from the two locations of the reflectors B1 and B2 of the forward vehicle B in FIG. 9 is compared with the threshold value Ith, and when the received light intensity is greater than the threshold value Ith, it is determined that the forward vehicle is present ( Step S102; YES). Then, the scan mode is shifted to the tracking mode, and the vehicle ahead is tracked (steps S103 and S104). At this time, as shown in FIG. 12, one direction from the center B1-a of the reflector B1 of the front vehicle B being tracked, two directions from the two locations B1-b and B1-c around the reflector B1, Pulse laser light is emitted for a certain time in a total of three directions. The output time in each direction is 11.11 [ms]. The deflection angle to B1-a is θ and is the angle at which the reflector is detected in the scan mode. The minute deflection angle Δθ to the two surrounding locations B1-b and B1-c is 3 °. Here, FIG. 13 is a diagram showing the change with time of the applied voltage of the light polarizing element in three directions.

  The laser radar system of the present embodiment can acquire received light signals from three directions at intervals of 33.33 [ms] (step S105). When the received light intensity from the reflector is I (θ), in such a tracking mode, for example, as shown in FIG. 12, I (θ)> I (θ−Δθ) and I (θ)> I (θ + Δθ) If so (step S106; YES, step S107; YES), the distance and speed are calculated from the time difference between the start pulse and the stop pulse (step S108), displayed on the display in the vehicle, and irradiated with laser light in front. Keep track of the vehicle. For example, when the forward vehicle B moves in the left-right direction with respect to the own vehicle A, if I (θ) <I (θ−Δθ) or I (θ) <I (θ + Δθ) (step S106; NO, step S107) NO), it is determined that the forward vehicle B has moved in the left-right direction relative to the own vehicle A, and the main deflection angle θ is corrected so that θ → θ + Δθ or θ−Δθ (step S109).

  When the forward vehicle B moves in the right direction relative to the own vehicle A as shown in FIG. 14, I (θ) <I () at 300 [ms] in FIG. θ−Δθ). In addition, when I (θ) <Ith and I (θ−Δθ) <Tth are satisfied, another vehicle has entered between the front vehicle B and the own vehicle A, or the front vehicle B is turned right or left. It is determined that the tracked object has been lost, and the tracking mode is switched to the scan mode (step S110; YES). The tracking mode is continued until I (θ) <Ith and I (θ−Δθ) <Tth are satisfied.

  In addition, although embodiment mentioned above is a primary laser radar system, a two-dimensional laser radar system can obtain not only distance information but height information. Similar to the one-dimensional laser radar system, the light source uses a semiconductor laser of 850 [nm] to 1000 [nm], and both the X-direction light deflection element and the Z-direction light deflection element are electro-optic elements. A λ / 2 deflection plate is installed between the X-direction light polarization element and the Z-direction light deflection element, and the polarization direction incident on both the light deflection elements is P-polarized light. A galvanometer mirror or a MEMS mirror can also be used as the Z-direction light deflection element.

  As described above, according to the embodiment, as shown in FIG. 7, the laser light emitted from the light emitting unit 10 and the light emitting element 11 is light deflected using an electro-optic crystal as shown in FIGS. The element 21 is changed to a predetermined deflection angle and scanned. In the scan mode, scanning is performed in a wide deflection range by the optical deflection element 21 using an electro-optic crystal. Reflected light from the object is received by the light receiving element 31 to capture the object. The time until light is received by the time measurement unit 220 is measured, and the distance to the object and the speed difference are calculated by the distance / speed difference calculation unit 231 based on this time. On the other hand, in the tracking mode switched from the scan mode, the optical deflection element 21 performs deflection scanning with a deflection angle smaller than that in the scan mode. A plurality of reflected lights from the object are received by the light receiving element, and the object is tracked. The moving direction of the object can be detected by the intensity change of the plurality of reflected lights. Thereby, it is possible to provide a laser radar system that can accurately track an object with simple processing.

  Then, the deflection angle of the light deflection element is corrected based on the signal information of the laser beam reflected from the object of the laser beam by the deflection scanning with the minute deflection angle by the light deflection element 21. The object can be tracked with higher accuracy.

  In addition, according to the embodiment, it is desirable to use any one of lithium niobate, magnesium oxide-added lithium niobate, and lithium tantalate for the electro-optic crystal used in the light deflection element 21. Thereby, size reduction can be achieved.

  Furthermore, according to the embodiment, it is possible to construct a two-dimensional laser radar system by providing another deflecting unit that deflects light perpendicular to the optical deflecting unit 20.

  In addition, according to the embodiment, a laser radar system is mounted on the vehicle, the vehicle ahead can be captured and tracked with high accuracy, accidents such as rear-end collisions can be avoided, and the vehicle can be applied to a driving support device.

DESCRIPTION OF SYMBOLS 1 Laser radar system 10 Light emission part 11 Light emission element 12 Light emission circuit 13 Light source 14 Collimating lens 20 Light deflection part 21 Light deflection element 22 Light deflection circuit 23 Condensing lens 24 Light deflection element 24-1 Optical waveguide layer 24-2 Upper electrode 24 -3 Lower electrode 24-4 Electro-optic prism 25 Collimating lens 26 Angle-of-view lens 30 Light receiving unit 31 Light receiving element 32 Light receiving circuit 33 Light blocking filter 34 Condensing lens 100 Laser radar module 200 Signal processing unit 210 Pulse generation unit 220 Time measuring unit 230 Main Control Unit 231 Distance / Differential Speed Calculation Unit 232 Scan Mode / Tracking Mode Switching Discrimination Unit 233 Alarm Discrimination Unit 300 Alarm Unit 400 Display Unit 500 Power Supply

JP-A-8-62333

Claims (6)

Light emitting means for irradiating a moving object with laser light, light deflecting means for scanning the laser light by changing a deflection angle of the laser light emitted by the light emitting means, and receiving laser light reflected from the object Receiving light means, driving means for driving the light receiving means, laser light emitted from the light emitting means is deflected and scanned by the light deflecting means, and reflected light from the object is received by the light receiving means. A laser radar module having switching means for switching between a scan mode for capturing an object and a tracking mode for receiving reflected light from the object by the light receiving means and tracking the object;
A light emission signal supply unit that supplies a light emission signal to the light emission means, the laser beam irradiated by the light emission means, and a laser beam that is irradiated toward the object and reflected from the target object. A signal processing unit having a distance difference speed calculation unit for calculating a distance to and a difference speed,
In the laser radar system that detects the presence or absence of the object, the distance to the object and the differential speed,
In the tracking mode, the laser beam emitted from the light emitting unit is deflected and scanned by the light deflecting unit with a deflection angle smaller than that in the scan mode, and a plurality of reflected lights from an object are received by the light receiving unit. A laser radar system characterized by receiving light and tracking an object. The laser radar system according to claim 1, wherein
A deflection angle correction unit that corrects the deflection angle of the light deflection unit based on the signal information of the laser beam reflected from the laser beam object by deflection scanning at a minute deflection angle by the light deflection unit is provided. Laser radar system. The laser radar system according to claim 1 or 2,
The laser beam radar system according to claim 1, wherein the light deflection unit includes a light deflection element using an electro-optic crystal in which a prism type polarization inversion region is formed. The laser radar system according to claim 3, wherein
2. The laser radar system according to claim 1, wherein the electro-optic crystal is any one of lithium niobate, magnesium oxide-added lithium niobate, and lithium tantalate. The laser radar system according to any one of claims 1 to 3,
A laser radar system comprising a deflecting means for deflecting the laser beam perpendicularly to the light deflecting means.   A moving body comprising the laser radar system according to any one of claims 1 to 5.

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