JP2017049230A - Laser radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser radar device that suppresses a mist from being detected, and can detect an object of low reflectance to be detected.SOLUTION: A laser radar device comprises: a detection performance level setting unit 81 that selects a detection performance level expressing easiness to detect objects from a high detection performance level serving a detection performance level capable of detecting a low reflection detection object and a low detection performance level serving a detection performance level not detecting the low reflection detection object, and set the selected detection performance level; a low detection performance measurement unit 83 that sets the detection performance level to the low detection performance level, and scans laser light to receive reflection light; a low detection performance object determination unit 85 that determines whether an object exists from a measurement result of the low detection performance measurement unit 83; a high detection performance measurement unit 84 that sets the detection performance level to the high detection performance level, and scans the laser light to receive the reflection light; and a high detection performance object determination unit 86 that, when a waveform width of the reflection light measured by the high detection performance measurement unit 84 is shorter than a mist determination width threshold with respect to a direction where the low detection performance object determination 85 does not determine the existence of the object, determines existence of the object.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a laser radar device, and more particularly to a technique for detecting an object having a low reflectance.

  The laser radar device irradiates laser light to the outside of the device, and receives reflected light generated by the laser light being reflected by an object outside the device. Based on the intensity of the reflected light, it is determined whether an object is present, and the distance to the object is calculated from the time until the reflected light is received. As described in Patent Document 1, the laser radar device detects whether or not an object exists in the monitoring area by scanning the laser beam.

JP 2008-216238 A

  The laser radar device does not need to detect fog. However, laser light is reflected even in fog. However, since the mist has a space between the particles, the reflectance for reflecting the laser beam is low. In the present specification, the reflectance is the ratio of the laser light applied to the object and the reflected light reflected in the direction of the laser radar device.

  Since the reflectance of fog is low, it is conceivable to reduce the light receiving sensitivity in order to suppress the detection of fog. When the light receiving sensitivity is lowered, the intensity of reflected light from an object with low reflectance is unlikely to exceed the threshold value for determining that the object has been detected. Therefore, it can suppress detecting fog.

  However, there are objects with low reflectivity other than fog. For example, a black object has a low reflectance. An object whose surface is a mirror surface also has a low reflectance. Therefore, an object having a black color and a mirror surface is particularly low in reflectance. An example of such an object is a black car.

  When the laser radar device needs to detect an object with low reflectance that is not fog, there is a problem that if the light receiving sensitivity is lowered, it becomes difficult to detect an object with low reflectance to be detected.

  The present invention has been made based on this situation, and an object of the present invention is to provide a laser radar device that can detect a low-reflectance object to be detected while suppressing the detection of fog. It is to provide.

  The above object is achieved by a combination of the features described in the independent claims, and the subclaims define further advantageous embodiments of the invention. Reference numerals in parentheses described in the claims indicate a correspondence relationship with specific means described in the embodiments described later as one aspect, and do not limit the technical scope of the present invention. .

The present invention for achieving the above object includes a light projecting unit (10) for generating and projecting laser light,
A scanning unit (50, 60) for irradiating the laser light projected by the light projecting unit to the outside of the apparatus while changing the irradiation direction;
A light receiving unit (20, 120H, 120L) that receives the reflected light generated by the laser beam irradiated to the outside of the apparatus by the scanning unit;
A laser radar device (1, 100) having a measuring unit (4, 104) comprising:
The detection performance level indicating the ease of detection of an object determined by the intensity of the laser light projected by the light projecting unit and the light receiving sensitivity by which the light receiving unit receives reflected light is a preset detection target object with low reflectance. High detection performance level that can be detected when the low reflection detection target object is at the reference angle with respect to the laser radar device at the reference distance, and the reference angle with respect to the laser radar device at the reference distance The detection target object is detected at two detection performance levels, ie, a low detection performance level that does not detect the low reflection detection target object,
A low detection performance measurement unit that performs a low detection performance measurement process in which a laser beam is irradiated to the outside of the apparatus while the irradiation direction is changed by the scanning unit and a reflected light is received by the light receiving unit. 83, 183),
The low detection performance measurement unit executes the low detection performance measurement process, and based on the reflected light received by the light receiving unit, the low detection performance measurement process determines whether or not an object exists in the direction in which the laser beam is irradiated. A low detection performance object determination unit (85);
In the measurement unit with a high detection performance level, the low detection performance object determination unit irradiates the laser beam with the scanning unit in the direction including at least the direction in which the object is not determined to be present, and reflects the reflected light at the light reception unit. A high detection performance measurement unit (84, 184) for executing high detection performance measurement processing for receiving light;
For the direction in which the low detection performance object determination unit did not determine that an object is present, the waveform width of the reflected light received by the light receiving unit when the high detection performance measurement unit executes the high detection performance measurement process is the fog determination width threshold And a high detection performance object determination unit (86) for determining that an object is present based on the fact that the object is shorter.

  In the present invention, the measurement unit detects the detection target object with two detection performance levels, ie, a high detection performance level and a low detection performance level, representing the detection performance level indicating the ease of detecting the object. The high detection performance level is a detection performance level that can be detected when a low reflection detection target object, which is a preset detection target object with low reflectance, is at a reference angle with respect to the laser radar device at a reference distance. On the other hand, the low detection performance level is a detection performance level that does not detect the low reflection detection target object that is at the reference angle with respect to the laser radar device at the reference distance.

  The low detection performance measurement unit is a measurement unit at a low detection performance level, and executes low detection performance measurement processing in which reflected light is received by the light receiving unit while changing the irradiation direction of the laser light. The low detection performance object determination unit determines whether there is an object in the direction in which the laser beam is irradiated based on the reflected light received by the light receiving unit by executing the low detection performance measurement process. If the detection performance level is a low detection performance level, an object with low reflectance is difficult to detect. Therefore, the low detection performance object determination unit can suppress the detection of fog. However, there is a possibility that a low-reflectivity detection target object exists in the direction in which the low-detection performance object determination unit does not determine that an object exists.

  Therefore, in the present invention, for the direction in which the low detection performance object determination unit has not determined that the object exists, the high detection performance measurement unit and the high detection performance object determination unit further determine whether or not the object exists. To do.

  The high detection performance measurement unit is a measurement unit at a high detection performance level. The low detection performance object determination unit irradiates the reflected light by irradiating a laser beam in a direction including at least a direction in which the object is not determined to exist. Is received by the light receiving unit. By measuring at a high detection performance level, there is a possibility that reflected light having a level that is determined to be an object can be detected even in a direction that is not determined to be an object at a low detection performance level.

  When a reflected light with a level that is judged to be an object can be detected at a high detection performance level in a direction where it was not judged that an object exists at a low detection performance level, an object with a low reflectance exists in that direction. I understand that

  However, the low-reflectance object may be a fog or a detection target object. If the low reflectance object is fog, the present inventor has found that the reflected light waveform width measured by the high detection performance measurement process is significantly wider than when the low reflectance object is the detection target object. I found it.

  Fog is a configuration in which many water particles floating in the air exist in the direction of laser light, and the laser light irradiated to the mist may be transmitted through water particles or reflected by water particles. There is also. Therefore, the laser light irradiated on the fog repeats transmission and reflection. Thereby, it is considered that the waveform width of the reflected light is widened. On the other hand, if the low reflectance object is a detection target object, the laser beam is only reflected once on the object surface. Therefore, if the low reflectance object is fog, the reflected light waveform width measured by the high detection performance measurement process will be significantly wider than when the low reflectance object is the detection target object. It is done.

  Using this, the high detection performance object determination unit executes the high detection performance measurement process by the high detection performance measurement unit for the direction in which the low detection performance object determination unit did not determine that the object exists. Based on the fact that the waveform width of the reflected light detected by the light receiving unit is shorter than the fog determination width threshold value, it is determined that an object is present. By doing in this way, the object of the low reflectance which should be detected can be detected, suppressing detecting fog.

The invention according to claim 2 includes a detection performance level setting unit (81) for setting a high detection performance level and a low detection performance level by changing at least one of the intensity of the laser beam and the light receiving sensitivity.
The low detection performance measurement unit (83) executes the low detection performance measurement process by setting the detection performance level of the measurement unit to the low detection performance level by the detection performance level setting unit,
The high detection performance measurement unit (84) executes the high detection performance measurement process by setting the detection performance level of the measurement unit to the high detection performance level by the detection performance level setting unit.

  In this way, the measurement unit can realize a high detection performance level and a low detection performance level by a single light receiving unit.

  In the invention according to claim 3, the detection performance level setting unit changes the intensity of the laser light projected by the light projecting unit, while the light receiving sensitivity at which the light receiving unit receives the reflected light is not changed, and the low detection performance level is set. And set high detection performance level.

  In this way, when setting the detection performance level by changing the detection performance level according to the intensity of the laser light projected by the light projecting unit, compared with the case where the same high detection performance level is set by changing the light receiving sensitivity. Thus, the light receiving sensitivity can be lowered. Since the influence of disturbance light can be suppressed as the light receiving sensitivity is low, the influence of disturbance light can be suppressed in this way.

In the invention which concerns on Claim 4, a light-receiving part is provided with the 1st light-receiving part (120H) and 2nd light-receiving part (120L) which are arrange | positioned in a mutually different position and light-receives reflected light,
The measurement unit (104) detects the reflected light at a division ratio such that the first light receiving unit detects the detection target object at a high detection performance level and the second light reception unit detects the detection target object at a low detection performance level. A beam splitter (135) for splitting is provided.

  In this way, the measurement at the high detection performance level and the measurement at the low detection performance level can be performed by the same scanning of the laser beam. Therefore, compared with the case where the measurement at the high detection performance level and the measurement at the low detection performance level are performed by scanning with different laser beams, the cycle in which the high detection performance object determination unit performs determination, that is, the object detection cycle is shortened. can do.

  In addition, a high detection performance level and a low detection performance level can be realized without changing the light receiving sensitivity of the first light receiving unit and the second light receiving unit and the intensity of the laser beam. Therefore, there is an advantage that it is not necessary to provide a configuration for changing the intensity of the laser light or a configuration for changing the light receiving sensitivity.

  In the invention according to claim 5, the high detection performance object determination unit performs the high detection performance measurement process by the high detection performance measurement unit for a single direction in which the low detection performance object determination unit has not determined that the object exists. When there is a section exceeding two object determination thresholds in the reflected light detected by the light receiving unit by executing, it is determined that there is an object without comparing the waveform width of the reflected light with the fog determination width threshold.

  In this way, it is not necessary to compare the waveform width and the fog determination width threshold value, and therefore processing for determining the waveform width and processing for comparing the waveform width with the fog determination width threshold value are not required. Therefore, the determination result that the object exists is quickly obtained. Moreover, when the length of the fog in the laser beam irradiation direction is not so long, the waveform width may not be so wide even in the reflected light generated by the reflection from the fog. Even in such a case, since it can be determined that it is fog, detection of fog can be further suppressed.

It is a figure which shows the internal structure of the laser radar apparatus 1 of 1st Embodiment. It is a figure which shows the structure of the circuit part 70 of FIG. 1 in detail. It is a figure which shows the structure of the control part 80 of FIG. 2 in detail. It is a figure which shows the repetition of the low detection performance measurement process and the high detection performance measurement process which the measurement process part 82 of FIG. 3 performs. It is a figure which shows the difference of the object which can be detected with a low detection performance level and a high detection performance level. It is a figure explaining the process of the low detection performance object determination part 85, the high detection performance object determination part 86, and the ranging part of FIG. It is a figure explaining which measurement data is used for a low detection performance level and a high detection performance level in a specific situation example. In the laser radar apparatus 100 of 2nd Embodiment, it is a figure explaining a different structure from the laser radar apparatus 1 of 1st Embodiment. It is a block diagram which shows the structure of the circuit part 170 of FIG. It is a block diagram which shows the structure of the control part 180 of FIG.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the laser radar device 1 of the first embodiment includes a laser diode 10 that is a light projecting unit, and a photodiode 20 that is an example of a light receiving unit that receives reflected light L1 from an object outside the device. The distance and direction to the object outside the apparatus are detected. The laser radar device 1 is installed outdoors and detects an object that moves within the monitoring area of the laser radar device 1. An object to be detected (hereinafter, a detection target object) is a moving body other than a particulate suspended matter. For example, the detection target object includes a person and a vehicle on which the person is boarded.

  In FIG. 1, a laser diode 10 projects pulsed laser light (hereinafter referred to as irradiation light L0). The photodiode 20 detects the reflected light L1 generated by the irradiation light L0 being reflected by an object outside the apparatus and converts it into an electrical signal.

  A collimating lens 30 and a perforated mirror 40 are provided on the optical axis of the laser diode 10. The collimating lens 30 converts the irradiation light L0 projected by the laser diode 10 into parallel light.

  The perforated mirror 40 has a flat plate shape and is disposed on the optical axis of the laser diode 10 at an angle with respect to the optical axis. The lower surface of the perforated mirror 40 is a reflecting surface 41, and a through hole 42 penetrating in the vertical direction is formed at the center of the perforated mirror 40. The perforated mirror 40 is arranged so that the through hole 42 is positioned on the optical axis of the laser diode 10.

  A rotating mirror 50 is provided on the optical axis of the irradiation light L0 passing through the perforated mirror 40. The rotating mirror 50 is disposed so as to be rotatable about a central axis extending in the optical axis direction of the laser diode 10, and deflects the irradiation light L0 by a concave mirror 51 whose focal position is set on the central axis. The irradiation light L0 is irradiated toward the outside of the apparatus. The concave mirror 51 deflects the reflected light L1 in the direction of the perforated mirror 40.

  The motor 60 rotates the rotating shaft 61 to rotate the rotating mirror 50 connected to the rotating shaft 61. The rotating shaft 61 is a rotating shaft of the motor 60, and the rotating mirror 50 is rotated by the rotation of the rotating shaft 61. When the irradiation light L0 sequentially enters the concave mirror 51 while the rotating mirror 50 is rotated by the motor 60, the irradiation light L0 is irradiated to the outside of the apparatus while the irradiation direction changes according to the rotation of the rotating mirror 50. The The rotating mirror 50 and the motor 60 correspond to a scanning unit. The measuring unit 4 includes a laser diode 10 corresponding to a light projecting unit, a rotary mirror 50 and motor 60 corresponding to a scanning unit, and a photodiode 20 corresponding to a light receiving unit.

  The rotation angle position sensor 62 detects the rotation angle position of the rotation shaft 61, that is, the rotation angle position of the concave mirror 51. Various types of rotation angle position sensor 62 can be used as long as the rotation angle position of the rotation shaft 61 can be detected, such as a rotary encoder.

  The circuit unit 70 has a configuration shown in FIG. These configurations are accommodated in an apparatus internal space formed by the housing 2 and the housing window 3. The housing 2 has a box shape in which a portion to which the housing window 3 is attached is opened. The housing window 3 is made of a light transmissive member and is attached to the housing 2. The range around the horizontal plane to which the housing window 3 is attached is a scan angle range or an angle range larger than the scan angle range with the front direction of the laser radar device 1 as the center. The scanning angle range is, for example, 190 degrees. The front direction of the laser radar device 1 is a direction from the inside of the laser radar device 1 toward the housing window 3 in a vertical section that bisects the housing window 3.

  As shown in FIG. 2, the circuit unit 70 includes an LD drive circuit 71, an amplifier 72, a motor drive circuit 73, a storage unit 74, and a control unit 80. The LD drive circuit 71 is a circuit that drives the laser diode 10. The amplifier 72 amplifies the electrical signal output from the photodiode 20 and outputs the amplified signal to the control unit 80. The motor drive circuit 73 is a circuit that outputs a current to the motor 60 to rotate the motor 60. The storage unit 74 has a rewritable configuration, and is used by the measurement processing unit 82, the low detection performance object determination unit 85, and the high detection performance object determination unit 86 described later.

  The control unit 80 includes circuits such as a CPU, ROM, RAM, ASIC, CPLD, and comparator. In the control unit 80, for example, the CPU executes various functions using part or all of the circuit, such as executing a program stored in the ROM while using the temporary storage function of the RAM.

  For example, the control unit 80 outputs a light emission command to the LD drive circuit 71 and causes the laser diode 10 to generate laser light in a pulse shape. The light emission command includes information indicating a drive voltage value, and the LD drive circuit 71 generates laser light from the laser diode 10 at a drive voltage value determined by the light emission command. The higher the driving voltage value, the stronger the laser diode 10 generates laser light. Further, the control unit 80 acquires the detection value of the rotation angle position sensor 62 and detects the rotation position and rotation speed of the rotary mirror 50. In addition, a motor drive signal that instructs the motor drive circuit 73 to rotate the motor 60 at a predetermined speed is output.

  Furthermore, the control unit 80 also functions as each unit shown in FIG. That is, the control unit 80 also functions as a detection performance level setting unit 81, a measurement processing unit 82, a low detection performance object determination unit 85, a high detection performance object determination unit 86, and a distance measurement unit 87.

  The detection performance level setting unit 81 selects and sets the detection performance level of the laser radar device 1 from the high detection performance level and the low detection performance level. The detection performance level is an index representing the ease of detecting an object. Since the intensity of the reflected light L1 from the same object at the same distance increases as the intensity of the irradiation light L0 increases, the intensity of the reflected light L1 tends to exceed the object detection threshold for determining that the object has been detected. Therefore, the stronger the intensity of the irradiation light L0, the easier it is to detect the object.

  Even if the reflected light L1 having the same intensity is received, the higher the light receiving sensitivity of the photodiode 20, the more easily the intensity of the reflected light L1 exceeds the object detection threshold for determining that an object has been detected. The higher the sensitivity, the easier it is to detect the object. Therefore, the detection performance level is determined by the product of the intensity of the irradiation light L0 and the light receiving sensitivity of the photodiode 20. Note that the light receiving sensitivity of the photodiode 20 is determined by the amplification factor of the amplifier 72.

  The high detection performance level in the present embodiment is 45 with respect to the irradiation direction of the irradiation light L0 at a position 5 m away from the laser radar apparatus 1 when a black flat glass-coated metal plate (hereinafter referred to as a black flat plate). This is a detection performance level at which the black flat plate can be detected in a tilted state. The black flat plate is an object simulating a black vehicle body. In the present embodiment, the black flat plate is a low reflection detection target object. Further, 5 m is a reference distance, 45 degrees is a reference angle, and a measurement condition that is a reference angle at the reference distance is a reference measurement condition.

  The low detection performance level is a detection performance level at which the black flat plate that is the reference measurement condition cannot be detected. However, this low detection performance level is a detection performance level that does not detect fog with a predetermined visibility. The predetermined visibility is 20 m, for example. The high detection performance level described above can detect a black flat plate under the reference measurement conditions, but detects a fog that is not detected at the low detection performance level.

  In the present embodiment, the detection performance level setting unit 81 controls the drive voltage value output from the LD drive circuit 71 to change the intensity of the irradiation light L0 output from the laser diode 10, thereby increasing the detection performance level. Set the low detection performance level. For example, the intensity of the irradiation light L0 at the high detection performance level is set to 10 to 20 times the intensity of the irradiation light L0 at the low detection performance level.

  The measurement processing unit 82 includes a low detection performance measurement unit 83 and a high detection performance measurement unit 84. The low detection performance measurement unit 83 executes low detection performance measurement processing. The low detection performance measurement process is a process in which the measurement unit 4 having a low detection performance level scans the monitoring area with the irradiation light L0 and receives the reflected light L1. In the first embodiment, in order to set the measurement unit 4 to the low detection performance level, the detection performance level setting unit 81 sets the detection performance level to the low detection performance level.

  Similar to the scanning angle range, the monitoring area is an angle range of ± 95 degrees centering on the front direction of the laser radar apparatus 1 and a total of 190 degrees, and the distance from the laser radar apparatus 1 is, for example, a range of 30 m. In order to detect the detection target object existing in the monitoring area, the rotating mirror 50 is rotated by the motor 60, thereby changing the irradiation direction of the irradiation light L0 within the scanning angle range, and the irradiation light L0. Irradiate outside. Then, the reflected light L1 is received by the photodiode 20. The received reflected light L1 is input to the control unit 80 via the amplifier 72. The low detection performance measuring unit 83 compares the input signal intensity of the reflected light L1 with the object detection threshold, and when the signal intensity of the reflected light L1 exceeds the object detection threshold, the signal intensity of the reflected light L1 detects the object. The time below the threshold is stored in the storage unit 74 in association with the irradiation direction of the irradiation light L0.

  The high detection performance measurement unit 84 executes high detection performance measurement processing. The high detection performance measurement process is the same process as the low detection performance measurement process except that measurement is performed by the measurement unit 4 having a high detection performance level. In the first embodiment, in order to set the measurement unit 4 to the high detection performance level, the detection performance level setting unit 81 sets the detection performance level to the high detection performance level.

  The measurement processing unit 82 alternately repeats the low detection performance measurement process by the low detection performance measurement unit 83 and the high detection performance measurement process by the high detection performance measurement unit 84. FIG. 4 is a diagram illustrating repetition of the low detection performance measurement process and the high detection performance measurement process executed by the measurement processing unit 82. As shown in FIG. 4, in the low detection performance measurement process, the detection performance level is set to the low detection performance level, and in the high detection performance measurement process, the detection performance level is set to the high detection performance level. In any process, the light emission pulse, that is, the pulsed irradiation light L0 is emitted at a constant angle (when the rotation angle θ of the rotary mirror 50 is −95 ° to 95 ° corresponding to the angle range of the monitoring area). For example, every 0.25 degrees.

  The low detection performance object determination unit 85 acquires, from the storage unit 74, the reflected light L1 received by the photodiode 20 together with the irradiation direction when the low detection performance measurement unit 83 executes the low detection performance measurement process. For the irradiation direction in which the intensity of the acquired reflected light L1 exceeds the object determination threshold, it is determined that there is an object in that direction, and there is an object in the irradiation direction in which the intensity of the reflected light L1 does not exceed the object determination threshold. Judge that not. Then, the storage unit 74 stores the direction in which it is not determined that the object exists.

  The high detection performance object determination unit 86 determines whether or not an object exists in a direction in which the low detection performance object determination unit 85 stored in the storage unit 74 has not determined that an object exists. The determination method is as follows. First, the signal intensity of the reflected light L1 when the high detection performance measurement process is executed in the direction in which the low detection performance object determination unit 85 stored in the storage unit 74 has not determined that the object exists is the object detection. The time exceeding the threshold and the time falling below the object detection threshold are acquired from the storage unit 74. The waveform width is defined from the time when the signal intensity of the reflected light L1 exceeds the object detection threshold to the time when it falls below the object detection threshold when the high detection performance measurement process is executed.

  In the reflected light L1 obtained with respect to a single irradiation direction, when there are two peaks that can calculate the waveform width, an object exists in the irradiation direction stored corresponding to the reflected light L1. Judge that. This is because when there are two peaks whose waveform width can be calculated, the first peak is caused by fog, but the second peak is considered to be a detection target object.

  Further, in the reflected light L1 obtained with respect to a single irradiation direction, there is one peak that can calculate the waveform width, and even when the waveform width is shorter than the fog determination width threshold, it corresponds to the reflected light L1. It is determined that an object exists in the stored irradiation direction. On the other hand, if there is one peak from which the waveform width can be calculated and the waveform width is equal to or greater than the fog determination width threshold, it is determined that the object present in the irradiation direction is fog.

  This fog determination width threshold is a threshold set based on the knowledge that the waveform width of the fog is significantly wider than the waveform width of the black flat plate, which is a low reflection detection target object, when measured by the high detection performance measurement process. .

  In the low detection performance measurement process, the waveform width of the reflected light L1 from the detection target object having a low reflectance is also widened so as to be difficult to distinguish from fog. In the low detection performance measurement process, a low detection performance level is set. The low detection performance level is low because the intensity of the irradiation light L0 is high, the light receiving sensitivity of the photodiode 20 is high, or both. Even the reflected light L1 from the reflection detection target object has a high signal intensity. As a result, the waveform width is wide even for the reflected light L1 from the low reflection detection target object.

  In the low detection performance measurement process, the waveform width of the reflected light L1 from the detection target object having a low reflectance is also widened to be difficult to distinguish from fog. Therefore, in the present embodiment, the low detection performance object determination unit 85 determines whether or not an object exists in the high detection performance object determination unit 86 only in the direction in which it is not determined that the object exists.

  FIG. 5 is a diagram summarizing differences in detectable objects between the low detection performance level and the high detection performance level. In FIG. 5, the detection target object having a high reflectance is, for example, a person. As shown in FIG. 5, at a low detection performance level, a detection target object having a high reflectance can be detected, but a detection target object having a low reflectance cannot be detected. However, at the low detection performance level, erroneous detection of fog as a detection target object can be suppressed.

  On the other hand, at a high detection performance level, it is possible to detect a detection target object having a low reflectance. However, fog is also detected at a high detection performance level. However, the waveform width at the high detection performance level is different in that the detection target object with low reflectance is narrow and the fog is wide. Using this difference, it is determined whether it is fog or a low-reflectance detection target object.

  Returning to FIG. The distance measuring unit 87 calculates a distance to an object existing in the monitoring area. The processing of the distance measuring unit 87 will be described with reference to FIG. In FIG. 6, steps S4 and S5 are processes of the distance measuring unit 87, step S1 is a process of the low detection performance object determination unit 85, and steps S2 and S3 are processes of the high detection performance object determination unit 86.

  The process shown in FIG. 6 is a process executed after one low detection performance measurement process by the low detection performance measurement unit 83 and one subsequent high detection performance measurement process by the high detection performance measurement unit 84 are completed. Yes, the processing of FIG. 6 is executed for every scanning angle within the scanning angle range.

  In step S1, it is determined whether distance measurement is possible at a low detection performance level. In other words, this determination is to determine whether or not the low detection performance object determination unit 85 determines that an object exists. If judgment of step S1 is NO, it will progress to step S2.

  In step S2, it is determined whether or not there are two peaks exceeding the object determination threshold in the measurement data at the high detection performance level. If this determination is YES, a low-reflectance detection target object exists. If judgment of step S2 is YES, it will progress to step S5. On the other hand, if the determination in step S2 is NO, the process proceeds to step S3.

  In step S3, it is determined whether or not the measurement data measured at the high detection performance level includes data whose waveform width is equal to or greater than the fog determination width threshold. If the determination in step S3 is YES, it is considered that the reflected light L1 detected at the high detection performance level is the reflected light L1 generated by fog. If judgment of step S3 is YES, it will progress to step S4. On the other hand, if the determination in step S3 is NO, it can be estimated that no fog has been detected. If judgment of step S3 is NO, it will progress to step S5.

  In step S4, the distance to the object is calculated using the measurement data at the low detection performance level. Step S4 is executed when the determination at step S1 is YES or when the determination at step S3 is YES. When the determination in step S1 is YES, it is determined that an object exists. When it is determined that an object exists, the distance to the object is calculated from the time from the irradiation of the irradiation light L0 to the reception time of the reflected light L1 exceeding the object determination threshold. The light reception time of the reflected light L1 exceeding the object determination threshold is, for example, the time when the intensity of the reflected light L1 first exceeds the object determination threshold. Further, the intermediate time during the period when the intensity of the reflected light L1 exceeds the object determination threshold may be set as the time when the object determination threshold is exceeded.

  When fog is generated and a detection target object (for example, a person) is present in the fog, there may be two sections where the intensity of the reflected light L1 exceeds the object determination threshold. Part of the irradiation light L0 is reflected by the fog, and the reflected light L1 generated by the reflection by the fog exceeds the object determination threshold, and the reflected light L1 generated by passing through the fog and reflected by the detection target object is also the object determination threshold. It is because it may exceed.

  When there are two sections in which the intensity of the reflected light L1 exceeds the object determination threshold, the distance to the object is calculated later using the section exceeding the object determination threshold. When there are two sections in which the intensity of the reflected light L1 exceeds the object determination threshold, an object behind the fog can be seen through the fog. This is because the section exceeding the front object determination threshold is considered to be reflected light L1 due to fog, and the section exceeding the object determination threshold later is considered to be reflected light L1 due to the detection target object.

  If the determination in step S3 is YES and step S4 is executed, it is determined that there is no object from the measurement data of the low detection performance level, and therefore the distance to the object is not calculated.

  In step S5, the distance to the object is calculated using the measurement data at the high detection performance level. Step S5 is executed when the determination at step S2 is YES or when the determination at step S3 is YES. When the determination in step S2 is YES, the high detection performance object determination unit 86 determines that the detection target object exists. In this case, the distance to the object is calculated in the same manner as in step S4 executed when the determination in step S1 is YES. Therefore, as in step S4, when there are two sections in which the intensity of the reflected light L1 exceeds the object determination threshold, the distance to the object is calculated later using the section exceeding the object determination threshold.

  When the determination in step S3 is YES, the waveform width obtained at the high detection performance level does not exceed the fog determination width threshold, but the peak exceeding the object determination threshold can be detected with a time width that can be distinguished from noise. In some cases, a peak exceeding the object determination threshold cannot be detected. In the former case, the distance to the object is calculated as in step S4. In the latter case, the object does not exist, so the distance to the object is not calculated.

  FIG. 7 is a diagram for explaining whether measurement data with a low detection performance level or measurement data with a high detection performance level is used in a specific situation example. In FIG. 7, −95 degrees is the scanning start angle. There is no object from -95 degrees to angle θ1. Accordingly, steps S1, S2, and S3 are all NO, and the process proceeds to step S5. Therefore, measurement data at a high detection performance level is used. As a result, the distance to the object is not calculated.

  Steps S1, S2, and S3 are all NO between the angle θ1 and the angle θ2, and measurement data at a high detection performance level is used. However, between the angle θ1 and the angle θ2, the distance to the black car 90 is calculated by using the measurement data obtained at the high detection performance level.

  Between the angle θ2 and the angle θ3 is the same as −95 degrees to the angle θ1, and measurement data at a high detection performance level is used. Since there is no object, the distance to the object is not calculated.

  Between the angle θ3 and the angle θ4, the determination in step S1 is YES, and the process proceeds to step S4. Therefore, the distance to the pedestrian 92 is calculated using the measurement data of the low detection performance level.

  The angle θ4 to the angle θ5 is the same as −95 degrees to the angle θ1, and measurement data at a high detection performance level is used. Since there is no object, the distance to the object is not calculated.

  Between the angle θ5 and the angle θ6, the fog 94 exists but no other object exists. Accordingly, the determinations in steps S1 and S2 are NO, the determination in step S3 is YES, and the process proceeds to step S4. Therefore, measurement data with a low detection performance level is used. In the measurement data of the low detection performance level, since the fog 94 is not detected, the distance to the object is not calculated.

  The fog 94 exists between the angle θ6 and the angle θ7, but the pedestrian 96 exists in the fog 94. In the measurement data at the low detection performance level, the fog 94 is not detected, but the pedestrian 96 is detected. Accordingly, the determination in step S1 is YES, and the process proceeds to step S4. Therefore, the distance to the pedestrian 96 is calculated using the low detection performance level data.

  The angle θ7 to the angle θ8 is the same as the angle θ5 to the angle θ6, and measurement data with a low detection performance level is used. Therefore, since the fog 94 is not detected, the distance to the object is not calculated.

  The angle θ8 to 95 degrees is the same as the angle −95 degrees to the angle θ1, and measurement data at a high detection performance level is used. Since there is no object, the distance to the object is not calculated.

  As described above, in the laser radar device 1 of the present embodiment described above, the detection performance level setting unit 81 can select and set the detection performance level representing the ease of detecting an object from the high detection performance level and the low detection performance level. . The high detection performance level is a detection performance level at which a black flat plate can be detected under reference measurement conditions, and the low detection performance level is a detection performance level at which a black flat plate is not detected under reference measurement conditions.

  The low detection performance measurement unit 83 sets the detection performance level to the low detection performance level, and executes the low detection performance measurement process in which the photodiode 20 receives the reflected light L1 while changing the irradiation direction of the irradiation light L0. . The low detection performance object determination unit 85 executes the low detection performance measurement process, and the direction in which the irradiation light L0 is irradiated depends on whether the intensity of the reflected light L1 acquired from the photodiode 20 exceeds the object determination threshold. It is determined whether or not an object exists.

  If the detection performance level is a low detection performance level, an object with low reflectance is difficult to detect. Therefore, as shown in FIG. 5, detection of fog can be suppressed when measurement is performed at a low detection performance level. However, there is a possibility that a low-reflectivity detection target object exists in the direction in which the low-detection performance object determination unit 85 has not determined that an object exists.

  Therefore, in the present embodiment, in the direction in which the low detection performance object determination unit 85 has not determined that an object exists, the high detection performance measurement unit 84 and the high detection performance object determination unit 86 have no object. Determine further.

  The high detection performance measurement unit 84 is the same process as the low detection performance measurement process except that the detection performance level is set to the high detection performance level. Even in a direction in which it is not determined that an object exists at the low detection performance level, if the reflected light L1 having an intensity equal to or higher than the object determination threshold is detected at the high detection performance level, an object having a low reflectance in that direction is detected. You can see that it exists. As shown in FIG. 5, this low reflectance object may be a fog or a detection target object. However, in the case of the reflected light L1 from the detection target object, the waveform width is narrowed. Accordingly, the high detection performance object determination unit 86 performs reflected light obtained from the photodiode 20 by executing the high detection performance measurement process for the direction in which the low detection performance object determination unit 85 has not determined that the object exists. When the waveform width of L1 is shorter than the fog determination width threshold, it is determined that a detection target object exists. By doing in this way, the laser radar apparatus 1 of this embodiment can detect the low-reflectance object which should be detected, suppressing detecting fog.

  In addition, the detection performance level setting unit 81 of the present embodiment sets the low detection performance level and the high detection performance level without changing the light receiving sensitivity of the photodiode 20 while changing the intensity of the irradiation light L0. Therefore, compared with the case where the same high detection performance level is set by changing the light receiving sensitivity, the light receiving sensitivity can be lowered. Therefore, the influence of disturbance light can be suppressed.

  In this embodiment, when it is determined that there are two or more peaks in the measurement data at the high detection performance level (S2: YES), is the waveform width obtained at the high detection performance level equal to or greater than the fog determination width threshold? It is determined that the detection target object exists without determining whether or not. Thereby, the process which determines a waveform width and the process which compares a waveform width with a fog determination width | variety threshold value become unnecessary. Therefore, a determination result that the detection target object exists is quickly obtained.

  Furthermore, at the initial stage of fog generation, the length of the fog in the irradiation direction of the irradiation light L0 may not be so long, and in this case, the waveform width of the reflected light L1 generated by reflection from the fog may not be so wide. There is also. However, even in such a case, it can be determined that it is fog by performing the determination in step S2, so that it is possible to further suppress detection of fog.

Second Embodiment
Next, a second embodiment will be described. In the following description of the second embodiment, elements having the same reference numerals as those used so far are the same as elements having the same reference numerals in the previous embodiments unless otherwise specified. Further, when only a part of the configuration is described, the above-described embodiment can be applied to the other parts of the configuration.

  As shown in FIG. 8, the laser radar device 100 of the second embodiment includes a photodiode 120 </ b> H, and includes a beam splitter 135 between the photodiode 120 </ b> H and the reflecting surface 41 of the perforated mirror 40. The laser radar device 100 according to the second embodiment also includes a photodiode 120L. The photodiode 120H corresponds to the first light receiving unit, and the photodiode 120L corresponds to the second light receiving unit. The measurement unit 104 according to the second embodiment includes photodiodes 120H and 120L instead of the photodiode 20 according to the first embodiment. The rest of the configuration of the measurement unit 104 is the same as that of the measurement unit 4 of the first embodiment.

  The photodiodes 120H and 120L are connected to the circuit unit 170. The configuration of the circuit unit 170 is different from that of the first embodiment. The configuration of the circuit unit 170 will be described later with reference to FIG. In the laser radar device 100 of the second embodiment, the portions not shown in FIG. 8 are the same as those of the first embodiment.

  The photodiodes 120H and 120L are arranged at different positions in order to receive the reflected light L1 divided by the beam splitter 135. The photodiode 120H is disposed at a position for receiving the reflected light L1 transmitted through the beam splitter 135. On the other hand, the photodiode 120L is arranged at a position for receiving the reflected light L1 reflected by the beam splitter 135.

  The light receiving sensitivity of the photodiodes 120H and 120L can be the same light receiving sensitivity as that of the photodiode 20 of the first embodiment. However, one or both of the photodiodes 120H and 120L may have a light receiving sensitivity different from that of the photodiode 20 of the first embodiment.

  As for the light receiving sensitivity of the photodiode 120H, the detection performance level determined by the light receiving sensitivity, the amplification factor of the amplifier 172H shown in FIG. Further, the light reception sensitivity of the photodiode 120L may be a low detection performance level determined by the light reception sensitivity, the amplification factor of the amplifier 172L shown in FIG. 9, and the division ratio of the beam splitter 135.

  The beam splitter 135 is disposed at a position where the reflected light L1 reflected by the reflecting surface 41 of the perforated mirror 40 is incident, reflects a part of the reflected light L1, and transmits the rest. Thereby, the beam splitter 135 divides the reflected light L1 reflected by the reflecting surface 41 of the perforated mirror 40 into the direction in which the photodiode 120H is located and the direction in which the photodiode 120L is located. Although the beam splitter 135 shown in FIG. 8 is a plate type, beam splitters having various structures such as a cube type can be used.

  Various division ratios of the beam splitter 135 can be set. In the present embodiment, the photodiode 120H can detect the detection target object at a high detection performance level, and the photodiode 120L detects the detection target object at a low detection performance level. Thus, the reflected light L1 is divided. For example, 80% of the reflected light L1 is transmitted and guided to the photodiode 120H, and 20% is reflected and guided to the photodiode 120L.

  Of course, the above numerical values are examples. The ratio between the light transmitted through the beam splitter 135 and the light reflected is adjusted so that the photodiode 120H functions as a photodiode for a high detection performance level and the photodiode 120L functions as a photodiode for a low detection performance level. It only has to be. An electric signal indicating the intensity of the reflected light L1 detected by each of the photodiodes 120H and 120L is supplied to the circuit unit 170.

  The circuit unit 170 has the configuration shown in FIG. In the configuration shown in FIG. 9, the difference from the circuit unit 70 of the first embodiment is that one amplifier 72 is provided in the first embodiment, whereas the circuit unit 170 of the second embodiment has two This is the point that the amplifiers 172H and 172L are provided, and the processing of the control unit 180.

  The amplifier 172H is connected to the photodiode 120H, amplifies the electrical signal output from the photodiode 120H, and outputs the amplified signal to the control unit 180. The amplifier 172L is connected to the photodiode 120L, amplifies the electrical signal output from the photodiode 120L, and outputs the amplified signal to the control unit 180. The amplification factor of the amplifier 172H is set to an amplification factor that allows measurement at a high detection performance level by the photodiode 120H. On the other hand, the amplification factor of the amplifier 172L is set to an amplification factor that allows measurement at a low detection performance level by the photodiode 120L.

  The hardware configuration of the control unit 180 is the same as that of the control unit 80 of the first embodiment, and includes circuits such as a CPU, ROM, RAM, ASIC, CPLD, and comparator. Similar to the control unit 80 of the first embodiment, the control unit 180 outputs a light emission command to the LD drive circuit 71 and outputs a motor drive signal to the motor drive circuit 73.

  Further, the control unit 180 also functions as each unit shown in FIG. That is, the control unit 180 also functions as a measurement processing unit 182, a low detection performance object determination unit 85, a high detection performance object determination unit 86, and a distance measurement unit 87.

  The measurement processing unit 182 includes a low detection performance measurement unit 183 and a high detection performance measurement unit 184. The low detection performance measurement unit 183 executes low detection performance measurement processing. As described in the first embodiment, the low detection performance measurement process is a process of receiving the reflected light L1 by scanning the irradiation light L0 in the monitoring area with the measurement unit 4 having the low detection performance level. In the second embodiment, the measurement unit 4 is set to a low detection performance level by using the reflected light L1 received by the photodiode 120L.

  Then, as in the first embodiment, the signal intensity of the reflected light L1 input from the amplifier 172L is compared with the object detection threshold. As a result of comparison, the time when the signal intensity of the reflected light L1 exceeds the object detection threshold and the time when the signal intensity of the reflected light L1 falls below the object detection threshold are stored in the storage unit 74 in association with the irradiation direction of the irradiation light L0. To do. Note that the object detection threshold may be a value that can be measured at a low detection performance level, and can be the same value as the object detection threshold of the first embodiment, for example.

  The high detection performance measurement unit 184 executes high detection performance measurement processing. The high detection performance measurement process is a process in which the measurement unit 4 having a high detection performance level scans the monitoring area with the irradiation light L0 and receives the reflected light L1. In the second embodiment, the measurement unit 4 is set to a high detection performance level by using the reflected light L1 received by the photodiode 120H.

  Then, the signal intensity of the reflected light L1 input from the amplifier 172H is compared with the object detection threshold value. As a result of comparison, the time when the signal intensity of the reflected light L1 exceeds the object detection threshold and the time when the signal intensity of the reflected light L1 falls below the object detection threshold are stored in the storage unit 74 in association with the irradiation direction of the irradiation light L0. To do. The object detection threshold only needs to be a value that can be measured at a high detection performance level, and can be set to the same value as the object detection threshold of the first embodiment, for example.

  In the second embodiment, the low detection performance measurement process by the low detection performance measurement unit 183 and the high detection performance measurement process by the high detection performance measurement unit 184 are both performed by one scan of the irradiation light L0. That is, the scanning of the irradiation light L0 in the high detection performance measurement process and the scanning of the irradiation light L0 in the low detection performance measurement process are the same scanning. Therefore, in the second embodiment, the output intensity of the laser diode 10 at the high detection performance level and the low detection performance level is the same.

  After the low detection performance measurement process by the low detection performance measurement unit 183 and the high detection performance measurement process by the high detection performance measurement unit 184, the low detection performance object determination unit 85 is similar to the first embodiment. The storage unit 74 stores the direction determined that the object exists at the low detection performance level and the direction determined that the object does not exist. Then, the high detection performance object determination unit 86 determines whether or not the object exists in a direction in which the low detection performance object determination unit 85 has not determined that the object exists.

  As described above, in the second embodiment described above, the beam splitter 135 that includes the two photodiodes 120H and 120L and divides the reflected light L1 into the direction incident on the photodiode 120H and the direction incident on the photodiode 120L is provided. Prepare. Thereby, the photodiode 120H and the photodiode 120L can receive the reflected light L1 generated from the same irradiation light L0.

  The split ratio of the beam splitter 135 is set so that the photodiode 120H functions as a photodiode for a high detection performance level and the photodiode 120L functions as a photodiode for a low detection performance level.

  Based on this configuration, the low detection performance measurement unit 183 and the high detection performance measurement unit 184 perform low detection performance measurement processing and high detection performance measurement processing, respectively, by scanning with the same irradiation light L0. Therefore, the laser radar device 100 according to the second embodiment has a high detection performance object compared to the case where the low detection performance measurement processing and the high detection performance measurement processing are alternately performed as in the laser radar device 1 according to the first embodiment. The period in which the determination unit 86 performs the determination, that is, the object detection period can be shortened.

  Unlike the first embodiment, it is not necessary to change the output intensity of the laser diode 10 in order to obtain a high-performance detection level and a low detection performance level, and it is also necessary to switch the light receiving sensitivity of the photodiode 120H and the photodiode 120L. There is no. Therefore, there is an advantage that it is not necessary to provide a configuration for changing the intensity of the irradiation light L0 or a configuration for changing the light receiving sensitivity.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, The following modification is also contained in the technical scope of this invention, Furthermore, the summary other than the following is also included. Various modifications can be made without departing from the scope.

<Modification 1>
For example, in the above-described embodiment, the low detection performance level and the high detection performance level are set without changing the light receiving sensitivity while changing the intensity of the irradiation light L0. However, the low detection performance level and the high detection performance level may be set by changing only the light reception sensitivity, or the low detection performance level and the high detection performance level may be set by changing both the intensity of the irradiation light L0 and the light reception sensitivity. May be set.

<Modification 2>
The laser radar device 1 of the above-described embodiment includes the perforated mirror 40 and is configured to irradiate the rotating mirror 50 with the irradiation light L0 from the through hole 42 of the perforated mirror 40, but is not limited thereto. . A configuration in which the positions of the laser diode 10 and the photodiode 20 are interchanged and the irradiation light L0 is reflected by a reflecting plate to irradiate the rotary mirror 50 with the irradiation light L0. Further, the present invention is not limited to the coaxial system in which the light projecting unit and the light receiving unit commonly use the rotating mirror 50, but the present invention can also be applied to other-axis laser radar devices that use rotating mirrors having different light projecting units and light receiving units. .

<Modification 3>
In the above-described embodiment, the low detection performance measurement unit 83 and the high detection performance measurement unit 84 indicate that the signal intensity of the reflected light L1 exceeds the object detection threshold, and the signal intensity of the reflected light L1 falls below the object detection threshold. The time was stored in the storage unit 74 in association with the irradiation direction of the irradiation light L0. However, instead of this, the waveform of the reflected light L <b> 1 may be stored in the storage unit 74.

<Modification 4>
In the above-described embodiment, even in the high detection performance measurement process, the irradiation light L0 is applied to the same angle range as in the low detection performance measurement process. However, instead of this, the low detection performance object determination unit 85 may irradiate the irradiation light L0 only to the angle determined that the object does not exist.

<Modification 5>
In the second embodiment, the photodiode 120H for the high detection performance level is arranged at a position for receiving the reflected light L1 transmitted through the beam splitter 135, and the beam splitter 135 reflects the photodiode 120L for the low detection performance level. The reflected light L1 is disposed at a position for receiving the reflected light L1. However, on the contrary, the photodiode 120H for the high detection performance level is arranged at a position for receiving the reflected light L1 reflected by the beam splitter 135, and the photodiode 120L for the low detection performance level is placed in the beam splitter 135. You may arrange | position in the position which receives the reflected light L1 which permeate | transmitted.

1: Laser radar device 2: Housing 3: Housing window 4: Measuring unit 10: Laser diode 20: Photo diode 30: Collimating lens 40: Perforated mirror 41: Reflecting surface 42: Through hole 50: Rotating mirror 51: Concave mirror 60: Motor 61: Rotating shaft 62: Rotational angle position sensor 70: Circuit unit 71: LD drive circuit 72: Amplifier 73: Motor drive circuit 74: Storage unit 80: Control unit 81: Detection performance level setting unit 82: Measurement processing unit 83: Low detection performance measurement unit 84: High detection performance measurement unit 85: Low detection performance object determination unit 86: High detection performance object determination unit 87: Distance measurement unit 90: Car 92: Pedestrian 94: Fog 96: Pedestrian 100 : Laser radar device 1 4: Measurement unit 120H, 120L: photodiode 170: circuit unit 172h, 172L: amplifier 180: Control unit 182: Measurement unit 183: low detection performance measurement unit 184: high detection performance measuring unit

Claims (5)

A light projecting unit (10) for generating and projecting laser light;
A scanning unit (50, 60) for irradiating the laser beam projected by the light projecting unit to the outside of the apparatus while changing an irradiation direction;
A light receiving unit (20, 120H, 120L) that receives reflected light generated by the laser beam irradiated to the outside of the device by the scanning unit reflected from the outside of the device;
A laser radar device (1, 100) having a measuring unit (4, 104) comprising:
The measurement unit has a low reflectivity and a detection performance level indicating the ease of detection of an object determined by the intensity of the laser light projected by the light projecting unit and the light receiving sensitivity by which the light receiving unit receives the reflected light. A high detection performance level that can be detected when a low-reflection detection target object that is a preset detection target object is at a reference angle with respect to the laser radar device at a reference distance, and at the reference distance Detecting the detection target object at two types of detection performance levels of a low detection performance level that does not detect the low reflection detection target object at the reference angle with respect to the laser radar device;
The measurement unit having the low detection performance level performs low detection performance measurement processing in which the scanning unit changes the irradiation direction and irradiates the laser beam outside the apparatus, and the light receiving unit receives the reflected light. A low detection performance measurement unit (83, 183) to be executed;
Based on the reflected light received by the light receiving unit by the low detection performance measurement unit executing the low detection performance measurement process, an object exists in a direction in which the laser light is irradiated by the low detection performance measurement process. A low detection performance object determination unit (85) for determining whether or not,
In the measurement unit having the high detection performance level, the low detection performance object determination unit irradiates the laser beam by the scanning unit with respect to a direction including at least a direction in which the object is not determined to exist. A high detection performance measurement unit (84, 184) for performing a high detection performance measurement process for receiving the reflected light by the light receiving unit;
The waveform of the reflected light received by the light receiving unit by the high detection performance measurement unit executing the high detection performance measurement process in a direction in which the low detection performance object determination unit has not determined that the object exists. A laser radar device comprising: a high detection performance object determination unit (86) that determines that the object is present based on a width that is shorter than a fog determination width threshold. In claim 1,
A detection performance level setting unit (81) for setting the high detection performance level and the low detection performance level by changing at least one of the intensity of the laser beam and the light receiving sensitivity;
The low detection performance measurement unit (83) executes the low detection performance measurement process by setting the detection performance level of the measurement unit to the low detection performance level by the detection performance level setting unit,
The high detection performance measurement unit (84) sets the detection performance level of the measurement unit to the high detection performance level by the detection performance level setting unit and executes the high detection performance measurement process. Laser radar device. In claim 2,
The detection performance level setting unit changes the intensity of the laser light projected by the light projecting unit, while the light receiving sensitivity at which the light receiving unit receives the reflected light is not changed, and the low detection performance level and the A laser radar device characterized by setting a high detection performance level. In claim 1,
The light receiving unit includes a first light receiving unit (120H) and a second light receiving unit (120L) that are arranged at different positions and receive the reflected light,
In the measuring unit (104), the first light receiving unit detects the detection target object at the high detection performance level, and the second light receiving unit detects the detection target object at the low detection performance level. A laser radar device comprising a beam splitter (135) for dividing the reflected light at a division ratio. In any one of Claims 1-4,
The high detection performance object determination unit executes the high detection performance measurement process by the high detection performance measurement unit for a single direction in which the low detection performance object determination unit has not determined that the object exists. If the section of the reflected light detected by the light receiving unit exceeds two object determination thresholds, it is determined that the object exists without comparing the waveform width of the reflected light with the fog determination width threshold. A laser radar device characterized by that.

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