JPWO2018101293A1 - Measuring device, setting device, setting method, correction method, and program - Google Patents

Abstract

The measurement device (200) includes a measurement unit (202) and a control unit (204). The measurement unit (202) scans an object by irradiating an electromagnetic wave and receiving a reflected wave of the irradiated electromagnetic wave. The control unit (204) controls scanning of the object by the measurement unit (202). Specifically, in the control unit (204), the number of times that the intensity of the electromagnetic wave received by the measurement unit (202) is equal to or higher than a predetermined level is less than the predetermined number of times for one scan by the measurement unit (202). As described above, the irradiation of electromagnetic waves by the measurement unit (202) is controlled.

Description

  The present invention relates to a technique for performing measurement by irradiating electromagnetic waves.

  A technique for detecting an obstacle by irradiating an electromagnetic wave and scanning an object has been developed. Patent Document 1 discloses a technique for detecting an obstacle or the like by irradiating a laser beam and scanning within a target area in an apparatus installed in an automobile or the like. Further, Patent Document 1 discloses a technique for changing the central axis in the horizontal direction of the scan region in accordance with the steering angle of the automobile.

JP 2006-258604 A

  Inside the measuring device, electromagnetic waves emitted from the light source pass through the optical system. At this time, stray light may be generated when a part of the electromagnetic wave is reflected by the optical system. Such stray light is a factor that lowers the accuracy of measurement by the measurement device.

  This invention is made | formed in view of the above-mentioned subject, and it aims at providing the technique which suppresses generation | occurrence | production of the stray light in a measuring device.

The invention described in claim 1 is an invention of a measuring device. The measurement apparatus includes (1) a measurement unit that performs scanning by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is reflected to the outside, and is reflected by the reflector; And a control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit.
The number of times that the measurement unit irradiates the electromagnetic wave received with a strength of a predetermined value or more in one scan by the measurement unit is less than the predetermined number.

The invention according to claim 2 is an invention of a setting device for setting a measuring device.
The measurement device uses a measurement unit that performs scanning by receiving the electromagnetic wave irradiated from the light source through the optical system and reflected by a reflector, and a driving signal. And a control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit.
The setting device (1) operates the measurement device in which a predetermined signal is set as the drive signal, acquires a measurement result by the measurement device, and (2) the strength of a predetermined value or more by the measurement device. By changing the irradiation timing indicated by the predetermined drive signal with respect to the electromagnetic wave received in step 1, the number of irradiation times of the electromagnetic wave received with a strength of a predetermined value or more in one scan by the measurement unit is made less than the predetermined number of times. .

The invention according to claim 5 is an invention of a setting method of a measuring device.
The measurement device uses a measurement unit that performs scanning by receiving the electromagnetic wave irradiated from the light source through the optical system and reflected by a reflector, and a driving signal. And a control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit.
The setting method includes the steps of (1) operating the measurement device in which a predetermined signal is set as the drive signal to obtain a measurement result by the measurement device, and (2) a predetermined value or more by the measurement device. By changing the irradiation timing indicated by the predetermined drive signal with respect to the electromagnetic wave received with intensity, the number of times of irradiation of the electromagnetic wave received with an intensity of a predetermined value or more in one scan by the measurement unit is less than the predetermined number. And a step of.

  The invention according to claim 6 is an invention of a program for causing a computer to execute each step of the setting method according to claim 5.

The invention according to claim 7 is an invention of a measuring device.
The measurement apparatus includes (1) a measurement unit that performs scanning by receiving the electromagnetic wave irradiated from the light source through the optical system and reflected by the reflector, and (2) driving. A control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit using a signal; and (3) a correction unit that corrects the drive signal.
The correction unit changes the irradiation timing indicated by the drive signal for the electromagnetic wave received by the measurement unit with a strength of a predetermined value or more, so that the correction unit has a strength of a predetermined value or more in one scan by the measurement unit. The number of irradiation times of the received electromagnetic wave is made less than a predetermined number.

The invention described in claim 10 is an invention of a correction method executed by the measuring apparatus.
The measurement device uses a measurement unit that performs scanning by receiving the electromagnetic wave irradiated from the light source through the optical system and reflected by a reflector, and a driving signal. A control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit.
In the correction method, by changing the irradiation timing indicated by the drive signal for the electromagnetic wave received by the measurement device with an intensity greater than or equal to a predetermined value, the intensity is greater than or equal to a predetermined value in one scan by the measurement unit. A step of setting the number of irradiation times of the received electromagnetic wave to less than a predetermined number.

  The invention according to claim 11 is an invention of a program for causing a computer to execute each step of the correction method according to claim 10.

The invention described in claim 12 is an invention of a measuring device.
The measurement device includes: (1) a measurement unit including a light source, and a reception unit that receives the electromagnetic wave that is irradiated from the light source through the optical system and is reflected to the outside and reflected by the reflector. (2) a control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit.
The control unit changes the irradiation timing of the measurement unit when the reception unit receives reflected light, which is reflected from the optical system by the electromagnetic wave irradiated from the light source, with a predetermined intensity or more.

The invention described in claim 14 is an invention of a measuring device.
The measurement device includes: (1) a measurement unit including a light source, and a reception unit that receives the electromagnetic wave that is irradiated from the light source through the optical system and is reflected to the outside and reflected by the reflector. (2) When the receiving unit receives the reflected light reflected by the optical system from the light source at a predetermined intensity or more, executes a process of changing the irradiation timing of the electromagnetic wave A control unit.
The control unit executes the process when it is determined that there is no object that reflects the electromagnetic wave in the vicinity of the measurement apparatus and in the direction in which the electromagnetic wave is irradiated.

  The above-described object and other objects, features, and advantages will become more apparent from the preferred embodiments described below and the accompanying drawings.

1 is a block diagram illustrating a measurement device according to a first embodiment. It is a figure which illustrates the mode of the scanning by a measurement part. It is a figure which illustrates the intensity of the stray light received by a receiver. It is a figure which illustrates the hardware constitutions of a control part. It is a figure which illustrates the hardware constitutions of a measurement part. It is a figure which illustrates the hardware constitutions of the measurement part which irradiates light. It is a 1st flowchart which illustrates the flow of the procedure which produces | generates a light source drive signal. It is a figure which illustrates a default signal. It is a figure for demonstrating the method to identify the irradiation timing of the electromagnetic waves which are generation sources of stray light. It is a figure which compares the light source drive signal set to a control part with a default signal. It is a 2nd flowchart which illustrates the flow of the procedure which produces | generates a light source drive signal. It is a figure which illustrates the computer for implement | achieving a setting apparatus. It is a figure which illustrates the measuring device installed in the mobile body. 6 is a block diagram illustrating a measurement device according to a second embodiment. FIG. It is a 1st flowchart which illustrates the flow of the procedure which produces | generates a light source drive signal. It is a 2nd flowchart which illustrates the flow of the procedure which produces | generates a light source drive signal. FIG. 16 is a block diagram illustrating a measurement apparatus 200 having a function of specifying a place suitable for executing the operation shown in the flowchart of FIG. 15 and executing the operation at the place.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a block diagram illustrating a measurement apparatus 200 according to the first embodiment. In FIG. 1, each block represents a functional unit configuration, not a hardware unit configuration. The hardware configuration of the measuring device 200 will be described later with reference to FIGS.

  The measurement device 200 includes a measurement unit 202 and a control unit 204. The measurement unit 202 scans an object by irradiating an electromagnetic wave and receiving a reflected wave of the irradiated electromagnetic wave. The control unit 204 controls the scanning of the object by the measurement unit 202. Further, the control unit 204 measures the time from when the electromagnetic wave is irradiated by the measuring unit 202 until the reflected wave of the electromagnetic wave is received.

  Here, the measurement unit 202 scans the object while changing the irradiation direction of the electromagnetic wave in two dimensions, the height direction and the horizontal direction. The height direction means a substantially vertical direction. Further, the horizontal direction means a substantially horizontal direction.

  FIG. 2 is a diagram illustrating a state of scanning by the measurement unit 202. In this example, raster scanning is performed within the scanning range 224. In this raster scan, the main scanning direction is the horizontal direction, and the sub-scanning direction is the height direction.

  A trajectory 1 represents a trajectory of scanning by the measurement unit 202. The irradiation direction of the electromagnetic wave by the irradiator 10 changes with time along the locus 1. Each x mark represents a position through which the electromagnetic wave irradiated from the irradiator 10 passes. That is, the electromagnetic wave is irradiated from the irradiator 10 at the timing of passing through each x mark.

  The measurement unit 202 includes the irradiator 10, the optical system 20, and the receiver 50. The irradiator 10 irradiates electromagnetic waves while changing the irradiation direction. The optical system 20 converges the electromagnetic wave emitted from the irradiator 10. The receiver 50 receives electromagnetic waves.

  Here, the receiver 50 is provided to receive the electromagnetic wave irradiated from the measuring unit 202 and reflected by an object (hereinafter, reflected wave). However, the electromagnetic wave received by the receiver 50 may include other than the reflected wave of the electromagnetic wave irradiated from the measurement unit 202. For example, the electromagnetic wave received by the receiver 50 may include an electromagnetic wave irradiated from the irradiator 10 reflected by the surface of the optical system 20 (so-called stray light).

  The intensity of stray light received by the receiver 50 differs depending on the direction in which the electromagnetic wave is emitted from the irradiator 10. This is because the angle at which the electromagnetic wave enters the optical system 20 and the position at which the electromagnetic wave enters the optical system 20 differ depending on the direction in which the electromagnetic wave is irradiated from the irradiator 10.

  FIG. 3 is a diagram illustrating the intensity of stray light received by the receiver 50. The irradiator 10 performs raster scanning with the horizontal direction as the main scanning direction (see FIG. 2). The irradiator 10 emits electromagnetic waves at a predetermined interval (see graph 60). Furthermore, it is assumed that no object exists around the measuring device 200.

  The graph 60 represents the timing at which the electromagnetic wave is irradiated from the irradiator 10 as a pulse signal. Specifically, the electromagnetic wave is emitted from the irradiator 10 at the timing when the signal value changes from 0 to 1 in the graph 60. A graph 62 represents the intensity of the electromagnetic wave received by the receiver 50.

  Since there is no object around the measuring apparatus 200, the electromagnetic wave reflected by the object is hardly received by the receiver 50. Therefore, in the graph 62, the intensity of the electromagnetic wave received by the receiver 50 is almost zero at most points in time.

  However, at some points in time, the intensity of the electromagnetic wave received by the receiver 50 has increased. This is because stray light is generated by electromagnetic waves irradiated at a specific timing (electromagnetic waves irradiated in a specific direction), and the stray light is received by the receiver 50.

  For example, stray light is received by the receiver 50 at time t1. It can be said that this stray light is generated by the electromagnetic wave irradiated from the irradiator 10 at the time point t2. Because the distance between the irradiator 10 and the optical system 20 is short, it is considered that the time difference between the timing when the irradiator 10 causing stray light is irradiated and the timing when the stray light is received by the receiver 50 is short. Because.

  When stray light is received by the receiver 50 in this way, the measurement result of the measuring device 200 becomes inaccurate. For example, when the measuring apparatus 200 receives an electromagnetic wave having a strength equal to or greater than a predetermined value, it is determined that the reflected wave reflected by the object has been received. In this case, when the measuring apparatus 200 receives stray light, it erroneously determines that the reflected wave reflected by the object has been received.

  Therefore, in the measurement apparatus 200 of this embodiment, the timing at which the electromagnetic wave is emitted from the irradiator 10 is controlled so that the electromagnetic wave is emitted from the irradiator 10 while avoiding the timing at which stray light is generated. Specifically, “at what timing the electromagnetic wave is generated when stray light is generated” is grasped in advance, and the electromagnetic wave is irradiated while avoiding the timing. In other words, “in which direction the electromagnetic wave is generated when stray light is generated” is grasped in advance, and the electromagnetic wave is not irradiated in that direction.

  More specifically, the control unit 204 of the present embodiment determines that the number of times the intensity of the electromagnetic wave received by the measurement unit 202 is equal to or higher than a predetermined level is one scan (for example, one raster scan) by the measurement unit 202. ), The irradiation of the electromagnetic wave by the measuring unit 202 is controlled so as to be less than a predetermined number of times.

  By doing so, according to the measuring apparatus 200 of the present embodiment, stray light can be prevented from being generated by the electromagnetic waves irradiated from the irradiator 10. Therefore, the accuracy of measurement by the measurement apparatus 200 is improved.

  Hereinafter, the measuring apparatus 200 of the present embodiment will be described in more detail.

<Example of Hardware Configuration of Measuring Device 200>

  Each functional component of the measuring apparatus 200 may be realized by hardware (eg, a hard-wired electronic circuit) that implements each functional component, or a combination of hardware and software (eg, electronic A combination of a circuit and a program for controlling the circuit may be realized. Hereinafter, the case where each functional component of the measuring device 200 is realized by a combination of hardware and software will be further described.

<< Example of Hardware Configuration of Control Unit 204 >>

  FIG. 4 is a diagram illustrating a hardware configuration of the control unit 204. The integrated circuit 100 is an integrated circuit that implements the control unit 204. For example, the integrated circuit 100 is an SoC (System On Chip).

  The integrated circuit 100 includes a bus 102, a processor 104, a memory 106, a storage device 108, an input / output interface 110, and a network interface 112. The bus 102 is a data transmission path through which the processor 104, the memory 106, the storage device 108, the input / output interface 110, and the network interface 112 transmit / receive data to / from each other. However, the method of connecting the processors 104 and the like is not limited to bus connection. The processor 104 is an arithmetic processing device realized using a microprocessor or the like. The memory 106 is a main storage device realized using a RAM (Random Access Memory) or the like. The storage device 108 is an auxiliary storage device realized using a ROM (Read Only Memory), a flash memory, or the like.

  The input / output interface 110 is an interface for connecting the integrated circuit 100 to peripheral devices. In FIG. 4, an irradiator drive circuit 30 is connected to the input / output interface 110. The irradiator drive circuit 30 will be described later.

  The network interface 112 is an interface for connecting the integrated circuit 100 to a communication network. This communication network is, for example, a CAN (Controller Area Network) communication network. Note that a method of connecting the network interface 112 to the communication network may be a wireless connection or a wired connection.

  The storage device 108 stores a program module for realizing the function of the control unit 204. The processor 104 reads out the program module to the memory 106 and executes it, thereby realizing the function of the control unit 204.

  The hardware configuration of the integrated circuit 100 is not limited to the configuration shown in FIG. For example, the program module may be stored in the memory 106. In this case, the integrated circuit 100 may not include the storage device 108.

<< Hardware Configuration Example of Measuring Unit 202 >>

  FIG. 5 is a diagram illustrating a hardware configuration of the measurement unit 202. The measurement unit 202 includes an irradiator 10, an optical system 20, an irradiator drive circuit 30, and a receiver 50. The irradiator 10 irradiates electromagnetic waves used for scanning an object. Here, the irradiator 10 has a configuration in which the irradiation direction is variable, and can irradiate electromagnetic waves in various directions. The irradiator drive circuit 30 is a circuit that drives the irradiator 10. More specifically, the drive circuit 30 of the irradiator includes a circuit that drives a mechanism (for example, a light source) that radiates electromagnetic waves, and a circuit that drives a mechanism (for example, a mirror) that changes the irradiation direction of the irradiator 10. The optical system 20 converges the electromagnetic wave emitted from the irradiator 10. The receiver 50 receives the reflected wave of the electromagnetic wave irradiated to the outside of the measuring device 200.

  The control unit 204 detects that the reflected wave is received by the receiver 50. For example, the receiver 50 is configured to transmit a predetermined signal to the control unit 204 in response to receiving the reflected wave. The control unit 204 detects that the reflected wave has been received by the receiver 50 by receiving the predetermined signal.

  The control unit 204 measures the elapsed time from when the electromagnetic wave is irradiated from the irradiator 10 until the reflected wave of the electromagnetic wave is received by the receiver 50, and the measurement time is used as the electromagnetic wave irradiation direction (electromagnetic wave irradiation timing). And stored in a storage device (for example, the storage device 108). This elapsed time is represented by, for example, a value obtained by multiplying the number of clock signals counted from when the electromagnetic wave is irradiated from the irradiator 10 to when the reflected wave of the electromagnetic wave is received by the clock period. For example, this elapsed time may be represented by the number of clock signals counted. Based on this elapsed time, for example, the distance between the scanned object and the measuring apparatus 200 can be calculated.

  The electromagnetic wave irradiated by the irradiator 10 may be a light such as a laser beam or a radio wave such as a millimeter wave. Hereinafter, the hardware configuration of the measurement unit 202 when the irradiator 10 emits light will be exemplified. A similar configuration can be adopted for the measurement unit 202 when the irradiator 10 emits electromagnetic waves.

  FIG. 6 is a diagram illustrating a hardware configuration of the measurement unit 202 that emits light. The projector 12 and the projector driving circuit 32 in FIG. 6 are examples of the irradiator 10 and the irradiator driving circuit 30 in FIG. 5, respectively. The projector 12 includes a light source 14 and a movable reflecting portion 16. The projector drive circuit 32 includes a light source drive circuit 34 and a movable reflection unit drive circuit 36.

  The light source 14 is an arbitrary light source that emits light. The light source drive circuit 34 is a circuit that drives the light source 14 by controlling the supply of power to the light source 14. The light irradiated by the light source 14 is, for example, laser light. In this case, for example, the light source 14 is a semiconductor laser that emits laser light.

  The movable reflector 16 reflects the light emitted from the light source 14. The light reflected by the movable reflecting portion 16 is irradiated to the outside of the measuring apparatus 200 after passing through the lens 22. The lens 22 is an example of the optical system 20 in FIG.

  The movable reflection unit drive circuit 36 is a circuit for driving the movable reflection unit 16. For example, the movable reflecting portion 16 has one mirror configured to be rotatable in at least two directions of the height direction and the horizontal direction. This mirror is, for example, a MEMS (Micro Electro Mechanical System) mirror.

  The configuration of the movable reflecting portion 16 is not limited to the configuration shown in FIG. For example, the movable reflecting portion 16 may be composed of two mirrors whose rotation axes intersect with each other.

  The operations of the light source drive circuit 34 and the movable reflector drive circuit 36 are controlled by the control unit 204. Specifically, the control unit 204 transmits a drive signal for instructing driving of the light source 14 to the drive circuit 34 of the light source. This drive signal is read from the storage device 108, for example. The light source drive circuit 34 drives the light source 14 based on the received drive signal. For example, when the drive signal is a pulse signal composed of binary values of high and low, the light source drive circuit 34 drives the light source 14 at a timing when the pulse signal changes from low to high (irradiates light from the light source 14). )

  Similarly, the control unit 204 transmits a drive signal instructing driving of the movable reflection unit 16 to the drive circuit 36 of the movable reflection unit. This drive signal is also read from the storage device 108, for example. The drive circuit 36 for the movable reflector controls the attitude of the movable reflector 16 based on this drive signal. By this control, the light irradiation direction is controlled. For example, the light irradiation direction is controlled as shown by the locus 1 in FIG.

  Further, the measuring unit 202 includes a light receiver 52. The light receiver 52 is an example of the receiver 50 in FIG. For example, the light receiver 52 is configured using an APD (Avalanche Photodiode).

  Note that the configuration of the measurement unit 202 is not limited to the configuration illustrated in FIGS. 5 and 6. For example, in FIG. 6, the measurement unit 202 is configured to irradiate light in various directions by reflecting the light emitted from the light source 14 by the movable reflection unit 16. However, the configuration for irradiating light in various directions is not limited to the configuration shown in FIG. For example, the light source 14 itself may have a mechanism that rotates in the height direction and the horizontal direction. In this case, the measurement unit 202 can irradiate light in various directions by controlling the posture of the light source 14. In this case, the measurement unit 202 may not include the movable reflection unit 16 and the drive circuit 36 for the movable reflection unit. Further, in this case, the light source drive circuit 34 includes a drive circuit that irradiates light to the light source 14 and a drive circuit that changes the posture of the light source 14.

  Note that the hardware that implements the control unit 204 (see FIG. 4) and the hardware that implements the measurement unit 202 (see FIG. 5 and FIG. 6) may be packaged in the same housing, or separate housings. It may be packaged in the body.

  In the following description, a case where the hardware configuration of the measurement unit 202 is represented in FIG. 6 will be described unless otherwise specified.

<About the determination method of the timing which the measurement part 202 irradiates electromagnetic waves>

  As described above, in the measurement apparatus 200 according to the present embodiment, the generation of stray light is suppressed by appropriately setting the timing at which the electromagnetic wave is emitted from the measurement unit 202 in advance. This setting is performed, for example, before the operation of the measurement apparatus 200 is started (for example, before the measurement apparatus 200 is shipped).

  The above setting is realized by appropriately generating a drive signal (hereinafter, a light source drive signal) to be transmitted to the light source drive circuit 34. The generated light source drive signal is stored in the storage device 108, for example. The control unit 204 reads out the light source driving signal appropriately generated in advance as described above from the storage device 108 and transmits it to the light source driving circuit 34. By carrying out like this, electromagnetic waves are irradiated from the irradiator 10 with the appropriate timing which a stray light does not generate | occur | produce.

  Hereinafter, a method of generating the light source driving signal will be specifically described. In the following description, it is assumed that the measurement unit 202 performs raster scanning. The light source drive signal transmitted to the light source drive circuit 34 is the pulse signal described above.

  Further, in the following description, the light source drive signal is generated by a computer. A computer that generates a light source drive signal is referred to as a setting device 300. The setting device 300 is realized using an arbitrary computer such as a PC (Personal Computer), a server device, or a mobile terminal. The light source drive signal may be generated by manually performing a process similar to a series of processes executed by the setting device 300.

  The generation of the light source drive signal is performed by operating the measurement apparatus 200 in a test environment. It is preferable that the test environment is an environment where the reflected wave of the electromagnetic wave irradiated from the measuring device 200 is not received by the receiver 50 or an environment where the intensity of the received reflected wave is negligible.

<< Example 1 of Procedure for Generating Light Source Driving Signal >>

  FIG. 7 is a first flowchart illustrating the flow of the procedure for generating the light source drive signal. The setting device 300 sets a default signal as a light source driving signal used by the control unit 204 to control the measurement unit 202 (S102). Specifically, the setting apparatus 300 stores a default signal in the storage device 108 included in the control unit 204.

  The default signal is an arbitrary drive signal that is defined in advance in order to perform initial setting on the control unit 204. For example, the default signal is defined such that a plurality of times of electromagnetic wave irradiation performed in one main scanning (scanning in one horizontal line in the trajectory 1) are performed at equal time intervals. Let the length of this time interval be p clocks (p is a positive integer). FIG. 8 is a diagram illustrating a default signal. Note that information defining the default signal (or the default signal itself) is stored in advance in a storage device included in the setting device 300.

  The setting device 300 causes the measurement device 200 to perform measurement (S104). Here, electromagnetic waves are emitted from the measurement unit 202 according to a default signal.

  The setting apparatus 300 acquires the measurement result obtained by the measurement apparatus 200, and specifies the irradiation timing of the electromagnetic wave that generated stray light (S106). Specifically, first, the setting device 300 specifies a time point when the receiver 50 receives an electromagnetic wave (stray light) having a strength greater than or equal to a predetermined value. And the setting apparatus 300 specifies the irradiation timing of the electromagnetic wave which is the generation source of the stray light received at that time.

  FIG. 9 is a diagram for explaining a method of specifying the irradiation timing of an electromagnetic wave that is a generation source of stray light. In FIG. 9, an electromagnetic wave (stray light) having a strength greater than or equal to a predetermined value is received at the time c1 clock. Therefore, the setting device 300 identifies the irradiation timing of the electromagnetic wave that is the source of this stray light.

  Here, p clock, which is the time interval between the irradiation timings of two consecutive electromagnetic waves, is the time interval between the time when the electromagnetic wave is irradiated from the irradiator 10 and the time when the stray light generated by the electromagnetic wave is received by the receiver 50. Than long enough. Therefore, it can be estimated that the irradiation timing of the electromagnetic wave that is the generation source of the stray light is the time c2 clock that is the latest irradiation timing among the irradiation timings before the time c1 when the stray light is received.

  Therefore, the setting device 300 specifies the c2 clock as the irradiation timing of the electromagnetic wave that is the source of stray light.

  When stray light is generated a plurality of times in one scan (a series of irradiation of electromagnetic waves represented by the locus 1), there are a plurality of “time points when the receiver 50 receives an electromagnetic wave having a predetermined value or more”. Exists. In this case, the setting device 300 specifies the irradiation timing of each of the plurality of electromagnetic waves that generated stray light from each of the plurality of time points.

  The setting apparatus 300 determines whether or not one or more irradiation timings of the electromagnetic wave that generated stray light have been specified in S106 (S108). If no irradiation timing of the electromagnetic wave causing the stray light is specified (S108: NO), the process of FIG. 7 ends. Therefore, the light source drive signal set in the control unit 204 remains the default signal. In this case, no stray light is generated even when the control unit 204 controls the measurement unit 202 with a default signal. Therefore, the control unit 204 controls the measurement unit 202 using the default signal even during operation.

  On the other hand, when one or more irradiation timings of electromagnetic waves that generate stray light are specified (S108: YES), the setting device 300 changes a part of the default signal to change the light source drive signal set in the control unit 204. Is generated (S110). Specifically, the setting device 300 generates a light source drive signal to be set in the control unit 204 by changing only the irradiation timing of the electromagnetic wave in which stray light is generated among the irradiation timings of the electromagnetic wave in the default signal. That is, the light source drive signal set in the control unit 204 is (1) the irradiation timing of the electromagnetic wave that generated stray light in the default signal is deviated by a predetermined clock k from the irradiation timing in the default signal. The electromagnetic wave irradiation timing coincides with the irradiation timing in the default signal.

  In the example of FIG. 7, if at least one irradiation timing of the electromagnetic wave that generated stray light is specified in S108, the default signal is changed. However, the setting device 300 is configured to change a part of the default signal when the irradiation timing of the electromagnetic wave that generated the stray light is specified in N (N) (N is an integer of 2 or more). Also good. In this case, if the irradiation timing of the electromagnetic wave that generated the stray light is less than N, it can be determined that the influence of the stray light on the measurement is small, and the default signal is not changed.

  In S110, instead of changing the irradiation timing of the electromagnetic wave in which the stray light is generated, the electromagnetic wave may not be irradiated in the irradiation timing of the electromagnetic wave in which the stray light is generated. By doing so, the influence of stray light can be reduced by simpler processing. In this method, although the number of times of irradiation of electromagnetic waves is reduced as compared with the case of using a default signal, if the irradiation timing of electromagnetic waves that generate stray light is not large, the influence on actual use is considered to be small.

  FIG. 10 is a diagram comparing the light source drive signal set in the control unit 204 and the default signal. The relationship between the strength of the received wave and the default signal in FIG. 10 is the same as in FIG. Therefore, when an electromagnetic wave is irradiated from the irradiator 10 according to the default signal, stray light is generated by the electromagnetic wave irradiated at the time point c2 clock. Therefore, the setting device 300 changes the irradiation timing of the electromagnetic wave irradiated at the time point c2 clock in the default signal to the time point c2 + k clock in the light source driving signal set in the control unit 204.

  Here, since the time interval of the irradiation timing of the electromagnetic wave is p clock, the predetermined clock k is determined to satisfy −p / 2 ≦ k ≦ p / 2. If p / 2 is not an integer, the lower limit of the k range is the smallest integer greater than -p / 2, and the upper limit of the k range is the largest integer less than p / 2.

  Then, the setting device 300 sets the light source drive signal generated in S110 as the light source drive signal used by the control unit 204 to control the measurement unit 202 (S112). Specifically, the setting apparatus 300 stores the light source drive signal generated in S110 in the storage device 108 included in the control unit 204.

<< Example 2 of Procedure for Generating Light Source Drive Signal >>

  In this example, the setting device 300 generates a light source driving signal to be set in the control unit 204 by shifting the irradiation timing of the electromagnetic wave in the default signal as a whole. For example, if the default signal is expressed as a function f (t), a signal obtained by shifting the default signal by k clocks as a whole is expressed by f (t-k).

  However, if a signal obtained by shifting the default signal as a whole is used as a light source drive signal, stray light may be newly generated by electromagnetic waves that did not generate stray light with the default signal. Therefore, the setting device 300 generates a light source drive signal by the following procedure, for example.

  FIG. 11 is a second flowchart illustrating the flow of the procedure for generating the light source drive signal. In this processing, the setting device 300 sets a light source driving signal that causes the number of irradiation timings of electromagnetic waves that generate stray light to be less than a predetermined value in the control unit 204. This predetermined value is assumed to be stored in advance in a storage device included in the setting device 300. Note that S102 and S106 in FIG. 11 are the same processes as S102 and S104 in FIG. 7, respectively. Therefore, the processing after S202 will be described below.

  The setting device 300 sets an initial value 1 to the variable i representing the shift amount (S202). S204 to S222 is a loop process A that is repeatedly executed while the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value. In S204, the setting apparatus 300 determines whether or not the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value. If the number of irradiation timings of electromagnetic waves that generate stray light is not equal to or greater than a predetermined value, the processing in FIG. 11 ends. On the other hand, if the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value, the process in FIG. 11 proceeds to S206.

  In S206, the setting apparatus 300 sets a signal obtained by shifting the default signal as a whole by + i clocks in the control unit 204 as a light source driving signal. The setting device 300 causes the measurement device 200 to perform measurement (S208). The setting apparatus 300 acquires the measurement result by the measurement apparatus 200, and specifies the irradiation timing of the electromagnetic wave that generated stray light (S210).

  The setting apparatus 300 determines whether or not the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value (S212). When the number of irradiation timings of electromagnetic waves that generate stray light is not equal to or greater than a predetermined value (S212: NO), the process of FIG. 11 ends. On the other hand, if the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value (S212: YES), the process of FIG. 11 proceeds to S214.

  In S214, the setting device 300 sets a signal obtained by shifting the default signal as a whole by -i clocks in the control unit 204 as a light source drive signal. The setting device 300 operates the measuring device 200 (S216). The setting apparatus 300 acquires the measurement result by the measurement apparatus 200, and specifies the irradiation timing of the electromagnetic wave that generated stray light (S218). The setting device 300 adds 1 to the shift amount i (S220).

  S222 is the end of loop processing A. Therefore, the processing in FIG. 11 proceeds to S204.

<Example of Hardware Configuration of Setting Device 300>

  Each functional component of the setting device 300 may be realized by hardware (eg, a hard-wired electronic circuit) that implements each functional component, or a combination of hardware and software (eg, electronic A combination of a circuit and a program for controlling the circuit may be realized. Hereinafter, a case where each functional component of the setting device 300 is realized by a combination of hardware and software will be further described.

  FIG. 12 is a diagram illustrating a computer 400 for realizing the setting device 300. The computer 400 is an arbitrary computer. For example, the computer 400 is a personal computer (PC), a server machine, a tablet terminal, or a smartphone. The computer 400 may be a dedicated computer designed to realize the setting device 300 or a general-purpose computer.

  The computer 400 includes a bus 402, a processor 404, a memory 406, a storage device 408, an input / output interface 410, and a network interface 112. The bus 402 is a data transmission path through which the processor 404, the memory 406, the storage device 408, the input / output interface 410, and the network interface 412 transmit / receive data to / from each other. However, the method of connecting the processors 404 and the like is not limited to bus connection. The processor 404 is an arithmetic device such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The memory 406 is a main storage device realized using a RAM (Random Access Memory) or the like. The storage device 408 is an auxiliary storage device implemented using a hard disk, an SSD (Solid State Drive), a memory card, a ROM (Read Only Memory), or the like. However, the storage device 408 may be configured by hardware similar to the hardware configuring the main storage device such as RAM.

  The input / output interface 410 is an interface for connecting the computer 400 and an input / output device. The network interface 412 is an interface for connecting the computer 400 to a communication network. This communication network is, for example, a LAN (Local Area Network) or a WAN (Wide Area Network). A method of connecting the network interface 412 to the communication network may be a wireless connection or a wired connection.

  For example, the computer 400 is connected to the measurement apparatus 200 via the input / output interface 410 or the network interface 412.

  The storage device 408 stores program modules that implement the functions of the setting device 300. The processor 404 reads out the program module to the memory 406 and executes it, thereby realizing a function corresponding to the program module.

<Installation example of measuring device 200>

  The measuring device 200 is installed in a moving body such as an automobile or a train. The measuring device 200 installed in the moving body is realized as a lidar (LIDAR: Light Detection and Ranging), for example.

  FIG. 13 is a diagram illustrating a measuring apparatus 200 installed on a moving body. In FIG. 13, the measuring device 200 is fixed to the upper part of the moving body 240. The measuring device 200 is connected to the control device 244. The control device 244 is a control device that controls the moving body 240. For example, the control device 244 is an ECU (Electronic Control Unit).

  Here, the control unit 204 may be realized as a part of the control device 244 that controls the moving body 240. In this case, a program module that realizes the above-described control unit 204 is stored in a storage device included in the control device 244.

  In addition, the place where the measuring apparatus 200 is installed is not limited to the upper part of the moving body 240. For example, the measuring device 200 may be installed inside the moving body 240 (for example, indoors). Moreover, the measuring device 200 may be installed on an object that does not move.

[Embodiment 2]

  FIG. 14 is a block diagram illustrating a measurement apparatus 200 according to the second embodiment. Except for the matters described below, the measurement device 200 of the second embodiment has the same function as the measurement device 200 of the first embodiment.

  The measurement apparatus 200 of Embodiment 2 suppresses the generation of stray light by dynamically changing the irradiation timing of electromagnetic waves during operation of the measurement apparatus 200. For this purpose, the measurement apparatus 200 according to the second embodiment includes a correction unit 206.

  The correction unit 206 detects the occurrence of stray light in the measurement apparatus 200 and changes the timing at which the irradiator 10 is irradiated with electromagnetic waves so as to suppress the influence of stray light. Specifically, the correction unit 206 changes the irradiation timing of the irradiator 10 when the receiver 50 receives an electromagnetic wave having a predetermined intensity or more. In other words, the correction unit 206 identifies the irradiation timing of the electromagnetic wave that generates stray light, and based on the identified irradiation timing, the light source driving signal set in the control unit 204 (the light source driving stored in the storage device 108) Signal).

  Here, as described in the flowchart of FIG. 7, when the operation of specifying the irradiation timing of the electromagnetic wave that is the generation source of stray light based on the reception intensity of the receiver (light receiver) is executed, the moving object 240 (or It is desirable to execute in a situation where there is no object (for example, a feature, a pedestrian, another vehicle, etc.) that reflects electromagnetic waves around the measuring device 200). For example, it is desirable that the measurement apparatus 200 be executed in a state where there is no object that reflects electromagnetic waves within a range where measurement is possible.

  Therefore, as described below, a location suitable for executing the operation shown in the flowchart of FIG. 15 may be specified, and the operation shown in the flowchart of FIG. 15 may be executed at the location. FIG. 17 is a block diagram illustrating the measurement apparatus 200 in this case.

  The current position acquisition unit 208 is configured by, for example, a GPS (Global Positioning System) or the like, and acquires current position information regarding the current position of the mobile object 240 (or the measurement device 200). The current position acquisition unit may be configured to acquire the current position information by communication or the like from an external device (not shown).

  The map information acquisition unit 210 acquires map information from an external map information distribution server or the like by communication, for example. Note that the measuring device 200 may include a map information storage unit that stores the acquired map information. The map information storage unit may store predetermined map information in advance.

  Here, the map information stored in the map information storage unit includes feature information including various information related to the features. The feature information may be managed and stored separately from the map information. The feature information includes at least information regarding the position where the feature exists.

  Based on the current position information acquired by the current position acquisition unit 208 and the feature information included in the map information acquired by the map information acquisition unit 210, the execution position specifying unit 212 generates “stray light to be described later”. The position or region suitable for executing the “process for specifying the irradiation timing of the electromagnetic wave” is specified. Specifically, a position around the current position and where no feature that reflects the electromagnetic wave is present in the direction in which the electromagnetic wave is irradiated is specified as a position or a region suitable for executing the processing.

  Here, the method of correcting the light source drive signal set in the control unit 204 by the correction unit 206 is the same as the method of generating the light source drive signal set in the control unit 204 by the setting device 300 of the first embodiment. Hereinafter, a method in which the correction unit 206 corrects the light source drive signal will be exemplified.

<Example 1 of Method for Correcting Light Source Drive Signal>
FIG. 15 is a first flowchart illustrating the flow of a procedure for generating a light source drive signal. The operation shown in the flowchart of FIG. 15 is repeatedly executed, for example, at a predetermined frequency (for example, once per minute). The method for correcting the light source drive signal in the flowchart of FIG. 15 is the same as the method of generating the light source drive signal to be set in the control unit 204 from the default signal in the flowchart of FIG.

  Further, the operation shown in the flowchart of FIG. 15 is repeatedly executed at a predetermined frequency when the mobile object 240 (or the measuring device 200) reaches the position or area specified by the execution position specifying unit 212 described above. It may be. For example, before starting this operation, the execution position specifying unit 212 specifies a position or a region suitable for executing “a process of specifying the irradiation timing of electromagnetic waves that generate stray light” in advance, and the current position The operation shown in the flowchart of FIG. 15 is started when the current position indicated by the current position information acquired by the acquisition unit 208 matches the specified position (or when it is included in the specified area). . Note that the measurement apparatus 200 may be configured to stop the operation when the current position is outside the specified position or region.

  The correction unit 206 acquires the measurement result obtained by the measurement apparatus 200 and identifies the irradiation timing of the electromagnetic wave that generated stray light (S302). The specific process performed by the correction unit 206 in S302 is the same as the process performed by the setting device 300 in S106.

  The correcting unit 206 determines whether or not one or more irradiation timings of the electromagnetic wave that generated the stray light are specified in S302 (S304). When no irradiation timing of the electromagnetic wave that generated the stray light is specified (S304: NO), the process of FIG. 15 ends. In this case, no stray light is generated in the control using the current light source drive signal. Therefore, the light source drive signal is not corrected.

  On the other hand, when one or more irradiation timings of electromagnetic waves that generate stray light are specified (S304: YES), the correction unit 206 corrects a part of the light source drive signal currently set in the control unit 204 (S306). ). Specifically, the correction unit 206 changes, from among the irradiation timings of the electromagnetic waves in the light source driving signal before the correction, only the irradiation timing of the electromagnetic waves in which stray light is generated as the corrected light source driving signal. In other words, the corrected light source drive signal is (1) the irradiation timing of the electromagnetic wave that generated stray light in the uncorrected light source drive signal is shifted by a predetermined clock k from the irradiation timing in the uncorrected light source drive signal. 2) The other electromagnetic wave irradiation timings coincide with the irradiation timings in the light source drive signal before correction. As described above, the relationship between the light source drive signal before correction in S306 and the light source drive signal after correction is the same as the relationship between the default signal and the light source drive signal set in the control unit 204 in S110 of FIG.

<Example 2 of Method for Correcting Light Source Drive Signal>

  FIG. 16 is a second flowchart illustrating the flow of the procedure for generating the light source drive signal. The operation shown in the flowchart of FIG. 16 is repeatedly executed, for example, at a predetermined frequency (for example, once per minute). Note that the method of correcting the light source drive signal in the flowchart of FIG. 16 is the same as the method of generating the light source drive signal to be set in the control unit 204 from the default signal in the flowchart of FIG.

  The correction unit 206 acquires the measurement result obtained by the measurement apparatus 200 and identifies the irradiation timing of the electromagnetic wave that generated stray light (S402). The correcting unit 206 sets an initial value 1 to the variable i representing the shift amount (S404). S406 to S418 is a loop process B that is repeatedly executed while the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value. In step S406, the correction unit 206 determines whether the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value. When the number of irradiation timings of electromagnetic waves that generate stray light is not equal to or greater than a predetermined value, the processing in FIG. 16 ends. On the other hand, if the number of irradiation timings of electromagnetic waves that generate stray light is greater than or equal to a predetermined value, the processing in FIG. 16 proceeds to S408.

  In step S <b> 408, the correction unit 206 sets a signal obtained by shifting the light source driving signal before correction as a whole by + i clocks in the control unit 204 as a corrected light source driving signal. The correction unit 206 acquires a measurement result by the measurement device 200 that operates using the light source drive signal, and identifies the irradiation timing of the electromagnetic wave that generated stray light (S410).

  The correcting unit 206 determines whether or not the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value (S412). If the number of irradiation timings of electromagnetic waves that generate stray light is not equal to or greater than a predetermined value (S412: NO), the process of FIG. 16 ends. On the other hand, if the number of irradiation timings of electromagnetic waves that generate stray light is equal to or greater than a predetermined value (S412: YES), the process of FIG. 11 proceeds to S414.

  In S414, the correction unit 206 sets a signal obtained by shifting the light source driving signal before correction as a whole by -i clocks in the control unit 204 as a corrected light source driving signal. The correction unit 206 acquires a measurement result by the measurement device 200 that operates using the light source drive signal, and specifies the irradiation timing of the electromagnetic wave that generated the stray light (S416). The correcting unit 206 adds 1 to i (S418).

  S420 is the end of the loop process B. Therefore, the processing in FIG. 11 proceeds to S406.

  According to the measurement device 200 of the present embodiment, the error occurs inside the measurement unit 202 while the measurement device 200 is in operation (for example, while the measurement device 200 is being used in a car that is running in the automatic driving mode). Stray light can be suppressed.

  Here, even if the measuring apparatus 200 is appropriately set so that no stray light is generated before the operation of the measuring apparatus 200 is started, stray light is generated inside the measuring apparatus 200 while the measuring apparatus 200 is in operation. There is a possibility that. For example, stray light may be generated due to the positional relationship between the irradiator 10 and the optical system 20 being shifted due to the influence of vibration applied to the measuring apparatus 200.

  Therefore, the measurement apparatus 200 according to the present embodiment detects the occurrence of stray light during the operation of the measurement apparatus 200 and corrects the light source drive signal. By doing so, the generation of stray light inside the measuring apparatus 200 can be more reliably suppressed. Moreover, it becomes possible to perform an appropriate correction by performing the correction in a situation where there is no feature around the moving body (measurement device).

<Example of hardware configuration>

  The hardware configuration of the measurement apparatus 200 according to the second embodiment is represented by, for example, FIGS. 4 to 6 in the same manner as the hardware configuration of the measurement apparatus 200 according to the first embodiment. In the present embodiment, the program module stored in the storage device 108 further includes a program that implements the functions described in the present embodiment.

  In FIG. 14, the correction unit 206 and the control unit 204 are described as separate functional configuration units, but the correction unit 206 may be a functional configuration unit included in the control unit 204. In this case, the process performed by the correction unit 206 described above can also be expressed as a process performed by the control unit 204.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are illustrations of this invention, The combination of said each embodiment or various structures other than the above can also be employ | adopted.

  This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2006-232162 for which it applied on November 30, 2016, and takes in those the indications of all here.

Claims (14)

A measuring unit that scans by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is irradiated to the outside and reflected by the reflector;
A control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit;
The measurement device, wherein the number of times the measurement unit irradiates the electromagnetic wave received with a strength of a predetermined value or more in one scan by the measurement unit is less than the predetermined number. A setting device for setting a measurement device,
The measuring device is
A measuring unit that scans by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is irradiated to the outside and reflected by the reflector;
A control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit using a drive signal;
The setting device
Operate the measurement device in which a predetermined signal is set as the drive signal, obtain a measurement result by the measurement device,
By changing the irradiation timing indicated by the predetermined drive signal for the electromagnetic wave received by the measurement device with an intensity of a predetermined value or more, it is received with an intensity of a predetermined value or more in one scan by the measurement unit. A setting device that makes the number of irradiation times of electromagnetic waves less than a predetermined number. Using the acquired measurement result, specify the timing at which the measurement device irradiates the electromagnetic wave received with a strength of a predetermined value or more by the measurement device,
The setting according to claim 2, wherein a signal obtained by changing only the specified timing before or after a predetermined clock among the irradiation timing of the electromagnetic wave indicated by the predetermined signal is set as the drive signal in the control unit. apparatus. It is determined whether or not the number of times the measurement unit irradiates electromagnetic waves received with a strength of a predetermined value or more in a single scan by the measurement unit is a predetermined number of times,
3. The control unit according to claim 2, wherein when the number of times is determined to be equal to or greater than the predetermined number, a signal obtained by shifting the entire predetermined signal forward or backward by a predetermined clock is set as the drive signal in the control unit. Setting device. A measuring device setting method,
The measuring device is
A measuring unit that scans by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is irradiated to the outside and reflected by the reflector;
A control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit using a drive signal;
The setting method is
Operating the measurement device in which a predetermined signal is set as the drive signal, and obtaining a measurement result by the measurement device;
By changing the irradiation timing indicated by the predetermined drive signal for the electromagnetic wave received by the measurement device with an intensity of a predetermined value or more, it is received with an intensity of a predetermined value or more in one scan by the measurement unit. Setting the number of times of irradiation of electromagnetic waves less than a predetermined number of times.   The program which makes a computer perform each step of the setting method of Claim 5. A measuring unit that scans by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is irradiated to the outside and reflected by the reflector;
A control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit using a drive signal;
A correction unit for correcting the drive signal,
The correction unit is
By changing the irradiation timing indicated by the drive signal for the electromagnetic wave received by the measurement unit with an intensity of a predetermined value or more, the electromagnetic wave received with the intensity of a predetermined value or more in one scan by the measurement unit A measuring device that makes the number of irradiations less than a predetermined number.   8. The correction unit according to claim 7, wherein, of the irradiation timing indicated by the drive signal, the correction unit changes only the irradiation timing of the electromagnetic wave received at a strength equal to or greater than a predetermined value in the measurement unit before or after a predetermined clock. Measuring device.   The measurement device according to claim 7, wherein the correction unit changes all irradiation timings of the electromagnetic wave indicated by the drive signal before or after a predetermined clock. A correction method executed by a measuring device,
The measuring device is
A measuring unit that scans by receiving the electromagnetic wave that is irradiated from the light source through the optical system and is irradiated to the outside and reflected by the reflector;
A control unit that controls a direction in which the electromagnetic wave is emitted from the measurement unit using a drive signal;
In the correction method, by changing the irradiation timing indicated by the drive signal for the electromagnetic wave received by the measurement device with an intensity greater than or equal to a predetermined value, the intensity is greater than or equal to a predetermined value in one scan by the measurement unit. The correction method which has the step which makes the frequency | count of irradiation of the received electromagnetic waves less than predetermined times.   The program which makes a computer perform each step of the correction method of Claim 10. A measuring unit having a light source, and a receiving unit that receives the electromagnetic wave irradiated from the light source through the optical system and reflected by a reflector;
A control unit that controls a direction in which the electromagnetic wave is irradiated from the measurement unit,
The control unit changes the irradiation timing of the measurement unit when the reception unit receives the reflected light reflected by the optical system from the light source with the intensity of a predetermined level or more. Measuring device. Using the acquired measurement result, specify the timing at which the measurement device irradiates the electromagnetic wave received with a strength of a predetermined value or more by the measurement device,
The setting device according to claim 2, wherein the control unit controls the measurement unit so that the electromagnetic wave is not irradiated from the light source at the specified timing among the irradiation timings of the electromagnetic wave indicated by the predetermined signal. . A measuring unit having a light source, and a receiving unit that receives the electromagnetic wave irradiated from the light source through the optical system and reflected by a reflector;
A control unit that executes a process of changing the irradiation timing of the electromagnetic wave when the receiving unit receives the reflected light reflected by the optical system with the intensity of the electromagnetic wave emitted from the light source; ,
Have
The control unit executes the processing when it is determined that there is no object that reflects the electromagnetic wave in a direction around the measurement apparatus and in the direction in which the electromagnetic wave is irradiated. .

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