JP6449545B2 - Distance measuring device - Google Patents

Description

  The present invention relates to a distance measuring device that measures the distance to a target by irradiating an electromagnetic wave toward the target and receiving the reflected wave.

  A device that corrects the distance to a target with reference to the distance to the ground is known as the distance measuring device (see, for example, Patent Document 1).

JP 2007-232499 A

However, the distance measuring apparatus has a problem that the distance correction becomes unstable because the distance to the ground and the reflectance of the electromagnetic wave by the ground change.
Therefore, in view of such problems, in a distance measuring device that measures the distance to a target by irradiating an electromagnetic wave toward the target and receiving the reflected wave, the distance can be corrected more accurately. It is an object of the present invention.

In the distance measuring device of the present invention, the distance correcting means includes a measurement distance measured by irradiating the electromagnetic wave with the distance to the reference reflector (50) provided in advance within the irradiation range of the electromagnetic wave as a reference distance, and a reference distance. The distance to the target is corrected using the difference between and.

  That is, the measurement distance and the reference distance should be the same distance, but if there is a difference between these distances, it is considered that an error has occurred in the distance to the target. Therefore, in the present invention, the distance to the target is corrected according to the difference between the measurement distance and the reference distance, and the distance measurement device and the distance measurement device can be accurately measured so that the difference between the measurement distance and the reference distance can be accurately measured. The distance to the reference reflector whose relative position is fixed is measured.

  According to such a distance measuring device, the distance to the reference reflector does not change, and the difference between the measurement distance and the reference distance can be measured accurately, so that the distance to the target can be corrected more accurately. Can do.

  In order to achieve the above object, the computer may be a distance measurement program for realizing the computer as each means constituting the distance measuring device. Further, the descriptions in the claims can be arbitrarily combined as much as possible. At this time, a part of the configuration may be excluded within a range in which the object of the invention can be achieved.

It is a block diagram showing a schematic structure of distance measuring device 1 of a 1st embodiment to which the present invention was applied. It is a top view which shows the example of arrangement | positioning of the distance measuring device 1 and the reference | standard reflector 50 in 1st Embodiment. 4 is a timing chart showing timings at which various signals are output in the distance measuring device 1. It is a flowchart which shows the distance calculation process which the control part 11 (CPU12) of the distance measuring device 1 performs in 1st Embodiment. 4 is a graph showing an example of a waveform of a reflected wave obtained by the light receiving unit 30. It is the top view and side view which show the example of arrangement | positioning of the distance measuring device 1 and the reference | standard reflector 50 in the modification of 1st Embodiment. It is a block diagram which shows schematic structure of the distance measuring devices 2 and 3 of 2nd Embodiment. It is a top view which shows the example of arrangement | positioning of the distance measuring devices 2 and 3 and the reference | standard reflector 50 in 2nd Embodiment. It is a flowchart which shows the distance calculation process which the control part 11 (CPU12) of the distance measurement apparatus 2 performs in 2nd Embodiment. It is a graph which shows an example of the map utilized when calculating | requiring temperature from delay time in the distance measuring device. It is a flowchart which shows the distance calculation process which the control part 11 (CPU12) of the distance measurement apparatus 3 performs in 2nd Embodiment. 6 is a graph showing an example of a map used when a delay time is obtained from a temperature in the distance measuring device 3.

Embodiments according to the present invention will be described below with reference to the drawings.
[First Embodiment]
[Configuration of this embodiment]
A distance measuring device 1 to which the present invention is applied is mounted on a vehicle such as a passenger car, for example, and irradiates a target (a target such as a pedestrian or an obstacle including other vehicles) with a laser beam which is a type of electromagnetic wave. The laser radar is configured to measure the distance to the target based on the timing of receiving the reflected wave. As shown in FIG. 1, the distance measuring device 1 includes a distance calculating unit 10, a light emitting unit 20, and a light receiving unit 30.

  The distance calculation unit 10 has a function of controlling the emission of laser light by the light emitting unit 20 and calculating the distance to the target according to the light reception signal from the light receiving unit 30. Specifically, the distance calculation unit 10 includes a control unit 11 and an amplification unit 15.

  The control unit 11 is configured as a computer including a CPU 12 and a memory 13 such as a ROM or a RAM. The CPU 12 executes a program (including a distance measurement program) stored in the memory 13.

  The control unit 11 outputs a scanning command for scanning the laser light to the light emitting unit 20 and outputs a measurement start light emission instruction for emitting the laser light to the light emitting unit 20 via the amplification unit 15. The amplification unit 15 is configured as a buffer that amplifies the measurement start light emission instruction (light emission instruction) from the control unit 11 and outputs the amplified light to the light emission unit 20.

  The control unit 11 includes a measurement unit 16 including an AD conversion unit 17 and a distance calculation unit 18. The AD conversion unit 17 is configured as a known AD conversion circuit that converts a light reception signal (analog value) obtained by the light reception unit 30 into a digital value.

  The distance calculation unit 18 calculates the distance to the target or the reference reflector 50 (see FIG. 2) according to the digital value from the AD conversion unit 17. The distance calculation unit 18 is realized as a process by the CPU 12.

  Next, the light emitting unit 20 has a configuration for scanning a laser beam within a predetermined irradiation range in accordance with a command from the control unit 11. That is, the light emitting unit 20 includes a laser diode 21, a laser driving circuit 22, an operation unit 23, and a scanning driving circuit 24.

  The laser drive circuit 22 is a circuit that causes the laser diode 21 to emit light in accordance with a light emission instruction from the distance calculation unit 10. The operation unit 23 includes a mirror that can be rotationally driven to scan the laser light emitted from the laser diode 21, and the scanning drive circuit 24 is a circuit for driving the mirror.

  Next, the light receiving unit 30 has a configuration for outputting a voltage corresponding to the intensity of the reflected light. That is, the light receiving unit 30 includes a photodiode 31 and an amplifier circuit 32. The amplifier circuit 32 is configured as a buffer that amplifies and outputs a signal from the photodiode 31.

  For example, as shown in FIG. 2, the distance measuring device 1 configured as described above is disposed on the left side surface of the rear portion of the vehicle, and the entire area on the left side of the vehicle is within the laser light irradiation range (scanning range). . In addition, the reference reflector 50 is disposed at an end portion within the irradiation range (for example, within a range within about 5% of the entire range from the end of the irradiation range).

  In this reference reflector 50, a substance having a preset reflectance is arranged on the surface of the vehicle (a mirror in the example of FIG. 2), and the distance from the light emitting unit 20 and the light receiving unit 30 is preset. The reference distance is set. When the laser beam is irradiated on the reference reflector 50 (B), the distance measuring device 1 (L) measures the distance to the reference reflector 50 and targets other than the reference reflector 50 (target (T)) ) Will measure the distance to the target.

  Here, the distance measuring device 1 is affected by delay inside the device when measuring the distance. That is, as shown in FIG. 3, there is a light emission side delay time from when the control unit 11 outputs the measurement start light emission instruction to when the laser light is actually emitted, and the reflected light enters the photodiode 31. Until the distance is measured after (received reflected light), a delay time on the light receiving side occurs.

Therefore, in the present embodiment, the distance calculation processing described below is performed in consideration of these delay times.
[Process of this embodiment]
That is, the control unit 11 of the distance measuring device 1 performs the distance calculation process shown in FIG. The distance calculation process is a process that is started each time laser light is emitted from the distance measuring device 1, for example.

  In this process, it is first determined whether or not to irradiate laser light in the direction in which the reference reflector 50 exists (S110). In this process, the direction of the reference reflector 50 is recorded in advance, and determination is made according to whether or not the direction in which the scanning unit 14 reflects the laser light is this direction.

  When the laser beam is not irradiated in the direction in which the reference reflector 50 exists (S110: NO), the laser output is set to a relatively high HI (S120) level (S120), and light emission is performed with this setting (S130).

  That is, the measurement start light emission instruction and the command for driving the scanning unit 14 are transmitted to the light emitting unit 20. When this process is completed, the measurement time until the reflected wave received by the light receiving unit 30 is immediately received is calculated (S140).

  Then, as shown in FIG. 5A, after a short time has elapsed since the light emission was performed (distance measurement start timing), noise (light emission trigger) due to the light emission was detected, and then the target (target ), The reflected wave from the target is detected at a timing according to the distance up to. In this process, the time until this reflected wave is detected is obtained as the measurement time.

  Subsequently, the time until the target is detected is corrected (S150). That is, the time obtained by subtracting the reference time from the measurement time and further adding the actual time is used as the corrected time. Here, the reference time is a measurement time when the reference reflector 50 is detected, which is obtained in the processes of S240 and S250 described later.

  The reference time includes the above-described light emission side delay time and light reception side delay time as well as the measurement time for detecting a target. Note that the latest time recorded in the memory 13 is used as this reference time.

  The real time is the time required for light to pass through the reference distance (the distance of the optical path from the light emitting unit 20 via the reference reflector 50 to the light receiving unit 30). When the corrected time is obtained in this way, the light emission side delay time and the light receiving side delay time are canceled (erased), and the time corresponding to the distance to the target (from the light emitting unit 20 via the target to the light receiving unit 30). Only the time required for the light to pass through the distance of the optical path to be obtained.

Subsequently, a value obtained by multiplying the corrected time by the speed of light and dividing by 2 is obtained as a corrected distance (S160). When such processing is completed, the distance calculation processing is ended.
By the way, in the processing of S110, when laser light is irradiated in the direction in which the reference reflector 50 exists (S110: YES), the laser output is set to a relatively low LOW level (S220), and light emission is performed with this setting. (S230). When irradiating the reference reflector 50 with the laser light, the output of the laser light is lower than the case where the reference reflector 50 is not irradiated with the laser light. This is because the reflected wave from the reference reflector 50 is less likely to be buried in the noise when the distance is close and laser light is emitted.

When this process ends, the measurement time until the reflected wave received by the light receiving unit 30 is immediately received is calculated (S240).
In this case, as shown in FIG. 5B, noise (light emission trigger) due to light emission is detected after a short time has elapsed since the light emission was performed (distance measurement start timing). A reflected wave from the reference reflector 50 is detected at a near timing.

  In order to improve the timing detection accuracy of the reflected wave from the reference reflector 50, the time interval between the noise caused by the inside of the sensor such as light emission noise (inside the distance detection unit 10) and the reflected wave from the reference reflector 50 It is better to secure a certain distance between the sensor and the reference reflector 50 in order to ensure the above (it is desirable to ensure a long time indicated by the arrow in FIG. 5B).

Subsequently, the obtained measurement time is stored in the memory 13 as a reference time (S250), and the distance calculation process is terminated.
[Effects of this embodiment]
In the distance measuring device 1 described in detail above, the distance calculating unit 10 is provided at a position that becomes a reference distance set in advance within the irradiation range of the electromagnetic wave, and the reference reflection whose relative position to the distance measuring device 1 is fixed. The distance to the target is corrected using the difference between the measurement distance measured by irradiating the electromagnetic wave with the object 50 and the reference distance.

  According to such a distance measuring device 1, the distance to the reference reflector 50 does not change, and the difference between the measurement distance and the reference distance can be accurately measured. It can be carried out.

  Further, in the distance measuring apparatus 1, the distance calculating unit 10 calculates a measurement time (first time) from instructing the target to emit electromagnetic waves until the detection of the reflected wave is completed, and the reference reflecting object A reference time (second time) from when the electromagnetic wave is instructed to 50 to when the detection of the reflected wave is completed is calculated. Then, the distance calculation unit 10 subtracts the reference time from the measurement time, obtains a corrected time obtained by adding a real time (third time) corresponding to the reference distance, and further, a distance corresponding to the corrected time. Is the corrected distance.

  That is, the reference time is obtained by adding the delay time inside the apparatus to the real time, and the measurement time is obtained by adding the delay time to the time corresponding to the distance to the target. Therefore, if the reference time is subtracted from the measurement time and the real time is added to this value, only the time corresponding to the distance to the target can be obtained.

Therefore, according to such a distance measuring device 1, the distance to the target can be corrected with higher accuracy.
Further, in the distance measuring device 1, the distance calculation unit 10 reduces the output of the electromagnetic wave when emitting the electromagnetic wave to the reference reflector 50 than when irradiating the target with the electromagnetic wave.

  According to such a distance measuring device 1, even when the reference reflector 50 has to be disposed at a relatively short distance, noise at the time of emitting an electromagnetic wave can be reduced. Therefore, it is possible to make it difficult for the reflected wave from the reference reflector 50 to be buried in noise, so that the distance to the reference reflector 50 can be easily measured accurately.

In the distance measuring device 1, the distance calculation unit 10 irradiates the reference reflector 50 disposed at the end within the irradiation range of the electromagnetic wave with the electromagnetic wave.
According to such a distance measuring device 1, the end within the irradiation range may be unsuitable for detection of a target located at a relatively long distance, such as distortion, but it is disposed at a relatively short distance. If the reference reflector 50 is often detected, it can be detected satisfactorily. Therefore, the irradiation range can be used effectively.

The distance measuring device 1 is mounted on a vehicle and irradiates the reference reflector 50 arranged on the surface of the vehicle with electromagnetic waves.
According to such a distance measuring device 1, even if it is mounted on a vehicle, it can function well.

[Modification of First Embodiment]
In the first embodiment, the distance measuring device 1 and the reference reflector 50 are arranged on the side surface of the vehicle, but other arrangements can be adopted. For example, as shown in FIG. 6, the distance measuring device 1 is arranged so that the front of the vehicle is within the laser light irradiation range, and the reference reflector is positioned at a position corresponding to the lower end in the vertical direction within the irradiation range. 50 may be arranged.

Even if it does in this way, the effect similar to the said 1st Embodiment can be enjoyed.
[Second Embodiment]
Next, different forms of distance measuring devices 2 and 3 will be described. In the present embodiment (second embodiment), only the portions different from the distance measuring device 1 of the first embodiment will be described in detail, and the same portions as those of the distance measuring device 1 of the first embodiment will be denoted by the same reference numerals. Therefore, the description is omitted.

  In the present embodiment, the distance measurement device 2 transmits temperature information indicating the temperature of the device itself (vehicle ambient temperature) to the distance measurement device 3, and the distance measurement device 3 corrects the measurement distance based on the temperature information. It is configured to perform an operation.

  As shown in FIG. 7, the distance measuring devices 2 and 3 include a communication unit 19 in the distance calculation unit 10. The communication unit 19 is configured as a communication module that communicates with other distance measuring devices.

  As shown in FIG. 8, the distance measuring device 2 is disposed such that the front of the vehicle is within the laser light irradiation range, and the reference reflector 50 is disposed within the irradiation range. On the other hand, the distance measuring device 3 is disposed so that the rear of the vehicle is within the irradiation range, and no reference reflector is disposed within the irradiation range.

  In such a distance measuring apparatus 2, a distance calculation process as shown in FIG. 9 is performed. That is, in the distance calculation process shown in FIG. 4, the processes of S310 to S330 are additionally performed after the process of S250.

  Specifically, in the distance calculation process shown in FIG. 9, after the reference time is recorded in the memory 13 in the process of S250, the delay time is obtained by subtracting the actual time from the reference time (S310). Then, the temperature is obtained by referring to a map (map1) showing the relationship between the delay time and the temperature (atmosphere temperature) obtained experimentally in advance by the distance measuring device 2 (S320).

  Here, in this map, for example, as shown in FIG. 10, when the delay time is input, the temperature is uniquely determined. Subsequently, the temperature information is transmitted to the distance measuring device 3 (S330), and the distance calculation process by the distance measuring device 2 is ended.

  Further, the distance measuring device 3 performs a distance calculation process as shown in FIG. In the distance calculation processing by the distance measuring device 3, the processing of S120 to S140 of the distance calculation processing shown in FIG. 4 is performed, and then the processing of S360 to S380 is added and performed.

  That is, in the distance calculation processing by the distance measuring device 3, as shown in FIG. 11, the temperature information transmitted from the distance measuring device 2 is acquired after the processing of S140 (S360). Then, the delay time is obtained by referring to a map (map 2) showing the relationship between the temperature (atmosphere temperature) experimentally obtained in advance by the distance measuring device 3 and the delay time (S370).

  Here, in this map, for example, as shown in FIG. 12, when the temperature is input, the delay time is uniquely determined. Subsequently, the corrected time is obtained (S380).

  The post-correction time here can be obtained by subtracting the delay time from the measurement time. Note that the arithmetic expression for obtaining the corrected time in this process is equivalent to the arithmetic expression in the process of S150.

Subsequently, the process of S160 described above is performed, and the distance calculation process by the distance measuring device 3 is terminated.
[Effects of Second Embodiment]
In the distance measuring device 2 described in detail above, the distance calculating unit 10 is required for processing in the distance measuring device 2 in the time from the instruction of emission of electromagnetic waves to the end of detection of the reflected wave. Calculate the delay time representing the time. Then, the temperature corresponding to the calculated delay time is estimated according to a map indicating the relationship between the delay time and temperature prepared in advance, and the estimated temperature is output to another distance measuring device 2.

  That is, since it has been experimentally determined that the delay time varies depending on the temperature, the temperature is estimated from the delay time. Therefore, according to such a distance measuring device 2, since the temperature estimated from the delay time is provided to the other distance measuring device 2, even if the other distance measuring device 2 cannot measure the delay time, The delay time can be estimated from the temperature.

  Further, in the distance measuring device 3, the distance calculating unit 10 acquires the temperature from another device, and processes the distance measuring device 3 in the time from the instruction to emit the electromagnetic wave to the end of the detection of the reflected wave. The delay time indicating the time required for the above is estimated according to a map indicating the relationship between the temperature and the delay time prepared in advance. Then, based on the delay time, the distance to the target is corrected.

According to such a distance measuring device 3, since the delay time can be estimated based on the acquired temperature, the distance correction using the delay time can be performed accurately.
Moreover, according to such a distance measuring device 3, since the exact temperature based on the delay time of the other distance measuring device 3 can be acquired, the distance to the target can be accurately measured.

[Modification of Second Embodiment]
In the second embodiment, the distance measuring devices 2 and 3 function effectively even when the temperature characteristics are different, but when the distance measuring devices 2 and 3 have the same temperature characteristics, the reference The time may be configured to be transmitted / received by communication, and the distance measuring device 3 may obtain the corrected time using the reference time. That is, in the distance calculation process shown in FIG. 11, the process of S150 shown in FIG. 4 may be performed instead of the process of S380.

Even if it does in this way, the effect similar to the said 2nd Embodiment can be enjoyed.
[Other Embodiments]
The present invention is not construed as being limited by the above embodiment. Moreover, the aspect which abbreviate | omitted a part of structure of said embodiment as long as the subject could be solved is also embodiment of this invention. An aspect configured by appropriately combining the above-described plurality of embodiments is also an embodiment of the present invention. Moreover, all the aspects which can be considered in the limit which does not deviate from the essence of the invention specified only by the wording described in the claims are embodiments of the present invention. Further, the reference numerals used in the description of the above embodiments are also used in the claims as appropriate, but they are used for the purpose of facilitating the understanding of the invention according to each claim, and the invention according to each claim. It is not intended to limit the technical scope of

For example, in the above embodiment, the distance is measured using laser light, but the distance may be measured using electromagnetic waves such as other light waves or radio waves.
Further, in FIG. 2, the light emitting unit 20 and the light receiving unit 30 may be disposed at the position indicating the distance measuring device 1, and the distance calculating unit 10 of the distance measuring device 1 is at the position indicating the distance measuring device 1. There is no need to be placed.

[Correspondence between Configuration of Embodiment and Means of Present Invention]
Of the processes executed by the control unit 11 in the above embodiment, the processes of S130 and S140 correspond to the first time calculating means in the present invention, and the processes of S150, S160 and S380 in the above embodiment are referred to in the present invention. It corresponds to the distance correction means. Moreover, the process of S220 in the said embodiment is equivalent to the output reduction means said by this invention, and the process of S230-S250 in the said embodiment is equivalent to the 2nd time calculating means said by this invention.

  Further, the process of S310 in the above embodiment corresponds to the delay time calculating means in the present invention, and the process of S320 in the above embodiment corresponds to the temperature estimating means in the present invention. Further, the process of S330 in the above embodiment corresponds to the temperature output means referred to in the present invention, and the process of S360 in the above embodiment corresponds to the temperature acquisition means referred to in the present invention.

Further, the process of S370 in the above embodiment corresponds to the delay time estimating means in the present invention, and the process of S380 in the above embodiment corresponds to the delay correction means in the present invention.
Further, the measurement time in the above embodiment corresponds to the first time in the present invention, the reference time in the above embodiment corresponds to the second time in the present invention, and the actual time in the above embodiment corresponds to the first time in the present invention. Corresponds to 3 hours.

  DESCRIPTION OF SYMBOLS 1-3 ... Distance measuring device, 10 ... Distance calculating part, 11 ... Control part, 12 ... CPU, 13 ... Memory, 14 ... Scanning part, 15 ... Amplifying part, 16 ... Measuring part, 17 ... AD converting part, 18 ... Distance calculating unit, 19 ... communication unit, 20 ... light emitting unit, 21 ... laser diode, 22 ... laser driving circuit, 23 ... operating unit, 24 ... scanning driving circuit, 30 ... light receiving unit, 31 ... photodiode, 32 ... amplifying circuit 50: Reference reflector.

Claims (8)

A distance measuring device (1, 2) that is mounted on a vehicle, irradiates an electromagnetic wave toward a target, and measures the distance to the target by receiving the reflected wave,
The distance measuring device irradiates the reference reflector (50) disposed on the surface of the vehicle with electromagnetic waves,
Furthermore,
As reference distance a distance to the reference reflector in the irradiation range of the electromagnetic wave, to correct the distance to a target by using the difference between the measured distance and the previous SL reference distance measured by irradiating the electromagnetic wave distance correction means and (S150, S160, S380),
First time calculating means (S130, S140) for calculating a first time from when the target is instructed to emit the electromagnetic wave to when the detection of the reflected wave is completed;
Second time calculation means (S230 to S250) for calculating a second time from when the reference reflector is instructed to emit the electromagnetic wave until the detection of the reflected wave is completed;
A delay time calculating means (S310) for calculating a delay time representing a time required for processing in the distance measuring device out of a time from instructing emission of the electromagnetic wave to completion of detection of the reflected wave;
Temperature estimation means (S320) for estimating a temperature according to the calculated delay time according to a map indicating the relationship between the delay time and temperature prepared in advance;
Temperature output means (S330) for outputting the estimated temperature to another distance measuring device;
With
The distance correction means subtracts the second time from the first time to obtain a corrected time by adding a third time that is a time corresponding to the reference distance, and further, a distance corresponding to the corrected time Is a distance after correction. The distance measuring device according to claim 1,
Output reduction means (S220) for reducing the output of the electromagnetic wave when emitting the electromagnetic wave to the reference reflector.
A distance measuring device comprising: A distance measuring device (1, 2) that is mounted on a vehicle, irradiates an electromagnetic wave toward a target, and measures the distance to the target by receiving the reflected wave,
As reference distance the distance to the reference reflector (50) in the irradiation range of the electromagnetic wave, the distance to a target by using the difference between the measured distance and the previous SL reference distance measured by irradiating the electromagnetic wave Distance correcting means (S150, S160, S380) for correcting;
When performing an electromagnetic wave emitted relative to the reference reflector, output reduction means for reducing the output of the electromagnetic wave and (S220),
A delay time calculating means (S310) for calculating a delay time representing a time required for processing in the distance measuring device out of a time from instructing emission of the electromagnetic wave to completion of detection of the reflected wave;
Temperature estimation means (S320) for estimating a temperature according to the calculated delay time according to a map indicating the relationship between the delay time and temperature prepared in advance;
Temperature output means (S330) for outputting the estimated temperature to another distance measuring device;
Equipped with a,
Furthermore,
The distance measuring device radiates electromagnetic waves to the reference reflector disposed on the surface of the vehicle.
Distance measuring device comprising a call. A distance measuring device (3) that measures the distance to a target by irradiating an electromagnetic wave toward the target and receiving the reflected wave,
Temperature acquisition means (S360) for acquiring the temperature from another device;
A delay time indicating a time required for processing in the distance measuring device out of a time from when the emission of the electromagnetic wave is instructed until the detection of the reflected wave is completed is a temperature and a delay time prepared in advance. A delay time estimating means (S370) for estimating according to a map indicating the relationship;
A delay correcting means (S380) for correcting the distance to the target based on the delay time;
With
The distance measuring device according to any one of claims 1 to 3 , wherein the other device is configured as the distance measuring device according to any one of claims 1 to 3 . A distance measuring device (3) that measures the distance to a target by irradiating an electromagnetic wave toward the target and receiving the reflected wave,
Temperature acquisition means (S360) for acquiring the temperature from another device;
A delay time indicating a time required for processing in the distance measuring device out of a time from when the emission of the electromagnetic wave is instructed until the detection of the reflected wave is completed is a temperature and a delay time prepared in advance. A delay time estimating means (S370) for estimating according to a map indicating the relationship;
A delay correcting means (S380) for correcting the distance to the target based on the delay time;
With
The other device is
A distance measuring device (1, 2) that measures the distance to a target by irradiating an electromagnetic wave toward the target and receiving the reflected wave,
The relative distance a distance to prearranged reference reflector 50 in the irradiation range of the electromagnetic wave, by utilizing the difference between the measured distance and the previous SL reference distance measured by irradiating the electromagnetic wave target Distance correction means (S150, S160, S380) for correcting the distance up to
A delay time calculating means (S310) for calculating a delay time representing a time required for processing in the distance measuring device out of a time from instructing emission of the electromagnetic wave to completion of detection of the reflected wave;
Temperature estimation means (S320) for estimating a temperature according to the calculated delay time according to a map indicating the relationship between the delay time and temperature prepared in advance;
Temperature output means (S330) for outputting the estimated temperature to another distance measuring device;
A distance measuring device comprising a distance measuring device. In the distance measuring device according to any one of claims 1 to 5,
The distance measuring device is mounted on a vehicle and irradiates an electromagnetic wave to a reference reflector disposed on the surface of the vehicle. In the distance measuring device according to any one of claims 1 to 6 ,
The distance measuring device is
A distance measuring device that irradiates an electromagnetic wave to a reference reflector disposed at an end in an irradiation range of the electromagnetic wave. Computer, according to claim 1 distance measuring program for causing to function as each means constituting the distance measuring apparatus according to any one of claims 7.

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