JPH1031064A - Scanning laser radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser radar device capable of reducing cost without causing dead angle in front sight for arranging of a self diagnostic element. SOLUTION: Oscillating scanning area of laser light projected from a projector 4 is widen to outside a set scanning angle area θ. And also a light receiving element 8 is arranged in a position at which the laser light projected from the projector 4 with the light oscillating scan across the set scanning angle area θ is reflected by a permeable window plate 2 and reaches and state of the projector 4 can be examined in a spare time of lookout a front object by monitoring an output signal of the light receiving element 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning laser radar apparatus suitable for application to, for example, an inter-vehicle distance control system and, more particularly, to a scanning laser radar apparatus having a self-diagnosis function of a light emitting and receiving device. .

[0002]

2. Description of the Related Art An example of the structure of a head in a conventional scanning laser radar device is shown in FIG. As shown in FIG. 1, the head portion of the scanning laser radar device is directed forward in a housing 3 having a light-transmitting window plate 2 (eg, glass or plastic) in a front window 1 thereof. A pair of light emitting and receiving devices 4 and 5 are arranged side by side on the left and right. The light emitter 4 constituting a pair of light emitter / receiver oscillates and scans the light emitting direction within the scanning angle range θ set in the left-right direction, and emits a laser pulse through the translucent window plate 2 to the front sector guard area. It is configured to light. The light receiver 5 forming a pair of light emitter / receiver is configured to receive the reflected light of the laser pulse reflected in the front sector guard area through the translucent window plate 2. That is, although not shown, the projector 4 includes a pulse-driven laser diode LD, a reflecting mirror that reflects light from the laser diode LD and is supported rotatably within a predetermined angle range, and The motor is mainly composed of a motor for rotating the mirror, and the rotation angle of the reflecting mirror is detected by a built-in sensor and output to the outside.

[0003] Such a scanning laser radar device is attached to, for example, a front bumper of a vehicle, and is used for measuring an inter-vehicle distance with a preceding vehicle. As is well known, the inter-vehicle distance control system sets an appropriate inter-vehicle distance calculated from the traveling speed of the vehicle as a target value, and a deviation between the target value and the inter-vehicle distance measured by the scanning laser radar device becomes zero. Thus, the inter-vehicle distance with the preceding vehicle is appropriately maintained while automatically controlling the accelerator and the brake.

Conventionally, this type of scanning laser radar apparatus has a self-diagnosis function in order to always assure that the light emitting and receiving devices 4 and 5 operate normally. In order to realize this self-diagnosis, the translucent window plate 2
The test light-receiving element 6 and the test light-emitting element 7 attached to the inner surface side of are used. The test light receiving element 6
It is attached to the inner surface of the translucent window plate 2 so as to be located at the end of the scanning angle range θ, and when the laser pulse emitted from the projector 4 irradiates the light receiving element 6, the light receiving element 6 By monitoring the output signal, it is possible to confirm that a laser pulse is actually being emitted from the projector 4. On the other hand, the test light emitting element 7 is similarly mounted on the inner surface side of the translucent window plate 2, emits light at an appropriate timing, and monitors the output of the light receiver 5. Can be confirmed to operate normally.

[0005]

However, the light receiving element 6 in such a conventional scanning type laser radar device is used.
In addition, since the arrangement of the light emitting element 7 blocks the front view of the light emitter 4 and the light receiver 5 though slightly,
There is a possibility that a blind spot may be generated in the front sector guard area by that much, and in addition to the light emitting and receiving devices 4 and 5, the light receiving element 6 and the light emitting element 7 are separately required for the test. There was a problem of being connected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional scanning laser radar apparatus, and an object thereof is to provide a blind spot in a front field of view due to the arrangement of a self-diagnosis element. An object of the present invention is to provide a scanning laser radar apparatus which does not cause the problem and can reduce the cost.

[0007]

According to the first aspect of the present invention, a pair of light emitting and receiving devices are arranged side by side in a housing having a light transmitting window plate on a front window thereof. Arranged, the light emitter constituting the pair of light emitter / receiver oscillates the light emitting direction within the scanning angle range set in the left and right direction, while passing the laser pulse through the translucent window plate to the front sector guard area. A scanning laser radar device that emits light, and a light receiver that constitutes the pair of light emitters and receivers receives the reflected light of the laser pulse reflected in the front sector guard area through the translucent window plate. In the state, while the swing scanning range of the laser pulse emitted from the projector is extended to outside the set scanning angle range, and the swing scanning is performed beyond the set scanning angle range. Said A light receiving element is arranged at a position where the laser light emitted from the optical device is reflected by the translucent window plate and arrives, and by monitoring an output signal of the light receiving element, the idle time of the forward object alertness is monitored. The present invention provides a scanning laser radar device characterized in that the state of the projector can be diagnosed.

According to the first aspect of the present invention, the swing scanning range of the laser light projected from the light projector is extended to outside the installed scanning angle range. Here, "extend to the outside" refers to the case where the swiveling scan range is physically expanded from the conventional one, and the physical swivel scan range remains the same as the conventional one, And the case where the end area of the scanning range that has not been used is used. That is, in general, the rotary reflecting mirror in this type of scanning laser radar device has a predetermined allowable rotation angle, but it does not actually correspond to the forward sector warning area but the entire swiveling scanning range, Since a small unused portion is usually left at both ends of the scanning range, the unused portion can be used for the operation test of the present invention. In addition, "Fan type warning area"
Means an area that the laser radar sets as an observation range.

Further, in the present invention, the position at which the laser beam projected from the light projector is reflected by the translucent window plate and reaches when the head is swung over the set scanning angle range. A light-receiving element is disposed in the device, and an output signal of the light-receiving element is monitored, so that the state of the projector can be diagnosed during the idle time of the forward object guard. Here, "light receiving element"
For example, a photodiode PD capable of detecting a signal from the laser diode LD can be used.

In the invention according to the first aspect, the operation test of the projector is mainly described.
Any other test method can be used for the light receiver. Therefore, a separate light emitting element may be provided as in the conventional case.

According to the first aspect of the present invention, the light receiving element does not obstruct the front field of view of the projector, so that no blind spot occurs in the front, and the light receiving element is out of the scanning angle range θ. Therefore, there is no restriction on the mounting position.

According to a second aspect of the present invention, in a housing having a translucent window plate on a front window thereof, a pair of light emitters and receivers are arranged side by side toward the front, respectively. The light emitter constituting the light emitter / receiver emits a laser pulse through the light transmitting window plate to the front fan-shaped guard area while swinging and scanning the light emitting direction within a scanning angle range set in the horizontal direction, In a scanning laser radar device configured to receive the reflected light of the laser pulse reflected by the front sector guard area through the translucent window plate, The oscillating scanning range of the emitted laser light is extended to outside the set scanning angle range, and the light is emitted from the projector in a state where the oscillating scanning is performed beyond the set scanning angle range. Sa By adjusting the arrangement of the light projector and the light receiver so that the laser light is reflected by the translucent window plate and reaches the light receiver, by monitoring the output signal of the light receiver, A scanning laser radar device characterized in that the state of the projector can be diagnosed during the idle time of the forward object guard.

According to the second aspect of the present invention, by adjusting the arrangement of the light emitter and the light receiver, the laser light emitted from the light emitter in a state where the head is swung beyond the set scanning angle range. The light is reflected by the translucent window plate and reaches the light receiver. Here, “adjusting the arrangement of the light emitter and the light receiver” includes not only the case where the arrangement relationship between the two is adjusted differently from the conventional one, but also the arrangement of both. The relationship remains the same as before, and the leaked light of the laser pulse emitted from the light emitter is reflected by the translucent window plate while the camera is swung over the set scan angle range. The case where the light reaches the light receiver includes both the case where the leaked light itself is used.

According to the second aspect of the present invention, the signal sequence output from the optical receiver in time series is
By extracting the part that deviates from the forward warning area and monitoring it, the operating state of the entire system including the emitter and receiver can be checked, and no light-receiving element and light-emitting element for testing are required at all. Therefore, cost can be reduced.

According to a third aspect of the present invention, there is provided a laser beam emitted from the light projector so as to monitor a level of an output signal of the light receiving element or the light receiver so that the output signal always falls within a specified range. The scanning laser radar device according to claim 1 or 2, further comprising servo control means for adjusting a pulse intensity.

According to the third aspect of the present invention, the level of the output signal of the light receiving element or the light receiving device in the first and second aspects is monitored, and the level of the output signal is monitored so that the level always falls within a specified range. The intensity of the emitted laser pulse is adjusted. That is, since the intensity of the laser pulse reaching the light receiving element or the light receiving device does not pass through the forward warning area, it always reflects the light emitting state of the laser diode accurately. By performing servo control based on the signal, the intensity of the laser diode that emits a laser pulse can be appropriately maintained.

The invention according to claim 4 of the present application is provided with abnormality processing means for issuing a predetermined abnormality output when the level of the output signal does not fall within a specified value due to the operation of the servo control means. The scanning laser radar device according to claim 3, wherein:

By using the above-mentioned servo control means, if all devices are normal, the intensity of the laser pulse should be properly maintained. However, if the laser diode itself becomes abnormal, If an abnormality occurs in the drive circuit, the intensity of the laser pulse may not be properly maintained. Therefore, in such a case, by issuing an abnormal output, an appropriate measure such as issuing an alarm to a vehicle occupant or automatically canceling the inter-vehicle distance control system becomes possible.

According to a fifth aspect of the present invention, in the state in which the head is swung beyond the set scanning angle range, the light is projected from the light emitter to the light receiving element or the light receiver. The scanning laser radar according to any one of claims 1 to 4, wherein a mirror is provided at a reflection position where the arriving laser light is reflected by the translucent window plate. In the device.

Generally, the material of the translucent window plate used in this type of scanning laser radar device is glass or plastic, which generates sufficient reflected light at the incident interface. If the laser pulse is totally reflected by using the surface, sensitivity in operation test and servo control will be further improved.

According to the invention described in claim 6 of the present application, the laser beam projected from the projector in a state where the laser beam is swung over the set scanning angle range is continuous light or pulsed light. The scanning laser radar device according to claim 1 or 2, wherein:

The "laser light" referred to here is not necessarily a pulse light because it is used for distance measurement. Therefore, the pulse light can be changed to the continuous light while the operation angle range is exceeded.

[0023]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the configuration of the head of the scanning laser radar device according to the present invention.

As shown in FIG. 1, a head portion of this scanning laser radar device has a light transmitting window plate 2
And a pair of light-emitting and light-receiving devices 4 and 5 are arranged side by side in the left and right directions in a housing 3 having The light emitter 4 constituting a pair of light emitters and receivers emits a laser pulse through the translucent window plate 2 to the front sector guard area while swinging and scanning the light emitting direction within the scanning angle range θ set in the left-right direction. It is configured to be. The light receiver 5 constituting a pair of light emitter / receiver is configured to transmit the reflected light of the laser pulse reflected in the front fan-shaped guard area to the translucent window plate 2.
It is configured to receive light through

On the other hand, in this scanning laser radar device, the swing scanning range of the laser pulse projected from the light projector 4 is extended by Δθ to outside the set scanning angle range θ. In the state where the head has been swung by Δθ beyond the set scanning angle range θ, the
A light-receiving element (for example, composed of a photodiode PD) 8 is disposed at a position where the laser pulse projected from the light-transmitting window plate 2 is reflected and arrives. Therefore, since the light receiving element 8 is arranged out of the scanning angle range θ, it does not obstruct the front view of the light projector 4.
In addition, since the degree of freedom increases in the mounting space,
There is not much restriction on the mounting space. still,
The configuration for the operation test on the side of the light receiver 5 is the same as the conventional one, and the light emitting element 7 is provided on the inner surface side of the translucent window plate 2.
The operation of the light receiver 5 is diagnosed by receiving the light from the light emitting element 7 and monitoring the output of the light receiver 5.

According to the first embodiment, while monitoring the output signal of the light receiving element 8, the state of emitting the laser pulse from the projector 4 is determined based on the signal level in the time zone beyond the scanning angle range θ. While it can be diagnosed,
It is possible to monitor the operation state of the light receiver 5 based on the signal level at the light emission timing of the light emitting element 7 while monitoring the output signal of the light receiver 5.

Although not shown in the figure, as described above, the light projector 4 reflects the laser pulse LD driven by the pulse and the laser pulse emitted from the laser diode LD in a predetermined angle range. And a motor for rotationally driving the reflecting mirror. The angular position of the reflecting mirror is output to the outside by a built-in sensor. It has become. On the other hand, the light receiver 5 is composed of a photodiode PD whose optical system has been adjusted so as to receive light from within a predetermined angle range in front, and detects the output level of the light receiver 5 and the detection level from the light projector 4 at that time. Based on the projected light angle and the laser pulse emission timing from the light projector 4, the distance and the angle to the front object can be measured by the principle of triangulation. It should be noted that various electronic circuits, which will be described in detail later, are used for this measurement process.

Next, a second embodiment of the present invention will be described. FIG. 2 is a schematic diagram showing a configuration of a head unit of a scanning laser radar device according to a second embodiment. still,
In the figure, the same components as those of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The feature of the second embodiment is that the projector 4
In addition, it is unnecessary to separately provide a light receiving element and a light emitting element for the operation test of the light receiver 5. As shown in the figure, also in this example, the swing scanning range of the laser pulse projected from the light projector 4 is extended by Δθ outside the set scanning angle range θ. In addition, the arrangement relationship between the light projector 4 and the light receiver 5 is such that the laser pulse emitted from the light projector 4 in the state where the head is swung beyond the set scanning angle range θ is transmitted through the translucent window plate 2. Is adjusted so that the light is reflected by the inner surface and reaches the light receiver 5. Note that "adjusted" means
This means that the relative positional relationship between the light emitter 4 and the light receiver 5 is adjusted in the front-rear and left-right directions.
Since the reflected beam 9 emitted from the light projector 4 and reflected on the inner surface of the translucent window plate 2 reaches the light receiver 5 without any adjustment, no special positional relationship adjustment is performed. .
That is, according to the study of the present inventors, a reception pulse train caused by such internal reflection exists in a time zone outside the scanning angle range θ in the output signal output in time series from the light receiver. Therefore, in this embodiment, such a received pulse train is positively used for diagnosis of the light emitting and receiving device. The important point here is that the reflected light from the front object arrives at the light receiver 5 only when there is some obstacle (vehicle, etc.) in the front sector warning area defined by the scanning angle range θ. Is limited to Δθ.
In the expanded state, the reflected light arriving at the light receiver 5 is limited to the reflected beam 9 based on the internal reflection, and the reflected light from the front obstacle reaches the light receiver 5 at the same time as the internal reflected beam 9. Is not. Therefore, the light receiver 5
By extracting the time zone corresponding to the scanning angle range θ and the time zone corresponding to the additional swing range Δθ in the signal output in time series from Can be reliably detected.

According to the second embodiment,
The light receiving element 6 and the light emitting element 7 in the conventional configuration shown in FIG. 1 are not required at all, and do not obstruct the front view of the projector 4 and the light receiver 5 at all. In addition, since the elements 6 and 7 are not required, the cost of the scanning laser radar device can be reduced.

Next, based on the configuration of the head unit shown in FIG. 2, automatic adjustment of the laser pulse intensity and operation diagnosis of the light emitting and receiving device are performed while realizing a constant headway control system using the head unit. An example will be described in detail with reference to FIGS.

FIG. 3 is a block diagram schematically showing an electrical configuration required for realizing this kind of constant headway control system. In the figure, an LD light emitting circuit 4a and a motor scan drive circuit 4b are built in the light projector 4. The LD light emitting circuit 4a functions as a drive circuit for driving the laser diode LD with a light emitting timing and light emitting power specified by a light emitting signal S1 supplied from the outside. The motor scan drive circuit 4b receives a start / stop signal S2 supplied from the outside and functions as a drive circuit that scans and drives a motor that rotates the laser pulse reflecting mirror. Has a built-in angle sensor for detecting the projection direction (angle) of the laser pulse at each point in time, and this angle sensor outputs an angle signal S3 to the outside.

The light receiver 5 has a PD light receiving circuit 5a built therein. The PD light receiving circuit 5a receives a light receiving signal S photoelectrically converted by a photodiode PD built in the light receiving device 5.
4 is sent out.

The CPU 10 comprises a so-called one-chip microcomputer or the like.
The light emission power signal S5 and the light emission timing signal S
6 are output, and these signals S5 and S6 are supplied to the light emission power adjustment circuit 11.

The light emission power adjustment circuit 11 generates a light emission signal S1 based on the signals S5 and S6, and supplies the light emission signal S1 to the LD light emission circuit 4a in the light projector 4 as described above. As a result, the light emission timing and light emission intensity of the laser diode LD are determined.

On the other hand, the light receiving signal S4 obtained from the PD light receiving circuit 5a is supplied to the A / D conversion circuit 12. A /
In the D conversion circuit 12, the light receiving signal S4 is branched into two systems,
One of them is appropriately shaped and supplied as a light receiving signal S4 'to the signal processing circuit 13, while the other is subjected to A / D conversion and then converted to a light emitting power signal S7 as a light emitting power signal S7.
Supply to PU10. In the CPU 10, the laser diode LD in the projector 4 is
Is used for servo control of the laser diode light emission intensity described later.

The signal processing circuit 13 detects the time difference between the light emission timing and the light reception timing in cooperation with the CPU 10. That is, the light emission timing is managed by the CPU 10, and the light reception timing is controlled by the A / D conversion circuit 1.
2 is detected based on the light receiving signal S4 'obtained from the second signal.
Then, the output signal S8 representing the time difference obtained in this way is supplied to the distance calculating means 14 constituted by another microcomputer or the like.

In the distance calculating means 14, the signal processing circuit 13
Using the light emitting / receiving time difference defined by the output signal S8 supplied from the camera, the emitting angle of the laser pulse at that time, and the relative positional relationship between the light emitting and receiving devices. The distance to the object is calculated, and the calculated distance is supplied as an output signal S9 to the constant distance control means 15 constituted by another microcomputer or the like.

The constant headway control means 15 outputs the ideal headway distance determined by the vehicle speed at that time and the output signal S9.
Based on the actual inter-vehicle distance determined from the above, servo control is performed so as to bring the actual inter-vehicle distance closer to the ideal inter-vehicle distance by automatically controlling the accelerator and the brake.

Since the basic structure of the above-mentioned constant distance control system is well known in various documents,
A more specific description will be omitted as it is understood by those skilled in the art.

Next, the servo control processing of the laser pulse intensity and the countermeasure processing when the laser pulse intensity is abnormal performed in the inter-vehicle distance control system will be described in detail with reference to the flowchart of FIG. 4 and the timing chart of FIG. .

As shown in FIGS. 4 and 5, in a state where it is determined that a laser scanning section (in this example, 50 ms) corresponding to the scanning angle range θ is determined based on the above-described angle signal S3 (step S1). 403 NO), while the CPU 6 outputs the above-described start / stop signal S2 to scan and drive the motor (step 401), the minute time interval (32 μs in this example) corresponding to the designed resolution.
Output the light emission timing signal S6. And
At the timing specified by the light emission timing signal S6, the laser diode LD is driven to emit light, and a laser pulse is emitted to the front sector warning area defined by the scanning angle range θ. The emitted laser pulse is reflected by the obstacle ahead of the vehicle and reaches the photodiode PD constituting the light receiver 5. As a result, in the light receiving signal S4 output from the PD light receiving circuit 5a, the pulses P1, P2 to P2 having a level corresponding to the distance to the front obstacle are included.
Pn appears, and as described above, the light emission timing signal S6
The constant vehicle-to-vehicle distance control is performed based on the time difference between the signal and the light receiving signal S4 '.

On the other hand, if it is determined based on the angle signal S3 that the light projection direction is out of the section corresponding to the angle range Δθ (step 403 YES), the light reception signal S4 contains the internal reflected beam 9 Corresponding reception pulses TP1, T
P2 and TP3 appear. For convenience of explanation, these pulses TP1, TP2, TP3 are shown to have a large level difference, but the levels of these pulses actually appearing in the same cycle are almost the same. Would.

On the other hand, outside such a section (step 403 YES), the CPU 6 sets the light emission power signal S
7, the levels of the pulses TP1, TP2, and TP3 are monitored (step 405). That is, the upper threshold value TH1 and the lower threshold value TH2 are prepared in advance for this level monitoring, and the pulse level detected by the projection power signal S7 is determined by the threshold values TH1 and TH2.
Predetermined servo control is performed depending on whether it is within the range of TH2 or outside of the range.

The level of the pulse TP1 is the upper and lower threshold T
H1 and TH2, and in this case, no special adjustment is made to the light emission intensity in the LD light emitting circuit 4a (step 405 NO).

On the other hand, as shown by the pulse TP2, when it is determined that the light emission power of the laser diode LD is small based on the light projection power signal S7 (step 405 YES), the content of the light emission power signal S5 becomes The light emission intensity of the laser diode LD is increased, and the light emission intensity of the laser diode LD is increased in response to the light emission signal S1 generated by the light emission power adjustment circuit 11.

On the other hand, as shown by the pulse TP3, when it is determined that the light emission intensity of the laser diode LD is high based on the light projection power signal S7 (step 405 YES), the light emission power signal S5 The contents will reduce the emission intensity of the laser diode LD,
Upon receiving the light emission signal S1 generated by the light emission power adjustment circuit 11, the light emission intensity of the laser diode is reduced.

The important point here is that the light projecting / receiving path from the light projecting device 4 to the light receiving device 5 via the internal reflection path 9 is always a constant value irrespective of the forward object.
The value of 7 is a point that accurately reflects the emission intensity of the laser diode LD constituting the light projector 4. Therefore, based on the light emission power signal S7, the laser diode LD
By servo-controlling the emission intensity of the laser diode, the intensity of the laser pulse emitted from the laser diode LD can always be maintained at an appropriate value.

On the other hand, if the state outside the power range is continued even if the state in which the scanning angle range θ is repeatedly scanned once in the cycle continues N times (YES in step 405).
406 YES), since there is a possibility that some abnormality has occurred in the light emitting and receiving system, a predetermined abnormal output signal is generated from the CPU 6, whereby the constant headway control system is forcibly stopped (step 408).

As described above, in this fixed distance control system, the output signal S4 of the light receiver 5 is monitored, so that the light transmitter 4 can be used during the idle time (outside the section) of the forward object guard.
Condition can be diagnosed.

In the above embodiment, the fixed headway distance control system is configured on the premise of the configuration of the head unit shown in FIG. 2. However, the same applies to the configuration of the head unit shown in FIG. A constant vehicle-to-vehicle control system, in which case, instead of the output of the light receiver 5,
If the output of the light receiving element 8 is monitored at a timing outside the same section, the emission intensity of the laser diode LD can be maintained at an appropriate value, or the system can be stopped by detecting an abnormality in the light emitting and receiving device.

Further, in the above embodiment, the laser light emitted from the laser diode LD is used as the pulse light in a state where the scanning angle range θ is exceeded. However, it is not necessary to perform the distance measurement during this time zone. Focusing on, this may be used as continuous light.

Further, in the above-described embodiment, the scanning laser radar device according to the present invention is employed in a constant headway control system in a vehicle. However, the scanning laser radar device according to the present invention is applicable to various other object detection applications. Of course, it can be applied.

[0055]

As described above in detail, according to the present invention, there is provided a scanning type laser radar apparatus which does not produce a blind spot in the front field of view due to the arrangement of the self-diagnosis element and can reduce the cost. There is an effect that it can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing a configuration of a head unit of a scanning laser radar device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram schematically showing a configuration of a head unit of a scanning laser radar device according to a second embodiment of the present invention.

FIG. 3 is a block diagram schematically showing an electrical configuration in a case where the scanning laser radar device based on the head unit shown in FIG. 2 is applied to an inter-vehicle distance control system.

FIG. 4 is a flowchart showing a configuration of a system program incorporated in CPU 6 in FIG.

FIG. 5 is a timing chart showing a relationship between a light emission timing signal and a light reception signal in the circuit configuration shown in FIG. 3;

FIG. 6 is a schematic diagram schematically showing a configuration of a head unit in a conventional scanning laser radar device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 front window 2 translucent window plate 3 housing 4 light emitter 5 light receiver 7 light emitting element 8 light receiving element 9 reflected beam reflected by light transmissive window plate 10 CPU 11 light emission power adjustment circuit 12 A / D conversion circuit 13 signal Processing circuit 14 Distance calculation means 15 Constant vehicle control means θ Scan angle range Δθ Angle range out of scan angle range S1 Light emission signal S2 Start / stop signal S3 Angle signal S4 Light reception signal S4 'Binarized light reception signal S5 Light emission power Signal S6 Light emission timing signal S7 Light emitting power signal S8 Output signal indicating light emitting / receiving time difference S9 Output signal indicating distance to obstacle

Claims (6)

[Claims] 1. A pair of light emitters and receivers are disposed side by side in a housing having a translucent window plate on a front window thereof, and the light emitters constituting the pair of light emitters and receivers are arranged in a horizontal direction. While oscillating the light emitting direction within the scanning angle range set in the above, the laser light is emitted to the front fan-shaped guard area through the translucent window plate, while the light receiving device constituting the pair of light emitting and receiving devices Is a scanning laser radar device configured to receive the reflected light of the laser pulse reflected by the front fan guard area through the translucent window plate, wherein a swing scanning range of the laser light emitted from the light emitter is provided. Is extended to outside the set scanning angle range, and the laser beam emitted from the projector in the state of swinging scanning beyond the set scanning angle range is the translucent window plate. Reflected at A light-receiving element is arranged at a position where the light-emitting element is reached, and by monitoring an output signal of the light-receiving element, it is configured to be able to diagnose the state of the projector at an idle time of the forward object guard. Scanning laser radar device. 2. A pair of light emitters and receivers are arranged side by side in a housing having a translucent window plate on a front window thereof, respectively, toward the front. While oscillating the light emitting direction within the scanning angle range set in the above, the laser light is emitted to the front fan-shaped guard area through the translucent window plate, while the light receiving device constituting the pair of light emitting and receiving devices Is a scanning laser radar device configured to receive the reflected light of the laser pulse reflected by the front sector guard area through the translucent window plate, wherein a swing scan of the laser light projected from the light projector is performed. The laser light emitted from the light projector in a state where the range is extended to outside the set scanning angle range and the head is swung beyond the set scanning angle range is the light transmitting window. On a board By adjusting the arrangement of the light emitting device and the light receiving device so as to reach the light receiving device after being radiated, and monitoring the output signal of the light receiving device, the idle time of the light emitting device in the idle time of the forward object guarding A scanning laser radar device characterized in that a condition can be diagnosed. 3. A servo control means for monitoring a level of an output signal of the light receiving element or the light receiving device and adjusting an intensity of a laser pulse emitted from the light emitting device so that the output signal always falls within a specified range. The scanning laser radar device according to claim 1, wherein the scanning laser radar device is provided. 4. An apparatus according to claim 3, further comprising an abnormality processing unit for issuing a predetermined abnormal output when the level of the output signal does not fall within a prescribed value due to the operation of the servo control unit. Scanning laser radar device. 5. A laser pulse emitted from the light emitter and reaching the light receiving element or the light receiver in a state in which the head is swung and scanned beyond the set scanning angle range, is transmitted through the light transmitting element. The scanning laser radar device according to any one of claims 1 to 4, wherein a mirror is provided at a reflection position where the light is reflected by the window plate. 6. The laser beam emitted from the projector in a state where the laser beam is swiveled beyond the set scanning angle range is continuous light or pulsed light. The scanning laser radar device according to claim 2.