JPH04351988A - Laser radar - Google Patents

Abstract

PURPOSE:To make detection of a linear obstacle easy by processing the distance information obtained by reflection of pulse laser light into signals, raising the directional information of the linear obstacle, and overlapping the information on the image of a camera tube. CONSTITUTION:A laser oscillation part 5 oscillates highly repeated and high output pulse laser light, sends to a scanning optical part 2 via a sending optical part 3, and scanning is carried out in the observation visible field of a camera tube 1 by the optical part 2. At that time, in the case that an object (an obstacle) which reflects the transmitted light exists, the reflection reception light is detected by a detecting part 6 through the optical part 2 and the reception optical part 4 and sent as a reception signal to an image processing part 7. The processing part 7 carries out space-differentiation of a laser radar image based on the distance data of the obstacle obtained by the time difference of the transmission and reception of light, raises the distance discontinuous directional data of the obstacle, and obtains the directional data of the linear obstacle. An image of the apparatus 1 is overlapped with it and displayed on the display part 8. The linear obstacle is easily distinguished in the image overlapped in this way.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser radar, and more particularly to a laser radar for detecting linear obstacles including overhead power lines.

0002

[Prior Art] Conventionally, obstacle recognition in this type of laser radar has been carried out using a CCD camera, an infrared imaging device (FLI), etc.
R, Forward Looking Infrastructure
This is done by an observer determining obstacles on an image taken by an imaging device such as -Red) or on a processed image.

0003

[Problems to be Solved by the Invention] The image obtained by the conventional laser radar described above is a passive image, so distance information to the obstacle cannot be obtained, and in the case of linear obstacles such as electric wires, the image is smaller than one pixel. In the case of a linear obstacle with a small diameter, the contrast ratio with the background pixels decreases, and the disadvantage is that the image of the linear obstacle cannot be recognized.

[0004] Furthermore, when there is a large temperature difference between a power transmission line and the background, it may be possible to recognize a linear obstacle in an image taken by an infrared imaging device, but depending on the contrast ratio with the background, the recognition of the image may be difficult. The disadvantage is that it is also difficult.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a laser radar which eliminates the above-mentioned drawbacks and which greatly facilitates the detection of linear obstacles.

[0006]

[Means for Solving the Problems] The laser radar of the present invention includes an imaging means for capturing an image of an observation field, and a device that transmits pulsed laser light and obtains direction information and distance information of an obstacle based on the received light. Obstacle information acquisition means and a laser radar image created based on the orientation information and distance information of the obstacle are spatially differentiated in the vertical direction by the distance information to separate linear obstacle data from the background,
and image display means for displaying a linear obstacle image including only the linear obstacles arranged in a linear manner, superimposed on the image of the observation field of view.

Furthermore, the laser radar of the present invention has a configuration in which the linear obstacle is an elevated electric wire.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

The embodiment shown in FIG. 1 uses C as an imaging means.
An imaging device 1 using a CD camera, a scanning optical section 2 constituting an obstacle information acquisition means for acquiring azimuth information and distance information regarding obstacles, a transmitting optical section 3, a receiving optical section 4,
It comprises a laser oscillation section 5, a detection section 6, and an image signal processing section 7 and a display section 8, which constitute an image display means for superimposing and displaying a linear obstacle on an image of the observation field taken by the imaging device 1.

Next, the operation of this embodiment will be explained.

[0012] The scanning optical section 2 scans the transmitted laser beam within the observation field of view. The transmission optical section 3 corrects the spread angle of the laser beam. The receiving optical section 4 focuses the received light on the detecting section 6, and the laser oscillating section 5 generates a high-repetition, high-output pulsed laser beam.

The laser oscillation unit 5 corrects the spread angle, etc. of the high-repetition, high-output pulsed laser beam generated based on the command from the image signal processing unit 7 in the transmission optical unit 3, and transmits it to the imaging device in the scanning optical unit 2. The observation field observed in step 1 is scanned in synchronization with the repetition of the pulsed laser beam in accordance with a command from the image signal processing section 7. At this time, an object (
If there is an obstacle), the reflected received light will pass through the scanning optical section 2.
Then, it is detected by the detection unit 6 which observes the same direction as the scanning direction of the transmitted light by the reception optical unit 4, and is taken into the image processing unit 7 as a reception signal.

The image processing unit 7 receives a transmission light generation timing signal, an azimuth signal indicating the scanning direction of the scanning optical unit 2, and
An image signal of the observation field by the imaging device 1 is captured, and the signal processing described below is performed.

FIG. 2 is an explanatory diagram showing an example of image processing in this embodiment. Figure 2(a) shows the original scene 10 in the observation field.
1 is shown. FIG. 2B shows obstacle azimuth information 102 indicating the position where the transmitted light is reflected by an obstacle within the observation field of view.

The distance information of the obstacle is obtained as the time difference between the generation timing signal of the transmitted light and the received light, as shown in FIG. 2(c).
Perform the signal processing (spatial differentiation) shown in . Although there are linear obstacles caused by elevated electric wires at positions A and B of the original scene 101 shown in FIG. 2(a), in the captured image 103 by the imaging device 1 shown in FIG. 2(c), Line-shaped obstacles cannot be recognized because the contrast ratio with the background is insufficient. Moreover, it is not possible to recognize whether the obstacle at position A is a background obstacle or a linear obstacle using only the obstacle orientation information 102 in FIG. 2(b). In this embodiment, as shown in FIG. 2C, spatial differentiation is performed using the distance information of the obstacle to highlight the obstacle orientation information A and B that are discontinuous with respect to distance. This spatial differentiation is performed on all the obstacle azimuth information to obtain linear obstacle azimuth information 105 shown in FIG. 2(d).

Image 103 captured by the imaging device 1 shown in FIG. 2(c) and linear obstacle orientation information 105 shown in FIG. 2(d)
The superimposed image 106 shown in FIG. 2(c) is created and displayed on the display unit 8. Line-shaped obstacles can be easily recognized in images that have been superimposed in this way.

[0018]

[Effects of the Invention] As explained above, the present invention obtains information on the direction of obstacles within the observation field by reflecting the transmitted light by pulsed laser light, so it is possible to obtain distance information on the obstacles at the same time. By performing signal processing such as spatially differentiating the obstacle orientation information using this distance information and highlighting the linear obstacle orientation information buried in the background obstacles, and superimposing it on the image taken by the imaging device, the imaging device This has the effect of making it much easier to recognize linear obstacles that could not be recognized using images.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of image signal processing in FIG. 1;

[Explanation of symbols]

1 Imaging device 2 Scanning optical section 3 Transmission optical section 4 Receiving optical section 5 Laser oscillation section 6 Detection part 7 Image signal processing section 8 Display section

Claims (2)

[Claims] Claim 1: an imaging means for capturing an image of the observation field; an obstacle information acquisition means for transmitting pulsed laser light and acquiring azimuth information and distance information of the obstacle based on the received light; A laser radar image created based on azimuth information and distance information is subjected to spatial differentiation using the distance information in the vertical direction to separate linear obstacle data from the background, and then only the linear obstacles arranged in a line are separated. 1. A laser radar comprising: image display means for superimposing and displaying a linear obstacle image including a linear obstacle image on an image of the observation field of view. 2. The laser radar according to claim 1, wherein the linear obstacle is an elevated electric wire.