JPS6360868B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an active image tracking device that three-dimensionally tracks a target by irradiating the target with laser light and obtaining target distance and angle information.

First, a conventional active image tracking device will be explained.

FIG. 1 is a block diagram showing a conventional active image tracking device. In FIG. 1, 1 is a laser oscillator, 2 is a zoom optical system for transmission, 3 is an imaging sensor, 4 is a distance measurement sensor, and 5 is a servo stand, 6 is the output light of the laser oscillator, 7 is the transmission laser beam,
8 is a target, 9 is a video signal, 10 is an image signal processor, 11 is an angular deviation signal, 12 is a distance signal, 13
14 is a tracking controller, and 14 is a servo motor. Further, FIG. 2 shows the relationship between the transmitted laser beam 7 at the position of the target 8 and the size of the cross section of the target 8 on the optical axis.

Next, the operation will be explained. laser oscillator 1,
The zoom optical system 2, the imaging sensor 3, and the distance measuring sensor 4 are mounted on a servo mount 5, and the servo mount has a structure that allows it to rotate and move up and down. Laser output light 6 from a laser oscillator 1 is irradiated onto a target 8 as a laser light 7 having an appropriate spread angle by a zoom optical system 2 for transmission. The reflected light from the target 8 is received by the imaging sensor 3 and the ranging sensor 4. A video signal 9 from the imaging sensor 3 is processed by an image signal processor 10 to obtain an angular deviation signal 11 of the target 8. The angular deviation signal 11 and distance signal 12 obtained in this way are input to the tracking controller 13, and the servo motors 14 (for turning and elevation) are respectively driven to direct the servo mount 5 in the direction of the target 8. Perform tracking.

Since the conventional active image tracking device is configured as described above, in order to uniformly irradiate the target 8 with the transmitting laser beam 7 having a Gaussian intensity distribution, the transmitting laser beam 7 must be placed at the position of the target 8. It must be sufficiently expanded than the target. On the other hand, regarding the distance measurement sensor 4, the larger the area occupied by the target 8 in the transmitted laser beam 7, the stronger the reflected light, and the farther the distance can be measured. In other words, the optimal spread angles of the transmitted laser light 7 corresponding to the imaging sensor 3 and the distance measurement sensor 4 are different, so in this method where the laser light spread is single as shown in FIG. The drawback was that the performance of the system could not be fully utilized.

This invention was made to eliminate these drawbacks, and uses a transmitting laser beam with a divergence angle suitable for each of the imaging sensor and the ranging sensor.
The present invention provides an active image tracking device that makes maximum use of the capabilities of each sensor.

An embodiment of the present invention shown in FIGS. 3 and 4 will be described below. In Figure 3, 1 is YAG
A laser oscillator, 2a, 2b, a beam optical system 3, an imaging sensor, 4 a ranging sensor, 5 a servo stand,
6 is the output light of the YAG laser, 7a and 7b are the transmitted laser beams, 8 is the target, 9 is the video signal, 10 is the image signal processor, 11 is the angular deviation signal, 12 is the distance signal, 13 is the tracking controller, 14 is a servo motor, 1
5 is a frequency multiplier, 16 is a spectrometer, 17a is a
17b is the fundamental wave of the YAG laser, and 18 is a mirror.

Further, FIG. 4 shows the relationship between the transmitted laser beams 7a and 7b at the position of the target 8 and the cross-sectional size of the target 8 on the optical axis.

Next, the operation will be explained in detail step by step. YAG
The output light 6 of the YAG laser oscillated by the laser oscillator 1 is input to a frequency multiplier 15, and a part of the laser light is converted into laser light with a double frequency. A spectroscope 16 separates this into a harmonic wave 17a and a fundamental wave 17b. The harmonic wave 17a is transmitted through the zoom optical system 2a so that the cross-sectional area of the transmitted laser beam 7a at the position of the target 8 is larger than that of the target 8, and is used for imaging. Fundamental wave number 17b is zoom optical system 2
b, the transmitted laser beam 7b is focused so that its cross-sectional area is smaller than the target 8, and is used for distance measurement. The mirror 18 converts the transmitted laser beam 7b into the transmitted laser beam 7.
Used to point in the same direction as a. The following operations are the same as the conventional one.

Although the above description has been made regarding the use of laser beams with different wavelengths that can be generated by a YAG laser, this invention is not limited to this, and can also be applied to the use of laser beams with different wavelengths, polarization directions, modulation methods, etc. that can be generated from various lasers. It can also be used in cases.

As described above, according to the present invention, a three-dimensional active image tracking device that utilizes laser light most efficiently is configured by dividing laser light into two and transmitting the beam at a beam divergence angle suitable for imaging and ranging. can do.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional three-dimensional active image tracking device, Fig. 2 is a diagram showing the relationship between the target and the cross-sectional size of the transmission beam in the conventional device, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a block diagram of a three-dimensional active image tracking device showing the relationship between the target and the cross-sectional size of the transmission beam in this invention. In the figure, 1 is a laser oscillator, 2, 2a, 2b are zoom optical systems, 3 is an imaging sensor, 4 is a distance measurement sensor, 5 is a servo mount, 6 is the output light of the laser oscillator, 7, 7a, 7b are transmitters Laser beam, 8 target, 9 video signal, 10 image signal processor, 1
1 is an angular deviation signal, 12 is a ranging signal, 13 is a tracking controller, 14 is a servo motor, 15 is a frequency multiplier, 16 is a spectrometer, 17a and 17b are YAG laser harmonics and fundamental wave, 18 is a mirror. It should be noted that the same or corresponding parts in the figures are indicated by the same reference numerals.

Claims (1)

[Claims] 1. A laser oscillator that oscillates a laser beam, a dividing means that divides the laser beam output from this laser oscillator into two laser beams for imaging and ranging, and a divergence angle of each of the two laser beams divided by the dividing means. a zoom optical system that can be adjusted according to the size and distance of the target, a laser transmitter that transmits laser light in the target direction, an imaging sensor and a ranging sensor that receive reflected light from the target. , an image signal processor that processes the video signal obtained by the imaging sensor to obtain an angular deviation signal of the target; and an angular deviation signal from the image signal processor and the angular deviation signal obtained by the ranging sensor. tracking control means for controlling a drive system to direct the laser transmitting means, the imaging sensor, and the ranging sensor in the target direction using the target distance signal; An active image tracking device characterized by realizing three-dimensional tracking by dividing the device into two parts.