| 摘要 |
PURPOSE:To select automatically optimum fine or coarse servo tracking and to track a target excellently all the time, by receiving reflected light from the target, monitoring the tracking state, and switching the coarse sevo tracking to fine servo tracking different in visual field. CONSTITUTION:The light wave sensor 3a of the rough tracking system 11 equipped with a receiving optical part 2a having wide visual field photodetects reflected light from the target, and a picture signal processor 6a outputs an error in the azimuth and elevation components of the optical axis of the optical system against a target direction to perform servocontrol over a servo driving frame control part 8 and a servo driving frame, tracking the target coarsely. At the same time, an in-screen target tracking condition monitor part 13a which responds to the output of the processor 6a monitors the tracking state of the target. A fine tracking system 12 equipped with a narrow- visual-field receiving optical part 2b, in-screen target tracking condition monitor part 13b, etc., is the same as above-mentioned, and a fine/coarse switching part 15 is controlled according to the monitored result of the monitor part 13a or 13b to select the optimum fine or coarse tracking according to the tracking state, tracking the target successively and excellent all the time without any intermittence. |
