| 摘要 |
PROBLEM TO BE SOLVED: To automatically adjust focus, a field angle, or a swing and tilt. SOLUTION: The lights modulated by liquid crystal panels 3R, 3G, and 3B are put together by an optical part 2 and projected on a screen through a focus lens 7 and a zoom lens 9. The light reflected by the screen as a range-finding image pattern light is projected passes through a slit 12 and is made incident on a line sensor 13. An MPU 14 finds the distance to the screen from the position of the reflected light on the line sensor 13. Then a focus actuator 8 is controlled according to the found distance to move the focus lens 7 so that the image on the screen is put in focus. |
