| 摘要 |
PURPOSE:To facilitate the handling of a slide projector, an over-head projector, etc., by turning on an automatic focusing switch when an installation detection part detects a projection device being installed. CONSTITUTION:A projector 1 is positioned opposite a screen 14, one support member 6 is placed on an installation surface F, and the other support member 6 is put behind it. Consequently, a detection pin 7 turns on the automatic focus switch 4 and a lamp switch 5. Consequently, the contents of a projection body 24a are projected on the screen 14 by a lamp 20 through a projection lens 10. Further, a light emitting means 16 projects near infrared or infrared light on a point P2 on the screen 14 and a photodetection position detecting means 21 photodetects its reflected light, so that the projection lens 10 moves in the direction of the optical axis to perform focusing. Thus, an excellent projection image is obtained immediately at the time of the projection. |
