| 摘要 |
PURPOSE: A device and a method for adjusting focus of an over head projector are provided to automatically adjust a focus distance and to obtain correct and exact image on a screen surface by automatically controlling a height of a reflection mirror using an actuator and lifting means to make an optical axis be at right angles on the screen surface. CONSTITUTION: A device for adjusting focus of the over head projector includes distance sensing parts(20a,20b,20c,20d) for sensing a distance between a reflection mirror(13) and a screen surface, a driving motor(M) mounted at a body(1), a lifting part receiving the driving force from the driving motor and moving a head(14) up and down, and a controlling part receiving signal of the distance between the reflection mirror and the screen surface sensed by the distance sensing part and outputting signal for driving the driving motor. |
