| 摘要 |
PURPOSE:To provide information contained in an original in a short time and to detect the original in any arbitrary size by irradiating the surface of the original with light emitted from a while light source through the light transmis sion part of liquid crystal and detecting scattered light. CONSTITUTION:As a white light source 1, a while fluoscent lamp is used and on that lamp, liquid crystal 2 is arranged so as to surround it. One part of the white light source 1 emits light through a light transmissive picture element (window) 3 on the liquid crystal 2, and the window 3 is made movable. Namely, the entire liquid crystal 2 looks black on the appearance but one part is made bright and that is moved. Light emitted from this movable window 3 is moved on an original 7 together with the move of the window 3 and scattered on the original 7. Such scattered light 6 is monitored by a photodetector 8. On the other hand, the edge of the original 7 is detected by the increase/decrease of scattered light 7 and from the relation with the position of the window 3, the side of the original 7 can be provided. |
