| 摘要 |
The invention concerns an input device for screen navigation, such as cursor control on a computer screen, said input device comprising a housing, and optical detection means comprising at least one substantially coherent light source for detecting the movement of a surface, wherein the substantially coherent light source is positioned in the housing close to the detection surface illuminating at least a part of this surface, and at least one set of detector means for detection of relative displacement of the surface and the input device in at least one direction of movement by receiving the light emanating from the surface, wherein the optical detection means comprises an optical member including at least three optical elements for mapping of different specific first areas on the surface onto substantially the same second area on the surface thereby generating an oscillating optical signal from the surface movement in one of the first and second areas. Hereby, an inexpensive and compact input device is provided that has an optical detection system, which emits a low amount of radiation by slitting the emitted beam from the light source into at least three beams. <IMAGE> |
