Patent ID: 8989536
Filing Date: 2015-03-24
Classification: B60K,G02B,G06F

Abstract:
1. A light-based user input device, comprising: a user input area; a printed circuit board; a plurality of light emitters mounted on said printed circuit board and arranged along a first edge of said user input area so as to be evenly spaced; a plurality of light receivers mounted on said printed circuit board and arranged along a second edge of said user input area, for receiving the light emitted by said light emitters and for generating outputs based on the amounts of received light; a curved lens arranged in front of said light emitters along the first edge, such that light emitted by each of said light emitters is refracted as it enters said curved lens, and is again refracted as it exits said curved lens, resulting in unevenly spaced collimated light exiting said curved lens and crossing said user input area to the second edge, the collimated light being shifted laterally by a non-zero offset along a direction parallel to the first edge, the offset being a characteristic of the arrangement of that light emitter vis-à-vis the curved lens; and a calculating unit connected to said printed circuit board for controlling said light emitters and said light receivers, and for determining location of an object inserted into said user input area from outputs of said light receivers, based on the values of the characteristic offsets of said light emitters.