公开(公告)号：GB2470553A

公开(公告)日：2010-12-01

申请号：GB0908899

申请日：2009-05-26

Applicant: ST MICROELECTRONICS LTD

Inventor： FINDLEY EWAN ,  BRODIE STUART

IPC: G06F3/042 ,  G06F3/0354

Abstract: A computer input optical navigation device has a radiation source capable of producing a beam of radiation; a sensor for receiving an image; and an optical element for identifying movement of the feature; wherein the optical element is formed from a single piece and includes at least one frustrated total internal reflection (F-TIR) surface. A further surface may be used to direct the reflections and beam to the sensor. The input surface may be convex, like a dome, with undulations to prevent scattered reflection. The optical element may be a plastics material such as poly methyl methacrylate (PMMA), polycarbonate, cycicyclophane copolymer). The illumination source may use a fly-eye, and the device may be used in mobile phones, remote controls or other applications requiring a small input mouse.