Optical navigation device
AssigneeSTMicroelectronics (Research & Development) Limited
InventorsColin Campbell, Hazel McInnes, Ewan Findlay
Life of this patent
Estimating the term…
Abstract
An optical navigation device for use with mobile telephones and the like is disclosed, which has a reduced height as compared with current designs. The navigation device comprises a laser such as a VCSEL laser, an exposed user surface and two other surfaces that provide for total internal reflection of the incident laser beam. The surfaces are constructed with shallower than normal angles, preserving the basic functionality of the device while reducing the height.
Claims26
An optical navigation device comprising:
- a laser having a principal optical axis;
- an image sensor having an imaging surface;
- and
- an optical element having an exposed user surface, a first total internal reflection (TIR) surface, and a second TIR surface on an underside of the exposed user surface, wherein the optical element, laser and image sensor are together arranged to direct radiation emitted by the laser onto the imaging surface at least partly by total internal reflection by the first and second TIR surfaces, and wherein an angle between the principal optical axis of the laser and the first TIR surface is above 30° and below 40°.
6-11. (canceled)
13-15. (canceled)
23-26. (canceled)
A method of manufacturing an optical navigation device, the method comprising:
- arranging a laser, having a principal optical axis, emit radiation toward an optical element having an exposed user surface, a first total internal reflection (TIR) surface, and a second TIR surface on an underside of the exposed user surface, an angle between the principal optical axis of the laser and the first TIR surface being above 30° and below 40°;
- and
- arranging an image sensor, having an imaging surface, adjacent to the optical element, wherein
- arranging the laser and the image sensor includes arranging the optical element, laser and image sensor to direct the radiation emitted by the laser onto the imaging surface at least partly by total internal reflection by the first and second TIR surfaces.
A mobile communications device comprising:
- an optical navigation device that includes:
- a laser having a principal optical axis;
- an image sensor having an imaging surface;
- and
- an optical element having an exposed user surface, a first total internal reflection (TIR) surface, and a second TIR surface on an underside of the exposed user surface, wherein the optical element, laser and image sensor are together arranged to direct radiation emitted by the laser onto the imaging surface at least partly by total internal reflection by the first and second TIR surfaces, and wherein an angle between the principal optical axis of the laser and the first TIR surface is above 30° and below 40°.
A method, comprising:
- operating an optical navigation device including a laser having a principal optical axis;
- an image sensor having an imaging surface;
- and an optical element having an exposed user surface, a first total internal reflection (TIR) surface, and a second TIR surface on an underside of the exposed user surface, an angle between the principal optical axis of the laser and the first TIR surface being above 30° and below 40°, the operating including:
- totally internally reflecting radiation emitted by the laser by the first and second TIR surfaces;
- illuminating at least part of the imaging surface with at least part of the radiation totally internally reflected by the first and second TIR surfaces;
- bringing an object into contact with the exposed user surface to frustrate total internal reflection of at least a portion of the laser radiation at the second TIR surface;
- and
- deriving user input information from changes in sequential image frames detected at the imaging surface.
34-35. (canceled)
Dependencies are inferred from the claim text.