Light coupling structures for optical touch panels
US9389732B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 5, 2012 |
| Grant date | Jul 12, 2016 |
| Priority date | — |
| Expiry date | Oct 26, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04109
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A coupling element (14) for use in a touch-sensitive apparatus is arranged to transfer light between an electro-optical device (2) and a panel (4) for light transmission. The electro-optical device (2) is an emitter or a detector and has an operative solid angle given by orthogonal device divergence angles. The coupling element (14) is an optical component with a first light transmission surface (21) for facing the electro-optical device (2), and a second light transmission surface (22) for mounting on the panel (4). The coupling element (14) has an optical structure (23) that directs the light between the first and second light transmission surfaces (21, 22) by one or more reflections while expanding one device divergence angle (αx) into a component divergence angle at the second light transmission surface (22). Thereby, the component divergence angle defines a divergence (φp) in the plane of the panel (4) with respect to light propagating by internal reflections inside the light transmissive panel (4).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.