Optical waveguide system for a flat-panel display
US6326939A · kind A · utility
Inventor
Key dates
| Filing date | Sep 24, 1999 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Sep 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A flat display for providing high contrast, low-artifact enlarged optical images. The flat panel display comprises a pixelated input imaging device, a first array of optical waveguides including a bias cut, a first light redirecting layer, a second array of optical waveguides also including a bias cut, and a second light redirecting layer. The first and second arrays of optical waveguides enlarge an input image in first and second directions, respectively. Moire fringe effects are minimized by one or more of: forming the waveguides of the first and second arrays such that the ratio between the waveguide size of the first array to the waveguide size of the second array is at least 1.25; forming a random distribution of waveguides sizes in the first and second arrays; and tilting the second array with respect to the first array. A ratio between the major dimension of the pixels of the input imaging device and the major equivalent dimension of waveguides is between about 1.20 to 4.0. This particular spatial frequency relationship typically yields a modulation transfer function of between 0.2 and 0.95 at the highest spatial frequency supported by the input imaging device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.