Fiber optic light traps for electro-optical display devices
US4344668A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1980 |
| Grant date | Aug 17, 1982 |
| Priority date | — |
| Expiry date | Mar 17, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/135
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In an electro-optical display device, a fiber optic faceplate which transmits light only through a well-defined solid angle, is optically coupled to an electro-optical display panel having a specularly reflecting surface. The display panel can be either an active device, such as laser diodes, or passive such as a dynamic scattering liquid crystal device. The axes of the optical fibers comprising the faceplate are slanted to the display surface at an angle such that the light which enters the front surface of the faceplate and is specularly reflected from the display surface is trapped within the faceplate. However, light emitted or scattered from on-state display elements is transmitted through the faceplate to the viewer. A high contrast display results because off-state display elements on the display surface appear dark under even intense ambient illumination whereas the on-state elements appear bright. The faceplate has two major opposing surfaces which are aligned to one another at a predetermined angle in order to control the size and direction of the display field of view.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.