Electro-optical device
US4790635A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 24, 1987 |
| Grant date | Dec 13, 1988 |
| Priority date | — |
| Expiry date | Apr 24, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/218
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electro-optical device is arranged as a Fabry Perot etalon comprising two mirrors and a central region. The mirrors are multilayer heterostructures of Al.sub.x Ga.sub.1-x As semiconductor materials where x alternates between 1.0 and 0.3. The central region may be a multiple quantum well structure of Al.sub.x Ga.sub.1-x As where x alternates between 0 and 0.3. The etalon material doping is non-uniform so that it is electrically a semiconductor device with a biasable central region. The optical path length in the central region is electric field dependent, and the etalon transmission or reflection is accordingly modulatable by varying the central region bias. The mirrors may be heavily doped and of opposite conductivity type with the central region undoped. This provides a PIN diode. Light incident on the etalon executes multiple transits of the central region. It is therefore unnecessary to employ long path lengths and high fields to enhance weak electro-optical effects in order to produce significant modulation, this being necessary in prior art devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.