Semiconductor optical device having a variable refractive index profile
US5126875A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 18, 1991 |
| Grant date | Jun 30, 1992 |
| Priority date | — |
| Expiry date | Jun 18, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A semiconductor optical device for focusing an optical beam includes a substrate doped to a first conductivity type, a semiconductor layer doped to a conductivity type different from that of the substrate, a recombination region formed between the substrate and the second semiconductor layer, a first electrode provided on a bottom surface of the substrate, and a second electrode provided on a top surface of the second semiconductor layer. The first electrode is transparent to the optical beam which passes freely therethrough. The second electrode is provided with a passage for the optical beam. The passage has a size which exceeds the carrier diffusion length in the semiconductor layer. A profile of refractive index is thus created in the recombination region such that the refractive index is at a minimum at the center of the circular passage and is at a maximum at an edge of the passage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.