Tapered amplitude optical absorber for waveguide photodetectors and electro-absorption modulators
US6167172A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1999 |
| Grant date | Dec 26, 2000 |
| Priority date | — |
| Expiry date | Mar 5, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12126
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical waveguide device (30) that limits the peak optical intensity applied to an optical absorbing device (36), such as a photodetector or electro-absorption modulator. The optical waveguide device (30) includes a single mode input waveguide (34) coupled to a multi-mode, waveguide interference coupler (32). A single mode output waveguide (38) collects the light from the interference coupler (32). The absorbing device (36) is defined in the waveguide coupler (32) by a reverse-biased p-i-n diode structure. A voltage potential applied to the diode structure creates an electric field across the waveguide coupler (32) that causes the waveguide coupler (32) to absorb. Light entering the interference coupler (32) from the single mode waveguide (34) expands into other propagation modes that interact to constructively and destructively interfere. Because the light expands in the coupler (32), the amplitude of the light decreases even though the overall power remains substantially the same. When the light recombines as it approaches the output waveguide (38), the amplitude of the light returns to the input amplitude. The absorbing device (36) is defined in the waveguide coupler (32) bet…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.