Apparatus and method for optically transmitting electrical signals in the 20-300 gigahertz frequency range
US5631916A · kind A · utility
Inventors
Key dates
| Filing date | May 1, 1995 |
| Grant date | May 20, 1997 |
| Priority date | — |
| Expiry date | May 1, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/0625
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention discloses a method and an apparatus for optically transmitting a narrow-band optical signal beam having a sub-carrier frequency in the 20 to 300 GHz range. The apparatus has a semiconductor laser with a lasing cavity of length L. The length L preferably ranges from less than 1 mm to 10 mm, thereby defining the round-trip resonance frequency according to the following equation c/2 nL. The apparatus has a signal source for generating an electrical modulating signal having a modulation frequency contained in a narrow band containing the round-trip resonance frequency. An in-coupling means delivers the electrical modulating signal to the semiconductor laser which produces a sub-carrier modulated signal beam whose sub-carrier modulation frequency lies within a response band and corresponds to the modulation frequency. The apparatus further includes a biasing device for providing a biasing voltage for tuning the response band and the sub-carrier modulated signal beam. According to the method of the invention the biasing voltage is used to set the width of the response band and to set a phase shift in the sub-carrier modulated optical signal beam. Varying the biasing voltage…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.