Optical sub-carrier multiplex television transmission system using a linear laser diode
US5020049A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1989 |
| Grant date | May 28, 1991 |
| Priority date | — |
| Expiry date | Oct 13, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/2275
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An amplitude-modulated vestigial-sideband, television channel sub-carrier multiplexed optical fiber transmission system includes a laser diode operating linearly throughout the desired range of multiplex frequencies. Such linear laser diode operation is accomplished by limiting leakage current within the laser diode to a very low level. The composite second-order distortion in the optical output signal from the laser diode is down typically 50 db from the video carrier for each channel. For some laser diodes that exhibit slow turn-on in the L-I characteristic, there is a point of inflection in the L-I curve. Operation with the laser biased at or near this point results in extremely linear performance, even though the laser may have insufficient blocking of leakage current to otherwise produce acceptable linearity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.