Drive and control circuit for laser diode
US4807239A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 1, 1987 |
| Grant date | Feb 21, 1989 |
| Priority date | — |
| Expiry date | Apr 1, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/04113
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A drive and control circuit for laser diodes includes: a first switching element connected in series to a laser diode connected to a constant-current source for actuating the laser diode when a binary drive signal is at one level thereof; an impedance element connected in parallel to the series circuit of the laser diode and the first switching element, the impedance element being connected to receive the constant-current source together with the laser diode and having impedance characteristics substantially equal to those of the laser diode and the constant-current source; an integrator circuit for integrating the data at the one level; an impedance control circuit for variably controlling the impedance of the impedance element in response to the integrator circuit; and a second switching element connected in series to the impedance element for actuating the impedance element when the drive signal is at the other level. Furthermore, an alternative embodiment of the drive and control circuit includes the combination of a comparator, an integrator circuit, a constant-current circuit, a counter and a timer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.