Laser diode modulator

USH436H · kind H · statutory invention registration

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventors

• Walter E. Milberger · Severna Park, US
• Charles S. Kerfoot · Pasadena, US

Key dates

• Grant date: Feb 2, 1988

Classification

• Technology area (CPC —): General

Abstract

A low voltage trigger pulse is coupled to a three-stage driver which genees therefrom a high amplitude (e.g., 20 amp.) decaying current spike of predetermined width. The current pulse or spike from the driver is coupled to the gates of a multiplicity (i.e., 12) of parallel-connected field effect transistors (FETs) to turn or switch the same to the "ON" state. A laser diode array is series-connected with the parallel connected FETs so that when the latter is switched ON a very high (100 amp.) current pulse is delivered to the laser diode array to enable the same. At the cessation of the pulser current drive, a passive pull-down technique is used to enhance the turn-off of the parallel-connected FETs so that the laser diode array is quickly disabled. A protective overload circuit sets a limit to the average current through the laser diode array without affecting the pulse burst current.