Automatically setting a threshold current for a laser diode.

摘要

A technique for automatically setting a threshold current for a laser diode (18) which has a linear laser operating region and a lower non-linear operating region. The laser diode (18) is controlled (1) during a warm-up period during which no operating current is supplied to the laser diode (18), to allow the electronics and laser diode (18) to stabilize; (2) during an initialization period, during which the current through the laser diode (18) is brought up to a threshold operating point above said non-linear operating region and during which no image data is applied to the laser diode (18); and (3) during an operating period in which digital image data is applied to the laser diode (18) to operate it in the linear laser operating region. <IMAGE>