ELECTRO-OPTIC SYSTEM CONTROLLER

摘要

A method for calibrating a laser module system includes the processes of connecting testing equipment used for laser calibration to the laser output; setting preamplifier gain to nominal; connecting input of preamplifier to ground; turning off the DC bias for laser; canceling the offset voltage of the preamplifier; recording the monitoring photodiode dark current; incrementing the DC bias to the laser; reading PL; computing dPL/dIL; setting the DC bias to threshold; recording PLTH; recording the photodiode current IPT; recording the temperature of laser module; connecting the preamplifier to provide a VREF input signal to the laser module input increment preamplifier gain G1 while reading power output PL with instrument; determining the preamplifier gain GF needed to obtain full scale output of laser power (PLM); determining the corresponding photodiode current for above condition IPM; calculating the effective responsivity Reff of the module containing the laser and the photodiode; and storing the effective module responsivity Reff in memory.