Laser diodes are extremely sensitive to electrostatic discharge, excessive current levels, and current spikes (transients). If an excessive current flows in a laser diode, a large optical output is generated occur and the emitting facet may be damaged. This optical damage can happen even with a momentary over-current. There are devices you can retrofit to make your laser diode impervious to static. The main causes of undesirable surge energy are static electricity on the human body, shipping containers made of unsuitable materials, abnormal pulses generated from test equipment, and voltage. The release of such charges causes an instantaneous flow of electric current (“Electrostatic discharge (ESD)”).
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