Optical power meter Pulse power measurement
Optical power meters usually display time averaged power. So for pulse measurements, the signal duty cycle must be known to calculate the peak power value. However, the instantaneous peak power must be less than the maximum meter reading, or the detector may saturate, resulting in a wrong average readings. Also, at low pulse repetition rates, some meters with data or tone detection may produce improper or no readings.
A class of "high power" meters has some type of optical attenuating element in front of the detector, typically allowing about a 20 dB increase in maximum power reading. Above this level, an entirely different class of "laser power meter" instrument is used, usually based on thermal detection.
August 12, 2011