Noise from grounding, the cable capacitance, temperature effects, stray and am-bient light and detector noise are interfering the measurement. This impact is the higher, the lower to measured optical power. Thorlabs' power meter consoles have the ability to recognize the connected sensor type as well as its responsivity. The measured. PM100USB 1 General Information The PM100USB Optical Power and Energy Meter measures the optical power of laser light or other monochromatic or near monochromatic light, detected by an appropriate sensor and is compatible with all Thorlabs “C-Series” Photodiodes, Thermal Sensors, Pyroelectrics. fic information on the PM100USB handheld optical power and energy meter. A general des ription is followed by explanations of how to operate the unit manually. I was wondering if anyone encountered this issue: We are trying to measure diffraction efficiency of a blaze grating with a beam with an NA of around 0.
