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Such combination allow optical network builders test their fibers with different wavelengths at the same time. http://en.wikipedia.org/wiki/Optical_power_meter
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Two display units PM100
S122B Germanium Sensor (700-1800nm)
S120UV Silicon Sensor This model is: PM100 with sensors S120UV (200-1100nm) and S122B
Current Location: 36-228, 36-228 (There are two meters in the lab)
Vendor: Thorlabs
Manual: Instruction Manual
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