Photodiode Power Sensors

Photodiode sensors have a high degree of linearity over a large range of light power levels: from fractions of a nanowatt to about 2 mW. Above that light level, corresponding to a current of about 1 mA, the sensor saturates and reads erroneously low. Therefore, most Ophir PD sensors have a built-in and removable attenuator allows measurement of up to 3 W without saturation.