Optical for lighting reflector

Retro-reflectors can be used as target for PICOSCALE measurements. They reflect light anti-parallel with respect to the direction of incidence, whereas the orientation of the reflector plays a minor role. Thus, alignment of sensor heads to the target becomes very easy: The measurement beam must only hit the retro-reflector in the center and light will be reflected back into the sensor head so that the PICOSCALE can track the displacement. Furthermore, due to the very limited angular tolerance of a sensor head in combination with a plane mirror, retro-reflectors are often the only possibility to measure large angles.