Distance measuring device using reflection of light - has remote light source and photodetector coupled to measuring head via optical fibres

摘要

The device provides the distance of a measuring object from a fixed reference plane. It comprises a light source used to provide a light marking on the measuring object and a photodetector receiving the reflected light coupled to an electronic evaluation circuit. The light source and the photodetector are both coupled to a measuring head containing an optical imaging system via respective optical fibres. Pref. the measuring head has an angled focussing lens receiving the light from the source via the optical fibre and forming a light spot on the measuring object. The reflected light is received by a second lens parallel to the surface of the measuring object with a number of spaced optical fibres on the opposite side of the lens leading to the photodetector. The device can be used for extrusion moulded metal rods or rails.