Measuring system for contactless measuring the distance between a predetermined point of an object surface and a reference level

摘要

A system for measuring without contact the distance between a predetermined point of an object surface and a reference level using trigonometric principles includes a transmitting section with a source of radiation for emitting a plurality essentially parallel radiation beams of small separation to the point of the object surface to be investigated and a receiving section with a detector responsive to the reflected radiation. The detector converts the reflected radiation into a corresponding electrical signal and includes a radiation sensitive area which is restricted to a substantially linear area. The output of the detector is coupled to signal processing means in which a discriminating operation is carried out between detector signals which have, or have not, a predetermined separation or separations corresponding to the separation or separations between said radiation beams.