Optical sensor, e.g. for detecting liquids

摘要

The optical sensor contains a light source (12,13), a light receiver (14,15) and a light transmissive sensor body (11) with an optical boundary surface which either wholly, partly or mainly does not pass the light generated by the source acting in the manner of a medium outside the boundary surfaces.The arrangement is designed so that for the transition between the sensor body (11) to air (18) a part (20) of the light from the source is reflected to the receiver and the other part (21) is transmitted. A curved optical boundary surface is used in conjunction with a relatively broad light beam from the source.