Patent ID: 9476828
Filing Date: 2016-10-25
CPC Classification: G01N,G01S,G02B

Claim Text:
1. An optoelectronic sensor ( 10 ) having a circumferential front screen ( 42 ) comprising a curvature both in a circumferential direction and in a height direction transverse to the circumferential direction and thus having a circumferential focus area ( 46 ) in which light reflected at the inside of the circumferential front screen ( 42 ) is focused, wherein a plurality of test light transmitters ( 50 a - f ) located on a first side of the front screen ( 42 ), at least one reflector ( 52 a - f ), and at least one test light receiver ( 56 a - b ) form a test light path ( 54 a - f ) on which test light passes from the test light transmitter ( 50 a - f ) through the front screen ( 42 ) to the reflector ( 52 a - f ) and subsequently onto the test light receiver ( 56 a - b ), and wherein an evaluation unit ( 36 ) is provided which is configured to detect a decreasing light transmissivity of the front screen ( 42 ) based on a decrease of a signal generated by the test light in the test light receiver ( 56 a - b ), characterized in that the test light receiver ( 56 a - b ) and the reflector ( 52 a - f ) are arranged on a second side of the front screen ( 42 ) opposing the first side of the front screen ( 42 ) such that the test light path ( 54 a - f ) leads from the reflector ( 52 a - f ) via a reflection on the inside of the front screen ( 42 ) to the test light receiver ( 56 a - b ), wherein the test light path ( 54 a - f ) of the plurality of test light transmitters ( 50 a - f ) share a common test light receiver ( 56 a - b ).