Patent ID: 9300397
Filing Date: 2016-03-29
CPC Classification: G01S,H04B

Claim Text:
1. A device for measuring an optical transmission path wherein: at least one optical transmitter transmits into at least a first transmission path; at least one object that is not part of the device and which is located at an end of the first optical transmission path is able to reflect light into at least one second optical transmission path that is terminated with at least one receiver; the receiver is able to receive at least one transmitter signal of the optical transmitter after modification by passage through the first optical transmission path and/or the second optical transmission path and/or by reflection on the object and convert the at least one transmitter signal into at least one receiver output signal; a controller includes at least one controller output that outputs a controller output signal that can be used outside of the device; the controller constructs a compensation signal and/or the transmitter signal based on the receiver output signal; the controller output signal represents a representative measured value for at least one property of the first transmission path or said second optical transmission path or a representative measured valued for at least one property of the object and the controller output signal issues the representative measured value at least upon request; a compensation transmitter transmits into at least a third transmission line; the third transmission line ends at the receiver; the receiver receives at least the compensation signal of the compensation transmitter superimposed with the transmitter signal; the controller controls the compensation transmitter and/or the optical transmitter so that the receiver output signal contains no more components of the transmitted signal and/or contains no portions of the compensation signal except a control error and system noise; an optical receiver path filter is part of the device and is part of at least one second optical transmission path; the optical receiver path filter has a transmissivity for the wavelength of the light of the optical transmitter and/or for the wavelength of the light to be detected of at least 50%, or better 75%, or better 88%, or better 95%, or better 98%, or better 99%; the optical receiver path filter has a transmissivity for the wavelength of the light of the compensation transmitter of at most 50%, or better at most 25%, or better at most 12%, or better at most 5%, or better at most 2%, or better at most 1%; the optical receiver path filter has an absorption factor for the wavelength of the light of the compensation transmitter of at least 25%, or better at least 50%, or better at least 75%, or better at least 88%, or better at least 95%, or better at least 98%, or better at least 99%; the compensation transmitter and at least one receiver are separated by a nose-piece so that a direct illumination of the receiver by the compensation transmitter is not possible; the compensation transmitter is placed in a first cavity and in which the nose-piece is part of the wall of the first cavity; the receiver is placed in a second cavity and in which the nose-piece is part of the wall of the second cavity; the receiver and the compensation transmitter are connected by at least one compensation optical path that is able to transmit light by at least one reflection at a reflector from the compensation transmitter onto the receiver; the optical transmitter and the receiver are separated by at least one nose piece such that a direct illumination of the receiver by the optical transmitter is not possible; the optical transmitter and the receiver are optically separated by at least one optical barrier; the device possesses at least one absorber that prevents the emission of light of at least the compensation transmitter in at least one predefined direction and/or in a direction toward at least one object (O) to be measured; and the optical transmitter and the compensation transmitter of the device transmit with different center wavelengths.