Compensation for an optical sensor via a printed circuit board

摘要

Opto-electronic measuring arrangement which is largely independent of extraneous light, comprising emitted and compensation light sources, which emit light time-sequentially and in a phased manner, wherein the emitted light is phase-shifted respectively by 180°. An optical receiver receives the light emitted by the emitted light source and reflected by the object being measured together with the light from the compensation light source. The actuation signals for the emitted and compensation light sources are controlled such that the synchronous signal difference occurring in the receiver between the different phases is reduced to zero. The optical coupling between the compensation light source and the receiver diode occurs mainly via an optical system in a printed circuit board on which the compensation light source and the receiver are arranged. The printed circuit board itself, i.e. the FR4 component thereof, may constitute the optical conductor between the compensation light source and receiver diode.

主权项

1. An opto-electronic measuring arrangement, comprising:
a transmitter, a compensation transmitter, and a receiver for measuring the transmission properties of a first transmission path between the transmitter and the receiver, wherein:
the transmitter emits an emission signal along the first transmission path, the emission signal being detected by the receiver after the emission signal has traversed at least a part of the first transmission path;the compensation transmitter emits a compensation signal along a second transmission path, the compensation signal being detected by the receiver after the compensation signal has completed the second transmission path; andthe receiver is configured to superimpose the emission signal and the compensation signal in a linear manner and to form a receiver output signal therefrom; and a control unit that generates a compensation control signal from the receiver output signal for actuating the compensation transmitter and/or a transmitter control signal for actuating the transmitter for feedback-controlled adjustment of the receiver output signal such that the receiver output signal remains substantially unchanged if the transmission properties of the first transmission path are changed; wherein coupling of optical signals between the compensation transmitter and the receiver is performed at least partially via an optical system in a printed circuit board on which the compensation transmitter and the receiver are arranged.