Abstract: A transmitting and receiving arrangement for fiber-optic sensors includes a first radiation source L1 having radiation which is conducted via an optical switch having a wavelength-dependent transmission or reflection filter into the fiber FA going to the sensor head. The radiation returning from the fiber is conducted via the optical switch to a first detector D1. The arrangement further includes: a second detector D2 which is permanently optically coupled into the radiation path of the first radiation source L1; and, a second radiation source L2, which is switched on alternately to the first radiation source L1 and both detectors D1, D2 are subjected to the radiation of this radiation source.

Abstract: The invention is directed to an optical switch for a sensor. The optical switch conducts radiation emitted from a radiation source into a fiber leading to the sensor and conducts radiation returning from this fiber onto an optoelectric receiver. The optical switch includes a filter having wavelength-dependent transmission and reflection characteristics as well as optical components for collimating or focusing. The optical components together with the filter define a component unit in the form of an acute angle optical switch. The optical switch also has a first beam splitter mounted downstream of the component for collimating the radiation emitted by the radiation source. The beam splitter splits off a component of the radiation emitted by the radiation source as a reference beam and the reference beam is guided via deflecting prisms and spacers to a second beam splitter.