Abstract: An arrangement for measuring intraocular distances between different optical boundary surfaces of the human eye by at least one interferometric measurement system is provided. The arrangement further comprises at least one diffractive optical element (DOE) for dividing the illumination beam path into partial beam paths for different boundary surfaces and/or for combination and mutual adaptation of the wavefronts of measurement light components proceeding from different boundary surfaces and/or for adaptation of the wavefronts of measurement light components proceeding from different boundary surfaces of the eye to the wavefront of the measurement light of at least one interferometric reference arm.

Abstract: An optical scanning apparatus for scanning an array of sample regions carried on the surface of a substrate is disclosed. The apparatus includes a beam generator for generating a light beam effective to produce detectable light from such sample regions, and scanning optics for scanning the beam in one direction corresponding to a linear array of such sample regions. Light emitted from the linear array is imaged through an imaging system whose optical axis is angularly offset from the optical axis of the illumination beam, onto a photodetector. The optical configuration achieves high performance with relatively simple optics.

Abstract: The invention is directed to an arrangement for operating a laser diode. A two-stage stabilization circuit is provided for stabilizing the wavelength of a laser diode to exactly defined values for its use in distance measuring interferometers. In addition to presetting the operating parameters of current and temperature of the laser diode, the emitted wavelength of the laser diode is controlled to a predetermined transmission maximum of a Fabry-Perot interferometer. At switch-on, a control program can be called up and compute new values for the operating parameters premised on the last measured values of the operating parameters and initially determined and stored coefficients. In this way, the program always reliably sets the wavelength of the laser diode to the same transmission maximum.

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.

Abstract: The injection current for a laser diode is modulated so that a pregiven coherence function is obtained which drops off continuously at both ends outside of the coherence length. Several laser diodes are used for a very short coherence length for which the modulated wave numbers of the emitted radiation follow one another or overlap.