Abstract: This relates to an optical system for detecting radiation from a measuring area, comprising at least one radiation source for generating radiation along an excitation beam path which guides radiation from the radiation source to the measuring area, and comprising a detection beam path which guides radiation from the measuring area to at least a first and a second detector, wherein along the detection beam path, exactly one tube lens having a first end and an opposite second end, a first beam splitter, a first detector in the reflection direction of the first beam splitter, and a second detector in the transmission direction of the first beam splitter are arranged in succession, wherein the first detector has a first detection surface and the second detector has a second detection surface which is spaced from the first detection surface, and the first and second detection surfaces are arranged along the detection beam path at the same distance from the second end of the tube lens.

Abstract: This relates to an optical system for detecting radiation from a measuring area, comprising at least one radiation source for generating radiation along an excitation beam path which guides radiation from the radiation source to the measuring area, and comprising a detection beam path which guides radiation from the measuring area to at least a first and a second detector, wherein along the detection beam path, exactly one tube lens having a first end and an opposite second end, a first beam splitter, a first detector in the reflection direction of the first beam splitter, and a second detector in the transmission direction of the first beam splitter are arranged in succession, wherein the first detector has a first detection surface and the second detector has a second detection surface which is spaced from the first detection surface, and the first and second detection surfaces are arranged along the detection beam path at the same distance from the second end of the tube lens.

Abstract: The invention relates to a method for the thermal treatment of a surface layer (4) on a semiconductor substrate (5). Laser pulses (2) generated by a laser (1) are emitted onto the surface layer (4). This method can be used to produce, in particular, ohmic contacts to III-V compound semiconductors.

Abstract: Apparatus for controlled ablation of material from a predetermined working point, comprising a first laser, in particular excimer laser, for generating laser radiation pulses having a wavelength in a wavelength range suitable for the ablation, in particular in the ultraviolet spectral range, further comprising a radiation analyzer such as a spectrometer for analysis of material-specific radiation from the ablation plume forming at the working point, and a second laser, in particular a tunable dye laser, for generating a further laser radiation in a wavelength range which is different from said first wavelength range and which is better suited for the resonant stimulation of the radiation serving for the analysis than the ablation radiation wavelength range.