Abstract: The invention relates to a miniaturized spectrometer for investigating the spectrum of emission radiation excited in an object by incident radiation. For the miniaturized spectrometer according to the invention, a diode laser is preferably used as an edge emitter (without a perforated shutter). The window of the edge emitter is arranged at the focal point of the converging lens at the input of the illuminating beam path (without an optical fiber), preferably without a perforated shutter. The edge emitter produces a divergent beam pencil with an elliptical cross-section. The length ratio of the main axes of the ellipse is more than 2:1. The large main axis of the ellipse runs parallel to the longitudinal axis of the entry slit of the microspectrometer.

Abstract: For investigating the spectrum of emission radiation excited in an object by incident radiation, miniaturised spectrometers are known for mobile use. These devices comprise a light source with perforated shutter, an illuminating beam path, a detecting beam path and a spectrometer. For the miniaturised spectrometer according to the invention, a diode laser is preferably used as an edge emitter (without a perforated shutter). The window of the edge emitter is arranged at the focal point of the converging lens at the input of the illuminating beam path (without an optical fibre), preferably without a perforated shutter. The edge emitter produces a divergent beam pencil with an elliptical cross-section. The length ratio of the main axes of the ellipse is more than 2:1. The large main axis of the ellipse runs parallel to the longitudinal axis of the entry slit of the microspectrometer. The miniaturised spectrometer has a reduced size and an increased sensitivity for emission radiation of low intensity.

Abstract: A measuring head (4) according to the invention comprises the combination of a zone lens (26), which is preferably a diffractive lens, with a hemispherical lens (23) or a GRIN lens (33). This represents a concept capable of miniaturization, resulting in very slender measuring heads (4) having a high numeric aperture and, accordingly, leads to the best resolution capacity. Such measuring heads are insensitive to angular errors as concerns the orientation of the measuring head to the surface to be measured or to an oblique positioning of the surface relative to the optical axis of the measuring head.