With many applications it is essential to determine distances, e.g. the distance between two objects (gap size measurement) during a movement. The sensors of the A-LAS series or the SPECTRO-1-CONLAS series and the SPECTRO-2-CONLAS series perform very good services and can provide scan frequencies of up to 175 kHz. The measurement ranges are determined by the light spot size. Spot sizes from 0.1mm to 100mm are available.

Fibre optics cross-section converters can be used in potentially explosive atmospheres. The longitudinal axis of the right-angled cross-section determines the size of the measurement range. The SPECTRO-1-FIO and SPECTRO-2-FIO sensors are two quick versions for potentially explosive atmospheres with scanning frequencies up to 175 kHz or 130 kHz.