A new use of micro-optical systems are temperature scanners, those according to the current angle position of the reflector working in resonance, the radiant heat of a certain point of the item under test on the detector. By a purposeful deflection one obtains a line scan over the object which can be measured. With movement of the object which can be measured perpendicularly to the scan axis (e.g. goods course) it is also possible to detect the planar temperature distribution. Thus uses of the simple temperature monitoring are realizable during technological processes up to the production more high-dissolved (locally and temporally) temperature distributions. Beside the flexible, application-oriented parameterization of scan rate, scan angle, optics and reflector a complimentary, durable and above all user-friendly employment is intended.