METHOD FOR OPERATING A LIDAR SYSTEM

A method for operating a LIDAR system with at least one spectrally tunable light source emitting a light beam having a temporally varying frequency and a transparent protective shield, arranged in a light path of the light beam, protecting the LIDAR system against environmental pollution includes determining distance values of an object based on beat frequencies of beat signals resulting from a superposition of partial signals obtained from partial reflection of the light beam at the object with reference signals not reflected at the object. Each distance value is determined from a peak in a signal spectrum obtained on the basis of a Fourier transformation of the beat signal. A degree of soiling of the protective shield is diagnosed by analyzing the signal spectrum in a predefined analysis frequency range. An upper limit frequency bounding said analysis frequency range is based on a distance of the protective shield.