Scanning instruments are becoming widely used in surveying applications due to their inherent ability to produce a detailed three dimensional image of an object or a scene, which can be evaluated later. They all need in addition to a scanning mechanism a thin laser beam for ranging to sample an array of measurement points by providing polar coordinates. The laser classification aspects of such an instrument, a Leica Scan Station C10, are presented.
Depending on the modes of operation of the scanner different laser safety limits apply. The average or pulse train criteria are the most restrictive ones and the single fault condition has to be evaluated, too. The benefits of treating the source as extended compared the simplified evaluation are discussed and the complexity of this approach is shown.