[Determination of the energy density of rapid periodic laser light patterns of homogeneous superficial coverage for medical applications].

The use of laser light in in vitro experiments on fibroblasts and osteoblasts and animal experiments has revealed similar thresholds the crossing of which is apparently necessary for achieving photobiological effects. Clinical observations suggested that such a threshold might apply to energy density, while further investigations seemed to indicate that a threshold for intensity (power density) might also be of importance. This was investigated in the clinical setting involving laser light applications to large areas. Initial measurements obtained with available measuring equipment pointed up the problems associated with the measurement of power and energy in different-speed radiation systems. Using a laser in conjunction with a "light chopper", a way of determining the range of a measuring system, in which useful measurements can be obtained is described.