A laser system for body tissue treatment has laser source, control device, scanner, and handpiece with treatment head transparent to the laser beam. An incoming laser beam section enters the treatment head longitudinally. The treatment head has a conical output surface with a minimum and a maximum surface radius and a half opening angle for total reflection of the incoming beam section. The reflected beam section is refracted radially into an emerging beam section away from the treatment head through the output surface. The incoming beam section has at the output surface a mean diameter that is ≦a difference of maximum surface radius and minimum scanning radius. A conical scanning surface as a part of the conical output surface extends from the minimum scanning radius to the maximum surface radius. The control device controls the scanner for scanning the conical scanning surface with the incoming beam section.
