An apparatus for treating an inner surface of a workpiece

The invention relates to a device (1, 20, 40, 60, 80, 90) for treating an inner surface (O) of a workpiece (W), with a radiation (P, P ', I), with at least one production unit (2 , 20, 41, 62) for generating the radiation (P, P ', I), with a drive unit (45, 86, 94) for rotating said at least (a generating unit 2, 20, 41, 62) about a rotational axis (13 , 34, 47, 63, 87, 93), wherein the at least one production unit (2, 20, 41, 62) for delivering the generated radiation (P, P ', I) (with a preferred direction V, V', V " , V '') ', V' '' 'is formed in the direction of the surface to be treated (O). Thus, an inner surface of a material can be processed with short contact times of the radiation, it is provided that a (with the at least one generating unit 2, 20, 41, 62) arm connected (10, 22, 42, 61, 85, 95) for introducing the forming unit (2, 20, 41, 62) in the workpiece (W) is provided and that the rotational axis (13 , 34, 47, 63, 87, 93 ) And the preferred direction (V, V ', V', V '' ', V' '' ') are inclined to each other.