Patent ID: 7954248

Claim:
An arrangement for depicting a linear optical marking on a surface, such as a peripheral surface such as a wall surface of a room, comprising a radiation source ( 20 ) emitting a light or laser beam, as well as a first lens ( 18 , 20 , 36 , 57 ) arranged in the beam path having a first and a second surface ( 38 , 40 , 44 , 46 , 56 , 58 ) penetrated by the beam, of which one surface features a parabolic or elliptical trace at least partially in cross section, comprised of curved sections of different radii, said trace extending symmetrically with respect to a plane of symmetry ( 42 ) of the lens, along which runs the beam directed in parallel, preferably by means of a second lens ( 22 ), wherein the first surface ( 38 ) comprising sections with different radii faces the beam.