Patent ID: 7252411

Claim:
Device for depicting a linear optical marking in a room, comprising a housing with a light source emitting the light along an optical axis and a lens having a trough shaped geometry that both reflects the light and allows it to pass, the lens being arranged in front of the light source and through which the optical axis extends, the lens having a longitudinal axis transverse to the optical axis of the light source, the lens having a first section extending on the light source side with an outer surface upon which light emitted by the light source impinges and is linearly focused via an optical unit, the outer surface of the first section reflecting light in a direction of the light source all the way into an area that extends beneath, to the side of or above the light source as a function of the course of the longitudinal axis to the lens and into the area of the room that faces away from the light source in terms of the light source, the light passing through first section impinging on a second section of the lens facing away from the light source and which is refractive for generating a linear optical marking in an area of the room distal to the light source.