Apparatus for photographing road ruts

Claim 1

Apparatus for photographing a road surface to evaluate the presence of ruts therein, said apparatus comprising a vehicle adapted for traveling along a road whose surface is to be evaluated for ruts, light projecting means on said vehicle for projecting a beam of light on the road surface to form a linear boundary between an illuminated and a non-illuminated portion of the road extending transversely thereof, said light projecting means being oriented on said vehicle to direct said beam of light onto said road at an acute angle thereto and camera means on said vehicle for photographing said boundary, said camera means being mounted on said vehicle such that the axis of the camera is perpendicular to the road surface and is at a predetermined angular position in relation to said light projecting means, said light projecting means comprising a light source including a flash lamp, a condensor lens in front of said flash lamp, a projection lens in front of said condensor lens and a shading plate interposed between said condensor lens and said projection lens, said shading plate including one portion opaque to the light source and another portion pervious to the light source.