Patent ID: 8264696

Claim:
A measuring instrument for determining at least one geometric property of a profile section, comprising an assembly which produces at least one first collimated light beam and one second collimated light beam, wherein a beam direction of the first collimated light beam is different from a beam direction of the second collimated light beam, a retro-reflecting surface, which is arranged with respect to a light source of the assembly so that at least the first collimated light beam is incident at least partially on the retro-reflecting surface, and a recording device which determines a light intensity distribution in a transverse dimension of at least a portion of a first reflected light beam produced when the first collimated light beam is reflected by the retro-reflecting surface, said recording device also determining a light intensity distribution in the transverse dimension of at least a portion of the second light beam or of at least a portion of a second reflected light beam produced when the second collimated light beam is reflected by the retro-reflecting surface or by another retro-reflecting surface.