Patent ID: 7312862

Claim:
A measurement system for determining six degrees of freedom (α, β, d, φ, χ, ψ) of a reflector ( 2 ) or of an object ( 3 ) on which the reflector ( 2 ) is arranged, said measurement system comprising: an angle and distance measurement apparatus ( 1 ) emitting a laser beam as a measurement beam ( 4 ), the reflector ( 2 ) being designed for a parallel reflection of the measurement beam ( 4 ) and comprising an apical opening or surface ( 6 ); a light-sensitive surface ( 7 ) arranged behind the reflector apex in a manner such that a part of the measurement beam ( 4 ) directed onto the reflector ( 2 ) passes through the apical opening or surface ( 6 ) of the reflector ( 2 ) and is incident on the surface ( 6 ), which is light sensitive; an optically detectable addition element ( 10 ) which is stationary relative to the reflector ( 2 ) and is detected from the angle and distance measurement apparatus ( 1 ), or is stationary relative to the angle and distance measurement apparatus ( 1 ) and is detected from the object ( 3 ), the optically detectable addition element ( 10 ) defining a direction ( 21 ) or a line which does not lie on a reflector axis (A) nor on the measurement beam ( 4 ); and a computer ( 8 ) being equipped for computing five degrees of freedom (α, β, d, φ, χ) of the reflector ( 2 ) or the object ( 3 ), from the measurement data produced by the angle and distance measurement apparatus ( 1 ) and by the light-sensitive surface ( 7 ) and for computing the sixth degree of freedom (ψ) of the reflector ( 2 ) or the object ( 3 ) from measurement data obtained by the detection of the addition element ( 10 ).