Three dimensional information measurement method and apparatus

Abstract

A three dimensional information measurement apparatus employing a rotator or surface-of-rotation type mirror, an imaging apparatus disposed with its light receiving axis aligned with a center axis of said rotator type mirror for measuring three dimensional information on a target placed in a space surrounding said center axis, and a reference light projection means for projecting reference light. Also, main scanning is performing by deflecting the reference light in a circumferential direction centered about the center axis or, in an alternative embodiment, avoided by providing a conically shaped reference beam. Sub scanning is performed by deflecting said reference light in a direction of projection whereby said reference light changes in a direction parallel to said center axis either by changing the angle of the main scanning mirror; and three dimensional information computing means for obtaining the three dimensional information of said target, based on a physical quantity corresponding to a projection angle representing the direction of projection of said reference light in the sub scan, and on a physical quantity corresponding to the position of a projected image obtained by said imaging apparatus and representing said reference light reflected from said target via said rotator type mirror.