Patent ID: 6888652

Claim:
A method of testing an optical collimator having an optical axis using a mirror for reflecting light emitted from the optical collimator, the method comprising the steps of: moving either one of the mirror and the optical collimator; and measuring the intensity of light reflected by the mirror to the optical collimator and passing through the optical collimator while moving said either one of the mirror and the optical collimator, wherein the step of moving said either one of the mirror and the optical collimator includes: reciprocally rotating said either one of the mirror and the optical collimator about a first axis substantially orthogonal to the optical axis at a first speed; and reciprocally rotating said either one of the mirror and the optical collimator about a second axis substantially orthogonal to the optical axis and the first axis at a second speed different from the first speed simultaneously with the rotating about the first axis.