METHOD FOR REDUCING COHERENCE OF LIGHT AND DEVICE THEREFOR, METHOD FOR ILLUMINATION AND DEVICE THEREFOR AND BUNDLE FIBER

摘要

PROBLEM TO BE SOLVED: To reduce the coherence of a light in a simple constitution. SOLUTION: A coherent lightαis made incident to an incident end part 3 of a bundle fiber 1 constituted of plural optical fibers 2a, 2b,... with different length which is the coherence length of the coherent lightαor more, and emitted as a coherent optical beam from a light outgoing side fiber bundle part 4 of the bundle fiber 1.