| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical delay device whose delay amount is larger when the size of the optical delay device is the same as that of a conventional optical delay device, and whose size is smaller when the delay amount is the same as that of a conventional device.SOLUTION: The optical delay device includes: a first retroreflector which reflects light made incident from one of a first optical path and a second optical path which are parallel to each other on a first plane to the other, and reflects the light made incident from one of a third optical path and a fourth optical path which are parallel to the first and second optical paths on a second plane parallel to the first plane to the other; a second retroreflector which faces the first retroreflector and reflects the light made incident from one of the second and third optical paths to the other; an incident optical system which makes the light incident on the first optical path in a direction incident to the first retroreflector; a light-receiving optical system which receives the light made incident from the incident optical system and delayed on a delay optical path including the first to fourth optical paths and the first and second retroreflectors; and distance adjustment means which adjusts a distance between the first and second retroreflectors.SELECTED DRAWING: Figure 1 |
