| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the adjustment of the optical axis of outgoing light and to be able to continuously change the light quantity. SOLUTION: In the device 10, same polarizing beam splitters 14 and 15 different in transmission quantity corresponding to polarization component are symmetrically arranged against a plane orthogonal to the rotary axis of an inner lens barrel 12 arranged in an outer lens barrel 11 so that it can freely rotate by inclining them at an angleθby using a holding member 13. When an optical axis makes the linear polarizing light from a laser light source 1 enter so that it may be matched with the rotary axis of the inner lens barrel 12 and the inner lens barrel 12 is rotated to a desired position, the rate of the polarization components of laser light beams which are made incident on the polarizing beam splitters 14 and 15 changes in accordance with a rotary angle. Thus, the light quantity of outgoing light continuously changes and the optical axis shift and the angle blurring of the beam splitters 14 and 15 are canceled by each other. Consequently, an outgoing optical axis is always matched with an incident optical axis. |
