| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical attenuator whose constitution is simple and which is manufactured without using an expensive member. SOLUTION: The attenuator consisting of an optical part in which a first 1/2 wavelength plate, a variable Faraday rotator and a second 1/2 wavelength plate are arranged in order and a coupled optical system by which parallel luminous flux is transmitted to the optical part is disposed so that either of the luminous flux obtained by dividing the cross section of the parallel luminous flux into equal halves is transmitted through the first 1/2 wavelength plate and the variable Faraday rotator and the other of the luminous flux obtained by dividing the cross section of the parallel luminous flux into the equal halves is transmitted through the variable Faraday rotator and the second 1/2 wavelength plate.
|
