Patent ID: 9667019
Date: 2017-05-30
CPC Classifications: H01S,H05G

Claim:
1. A laser apparatus comprising: a master oscillator configured to output pulsed laser light; two or more power amplifiers disposed in an optical path of the pulsed laser light to amplify the pulsed laser light; and a plurality of optical isolators, each provided between adjacent two of the power amplifiers in the optical path of the pulsed laser light, and each configured to suppress transmission of light traveling from the power amplifiers to a side where the master oscillator is provided, at least one of the optical isolators including a first retarder, wavelength filter configured to allow light with a wavelength of the pulsed laser light to pass therethrough, and suppress transmission of light with a wavelength other than the wavelength of the pulsed laser light, a first polarizer configured to provide a phase difference of ¼ wavelength, an EO Pockels cell, a second retarder, a third retarder configured to provide a phase difference of ½ wavelength, and a second polarizer, and the wavelength filter including a substrate and a multilayer film, the substrate containing ZnSe, and the multilayer film being provided on a surface of the substrate and containing ZnSe and ThF