Polarisation element having high optical quality

摘要

Polarisation element (I) has a Faraday medium made of a Tb-Sc-Al garnet in the form of Tb3SixAl2-xO12 (where x = 0-1.905) having a Verdet constant of 156 rad.T<-1>.m<-1> and 49.2 rad.T<-1>.m<-1> at wavelengths of 633 nm and 1060 nm respectively, and an optical absorption of less than 1% over the wavelength region. Prodn. of (I) is also claimed.