摘要 |
A grating device with a substantially polarization-independent diffraction efficiency is disclosed. The grating device is preferably a surface grating that can be produced by ruling or holographically, and includes at least two different grating elements with the same grating period, but different modulation depths or blaze angles. The blaze angles and the illuminated areas of the respective grating elements can be selected to produce a substantially polarization-independent and optionally also wavelength-independent response of the grating device. |