Application of metallic subwavelength gratings for polarization devices

E-beam lithography offers the possibility for fabricating metallic subwavelength gratings for visible light which show strong polarization properties. By using such gratings and other micro-optical elements (like lenses and diffraction gratings) a new kind of polarization detector without mechanical motion is proposed. The basic idea is the use of a special analyzing grating element with different grating directions (e.g. a circular metallic subwavelength grating). We realized both a wavelength-independent polarimeter and a polarimeter with spectroscopic properties. Characteristic parameters estimated are the angular resolution of the polarization plane (best value 0.001 degree) and the wavelength resolution (best value 15 nm).