title: Polarization-independent light-dispersing optical device consisting of two diffraction gratings and a waveplate.
abstract: We report on a light-dispersing device consisting of two transmission gratings and a waveplate. The gratings separate two orthogonal polarization components of light incident at the Bragg angle. The waveplate, which is sandwiched between the gratings, functions as a polarization converter for oblique light incidence. With these optical parts suitably integrated, the resulting device efficiently diffracts unpolarized light with high spectral resolution. Using coupled-wave theories and Mueller matrix analysis, we constructed a device for a wavelength range of 680±50  nm with a 400 nm grating period. From the characterization of this optical device, we validated the proposed polarization-independent, light-dispersing concept.
authors.forename: J
authors.initials: J
authors.lastname: Amako
authors.forename: E
authors.initials: E
authors.lastname: Fujii