An optical compensator is described which is achromatized in a broad spectral range. It consists of two pairs of birefringent plates of different materials under oblique incidence rotated around the normal to the plates. The phase shift is achromatized by adjusting the plate thicknesses. An electrooptic modulator based on this design is also described. Instead of mechanically rotating the system to introduce phase shifts the optic axis is rotated by applying an electric field.
© 1989 Optical Society of America
1. Filinski and Torben Skettrup, "Achromatic optical compensator-modulator," Appl. Opt. 28, 1720-1726 (1989)