The Fresnel Rhomb retarder offers unmatched performance in broad band, achromatic retardation.
These optics exploit the relative phase shift between orthogonal polarization states which occurs at the total internal reflection of a beam of light within a dielectric optic. Due to the large internal incidence angle required for this effect, these optics are very long and bulky.
The simplest design employs a single element. However, this means that the transmitted beam is strongly laterally displaced which can be very inconvenient – especially when the optic must be rotated. As an alternative, we offer dual elements which eliminate the lateral displacement. However, these items are even longer than the single elements.
As with all of our optics, we will gladly provide these items custom designed to your particular requirements. As an alternative, we offer a selection of standard items as specified below.
BK7 Fresnel Rhomb Retarder
Material: N-BK7
Flatness: λ/10 at 633nm
Surface Quality: 20-10 S/D (DIN: 5/2x0,1)
WavelengthRange: 400-2000 nm
Free Aperture: 10x10 mm
Order No. Retardation Design A (mm) B (mm) H (mm) 50.260.00086 lambda/4 single element 35.0 40.0 37.0 50.260.00087 lambda/2 dual element 64.0 40.0 37.0 50.260.00112 lambda/4 dual element 140.0 40.0 37.0
Fused Silica Fresnel Rhomb Retarder
Material: UV grade fused silica
Flatness: λ/10 at 633nm
Surface Quality: 20-10 S/D (DIN: 5/2x0,1)
WavelengthRange: 200-2000 nm
Free Aperture: 10x10 mm
Order No. Retardation Design A (mm) B (mm) H (mm) 50.260.00088 lambda/4 single element 35.0 40.0 37.0 50.260.00089 lambda/2 dual element 64.0 40.0 37.0 50.260.00113 lambda/4 dual element 140.0 40.0 37.0