Our Glan-Thompson Calcite Polarizers provide high purity linear polarization for broadband sources or multiple laser wavelengths for lower power applications. Their 14°-16° acceptance angle allows them to be used in highly converging or diverging beams. The housing mounts into our standard 25.4 mm holders, and the polarizers are offered with broadband AR coatings for the visible and NIR regions.
Wide acceptance angle with superior broadband performance
Extinction ratio >100,000:1
Low wavefront distortion
Best select-grade calcite
S-polarization is transmitted with Ts >90%
P-polarization is rejected and absorbed within the housing
Glan-Thompson Polarizer Construction
Our Glan-Thompson polarizers are fabricated using two matching select-grade calcite prisms with their hypotenuses cemented to one another to form a rectangular optic. The cemented prism pair is assembled into a black anodized aluminum housing. The housing is marked to indicate the polarization axis of the transmitted beam. The rejected component of the beam is totally internally reflected and eventually absorbed by the anodized aluminum walls of the housing.
How Glan-Thompson Calcite Polarizers Work
Glan-Thompson prisms are formed using two identical calcite prisms with hypotenuses cemented to one another to form a surface that efficiently transmits one polarization state specifically. The prisms have the same optic axis orientation as one another, which is perpendicular to the plane of reflection (the shared hypotenuse). Light that is s-polarized with respect to the reflective hypotenuse experiences the higher ordinary refractive index of calcite. Because calcite has a large index difference between extraordinary and ordinary rays, the polarizer has a fairly wide range of acceptance angles that result in transmission of only highly pure p-polarized light. Thus Glan Thompson prisms have a wide usable acceptance angle and are especially well suited for use with diverging and converging beams.
Mounting the Aluminum Housing
The Glan-Thompson polarizer has a black anodized aluminum housing. The knurl ring found at the center of the housing will unscrew to yield a 1.063-20 thread. This thread conveniently screws into popular rotation stages such as the 481-A, RS65 or RSP-1T.