Glan-Thompson Polarizing Prisms

The prisms are produced from calcite of selected quality which is practically striae- and bubble-free. The usable spectral range is 300 - 2700 nm. The extinction ratio is better than 10^-6 and flatness of the outer surfaces is better than λ/4 (λ = 550 nm). The deformation of a transmitted plane wave is less than λ/4. Prismatic deviation is less than about 2'. The side faces are lacquered in matt black to absorb the totally reflected ordinary beam. Only a small amount of stray light emerges from the side faces mainly caused by the reflected („rejected") light from the inner surface. A possibly disturbing influence of this stray light can be avoided by a sufficient distance between polarizer and analyzer or between analyzer and receiver.
In the visible spectral range the maximum laser power is about 200 W/cm² cw for the transmitted beam and up to 30 W/cm² cw (3 W cw) for the ray absorbed on the prism side.
The Glan-Thompson prisms are available in a long and a short version. For the long version the ratio of cross section to length is 1:3. The angle between the entrance and inner faces is 73° and provides a polarized, symmetrical field of view of ±15° at 550 nm. The short version has a ratio of cross section to length equal to 1:2. The cutting angle is 67°30' and provides a polarized, symmetrical field of view of ±6° at 550 nm.

Long version - mounted

Long version - unmounted

Short version - mounted

Short version - unmounted

Short version in simple quality

These prisms are made of standard grade calcite which may contain slight striae. The extinction ratio is better than 10^-5. Flatness of the outer surfaces is better than 1 λ . Deformation of a transmitted plane wave is less than 2 λ. The prismatic deviation is less than about 5'.
High power levels should be avoided, especially below 400 nm.
These prisms usually can not be supplied in interferometer quality.
This quality can also be supplied in a smaller size (5.5 mm). The other specifications are the same as the ones given for the standard quality prisms described above.

Glan-Thompson prisms in UV quality

These prisms are made of specially selected UV-grade calcite. The prisms are joined with UV transmitting cement. The usable spectral range is 250 - 2700 nm. The ratio of cross section to length is about 1:1.8. The prisms are made with an angle between the entrance and inner faces of 64°. The polarized, symmetrical field of view of ±9° at 550 nm.
The other specifications are the same as the ones given for the standard quality prisms described above. For high powers in the UV we recommend to use Glan prisms with air gap.

Please note

For angular orientation these prisms can be mounted in the Rotating Mounts.

Available on special order

• Interferometer quality:
  Deformation of a transmitted plane wave less than λ/10, Flatness of outer surfaces λ/10, Deviation less than 5" → PGT 0.1
• Extinction ratio better than 10^-7 → PGT 0.7
• Extinction ratio better than 10^-8 → PGT 0.8
• Antireflection coating (The prisms in interferometer quality can only be supplied without antireflection coating) → on request