Optical Polarisers
Sheet polarisers-Visible range
The former ‘Polaroid’ materials are now made by 3M under the name ‘Vikuiti’. In addition to the standard grades we offer the newer types HN38S and HN42HE, which combine very good extinction with high transmittance, at some extra cost, and HN22 which has the widest wavelengths outside this range.
As a result of the 3M takeover, some materials are likely to become obsolete, although we large stocks are available at present.
Circular polarisers
Polaroid circular polariser HNCP37 consists of a linear polariser laminated to a quarter-wave plate. It’s commonest use is to block specular reflections from displays. The matt non-glare finish helps to suppress reflections from the polariser it self, but can only be used where the polariser is very close to the display.
Crystal polarisers
The basic Glan-Taylor polarising prism gives excellent extinction and high transmittance over a wide wavelength range. The form with side faces polished is useful as a polarising beamsplitter or for high powers.
The high-transmittance type, also with side windows, has all four surfaces at Brewster’s angle for the transmitted beam, so reflection losses are negligible.
The Wollaston polarising beamsplitter, a cemented type, deviates the two polarisation components of a beam at angles ±10 degrees from input direction, with a small chromatic dispersion.
Most types are also listed mounted in flanged clevis mounts, these fit directly, for instance, into our rotating holders and Tube Mount system, whilst still allowing access to the side exit beam.
Cube polarisers
Polarising beamsplitter cubes conveniently divide any beam into two polarised components. They also make excellent variable beamsplitters, particularly for sources such as lasers with polarised output, used with a half-wave plate to vary the incident polarisation state. This arrangement allows continuous variation of the split ration over a wide range with negligible losses.
We offer cubes for both with multiplayer AR coatings for maximum efficiency. Note that the polarisation purity of the transmitted beam is considerably better than the reflected beam. For even better performance see crystal polarisers.
Cubes are also listed mounted in a flanged clevis mount to fit directly into our rotating holders, Tube Mount cells and similar mounts, whilst still allowing access to the reflected beam.
Sheet polarisers-UV and IR range
The HNP’B polariser, a modified polyvinyl alcohol iodine type, covers the UV down to 280nm and is also an excellent polariser for the visible region.
The HR polariser covers the whole range from 800nm to 2.0 microns. However for wavelengths between 800nm and 860nm the HN7 type is preferable as having higher transmittance and being considerably less expensive. Below 800nm use the standard type HN22.
3M, except HN7 which is obsolescent, now make these materials from the former Polaroid range.
Other Polarizer PDFs
PDF for HN385
PDF for HN42
PDF for HN42E