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Wire grid polarizers are commonly used to polarize radiation from an unpolarized laser, attenuate radiation from a polarized laser and are also used in accessories for dispersive and FT-IR spectrophotometers. Optometrics produces both ruled and holographic polarizers on a wide variety of infrared materials such as ZnSe, CaF2, BaF2, KRS-5 and Germanium. We provide a wide variety of options depending on the wavelength range of interest and your damage threshold requirements. Read on for more information!
All the best in Wavelength Selection Solutions,
Laura Lunardo
Chief Operating Officer
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| Ruled Wire Grid Polarizers |
 With three ruling engines in a controlled environment, Optometrics can rule polarizers with groove spacings of up to 1200 grooves per mm. We manufacture ruled polarizers by ruling precisely spaced grooves directly into high polished CaF2 or ZnSe substrates. The ruling process forms sharp, well defined peaks which are then coated with aluminum at an oblique angle, resulting in a series of closely spaced, highly conductive wires with a high extinction ratio and an inherently high damage threshold, allowing the use of the ruled polarizers with relatively high power lasers. Typical damage thresholds are 100 W/cm2 CW and 2 J/cm2 pulsed. Back to the top |
| Holographic Wire Grid Polarizers |
 Two well equipped holographic laboratories support both routine production and new product development. Capabilities permit groove spacings of 100 - 2700 grooves per mm. To produce a holographic polarizer, an interferometrically generated pattern is produced from monochromatic light and exposed onto a photo-resist coated sustrate. Once developed, the resist has a regular sinusoidal profile which is vacuum aluminized at an oblique angle to create the array of parallel conductors. The fabrication of holographic wire grid polarizers permits the use of a wide variety of infrared materials that do not lend themselves to the ruling process such as BaF2, KRS-5 and Germanium, in addition to the traditional ZnSe and CaF2. They are available with a spacing of 2700 grooves/mm for optimum short wavelength efficiency.
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| Overcoatings |
 Calcium Fluoride (CaF2) and Barium Fluoride (BaF2) have low refractive index (high Tx) values and do not require anti-reflective (AR) coatings. Zinc Selenide (ZnSe) has a high refractive index and transmission at specific wavelength regions which can be enhanced by an AR coating on the rear surface only. ZnSe is usually optimized for transmission at specific laser lines, typically from 9 to 11 microns. KRS-5 is not normally AR coated because this would limit its broad transmission range which is its primary advantage. Germanium (Ge) is AR/AR coated to maximize transmission at 10.6 microns.
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