The extinction ratio of the installed silicon based linear grating polarizers sold here is very high in these two mid infrared spectral ranges: 3-5 µm (3333-2000 cm-1) or 7-15 µm (1429-667 cm-1). The extinction ratio of 3-5 µm (called – IRA) is greater than 1000:1, and the average transmittance is greater than 85% in the specific wavelength range, while the extinction ratio of 7-15 µm (called – IRC) is greater than 10000:1, and the average transmittance is greater than 75% in the specific wavelength range. There is a wavelength transmittance diagram in the specification label. The polarizers are mounted at 25.0 mm, 12.5 mm and 25.0 mm square or 50 mm square anodized aluminum mount.

These mid infrared polarizers have a linear grid pattern deposited on the antireflective silicon substrate. Silicon was chosen as the substrate because of its high transmittance in the mid infrared wavelength range. Because the line grid absorbs and reflects the polarized light of the parallel grid, the polarization direction of the transmitted light is perpendicular to the line.

If the attenuation is required to be smooth in a specific wavelength range and the polarization direction of the output light is controlled slightly, we recommend the Ø 25.0 mm version, which is just suitable for use with our Ø 1-inch optical rotary mount. The 12.5 mm square, 25.0 mm square and 50.0 mm square versions can be fixed in the lenticular mount. Because our cylindrical lens mount cannot rotate, directional polarizers are best used where only horizontal or vertical polarization is required.

Like any diffraction grating, the surface of linear grating polarizer is very fragile. Never touch the surface of the polarizer, only the edge. Only gentle airflow is recommended.


Basic Parameters

Wavelength range3-5 µm
(3333 – 2000
7-15 µm
(1429 – 667
Product IDPA03002aPA03002b


  • The wavelength range of polarized light is 3-5 µm or 7-15 µm
  • High extinction ratio
  • Available in four sizes Ø25.0 mm 12.5 mm x 12.5 mm 25.0 mm x 25.0 mm 50.0 mm x 50.0 mm
  • Provide anodized aluminum mount marked with transmission shaft
Extinction ratio>1000:1 Over the entire wavelength range
Accuracy of transmission shaft±2°
Wire spacing144 nm
Steel wire thickness65 nm
thermal expansion2.6 x 10-6 per °C
Thermal expansion substrateAR-Coated Silicon


MIR Wire Grid Polarizers on Silicon Substrates Spectrogram1
MIR Wire Grid Polarizers on Silicon Substrates Spectrogram2
MIR Wire Grid Polarizers on Silicon Substrates Spectrogram3
MIR Wire Grid Polarizers on Silicon Substrates Spectrogram4