MIR Wire Grid Polarizers on Silicon Substrates

The engraving on the housing is parallel to polarized transmitted light and perpendicular to the orientation of the wires.

Features

• Polarize Light from 3 - 5 µm or 7 - 15 µm
• Extinction Ratio:
  • 3 - 5 µm (-IRA): >1000:1
  • 7 - 15 µm (-IRC): >10 000:1
• Offered 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
• Anodized Aluminum Mount with Transmission Axis Indicated

The mounted wire grid polarizers on silicon substrates sold here are designed to provide high extinction over two spectral ranges in the mid-IR: 3 - 5 µm (3333 - 2000 cm^-1) or 7 - 15 µm (1429 - 667 cm^-1). The 3 - 5 µm versions (denoted by -IRA) offer >1000:1 extinction and >85% average transmission over their specified range, while the 7 - 15 µm versions (denoted by -IRC) offer >10 000:1 extinction and >75% average transmission over their specified range. Wavelength-dependent plots of the transmission are available in the Specs tab. The polarizers are recessed inside Ø25.0 mm, 12.5 mm square, 25.0 mm square, or 50.0 mm square mounts fabricated from anodized aluminum. As shown by the drawings to the right, the mounts are engraved with the polarization axis of the transmitted light.

These MIR polarizers consist of a linearly spaced wire grid pattern that is deposited onto an AR-coated silicon substrate. Silicon was chosen because it offers good transmission in the mid-IR wavelength range. Because the wire grid absorbs and reflects radiation that is polarized parallel to the grid, the polarization of the transmitted radiation is perpendicular to the wires. These polarizers feature a mark on the housing to indicate the transmission axis (see diagrams to the right).

For smooth attenuation over the specified wavelength range and fine control over the output polarization direction, we recommend the Ø25.0 mm versions, which are well suited for use with our family of rotation mounts for Ø1" optics. The 12.5 mm square, 25.0 mm square, and 50.0 mm square versions can be secured in a cylindrical lens mount. Since our cylindrical lens mounts do not provide rotation, the square polarizers are best for applications that only require horizontal or vertical polarization.

The surface of a wire grid polarizer, like any diffraction grating, is extremely delicate. Never touch the surface of the polarizer, and only handle it by the edge. Careful removal of dust by gentle air flow is the only recommended cleaning procedure.

For broadband applications in the MIR, Thorlabs offers holographic wire grid polarizers for the 2 - 30 µm spectral range. In addition, we have wire grid polarizers on glass substrates for the 250 nm - 4 µm spectral range, which help enable the use of a visible alignment beam in a mid-IR experiment. For our complete selection of polarizers, please see the Polarizer Guide tab.

• The extinction ratio (ER) is the ratio of maximum to minimum transmission of a sufficiently linearly polarized input. When the transmission axis and input polarization are parallel, the transmission is at its maximum; rotate the polarizer by 90° for minimum transmission.
• Specified at normal incidence for light polarized parallel to the transmission axis of the polarizer.
• As shown by the drawing below, our square mid-IR polarizers have rounded corners that slightly reduce the clear aperture of the optic.
• With respect to the engraved line on the housing, as shown in the drawings below.

Engraving is Parallel to Transmitted Light Polarization

Polarizer Selection Guide

Thorlabs offers a diverse range of polarizers, including wire grid, film, calcite, alpha-BBO, rutile, and beamsplitting polarizers. Collectively, our line of wire grid polarizers offers coverage from the visible range to the beginning of the Far-IR range. Our nanoparticle linear film polarizers provide extinction ratios as high as 100 000:1. Alternatively, our other film polarizers offer an affordable solution for polarizing light from the visible to the Near-IR. Next, our beamsplitting polarizers allow for use of the reflected beam, as well as the more completely polarized transmitted beam. Finally, our alpha-BBO (UV), calcite (visible to Near-IR), rutile (Near-IR to Mid-IR), and yttrium orthovanadate (YVO₄) (Near-IR to Mid-IR) polarizers each offer an exceptional extinction ratio of 100 000:1 within their respective wavelength ranges.

To explore the available types, wavelength ranges, extinction ratios, transmission, and available sizes for each polarizer category, click More [+] in the appropriate row below.

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Wire Grid Polarizers on Glass Substrates	420 nm - 700 nm	>800:1 (Avg. Over Wavelength Range)		12.5 mm x 12.5 mm, Ø25.0 mmb, 25.0 mm x 25.0 mm, and 50.0 mm x 50.0 mm
	250 nm - 4 µm	>10:1 from 250 nm - 4 µm >100:1 from 300 nm - 4 µm >1000:1 from 600 nm - 4 µm >10 000:1 from 2.25 µm - 4 µm		12.5 mm x 12.5 mm, Ø25.0 mmb, 25.0 mm x 25.0 mm, and 50.0 mm x 50.0 mm
Wire Grid Polarizing Beamsplitter Cubes (Unmounted, 16 mm Cage Cube, or 30 mm Cage Cube)	400 nm - 700 nm	>1 000:1 (AOI: 0° - 5°) >100:1 (AOI: 0° - 25°)	P-Pol. S-Pol.	10 mm, 20 mme, and 1"e
Holographic Wire Grid Polarizers	2 µm - 12 µm	150:1 at 3 µm 300:1 at 10 µm		Ø25.0 mmb and Ø50.0 mmb
	2 µm - 9 µm	150:1 at 3 µm 300:1 at 8 µm
	2 µm - 30 µm	150:1 at 3 µm 300:1 at 15 µm
	2 µm - 18 µm	150:1 at 3 µm 300:1 at 10 µm
MIR Wire Grid Polarizers on Silicon Substrates	3 µm - 5 µm	>1000:1		12.5 mm x 12.5 mmb, Ø25.0 mmb, 25.0 mm x 25.0 mmb, and 50.0 mm x 50.0 mmb
	7 µm - 15 µm	>10,000:1		12.5 mm x 12.5 mmb, Ø25.0 mmb, 25.0 mm x 25.0 mmb, and 50.0 mm x 50.0 mmb

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Nanoparticle Linear Film Polarizers	365 nm - 395 nm	>1000:1 from 365 nm - 395 nm >10 000:1 from 369 nm - 390 nm >100 000:1 from 372 nm - 388 nm		Ø12.5 mmc and Ø25.0 mmd
	480 nm - 550 nm	>10 000:1 from 480 nm - 550 nm		Ø12.5 mmc and Ø25.0 mmd
	510 nm - 800 nm	>1000:1 from 510 nm - 800 nm >10 000:1 from 520 - 740 nm >100 000:1 from 530 - 640 nm		Ø12.5 mmc and Ø25.0 mmd
	550 nm - 1500 nm	>10 000:1 from 550 nm - 1500 nm >100 000:1 from 600 nm - 1200 nm		Ø12.5 mmc and Ø25.0 mmd
	650 nm - 2000 nm	>1000:1 from 650 nm - 2000 nm >10 000:1 from 750 nm - 1800 nm >100 000:1 from 850 nm - 1600 nm		Ø12.5 mmc and Ø25.0 mmd
	1 µm - 3 µm	>1000:1 from 1 µm - 3 µm >10,000:1 from 1.2 µm - 3 µm		Ø12.5 mmc and Ø25.0 mmd
	1.5 µm - 5 µm	>1000:1 from 1.5 µm - 5 µm >10 000:1 from 2 µm - 4.5 µm		Ø12.5 mmc and Ø25.0 mmd
Economy Film Polarizers	400 nm - 700 nm	>100:1 from 400 nm - 500 nm >1000:1 from 500 nm - 700 nm >5000:1 from 530 nm - 690 nm		2" x 2"
	600 nm - 1100 nm	>400:1 from 600 nm - 1100 nm >1000:1 from 600 nm - 940 nm		2" x 2"
Economy Laminated Film Polarizers	400 nm - 700 nm	>100:1 from 400 nm - 500 nm >1000:1 from 500 nm - 700 nm >5000:1 from 530 nm - 690 nm		Ø1/2", Ø1", and Ø2"
	600 nm - 1100 nm	>1000:1 from 600 nm - 950 nm >400:1 from 600 nm - 1100 nm		Ø1/2", Ø1", and Ø2"
	1050 nm - 1700 nm	>1000:1 from 1050 - 1400 nm >2000:1 from 1400 - 1700 nm		Ø1/2", Ø1", and Ø2"

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Polarizing Plate Beamsplitters	405 nm	>10 000:1		Ø1" and 25 mm x 36 mm
	532 nm
	633 nm
	780 nm
	808 nm
	1030 nm
	1064 nm
	1310 nm
	1550 nm
Polarizing Bandpass Filters	355 nm +6 nm / -9 nm	1 000 000:1		25.2 mm x 35.6 mm
	405 nm ± 5 nm
	532 nm +9 nm / -14 nm
Broadband Polarizing Beamsplitter Cubes (Unmounted, 16 mm Cage Cube, or 30 mm Cage Cube)	420 nm - 680 nm	1000:1		5 mm, 10 mm, 1/2", 20 mme, 1"e, and 2"
	620 nm - 1000 nm
	900 nm - 1300 nm
	1200 nm - 1600 nm
Wire Grid Polarizing Beamsplitter Cubes (Unmounted, 16 mm Cage Cube, or 30 mm Cage Cube)	400 nm - 700 nm	>1 000:1 (AOI: 0° - 5°) >100:1 (AOI: 0° - 25°)	P-Pol. S-Pol.	10 mm, 20 mme, and 1"e
Laser-Line Polarizing Beamsplitter Cubes (Unmounted or 30 mm Cage Cube)	532 nm	3000:1		10 mm, 1/2", 1"e
	633 nm
	780 nm
	980 nm			1"e
	1064 nm			10 mm, 1/2", 1"e
	1550 nm
High-Power Laser-Line Polarizing Beamsplitter Cubes (Unmounted or 30 mm Cage Cube)	355 nm	2000:1		1/2" and 1"e
	405 nm
	532 nm
	633 nm
	780 - 808 nm
	1064 nm
Calcite Beam Displacers	350 nmf - 2.3 µm (Uncoated)	-		10 mmb (Clear Aperture, Square)
Yttrium Orthovanadate (YVO4) Beam Displacers	488 nm - 3.4 µm (Uncoated)	-		>3 mm x 5 mm Ellipseg (Clear Aperture)
	2000 nm (V Coated)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
alpha-BBO Glan-Laser Polarizers	210 nm - 450 nm	100 000:1		5 mmb and 10 mmb (Clear Aperture, Square)
	220 nm - 370 nm
	405 nm
Wollaston Prism Polarizers	190 nm - 3500 nm			Ø10 mmb (Clear Aperture)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona,h	Available Sizes
Glan-Laser Calcite Polarizers	350 nmf - 2.3 µm (Uncoated)	100 000:1		5 mmb, 10 mmj, and 15 mmb (Clear Aperture, Square)
	350 nmf - 700 nm (A Coated)
	650 nm - 1050 nm (B Coated)
	1050 nm - 1700 nm (C Coated)
	1064 nm (V Coated)i
Glan-Taylor Calcite Polarizers	350 nmf - 2.3 µm (Uncoated)			5 mmb, 10 mmb, and 15 mmb (Clear Aperture, Square)
	350 nmf - 700 nm (A Coated)
	650 nm - 1050 nm (B Coated)
	1050 nm - 1700 nm (C Coated)
Glan-Thompson Calcite Polarizers (Unmounted or Mounted)	350 nmf - 2.3 µm (Uncoated)			5 mmj and 10 mmj (Clear Aperture, Square)
	350 nmf - 700 nm (A Coated)
	650 nm - 1050 nm (B Coated)
Double Glan-Taylor Calcite Polarizers	350 nmf - 2.3 µm (Uncoated)			9 mmb (Clear Aperture, Square)
Beam Displacers	350 nmf - 2.3 µm (Uncoated)			10 mmb (Clear Aperture, Square)
Wollaston Prism Polarizers	350 nmf - 2.3 µm (Uncoated)			Ø10 mmj (Clear Aperture)
	350 nmf - 700 nm (A Coated)
	650 nm - 1050 nm (B Coated)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Wollaston Prism Polarizers	400 nm - 2000 nm	10 000:1		Ø10 mmb (Clear Aperture)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Wollaston Prism Polarizers	200 nm - 6.0 µm	10 000:1		Ø10 mmb (Clear Aperture)
Rochon Prism Polarizers				10 mm x 10 mm (Clear Aperture)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Beam Displacers	488 nm - 3.4 µm (Uncoated) 2000 nm (V Coated)	100 000:1		>3 mm x 5 mm (Clear Aperture, Ellipse)
Wollaston Prism Polarizers	900 nm - 3.24 µm			Ø10 mmb (Clear Aperture)
Rochon Prism Polarizers	488 nm - 3.4 µm			10 mm x 10 mmb (Clear Aperture)

Polarizer Type	Wavelength Range	Extinction Ratio	Transmissiona	Available Sizes
Rutile TiO2 Polarizers	2.2 µm - 4 µm	100 000:1		9.1 mm x 9.5 mm x 9.5 mmb and 10.7 mm x 15.9 mm x 15.9 mmb

• Click on the graph icons in this column to view a transmission curve for the corresponding polarizer. Each curve represents one substrate sample or coating run and is not guaranteed.
• Mounted in a protective box, unthreaded ring, or cylinder.
• Available unmounted or in an SM05-threaded (0.535"-40) mount that indicates the polarization axis.
• Available unmounted or in an SM1-threaded (1.035"-40) mount that indicates the polarization axis.
• Available unmounted or mounted in cubes for cage system compatibility.
• Calcite's transmittance of light near 350 nm is typically around 75% (see Transmission column).
• Available unmounted or in an unthreaded Ø1/2" housing.
• The transmission curves for calcite are valid for linearly polarized light with a polarization axis aligned with the mark on the polarizer's housing.
• The 1064 nm V coating corresponds to a -C26 suffix in the item number.
• Available unmounted or mounted in a protective box or unthreaded cylinder that indicates the polarization axis.