Rochon Prisms

Overview
BS Selection Guide
Prism Guide
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Polarizer Guide

Specifications
Item #	RPM10	RPV10
Substrate^a	MgF₂	YVO₄
Substrate Wavelength Range	200 nm - 6.0 µm	488 nm - 3.4 µm
Transmission (Click for Graph)	Raw Data	Raw Data
Beam Separation Angle (Typical)	1.5° at 4 µm	10.6° at 2 µm
Beam Deviation (Click for Graph)	Raw Data	Raw Data
Extinction Ratio^b	>10 000:1	>100 000:1
Clear Aperture (Min)	10 mm x 10 mm
Transmitted Wavefront Error	λ/4 at 633 nm
Surface Quality	20-10 Scratch-Dig
Optic Thickness	35 mm	12 mm
Housing Dimensions	Ø1.00" x 1.55" (Ø25.4 mm x 39.4 mm)	Ø1.00" x 0.55" (Ø25.4 mm x 14.0 mm)

Click the links for detailed specifications on the substrates.
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.

Click to Enlarge
The housing is engraved with a diagram showing the input and output beams.

Features

Separate Unpolarized Light into Two Orthogonally Polarized Outputs
1.5° or 10.6° Beam Separation Angle
High Extinction Ratio for Each Output
Uncoated Magnesium Fluoride or Yttrium Orthovanadate Substrate
Mounted in Ø1" Aluminum Housing

Thorlabs' Rochon Prisms split an arbitrarily polarized input beam into two orthogonally polarized output beams. The ordinary ray remains on the same optical axis as the input beam, while the extraordinary ray deviates by an angle, which depends on the wavelength of the light and the material of the prism (see the Beam Deviation graphs in the table to the right). The output beams have a high polarization extinction ratio of >10 000:1 for the MgF₂ prism and >100 000:1 for the YVO₄ prism. See the table to the right for complete specifications.

Each prism is mounted in a Ø1" anodized aluminum housing. The housing is engraved with the item # and a diagram showing the direction and polarization states of the input and output beams. The prism housing can be mounted in an SM1 lens tube using a retaining ring. The lens tube can then be threaded onto a rotation mount or other SM1-threaded mount for use in a variety of applications.

If your application would benefit from an unmounted Rochon prism or a prism with an AR coating, please contact Tech Support.

Birefringent Crystal Beamsplitters
Type	Ordinary Ray Angle^a	Extraordinary Ray Angle^a
Calcite Beam Displacers	Parallel	Parallel
YVO₄ Beam Displacers	Parallel	Parallel
Rochon Prisms	Parallel	Deviated
Wollaston Prisms	Deviated	Deviated

With Respect to Input Beam

Schematic and Ray Diagram of Mounted Rochon Prisms

Thorlabs' portfolio contains many different kinds of beamsplitters, which can split beams by intensity or by polarization. We offer plate and cube beamsplitters, though other form factors exist, including pellicle and birefringent crystal. Many of our beamsplitters come in premounted or unmounted variants. Below is a complete listing of our beamsplitter offerings. To explore the available types, wavelength ranges, splitting/extinction ratios, transmission, and available sizes for each beamsplitter category, click More [+] in the appropriate row below.

Non-Polarizing Beamsplitters

Plate Beamsplitters

Cube Beamsplitters

Pellicle Beamsplitters

45° AOI Unless Otherwise Noted

Polarizing Beamsplitters

Plate Beamsplitters

Cube Beamsplitters

Birefringent Crystal Beamsplitters

PBS519: Average T_P:T_S > 1000:1
Mounted in a protective box, unthreaded ring, or cylinder.
Available unmounted or mounted in a protective box or unthreaded cylinder.

Other Beamsplitters

Other Beamsplitters

Selection Guide for Prisms

Thorlabs offers a wide variety of prisms, which can be used to reflect, invert, rotate, disperse, steer, and collimate light. For prisms and substrates not listed below, please contact Tech Support.

Beam Steering Prisms

Prism	Material	Deviation	Invert	Reverse or Rotate	Applications
Right Angle Prisms	N-BK7, UV Fused Silica, Calcium Fluoride, or Zinc Selenide	90°	90°	No	90° reflector used in optical systems such as telescopes and periscopes.
Right Angle Prisms	N-BK7, UV Fused Silica, Calcium Fluoride, or Zinc Selenide	180°	180°	No	180° reflector, independent of entrance beam angle. Acts as a non-reversing mirror and can be used in binocular configurations.
TIR Retroreflectors (Unmounted and Mounted) and Specular Retroreflectors (Unmounted and Mounted)	N-BK7	180°	180°	No	180° reflector, independent of entrance beam angle. Beam alignment and beam delivery. Substitute for mirror in applications where orientation is difficult to control.
Unmounted Penta Prisms and Mounted Penta Prisms	N-BK7	90°	No	No	90° reflector, without inversion or reversal of the beam profile. Can be used for alignment and optical tooling.
Roof Prisms	N-BK7	90°	90°	180^o Rotation	90° reflector, inverted and rotated (deflected left to right and top to bottom). Can be used for alignment and optical tooling.
Unmounted Dove Prisms and Mounted Dove Prisms	N-BK7	No	180°	2x Prism Rotation	Dove prisms may invert, reverse, or rotate an image based on which face the light is incident on. Prism in a beam rotator orientation.
Unmounted Dove Prisms and Mounted Dove Prisms	N-BK7	180°	180°	No	Prism acts as a non-reversing mirror. Same properties as a retroreflector or right angle (180° orientation) prism in an optical setup.
Wedge Prisms	N-BK7	Models Available from 2° to 10°	No	No	Beam steering applications. By rotating one wedged prism, light can be steered to trace the circle defined by 2 times the specified deviation angle.
Wedge Prisms	N-BK7	Models Available from 2° to 10°	No	No	Variable beam steering applications. When both wedges are rotated, the beam can be moved anywhere within the circle defined by 4 times the specified deviation angle.
Coupling Prisms	Rutile (TiO₂) or GGG	Variable^a	No	No	High index of refraction substrate used to couple light into films. Rutile used for n_film > 1.8 GGG used for n_film < 1.8

Depends on Angle of Incidence and Index of Refraction

Dispersive Prisms

Prism

Material

Deviation

Invert

Reverse or Rotate

Illustration

Applications

Equilateral Prisms

F2, N-SF11, Calcium Fluoride,
or Zinc Selenide

Variable^a

Dispersion prisms are a substitute for diffraction gratings.

Use to separate white light into visible spectrum.

Dispersion Compensating Prism Pairs

Fused Silica, Calcium Fluoride, SF10, or N-SF14

Variable Vertical Offset

Compensate for pulse broadening effects in ultrafast laser systems.

Can be used as an optical filter, for wavelength tuning, or dispersion compensation.

Pellin Broca Prisms

N-BK7,
UV Fused Silica,
or Calcium Fluoride

90°

Ideal for wavelength separation of a beam of light, output at 90°.

Used to separate harmonics of a laser or compensate for group velocity dispersion.

Depends on Angle of Incidence and Index of Refraction

Beam Manipulating Prisms

Prism

Material

Deviation

Invert

Reverse or Rotate

Illustration

Applications

Anamorphic Prism Pairs

N-KZFS8 or
N-SF11

Variable Vertical Offset

Variable magnification along one axis.

Collimating elliptical beams (e.g., laser diodes)

Converts an elliptical beam into a circular beam by magnifying or contracting the input beam in one axis.

Axicons

UV Fused Silica
or Zinc Selenide

Variable^a

Creates a conical, non-diverging beam with a Bessel intensity profile from a collimated source.

Depends on Prism Physical Angle

Polarization Altering Prisms

Prism	Material	Deviation	Invert	Reverse or Rotate	Applications
Glan-Taylor, Glan-Laser, and α-BBO Glan-Laser Polarizers	Glan-Taylor: Calcite Glan-Laser: α-BBO or Calcite	p-pol. - 0° s-pol. - 112°^a	No	No	Double prism configuration and birefringent calcite produce extremely pure linearly polarized light. Total Internal Reflection of s-pol. at the gap between the prism while p-pol. is transmitted.
Rutile Polarizers	Rutile (TiO₂)	s-pol. - 0° p-pol. absorbed by housing	No	No	Double prism configuration and birefringent rutile (TiO₂) produce extremely pure linearly polarized light. Total Internal Reflection of p-pol. at the gap between the prisms while s-pol. is transmitted.
Double Glan-Taylor Polarizers	Calcite	p-pol. - 0° s-pol. absorbed by housing	No	No	Triple prism configuration and birefringent calcite produce maximum polarized field over a large half angle. Total Internal Reflection of s-pol. at the gap between the prism while p-pol. is transmitted.
Glan Thompson Polarizers	Calcite	p-pol. - 0° s-pol. absorbed by housing	No	No	Double prism configuration and birefringent calcite produce a polarizer with the widest field of view while maintaining a high extinction ratio. Total Internal Reflection of s-pol. at the gap between the prism while p-pol. is transmitted.
Wollaston Prisms and Wollaston Polarizers	Quartz, Magnesium Fluoride, α-BBO, Calcite, Yttrium Orthovanadate	Symmetric p-pol. and s-pol. deviation angle	No	No	Double prism configuration and birefringent calcite produce the widest deviation angle of beam displacing polarizers. s-pol. and p-pol. deviate symmetrically from the prism. Wollaston prisms are used in spectrometers and polarization analyzers.
Rochon Prisms	Magnesium Fluoride or Yttrium Orthovanadate	Ordinary Ray: 0° Extraordinary Ray: deviation angle	No	No	Double prism configuration and birefringent MgF₂ or YVO₄ produce a small deviation angle with a high extinction ratio. Extraordinary ray deviates from the input beam's optical axis, while ordinary ray does not deviate.
Beam Displacing Prisms	Calcite	2.7 or 4.0 mm Beam Displacement	No	No	Single prism configuration and birefringent calcite separate an input beam into two orthogonally polarized output beams. s-pol. and p-pol. are displaced by 2.7 or 4.0 mm. Beam displacing prisms can be used as polarizing beamsplitters where 90^o separation is not possible.
Fresnel Rhomb Retarders	N-BK7	Linear to circular polarization Vertical Offset	No	No	λ/4 Fresnel Rhomb Retarder turns a linear input into circularly polarized output. Uniform λ/4 retardance over a wider wavelength range compared to birefringent wave plates.
Fresnel Rhomb Retarders	N-BK7	Rotates linearly polarized light 90°	No	No	λ/2 Fresnel Rhomb Retarder rotates linearly polarized light 90°. Uniform λ/2 retardance over a wider wavelength range compared to birefringent wave plates.

S-polarized light is not pure and contains some P-polarized reflections.

Beamsplitter Prisms

Prism

Material

Deviation

Invert

Reverse or Rotate

Illustration

Applications

Beamsplitter Cubes

N-BK7

50:50 splitting ratio, 0° and 90°

s- and p- pol. within 10% of each other

Double prism configuration and dielectric coating provide 50:50 beamsplitting nearly independent of polarization.

Non-polarizing beamsplitter over the specified wavelength range.

Polarizing Beamsplitter Cubes

N-BK7, UV Fused Silica, or N-SF1

p-pol. - 0°

s-pol. - 90°

Double prism configuration and dielectric coating transmit p-pol. light and reflect s-pol. light.

For highest polarization use the transmitted beam.

Posted Comments:
Julien Roul (posted 2020-11-17 11:25:36.843) Hi, Do you have any information about the LIDT for the RPM10 ? Thanks Julien YLohia (posted 2020-11-20 10:44:56.0) Hello Julien, unfortunately, we have not performed LIDT tests on RPM10 as this is uncoated magnesium fluoride, the information for which can be found in literature.

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.

Wire Grid Polarizers

Film Polarizers

Beamsplitting Polarizers

alpha-BBO Polarizers

Calcite Polarizers

Quartz Polarizers

Magnesium Fluoride Polarizers

Yttrium Orthovanadate (YVO₄) Polarizers

Rutile Polarizers

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.
PBS519: Average T_P:T_S > 1000:1
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.

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Rochon Prisms

Features

Non-Polarizing Beamsplitters

Polarizing Beamsplitters

Other Beamsplitters

Selection Guide for Prisms

Beam Steering Prisms

Dispersive Prisms

Beam Manipulating Prisms

Polarization Altering Prisms

Beamsplitter Prisms

Polarizer Selection Guide