Polarizer

Optics >>> Polarizer

We supply a wide range of polarizers, including Glan Laser, Glan Taylor, Glan Thompson, Wollaston and Rochon by employing birefringent crystals: a-BBO, Calcite, YVO4 and quartz. The material properties of birefringent crystals are deciding factors in your selection of the right type polarizer.  

a-BBO (high temperature phase of BaB2O4) is characterized by large birefringent coefficient and wide transmission window from 189nm to 3500nm, particularly suitable for high power UV polarizer (200-300nm).

YVO4 crystal has been widely used in fiber optical components due to its large birefringence, good physical and favorable mechanical properties. Since the crystal has high transmission from 500 to 3500 nm, it is recommended to use YVO4 polarizer for IR (up to 4000nm) application.

Crystal quartz is a natural occurring as well as synthetically grown positive uniaxial crystal that is optical active, i.e. it rotates the plane of polarization of linearly polarized input beam traveling along the crystal optic axis. Because of it's reatively low birefringence, it is not feasible to fabricate a crystal quartz Glan type polarizer but as Rochon polarizer.

Calcite is a natural minded crystal and the most common crystals for polarizers used as visible and near IR polarizers. Defect in bulk calcite are characterized by bubbles, striae, optical inhomogeneity and stress birefringence. These defects cause degradation of polarization and transmission loss due to scattering and absorption. That is why the extinction of the polarizer is not as high as synthetically grown material YVO4, a-BBO and crystal quartz.



Calcite: T% vs Wavelength
 


a
-BBO: T% vs Wavelength


YVO4: T% vs Wavelength
 



Quartz: T% vs Wavelength
 

Table of Comparison:

YVO4
Calcite
a-BBO
Quartz
Transparency
400-5000nm
350-2300nm
189-3500nm
200-2300nm
Crystal class(Uniaxial)
Positive
no=na=nb,ne=nc
Negative
no=na=nb,ne=nc
Negative
no=na=nb,ne=nc
Positive
no=na=nb,ne=nc
Mohs hardness
5
3
4.5
7
Thermal Expansion Coefficient
aa=4.43x10-6/K
ac=11.37x10-6/K
aa=24.39x10-6/K
ac=5.68x10-6/K
aa=4x10-6/K
ac=36x10-6/K
aa=6.2x10-6/K
ac=10.7x10-6/K
Hygroscopic susceptibility
Low
Low to moisture
Low
Low

A polarizer is an important optical component that is widely used in laser systems to generate linear polarization laser. We supply following polarizers with a-BBO, Calcite or YVO4.  They are suitable for a wide range of spectrums and high polarization purity applications.

Polarizer

Material

Illustration

Properties and Application

Glan-Taylor Polarizer

a-BBO
(190-3500nm)
Calcite
(350-2300nm)
YVO4
(500-5000nm)


a-BBO

  Air-spaced
  Close to Brewster's Angle Cutting.
  Low L/A=0.8
  Mounted without escape windows.
  For low to medium power application.

Glan-Laser Polarizer

a- BBO
(190-3500nm)
Calcite
(350-2300nm)
YVO4
(500-5000nm)

a-BBO

  Air Spaced.
  Close to Brewster's angle Cutting.
  Mounted with escape windows.
  Suitable for high power applications.
  L/A=1.5

Glan-Thompson Polarizer

a- BBO
(220-900nm)
Calcite
(350-2300nm)

a-BBO

Cemented.
Suitable for low power applications.
Wide acceptance angle.

Wollaston Polarizer

a- BBO
(200-3500nm)
Calcite
(350-2300nm)
YVO4
(400-4000nm)
Quartz
(200-2300nm)

a-BBO

Cemented.
Separate ordinary and extraordinary beams at certain angle.
Suitable for low power application and where the large deviation is required

Glan-Thompson Polarizer Beamsplitter Cube

a- BBO
(200-3500nm)
Calcite
(350-2300nm)
YVO4
(400-4000nm)
Quartz
(200-2300nm)

a-BBO

Cemented.
Separate ordinary and extraordinary beams at certain angle.
Suitable for low power application and where the large deviation is required

Rochon Polarizer

a-BBO
(200-3500nm)
YVO4
(400-4000nm)
Quartz
(200-2300nm)

a-BBO

a-BBO is used to guarantee a wide transmission range.
Especially, suitable for UV application.
Split the ordinary and extraordinary ray, but only ordinary beam is deviated

Polarization Beamsplitter

BK7 Grade A Optical Glass
or
SF5 Optical
Glass

Split the ordinary and extraordinary ray. The ordinary beam is deviated 90.  For detailed information, refer to Beamsplitter.

There are many types of prism, each having a particular geometry, used to achieve the reflections required to perform a specific imaging task. Reflecting prisms may invert, rotate, deviate or displace a beam.  Dispersing prisms produce spectral separation for spectroscopic applications or tuning a laser output.

Red Optronics provides all kinds of high precision prisms, including Penta Prism, Beamsplitter Penta Prism, Right Angle Prism, and Corner Cube. Our micro Penta Prism and Right Angle Prism are widely used in optical communication, such as optical switches.  

 

 

 

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