These beamsplitter cubes separate the “s” and “p” polarization components of a light beam. These two polarization components are reflected (“s”) and transmitted (“p”) respectively. Thus, both components are well separated (90°) and available for further use.
When non-polarized light is normally incident upon the entrance face, it is separated into two polarized beams, emerging through two adjacent faces in perpendicular directions and polarized orthogonally to each other.
When linearly polarized light is incident, it is similarly divided into two beams in a ratio depending upon the orientation of the polarization of the incident light beam.
Polarizing beamsplitter cubes are more economical than crystal polarizers, but do not achieve the very high extinction ratio of the crystal polarizers.
The acceptance angle of PBSCs is quite small. The specified extinction ratio is realized only with well collimated beams, usually a laser.
The beamsplitter cube consists of a pair of precision right-angle prisms carefully cemented together to minimize wavefront distortion and beam skewing. The hypotenuse of one prism is coated with a multilayer beamsplitter coating tuned to the application.
The four outside surfaces of the prism are anti-reflection (AR) coated with “V” type or broadband coatings to minimize surface reflection losses over the specific wavelength range.
PBSCs may be cemented for low power applications. This is economical and also allows broadband designs. For single wavelength, high power applications, the PBSC is optically contacted (cement free). This option is available up to a size of 25mm maximum.
|Range of dimensions||2mm – 75mm|
|Highest available extinction ratio (PER)||1500:1|
|Highest available surface figure||λ/10 (DIN: 3/0.2)|
|Highest available surface quality||20-10 S/D (DIN: 5/2×0.1)|
|Wavelength range||Single wavelength or broadband|
|Highest available tolerance of beam deviation||3″ (arcsec)|
|High power version for single wavelength||~10 J/cm² at 1064nm for 10nsec pulse|
In addition to custom products we offer a limited range of standard polarizing beamsplitter cubes for low volume applications. Details are available on the download tab.