Polarizing Beam Splitters

Cube Beam Splitter
Plate Beam Splitter

Part Number	Wavelength(nm)	Material	Diameter(mm)	Thickness (mm)	Angle of Incidence (°)
BSPP-266-45-1	266	Fused Silica	25.4	6.35	45
BSPP-266-45-2	266	Fused Silica	50.8	6.35	45
BSPP-355-45-1	355	Fused Silica	25.4	6.35	45
BSPP-355-45-2	355	Fused Silica	50.8	6.35	45
BSPP-532-45-1	532	Fused Silica	25.4	6.35	45
BSPP-532-45-2	532	Fused Silica	50.8	6.35	45
BSPP-980-45-1	980	Fused Silica	25.4	6.35	45
BSPP-980-45-2	980	Fused Silica	50.8	6.35	45
BSPP-1064-45-1	1064	Fused Silica	25.4	6.35	45
BSPP-1064-45-2	1064	Fused Silica	50.8	6.35	45
BSPP-266-B-1	266	Fused Silica	25.4	3.00	Brewster's
BSPP-266-B-2	266	Fused Silica	50.8	3.00	Brewster's
BSPP-355-B-1	355	Fused Silica	25.4	3.00	Brewster's
BSPP-355-B-2	355	Fused Silica	50.8	3.00	Brewster's
BSPP-532-B-1	532	N-BK7	25.4	3.00	Brewster's
BSPP-1064-B-1	1064	N-BK7	25.4	3.00	Brewster's
BSPC-266-1	266	Fused Silica	25.4 x 25.4 x 25.4	-	-
BSPC-355-1	355	Fused Silica	25.4 x 25.4 x 25.4	-	-
BSPC-VIS-1	420-680	N-SF1	25.4 x 25.4 x 25.4	-	-
BSPC-VIS-2	420-680	N-SF1	50.8 x 50.8 x 50.8	-	-
BSPC-NIR-1	640-900	N-SF1	25.4 x 25.4 x 25.4	-	-

Plate Beam Splitter - BSPP series

BSPP series polarizers split light into two beams and transmits the p-polarized beam while reflects the s-polarized beam. The 45° angle of incidence makes mounting easier for optics comparing at Brewster’s angle of incidence. Due to the AR coating onto the surface, there is a high damage threshold that makes it useful for high optical power applications. Plate beam splitter polarizers are also used in photonics instrumentation, optical isolation and in many other applications.

Plate Beam Splitter Polarizers are available with us in several wavelength ranges, desired wavelengths, shapes, sizes plus incidence angles and we can also make customer specifications.

Cube Beam Splitter - BSPC series

Two right-angled prisms are put together by each hypotenuse respectively with the help of cement or optical contact to form a Cube Beam Splitter Polarizer. When an unpolarized light falls on the cube beam splitter polarizer, it separates input light into two polarization components and reflects the s-component of polarization. Optical power tolerance is higher when the two prisms of the cube beam splitter are in optical contact thus usable for high power applications. It is used in applications where the simplified mounting and system integration is an important aspect. It is also used in the applications for imaging systems.

Our company offers Cube Beam Splitter Polarizer for a wide range of wavelengths (UV-NIR) in different dimensions for optimized performances. A customized Cube Beam Splitter Polarizer can be manufactured based on our customer requirements.

Plate Beam Splitter Polarizer - BSPP series

Material: Fused Silica, N-BK7
Wavelength: 380-2100nm (N-BK7) | 200-2100nm (Fused Silica)
Angle Of Incidence: @ 45°, Brewster’s angle
Extinction Ratio: T_p/T_s > 200:1
Surface Quality: 60/40 scratch and dig
Thickness: 3mm
Dimension: 0.5", 1" & 2"
Dimension Tolerance: +0.0/-0.2mm
Thickness Tolerance: ±0.25mm
Damage Threshold: >5J/cm², 20ns, 20Hz @ 1064nm

Cube Beam Splitter Polarizer - BSPC series

Material: Fused Silica, N-BK7, N-SF1
Wavelength: 380-2100nm (N-BK7) | 195-2100nm (Fused Silica) | 420-680nm (N-SF1)
Surface Contact Type: Cemented, Optically Contacted
Extinction Ratio: Tp/Ts > 1000:1 (Narrow Band) | >100:1/>1000:1 (Broad Band)
Surface Quality: 60/40 scratch and dig | 40/20 scratch and dig
Dimension: 0.5", 1" & 2"
Dimension Tolerance: ±0.2mm
Damage Threshold: >500mJ/cm² for cemented| >5J/cm²

for optically contact, 20ns, 20Hz @ 1064nm

Plate Beam Splitter Polarizer - BSPP series

Cube Beam Splitter Polarizer - BSPC series

Variable Beam Splitter: Precision Control by The Principle of Polarization Application Note

Precision laser applications require fine power control. A variable beam splitter with a large dynamic range and precision control is designed to fulfill this purpose. It is suitable for intensity splitting between two polarization states over a wavelength range from UV to IR.

Operation Principle

This variable beam splitter consists of a specially designed precision optomechanical holder. The key optics involved include a half-wave plate and polarization beam splitter (PBS). The half-wave plate is usually made of birefringent crystal cut parallel to the optical axis. It is used to change the polarization direction of the incident beam. The surfaces of the waveplate and the beamsplitter cube are coated with an AR-coating over the designed wavelength range. The PBS placed after the half-wave plate reflects s-polarized light while transmitting p-polarized light. The intensity ratio of s-polarized to p-polarized beams may be continuously varied by rotating the wave plate. The intensity of either the exit beam or their intensity ratio can be controlled over a wide dynamic range. P-polarization can be selected for maximum transmission. A full range of intensity variation between the two beams from maximum to minimum can be achieved by rotating the half-wave plate from 0 to 45 degrees.

Figure 1. Principle of the variable beam splitter

Figure 2. The layout of the variable beam splitter

The key specifications of the variable beam splitters at different operating wavelengths are listed below.

Wavelength	355/532/1064nm
Type	Transmission Mode
Clear Aperture	14mm
Beam Shift	0.5mm
Extinction Ratio	>200:1
Power Variation Range	0.5% – 95%
Damage Threshold	>5J/cm2@1064nm, 20ns, 20Hz
Weight	<300g

Table 1. Key specifications of polarization attenuator

Applications

The following listed characteristics enable the variable beam splitter to precisely control the laser intensity with fine adjustment steps. Using a suitable type of polarizer, this principle can be realized at very high-power levels.

Divides laser beam into two parallel beams of the manually adjustable intensity ratio
Large dynamic range
Negligible transmitted beam deviation
High optical damage threshold
Transmission attenuation range 0.5% – 95.0%