WPBS254-VIS

• Polarizing beamsplitter design for separating light according to polarization state.
• 400–700 nm design wavelength range for visible-light applications.
• High transmitted-beam extinction ratio: >1,000:1 at 0–5° AOI.
• Maintains >100:1 extinction ratio over a broader 0–25° angle-of-incidence range.
• Transmits P-polarized light while primarily reflecting S-polarized light.
• High P-polarized transmission: >75% average at 0° AOI across 400–700 nm.
• High S-polarized reflectance: >70% from 400–700 nm over 0–25° AOI.
• Constructed from N-BK7 optical glass with an integrated wire-grid polarizing layer.
• Ø22.9 mm × 22.9 mm minimum clear aperture for large beam applications.
• 1" (25.4 mm) cube dimensions for convenient integration into standard optical systems.
• Broad acceptance angle compared with conventional broadband polarizing beamsplitter cubes.
• Suitable for polarization separation, beam routing, and visible-wavelength optical systems.

The Thorlabs WPBS254-VIS is a 1" wire grid polarizing beamsplitter cube designed to separate the orthogonal polarization components of visible light over the 400–700 nm wavelength range.

The beamsplitter consists of a fine array of parallel metallic wires positioned between two N-BK7 prisms. The wire-grid structure selectively transmits light whose electric-field vector is perpendicular to the wires while reflecting light whose electric-field vector is parallel to the wires. As a result, the cube can be used to separate P-polarized and S-polarized components into different optical paths.

One of the key advantages of the WPBS254-VIS is its high extinction ratio for the transmitted beam. At an angle of incidence from 0° to 5°, the transmitted P-to-S ratio is greater than 1,000:1. Even at higher angles of incidence from 5° to 25°, the extinction ratio remains greater than 100:1, making the cube suitable for optical systems requiring a relatively broad range of incident angles.

The four outer optical surfaces are BBAR coated for 400–700 nm, with an average reflectance of less than 0.5% at 0° AOI. The transmitted beam has an average P-polarized transmission greater than 75%, while the S-polarized reflectance is greater than 70% over the specified wavelength and AOI ranges.

With a 25.4 mm cube size and a clear aperture greater than 22.9 mm × 22.9 mm, the WPBS254-VIS is well suited for visible-wavelength systems requiring polarization separation with a relatively large optical aperture.

Product Type: Wire Grid Polarizing Beamsplitter Cube
Part Number: WPBS254-VIS
Design Wavelength Range: 400–700 nm
Substrate Material: N-BK7
Beamsplitter Type: Wire Grid Polarizing
Polarization Function: Transmits P-polarized; reflects S-polarized
Extinction Ratio (Transmitted Beam): Tp >1,000:1 @ 0–5° AOI
Extinction Ratio (Transmitted Beam): Tp >100:1 @ 0–25° AOI
P-Polarized Transmission: Tp >75% Avg. at 0° AOI, 400–700 nm
S-Polarized Reflectance: Rs >70% @ 0–25° AOI, 400–700 nm
AR Coating: BBAR, Ravg < 0.5% at 0° AOI, 400–700 nm
Clear Aperture: >22.9 mm × 22.9 mm
Cube Dimensions: 25.4 mm × 25.4 mm × 25.4 mm
Transmitted Beam Deviation: <5 arcmin
Reflected Beam Deviation: 90° ±5 arcmin
Transmitted Wavefront Error: <λ/4 @ 633 nm
Surface Quality—Four Side Faces: 40-20 Scratch-Dig
Surface Quality—Hypotenuse: 80-50 Scratch-Dig
Dimensional Tolerance: +0.00 / -0.25 mm

The extinction ratio is defined as the ratio of maximum to minimum transmission for a sufficiently linearly polarized input. The highest extinction ratio is achieved when the incident beam is within the 0–5° AOI range.

The WPBS254-VIS is suitable for a wide range of visible-wavelength polarization and photonics applications, including:

• Polarization Separation
• Polarizing Beam Splitting
• Laser Polarization Control
• Polarization Analysis
• Laser Beam Routing
• Interferometry
• Microscopy
• Spectroscopy
• Imaging Systems
• Optical Metrology
• Laser Beam Characterization
• Free-Space Optical Systems
• Quantum Optics Experiments
• Visible-Wavelength Photonics
• Scientific and Research Optical Setups

The WPBS254-VIS is particularly useful when an optical system needs to separate P- and S-polarized components into different beam paths while maintaining a high extinction ratio and accepting a relatively broad range of incident angles. Its large clear aperture also makes it suitable for systems using comparatively large visible-wavelength beams.