Beamsplitters

Beam splitters separate a beam of light by wavelength, power, or polarization into two orthogonal beams. The properties of the divided beams depend both on the beam splitter coating and on the mechanical characteristics of the plate or cube upon which it has been coated. Here at CVI Laser Optics, we have combined our expertise in the manufacture of quality optics with our many optical coatings to create a broad range of beam splitters available off the shelf for the most common applications in research or prototyping.

We can also work with you one-on-one to develop custom beam splitters for a specific experiment or new product development. Our expert technical staff will guide you through the many options we offer, ranging from custom split ratios, unique materials, and custom coatings to unusually large or small dimensions. We understand that high laser damage threshold and beam displacement are important considerations when incorporating a beam splitter into a new optical design, and will work with you to navigate our options for beam splitter construction, coatings, and surface quality to strike the optimum balance between cost and performance. Beam splitter coatings can even be applied to our wedged and plane parallel substrates for OEM applications. High quality antireflection coatings are also available on all of our beam splitters to aid maximum throughput and power handling.

Capabilities

Standard Custom Options
Types Plate, cube
Materials N-BK7, UV-grade fused silica, crown glass, N-SF2 MgF2, CaF2, Suprasil 1, Infrasil 301, N-BAK1
Dimensions 10.0 to 76.2 mm 3 to 300 mm <
Coatings
  • Polarizing
  • Laser line non-polarizing
  • Laser line and broadband dielectric
  • Broadband hybrid
  • Wavelengths from 193 to 2100 nm
  • Fixed split ratios from 50:50 to 1:99
  • Extinction ratios up to 1000:1
  • Custom split ratios
  • Other wavelengths
  • Partially reflecting metal
  • Higher extinction ratios
Quality Standard, precision, and laser grade See manufacturing tolerances below
Construction (cubes)
  • Optical adhesive contacting
  • Chemically activated direct bonding
  • Optical contacting

Cube Beamsplitter Manufacturing Capabilities**

Surface Tolerances Precision Laser Quality High Precision
Surface quality (scratch - dig) 20 - 10 10 - 5 5 - 2
Surface roughness (Å, RMS) 20 5 2.5
Flat Irregularity, (P-V @ 633 nm before coating) λ/4 λ/10 λ/20
Dimensional Tolerances Standard Precision High Precision
Length & width (mm) +0.000 / -0.250 ± 0.150 +0.000 / -0.010
Thickness (mm) +0.000 / -0.250 ± 0.150 ± 0.005
Angular deviation < 3 arc min ≤ 10 arc sec ≤ 0.5 arc sec
Clear Aperture ≥ 85% ≥ 90% ≥ 95%

Plate Beamsplitter Manufacturing Capabilities**

Surface Tolerances Precision Laser Quality High Precision
Surface Quality (scratch - dig) 40 - 20 10 - 5 5 - 2
Surface roughness (Å, RMS) 20 5 1
Surface Figure (P-V @ 633 nm before coating) λ/2 λ/10 λ/25
Dimensional Tolerances Commercial Precision High Precision
Diameter (mm) +0.000 / -0.250 +0.000 / -0.100 +0.000 / -0.010
Length & width (mm) ± 0.050 +0.000 / -0.125 +0.000 / -0.010
Thickness (mm) ± 0.250 ± 0.100 ± 0.010
Angular deviation < 5 arc min ≤ 1 arc sec ≤ 0.5 arc sec
Centration (ETV, mm) 0.05 0.01 0.005
Clear Aperture ≥ 85% ≥ 90% ≥ 95%
Spherical Tolerances Commercial Precision High Precision
Spherical irregularity (P-V @ 633 nm before coating) λ/2 λ/5 λ/100
Spherical radius (fringes) 5 3 0.5

** Note: The general tolerance specifications above are intended to guide determination of appropriate tolerances based both on relative cost and manufacturability. Part-specific tolerances will vary depending on size, material, shape and aspect ratio. Tighter tolerances may be possible, so please contact us to discuss your custom specifications. All specifications do not need to be from a single column, though trade-offs may be required in order to meet the desired combination of cost and performance.