CaF₂ Optical Prisms

Calcium fluoride prisms for broadband UV-IR applications including spectroscopy, ultrafast pulse compression, beam steering and polarization control. Available in equilateral, dispersing, Glan-Taylor, Glan-Laser and Wollaston configurations.

Key Specifications

Material	Calcium Fluoride (CaF₂)
Transmission Range	130 – 10,000 nm
Prism Types	Equilateral, Dispersing, Glan-Taylor, Glan-Laser, Wollaston
Apex Angle	30° / 45° / 60° / 90° / Custom
Angle Tolerance	± 2 arc-min (standard) / ± 30 arc-sec (precision)
Surface Quality	20-10 / 10-5
Size Range	5mm – 50mm face width
Coating	AR @ specific wavelength / Uncoated
Extinction Ratio	> 10⁵:1 (polarizing prisms)
Clear Aperture	≥ 90%

Material Options

Select the optimal optical material based on your wavelength, power, thermal environment and mechanical requirements.

Optical grade CaF₂ — Standard for spectroscopy and beam steering prisms.
UV grade CaF₂ — For excimer and deep UV applications where absorption must be minimized.

Available Optical Materials

Select the optimal substrate material based on your wavelength, environment, and budget requirements.

Material	Transmission	Key Advantage	Considerations
CaF₂ (Calcium Fluoride)	Deep UV / VIS / IR (130-7800nm)	Broadest transmission range, low refractive index	Fragile, hygroscopic, higher cost
N-BK7	VIS / NIR (350-2000nm)	General-purpose, low cost, good homogeneity	Not suitable for UV < 350nm
UV Fused Silica	UV / VIS / NIR (185-2100nm)	Excellent UV transmission, high laser damage threshold	Higher cost than BK7
Sapphire	UV / VIS / NIR (150-5500nm)	Extremely hard (9H), scratch resistant	Birefringent, higher refractive index

Not sure which material to choose?

Ask AI Optical Engineer

Coating Options

Coatings are engineered around your specific wavelength and operating conditions.

AR @ 355nm — R < 0.1% per surface. For UV laser beam steering.
AR broadband 200–1100nm — R < 0.5%. For spectroscopy and multi-wavelength systems.
Uncoated — ~3.2% per surface. Often used in spectroscopy where broadband performance matters more than throughput.

Manufacturing Tolerances

We optimize specifications to match your system requirements — not over-specify. Tighter tolerances increase cost without always improving system performance. Our engineers will work with you to identify which parameters actually matter for your application and where standard tolerances are sufficient. Typical manufacturing capabilities:

Surface quality: from 60-40 to 10-5 scratch-dig
Surface flatness: from λ/4 to λ/20 per inch
Dimensional tolerance: ±0.01mm to ±0.05mm
Centration: <3 arc min standard, <30 arc sec precision

Inspection & Quality

Every component undergoes 100% inspection before shipment. We provide full inspection documentation including interferometer reports, spectral transmission curves, surface quality images and dimensional measurement data. Equipment capabilities:

Laser interferometry: λ/100 resolution for flatness and wavefront
Spectrophotometry: 190nm – 25μm transmission and reflection
Surface inspection: MIL-PRF-13830B compliant
Dimensional metrology: ±0.01mm accuracy

Applications

UV-VIS-IR spectroscopy (dispersion and beam steering)
Ultrafast laser pulse compression (CaF2 pair prisms)
Polarization control (Glan-Taylor, Glan-Laser, Wollaston)
Excimer laser beam delivery
Raman spectroscopy optical paths
Fluorescence microscopy excitation/detection

Engineering Considerations

Dispersion characteristics: CaF₂ has lower dispersion than BK7, making it ideal for applications where chromatic effects must be minimized. For ultrafast pulse compression, CaF2 prism pairs provide adjustable group delay dispersion in the UV-NIR range.

Polarizing prism selection: Glan-Taylor prisms offer the best extinction ratio (>10⁵:1) with a separated rejected beam. Glan-Laser prisms are optimized for high-power laser use with total internal reflection dump. Wollaston prisms split into two diverging beams for interferometry.

Mechanical considerations: CaF₂ has cleavage planes — avoid mounting with point loads or uneven pressure. Use kinematic mounts with padded contacts.

Engineering Documentation

The following documentation is available upon request for qualified engineering projects:

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Dimensional Drawing

CAD & dimensional specs per your requirements

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Material Data Sheet

Material properties, transmission curves & certificates

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Coating Performance Curve

Spectrophotometric measurement data

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Inspection Report

Surface quality, flatness, centration & dimensional data

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Certificate of Conformance

CoC with full traceability per project requirements

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Custom Specification Sheet

Application-specific specification documentation

Documentation availability depends on project scope and order quantity. Request details during RFQ.

Frequently Asked Questions

What is the difference between Glan-Taylor and Glan-Laser prisms?

Both are CaF2 polarizing prisms. Glan-Taylor separates s- and p-polarizations spatially with the rejected beam dumped through total internal reflection. Glan-Laser uses the same geometry but is optimized for high-power lasers — the rejected beam is totally internally reflected out of the beam path without absorption. For powers >1W, choose Glan-Laser.

Can CaF2 prisms be used for femtosecond pulse compression?

Yes. CaF2 prism pairs are one of the standard methods for controlling group delay dispersion in femtosecond laser oscillers and amplifiers. The broad transparency of CaF2 (130nm–10µm) makes it suitable from UV to NIR ultrafast systems.

What apex angle should I choose for a dispersing prism?

60° (equilateral) is the most common for general spectroscopy. For higher dispersion, use larger apex angles (70–90°). For minimum deviation at a specific wavelength, calculate the optimal angle based on the refractive index at that wavelength.