Calcium Fluoride crystal shows good optical and thermo-mechanical properties, can be used for optical INF-WINdows, lenses, prisms within a wide range from 130nm to 9μm. It has optical properties of isotropy, low absorption and low refractive index, which made CaF2 gain the unique advantages in the application of high power lasers.

INFAST offer:

CaF2 IR viewport windows for Infrared Thermography at 8μm to 10μm
Various optics for IR & VUV application, using our CaF2 crystal materials
Good quality CaF2 crystal blank materials
OEM service for good quality CaF2 crystals

Optical Properties

Transmission Range 130 nm to 10 μm

Transmittance >94% at 193 nm to 7.8 μm

Refractive Index 1.39908 at 5 μm

Reflection Loss 5.4% at 5 μm (both surfaces)

Absorption Coefficient 0.03 cm-1 at 2.6 μm to 2.9 μm

dn/dT -10.6 x 10-6 /℃

Physical Properties

Density 3.18 g/cm3

Melting Point 1360℃

Thermal Conductivity 9.71 Wm-1K-1 at 286K

Thermal Expansion 18.85 x 10-6 /℃ at 273K

Knoop Hardness 158.3 with 100g indenter (kg/mm2)

Specific Heat Capacity 854 J/(kg.k)

Dielectric Constant 6.76 at 1MHz

Youngs Modulus (E) 75.80 GPa

Shear Modulus (G) 33.77 GPa

Bulk Modulus (K) 82.71 GPa

Elastic Coefficient C11=164; C12=53; C44=33.7

Apparent Elastic Limit 36.54 MPa (3900 psi)

Poisson Ratio 0.26

Chemical Properties

Solubility 0.0017 g/ 100g water at 20℃

Molecular Weight 78.08

Structure Cubic Crystal

Cleavage Plane (111)

Specifications:

Material: Calcium Fluoride single crystal 
Diameter Tolerance: +0.0, -0.1mm
Thickness Tolerance:±0.2mm 
Clear Aperture: >80% 
Parallelism: 1 arc minute 
Flatness:λ/2 @ 632.8 nm 
Surface quality: 80/50 for general and 40/20 scratch and dig  for high precision

Protective Bevel: <0.25x45deg

Custom designs for other sizes and coatings are also available upon request.