Calcium Fluoride(CaF2) Double-Concave Lenses
Calcium fluoride (CaF2) double concave lens, with high hardness, strong resistance to mechanical shock and thermal shock, and good transmittance in UV, visible and infrared fields, are widely used in scientific and technological fields such as lasers, infrared optics, UV optics and high-energy detectors, especially they have good optical properties in the UV band. With high transmittance and low fluorescence radiation, calcium fluoride double concave lens is an ideal material for UV photodetectors, UV lasers and UV optical systems.
Calcium fluoride (CaF2) biconcave lens is similar to a plano-concave lens in that the focal length is negative, but the light incident in parallel diverges outward, and is often used for optical instruments,laser optical systems, infrared optical systems, telecommunication, such as telescopes, microscopes, cameras, satellite optical systems, space telescopes, lasers device, laser LiDAR,medical imaging system Etc.
Our company can provide Calcium fluoride (CaF2) double concave lens with diameters from 2-300mm.and thicknesses from 0.12-60mm (accuracy up to 20-10, 1/10L@633nm),coating AR, BBAR, AF or upon request.
Technical parameters of CaF2 Double-Concave Lens
Diameter | 2-300mm |
Focal length | 15-5000mm |
Thicknesses | 0.12-60mm |
Dimension tolerance | +0/-0.1mm |
Thickness tolerance | ±0.1mm |
Surface quality (scratch & dig) | 60-40, 40-20, or better |
Surface accuracy | λ/2, λ/4 or better |
Parallelism | 3' ,30'' |
Bevel | 0.1~0.3mm x 45 degree |
Clear aperture | >85%,>90% |
Coating | AR coating or cutom |
Material properties of CaF2
Optical Properties | |
Transmission Range | 0.13-10μm |
Transmittance | >94%@193nm-7.87μm |
Refractive Index | 1.4288@2.5μm |
1.39908@5μm | |
Reflection Loss | 5.4%@5μm(both surfaces) |
Absorption Coefficienet | 7.8×10-4@2.7μm |
Structure | Cubic Crystal System |
Cleavage Planes | <111> |
Physical Properties | |
Density[g/cm3] | 3.18 |
Melting Point [℃] | 1420 |
ThermalConductivity [W/(m×K)] | 9.71 @ 293K |
Thermal Expansion [10-6/K] | 18.5 @ 273K |
Knoop Hardness [kg/mm2] | 158.3 |
Specific Heat Capacity [J/(kg×K)] | 854 |
Dielectric Constant | 6.76 @ 1 MHz |
Young's Modulus (E) [GPa] | 75.8 |
Shear Modulus(G) [GPa] | 33.77 |
Bulk modulus(K) [GPa] | 82.71 |
Poisson Coefficient | 0.26 |
Chemical Properties | |
Solubility / g/L | 0.016g @ 20℃ |
Molecular Weight / g/mol | 78.0748 |
Transmission curve
The transmission spectrum of calcium fluoride (CaF2) ranges from 130 nm to 10 μm. High hardness, strong resistance to mechanical and thermal shocks, and good transmittance of calcium fluoride (CaF2) plano convex in the UV, visible and IR fields are widely used in scientific and technological fields such as lasers, IR optics, UV optics and high-energy detectors, especially they have good optical properties in the UV band and are the known optical properties in the UV cut-off band. With high transmittance and low fluorescence radiation, calcium fluoride is an ideal material for UV photodetectors, UV lasers and UV optical systems.