Monocrystalline(Single Crystal )&Polycrystalline Infrared CaF2/BaF2/LiF Optical Windows/lens
CaF2 crystal have good performance at 0.13~10 μm wavelength range, wide range of light.CaF2 cyrstal is transparent over a broad range from ultraviolet (UV) to infrared (IR) frequencies.CaF2 is used to manufacture optical components such as windows and lenses, used in thermal imaging systems, spectroscopy, and excimer lasers, Fourier analysis, testing instruments, gas liquid laser system, astronomical telescope, MIR/NIR imaging system, etc.
BaF2 (Barium Flouride)
BaF2 is transparent from the ultraviolet to the infrared, from 150-200nm to 11-11.5μm, and can be used as a material to make optical components such as lenses. It is used in windows for infrared spectroscopy, in particular in the field of fuel oil analysis. Its transmittance at 200nm is relatively low (0.60), but at 500nm it goes up to 0.96-0.97 and stays at that level until 9μm, then it starts falling off (0.85 for 10μm and 0.42 for 12μm). The refractive index is about 1.46 from 700nm to 5μm. Barium Flouride is used as a preopacifying agent and in enamel and glazing frits production. It is also used in metallurgy, as molten bath for refining aluminum.
MgF2 (Magesium Flouride is transparent over a extremely wide range of wavelengths .windows, lenses ,and prisms made of this materials can be used over the entire range of wavelengths from 0.12μm(vacuum ultraviolet ) to 8.0μm (infrared). High quality synthetic VUV grade MgF2 is quite expensive. Low grade MgF2 is sometimes used in the infrared but it is inferior to CaF2. MgF2 is tough and works and polishes well, but it is slightly birefringent and should be cut with the optic axis perpendicular to the plane of the window or lens.
Optical window materials comparison:
||+0.1, -0.1 mm
||+0.1, -0.1 mm
||±30 Arc Seconds
||1/4 L @632.8nm
||60-40 scratch and dig
||0.25 mm X 45°
||As customer's requirements