Lithium Fluoride, LiF crystal
LiF crystal shows excellent transmittance in the VUV region. It is used for optical windows, prisms, and lenses in the visible and infrared in 0.104 μm - 7 μm. LiF crystal is sensitive to thermal shock and would be attacked by atmospheric moisture at 400°C. In addition irradiation produces color centers. Modest precautions should be taken against moisture and high energy radiation damage. Besides LiF softens at 600°C and is slightly plastic that can be bent into radius plates. The material can be cleaved along (100) and less commonly (110). Although the optical characteristics are good, the structure is not perfect and cleavage is difficult. For good structure LiF is less commonly grown by the Kyropoulos technique (air-grown) specifically for monochromator plates. High quality LiF is usually grown by modified Bridgman technique. Maximum available size in diameters is about 115mm. LiF is slightly plastic and can be bent into radius plates.
LiF crystals have the following exceptional properties that make it a very important optics single crystal:
(1) High optical transmittance from the vacuum ultraviolet to the infrared spectrum region(0.12-6μm) and shows excellent transmittance in the VUV regions.
(2) Used for Optical prisms, lenses, wedges, windows, other optical components,and etc
Because of its particular lattice structure LiF can also be used as X-ray diffraction devices.
LiF Specifications:
We produce granules, prisms, lenses, wedges, windows and other optical components according to requested specifications and drawings.
Size: Diameter >60mm
Size tolerance: +/-0.1mm
Angle tolerance: +/- 10 arcand Specifications
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Transmission Range (μm)
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0.12 ~ 6
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Refractive Index at 0.6 μm
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1.39181
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Reflection Loss at 0.6 μm
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5.2% (2 surfaces)
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Absorption Coefficient at 2.7μm (cm-1)
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0.74×10-3
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Transmission range (μm)
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0.11~7.0
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Density (g/cm3)
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2.639
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Melting Point (°C)
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870
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Molecular Weight
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25.9394
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Thermal Conductivity at 314K (Wm</-1K-1)
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4.01
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Thermal Expansion at 283K (K-1)
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37×10-6
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Knops Hardness
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99.1–103kg/mm2
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Specific Heat Capacity (J Kgm-1K-1)
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1562
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Elastic Coefficient
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C11=112; C12=46; C44= 63.5
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Apparent Elastic Limit
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11.2 Mpa (1620 psi)
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Poisson Ratio
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0.326
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Solubility in 100g water at 20°C (g)
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0.27
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Crystal orientation
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(100)
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Application
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DUV, Vacuum UV
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Wavelength (nm)
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150
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193
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248
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308
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400
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600
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800
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Refractive index
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1.4990
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1.4477
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1.4182
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1.4083
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1.3992
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1.3918
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1.3889
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Wavelength (nm)
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1000
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2000
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3000
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4000
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5000
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6000
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7000
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Refractive index
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1.3871
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1.3787
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1.3666
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1.3494
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1.3266
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1.2974
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1.2556
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| specification︰ | We produce granules, prisms, lenses, wedges, windows and other optical components according to requested specifications and drawings. |
| advantage︰ | high quality, quickly delivery time |
| Minimum Order︰ | 1 |
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