Optical Crystal

Sapphire is a single crystal aluminum oxide(AL2O3).It is one of the hardest materials .Sapphire has good transmission characteristics over the visible,and near IR spectrum.It exhibits high mechanical strength,chemical resistance,thermal conductivity and thermal stability.It is often used as window material in specific field such as space technology where scratch or high temperature resistance is required.

crystal birefringent YVO4

Product introduction

Sapphire

Sapphire is a single crystal aluminum oxide(AL2O3). It is one of the hardest materials. Sapphire has good transmission characteristics over the visible, and near IR spectrum. It exhibits high mechanical strength, chemical resistance,thermal conductivity and thermal stability. It is often used as window material in specific field such as space technology where scratch or high temperature resistance is required.

Physical Properties

Crystal Symmetry Hexagonal	System
Lattice Constant	a=4.75;c=12.97
Transparence Range	0.18-4.5um
Density	3.98g/cm³
Mohs Hardness	9
Melting Point	2030℃
Thermal Conductivity	0.04W/m/k
Expansion Coefficient	8.4*10-6/k
Refractive Index	1.755

Silicon(si) Crystals

Silicon(Si) is commonly used as a substrate material for infrared reflectors and windows in the 1.5um-8um region.The strong absorption band at 9um makes it unsuitable for CO2 laser transmission applications but it is frequently used for laser mirrors because of its high thermal conductivity and low density.Silicon is also a useful transmitter in 20um range.

Material Type	CZ FZ;N or P
Crystal Direction	{100}{111}
Resistivity (Ohm/cm)	0.003-50
Thermal conductivity(J/K.M.S)	163.3@273K
Density	2.33g/cm³ at20℃
Melting point	1410℃
Boiling point	3265℃
Knoop Hardness	1150
Transparency Range	1000nm-10000nm，30000nm-300000nm