Undoped yttrium aluminum garnet (YAG) is an optical material similar to sapphire. Undoped YAG is widely used in UV and IR optics due to its mechanical and chemical characteristics.
Unlike other optical glasses with the tendency of absorption owing to strong water molecule bonds, undoped YAG carries no absorption lines in the range of 2-3 μm and can be applied in wide spectral range from 250 to 4000 μm.
High values of durability, thermal conductivity, damage threshold and the absence of birefringence allow undoped YAG to be successfully employed in applications pertaining to aggressive external impact and sensitive to optical distortion, including high temperature utilization and high-power laser usage.
Linear defects deficiency and high material homogeneity of Monocrystal undoped YAG crystals enable to produce polished windows, optical waveguides, prisms and other optical items with clear aperture up to 8".
Yttrium Aluminum Garnet (YAG): Zero-birefringence and High Thermal Conductivity
Properties of yttrium aluminum garnet
|Orientation|| or |
|Melting point||1950 °C|
|Mohs scale hardness||8 - 8,5|
|Density||4,55 g/cm 3|
|Thermal conductivity||0,14 W/ cm°C|
|dn/dt||7,4 х 10 -6 ° С -1|
|Thermal expansion||6,9 х 10 -6 ° С -1|
|Index of refraction
|Damage threshold||> 15 J/cm 2|
|Wavefront distortion||< l / 2|
|Diameter tolerance||+/- 0,05 mm|
|Flatness||< l/10 at 633 nm|
|Scratch-dig (per MIL-O-13830A)||10-5|