Description
LBO crystals (Lithium Triborate (LiB3O5 or LBO))
LBO crystals is an excellent nonlinear crystal. For frequency doubling(SHG),tripling(THG) of Nd:YAG,Nd:YLF,Nd:YVO4 lasers, it is one of the most useful nonlinear optical materials in ultraviolet and visible laser applications.
Advantages:
• broad transparency range from 160nm to 2600nm (see Figure 1);
• high optical homogeneity (δn≈10-6/cm) and being free of inclusion;
• relatively large effective SHG coefficient (about three times that of KDP);
• wide acceptance angle and small walk-off;
• type I and type II non-critical phase matching (NCPM) in a wide wavelength range;
• spectral NCPM near 1300nm.
• high damage threshold(18.9 GW/cm 2 for a 1.3ns laser at 1053nm);
LBO has the highest damage threshold in all the commonly-used inorganic NLO crystals. Therefore, it is the best candidate for high average power SHG and other nonlinear optical processes.
Basic Properties:
|
Crystal Structure |
Orthorhombic, Space group Pna21, Point group mm2 |
|
Lattice Parameter |
a=8.4473Å,b=7.3788Å,c=5.1395Å,Z=2 |
|
Melting Point |
About 834℃ |
|
Mohs Hardness |
6 |
|
Density |
2.47g/cm3 |
|
Thermal Expansion Coeficients |
αx=10.8x10-5/K, αy=-8.8x10-5/K,αz=3.4x10-5/K |
|
Thermal Conductivity Coefficients |
3.5W/m/K |
|
Transparency Range |
160-2600nm |
|
SHG Phase Matchable Range |
551-2600nm (Type I) 790-2150nm (Type II) |
|
Therm-optic Coefficient (/℃, λ in μm) |
dnx/dT=-9.3X10-6 dny/dT=-13.6X10-6 dnz/dT=(-6.3-2.1λ)X10-6 |
|
Absorption Coefficients |
<0.1%/cm at 1064nm <0.3%/cm at 532nm |
|
Angle Acceptance |
6.54mrad·cm (φ, Type I,1064 SHG) 15.27mrad·cm (θ, Type II,1064 SHG) |
|
Temperature Acceptance |
4.7℃·cm (Type I, 1064 SHG) 7.5℃·cm (Type II, 1064 SHG) |
|
Spectral Acceptance |
1.0nm·cm (Type I, 1064 SHG) 1.3nm·cm (Type II, 1064 SHG) |
|
Walk-off Angle |
0.60° (Type I 1064 SHG) 0.12° (Type II 1064 SHG) |
