Nonlinear Optical Crystals: LBO

LBO crystals (Lithium Triborate Crystal) 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.

Comparison of Bulk Damage Threshold (@1053nm ,1.3ns)
Crystal	Energy Density (J/cm 2 )	Power Density (GW/cm 2 )	Ratio
KTP KDP BBO LBO	6.0 10.9 12.9 24.6	4.6 8.4 9.9 18.9	1.00 1.83 2.15 4.10

LBO’s main applications

• SHG, THG of Nd lasers
• SHG of Ti:Sapphire, Cr:LiSAF and Alexandrite lasers
• OPA and OPO

We offer LBO specification:

Tolerance of cutting angle	△θ≤±0.25°,△φ≤±0.25°
Tolerance of dimension	Dimension+/-0.1 mm，L：±0.1mm
Flatness	λ/8 @ 632.8nm
Wavefront distortion	λ/8@ 632.8nm
Surface quality	10/5  per MIL-O-13830A
Parallelism	10″
Perpendicularity	5′
Bevel/chamfer	<0.1mm@45deg.
Chips	<0.1mm
CA	>95%
Coating	AR/P-coating Upon customer’s request
Damage Threshold	750MW/CM2 at 1064nm, TEM00, 10ns, 10Hz
Warranty	One year under proper use