Lithium Tri-borate or LBO crystal is widely used broad optical transparency nonlinear optical material. Compared with other NLO crystals, such as KDP, LBO has 3 times larger conversion coefficient. It is suitable for  high power SHG applications because of minimal thermal lensing as compared to KTP.

  • Optola offer wide range of different dimensions LBO crystals.
  • Wide range of sizes are available upon request
  • Dimension tolerance: ±0.1mm
  • Clear aperture: central 90% of the diameter
  • Flatness: less than  λ/8 @ 633nm
  • Transmitting wavefront distortion: less than λ/8 @ 633nm
  • Chamfer: ≤0.2mm x 45°
  • Chip: ≤0.1mm
  • Scratch/Dig: 10/ 5
  • Parallelism: better than 20 arc seconds
  • Perpendicularity: ≤5 arc minutes
  • Angle tolerance: △θ≤0.25°, △φ≤0.25°
  • Damage threshold [GW/cm2]:

       >10 for 1064nm, TEM00, 10ns, 10HZ (polished only)
       >1    for 1064nm, TEM00, 10ns, 10HZ (AR-coated)
       >0.5 for 532nm,   TEM00, 10ns, 10HZ (AR-coated)

Transparency Range


SHG Phase Matchable Range

551-2600nm  (Type I)      790-2150nm (Type II)

Therm-optic Coefficient (/℃, λ in μm)


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)

NLO Coefficients

deff(I)=d32cosΦ                         (Type I  in XY plane)
deff(I)=d31cos2θ+d32sin2θ       (Type I  in XZ plane)
deff(II)=d31cosθ                         (Type II in YZ plane)
deff(II)=d31cos2θ+d32sin2θ      (Type II in XZ plane)

Non-vanished NLO susceptibilities

d31=1.05± 0.09 pm/V 
d32= -0.98± 0.09 pm/V
d33=0.05± 0.006 pm/V

Sellmeier  Equations
(λ in μm)  


Leave a Reply