LBO crystal, Lithium Triborate, LiB3O5, is a nonlinear optical 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.

Unique features of LBO crystal:

  • Broad transparency range from 160nm to 2600nm; SHG range from 550nm to 2600nm.
  • High optical homogeneity ( δν =€10-6/cm) and free of inclusion.
  • Relatively large effective SHG coefficient. (about three times that of KDP)
  • Excellent for high power and stable second-harmonic generation. (minimal thermal lensing compared to KTP)
  • High damage threshold. (18.9 GW/cm2 for a 1.3ns laser at 1053nm;25 GW/cm2 for a 10 ns laser at 1064 nm)
  • 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.

LBO Crystal Applications:

  • Frequency doubling (SHG) and tripling (THG) of high power pulsed of Nd:YAG , Nd:YVO4, Nd:YLF, Ti:Sapphire and Dye lasers.
  • Optical parametric amplifiers (OPA) and oscillators (OPO) of both Type 1 and Type 2 phase-matching pumped by Excimer lasers and harmonics of Nd:YAG lasers.
  • Non-critical phase-matching (NCPM) for SHG 1064nm of laser.


Dimension tolerance (W +/- 0.1 mm) x (H +/- 0.1 mm) x (L + 0.2 mm/-0.1mm)
Flatness L/8 @633nm
Clear aperture > 90% central area
Surface quality 10/5 Scratch/Dig per MIL-O-13830A
Parallelism < 20 arcsec
Perpendicularity < 5 arcmin
Angle tolerance < +/-0.5°
AR coating

(SHG): R< 0.25% at 1064nm and R<0.4% at 532 nm

(THG): R< 0.6% at 1064nm & R<0.4% at 532 nm & R<0.5% at 355 nm

Coat damage threshold > 500MW/cm2