Optical Materials
  Optical Glass
  Low Expansion Materials
  IR Materials
Micro-Optical Components
Fiber Optic Components
Light Sources & Photodiodes

Lithium Triborate (LiB3O5)

Lithium Triborate is a nonlinear optical crystal discovered and developed by Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science. It has a wide transparency range, high damage threshold, a relatively large effective SHG coefficient, and desirable chemical and mechanical properties. These properties make it suitable for frequency mixing and other nonlinear optical applications.


  • Wide transmission region from 160 nm to 2600 nm
  • Wide acceptance angle and small walk-off
  • Relatively Large effective second-harmonic-generation (SHG) coefficient
  • High damage threshold
  • High Optical homogeneity
  • Non-critical phase matching (NCPM) in a wide wavelength range


Figure 1: External transmittance curve of a 10mm lithium triborate sample

  Crystal Structure Orthorhombic
  lattice constant (Å) a = 8.4473, b = 7.3788, c = 5.1395
  Melting Point (°C) 834
  Optical Homogeneity (/cm) ≈10-6
  Mohs Hardness 6
  Density (g/cm^3) 2.47
  Absorption Coefficient (/cm) α<0.001  at 1064nm
  Coefficient of Thermal Expansion ( /K)
ax: 10.8X10-5
ay: -8.8X10-5
az: 3.4X10-5
  Transmission Range (nm) 160~2600
  Damage Threshold (GW/cm2)
18.9  at 1053nm (1.3ns)
  Refractive Indices nx = 1.5656, ny = 1.5905, nz=1.6055 at 1064nm
  nx = 1.5785, ny = 1.6065, nz=1.6212 at 532nm
  nx = 1.5973, ny = 1.6286, nz=1.6444 at 355nm
  Sellmeier Equations (λ in um)
nx2 = 2.454140+0.011249/(λ2-0.011350)-0.014591×λ2-6.60×10-5×λ4
ny2 = 2.539070+0.012711/(λ2-0.012523)-0.018540×λ2-2.0×10-4×λ4
nz2 = 2.586179+0.013099/(λ2-0.011893)-0.017968×λ2-2.26×10-4×λ4
  Nonlinear Optical Coefficients (pm/V)
d31 = 1.05
 d32 = -0.98
  d33 = 0.05
  Table 1: LiB3O5 Properties

Copyright © 2016 Precision Micro-Optics Inc. All Rights Reserved.