LBO is one of the excellent non-linear crystals in the ultraviolet band. It has been successfully used in second and third harmonic generation of YLF, YAG, YAP lasers. LBO crystal has wide transmission band, good ultraviolet transmittance, slightly deliquescence, good physical and chemical properties, moderate non-linear optical coefficient, good optical uniformity, high damage threshold, large allowable angle and small walk-off angle. It has been widely used in high average power second harmonic, sum frequency, difference frequency, third harmonic, fourth harmonic and parametric oscillation field
LBO crystal — the most excellent nonlinear crystal for Noncritical Phase Matched laser frequency doubling
The greatest advantage of LBO is that temperature tuning can be used to achieve non-critical phase matching (NCPM). When the non-critical phase matching relationship is satisfied in the frequency doubling process, the walk-off angle between the fundamental frequency light and the second harmonic of frequency doubling is 0. At this time, the effective length of LBO crystal can theoretically reach infinity, which can compensate for its small non-linear coefficient. Because its damage threshold is very large, it means that high-power fundamental wave pumping can be realized. Therefore, the conversion efficiency of fundamental frequency light will be greatly improved by using the non-critical phase matching of LBO crystal for the extra-cavity frequency doubling of pulsed laser. The beam quality and stability of frequency light will be greatly improved.
Parameter
| Property | Value |
| Chemical formula | LiB3O5 |
| Crystal structure | Orthorhombic, Space group Pna21, Point group mm2 |
| Lattice Parameter | a=8.4473Å ,b=7.3788Å, c=5.1395Å, Z=2 |
| Mass density | 2.47 g/cm3 |
| Moh hardness | 6 |
| Melting point | About 834°C |
| Thermal conductivity | 3.5W/m/K |
| Birefringence | Negative biaxial crystal: 2Vz = 109.2˚ at λ = 0.5321μm |
| Crystal Dimension/mm | Length/mm | Application | Orientation Theta/Phi deg | ARCoatings S1/S2,nm/nm |
| 5 x 5 | 15 | THG@1064nm, Type II (e-oe) | 42.2/90 | 1064 + 532 / 355 |
| 15 | SHG@1064nm, Type I (e-oo) | 90/11.6 | 1064 + 532 / 1064 + 532 | |
| 6 x 6 | 0.9 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 |
| 1.9 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 2.8 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 3.7 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 10 x 10 | 0.9 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 |
| 1.9 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 2.8 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 3.7 | SHG@1030nm | 90/13.8 | 515 + 1030 / 515 + 1030 | |
| 3 x 3 | 10 | THG@1064nm, Type II (e-oe) | 42.2/90 | 1064 + 532 / 355 |
| 15 | SHG@1064nm, NCPM I Type | 90/0 | 1064 + 532 / 1064 + 532 | |
| 15 | THG@1064nm, Type II (e-oe) | 42.2/90 | 1064 + 532 / 355 | |
| 15 | SHG@1064nm, Type I (e-oo) | 90/11.6 | 1064 + 532 / 1064 + 532 | |
| 20 | SHG@1064nm, NCPM I Type | 90/0 | 1064 + 532 / 1064 + 532 |
| Property | Value |
| Orientation Tolerence | < 0.5° |
| Thickness/Diameter Tolerance | ±0.05 mm |
| Surface Flatness | <λ/8@632 nm |
| Wavefront Distortion | <λ/4@632 nm |
| Surface Quality | 10/5 |
| Parallel | 30〞 |
| Perpendicular | 15ˊ |
| Clear Aperture | >90% |
| Chamfer | <0.2×45° |
| Property | Value |
| Transparency Range | 169 – 2600 nm |
| Absorption Coefficient: | <0.1%/cm at 1064nm;<0.3%/cm at 532nm |
| Refractive Indices | |
| at 1.0642 mm | nx = 1.5656, ny = 1.5905, nz=1.6055 |
| at 0.5321 mm | nx = 1.5785, ny = 1.6065, nz=1.6212 |
| at 0.2660 mm | nx = 1.5973, ny = 1.6286, nz=1.6444 |
| Sellmeier Equations(λ in μm) | nx2=2.454140+0.011249/(λ2-0.011350)-0.014591λ2-6.60×10-5λ4 |
| ny2=2.539070+0.012711/(λ2-0.012523)-0.018540λ2+2.0×10-4λ4 | |
| nz2=2.586179+0.013099/(λ2-0.011893)-0.017968λ2-2.26×10-4λ4 |
| Property | Value |
| SHG Phase Matchable Range | 551 ~ 2600nm (Type I);790-2150nm (Type II) |
| 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 | |
| Therm-Optic Coefficients(°C,λ in μm) | dnx/dT=-9.3X10-6 |
| dny/dT=-13.6X10-6 | |
| dnz/dT=(-6.3-2.1λ)X10-6 | |
| Angle Acceptance | 6.54mrad-cm (Φ, Type I,1064 SHG)15.27mrad-cm (q, Type II,1064 SHG) |
| T [K] | αt×106[ K-1],||X | αt×106[K-1 ],||Y | αt×106[ K-1],||Z |
| 273 | 107.1 | -95.4 | 33.7 |
| 323 | 108.2 | -88 | 33.6 |
| 373 | 108.3 | -80.9 | 33.2 |
| 423 | 107.3 | -74.0 | 32.6 |
| 473 | 105.3 | -67.3 | 31.7 |
| 523 | 102.3 | -60.7 | 30.5 |
| 573 | 98.2 | -54.4 | 29.1 |
| 673 | 87.0 | -42.3 | 25.5 |
| 723 | 79.8 | -36.5 | 23.3 |
| 773 | 71.6 | -30.9 | 20.9 |
| 873 | 52.1 | -20.3 | 15.3 |
| 923 | 40.8 | -15.3 | 12.1 |
| 973 | 28.5 | -10.6 | 8.7 |
| 1023 | 15.1 | -5.9 | 5.0 |
| 1073 | 0.8 | 1.5 | 1.1 |
| λ[µm] | nX | nY | nZ |
| 0.2537 | 1.6335 | 1.6582 | 1.6792 |
| 0.2894 | 1.6209 | 1.6467 | 1.6681 |
| 0.2968 | 1.6182 | 1.6450 | 1.6674 |
| 0.3125 | 1.6097 | 1.6415 | 1.6588 |
| 0.3341 | 1.6043 | 1.6346 | 1.6509 |
| 0.3650 | 1.59523 | 1.62518 | 1.64025 |
| 0.4000 | 1.58995 | 1.61918 | |
| 0.4047 | 1.5907 | 1.6216 | 1.6353 |
| 0.4358 | 1.5859 | 1.6148 | 1.6297 |
| 0.4500 | 1.58449 | 1.61301 | 1.62793 |
| 0.4861 | 1.5817 | 1.6099 | 1.6248 |
| 0.5000 | 1.58059 | 1.60862 | 1.62348 |
| 0.5250 | 1.57906 | 1.60686 | |
| 0.5321 | 1.57868 | 1.60642 | 1.62122 |
| 0.5461 | 1.5780 | 1.6057 | 1.6206 |
| 0.5500 | 1.57772 | 1.60535 | 1.62014 |
| 0.5780 | 1.5765 | 1.6039 | 1.6187 |
| 0.5893 | 1.5760 | 1.6035 | 1.6183 |
| 0.6000 | 1.57541 | 1.60276 | 1.61753 |
| 0.6328 | 1.5742 | 1.6014 | 1.6163 |
| 0.6563 | 1.5734 | 1.6006 | 1.6154 |
| 0.7000 | 1.59893 | 1.61363 | |
| 0.8000 | 1.56959 | 1.59615 | 1.61078 |
| 0.9000 | 1.56764 | 1.59386 | 1.60843 |
| 1.0000 | 1.56586 | 1.59187 | 1.60637 |
| 1.0642 | 1.56487 | 1.59072 | 1.60515 |
| 1.1000 | 1.56432 | 1.59005 | 1.60449 |
| Interacting wavelengths[μm] | Φexp [deg] | θexp [deg] |
XY plane θ=90° SHG, o+o ⇒ e | ||
| 1.908⇒0.954 | 23.8 | |
| 1.5⇒0.75 | 7 | |
| 1.0796⇒0.5398 | 10.6/10.7 | |
| 1.0642⇒0.5321 | 11.3/11.4/11.6/11.8 | |
| 0.946⇒0.473 | 19.4/19.5 | |
| 0.930⇒0.465 | 21.3 | |
| 0.896⇒0.448 | 23.25 | |
| 0.88⇒0.44 | 24.53 | |
| 0.850⇒0.425 | 27 | |
| 0.84⇒0.42 | 27.92 | |
| 0.836⇒0.418 | 28.3 | |
| 0.80⇒0.40 | 31.70 | |
| 0.794⇒0.397 | 32.3 | |
| 0.786⇒0.393 | 33 | |
| 0.78⇒0.39 | 33.70 | |
| 0.7735⇒0.38675 | 34.4 | |
| 0.75⇒0.375 | 37.13/37 | |
| 0.746⇒0.373 | 37.5 | |
| 0.7094⇒0.3547 | 41.8/41.9/42/43.5 | |
| 0.63⇒0.315 | 55.6 | |
| 0.555⇒0.2775 | 86 | |
| 0.554⇒0.277 | 90 | |
| SFG, o+o ⇒ e | ||
| 1.3414+0.6707⇒0.44713 | 20 | |
| 1.0642+0.5321⇒0.35473 | 37/37.1/37.2 | |
| 1.053+0.5265⇒0.351 | 38.2 | |
| 1.0642+0.35473⇒0.26605 | 60.7/61 | |
| 0.86+0.43⇒0.2867 | 61 | |
| 1.3188+0.26605⇒0.22139 | 70.2 | |
| 0.21284+2.35524⇒0.1952 | 50.3 | |
| 0.21284+1.90007⇒0.1914 | 63.8 | |
| 0.21284+1.58910⇒0.18774 | 88 | |
YZ plane, Φ=90◦ SHG, o+e ⇒ o | ||
| 1.908⇒0.954 | 46.2 | |
| 1.5⇒0.75 | 14.7 | |
| 1.0796⇒0.5398 | 19.2 | |
| 1.0642⇒0.5321 | 19.9/20.5/20.6/21.0 | |
| SFG, o+e ⇒ o | ||
| 1.0641+0.53205⇒0.3547 | 42/42.7 | |
| 1.0642+0.5321⇒0.35473 | 42.2/42.5/43.2 | |
XZ plane, Φ=0◦, θ＜VZ SHG, e+o ⇒ e | ||
| 1.3414⇒0.6707 | 3.6/4.2/5.0 | |
| 1.3188⇒0.6594 | 5.2 | |
| 1.3⇒0.65 | 5.4 | |
XZ plane, Φ=0◦, θ＞VZ SHG, e+e ⇒ o | ||
| 1.3414⇒0.6707 | 86.1/86.3/86.6 | |
| 1.3188⇒0.6594 | 86.0 | |
| 1.3⇒0.65 | 86.1 | |
| 1.24⇒0.62 | 86 |
Interacting wavelengths[μm] | T[℃] |
along X axis SHG, typeⅠ | |
1.547⇒0.7735 | 117 |
1.46⇒0.73 | 50 |
1.252⇒0.626 | 3.5 |
1.25⇒0.625 | -2.9 |
1.215⇒0.6075 | 21 |
1.211⇒0.6055 | 20 |
1.206⇒0.603 | 24 |
1.2⇒0.6 | 24.3 |
1.15⇒0.575 | 61.1 |
1.135⇒0.5675 | 77.4 |
1.11⇒0.555 | 108.2 |
1.0796⇒0.5398 | 112 |
1.0642⇒0.5321 | 148/148.5/149/149.5/151 |
1.047⇒0.5235 | 166.5/167/172/175/176.5/180 |
1.025⇒0.5125 | 190.3 |
SFG, typeⅠ | |
1.908+1.0642⇒0.6832 | 81 |
1.444+1.08⇒0.6179 | 23 |
1.135+1.0642⇒0.5491 | 112 |
1.547+0.7735⇒0.5157 | 141 |
DFG, typeⅠ | |
0.532-0.8⇒1.588 | 135 |
along Z axis SHG, type II | |
1.342⇒0.671 | 35 |
1.3⇒0.65 | 46 |
| Interacting wavelengths[μm] | T[℃] | Δφint [deg] | Δθint [deg] | ΔT[℃] |
| along X axis | ||||
| SHG, type I | ||||
| 1.46⇒0.73 | 50 | 6 | ||
| 1.252⇒0.626 | 3.5 | 9 | ||
| 1.206⇒0.603 | 24 | 13 | ||
| 1.135⇒0.5675 | 77.4 | 4.7 | ||
| 1.0642⇒0.5321 | 148 | 3.54 | 2.57 | 3.9 |
| 148.5 | 2.7 | |||
| 149 | 2.3 | 1.9 | 4 | |
| 149.5 | 4.1 | |||
| 151 | 2.1 | 2.1 | 2.9 | |
| 1.047⇒0.5235 | 175 | 3.5 | ||
| SFG, type I | ||||
| 1.908+1.0642⇒0.6832 | 81 | 7.4 | ||
| 1.444+1.08⇒0.6179 | 23 | 4.2 | 3 | |
| 1.135+1.0642⇒0.5491 | 112 | 5 | ||
| DFG, type I | ||||
| 0.532-0.8⇒1.588 | 135 | 3.8 |
| Interacting wavelengths[μm] | Φpm[deg] | θpm[deg] | Δφint[deg] | Δθint[deg] | ΔT[℃] | Δν[cm-1] |
| XY plane, θ =90(T=293K) | ||||||
| SHG, o+o ⇒ e | ||||||
| 1.0796⇒0.5398 | 10.7 | 0.31 | ||||
| 1.0642⇒0.5321 | 10.8 | 0.27 | 2.63 | |||
| 11.4 | 0.24 | 1.79 | ||||
| 11.6 | 5.8 | |||||
| 0.34 | 2.64 | 6.7 | 8.8 | |||
| 0.886⇒0.443 | 24.1 | 7.8 | 15.9 | |||
| 0.870⇒0.435 | 25.4 | 0.12 | 141 | |||
| 0.78⇒0.39 | 33.7 | 0.08 | 194 | |||
| 0.7605⇒0.38025 | 35.9 | 15.3 | 10.5 | |||
| 0.715⇒0.3575 | 41 | 0.06 | ||||
| SFG, o+o ⇒ e | ||||||
| 1.0642+0.3547⇒0.2661 | 60.7 | 3.8 | ||||
| YZ plane, φ =90(T=293K) | ||||||
| SHG, o+e ⇒ o | ||||||
| 1.0642⇒0.5321 | 20.6 | 3.2 | 0.77 | |||
| 3 | 0.81 | 11.5 | ||||
| SFG, o+e ⇒ o | ||||||
| 1.0641+0.53205⇒0.3547 | 42 | 0.79 | 0.16 | 6 | ||
| 1.0642+0.5321⇒0.35473 | 42.2 | 0.18 | ||||
| 41 | 3.07 | 0.18 |
| Interacting wavelengths[μm] | Φpm[deg] | θpm[deg] | β[fs/mm] |
| XY plane, θ =90◦ | |||
| SHG, o+o ⇒ e | |||
| 1.2⇒0.6 | 2.36 | 18 | |
| 1.1⇒0.55 | 9.37 | 37 | |
| 1.0⇒0.5 | 15.74 | 59 | |
| 0.9⇒0.45 | 22.94 | 86 | |
| 0.8⇒0.4 | 31.69 | 123 | |
| 0.7⇒0.35 | 43.38 | 175 | |
| 0.6⇒0.3 | 62.63 | 257 | |
| YZ plane, φ =90◦ | |||
| SHG, o+e ⇒ o | |||
| 1.1⇒0.55 | 15.98 | 82 | |
| 1.0⇒0.5 | 28.96 | 106 | |
| 0.9⇒0.45 | 45.36 | 139 | |
| 0.8⇒0.4 | 76.88 | 186 |
| λ[µm] | τp [ns] | Ithr [GW/cm2] | Note |
| 0.2661 | 12 | >0.04 | |
| 0.308 | 17 | >0.05 | |
| 0.0003 | 47,000 | sharp focusing | |
| 0.3547 | 18 | >0.18 | 10Hz |
| 8 | >0.1 | ||
| 7 | >0.14 | ||
| 0.03 | >9.4 | 10Hz | |
| 0.015 | >2.8 | ||
| 0.018 | >5 | ||
| 0.025 | >6 | 10Hz | |
| 0.5145 | CW | >0.00003 | |
| 0.5235 | 0.055 | >1.1 | 500Hz |
| 0.5321 | CW | >0.0004 | |
| 60 | >0.07 | 900Hz | |
| 10 | >0.22 | ||
| 0.1 | >4.5 | 500Hz | |
| 0.035 | >3.1 | ||
| 0.015 | >4.4 | ||
| 0.592 | 0.0005 | >50 | 1kHz |
| 0.605 | 0.0002 | >25 | |
| 0.616 | 0.0004 | 31,000 | sharp focusing |
| 0.652 | 0.02 | >0.81 | |
| 0.7–0.9 | 10 | >0.03 | 10Hz |
| 0.71–0.87 | 25 | 1.1–1.4 | 25Hz |
| 0.72–0.85 | 0.001 | >8 | |
| 0.77–0.83 | 0.00005 | >22 | 80MHz |
| 1.0642 | CW | >0.001 | |
| 60 | >0.06 | 1333Hz | |
| 18 | >0.6 | 10Hz | |
| 9 | >0.9 | 10Hz | |
| 8 | >0.5 | ||
| 1.3 | 19 | ||
| 1.1 | 45 | bulk damage | |
| 0.1 | 25 | ||
| 0.035 | >4.8 | ||
| 0.025 | >3.3 | 10Hz | |
| 1.0796 | 5 | 20 | 1–25Hz |
| 0.04 | 30 |
for spectral range 0.4–1.0µm and temperature range 293–338K (λ in µm):
dnX/dT=-1.8×10-6K-1
dny/dT=-13.6×10-6K-1
dnz/dT=-(6.3+2.1λ)×10-6K-1
for spectral range 0.4–1.0 µm and temperature range 293–383K (λ in µm):
dnX/dT=-(3.76λ-2.3)×10-6K-1
dny/dT=-(19.40-6.01λ)×10-6K-1
dnz/dT=-(9.70-1.50λ)×10-6K-1
for λ =0.6328µm and temperature range 293–473K (λ in µm, T in K):
dnX/dT=[0.20342-1.9697×10-2 (T-273)-1.4415×10-5(T-273)2]×10-6K-1
dny/dT=-[10.748+7.1034×10-2 (T-273) +5.7387×10-5(T-273)2]×10-6K-1
dnz/dT=-[0.85998+1.5476×10-1 (T-273) -9.4675×10-4(T-273)2+2.2375×10-6(T-273)3]×10-6K-1
| Specific Heat Capacity cp at P =0.101325 MPa | |||
| T [K] | cp[J/kgK] | ||
| 298 | 1060 | ||
| Linear Absorption Coefficient α | |||
| λ[µm] | α [cm-1] | ||
| 0.35–0.36 | 0.0031 | ||
| 1.0642 | 0.00035 | ||
| Two-photon Absorption Coefficient β | |||
| λ[µm] | τp[ns] | β×1011[cm/W] | Note |
| 0.211 | 0.0009 | 103±36 | θ =90°, Φ=30° |
| 0.264 | 0.0008 | 15±5 | θ =90°, Φ=30° |
| Nonlinear Refractive Index γ | |||
| λ[µm] | γ×1015[cm2/W] | Note | |
0.78 | 0.26±0.03 | [100] direction | |
| 0.19±0.03 | [010] direction | ||
| 0.85 | 0 .19±0.04 | ||
 |  |
| LBO Transmission Spectrum | SHG tuning curves of LBO Nonlinear Crystal |
 | |
| OPO tuning curves of LBO (TypeI (ooe) in ‘XY’ plane) with different pump light, namely 530 nm, 355 nm and 266 nm | |
- Low sensitivity to moisture
- Dispertive angle is small
- High optical homogeneity
- The range of tunable wavelengths is large
- The region of transparency is wide
- Damage threshold is high
- Wide acceptance angle
Material Processing
Optical Communication
Holography
Medical Applications
- OPA(Optical parametric amplifiers) and OPO(oscillators)
- SHG(Frequency harmonic doubling) and THG(Tripling harmonic doubling)
- Diode laser pumped Nd: YLF laser and Nd:YAG laser. Alexandrite, Ti:Sapphire, Dye Lasers, Ultrashort Pulse Lasers
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