LBO crystal is an excellent 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.
Advantages:
1. Broad transparency range from 160nm to 2.6mm(SHG range from 0.55m to 2.6mm)
2. Relatively large effective SHG coefficient (about three times larger than that of KDP)
3. High damage threshold (18.9 GW/cm2 for a 1.3ns laser at 1.054mm)
4. Type I and type II non-critical phase-matching (NCPM) over a wide wavelength range
5. Wide acceptance angle and small walk-off
Applications:
6. More than 480 mW output at 395 nm is generated by frequency-doubling a 2W mode-locked Ti:Sapphire laser (<2ps, 82MHz). The wavelength range of 700~900 nm is covered by a 5x3x8 mm3 LBO crystal
7. The frequency-doubling of a Spectra-Physics TFR diode pumped Nd:YLF laser (>500mJ@1047 nm, < 7 ns, 0-10 KHz) reaches over 40% conversion efficiency in a 9 mm LBO.
8. The VUV output at 187.7 nm is obtained by sum-frequency generation
9. 2mJ/pulse diffraction-limited beam at 355 nm is obtained by intracavity tripling a Q-switched Nd:YAG laser
Chemical and Structural properties of LBO:
| Crystal Structure | Orthorhombic, Space group Pna21, Point group mm2 |
| Lattice Parameter | a=8.4473Å, b=7.3788Å , c=5.1395Å , Z=2 |
| Melting Point | About 834℃ |
| Mohs Hardness | 6 |
| Density | 2.47 g/cm3 |
| Thermal Conductivity | 3.5W/m/K |
| Thermal Expansion Coefficient | ax=10.8x10-5/K, ay= -8.8x10-5/K, az=3.4x10-5/K |
| Dimension tolerance | (W±0.1mm)x(H±0.1mm)x(L+0.5/-0.1mm) (L≥2.5mm) (W±0.1mm)x(H±0.1mm)x(L+0.1/-0.1mm) (L<2.5mm) |
| Clear aperture | Central 90% of the diameter |
| Flatness | Less than λ/8 @ 633nm |
| Transmitting wavefront distortion | Less than λ/8 @ 633nm |
| Chamfer | ≤0.2mmx45° |
| Chip | ≤0.1mm |
| Scratch/Dig code | Better than 10/ 5 to MIL-PRF-13830B |
| Parallelism | Better than 20 arc seconds |
| Perpendicularity | ≤5 arc minutes |
| Angle tolerance | Δθ≤0.25°, ΔΦ≤0.25° |
English
Deutsch
Русский