Description
It belongs to negative uniaxial crystal, no>ne, and refractivity ndex can be calculated with Sellmeier Equations (λ in μm):
no2 = 2.7359 + 0.01878 / (λ2 – 0.01822) – 0.01354 λ2
ne2 = 2.3753 + 0.01224 / (λ2 – 0.01667) – 0.01516 λ2
Below is the equation of two types effective frequency doubling coefficient of BBO crystal:
Type I: deff = d31 sinθ + (d11 cos3Φ – d22 sin3Φ) cosθ
Type II: deff= (d11 sin3Φ + d22 cos3Φ) cos2θ
Chemical and Structural Properties
| Crystal Structure | Trigonal, Space group R3c, |
| Lattice Parameter | a = b = 12.532 Å, c = 12.717 Å, Z = 6 |
| Melting Point | 1095 ±5℃ |
| Mohs Hardness | 4.4~5.0 Mohs |
| Density | 3.85 g/cm3 |
| Thermal Conductivity | 1.2 W/m/K(Perpendicular to c); 1.6 W/m/K(Parallel to c) |
| Thermal Expansion Coefficients | αa = 4 × 10-6 /K, αc = 36 × 10-6 /K |
Optical and Nonlinear Optical Properties
| Transparency Range | 189-3500 nm |
| Phase Matchable output wavelength | 189-1750 nm |
| Therm-optic Coefficient | dno/dT = -9.3 x 10-6°C-1
dne/dT = -16.6 x 10-6°C-1 |
| Absorption Coefficients | < 0.1% /cm @ 1064 nm, < 1%/cm @ 532 nm |
| Angle Acceptance | 0.8 mrad·cm (θ, Type Ⅰ, 1064 SHG)
1.27 mrad·cm (θ, Type Ⅱ, 1064 SHG) |
| Temperature Acceptance | 55 ℃·cm |
| Spectral Acceptance | 1.1 nm·cm |
| Walk-off Angle | 2.7 ° (Type Ⅰ, 1064 SHG)
3.2 ° (Type Ⅱ, 1064 SHG) |
| Non-vanished NLO Susceptibilities | d11 = 5.8 × d36 (KDP)
d31 = 0.05 × d11 d22<0.05 × d11 |
| Electro-optic Coefficients | γ22 = 2.7 pm/V |
| Half-wave Voltage | 7 KV（at 1064 nm, 3 × 3 × 20 mm3） |
Specifications
| Dimension Tolerance | (W ± 0.1 mm) × (H ± 0. 1 mm) × (L + 0.2/-0.1 mm; L≦20mm) |
| Clear Aperture | >90% |
| Surface Quality (Scratch/Dig) | 10/5 |
| Flatness | ≦λ/8 @633 nm |
| Transmitted Wavefront Distortion | ≦λ/8 @633 nm |
| Parallelism | 20’’ |
| Perpendicularity | ≦5’ |
| Angle Tolerance | ≦0.25° |
| Chamfer | ≦0.2 mm × 45° |
| Chip | ≦0.1 mm |
| Damage Threshold | ＞0.8GW/cm2 @1064 nm, 10 ns, 10 Hz AR-coating
＞0.3 GW/cm2 @532 nm, 10 ns, 10 Hz AR-coating |
* The above parameter data is just for reference and the crystal can be designed and produced based on your specific requirement and application.
*BBO crystals are prone to deliquescence, please store and use them in a dry environment and pay attention to protect the working surface for the texture is relatively soft.
