BBO
BBO crystal is an efficient NLO crystal for the second, third and fourth harmonic generation of Nd:YAG lasers, and the best NLO crystal for the fifth harmonic generation at 213 nm. Conversion efficiencies of more than 70% for SHG, 60% for THG and 50% for 4HG, and 200 mW output at 213 nm (5HG) have been obtained, respectively. BBO crystal has the following.
Advantages of BBO Crystals
Broad phase-matching range from 409.6 nm to 3500 nm
Wide optical transmission from 190 nm to 3500 nm
Large effective second-harmonic-generation (SHG) coefficient
High damage threshold of 10 GW/cm2 for 100 ps pulse-width at 1064 nm
Wide temperature-bandwidth of about 55℃
Good mechinical and physical properties
Capabilities:
| Aperture: | 2x2 ~ 25x25mm |
| Lenght: | 0.01 - 25mm |
| Cutting Angle q and f: | Determined by different kinds of homonic generartion |
| Phase matching type: | Type I or Type II |
| End Configuration: | Plano/Plano or Brewst/Brewst or Specified |
Specifications:
| Angle tolerance: | Δθ< ± 0.5°; Δφ< ±0.5° |
| Dimensional Tolerance: | (W ± 0.1mm) x (H ± 0.1mm) x (L + 0.2mm/-0.1mm) |
| Flatness: | <λ/8 at 633nm |
| Surface Quality: | 10/5 S/D |
| Parallelism: | < 20 arc seconds |
| Perpendicularity: | < 5 arc minutes |
| Wavefront Distortion: | <λ/8 at 632.8nm |
| Clear Aperture: | Central 95% |
| Chamfer: | 0.15x45° |
| Coating: | * Protective coating is required to prevent polished surfaces from fogging. * Anti-reflective coating should be considered if low reflectivity is required. |
Properties:
| Crystal Structure | trigonal, space group R3c |
| Cell Parameters | a = b = 12.532Ä, c = 12.717Ä, Z = 6 |
| Melting Point | 1095 +/-5°C |
| Transition Temperature | 925 +/-5°C |
| Optical Homogeneity | Dn ≈10-6/cm |
| Mohs Hardness | 4.5 |
| Density | 3.85 g/cm3 |
| Absorption Coefficient | < 0.1%/cm (at 1064 nm) |
| Hygroscopic Susceptibility | low |
| Resistivity | > 1011 ohm-cm |
| Relative Dielectric Constant | eT11/e0: 6.7, eT33/e0: 8.1 Tan d, < 0.001 |
| Thermal Expansion Coefficients(in the range of 25℃- 900℃) | a, 4 x 10-6/K c, 36 x 10-6/K |
| Thermal Conductivity | ^c, 1.2 W/m/K; ||c, 1.6 W/m/K |
| Phase-matchable SHG range | 205nm-1750nm |
| NLO coefficients | d11 = 5.8 x d36(KDP) d11 = 0.05 x d11, d22< 0.05 x d11 |
| Electro-Optic Coefficients | g11 = 2.7 pm/V, g22, g31< 0.1 g11 |
| Half-Wave Voltage | 48 KV (at 1064 nm) |
| Damage Threshold at 1.064 mm at 0.532 mm |
5 GW/cm2 (10 ns); 10 GW/cm2 (1.3 ns)1 GW/cm2 (10 ns); 7 GW/cm2 (250 ps) |
| Transparency Range | 189 - 3500 nm |
| Refractive Indices at 1.0642 mm at 0.5321 mm at 0.2660 mm |
ne = 1.5425, no = 1.6551 ne = 1.5555, no = 1.6749 ne = 1.6146, no = 1.7571 |
| Therm-Optic Coefficients | dno/dT = - 9.3 x 10-6/℃ dne/dT = -16.6 x 10-6/℃ |
Sellmeier Equations:
no2(l) = 2.7359+0.01878/(l2-0.01822)-0.01354 l2
ne2(l) = 2.3753+0.01224/(l2-0.01667)-0.01516 l2
BBO optical properties:
Transparence range: 189-3500nm
Second harmonic generation (SHG) range: 410-2400nm
Type I phase matching plane: X-Z plane, f=0°
Type I phase matching plane: X-Z plane, f=30°
The crystals with different angle cut for various applications are listed as follows:
1) Harmonic generations of Nd:YAG lasers:
1064nm SHG --> 532nm: 4x4x7mm Type I , q=22.8°, f=0°;
1064nm THG --> 355nm: 4x4x7mm Type I, q=31.3°, f=0°; Type II q=38.6°, f=30°
1064nm 4HG --> 266nm: 4x4x7mm Type I, q=47.6°, f=0°;
1064nm 5HG --> 213nm: 4x4x7mm Type I, q=51.1°, f=0°;
2) OPO and OPA pumped by harmonics of Nd:YAG lasers
532nm Pump --> 680-2600nm: 8x6x12mm Type I, q=21°, f=0°;
355nm Pump --> 410-2600nm: 8x6x12mm Type I, q=30°, f=0°; Type II, q=37°, f=30°;
266nm Pump --> 295-2600nm: 8x6x12mm Type I, q=39°, f=0°;
3) Frequency doubling of dye lasers
670-530nm SHG --> 335-260nm: 8x4x7mm Type I, q=40°, f=0°;
600-440nm SHG --> 300-220nm: 8x4x7mm Type I, q=55°, f=0°;
444-410nm SHG --> 222-205nm: 8x4x7mm Type I, q=80°, f=0°;
4) Harmonic generations of Ti:Sapphire lasers
700-1000nm SHG --> 350-500nm: 5x5x0.2mm Type I, q=28°, f=0°;
700-1000nm THG --> 240-330nm: 5x5x0.2mm Type I, q=42°, f=0°;
700-1000nm FHG --> 210-240nm: 5x5x0.2mm Type I, q=66°, f=0°;
5) Frequency doubling and tripling of alexandrite lasers
720-800nm SHG --> 360-400nm: 6x4x7mm Type I, q=31°, f=0°;
720-800nm THG --> 240-265nm: 6x4x7mm Type I, q=48°, f=0°;
6) Intracavity SHG of Ar+ laser with brewster angle cut BBO
514nm SHG --> 257nm: 4x4x7mm Type I, q=51°, f=0°, B-cut;
488nm SHG --> 244nm: 4x4x7mm Type I, q=55°, f=0°, B-cut;
Mounting: In order to prevent crystals from damaging or to be easily operated, We provide three kinds of mount of holder to install different dimension crystals. Please contact our sales for more information.