LBO  (三硼酸锂晶体)

LBO  (三硼酸锂晶体)


LBO(三硼酸锂)晶体是一种优良的倍频晶体,是目前应用比较广泛的一种倍频器件,其晶体内部光学均匀性良好、透过波段比较宽,具有较高的匹配效率和激光损伤阈值.。

优点  

可透光波段范围宽 (160-2600nm)
光学均匀性好,内部包络少
倍频转换效率较高(相当于KDP晶体的3倍) 
高损伤域值(1.3ns脉宽的1053nm激光可达10GW/cm2)
接收角度宽,离散角度小Ⅰ, Ⅱ类非临界相位匹配(NCPM)的波段范围宽
光谱非临界相位匹配(NCPM)接近1300nm

 

 

基本特性

Items Specifications
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°C
Mohs Hardness     6
Density  2.47 g/cm3
Thermal Conductivity    3.5W/m/K
Thermal Expansion Coefficient αx=10.8x10-5/K, aαy= -8.8x10-5/K, aαz=3.4x10-5/K
Transparency Range 160-2600nm
SHG Phase Matchable Range 551 ~ 2600nm  (Type I)      790-2150nm (Type II)
Therm-optic Coefficient
(°C, λ in μm)
dnx/dT=-9.3X10-6
dny/dT=-13.6X10-6
dnz/dT=(-6.3-2.1λ)X10-6
Absorption  Coefficient <0.1%/cm at 1064nm    
<0.3%/cm at 532nm
Angle Acceptance 6.54mrad-cm    (φ, Type I,1064 SHG)
15.27mrad-cm    (θ, Type II,1064 SHG)
Temperature Acceptance 4.7°C-cm   (Type I, 1064 SHG)
7.5°C-cm   (Type II,1064 SHG)
Spectral Acceptance 1.0nm-cm (Type I, 1064 SHG)
1.3nm-cm (Type II,1064 SHG)
Walk-off Angle  0.60°  (Type I  1064 SHG)
0.12°  (Type II  1064 SHG)
NLO Coefficient deff(I)=d32cosf              (Type I  in XY plane)
deff(I)=d31cos2q+d32sin2q    (Type I  in XZ plane)
deff(II)=d31cosq              (Type II in YZ plane)
deff(II)=d31cos2q+d32sin2q    (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
Sellmeier  Equations
(λ in μm)      
n2x =2.454140+0.011249/(λ2 -0.011350)-0.014591λ2 -6.60´10-5 λ2 ( l in mm, T=20 oC)
n2y =2.539070+0.012711/(λ2 -0.012523)-0.018540λ2+2.00´10-4 λ2 ( l in mm, T=20 oC)
n2z =2.586179+0.013099/(λ2 -0.011893)-0.017968λ2-2.26´10-4 λ2 ( l in mm, T=20 oC)

损伤阈值比较

Comparison of Bulk Damage Threshold (@1053nm ,1.3ns) 
Crystal Energy Density (J/cm2 ) Power Density (GW/cm 2 ) Ratio
KTP  6.0  4.6  1.00 
KDP  10.9  8.4  1.83 
BBO  12.9  9.9  2.15 
LBO 24.6 18.9 4.1

加工能力

常规精度等级
尺寸公差 (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+0.2/-0.1mm) (L<2.5mm)
通光孔径 Central 90% of the diameter
面形 ≤Lambda/8 @ 632.8nm
波前畸变 ≤ Lambda/8 @ 632.8nm
倒边 ≤0.2mm@45°
崩边 ≤0.1mm
表面光洁度 S/D 10-5
平行度 ≤ 20 arc seconds
垂直度 ≤ 5 arc minutes
角度公差 qD≤0.25°, fD≤0.25°
损伤阈值[GW/cm]:  >10 for 1064nm, TEM00, 10ns, 10HZ (polished only)
>1 for 1064nm, TEM00, 10ns, 10HZ (AR-coated)
>0.5 for 532nm, TEM00, 10ns, 10HZ (AR-coated)
AR膜层 Dual Band AR-coating (DBAR) of LBO for SHG of 1064nm.
   - low reflectance (R<0.2% at 1064nm and R<0.5% at 532nm );
   - high damage threshold (>500MW/cm2 at both wavelengths);
   - long durability.
Broad Band AR-coating (BBAR) of LBO for SHG of tunable lasers.

可以根据客户的要求