Crystals Land

  a-BBO

High temperature phase of a-BBO Crystal(BaB₂O₄₎ is one of the excellent birefringent crystals. It is characterized by large birefringent coefficient and wide transmission window ranged from 189nm to 3500nm. Due to its high chemical stability and medium hardness, a-BBO is fabricated easily into many kinds of optical components.

Physical and optical properties:

Transparency range	189-3500nm
Density	3.85g/cm3
Thermo-optic coefficients	dno / dT = -9.3 X 10-6 / ºC dne / dT = -16.6.3 X 10-6 / ºC
Optical homogeneity	Δn≈10-6/cm
Damage threshold	1 GW/cm2 at 1064nm500 MW/com2 at 532nm
Hygroscopic susceptibility	Low
Thermal expansion coefficients (25ºC--900ºC)	aa = 4 X 10-6 / K ac = 4 X 10-6 / K
Linear absorption coefficients	α<0.005cm-1 from 300nm to 2300nm
Refractive indices, birefringence (Δn=ne-no) and walk-off angle at 45º	ne=1.58462, no=1.65790 Δn=-0.073282; ρ=-4.9532º at 1064nm
	ne=1.60206, no=1.67755,Δn=-0.075491; ρ=-5.0407º at 532nm
	ne=1.67190, no=1.76171, Δn=-0.089805; ρ=-5.6926o at 266nm

Specifications:

Diameter	40~50mm
Length	25~35mm
S/D	20/10
Beam deviation	< 3 arc min
Optical axis orientation	+/-0.5º
Flatness	Better than l/8 @632.8nm
Transmission wave front distortion	<λ/4 @632.8nm
Coating	On request