LiNbO3 Crystal
LiNbO3 is widely used as electro-optic modulators and Qswitches for Nd:YAG, Nd:YLF and Ti:Sapphire lasers as well as modulators forfiber optics. The specifications in the following table list on typical LiNbO3
crystal used as Qswitch with transverse EO modulation. The light propagates in zaxis and electric field applies to xaxis. The electrooptic coefficients of LiNbO3 are: r33 = 32 pm/V, r31 = 10 pm/V, r22 = 6.8 pm/V at lowfrequency and r33 = 31 pm/V, r31= 8.6 pm/V, r22 = 3.4 pm/V at high electric frequency. The half–wave voltage: Vπ=λd/(2no3r22L), r c=(ne/no)3r33-r13.
LiNbO3 Q-Switch Specifications
Size
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9 X 9 X 25 mm3 or 4 X 4 X 15 mm3
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Other size is available upon request
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Tolerance of size
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Z-axis: ± 0.2 mm
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X-axis and Y-axis:±0.1 mm
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Chamfer
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less than 0.5 mm at 45°
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Accuracy of orientation
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Z-axis: <± 5’
X-axis and Y-axis: < ± 10’
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Parallelism
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< 20"
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Finish
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10/5 scratch/dig
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Flatness
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λ/8 at 633 nm
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AR-coating
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R < 0.2% @ 1064 nm
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Electrodes
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Gold/Chrome plated on X-faces
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Wavefront distortion
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<λ/4 @ 633 nm
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Extinction ratio
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> 400:1 @ 633 nm, φ6 mm beam
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LiNbO3 is also a good acoustooptic crystal and used for surface acoustic wave (SAW) wafer and A-O modulators. YS provide acoustic (SAW) grade LiNbO3 crystals in wafers, ascut boules, finished components and custom fabricated elements.
Typical SAW Properties
Cut Type
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SAW Velocity
Vs (m/s)
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Electromechanical Coupling Factor
k2s (%)
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Temperature Coefficient of Velocity
TCV (10-6/oC)
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Temperature Coefficient of Delay
TCD (10-6/oC)
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127.86o Y-X
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3970
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5.5
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-60
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78
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Y-X
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3485
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4.3
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-85
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95
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Typical Specifications
Type Specifications
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Boule
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Wafer
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Diameter
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Φ3"
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Φ4"
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Φ3"
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Φ4"
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Length or Thickness(mm)
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≤100
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≤50
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0.35-0.5
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Orientation
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127.86°Y, 64°Y, 135°Y, X, Y, Z, and other cut
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Ref. Flat Orientation
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X, Y
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Ref. Flat Length
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22±2mm
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32±2mm
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22±2mm
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32±2mm
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Front Side Polishing
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Mirror polished 5-15 ?
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Back Side Lapping
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0.3-1.0 mm
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Flatness (mm)
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≤ 15
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Bow (mm)
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≤ 25
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YS can offer other sizes and specifications of wafers upon request.