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Features
Potassium Dihydrogen Phosphate (KDP) and Potassium Dideuterium Phosphate (KD*P ) are among the most widely-used commercial NLO materials. They are commonly used for doubling, tripling and quadrupling of Nd:YAG laser at the room temperature. In addition, they are also excellent electro-optic crystals with high electro-optic coefficients, widely used as electro-optical modulators, Q-switches, and Pockels Cells, etc.
Specifications
Capabilities:
Width x Length: 1x1 ~ 16x16mm
Lenght: 0.02 ~ 20mm

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: 20/10 Scracth/Dig
Parallelism: < 20 arc seconds
Perpendicularity: < 5 arc minutes
Wavefront Distortion: <λ/8 at 633nm
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:
  KDP KD*P
Chemical Formula KH2PO4 KD2PO4
Transparency Range 200-1500nm 200-1600nm
Nonlinear Coefficients d36=0.44pm/V d36=0.40pm/V
Refractive Index (at 1064nm) no=1.4938, ne=1.4599 No=1.4948, ne=1.4554
Electro-Optical Coefficients r41=8.8pm/V
r63=10.3pm/V
r41=8.8pm/V
r63=25pm/V
Longitudinal Half-Wave Voltage: Vp=7.65KV(l=546nm) Vp=2.98KV(l=546nm)
Absorptance: 0.07/cm 0.006/cm
Optical Damage Threshold: >5 GW/cm2 >3 GW/cm2
Extinction Ratio: 30dB 30dB


Sellmeier Equations of KDP:
no2 = 2.259276 + 0.01008956/(λ2 - 0.012942625) + 13.005522λ2/(λ2 - 400)
ne2 = 2.132668 + 0.008637494/(l2 - 0.012281043) + 3.2279924l2/(l2 - 400)

Sellmeier Equations of DKDP

no2 = 1.9575544 + 0.2901391/(l2 - 0.0281399) - 0.02824391l2 +0.004977826l4
ne2 = 1.5005779 + 0.6276034/(l2 - 0.0131558) - 0.01054063l2 +0.002243821l4