HOME Products Nonlinear Crystals KDP & KD*P Crystal

KDP & KD*P Crystal


Main Specification
Orientation accuracy of cut angle <30 arc min
Angle tolerance <10 arc min
Dimension tolerance +(0.05~-0.2) mm
Flatness <λ/4 @ 632.8 nm
Surface quality 20/10 Scratch/dig per MIL-O-13830A
Parallelism < 20 arc sec
Perpendicularity < 10 arc min
Wavefront distortion < λ/8 @ 633nm
Clear aperture > 90% central area
Working temperature 25°C
 
Other Properties
Crystal Structure Orthorhombic, Point group mm2, Space group Pna21
  KDP KD*P(DKDP)
Cell Parameters a=b=7.453; c=6.975 a=b=7.469; c=6.976
Chemical Formula KH2PO4 KD2PO4
Hardness 2.5 2.5
Density 2.338 g/cm3 2.355 g/cm3
Hygroscopic Susceptibility High High
Transparency Range 0.174 - 1.57 µm 0.2 - 2.1 µm
Refractive Indices no=1.4938, ne=1.4599 no=1.4948, ne=1.4554
at 1064nm at 1064nm
Sellmeier Equation no2 = 2.259276 + 0.01008956/(l2 - 0.012942625) + 13.005522l2/(l2 - 400) no2 = 1.9575544 + 0.2901391/(l2 - 0.0281399) - 0.02824391l2 +0.004977826l4
ne2 = 2.132668 + 0.008637494/(l2 - 0.012281043) + 3.2279924l2/(l2 - 400) ne2 = 1.5005779 + 0.6276034/(l2 - 0.0131558) - 0.01054063l2 +0.002243821l4
NLO coefficients(pm/V) d36 = 0.39 at 1.064 µm d36 = 0.37 at 1.064 µm
Electro-Optic Coefficients r41=8.8pm/V r41=8.8pm/V
r63=10.3pm/V r63=25pm/V
Longitudinal Half-Wave Voltage Vp=7.65KV(l=546nm) Vp=2.98KV(l=546nm)
Absorption/Absorptance 0.07/cm 0.006/cm
Optical Damage Threshold >5 GW/cm2 >3 GW/cm2
Extinction Ratio   30dB
   
Notice              Because polished surface could easily catch moistures,  KDP must be kept in dry condition (<50%) and sealed housing.
Engineers can select and design the best solution for you, if the main parameters of your laser are  provided, such as energy per pulse, pulse width and repetition rate for a pulsed laser, power for a cw laser, laser beam diameter, mode condition, divergence, wavelength tuning range, etc.