KTP is an outstanding crystal for many applications in nonlinear optics and electro-optics, KTP is a colorless orthorhombic biaxial nonlinear crystal, the transparency range is from 0.35mm to 4.5mm.

Its large optical nonlinearity, high optical damage threshold, wide acceptable angle, low insertion loss and thermal stable phase-matching properties make KTP particularly suitable for frequency doubling of infrared lasers operating near 1mm(e.g.Nd:Laser) and for OPOs.

Its large linear electric-optic efficient and low dielectric constants make it attractive for electro-optic applications, such as modulators and Q-switchs.

KTP is also an excellent crystal used for OPO/OPA application. KTP crystal with X-cut configuration is mostly employed for non-critical phase matching (NCPM) OPO.

KTP is the mostly commonly used material for frequency doubling of Nd:YAG laser and other Nd-doped lasers.

The following parameters are typically required to specify when ordering:

► Sizes                               Width x Height x Length (mm)

► Phase matching angle     q and f

► Coating on S1&S2          Protective coating or reflectivity @ wavelength

KTP typical orientations:

► q=90°, f=23.5°,  For SHG@1064nm Type II phase matching.

► q=90°, f=74°~0°, For SHG Type II phase matching, fundamental wavelength range: 0.994—1.079mm.

► q=90°~54°, f=0°, For SHG type II phase matching, fundamental wavlength range: 1.079—2.0mm

► q=90°, f=0°(X-cut), or q=0°, f=0°(Z-cut), for NCPM application.

► q=0°, f=0°(Z-cut), gold coated on X-faces, for Q-switch application.

Phase matching angle: q and f

q and f are depended on different applications of frequency conversion.

The familiar phase matching angles are listed below:

SHG@1064nm Type II          q=90°, f=23.5°

SHG@1053nm Type II          q=90°, f=32.9°

SHG@1047nm Type II          q=90°, f=37.1°

SHG@1550nm Type II          q=53.7°, f=0°

NCPM                  q=90°, f=0°

Type I phase matching processes are prohibited because of its very low conversion efficiency.

If you’re not sure to calculate the phase matching angles, please contact us for assistance.