KTP is an abbreviation of potassium titanyl phosphate (KTiOPO4).
KTP crystals are widely used in nonlinear optics. The material carries high hyperpolarability (non-linear coefficient) to a wide transparency area and good thermal properties.
KTP crystals are used to convert a laser beam from one wavelength to another. An example is the frequency doubling or frequency trip of a Nd: YAG laser with Q switch: from 1064 nm (infrared) to 532 nm (green) or 355 nm (ultraviolet).
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