Popular Design for Narrow Band Interference Filter - KTA Crystal – Dien

Potassium Titanyle Arsenate (KTiOAsO4), or KTA crystal, is an excellent nonlinear optical crystal for Optical Parametric Oscillation (OPO) application. It has better non-linear optical and electro-optical coefficients, significantly reduced absorption in the 2.0-5.0 µm region, broad angular and temperature bandwidth, low dielectric constants. And its low ionic conductivities  result in higher damage threshold compared with KTP .
KTA is often used as an OPO / OPA gain medium for emission in the 3µm range as well as an OPO crystal for eye-safe emission at high average power.
Feature:
Transparent between 0.5µm and 3.5µm
High non-linear optical efficiency
Large temperature acceptance
Lower birefringence than KTP resulting in a smaller walk-off
Excellent optical and non-linear optical homogeneity
High damage threshold of AR-coatings: >10J/cm² at 1064nm for 10ns pulses
AR-Coatings with low absorption at 3µm available
Qualified for space projects