Castech, Inc. engages in the manufacture and sale of crystals for lasers and applications. The company products include high precision spherical, cylindrical & flat optics components for OEM customers from Industries of laser, telecom, biomedical instruments and analysis instruments. It also engages in the supply of nonlinear optical crystals, laser crystals and precision optics components. The company was founded in 1988 and is headquartered in Fuzhou, China.