CASTECH Inc. researches, develops, produces, and sells crystal components, precision optical components, and laser devices in China and internationally. Its products include functional crystals such as laser, nonlinear optical, birefringent, magneto-optical, acousto-optic, and electro-optical crystals; precision optical components such as windows, mirrors, lenses, prisms, polarizing mirrors, waveplates, beam splitters, and diffraction gratings; and magneto-optical, acousto-optical, and electro-optical devices, drivers, optical switches, and fiber optic transmission devices. The company also manufactures and sells optoelectronic components and optical crystal materials, and engages in investment, information transmission, software and IT, and scientific research and technical services. Its products are mainly used in solid-state and fiber lasers, optical communications, AR, laser, radar, semiconductor equipment, optical detection equipment, industrial measurement, life sciences, precision instruments, and intelligent equipment. CASTECH Inc. was founded in 1988 and is based in Fuzhou, China.