A titanium-sapphire laser (also known as a Ti:sapphire laser, Ti:Al2O3 laser or Ti:sapph) is a tunable laser which emits red and near-infrared light in the range from 650 to 1100 nanometers. This type of laser is mainly used in scientific research because of its tunability and its ability to generate ultrashort pulses, thanks to its broad light emission spectrum. Lasers based on Ti:sapphire were first constructed and invented in June 1982 by Peter Moulton at the MIT Lincoln Laboratory.
Titanium-sapphire refers to the lasing medium, a crystal of sapphire (Al2O3) that is doped with Ti3+ ions. A Ti:sapphire laser is usually pumped with another laser with a wavelength of 514 to 532 nm, for which argon-ion lasers (514.5 nm) and frequency-doubled Nd:YAG, Nd:YLF, and Nd:YVO lasers (527–532 nm) are used. They are capable of laser operation from 670 nm to 1,100 nm wavelength. Ti:sapphire lasers operate most efficiently at wavelengths near 800 nm.