MW Class Near Infrared Optics

Aiming laser weapons accurately is a difficult task that is made even more difficult if the laser windows and other components steer or distort the beam during thermal transients caused by the laser beam or other sources. Athermal components maintain the direction and wavefront quality of beams even in the presence of temperature gradients. Existing athermal materials do not have the high laser damage threshold and very low absorption of laser light required for future laser weapons. This project will demonstrate the creation of athermal windows and mirrors by combining existing near infrared high power laser component materials (such as fused silica) with other readily available materials (such as calcium fluoride or barium fluoride) that have negative dn/dT coefficients. The combiantion can be made athermal even though each component generally absorbs a different fraction of the laser beam and is heated to a different temperature.