Thorlabs' extensive line of optical lenses includes spherical, achromatic, aspheric, Powell, and cylindrical lenses, and are offered with or without antireflection coatings deposited on their surfaces. Substrate options include N-BK7, N-SF6, UV fused silica, calcium fluoride, magnesium fluoride, zinc selenide, germanium, and silicon. In addition, Thorlabs also offers axicons, air-spaced doublets, tunable lenses, and microlens arrays.