Designed for use with single-mode polarization-maintaining fibers and fiber lasers, these collimators will generate a diffraction-limited beam with Gaussian profile at any distance along the path. Aperture sizes from 5 mm to 45 mm allow for beam sizes ranging from approximately 2 mm to 35 mm. Fine focus adjustment allows you to tune for your wavelength of use and obtain wavefront errors <1/10 wave. All collimators have receptacle for FC or FC/APC terminated fibers. Three wavelength regions cover the span from 370 nm to 1700 nm. There is no epoxy along the optical path, so these collimators can accept very large laser powers. All standard collimators are stocked for quick shipment. Custom collimators have been made for harsh environments such as vacuum, airborne, radiation fields, high magnetic fields and space. Pigtailed, fixed focus and various beam sizes are also available.