Fiber optic collimators come in all sizes commercially. Most of them are based on the successful GRIN lenses, which find their way into many passive and active components. However, GRIN lenses are not very suitable for visible wavelengths or large beam. Our high performance collimators employ high quality aspheric lenses and achromatic doublets to achieve low wave-front distortion, low divergence, and diffraction limited beam qality. Large-beam collimators are not only ideal for long-range target shooting but also good for pair coupling at long working distances. Some of our very large-beam (>14 mm) collimators have been used in free-space optics communications. Use these collimators with our standard laser-diode light source, pigtailed diode lasers, or receptacle laser diode modules.