They are widely used in telecommunications, sensing, spectroscopy, research and development, laser systems, medical devices, and industrial applications. Fiber optic collimators (also called fiber-optic collimators) are crucial optical components that convert the diverging output from an optical fiber into a collimated (parallel) beam, or conversely focus light from free space into a fiber. In essence, a simple collimation lens is all that is needed for this purpose. of FC or SMA type; they are not for use with bare fibers. Commercially offered collimators may offer several directional adjustments, e. It consists of an optical fiber and a lens, where the fiber guides the light and the lens collimates it.