The function of the fiber collimator is to convert the light output from the fiber into collimated light (parallel light), or to couple external parallel light (approximately parallel) into the fiber for transmission, so that the maximum efficiency of light can be coupled into the desired device. 
The fiber collimator is packaged by a single fiber fiber pigtail and a lens precisely aligned. The lens is mainly composed of C-Lens (spherical) and G-Lens (planar). For the package tube, there are mainly two kinds of glass tubes and gold-plated tubes. According to different capillary outer diameters, there are a variety of outer diameter collimators. This product is widely used in optical devices or optical research and experimental fields.