fibertip

Fibertip, or fiber tip, denotes the distal end of an optical fiber through which light is emitted or collected. The tip forms the optical interface between the fiber and its environment and is typically prepared to maximize coupling efficiency while protecting the fiber core from damage and contamination.

End faces are most often flat, produced by cleaving, but can be polished to spherical or aspheric shapes, or formed into micro-lenses to improve coupling. Angled or APC tips reduce back reflections in certain applications. Tips may be bare glass or coated with protective polymers or dielectric layers such as anti-reflection coatings.

Manufacturing methods include mechanical cleaving for straight end faces, polishing for smoothness, and microfabrication techniques to create lenses or tapering. Tapered or lensed tips can be produced by chemical etching, thermal drawing, or laser shaping to adjust beam diameter and numerical aperture.

Applications include telecommunications, fiber-optic sensing, medical and industrial imaging, endoscopy, and scanning near-field optical microscopy (NSOM). Tip performance is described by insertion loss, return loss, numerical aperture, and near-field aperture, as well as mechanical durability and environmental resistance.

Maintenance: Clean tips with lint-free wipes and appropriate solvents, avoid touching the endface, inspect with a fiber microscope, and protect with caps or connectors when not in use.