▎ 摘　　要

NOVELTY - A carbon fiber for a field electron emitter has a coaxial stacking morphology of truncated conical tubular graphene layers (12). Each graphene layer includes a hexagonal carbon layer (10). It has large and small ring ends. The edges of the carbon layers are exposed on at least a portion of the large ring ends, and the exposed edges function as electron emission tips. USE - For field electron emitter (claimed). ADVANTAGE - The invention provides a carbon fiber for a field electron emitter in which a large number of edges of graphene layers can be exposed and a greater amount of emission current can be obtained. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for manufacturing a field electron emitter comprising dispersing the carbon fibers in a dispersion medium. The carbon fibers are deposited on an electrode by spraying, and dried to form a carbon fiber layer. DESCRIPTION OF DRAWING(S) - The figure is a schematic view showing a copy of a transmission electron micrograph of a carbon fiber having a herring-bone structure. Hexagonal carbon layer (10) Graphene layers (12)