Abstract: A field emission cathode has particular use in a light source. The light source includes an evacuated container having walls, at least a portion of which consists of an outer glass layer which on at least a major part thereof is coated on the inside with a layer of phosphor forming a luminescent layer and a conductive layer forming an anode. The layer of phosphor is excited to luminescence by electron bombardment from a field emission cathode located in the interior of the container. A modulator electrode is arranged between the cathode and the anode for creating an electrical field necessary for the emission of electrons. The field emission cathode, includes a base body, and field emitting bodies extending from the base body. The base body includes a longitudinally extending core having a central axis. The field emitting bodies are elongate and are distributed along at least a part of the length of the core, extend radially outwards from the core, and have free ends provided with field emitting surfaces.

Abstract: A field emission cathode and methods for fabricating such a cathode from at least one body containing a first substance. The steps include a preparation of at least one irregularity in an emitting surface of the body, adding to the emitting surface of the body ions of a second substance with a low work function, and modifying the emitting surface by inducing field emission in applying a variable electric field to the body and increasing the field strength in steps.

Abstract: A field emission cathode (40) includes field emitting bodies (42) in the form of fibers, and a base body having a longitudinally extending core (41) formed by at least two wires (43) between which the fibers are secured. The fibers are distributed along at least a part of the length of the core (41) and extend radially outwards from the core. A light source (10) includes an evacuated container having walls at least a portion of which consists of an outer glass layer (23) on which at least a major part thereof is coated on the inside with a layer of phosphor (24) forming a luminescent layer, and a conductive layer forming an anode (25). The layer of phosphor (24) is excited to luminescence by electron bombardment from a field emission cathode (40) located in the interior of the container, and a modulator electrode or grid (30) is arranged between the cathode (40) and the anode (25) for creating an electric field for the emission of electrons.