Patent ID: 6914380
Filing Date: 2005-07-05
Classification: B82Y,H01J

Abstract:
1. A vacuum fluorescent display comprising: a cathode electrode for emitting electrons; a grid electrode for extracting the electrons from said cathode electrode; an anode electrode for accelerating the electrons extracted from said cathode electrode; at least one envelope which accommodates said cathode electrode, said grid electrode, and said anode electrode in a vacuum space and has a display portion having light transmission properties, a phosphor layer formed on an inner surface of the display portion of said envelope and adapted to emit light upon bombardment of the electrons accelerated by said anode electrode; and a cap made of an X-ray shielding material and supported outside said envelope so as to surround the display portion of said envelope through a gap, said cap having a light exit surface from which the light emitted from said phosphor layer emerges through the display portion of said envelope, wherein said cap surrounds said envelope entirely; wherein said envelope has a stem in which a plurality of lead pins to be connected to said electrodes are buried and which has an outer diameter slightly larger than that of said envelope, and a portion between a tip of an opening of said cap and said envelope is sealed by the stem to form the gap, wherein said stem is made of an insulating elastic material; a cooling liquid sealed in the gap and a liquid reservoir formed in the stem to communicate with the gap.