Abstract: A field-emission type switching device includes a substrate formed with a recess having a straight edge and serrated edge opposite to the straight edge. A gate electrode is formed at the bottom of the recess. An emitter electrode is provided over the substrate and formed with a serrated edge which is slightly off alignment with the serrate edge of the recess so as to provide an emitter overhanging portion overhanging the recess. Similarly, a collector electrode is provided over the substrate and formed with a straight edge which is slightly off alignment with the straight edge of the recess so as to provide a collector overhanging portion overhanging the recess. The emitter and collector electrodes are disposed in one plane and the gate electrode is disposed in another plane below the one plane.

Abstract: A double-ended arc discharge lamp includes a sealed, light-transmissive outer jacket, a light-transmissive shroud mounted within the outer jacket and directly supported by the outer jacket, and an arc discharge tube mounted within the shroud. The arc tube is typically a metal halide arc discharge tube. In a preferred embodiment, the shroud includes an outwardly flared portion at each end. The outwardly flared portions space the shroud from the outer jacket and support the shroud within the outer jacket. The outwardly flared portions of the shroud can be affixed to the outer jacket by fusing. The outer jacket can be provided with inwardly extending dimples for locating the shroud with respect to the outer jacket. In another embodiment, the outer jacket includes reduced diameter portions near each end which are attached to the shroud.

Abstract: A compact low pressure mercury vapor discharge lamp which utilizes an amalgam for reducing the vapor pressure of mercury by absorption. The lamp has a tubulation positioned at a location spaced from the lamp electrodes which is in communication with an arc sustaining gas and includes a container for retention of liquified amalgam within the tubulation. The mercury vapor from the electrical charge sustaining gas is in communication with the amalgam for absorption.