Abstract: A thermionic fault current limiter utilizes either a vacuum or plasma environment for a plurality of spaced conduction electrodes. The electrode can be supported by insulative spacers with the electrode providing shadow shields for the supporting spacers. Electrode spacing, power density, temperature gradients, and control grids can be utilized for optimum operation and in establishing self-absorption of energy for a desired operating environment. Cesium desorption from the electrode surfaces can be utilized to enhance current termination.

Abstract: A display intensity control apparatus for controlling under dark ambient conditions the display intensity of an automobile display system comprises a plurality of display units (e.g., LED, FLT, Lamp) for providing displays effected by display elements of different types. Under dark ambient conditions, a pulse signal with a predetermined duty ratio is generated at a predetermined frequency and the display intensity of selected one of the display units is decreased in accordance with the duty ratio. Simultaneously, the duty ratio of the pulse signal is changed, and the display intensities of the other display units are decreased in accordance with the changed duty ratio.

Abstract: A non-light emitting insert for a fluorescent lighting fixture is used in place of a fluorescent lamp to complete a plural lamp ballast circuit so that the ballast is effective to illuminate properly any remaining fluorescent lamp coupled therein. The insert appears externally as a conventional fluorescent lamp including end electrical terminations that fit in the sockets of a fluorescent lighting fixture, and to an extent the insert duplicates the electrical effect of a lamp in a two lamp ballast circuit. Using the insert a reduction in the light output and a substantially corresponding reduction in consumed electrical power are achieved for a plural lamp fluorescent lighting fixture arrangement while at the same time the components of the ballast circuit are operated at reasonably normal electrical and temperature levels.

Abstract: A device for replacing a fluorescent lamp in a two lamp serially connected fluorescent fixture either of the type which includes a rapid-start type transformer for every two rapid-start fluorescent lamps or an instant start fixture for every two instant start lamps. By placing the device in the fixture in place of one of the two lamps the remaining lamp is energizable to provide illumination, whereas without the device the remaining lamp is inactive.