Abstract: An incandescent light bulb life extender circuit is designed to attach to the screw base of a conventional light bulb or incorporated in series with the AC powering the bulb. The circuit employs a bidirectional semiconductor switch that reduces the brightness of the bulb marginally while significantly extending the bulb's life. The values of the life extender are selected to operate with standard available light dimmers with no undesirable flicker or compromise of reasonable brightness control. A controller consists of the life extending circuit and a) an appropriate molded insulating housing, b) electrically conductive metallic discs for making electrical contacts to a light bulb base and corresponding socket and c) selected electronic components, connected to said discs, to facilitate the intended electrical performance.

Abstract: A metal halide high intensity discharge lamp having an arc tube assembly including a pair of discharge electrodes and a pair of starting electrodes. Each starting electrode is adjacent a respective discharge electrode. During starting, the lamp makes the glow discharge to arc discharge transition in a substantially shorter time than a lamp with a single starting electrode, and exhibits a substantially improved lumen maintenance.

Abstract: Ignition of high intensity discharge (HID) lamps can be enhanced by the application of ultrahigh frequency (UHF) electric fields at modest power levels. The implementation of UHF power assisted starting offers considerable advantage over known prior art lower frequency power starting methods. Solid state circuits and coupled means can be utilized as described therein.

Abstract: A triggerable ceramic gas tube voltage breakdown device, particularly adapted for use in an electrical circuit for controlling the light output of a photoflash lamp, includes means for reducing the attenuation of an electrical trigger pulse in the region of the electrode gap due to the ceramic spacer tube. The electric field intensity in the region of the electrode gap resulting from the trigger pulse may be enhanced by disposing annular conductive material in the region and by connecting that material to a source of the trigger pulses. Alternatively or in conjunction therewith, the configuration of the ceramic spacer tube may be altered by removing material from the ceramic spacer tube in the region of the electrode gap, thereby enhancing the electric field intensity in that region resulting from the trigger pulses.

Abstract: The invention relates to a high-pressure sodium lamp which is provided with a discharge tube having an external auxiliary electrode. The auxiliary electrode is switched off by a bimetallic switch in the operating condition of the lamp.According to the invention the lamp also comprises a glow starter which in the operating condition of the lamp is switched off by means of the same bimetallic switch. This apparatus achieves in a simple manner, a large available voltage for igniting the discharge tube with an operating condition of the lamp in which no disturbance is experienced from any of the ignition auxiliary means.