Wide illumination range fluorescent lamp

摘要

A wide illumination range fluorescent lamp is described. The lamp utilizes three discrete sets of electrodes positioned to generate electric field to produce light energy within three distinct ranges of light intensity. The electrodes include primary electrodes for creating a plasma arc discharge through the lamp, a secondary electrode along the interior walls of the lamp to produce electric fields along the discharge channel and a transparent cover electrode coupled with a base electrode to produce an electric field between the cover and the base of the lamp. Each of the three sets of electrodes operates within a different brightness range such that together the three electrodes provide illumination across a range from 0.1 foot-lamberts to 20,000 foot- lamberts. In an alternative embodiment of the invention, the primary electrodes are housed within secondary housings bonded to the base of the lamps such that the electrodes are concealed beneath the base of the lamp. In this embodiment, light is emitted from substantially the entire upper surface of the lamp.