Abstract: A cassette light retrofit adapted to be received in a housing portion of an existing lighting fixture from which the light tubes and door frame with diffuser have been removed comprises an open cassette enclosure having a door frame and diffuser closing the enclosure; a lightable tubing array in the cassette enclosure; a power converter in the enclosure connected to energize the lightable array; and, said cassette door frame being attachable to the fixture housing portion to replace said fixture door frame with the cassette enclosure being in said housing. The power converter uses 8 windings with isolation to improve the tracking efficiency of the sensing windings for accurate high frequency power application for the load. Also, an A.C. winding permits dimming of the lamp load by filling in chunks of voltage deleted by the dimmer.

Abstract: A miniature, light weight, high voltage, high frequency, high power output unique ballast and a unique sealable neon lamp in a light weight, light reflective box containing the ballast for use as one of a plurality of ceiling lamps. The ballast includes a transformer with a tuned secondary due to distributed capacitance, as a result of spaced apart first and second halves of the secondary winding, particularly wound in three separate sections of a bobbin fitted on the center leg of the transformer E--E core and tightly coupled to a center tapped primary winding on the center leg of the other section of the E-core. The section of the core are separated by a high dielectric spacer which also gaps the core when the sections are placed together. An asymetrical starting circuit prevents burnout of the alternate conducting FET switching device by insuring that only a selected one FET always starts first, and the unique bobbin and secondary winding prevents breakdown in the secondary high voltage winding.

Abstract: The invention comprises a fluid-tight light box containing a cold cathode light source activated by a high frequency ballast circuit small enough to be contained in the box.At least the box bottom interior is coated with a crinkle or matte finish to cause uniform brightness at or adjacent to a window in the upper side of the box. The ballast circuit is preferably also coated to avoid shadow effects.A milky element may comprise the window or be positioned adjacent thereto to comprise a light diffuser for a transparency adjacent thereto or the transparency may be coated on its reverse side with a diffuser coating.This display or portrait exhibitor may measure less than 2 inches thick and this is the reason the light reflective path and materials are so critical.