Abstract: A door frame hingeably mounted to a lensed fluorescent troffer lighting fixture and carrying a prismatic lens cover, the door frame also integrally provides a light trap function. Structural components of the door frame have fastening elements formed integrally therewith for attachment of said components together without the use of separate fastening elements. The door frame includes low profile latching structure which allows ready opening of the door frame for relamping or other maintenance functions, hinge elements acting not only to hold the door frame to the light fixture but also to hold the door frame in a fully open position. The door frame further acts to impart rigidity to the lighting fixture when in a closed position.

Abstract: An improved lensed fluorescent troffer lighting fixture intended for ceiling mounting and particularly for recessed mounting to a suspended ceiling grid within a shallow plenum, the embodiments of the fixture having dimensions, particularly depth-wise dimensions, which allow installation within the confines of reduced plenums while maintaining fixture quality and retaining desirable characteristics such as minimal lamp image. The present lensed troffers can be manufactured at a high assembly rate due to the ability to snap together on an assembly line the various components of the fixture without the use of separate fasteners. The lensed troffers of the invention are particularly configured for use with T8 fluorescent lamping and low profile electronic ballast.

Abstract: Extension brackets capable of being rapidly attached to standard lampholder brackets of conventional fluorescent lighting fixtures for retrofit of such fixtures to accommodate lamping, including metric lamping such as T5 lamping, of generally shorter lengths than conventional tubular fluorescent lamping. The extension brackets of the invention attach by interference fit to standard cutouts in standard lampholder brackets, which cutouts normally attach conventional "tombstone" T12 lampholders, the extension brackets further acting to mount conventional lampholders capable of mounting the metric lamping at locations disposed inwardly of the fixtures to accommodate the several conventional lengths of metric lamping or the like while locating the metric lamping on a plane no higher than that of the conventional lamping for which the lighting fixtures are originally configured.

Abstract: An improved light trap and louver mounting assembly particularly intended to be used as a component of a fluorescent troffer lighting fixture, the invention comprises a light trap structure formed with integral fastening elements which attach component parts of the light trap together, which attach the light trap to the louver and which releasably mount the light trap and louver mounting assembly to a housing assembly of the lighting fixture. The integral fastening elements of the invention act to provide the aforesaid functions without the use of separate fastening elements such as screws, hinges, latches and the like. The light trap and louver mounting assembly of the invention is structurally rigid and imparts desirable rigidity to the louver and to the lighting fixture.