Electroluminescent display and circuit protective device and method of

Abstract

An electroluminescent display device includes at least two conductive leads spaced from each other with a light-emitting element electrically coupled between such leads. A transparent, insulating base is formed about and between the leads. The base encapsulates both the leads and the light-emitting element. At least one lateral portion of each lead extends beyond the base and substantially conforms to the configuration of the base. In conforming such lateral portions, they are preferably wrapped around the base and fixed to it. These lateral portions are arranged so that light from the light-emitting element may pass axially through the base and out of its ends. In addition, light may pass laterally out of the base. The device may also be used for circuit protection purposes. To so use the device, a protective element is electrically coupled between the leads so that upon the occurrence of an overload condition in an external circuit coupled to the lateral portions, the protective element decouples the leads. Such decoupling results in the energization and illumination of the light-emitting element. The illumination indicates that an overload condition has occurred in the external circuit. The device may also be used simply for protection purposes. In this case a light-emitting element is not used. The device readily lends itself to fabrication in a lead-frame environment involving various metal forming steps, such as stamping, cutting, shaping, bending, and the like. These steps are used to form the leads and the lateral portions from a sheet of conductive material.