Light bulb apparatus having a twisted LED filament for improved luminous efficiency and light distribution

Abstract

A light bulb apparatus includes a bulb shell, a flexible filament, a driver circuit and a bulb cap. The bulb shell has a top area and a lateral area. The flexible filament has a top portion and a lateral portion. The flexible filament is twisted as a spiral shape. More than 50% of a first light emitted from the lateral portion passes through the lateral area. More than 50% of a second light emitted from the top portion passes through the top area of the bulb shell. The driver circuit converts an external power source to a driving current supplied to the flexible filament. The bulb cap encloses the driver circuit for connecting to the external power source. The top area of the bulb shell and the bulb cap are located at two opposite sides of the lateral area of the bulb shell.

Dependencies are inferred from the claim text.