Light bulb apparatus having a twisted LED filament for improved luminous efficiency and light distribution
US11231147B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 2021 |
| Grant date | Jan 25, 2022 |
| Priority date | — |
| Expiry date | Jan 15, 2041 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21Y2115/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.