NON-ELECTRIC LIGHT SOURCES USING LUMINESCENCE; LIGHT SOURCES USING ELECTROCHEMILUMINESCENCE; LIGHT SOURCES USING CHARGES OF COMBUSTIBLE MATERIAL; LIGHT SOURCES USING SEMICONDUCTOR DEVICES AS LIGHT-GENERATING ELEMENTS; LIGHT SOURCES NOT OTHERWISE PROVIDED FOR

Description

Subclass F21K encompasses non-electric and alternative light sources including luminescent materials, electrochemiluminescent systems, combustion-based lighting, and semiconductor light-emitting devices. This classification covers light generation technologies that do not rely on traditional electric filament or gas discharge methods, such as phosphorescent paints, chemiluminescent reactions, LED and laser diodes, and flame-based lighting systems. It serves as a residual category for innovative light sources that do not fit established classifications within the broader F21 lighting section. Adjacent classes in F21 cover electric incandescent lamps (F21B), fluorescent and discharge lamps (F21C/D), and electric lamp details and accessories (F21V/S).

Filing statistics

CPC subclass F21K recorded 35,490 patent applications worldwide between 2013 and 2023. Annual filings declined from 5,122 in 2013 to 1,262 in 2023 (-75%). The most active applicants in class F21 are VALEO VISION (2,820 applications), SIGNIFY HOLDING (2,374 applications) and KOITO MANUFACTURING COMPANY (1,890 applications).

Source: EPO PATSTAT, worldwide filings