• All sections
• F - Mechanical engineering; lighting; heating; weapons; blasting
• F21K - 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
• F21K 9/233 - Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps

Patent holdings for IPC class F21K 9/233

Total number of patents in this class: 189

10-year publication summary

Principal owners for this class