DIFF Subgroup
G04B 19/32 by luminescent substances
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Indicating the time by visual means > Illumination of dials or hands > by luminescent substances
CPC:
Indicating the time by visual means ( by electric lamps G04C17/02; display arrangements in general G09F) > Illumination of dials or hands > by luminescent substances
No child classifications to compare. This is a leaf node in both IPC and CPC.