DIFF Subgroup
G01L 23/06 Indicating or recording by optical means
Introduced: September 1968
Full Title
Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid > Indicating or recording by optical means
No child classifications to compare. This is a leaf node in both IPC and CPC.