Sir John Herschel made the first observation of fluorescence from quinine
sulfate in 1845.
The term Fluorescence was coined by Sir George Stokes in 1852.
He observed a
blue hue from a solution of quinine sulfate.
Stokes
used sunlight to illuminate the quinine and observed the emission through a
stained glass filter
He showed that
the fluorescence emission occurred at a higher wavelength (lower energy)
than the excitation light. This
displacement is now called the Stokes
Shift
Edmund
Bequerel (1880)
Showed that
certain metal ion complexes emit radiation with a very long decay time.