Process by which the resonance radiation emitted in a lamp is absorbed and re-emitted many
times in the plasma prior to striking the phosphor.
This process is called radiation trapping or imprisonment.
Note:
Radiation trapping lengthens the effective lifetime of emission as viewed from outside the lamp.
The control of this trapping is, therefore, an important design consideration for low-pressure lamps.
Source:
PAC, 2007, 79, 293
(Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006))
on page 410