The instantaneous light-intensity function of a fluorescent lamp

Abstract Using some simple physics and “system” considerations, the instantaneous light intensity function ψ ( t ) of a fluorescent lamp fed via a regular ballast from the 50–60 Hz line is argued to be ψ ( t ) = ψ min + b p ( t ) , where p ( t ) is the instantaneous power function of the lamp, and b is a constant, and experiment confirms this formula well. The main frequency of ψ ( t ) , the very significant singularity of its waveform, and the relative intensity of the ripple, i.e., the depth of the modulation, are the focus. The results are important for research into the vision problem that some humans (autistic, but others, too) experience regarding fluorescent light. The inertia of the processes in the lamp which are responsible for the light emission, provides some nonzero emission at the instants when p ( t ) has zeros. The smaller the volume of the tube and the mass of the gas are, the more weakly the inertia of the processes is expressed, and the relatively smaller is ψ min . However, it should be very difficult to theoretically obtain ψ ( t ) , in particular ψ min , from the very complicated physics of the low-pressure discharge in the tube. We conclude that ψ min has to be connected with the (also easily measured) lamp's inductance. The work should attract more attention of the physicists to the properties of the common fluorescent lamps.