Variable Intensity Control of Fluorescent Lamp
Original Publication Date: 1982-Aug-01
Included in the Prior Art Database: 2005-Feb-10
Fluorescent lamp 10 in the above circuit has its intensity controlled by regulating the AC current through the lamp. This current is controlled by varying the circuit operating frequency or by modulating transistor 12 on-time (duty cycle). The lamp 10 is AC controlled. In one direction, current through the lamp 10 is supplied by DC supply 13, and stabilized by the combination of inductor 11 and capacitor 14. In the other direction, current is supplied by capacitor 14. The 3.6 VAC source 15 supplies power to the lamp electrodes.