Skip to Main Content
A progressive dimming circuit and method for 32 inch mercury-free flat fluorescent lamp (FFL) were presented based on a newly developed FFL, which showed a large operating margin, high luminance and high luminous efficacy in the case of unipolar driving. The proposed dimming circuit is simple in structure and the dimming method is easy to fulfill. The prototype of 32 inch FFL was built and verified. The results show that a progressive dimming can be implemented by pulse density modulation (PDM) method or frequency modulation method and the power consumption can be reduced since the light output of FFL can be controlled progressively. A dimming range about 100% to 6% can be achieved by using the proposed method.