In this paper the effort of new driving schemes for cold cathode fluorescent lamp (CCFL) inverters in automotive LCDs is discussed. To achieve a very high dimming ratio a method to dim by varying the stimulation frequency of the inverter oscillator is developed. With the explained inverter principle an easy to optimize and high efficient system was found, that is suitable for automotive applications. The main advantages are the high efficiency, the high dimming ratio, the controlled oscillating frequency and excellent start up behavior. The start up behavior has to be pointed out, because this inverter principle guarantees a sure lighting of the lamp also under cold ambient areas with full dimming. With the described frequency dimming inverter a dimming ratio of 1:500 was reached.
Development of an inverter with frequency variation dimming
1999
6 Seiten, 6 Bilder, 5 Quellen
Aufsatz (Konferenz)
Englisch
Dimming glass, dimming device, dimming panel and vehicle
Europäisches Patentamt | 2021
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