Development of lighting source with CCFL in T8-tube

In this research, two 13 W, 117 cm long CCFL are installed into a conventional T8 transparent tube with 119.8 cm in length. For retaining the original 38 W lighting capability, a well-performed reflection plate was installed at the center to project the emitting light of CCFL in the same direction to promote the lighting efficiency. The space between reflection plate and light tube is used to accommodate the CCFL driver circuit, thus inspiring the incentives of users to replace the conventional fluorescent lamp with CCFL. By utilizing burst mode dimming technique to regulate light output, the CCFL output voltage was intermittently outputted and the required dimming functions can be achieved. This research fully utilized the inductance of conventional magnetic ballast to accomplish power factor corrector by including appropriate capacitor. Accordingly, the input characteristics can be improved and high power factor performance can be achieved as well.