无汞平面光源亮度与发光效率的优化

Optimization of Luminance and Luminous Efficiency of Mercury-Free Flat Fluorescent Lamps

为了提高无汞平面光源的发光效率和避免放电收缩,本文设计并制作了一种新型的具有弧形电极结构的12寸无汞平面光源,基于该新型结构光源,对不同气压下Ne+Xe(10%),Ne+Xe(15%),Ne+Xe(30%)三种混合气体的光电特性以及驱动脉冲波形的上升沿对亮度及系统发光效率的影响进行了研究与分析。实验结果表明,平面光源的亮度随着气压的升高以及Xe含量的增加而升高,在60 kPa时采用Ne+Xe(30%)气体,其平均亮度可达7500 cd/m2;在气压低于60 kPa时,发光效率随气压的升高而急剧上升,随着气压的进一步升高以及Xe含量的增加,发光效率上升趋势逐渐变缓,甚至呈下降的趋势,在50 kPa时采用Ne+Xe(30%)系统最高发光效率可达23.7 lm/W;另外,通过优化驱动波形的上升沿,可以进一步提高平面光源的亮度及光效(约10%)。

A novel type of mercury-free flat fluorescent lamp（FFL）,12 inch in diameter,was designed and fabricated.The impacts of various factors,such as the pressure,Xe concentrations in three different gas mixtures of Ne and Xe：Ne＋Xe（10%）,Ne＋Xe（15%）,and Ne＋Xe（30%）,and the rising time of the driving waveform on the luminance and luminous efficiency were studied.The results show that the Xe concentration and pressure strongly affect the luminance and luminous efficiency.For instance,in the case of Ne＋Xe（30%） at 60 kPa,the averaged luminance was found to be 7500 cd/m2.In the range below 60 kPa,as the pressure rises up,its luminous efficiency rapidly increases,then,increases fairly slowly,peaking at 50 kPa with a maximum efficiency of 23.7 lm/W,and finally decreases with the increase of the Xe content.Interesting finding is that a steep rising edge within 400 ns increases the efficiency of the FFL by 10%.