Citation: |
Liping Wang, Jun Zou, Bobo Yang, Wenbo Li, Yang Li, Mingming Shi, Wei Zhu, Canyun Zhang, Fengchao Wang, Yujie Lin. Optical and electrical properties of a spiral LED filament[J]. Journal of Semiconductors, 2018, 39(2): 024003. doi: 10.1088/1674-4926/39/2/024003
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L P Wang, J Zou, B B Yang, W B Li, Y Li, M M Shi, W Zhu, C Y Zhang, F C Wang, Y J Lin. Optical and electrical properties of a spiral LED filament[J]. J. Semicond., 2018, 39(2): 024003. doi: 10.1088/1674-4926/39/2/024003.
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Optical and electrical properties of a spiral LED filament
DOI: 10.1088/1674-4926/39/2/024003
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Abstract
This paper introduces a new type of spiral white light-emitting diodes (WLED) filament with high luminous efficiency and uniform optical performance. The optical and thermal properties of the flexible filament were investigated at different stretching heights, namely 0, 1, 2, and 3 cm. The results indicated that the filament showed the best optical characteristics at the stretching height of 2 cm, because of good heat dissipation. In addition, the radiation temperature of the filament was inversely proportional to the output luminous flux. The reliability of the filament at a stretching height of 2 cm was also evaluated after 1000 h of use. The result demonstrated that the luminous flux decay of the bulb was only 0.85%. The flexible spiral WLED filament exhibiting high luminous flux and good reliability could be adapted to promote industrial development in the near future. -
References
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