Energy-Efficient, High-Color-Rendering LED Lamps Using Oxyfluoride and Fluoride Phosphors

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• 作者：Anant A. Setlur ; Emil V. Radkov ; Claire S. Henderson ; Jae-Hyuk Her ; Alok M. Srivastava ; Nagaveni Karkada ; M. Satya Kishore ; N. Prasanth Kumar ; Danny Aesram ; Anirudha Deshpande ; Boris Kolodin ; Ljudmil
• 刊名：Chemistry of Materials
• 出版年：2010
• 出版时间：July 13, 2010
• 年：2010
• 卷：22
• 期：13
• 页码：4076-4082
• 全文大小：873K
• 年卷期：v.22,no.13(July 13, 2010)
• ISSN：1520-5002

文摘

LED lamps using phosphor downconversion can be designed to replace incandescent or halogen sources with a “warm-white” correlated color temperature (CCT) of 2700−3200 K and a color rendering index (CRI) greater than 90. However, these lamps have efficacies of 70% of standard “cool-white” LED packages (CCT = 4500−6000 K; CRI = 75−80). In this report, we describe structural and luminescence properties of fluoride and oxyfluoride phosphors, specifically a (Sr,Ca)₃(Al,Si)O₄(F,O):Ce³⁺ yellow-green phosphor and a K₂TiF₆:Mn⁴⁺ red phosphor, that can reduce this gap and therefore meet the spectral and efficiency requirements for high-efficacy LED lighting. LED lamps with a warm-white color temperature (3088 K), high CRI (90), and an efficacy of 82 lm/W are demonstrated using these phosphors. This efficacy is 85% of comparable cool-white lamps using typical Y₃Al₅O₁₂:Ce³⁺-based phosphors, significantly reducing the efficacy gap between warm-white and cool-white LED lamps that use phosphor downconversion.