CQD-LEDs with High Colour Rendering Index
Autor: | Doudou Zhang, Yuxian Yan, Luqiao Yin, Jianhua Zhang |
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Rok vydání: | 2020 |
Předmět: |
Materials science
business.industry Wide-bandgap semiconductor Phosphor 02 engineering and technology Color temperature 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences law.invention Full width at half maximum Semiconductor Quantum dot law Optoelectronics Chromaticity 0210 nano-technology business Light-emitting diode |
Zdroj: | 2020 17th China International Forum on Solid State Lighting & 2020 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS). |
Popis: | Quantum dots (QD), which is considered the ideal candidate of third generation semiconductor lighting, has the advantages of high quantum yield, adjustable emission wavelength and narrow full width at half maxima (FWHM), thus it is an ideal choice as the colour converting materials for LEDs. InGaN LEDs are the main choice of solid-state lighting, which is always applied with Ce-doped yttrium aluminum garnet (YAG: Ce3+) yellow phosphor to achieve white light. However, white light achieved by this method has a low colour rendering index (CRI), mainly because of the missing of red spectral components in YAG: Ce3+, thus the CRI is lower than 80 and the correlated colour temperature (CCT) is always above 6500K. In order to increase the CRI of white LEDs, in this paper, we fabricated yellow CQDs and applied it on blue LED chips, red QD films were also used to increase the CRI of our white LEDs. The result shows that the white LEDs with yellow CQDs and red QD films has a max CRI of 94.3 at a driving current of 70mA, the Commission International de L'Eclairage (CIE) chromaticity coordinates are (0.325, 0.3435), and the CCT is 5832K, which is white light with high CRI and can be used in indoor lighting. |
Databáze: | OpenAIRE |
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