Enhancing color quality of WLEDs with dual-layer remote phosphor geometry

• Autorzy: That Phung Ton , Loan Nguyen Thi Phuong , Tho Le Van , Anh Nguyen Doan Quoc , Liao Hsing-Yuan , Luo Guo-Feng , Lee Hsiao-Yi

Identyfikatory

DOI

10.2478/msp-2020-0070

• Języki publikacji: EN

Abstrakty

EN

Usually, remote phosphor structures are beneficial in terms of flux but unfavorable in terms of color quality compared to conformal phosphor or in-cup phosphor packages. To eliminate this disadvantage, many studies have focused on increasing the chromatic quality of the remote phosphor configuration, which requires great efforts in improving two parameters of color: color rendering index (CRI) and color quality scale (CQS). CRI is known as the most useful quantitative method used to measure the ability of a light source to reproduce the colors of illuminated objects faithfully and naturally. Similarly, CQS is also a method of lighting quality determination and analysis, especially used as an alternative to the unsaturated CRI colors. In this paper, we proposed dual-layer remote phosphor structure as a novel method of CRI and CQS enhancement to improve WLEDs’ color quality. Five alike WLEDs but having different color temperatures in the range of 5600 K to 8500 K were applied in this study. The idea behind the study is to place a red phosphor layer Sr_wF_xB_yO_z:Eu²⁺,Sm²⁺ on the yellow phosphor layer YAG:Ce³⁺ and then determining an appropriate concentration of Sr_wF_xB_yO_z:Eu²⁺,Sm²⁺ added to achieve the highest color quality. The results point out that Sr_wF_xB_yO_z:Eu²⁺,Sm²⁺ brings great benefits to the improvement of CRI and CQS parameters. Specifically, the higher the Sr_wF_xB_yO_z:Eu²⁺,Sm²⁺ concentration results in the greater CRI and CQS, owning to the enriched red light components in the WLEDs. However, the flux has a tendency of dropping when Sr_wF_xB_yO_z:Eu²⁺,Sm²⁺ concentration rises excessively. This has been proved by using the Mie-scattering theory and the Lambert-Beer law. The results of this article are essential references for manufacturing WLEDs with higher chromatic quality.

Słowa kluczowe

EN

dual-layer remote phosphor geometry; WLEDs; Mie-scattering theory; color uniformity; luminous flux

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2020
• Tom: Vol. 38, No. 4
• Strony: 667--674
• Opis fizyczny: Bibliogr. 20 poz., rys.

Twórcy

autor

That Phung Ton

• Faculty of Electronics Technology, Industrial University of Ho Chi Minh City, Ho Chi Minh City, Vietnam

autor

Loan Nguyen Thi Phuong

• Faculty of Fundamental 2, Posts and Telecommunications Institute of Technology, Ho Chi Minh City, Vietnam

autor

Tho Le Van

• Institute of Tropical Biology, Vietnam Academy of Science and Technology, Ho Chi Minh City, Vietnam

autor

Anh Nguyen Doan Quoc

• Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam

autor

Liao Hsing-Yuan

• Department of Electrical Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan

autor

Luo Guo-Feng

• Department of Electrical Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan

autor

Lee Hsiao-Yi

• Department of Electrical Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan

Bibliografia

• [1] TANG Q., QIU K., LI J., ZHANG W., ZENG Y., J. Mater. Sci.: Mater. Electron., 28 (2017), 18686.
• [2] JIN L., DU X., LEI X. REN L., FENG Y., CHEN W., Appl. Phys. A, 114 (2014), 631.
• [3] DI X., HE X., JIANG J., LI P., XIANG W., LIANG X., SHEN T., J. Mater. Sci.: Mater. Electron., 28 (2017), 8611.
• [4] SON K.H., JEON Y.M., OH M.M., Hortic. Environ. Biotechnol., 57 (2016), 560.
• [5] CHIU Z.W., HSIAO Y.J., FANG T.H., JI L.W., J. Sol-Gel Sci. Technol., 69 (2014), 299.
• [6] XUE H., ZHU Y., GE M., J. Mater. Sci.: Mater. Electron., 28 (2017), 9032.
• [7] MENG Y., ZHAO W. CHEN., J. Appl. Phys. A, 122 (2016), 636.
• [8] CHEN D.C., LIU Q.L., Rare Met., 33 (2014), 203.
• [9] CHEN D.C., SONG Z., LIU Z.G., DENG Z.H., WU L., CAO Y.G., LIU Q.L., Rare Met., 33 (2014), 80.
• [10] SHEN X., ZHANG D.F., FAN X.W., HU G.S., BIAN X.B., YANG L., J. Mater. Sci.: Mater. Electron., 27 (2016), 976.
• [11] GAME D.N., INGALE N.B., OMANWAR S.K., J. Mater. Sci.: Mater. Electron., 28 (2017), 915.
• [12] MANWAR Y.P., PALASPAGAR R.S., SONEKAR R.P., OMANWAR S.K., J. Mater. Sci.: Mater. Electron., 28 (2017), 994.
• [13] CHEN D.C., LIU Z.G., DENG Z.H., WANG C., CAO Y.G., LIU Q.L., Rare Met., 33 (2014), 348.
• [14] XIN S., ZHOU F., WANG C., LI Z., YUAN S., ZHU G., J. Mater. Sci.: Mater. Electron., 28 (2017), 19134.
• [15] GAO X., LEI L., YIN Y., XIE J., WANG Y., GU W., Russ. J. Phys. Chem., 88 (2014), 1232.
• [16] ZHANG W., YIN X., LIU Y., ZHANG N., ZHAO G., HOU J., FANG Y., J. Mater. Sci.: Mater. Electron., 27 (2016), 5357.
• [17] ZHOU L., HUANG J., MO F., Mater. Sci.-Poland, 32 (2014), 88.
• [18] RAJESH D., RATNAKARAM Y.C., NAIDU M.D., Indian. J. Phys., 88 (2014), 1291.
• [19] BAJAJ N.S., KOPARKAR K.A., NAGPURE P.A. OMANWAR S.K., J. Opt., 46 (2017), 91.
• [20] YEN W.M., WEBER M.J., Inorganic Phosphors: Compositions, Preparation and Optical Properties, CRC Press, LLC, 2000 N.W. Corporate Blvd., Boca Raton Florida 33431, 2004.

Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).