Analysis of junction temperature and modification of luminous flux degradation for white LEDs in a thermal accelerated reliability test

Hong-Liang Ke; Lei Jing; Jian Hao; Qun Gao; Yao Wang; Xiao-xun Wang; Qiang Sun; Zhi-Jun Xu

doi:10.1364/AO.55.005909

Applied Optics
Vol. 55,
Issue 22,
pp. 5909-5916
(2016)
•https://doi.org/10.1364/AO.55.005909

Analysis of junction temperature and modification of luminous flux degradation for white LEDs in a thermal accelerated reliability test

Hong-Liang Ke, Lei Jing, Jian Hao, Qun Gao, Yao Wang, Xiao-xun Wang, Qiang Sun, and Zhi-Jun Xu

Not Accessible

Your library or personal account may give you access

Get PDF
Email
Share
Get Citation
Copy Citation Text
Hong-Liang Ke, Lei Jing, Jian Hao, Qun Gao, Yao Wang, Xiao-xun Wang, Qiang Sun, and Zhi-Jun Xu, "Analysis of junction temperature and modification of luminous flux degradation for white LEDs in a thermal accelerated reliability test," Appl. Opt. 55, 5909-5916 (2016)

Export Citation
- BibTex
- Endnote (RIS)
- HTML
- Plain Text
Citation alert
Save article

Abstract

An accelerated aging test is the main method in evaluation of the reliability of light-emitting diodes (LEDs), and the first goal of this study is to investigate how the junction temperature (Tj) of the LED varies during accelerated aging. The Tj measured by the forward voltage method shows an upward trend over the aging time, which gives a variation about 6°C–8°C after 3,000 h of aging under an ambient temperature of 80°C. The second goal is to investigate how the variation of Tj affects the lifetime estimation. It is verified that at a certain aging stage, as Tj increases, the normalized luminous flux linearly decreases with variation rate of microns ( $μ$ ) (1/°C). Then, we propose a method to modify the luminous flux degradation with the Tj and $μ$ to meet the requirements of a constant degradation rate in the data fitting. The experimental results show that with the proposed method, the accelerated lifetimes of samples are bigger than that of the current method with increment values from 8.8% to 21.4% in this research.

Full Article | PDF Article

More Like This

Comparison of online and offline tests in LED accelerated reliability tests under temperature stress

Hong-Liang Ke, Lei Jing, Qun Gao, Yao Wang, Jian Hao, Qiang Sun, and Zhi-Jun Xu
Appl. Opt. 54(33) 9906-9910 (2015)

Prediction of lifetime by lumen degradation and color shift for LED lamps, in a non-accelerated reliability test over 20,000 h

Jian Hao, Hong-Liang Ke, Lei Jing, Qiang Sun, and Ren-Tao Sun
Appl. Opt. 58(7) 1855-1861 (2019)

Disparity between online and offline tests in accelerated aging tests of LED lamps under electric stress

Yao Wang, Lei Jing, Hong-Liang Ke, Jian Hao, Qun Gao, Xiao-xun Wang, Qiang Sun, and Zhi-Jun Xu
Appl. Opt. 55(27) 7511-7516 (2016)

Previous Article Next Article

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (14)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Tables (3)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (11)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Ambient Temperature (°C)	Voltage (V)	Tj (°C)	Luminous Flux (lm)
25	$29.6729 \pm 0.0075$	$59.6 \pm 0.31$	$276.0 \pm 0.7$
35	$29.3888 \pm 0.0068$	$71.3 \pm 0.28$	$268.2 \pm 0.8$
45	$29.1873 \pm 0.0072$	$79.6 \pm 0.30$	$262.8 \pm 0.6$
55	$28.9275 \pm 0.0056$	$90.3 \pm 0.23$	$254.7 \pm 0.7$
65	$28.6289 \pm 0.0085$	$102.6 \pm 0.35$	$249.1 \pm 0.6$
75	$28.4177 \pm 0.0061$	$111.3 \pm 0.25$	$244.0 \pm 0.5$
85	$28.1214 \pm 0.0055$	$123.5 \pm 0.23$	$235.4 \pm 0.6$

Aging Time (h)	Linear Fitting	R-square
0	$V = - 0.02484 \times Tj + 31.12$	0.9953
500	$V = - 0.02052 \times Tj + 30.99$	0.9974
1,000	$V = - 0.01813 \times Tj + 30.79$	0.9952
1,500	$V = - 0.01603 \times Tj + 30.79$	0.9981
2,000	$V = - 0.01412 \times Tj + 30.56$	0.9971
2,500	$V = - 0.01253 \times Tj + 30.53$	0.9958
3,000	$V = - 0.01181 \times Tj + 30.40$	0.9962

	$μ$ (1/°C)
	0 h	500 h	1,000 h	1,500 h	2,000 h	2,500 h	3,000 h	Average
Sample 1	−0.00226	−0.00256	−0.00241	−0.00235	−0.00229	−0.00242	−0.00221	−0.00236
Sample 2	−0.00212	−0.00235	−0.00225	−0.00208	−0.00235	−0.00225	−0.00215	−0.00220
Sample 3	−0.00222	−0.00201	−0.00210	−0.00208	−0.00200	−0.00213	−0.00223	−0.00211
Sample 4	−0.00219	−0.00245	−0.00241	−0.00236	−0.00234	−0.00221	−0.00212	−0.00230
Sample 5	−0.00231	−0.00221	−0.00240	−0.00245	−0.00238	−0.00250	−0.00238	−0.00238

Ambient Temperature (°C)	Voltage (V)	Tj (°C)	Luminous Flux (lm)
25	$29.6729 \pm 0.0075$	$59.6 \pm 0.31$	$276.0 \pm 0.7$
35	$29.3888 \pm 0.0068$	$71.3 \pm 0.28$	$268.2 \pm 0.8$
45	$29.1873 \pm 0.0072$	$79.6 \pm 0.30$	$262.8 \pm 0.6$
55	$28.9275 \pm 0.0056$	$90.3 \pm 0.23$	$254.7 \pm 0.7$
65	$28.6289 \pm 0.0085$	$102.6 \pm 0.35$	$249.1 \pm 0.6$
75	$28.4177 \pm 0.0061$	$111.3 \pm 0.25$	$244.0 \pm 0.5$
85	$28.1214 \pm 0.0055$	$123.5 \pm 0.23$	$235.4 \pm 0.6$

Aging Time (h)	Linear Fitting	R-square
0	$V = - 0.02484 \times Tj + 31.12$	0.9953
500	$V = - 0.02052 \times Tj + 30.99$	0.9974
1,000	$V = - 0.01813 \times Tj + 30.79$	0.9952
1,500	$V = - 0.01603 \times Tj + 30.79$	0.9981
2,000	$V = - 0.01412 \times Tj + 30.56$	0.9971
2,500	$V = - 0.01253 \times Tj + 30.53$	0.9958
3,000	$V = - 0.01181 \times Tj + 30.40$	0.9962

Abstract

Cited By

Figures (14)

Tables (3)

Equations (11)

Applied Optics