White LEDs with limit luminous efficacy

Journal Article · Fri Jan 15 04:00:00 EST 2016 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4937863· OSTI ID:22494447

Lisitsyn, V. M.; Yangyang, Ju ^[1]; Lukash, V. S. ^[2]

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1. National Research Tomsk Polytechnic University, 30 Lenin Av., Tomsk, 634050 (Russian Federation)
2. JSC Research Institute of Semiconductor Devices, 99a Krasnoarmeyskaja St., Tomsk, 634050 (Russian Federation)

In most promising widespread gallium nitride based LEDs emission is generated in the blue spectral region with a maximum at about 450 nm which is converted to visible light with the desired spectrum by means of phosphor. The thermal energy in the conversion is determined by the difference in the energies of excitation and emission quanta and the phosphor quantum yield. Heat losses manifest themselves as decrease in the luminous efficacy. LED heating significantly reduces its efficiency and life. In addition, while heating, the emission generation output and the efficiency of the emission conversion decrease. Therefore, the reduction of the energy losses caused by heating is crucial for LED development. In this paper, heat losses in phosphor-converted LEDs (hereinafter chips) during spectrum conversion are estimated. The limit values of the luminous efficacy for white LEDs are evaluated.

• OSTI ID: 22494447
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1698; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CONVERSION
EFFICIENCY
EMISSION
EXCITATION
GALLIUM NITRIDES
HEAT LOSSES
HEATING
REDUCTION
SPECTRA
VISIBLE RADIATION
YIELDS