Effects of phosphor application geometry on white light-emitting diodes

Japanese Journal of Applied Physics, Part 2: Letters

Volumn 45, Issue 33-36, 2006, Pages

  Masui, Hisashi ^a,b   Nakamura, Shuji ^a,b   Denbaars, Steven P ^a,b  

^a University of California   (United States)

^b UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

Absorption saturation; Light emitting diode (LED); Phosphor down conversion; Self absorption; Solid state lighting

Indexed keywords

BINARY MIXTURES; ELECTRIC LAMPS; LIGHT ABSORPTION; LIGHT EMITTING DIODES; SPECTRUM ANALYSIS;

ABSORPTION SATURATION; PHOSPHOR DOWN-CONVERSION; SELF-ABSORPTION; SOLID-STATE LIGHTING;

PHOSPHORS;

EID: 33748782838     PISSN: 00214922     EISSN: 13474065     Source Type: Journal    
DOI: 10.1143/JJAP.45.L910     Document Type: Article

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7. 14 atoms of Ce exist in 1 μg of phosphor. This means a Ce atom receives a photon every ten milliseconds. This rate will compete with the relaxation rate of the phosphor.
8. Since the LED lamps were not spherical, differences in the light path length x in different directions became a concern as discussed later in the text. LED lamps with a crude adjustment in the path length were fabricated as well by applying clear silicone partially within a lamp encapsulation. They indicated the same trend in performance as the homogeneously encapsulated LEDs did.