Great strides have recently been made in the development of white light emitting diodes (LEDs), although perceptible variations remain in the color and brightness of nominally identical products. The objective of this study was to examine color and brightness discriminability between different white LEDs when used as illuminants of colored and achromatic objects. A method of successive comparisons was used to assess discriminability rather than the more typical simultaneous (side-by-side) comparisons using a "same-different" response protocol. Three-dimensional "tolerance zones" were developed based upon discriminability in a chromaticity (u', v') and luminance when illuminating the colored and achromatic objects. These "tolerance zones" could be used to establish specification tolerances for different lighting applications.

Date Published: 26 November 2002
PDF: 12 pages
Proc. SPIE 4776, Solid State Lighting II, (26 November 2002); doi: 10.1117/12.452575

Published in SPIE Proceedings Vol. 4776:
Solid State Lighting II
Ian T. Ferguson; Nadarajah Narendran; Steven P. DenBaars; Yoon-Soo Park, Editor(s)