Color rendering and luminous efficacy of white LED spectra

@inproceedings{Ohno2004ColorRA,
  title={Color rendering and luminous efficacy of white LED spectra},
  author={Yoshihiro Ohno},
  booktitle={SPIE Optics + Photonics},
  year={2004}
}
  • Y. Ohno
  • Published in SPIE Optics + Photonics 5 August 2004
  • Physics
White LED spectra for general lighting should be designed for high luminous efficacy as well as good color rendering. Multi-chip and phosphor-type white LED models were analyzed by simulation on their color characteristics and luminous efficacy of radiation, compared with those of conventional light sources for general lighting. Color rendering characteristics were evaluated based on the CIE Color Rendering Index (CRI), using not only Ra but also the special color rendering indices Ri as well… 

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References

SHOWING 1-10 OF 10 REFERENCES

Color rendering properties of LED light sources

A laboratory human factors experiment was conducted to understand the color rendering properties of various LED-based reading lights. Human subjects rated their preference for a given scene

Color Rendering: Asking the Question

Two white lights may have the same chromaticity, and yet when used to light an array of objects may differ in their ability to reveal colors. For example, any white light can be matched by a mixture

Visual clarity and feeling of contrast

The visual clarity of a lighting environment is significantly affected by changing the general color rendering index (Ra) of its illumination. This effect has been studied by a number of researchers,

A Validation of the Color-Preference Index

Four fluorescent lamps of daylight chromaticity, and with varying Color-Preference Index (CPI), illuminated an array of fruit, vegetables, breads and meat. The lamps were rated in order of preference

A flattery index for artificial illuminants

  • Illuminating Engineering,
  • 1967

Color Rendering: Asking the Questions

  • Color Res. Appl
  • 2003

CIE 135/2:1999, Colour rendering (TC 1-33 closing remarks)

    CIE 122-1996, The relationship between digital and colorimetric data for computer-controlled CRT displays

      Colour rendering, Past – Present – Future

      • Proc. International Lighting and Colour Conf., 50th anniversary of SANCI,
      • 2003

      3:1995, Method of Measuring and Specifying Colour Rendering Properties of Light Sources

      • CIE 13