×

Illumination method and light-emitting device

  • US 9,954,149 B2
  • Filed: 04/24/2017
  • Issued: 04/24/2018
  • Est. Priority Date: 09/02/2011
  • Status: Active Grant
First Claim
Patent Images

1. A light-emitting device comprising at least a semiconductor light-emitting element as a light-emitting element, whereinthe light-emitting device includes a light-emitting element which has a peak within a short wavelength range from 380 nm to 495 nm, a light-emitting element which has a peak within an intermediate wavelength range from 495 nm to 590 nm, and a light-emitting element which has a peak within a long wavelength range from 590 nm to 780 nm,the light-emitting device includes at least one each of the light-emitting elements in said respective wavelength ranges,the light-emitting device includes two or more of the light-emitting elements in at least one selected from said wavelength ranges,the light emitted from the light-emitting device in the radiant direction satisfies (1)′

  • and (2) below;

    (1)′

    if an a* value and a b* value in CIE 1976 L*a*b* color space of 15 Munsell renotation color samples from #01 to #15 listed below when mathematically assuming illumination by the light emitted from the light-emitting device in the radiant direction are respectively denoted by a*nSSL and b*nSSL (where n is a natural number from 1 to

         15), andan a* value and a b* value in CIE 1976 L*a*b* color space of the 15 Munsell renotation color samples when mathematically assuming illumination by a reference light that is selected according to a correlated color temperature TSSL (K) of the light emitted from the light-emitting device in the radiant direction are respectively denoted by a*nref and b*nref (where n is a natural number from 1 to

         15), then each saturation difference Δ

    Cn satisfies


    3.8≤

    Δ

    Cn

    18.6 (where n is a natural number from 1 to

         15);

    if a maximum saturation difference value is denoted by Δ

    Cmax and a minimum saturation difference value is denoted by Δ

    Cmin, then a difference |Δ

    Cmax

    Δ

    Cmin| between the maximum saturation difference value and the minimum saturation difference value satisfies
    2.8≤



    Cmax

    Δ

    C
    min|≤

    19.6,
    where Δ

    Cn=√

    {(a*nSSL)2+(b*nSSL)2}−



    {(a*nref)2+(b*nref)2}with the 15 Munsell renotation color samples being;

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×