Patent ID: 10669478

Abstract:
The invention provides a lighting device (100) comprising a solid state light source (10) configured to provide blue light (11) having a dominant wavelength selected from the range of 440-490 nm, a first luminescent material (210) configured to convert part of the blue light (11) into first luminescent material light (211) having intensity in one or more of the green and yellow having a CIE u′ (211), and a second luminescent material (220) configured to convert part of one or more of the blue light (11) and the first luminescent material light (211) into second luminescent material light (221) having intensity in one or more of the orange and red having a CIE u′ (221), wherein the first luminescent material (210) and the second luminescent material (220) are selected to provide said first luminescent material light (211) and said second luminescent material light (221) defined by a maximum ratio of CIE u′ (211) and CIE u′ (221) being CIE u′(221)=1.58*CIE u′(211)+0.255, and a minimum ratio of CIE u′ (211) and CIE u′ (221) being CIE u′(221)=2.3*CIE u′(211)+0.04.