Patent ID: 6414426
Filing Date: 2002-07-02
Classification: C09K,H01J

Abstract:
A fluorescent lamp that ensures categorical color perception for surface colors of at least red, green, blue, yellow and white, while improving the luminous efficiency in scotopic vision and mesopic vision or in a wide visual field, the lamp comprising:a first phosphor that has a peak emission wavelength in a first wavelength region of from 530 to 580 nm and a second phosphor that has a peak emission wavelength in a second wavelength region of from 600 to 650 nm; and a third phosphor that has a peak emission in a third wavelength region of from 420 to 530 nm; wherein: dominant radiation is obtained from the first and the second phosphors; the flux emitted by the third phosphor is 4 to 40% of the total flux emitted by the first and the second phosphors; and the correlated color temperature of the lamp light color is at least 3500 K; and Duv, in which Duv is &Dgr;uvÃ—1000 and &Dgr;uv is the distance of the color point from the Plankian locus on the CIE 1960 chromaticity diagram, is 5 to 70.