Nichia Corporation

Shinpei Kinoshita

Hiroto Tamaki

Yoshinori Murazaki

Suguru Takashima

Masatoshi Kameshima

Junji Takeichi

A lamp includes a light-emitting body that converts electric energy into light energy and a translucent glass covering the light-emitting body, wherein a phosphor layer is provided on at least inner or outer surface of the translucent glass. The phosphor layer includes a fluorescent material including a first phosphor that at least partially converts energy emitted by an excitation source, which emits ultraviolet having a wavelength of about 365 nm, to a first emission spectrum that is different from the energy, and a second phosphor that at least partially converts the first emission spectrum to a second emission spectrum. Peak wavelengths of the emission spectrum of the first and second phosphors have a relation of complementary colors so that when the light created due to the peak wavelengths of the first and second phosphors are mixed, the resulting light is in the white region.

Fluorescent material and light-emitting device

A light emitting device that light of various colors by blending lights emitted by two or more kinds of fluorescent materials which are substantially directly excited by light emitted by an excitation source having principal emission peak in a range from 250 nm to 500 nm. Each of the fluorescent materials is of a direct-transition type.

Light emitting device

A fluorescent material includes first and second phosphors. The first phosphor is a light-storing phosphor, which is represented by the general formula (MEuQ)AlO, wherein M is one type selected from the group consisting of Mg, Ca, Ba, Sr and Zn; Q is one type selected from the group consisting of Pr, Nd, Dy, Er and Ho; a is a number that satisfies 0.0001&#x2266;a&#x2266;0.5; and b is a number that satisfies 0.010&#x2266;b&#x2266;0.5. When the fluorescent material is excited for about 15 minutes by ultraviolet irradiation having about 365.0 nm wavelength with an intensity of 0.5 mW/cm, and the color of the afterglow of the fluorescent material is measured 1 minute and 10 minutes after excitation is terminated, an amount of change between chromaticity measured 1 minute after excitation and that measured 10 minutes is in the range of &#x2212;0.001&#x2266;x&#x2266;0.009 and &#x2212;0.009&#x2266;y&#x2266;0.006.

The present invention provides a fluorescent material comprising a light-storing first phosphor that at least partially converts energy emitted by an excitation source to a first emission spectrum that is different from the energy, and a second phosphor that at least partially converts the first emission spectrum to a second emission spectrum that is different from the first emission spectrum; a lamp equipped with such a fluorescent material; a light-emitting device that produces a whitish afterglow, comprising such a fluorescent material for converting the emission by an LED chip; and a display unit comprising a display equipped with a plurality of such light-emitting devices.

Growing community of inventors

Anan, Japan

Shinpei Kinoshita