Nichia Corporation

Kazushige Fujio

Mika Amiya

Kenji Asai

Sadakazu Wakui

Makiko Iwasa

Tomokazu Suzuki

Masaki Kondo

Mika Matsumoto

Miyuki Kurata

Koji Kajikawa

Provided is a light-emitting device, a lighting appliance, and a street light that emit light with minimal negative effects on the behavior of sea turtles and which makes irradiated objects easily visible to humans. The light-emitting device includes a light-emitting element having an emission peak wavelength within a range from 400 nm to 490 nm; and a first phosphor having an emission peak wavelength within a range from 570 nm to 680 nm, wherein the light-emitting device, lighting appliance, and street light emit light that has a correlated color temperature of 1950 K or less, an average color rendering index Ra of 40 or greater, a full width at half maximum of an emission spectrum indicating a maximum emission intensity in an emission spectrum of the light-emitting device of 110 nm or less, and a sea turtle light attraction index T derived from Equation (1) of 0.416 or less.

Light-emitting device, lighting appliance, and street light

A light emitting device comprises a light emitting element having a light emission peak wavelength in a range of 400 nm or more and 490 nm or less and a first fluorescent material having a light emission peak wavelength in a range of 570 nm or more and 680 nm or less, and emits light having a correlated color temperature being 1,950 K or less, an average color rendering index Ra being 70 or more, a full width at half maximum of a light emission peak having the maximum light emission intensity being 110 nm or less, and a ratio B/L of an effective radiance B to a luminance L being 0.151 or less, wherein the luminance of light emitted by the light emitting device in a range of 300 nm or more and 800 nm or less when B and L is as defined in the disclosure.

Light emitting device, light fixture, and street light

A light emitting device includes a light emitting element having an emission peak wavelength in a range of 380 nm to 420 nm and a fluorescent member including at least one fluorescent material that is excited by light from the light emitting element for light emission, wherein a mixture of light from the light emitting element and light from the fluorescent material has a correlated color temperature in a range of 2000 K to 7500 K as measured according to JIS Z8725, and the light emitting device has a spectral distribution in which, when the integral value over a wavelength range of 380 nm to 780 nm is normalized to 100%, the proportion of an integral value over a wavelength range of 380 nm to 420 nm is 15% or more, and the ratio a as defined by the expression (1) is 0.9 or more and 1.6 or less.

Light emitting device

A light emitting device includes a first light source containing a first light emitting element, and a second light source containing a second light emitting element and a second fluorescent material, the first light source emits light in a region that is demarcated in a chromaticity diagram of the CIE 1931 color coordinate system by a first straight line connecting a first point having x,y of 0.280, 0.070 in the chromaticity coordinate and a second point having x,y of 0.280, 0.500 in the chromaticity coordinate, a second straight line connecting the second point and a third point having x,y of 0.013, 0.500 in the chromaticity coordinate, a purple boundary extending from the first point toward a direction in which x decreases in the chromaticity coordinate, and a spectrum locus extending from the third point toward a direction in which y decreases in the chromaticity coordinate, in a light emission spectrum, a light emission intensity ratio I/Iof a light emission intensity Iat a wavelength of 490 nm with respect to a light emission intensity Iat a maximum light emission peak wavelength of the first light emitting element is in a range of 0.22 or more and 0.95 or less, the second light source emits light having a color deviation duv from a blackbody radiation locus in a range of &#x2212;0.02 or more and 0.02 or less measured according to JIS Z8725 with a correlated color temperature in a range of 1,500 K or more and 8,000 K or less in a chromaticity diagram of the CIE 1931 color coordinate system, and the light emitting device emits mixed color light of light emitted from the first light source and light emitted from the second light source.

A light emitting device comprises a light emitting element having a light emission peak wavelength in a range of 400 nm or more and 490 nm or less and a first fluorescent material having a light emission peak wavelength in a range of 570 nm or more and 680 nm or less, and emits light having a correlated color temperature being 1,950 K or less, an average color rendering index Ra being 51 or more, a full width at half maximum of a light emission peak having a maximum light emission intensity in a light emission spectrum of the light emitting device being 110 nm or less, and a first glare index Ls1/L that is a ratio of a first effective radiance Ls1 to a luminance L being 0.493 or less, wherein Ls1 and L are as defined in the disclosure.

A light-emitting device is provided. The light-emitting device includes a light-emitting element having a peak light-emitting wavelength in the range of 440 nm to 470 nm, and a fluorescent member. The fluorescent member includes a first fluorescent material having a peak light-emitting wavelength in the range of 480 nm to less than 520 nm, a second fluorescent material having a peak light-emitting wavelength in the range of 520 nm to less than 600 nm, and a third fluorescent material having a peak light-emitting wavelength in the range of 600 nm to 670 nm. The light-emitting device has a ratio of an effective radiant intensity for melatonin secretion suppression to an effective radiant intensity for blue-light retinal damage of 1.53 to 1.70 when the light-emitting device emits light with a correlated color temperature of 2700 K to less than 3500 K; 1.40 to 1.70 when the light-emitting device emits light with a correlated color temperature of 3500 K to less than 4500 K; 1.40 to 1.70 when the light-emitting device emits light with a correlated color temperature of 4500 K to less than 5700 K; and 1.35 to 1.65 when the light-emitting device emits light with a correlated color temperature of 5700 K to 7200 K.

Light-emitting device

A light emitting device includes: a light emitting element having an emission peak wavelength in a range of 430 nm to 470 nm; and a fluorescent member including a fluorescent material that is excited by light from the light emitting element for light emission, wherein a mixture of light from the light emitting element and light from the fluorescent material has a correlated color temperature in a range of 1500 K to 11000 K, as measured according to JIS Z8725, the color deviation dthat is a deviation from the black body radiation track on the CIE1931 chromaticity diagram of the mixture of light and is measured according to JIS Z8725 falls within a range of more than 0 to 0.02 or less at a correlated color temperature of 1500 K to 11000 K, and when a value calculated by integrating a product of the spectral distribution of the mixture of light and each relative intensity of a human standard spectral luminous efficiency over a wavelength range of a human visible region is referred to as an integral value a and when a value calculated by integrating a product of the spectral distribution of the mixture of light and each relative intensity of an insect spectral luminous efficiency over a wavelength range where insects exhibit positive phototaxis is referred to as an integral value b, the insect attracting index I defined as a ratio of the integral value b to the integral value a (b/a) is 50% or more and 99% or less of the insect attracting index Iat the time when the color deviation dis 0.

A light emitting device includes a first light source containing a first light emitting element, and a second light source containing a second light emitting element and a second fluorescent material, the first light source emits light in a region that is demarcated in a chromaticity diagram of the CIE 1931 color coordinate system by a first straight line connecting a first point having x,y of 0.280,0.070 in the chromaticity coordinate and a second point having x,y of 0.280,0.500 in the chromaticity coordinate, a second straight line connecting the second point and a third point having x,y of 0.013,0.500 in the chromaticity coordinate, a purple boundary extending from the first point toward a direction in which x decreases in the chromaticity coordinate, and a spectrum locus extending from the third point toward a direction in which y decreases in the chromaticity coordinate, in a light emission spectrum, a light emission intensity ratio I/Iof a light emission intensity Iat a wavelength of 490 nm with respect to a light emission intensity Iat a maximum light emission peak wavelength of the first light emitting element is in a range of 0.22 or more and 0.95 or less, the second light source emits light having a color deviation duv from a blackbody radiation locus in a range of &#x2212;0.02 or more and 0.02 or less measured according to JIS Z8725 with a correlated color temperature in a range of 1,500 K or more and 8,000 K or less in a chromaticity diagram of the CIE 1931 color coordinate system, and the light emitting device emits mixed color light of light emitted from the first light source and light emitted from the second light source.

Provided is a light emitting device, comprising: a light emitting element including a light emission peak wavelength in a range of 440 nm or more and 470 nm or less; a first fluorescent material having a light emission peak wavelength in a range of 480 nm or more and 518 nm or less; a second fluorescent material having a light emission peak wavelength in a range of 510 nm or more and less than 590 nm and having an x value of the chromaticity coordinate in CIE1931 in a range of 0.27 or more and 0.40 or less; and a third fluorescent material having a light emission peak wavelength in a range of 590 nm or more and 670 nm or less. The light emitting device is capable of reducing the human eye fatigue and having a light emission spectrum with excellent visual work.

Light emitting device and lighting fixture provided with the same

A light emitting device includes a light emitting element having an emission peak wavelength in a range of 380 nm or more and 490 nm or less, and a red fluorescent material which is excited by the light from the light emitting element to emit light having at least one light emission peak wavelength in a range of 580 nm or more and 680 nm or less, wherein a ratio of the photon flux R of red light in a range of 620 nm or more and 700 nm or less to the photon flux B of blue light in a range of 400 nm or more and 490 nm or less, R/B, is in a range of more than 20 and 200 or less.

Light emitting device and plant cultivation method

Provided are a light emitting device and an illumination device. The light emitting device is provided with a light emitting element having a light emission peak wavelength in a wavelength range of 380 nm or more and 490 nm or less, a first fluorescent material which is excited by the light from the light emitting element to emit light having at least one light emission peak wavelength in a wavelength range of 580 nm or more and less than 680, and a second fluorescent material which is excited by the light from the light emitting element to emit light having at least one light emission peak wavelength in a wavelength range of 680 nm or more and 800 nm or less, wherein a ratio R/B of a photon flux R of red light in a wavelength range of 620 nm or more and less than 700 nm to a photon flux B of blue light in a wavelength range of 400 nm or more and 490 nm or less is more than 4 and 50 or less, a ratio R/Fr of the photon flux R to a photon flux Fr of far-red light in a wavelength range of 700 nm or more and 780 nm or less is 0.1 or more and 10 or less, and the second fluorescent material contains at least one fluorescent material selected from the group consisting of a first aluminate fluorescent material and a second aluminate fluorescent material.

Light emitting device, illumination device and plant cultivation method

Provided is a light emitting device that includes a light emitting element having a light emission peak wavelength ranging from 380 nm to 490 nm, and a fluorescent material excited by light from the light emitting element and emitting light having at a light emission peak wavelength ranging from 580 nm or more to less than 680 nm. The light emitting device emits light having a ratio R/B of a photon flux density R to a photon flux density B ranging from 2.0 to 4.0 and a ratio R/FR of the photon flux density R to a photon flux density FR ranging from 0.7 to 13.0, the photon flux density R being in a wavelength range of 620 nm or more and less than 700 nm, the photon flux density B being in a wavelength range of 380 nm or more and 490 nm or less, and the photon flux density FR being in a wavelength range of 700 nm or more and 780 nm or less.

Growing community of inventors

Tokushima, Japan

Kazushige Fujio