Abstract: The present invention provides a method of operating a fuel cell, which method enables a polymer electrolyte membrane to be humidified sufficiently under high-temperature conditions, and can obtain excellent power generation performance. The present invention is a method of operating a fuel cell including a membrane electrode assembly containing an electrolyte membrane, catalyst layers, and gas diffusion layers, the method including a step of setting the operating temperature of the fuel cell at 100° C. or more, wherein, in the step, the relative humidity of supply gas to be supplied to the fuel cell is 70% or more, and the back pressure of the supply gas is 330 kPa or more.

Abstract: A light emission body capable of simultaneously improving spot feature and color unevenness of illumination light is provided. A light emission body (6) according to one embodiment of the present invention includes a fluorescent substance layer (61) having a light irradiation surface (61a) irradiated with laser light (L1) and a light emitting surface (61b) emitting the laser light (L1) and fluorescence (L2), a light absorption layer (62) that blocks the laser light (L1) and the fluorescence (L2) emitted from the light emitting surface (61b), and a scattering layer (63) that scatters the laser light (L1) and the fluorescence (L2) which are not blocked by the light absorption layer (62).

Abstract: A wavelength conversion member that includes a single crystal phosphor and has a high yield rate is provided. A light emitting unit (1) is a wavelength conversion member that converts a wavelength of a laser light output from a laser light source and includes a phosphor layer (1a) formed of a single crystal phosphor. A plane orientation of a principal plane (1b), which has an area larger than those of divided planes, of the phosphor layer is {111}, and a plane orientation of some divided planes out of the plurality of divided planes is {1-10}.

Abstract: A wavelength conversion member that includes a single crystal phosphor and has a high yield rate is provided. A light emitting unit (1) is a wavelength conversion member that converts a wavelength of a laser light output from a laser light source and includes a phosphor layer (1a) formed of a single crystal phosphor. A plane orientation of a principal plane (1b), which has an area larger than those of divided planes, of the phosphor layer is {111}, and a plane orientation of some divided planes out of the plurality of divided planes is {1-10}.

Abstract: Efficiency of extracting fluorescent light in a desired direction is improved. A light emitting portion (12) of a light emitting device (10) includes a gap present inside thereof, the gap having a width that is one-tenth or less of the wavelength of laser light. An excitation-light transmitting film (13) that transmits laser light and that reflects fluorescent light is provided on a side where a light reception surface (12a) that receives laser light is present. A fluorescent-light transmitting film (14) that reflects laser light and that transmits fluorescent light is provided on a side where an emission surface (12b) that emits fluorescent light is present.

Abstract: In a light emitting section, a phosphor layer including a first phosphor particle which receives excitation light and emits fluorescence with a first peak wavelength and a phosphor layer including a second phosphor particle which receives the excitation light and emits fluorescence with a second peak wavelength are stacked. In the light emitting section, when an upper surface is a surface from which illumination light is mostly emitted, the illumination light including the fluorescence emitted from the first phosphor particle and the fluorescence emitted from the second phosphor particle, a reflective member to reduce leakage of fluorescence is provided on a side surface of the light emitting section.

Abstract: A light emission body capable of simultaneously improving spot feature and color unevenness of illumination light is provided. A light emission body (6) according to one embodiment of the present invention includes a fluorescent substance layer (61) having a light irradiation surface (61a) irradiated with laser light (L1) and a light emitting surface (61b) emitting the laser light (L1) and fluorescence (L2), a light absorption layer (62) that blocks the laser light (L1) and the fluorescence (L2) emitted from the light emitting surface (61b), and a scattering layer (63) that scatters the laser light (L1) and the fluorescence (L2) which are not blocked by the light absorption layer (62).

Abstract: When a phosphor layer formed of a small-gap phosphor plate is used, color irregularity of illumination light emitted from a light-emitting device is reduced. The light-emitting device (100) which emits laser light (L1) as part of illumination light includes a semiconductor laser (10a to 10c) which emits the laser light (L1), which is visible light, a phosphor layer (1a) formed of a small-gap phosphor plate which emits a fluorescence (L2) upon reception of the laser light (L1) emitted from the semiconductor laser (10a to 10c), and an excitation light distribution control unit (1b) which controls light distribution of the laser light (L1) and guides the laser light (L1) to inside of the phosphor layer (1a). The small-gap phosphor plate is a phosphor plate in which a gap that is present inside has a width equal to or longer than 0 nm and equal to or shorter than one tenths of a wavelength of the laser light (L1).

Abstract: A light-emitting device includes a light-emitting portion that emits fluorescence in response to excitation light incident on a surface of the light-emitting portion, and a reflector that defines a light-emitting region on the surface of the light-emitting portion, the fluorescence being emitted from the light-emitting region. The excitation light has a top-hat energy intensity distribution on the surface of the light-emitting portion.

Abstract: A light-emitting unit according to the present invention includes: a fluorescent section for emitting light upon irradiation with a laser beam; and a wavelength selection filter being provided so as to face the fluorescent section. The wavelength selection filter reflects the laser beam toward the fluorescent section and transmits fluorescence emitted from the fluorescent section.

Abstract: In a light emitting section, a phosphor layer including a first phosphor particle which receives excitation light and emits fluorescence with a first peak wavelength and a phosphor layer including a second phosphor particle which receives the excitation light and emits fluorescence with a second peak wavelength are stacked. In the light emitting section, when an upper surface is a surface from which illumination light is mostly emitted, the illumination light including the fluorescence emitted from the first phosphor particle and the fluorescence emitted from the second phosphor particle, a reflective member to reduce leakage of fluorescence is provided on a side surface of the light emitting section.

Abstract: A light-emitting device includes a light-emitting portion that emits fluorescence in response to excitation light incident on a surface of the light-emitting portion, and a reflector that defines a light-emitting region on the surface of the light-emitting portion, the fluorescence being emitted from the light-emitting region. The excitation light has a top-hat energy intensity distribution on the surface of the light-emitting portion.

Abstract: A light-emitting device includes a light-emitting section, a lens, and a movement control section, the movement control section changing an illumination position and a spot size of a laser beam in the light-emitting section by changing a relative position of the lens with respect to the light-emitting section.

Abstract: In a light emitting section, a phosphor layer including a first phosphor particle which receives excitation light and emits fluorescence with a first peak wavelength and a phosphor layer including a second phosphor particle which receives the excitation light and emits fluorescence with a second peak wavelength are stacked. In the light emitting section, when an upper surface is a surface from which illumination light is mostly emitted, the illumination light including the fluorescence emitted from the first phosphor particle and the fluorescence emitted from the second phosphor particle, a reflective member to reduce leakage of fluorescence is provided on a side surface of the light emitting section.

Abstract: A light-emitting device includes a light-emitting portion that emits fluorescence in response to excitation light incident on a surface of the light-emitting portion, and a reflector that defines a light-emitting region on the surface of the light-emitting portion, the fluorescence being emitted from the light-emitting region. The excitation light has a top-hat energy intensity distribution on the surface of the light-emitting portion.

Abstract: A headlamp includes the laser chip which emits excitation light, a light-emitting section which contains a phosphor, and an optical rod. The excitation light emitted from the laser chip is optically guided by the optical rod, and the light output from the optical rod enters the light-emitting section. An edge is present in the light intensity distribution of the light-emitting section.

Abstract: In a light emitting section, a phosphor layer including a first phosphor particle which receives excitation light and emits fluorescence with a first peak wavelength and a phosphor layer including a second phosphor particle which receives the excitation light and emits fluorescence with a second peak wavelength are stacked. In the light emitting section, when an upper surface is a surface from which illumination light is mostly emitted, the illumination light including the fluorescence emitted from the first phosphor particle and the fluorescence emitted from the second phosphor particle, a reflective member to reduce leakage of fluorescence is provided on a side surface of the light emitting section.

Abstract: A light-emitting unit according to the present invention includes: a fluorescent section for emitting light upon irradiation with a laser beam; and a wavelength selection filter being provided so as to face the fluorescent section. The wavelength selection filter reflects the laser beam toward the fluorescent section and transmits fluorescence emitted from the fluorescent section.

Abstract: A light-emitting device includes a light-emitting portion that emits fluorescence in response to excitation light incident on a surface of the light-emitting portion, and a reflector that defines a light-emitting region on the surface of the light-emitting portion, the fluorescence being emitted from the light-emitting region. The excitation light has a top-hat energy intensity distribution on the surface of the light-emitting portion.

Abstract: A headlamp includes the laser chip which emits excitation light, a light-emitting section which contains a phosphor, and an optical rod. The excitation light emitted from the laser chip is optically guided by the optical rod, and the light output from the optical rod enters the light-emitting section. An edge is present in the light intensity distribution of the light-emitting section.