Nichia Corporation

Dai Nippon Printing Co., Ltd.

Hiroto Itoi

Yusaku Achi

Ryosuke Wakaki

Shingo Masui

Ken Katsuragi

Atsushi Yamamoto

Takeshi Morikawa

Seiji Tawaraya

Kazuyuki Hino

A backlight unit includes a light-guide plate, a light source, and a phosphor sheet including a red phosphor material. The light source includes blue light emitting diodes, and green semiconductor lasers. The red phosphor material is excited by light from the blue light emitting diodes and emits red light. The phosphor sheet is solid and disposed on a surface of a first principal plane of the light-guide plate to define a first mixing light emission surface on the first principal plane of the light-guide plate from which green light emitted from the green semiconductor lasers and blue light from the blue light emitting diodes are emitted toward the phosphor sheet and a second mixing light emission surface on the phosphor sheet from which red light emitted from the red phosphor material, green light emitted from the green semiconductor lasers, and blue light from the blue light emitting diodes are emitted.

Backlight unit and method of lighiting backlight unit

A backlight unit has a light-guide plate and a light source optically coupled with the light-guide plate, with which light is input from a plane of the light-guide plate and white-light is output from the first principal plane of the light-guide plate. The light source has a plurality of blue light emitting diodes, red phosphor material excited by light from the blue light emitting diodes and emits red light, and a plurality of green semiconductor lasers having emission peaks at green light wavelengths. The red phosphor material is included in a phosphor sheet, and the phosphor sheet is disposed on a surface of the light-guide plate.

Backlight unit and liquid crystal display device

An image display module includes a light emitting device including a nitride semiconductor light-emitting element, as a light source, having an emission peak wavelength in a wavelength range of 240 nm to 560 nm, an Mn-activated red fluorescent material having a maximum excitation wavelength in the wavelength range, an emission peak wavelength of 610 nm to 670 nm, and a half bandwidth of the emission spectrum of 30 nm or less, and a green fluorescent material having an emission peak wavelength in a wavelength range of 510 nm to 550 nm; and a color filter having a blue pixel wherein the difference between the maximum and the minimum value of transmittance at a wavelength range of 420 nm to 460 nm of the spectral transmittance curve is 4% or less.

Image display module with superior white point stability

A backlight unit has a light-guide plate and a light source optically coupled with the light-guide plate, with which light is input from a plane of the light-guide plate and white-light is output from the first principal plane of the light-guide plate. The light source has a plurality of blue light emitting diodes, red phosphor material excited by light from the blue light emitting diodes and emits red light, and a plurality of green semiconductor lasers having emission peaks at green light wavelengths.

Growing community of inventors

Anan, Japan

Hiroto Itoi