The Experts below are selected from a list of 1074 Experts worldwide ranked by ideXlab platform

Yasushi Fujimoto - One of the best experts on this subject based on the ideXlab platform.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce 3+ . The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce 3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce3+. The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

Setsuhisa Tanabe - One of the best experts on this subject based on the ideXlab platform.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce 3+ . The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce 3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce3+. The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

  • novel hbox eu 2 activated glass ceramics precipitated with green and red phosphors for high power white led
    IEEE Journal of Selected Topics in Quantum Electronics, 2009
    Co-Authors: Toshihiro Nakanishi, Setsuhisa Tanabe
    Abstract:

    We have obtained Eu2+-doped glass-ceramic phosphors, where the two-phosphor crystals of green and red were precipitated by novel GC preparation "frozen sorbet" method and postceraming process. The as-made GC consisted of glass and spherical beta-Ca2SiO4:Eu2+ crystal phases with size of about 20-40 mum. After ceramization, Ca3Si2O7:Eu2+ crystals were also precipitated in addition to the beta-Ca2SiO4 crystal. The photoluminescence had two broad emission bands: at 515 nm from Eu2+ :beta-Ca2SiO4 and at 600 nm from Eu2+ :Ca3Si2O7. Judging from the cathodoluminescence mapping images of microstructure, two emission bands peaked at 515 and 600 nm were observed from different parts in the GC. With increasing heat-treatment temperature, the color coordinates shifted from green range to center region, which corresponds to pure white in the International Commission on Illumination Chromaticity Diagram. Eu2+-doped calcium silicate GC containing beta-Ca2SiO4 and Ca3Si2O7 are suitable phosphor as the use of phosphor converting white LED with high color rendering.

Shotaro Nishiura - One of the best experts on this subject based on the ideXlab platform.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce 3+ . The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce 3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce3+. The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

Kana Fujioka - One of the best experts on this subject based on the ideXlab platform.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce 3+ . The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce 3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

  • properties of transparent ce yag ceramic phosphors for white led
    Optical Materials, 2011
    Co-Authors: Shotaro Nishiura, Setsuhisa Tanabe, Kana Fujioka, Yasushi Fujimoto
    Abstract:

    Abstract Transparent Ce:YAG ceramic phosphors were synthesized from the oxide powder which was produced by co-preparation method of the hydroxides. The Ce:YAG ceramics had a broad emission band peaked at 530 nm due to the 5d → 4f transition of Ce3+. The transmittances of the samples obtained were 70–87% at 800 nm. The absorption coefficient and emission intensity of Ce3+ were increased with increasing thickness. Under 465 nm LED excitation, the color coordinates of the Ce:YAG ceramics shifted from the blue region to yellow region with increasing sample thickness, passing nearby the theoretical white point in the Chromaticity Diagram. The highest value of luminous efficacy of the ceramic white LED was 73.5 lm/W.

Jean-charles Pinoli - One of the best experts on this subject based on the ideXlab platform.

  • the color logarithmic image processing colip antagonist space and Chromaticity Diagram
    Computational Color Imaging Workshop, 2015
    Co-Authors: Yann Gavet, Johan Debayle, Jean-charles Pinoli
    Abstract:

    The CoLIP framework defines a vectorial space for color images. It is in accordance with the theories of visual perception (Weber, Fechner) as well as Hering’s trichromacy theory. It is mathematically well defined and computationally usable. This article recalls the fundamentals of the LIP framework for graytone images, and introduces the elementary operations of the vectorial structure for color images. It illutrates the representation of the Chromaticity Diagram with color modification application, namely white balance correction and color transfer. The results show that the hull of the Diagram are not modified, but the colors are.

  • The Color Logarithmic Image Processing (CoLIP) antagonist space.
    2015
    Co-Authors: Yann Gavet, Johan Debayle, Jean-charles Pinoli
    Abstract:

    The Color Logarithmic Image Processing (CoLIP) is a mathematical framework for the representation and processing of color images. It is psychophysically well justified since it is consistent with several human visual perception laws and characteristics. It is mathematically and computationally relevant since it allows to consider color images as vectors in an abstract linear space, contrary to the classical color spaces (e.g., RGB and L∗a∗b∗). The first purpose of this book chapter is to present the mathematical fundamentals of the CoLIP together with its main psychophysical connections (Grasmann’s law, color matching functions, Chromaticity Diagram and the Maxwell triangle). The second purpose is to present some basic image processing and analysis techniques for contrast enhancement (histogram equalization, dynamic range maximization, toggle contrast calculation), white balance correction, color transfer, K-means clustering and filtering. Most of them are applied on various original color images in a comparative way between CoLIP, RGB and L∗a∗b∗ color spaces.