Journal of Light & Visual Environment
Online ISSN : 1349-8398
Print ISSN : 0387-8805
ISSN-L : 0387-8805
Search
Advanced search
OR
Browse
Search
Volume 11, Issue 2
Displaying 1-7 of 7 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
Lecture
Paper
  • Possibility of Daylight Simulators Composed of Several Monochromatic Radiations
    —Relation Between the Visible Range Metamerism Index and the General Color Rendering Index—
    Takashi ICHIJO, Leo MORI
    1987 Volume 11 Issue 2 Pages 2_14-2_25
    Published: 1987
    Released on J-STAGE: May 20, 2011
    DOIhttps://doi.org/10.2150/jlve.11.2_14
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    The possibility of realizing daylight simulators satisfying the conditions specified in JIS Z8720-1983 and Publication CIE No. 51, with line spectrum sources composed of several monochromatic radiations (lines), was examined by a nonlinear programming technique. It was found possible to realize simulators satisfying: (1) the condition of a visible range metamerism index Mlvis ≤ 0.5 (CIELAB10) with 5 spectral lines, (2) the condition of an ultraviolet range metamerism index Mluv ≤ 1 (CIELAB10) with 3 lines, (3) both Mlvis ≤ 0.5 and Mluv ≤ 1,while the general color rendering index Ra is not sufficiently high, with 6 lines, (4) Ra ≥ 95 (CIE 2nd Edition), while Mlvis is not sufficiently good, with 5 lines, and (5) Mlvis ≤ 0.5,Mluv ≤ 1 and Ra ≥ 95 with 7 lines. (6) Six lines are necessary to realize both Mlvis ≤ 0.5 and Ra ≥ 95, in contrast with 5 lines in cases (1) and (4). It is suggested that daylight simulators in either case (5) or (6) are insufficient to reproduce the color appearance of chromatic fluorescent objects excited by visible range radiation under a natural daylight illuminant.
    View full abstract
    Download PDF (816K)
  • Visual Appearance of Color and Image Quality of Computer-Generated 3-D Transparent Objects
    Masayuki IIZUKA, Yutaka OHE
    1987 Volume 11 Issue 2 Pages 2_26-2_34
    Published: 1987
    Released on J-STAGE: May 20, 2011
    DOIhttps://doi.org/10.2150/jlve.11.2_26
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    Translucent or transparent quality of computer-generated 3-D images with a complex of reflected scene among boundary surfaces may be visualized using a constructive solid geometry model (CSGM) and a ray tracing method (RTM) on a color CRT. Generally, the CSGM is composed of a combination of some primitives and quadratic surfaces. The RTM has been widely used as the principal means for displaying computer-generated 3-D images with reality. The effects of additive and pseudo-subtractive color mixings are compared with a view to examining the visual appearance of color and image quality of transparent objects on a color CRT. The relation between the degree of transparency and the value of depth level: a kind of parameter for taking stock of the total number of times of specular reflection at the surface of opaque objects and/or that of reflection and refraction at the border of transparent media is discussed from a viewpoint of color rendering and color shift.
    View full abstract
    Download PDF (1885K)
Research Note
  • Glare and Illuminance as Causes of Discomfort in an Interior
    S. KANAYA, H. MANABE, K. NARISADA
    1987 Volume 11 Issue 2 Pages 2_35-2_40
    Published: 1987
    Released on J-STAGE: May 20, 2011
    DOIhttps://doi.org/10.2150/jlve.11.2_35
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    The effects of the glare level and the illuminance level on visual comfort and discomfort experienced by the observers were investigated in a full scale office room located in the laboratory. Sixty-one observers, who were not informed of the real aim of the observations, aged from 20 to 41, were asked to rate their impressions as to various lighting conditions in the room on the Semantic Differential Rating Scales consisting of 13 pairs of adjectives. As a result, the influences of the glare and the illuminance level on which adjectives were chosen by the observers were analyzed statistically. We found that the illuminance had a greater influence on the comfort of the interior atmosphere than did the luminance of the luminaires. Also, the luminance had greater influence on the psychological tenseness of the interior atmosphere than on the comfort of the interior.
    View full abstract
    Download PDF (1077K)
  • Monte Carlo Simulation of Illuminance Distribution in a Cubic Interior with Interreflection
    Masayoshi NAGATA
    1987 Volume 11 Issue 2 Pages 2_41-2_48
    Published: 1987
    Released on J-STAGE: May 20, 2011
    DOIhttps://doi.org/10.2150/jlve.11.2_41
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    Monte Carlo simulation (MCS) can be a powerful technique to obtain practical illuminance distribution in an interior, particularly for complicated one with interreflections. Applications to the two dimensional problems within a cross section of an interior of infinite length, which are most convenient for MCS of course, have already been reported. In this paper, a fundamental study for the illuminance distribution in a cubic interior with various reflectances is carried out by means of Monte Carlo simulation. The illuminance distribution obtained by MCS inevitably includes statistical fluctuation. However, asymmetry and uneven distribution due to the statistical procedure of MCS can be reduced by increasing the number of emitting photon bundles and the interreflection. Under several model interreflections, it is shown that the MCS results that emitting the photon bundles of 6×106 in a cubic interior of 6 m2 composed of 6×1,600 area elements can provide illuminance distribution being precise enough to be used for the practical lighting design.
    View full abstract
    Download PDF (730K)
Installation Report
Committee Report
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top