ISSN:0361-2317    

DOI:10.1002/col.5080170302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080170303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080170304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractTechnical advances in the forty years since the Stiles‐Burch color‐matching work‐among them the bright split‐field visual colorimeter coupled by quartz light pipe to a spectroradiometer‐allow measurement of an accurate absolute spectral power distribution (SPD) of every viewed light. Furthermore, the ability to measure accurately the power‐content of each spectral constituent of a viewed light has clarified both colorimetric procedures and signficance, for example, of color‐matching functions (CMFs) and tristimulus values. Three disparate sets of three spectral primaries were used throughout the work. This has not been done before, and its use elucidated much of the difficulty (as described by Judd, Stiles, MacAdam, Wyszecki, and others) inherent in traditional colorimetry. Errors in computed chromaticities of sets of 28 visually‐matching lights depend strongly on their spectral content, and are particularly large in the presence of high spectral content in the violet, deep red, and near 500 nm or 580 nm. Peaks of visual efficiency, and minima in chromaticity errors, were found with power in three intermediate spectral regions near 450 nm, 530 nm, and 610 nm. Computed luminance (1964 CIE Standard Observer) and power‐content also depend strongly on spectral content of the visually‐matching white lights. That this is true of luminance is generally unknown. Perceived brightness of single spectral lights in isolation, and of mixtures, was examined at length: As a rule, removing one spectral component from a mixture increases perceived brightness, thus invalidating both luminance andR + G + Bas correlates of brightness. Visual tests of the Grassmann proportionality and additivity assumptions, with highly metameric mixtures, tended to confirm them. Nevertheless, numerous tests‐substituting pairs of actual visually‐matching lights from one primary‐set for pairs from another, which is how “transformation of primaries” is (mathematically) carried out‐led to the inescapable conclusion that the normal human visual system does not honor such transformation. At the same time, numerous indications supported a particular set of primaries as an invariant of the visual system, making transformation needless as well as invalid. Chromaticity errors are not the fault of the particular maximum‐saturation CMFs utilized; the observer's own CMFs do no better, whatever the primary‐set. Soundness of traditional construction of the chromaticity diagram is shown to depend on the primary‐set, breakdown occurring for s

ISSN:0361-2317    

DOI:10.1002/col.5080170305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe CIE luminosity function Vδis based largely upon the spectral sensitivity of normal observers measured by flicker photometry. Nonetheless, it is used to specify illumination for visual tasks in which the performance criterion is not temporal resolution, e.g., acuity tasks. It has recently become clear that different channels in the human visual system detect acuity targets than detect flicker. Furthermore, the flicker and acuity channels have ostensibly different spectral sensitivities. Thus it becomes important to verify that lights equated by a flicker criterion and lights equated by an acuity criterion agree. If the spectral sensitivity measured by flicker and acuity criteria differ, then performance on an acuity task for lights of equal luminance but dissimilar spectral composition will differ. Six monochromatic background fields (460, 500, 550, 580, 600, and 660 nm) were flickermatched to a standard white field. the monochromaticplus‐white‐standard fields were used as backgrounds for 10 cycle/degree monochromatic gratings presented as increments. Four observers participated in the experiment. Excepting the 460 nm condition, the contrast required to detect a grating on flicker‐matched backgrounds is independent of wavelength. Although subserved by different channels, flicker photometric and threshold acuity criteria produce similar spectral sensiti

ISSN:0361-2317    

DOI:10.1002/col.5080170306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractMany interiors may be lit by daylight and artificial light; the CIE color rendering index (CRI) of the sources alone is not a characteristic of the complex situation. It is the purpose of this article to derive the general principles leading to the determination of the CRI distribution in such an interior. the CRI is expressed as a function of the proportion α of the combination, for several types of daylight and artificial light. It is shown that the dependence of the CRI on α is linear for supplementary artificial lightings which have the same chromaticity as daylight. Otherwise, nonlinearities are introduced. the time variation of the CRI is also analyze

ISSN:0361-2317    

DOI:10.1002/col.5080170307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractEquations are given to compute Munsell value from a CIE luminance factor Y. The equations are a very accurate, though not mathematically exact, inversion of the fifth‐order equation adopted by the Optical Society of America as the practical definition of Munsell value. The maximum error in Munsell value is 0.0035. The equations have been employed by the Committee on Appearance of the American Society for Testing and Material

ISSN:0361-2317    

DOI:10.1002/col.5080170308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractA multiple regression analysis is reported to predict L/Y ratios as a function of chromaticity coordinates x, y. the specified variables were selected statistically from the 20 terms of Ψmψn. the quantities Ψ, ψ are the transformed values of x, y, respectively, and 1 ≦ m + n ≦ 5. the contour lines of equal L/Y ratios are estimated in the whole chromaticity gamut including spectral colors by using each of the regression equations with 6, 9, and 20 specified variables. the regression equations with 20 specified variables can satisfactorily predict the corresponding experimental results. In case of regression equations with 6 specified variables, the predicted contour lines are significantly different in shape from those of the corresponding experiments. the same defects are found in the Ware‐Cowan equation only using 4 specified variables recommended by CIE Division 1 for furt

ISSN:0361-2317    

DOI:10.1002/col.5080170309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractAn expansion of the Allen and Goldfinger approach to the prediction of the color of absorbing‐scattering substrates is carried out taking into account the effect of optical anisotropy of fibers and definite values of the indices of refraction in the visible spectral range. Using this approach and a computer program the spectral reflectance curves, based on the shape of the spectral transmittance curves of the dye‐fiber polymer and Cauchy's dispersion formula, are calculated for an array of dyed nylon fibers. Also, the spectral reflectance curves for the same dyed fiber is calculated using Allen and Goldfinger model. Both spectra are compared with those experimentally measured. Spectra for dyed fibers with different dye concentrations are calcula

ISSN:0361-2317    

DOI:10.1002/col.5080170310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:0361-2317    

DOI:10.1002/col.5080170312

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY