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Smith V C - - 1978
We examined a 19-year-old woman with acute posterior multifocal placoid pigment epitheliopathy one week after she noted blurring of central vision. Her corrected visual acuity was R.E.: 6/7.5 (20/25), and L.E.: 6/12 (20/40). The visual fields showed 10-degree pericentral scotomas. A color vision defect and an abnormal Stiles-Crawford effect were ...
Smith V C - - 1978
A unique form of dichromatic color vision is described in a family with incomplete achromatopsia. In 1966, incomplete achromatopsia was diagnosed in 4 of 14 children of a consanguineous marriage. The 4 affected had best visual acuities of 6/60 or 6/180, pendular nystagmus, and aversion to bright lights. The ERG ...
Albee J L - - 1977
Fading and regeneration of visual stimuli is a phenomenon which occurs under the condition of redundant visual stimulation in the human eye. By totally encompassing a subject's visual field with large sheets of colored cardboard, which provided an undifferentiated ground, it was found that the color spontaneously disappeared and reappeared. ...
Little A C - - 1977
The purpose of this study is to investigate an earlier finding wherein more than 100 subjects in four age groups responded systematically but differently to Munsell hues. According to the theoretical construction of the Munsell Color System, the spacing of the 10 hues is in perceptually equal intervals; the error ...
Valberg A - - 1977
Tansley and Boynton have recently demonstrated that color stimuli whose chromaticities all fall on a particular triptanopic confusion line in the CIE (x,y) diagram do not form distinct borders with each other. A tritanopic purity-difference function, involving only r- and g-cone contributions, is demonstrated to provide (i) a prediction of ...
Nathanson D E - - 1977
Moderately and severely retarded adolescents (N=70) individually viewed a cartoon, a live action film, and a pixilation film in color or black and white. A distractor method was used to measure frequency and duration of eye movement to visual stimuli. Content of visual stimuli was controlled, presentation of a distractor ...
Breneman E J - - 1977
Two similar complex targets, consisting of neutral patches ranging from white to black, were viewed, one in a dark surround and the other in an extended illuminated surround of 20% reflectance. Each target was viewed from a distance of three times its width, which is typical of picture viewing. The ...
Raymond L A - - 1977
Benjamin Franklin may share a prominent place in the history of photocoagulation. He devised an uncomplicated experiment showing the effect of color on the absorption of light by solids and its conversion into heat motion of the molecules. His experiment and the related experiments of others leading ultimately to the ...
Baugh R - - 1977
The degradation of phenylbutazone was studied in the presence of lakes suitable for coloring the sugar coats of phenylbutazone tablets. The drug was degraded, in light, in the presence of erythrosine sodium. The degradation probably proceeds via singlet oxygen generated by the light-exicited dye. The degradation may be important in ...
Chen S M - - 1977
Alleles at the C locus in maize include C, one of the complementary genes required for anthocyanin pigmentation in the aleurone tissue of the mature kernel; C-I, dominant inhibitor of pigmentation; and c, recessive colorless. The recessive colorless alleles can be differentiated into two distinct forms: c-p (p for positive), ...
Sparrow J G - - 1977
A ten-color Fabry photometer was used during Skylab missions SL-2 and SL-3 to measure sky brightness and polarization associated with zodiacal light, background starlight, F region airglow, and spacecraft corona. A brief description is given of the design, calibration, and performance of the instrument.
Poulton E C - - 1977
Altogether 168 men searched briefly for colored sloping lines embedded in a background of random color. Using a separate-groups experimental design, search for six kinds of target was found to be less effective after practice than search for a single kind of target. Reducing the number of colors of targets ...
Horne E P - - 1977
The estimation of number depends on the information as dot frequency, exposure conditions, order of presentation, and sensitivity of the observer to color. Ninety-six color-normal observers (age 17-27) equally divided by sex were assigned so that each one viewed 42 cards, each of which contained dots of one of three ...
Carlow T J - - 1976
Seven subjects were studied to determine the reproducibility of color isopters utilizing a Tubingen perimeter with targets equated for radiant energy and separate for heterochromatic flicker luminance. Achromatic threshold recognition of targets for equal luminance gave smaller isopters with longer wavelengths (red). Color recognition thresholds, on the other hand, showed ...
King-Smith P E - - 1976
An acquired unilateral color defect in a 22-year-old man has been investigated with standard clinical tests and by using techniques which, it is thought, test specifically for the sensitivity of the luminance and opponent-color systems. The spectral sensitivity of the defective left eye, using 1 degree 200 ms. test flashes ...
King-Smith P E - - 1976
We show how the processes of visual detection and of temporal and spatial summation may be analyzed in terms of parallel luminance (achromatic) and opponent-color systems; a test flash is detected if it exceeds the threshold of either system. The spectral sensitivity of the luminance system may be determined by ...
Delori F C - - 1976
Pure colored light in a narrow spectral band improves ophthalmoscopy and photography of the human ocular fundus. The contrast of fundus details is enhanced and the loss of quality of the image associated with chromatic aberrations is eliminated. The monochromatic technique also improves the localization of structures in the stratified ...
Sharpe L T - - 1976
The effect of dividing-strip width (sample proximity) upon sensitivity to suprathreshold and threshold color differences is explored by three methods that involve ratio comparisons, liminal determinations, and repeated color matchings. The results suggest, in general, that sample separation impairs lightness discrimination more than chromaticness discrimination and that it may be ...
Götz K O - - 1975
Color preferences of 190 art students (Götz & Götz, 1974, 1975) were compared with the corresponding scores on extraversion (E) and neuroticism (N). It was found that the preferences of a group of 27 highly gifted young artists were different from preferences of average and less gifted Ss who had ...
Markle A - - 1975
Recent research had demonstrated that dark-eyed individuals are more reactive than light-eyed people. The present paper investigated one area of reactivity, ease of emotional arousal. The hypothesis that dark-eyed male subjects (n equals 40) would show greater ease of arousal than light-eyed male subjects (n equals 40) was tested using ...
Gedzelman S D - - 1975
A theory for the color of the sky near the horizon for an observer in the umbral region of a total solar eclipse is presented. The model uses a Rayleigh scattering atmosphere, and the light reaching the observer is a beam of singly scattered sunlight, which, in turn, has suffered ...
Coleman D J - - 1975
This report describes a system that allows amplitude information to be used as a third dimension or aspect of display on B-scan ultrasonograms. The relative strength of reflected echoes can be shown on B-scan by means of gray scale, color coding, or on A-scan with amplitude deflection. With this new ...
- - 1975
[This corrects the article on p. 206 in vol. 30.].
Fischer G J - - 1975
Four experiments assessed the effects of stimulating chick embryos with colored light at 2 intensity levels. Both posthatch color pecking preferences (Experiments 1 and 2) and color discrimination learning (Experiments 3 and 4) were unaffected. These results affirm and extend a prior finding of no pre- and posthatch colored light ...
Phillips R A - - 1975
Experiments were carried out to provide an empirical basis for setting color standards for sunglasses. Nineteen individuals, ten with anomalous color vision, viewed traffic signals through a series of color filters. Limits on the apparent color shift for the amber and green signals as well as for D65 are presented ...
Hanson H M - - 1975
Toxic effects on sensory systems have rarely been evaluated by psychophysical methods. As examples of possible applications four studies are described. Sodium salicylate and kanamycin, both reported to produce hearing deficits in man, have also been demonstrated to affect auditory thresholds in monkeys. With the latter drug the deficits measured ...
Mueller H C - - 1975
Hawks were offered one color of mouse for ten consecutive captures and then a choice between that and another color. The birds usually selected the odd, or unusual, color. This behavior is probably adaptive because odd prey in nature would be unfit.
Berman M S - - 1975
Six hysterical amblyopes and six controls, matched for age and sex, were evaluated as to acuity, color vision, visual fields, dark adaptometry and visual evoked responses (VER). Although the hysterical amblyopes all showed reduced acuity and constricted visual fields, no statistically significant differences were found for the dark adaptation final ...
Dwyer W O - - 1975
The present experiment investigated the possibility that variation in fundus pigmentation among individuals may be related to differential color sensitivity. Fifty black and white observers representing a wide range of skin (and fundus) pigmentation made direct heterochromatic brightness matches for a white standard field against each of five chromatic comparison ...
Wallace B - - 1975
The number of reported changes in direction of autokinetic movement was assessed as a function of color of the light that served as stimulus, viewing angle (0, 30, or 60 deg of displacement from straight ahead), and dark adaptation. Color and dark adaptation had no significant main effect on the ...
Kolers P A - - 1975
When disparate shapes are flashed under the appropriate temporal and spatial conditions, the human visual system resolves their disparity smoothly and continuously. No equivalent supplementations are found for color, which the system resolves by abrupt transformation. Shape and color reveal themselves, contrary to some modern theorizing, as properties handled in ...
Labrunie G - - 1974
We report the principle of a new type of digital light deflector utilizing the electrooptic effect of index modulation in nematic liquid crystals and the results of the optical tests that were performed on this device. Optical efficiencies and contrasts, electrical operating conditions, and subsequent turnon times are given. A ...
Farthing G W - - 1974
In Experiment I, pigeons were first trained on simultaneous matching-to-sample with either color stimuli or form stimuli, and then shifted to stimuli on the other dimension. Matching performance in the first session with stimuli on a given dimension was not affected by prior matching training with stimuli on the other ...
Noguchi M - - 1973
Multicolor holograms for white-light reconstruction are recorded using four primary wavelengths of a krypton ion laser and a helium-neon laser. On the basis of colorimetry performed with the aid of a color computer, the colors observed with the eye through the holograms, as well as those of original transparencies (color ...
Maki W S WS - - 1973
Two pigeons performed a three-key matching-to-sample task. The comparison (side key) stimuli were either solid colors or white lines. The sample (center key) stimuli were either compounds (white lines on colored grounds) or elements (white lines on black grounds on some trials, and solid colors on other trials). Sample stimuli ...
Wooten B R - - 1973
It is possible that so-called normal trichromatic vision occurs only between the central blue-blind fixation area and about 30 degrees peripherally. Beyond about 30 degrees vision has been alleged to become dichromatic (red-green blind), and beyond about 60 degrees , monochromatic. Hence every form of color blindness may characterize various ...
Halpert H - - 1972
N-color (Hg,Cd)Te photodetectors capable of spectral band analysis have been fabricated, tested, and delivered. This paper discusses the state of the art in (Hg,Cd)Te n-color photoconductive detectors. Included is a discussion of narrow band two-color devices responsive in the region of 8-14 micro. D*lambda (lambda(p), 10 kHz, 1) higher than ...
Witzel R F - - 1972
The results of a brief experiment are described in which the perception of certain color intervals is compared with their corresponding intervals as computed from MacAdam's geodesic chromaticity diagram, the Munsell renotation system, using the Godlove formula and the 1964 CIE color-difference formula.
Matsuda S - - 1972
This paper is concerned with flare measurement in photographic lenses by three colors instead of white light. The results have interesting relations to the antireflection coating, the barrel interior finishing, area and condition of the iris diaphragm of the lens, and the lens edge painting. For color photography, it is ...
Thornton W A - - 1972
Evaluation of color-rendering capability of commercial lamps is considered from the point of view of the lampmaker and the typical user, rather than for precision color-matching applications. Only an approximate magnitude of color-rendering capability of a test lamp has meaning for the average user. Only illuminants of superb color-rendering capability ...
Favreau O E - - 1972
When observers who watched repeated alternations of a red contracting spiral and green expanding spiral were later shown stationary spirals, red and a green the red stationary spiral appeared to be expanding and the green stationary spiral appeared to be contracting. These color-contingent motion after effects complement reports of motion-contingent ...
Macovski A - - 1972
Color information is recorded on a colorless substrate by having each color separation amplitude modulate a different spatial frequency carrier. This is accomplished in a single exposure using an appropriate color-encoding filter. The reconstruction of the color scene involves a point source projector with a color decoding mask. The light ...
Ohta N - - 1971
Color matching today is based upon the metamerism principle which necessitates agreement of only a trichromatic specification. The amounts of a set of three dyes (e.g., cyan, magenta, and yellow) to reach a certain chromaticity and lightness (u,v,Y) is decided uniquely when the spectral density distributions of the dyes are ...
Velasquez D A - - 1971
This paper reports observations of the zenith sky brightness around totality at 5580 A and 6300 A during the eclipse of 12 November 1966. The observations were carried out at Santa Ines, Huancavelica, Peru, using interference filter photometers. The color change and the variation of the sky brightness at zenith ...
Faulhaber M E - - 1971
This paper describes a new instrument, based on the cube-root system of color coordinates, which reads color-difference coordinates directly. Silicon photovoltaic cells are used with glass filters to produce electrical signals proportional to tristimulus values. Tristimulus signals from a reference and a sample are converted to coordinate differences by means ...
Wright A A - - 1971
Six pigeons were trained to match wavelengths in a three-key matching-to-sample paradigm. Test trials were occasionally presented, where probe wavelengths appeared on the center key and choices were made to the training stimuli presented on the side keys. Color naming functions were obtained by plotting the percentage of test trials ...
Valberg A - - 1971
Based on the optical principle of a slide projector, a visual tristimulus projection colorimeter has been developed. The calorimeter operates with easily interchangeable sets of primary color filters placed in a frame at the objective. The apparatus has proved to be fairly accurate. The reproduction of the color matches as ...
Helson H - - 1970
Effects of spectral energy distributions of sources and colors of backgrounds on the pleasantness of object colors were determined by having 5 men and 5 women rate 125 object colors on 25 colored backgrounds in 5 sources of illumination. In addition, foods and complexions were rated in the same sources. ...
Ehrman L - - 1970
The mating advantage of rare Drosophila males in tested using two eye color mutants. In one experiment, the flies remained for three hours in observation chambers containing 25 pairs; in another experiment they stayed for 24 hours in mass cultures of 200 individuals. The outcome of this latter experiment was ...
Hoover R B - - 1969
The painstaking labors of a professor in Speyer, Germany, produced a most remarkable work on Fraunhofer diffraction over a century ago. Die Beugungserscheinungen by F. M. Schwerd (published in Mannheim in 1835) was profusely illustrated with excellent drawings of the calculated amplitude and intensity distributions of the Fraunhofer patterns of ...
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