Results 261 to 270 of about 2,322,259 (309)
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Science, 1976
Grating acuity, the ability to resolve high-contrast square-wave gratings, was measured in a falcon and in humans under comparable conditions. This behavioral test of falcon acuity supports the common belief that Falconiformes have superb vision—the falcon's threshold was 160 cycles per degree, while the human thresholds were 60 cycles per degree ...
R, Fox, S W, Lehmkuhle, D H, Westendorf
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Grating acuity, the ability to resolve high-contrast square-wave gratings, was measured in a falcon and in humans under comparable conditions. This behavioral test of falcon acuity supports the common belief that Falconiformes have superb vision—the falcon's threshold was 160 cycles per degree, while the human thresholds were 60 cycles per degree ...
R, Fox, S W, Lehmkuhle, D H, Westendorf
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Vision Research, 1967
Abstract Rabbits were trained to discriminate vertical and horizontal striations. By changing the width of the white and black bars, visual acuity was studied. Four animals were studied. In three of them the finest pattern that could be discriminated was that in which the bars were seen under a 20′ visual angle.
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Abstract Rabbits were trained to discriminate vertical and horizontal striations. By changing the width of the white and black bars, visual acuity was studied. Four animals were studied. In three of them the finest pattern that could be discriminated was that in which the bars were seen under a 20′ visual angle.
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Nature, 1947
MOST published researches on visual acuity have assumed an unrestricted time of observation, but recent studies of the relations between intensity discrimination and acuity, and photo-chemical theories thereof, have indicated that the wandering of fixation plays an important part in the performance of the visual system.
L C, MARTIN, W, KANIOWSKI
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MOST published researches on visual acuity have assumed an unrestricted time of observation, but recent studies of the relations between intensity discrimination and acuity, and photo-chemical theories thereof, have indicated that the wandering of fixation plays an important part in the performance of the visual system.
L C, MARTIN, W, KANIOWSKI
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Reproducibility of Visual Acuity Assessment in Normal and Low Visual Acuity
Strabismus, 2007To assess the reproducibility of measurements of visual acuity in both the upper and lower range of visual acuity.The retroilluminated ETDRS 1 and ETDRS 2 charts (Precision Vision) were used for measurement of visual acuity. Both charts use the same letters. The sequence of the charts followed a pseudorandomized protocol. The examination distance was 4.
Ralph, Becker +2 more
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Visual acuity is the simplest and most utilized assessment of visual function. Reductions in acuity may result from many causes, including diseases of the macula and associated visual pathways and optical blur. Chart design and the psychophysical procedures employed to determine visual acuity impact measurement reliability and validity.
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Visual acuity in children with dyrocephalus
Clinical Neurology and Neurosurgery, 1997Several studies have described impairment of visual function in children with hydrocephalus. Decreased visual acuity in hydrocephalic children can be due to either ophthalmological defects or defective function of the cerebral part of the visual pathways. In the latter case, the term cerebral visual impairment (CVI) is used.
Oud, K.T. +4 more
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Annual Review of Entomology, 1997
▪ Abstract The acuity of compound eyes is determined by interommatidial angles, optical quality, and rhabdom dimensions. It is also affected by light levels and speed of movement. In insects, interommatidial angles vary from tens of degrees in Apterygota, to as little as 0.24° in dragonflies.
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▪ Abstract The acuity of compound eyes is determined by interommatidial angles, optical quality, and rhabdom dimensions. It is also affected by light levels and speed of movement. In insects, interommatidial angles vary from tens of degrees in Apterygota, to as little as 0.24° in dragonflies.
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2014
The Enhancing Visual Acuity (EVA) System (Dutch Ophthalmic Research Centre International B.V.) features a unique fluid control system - VacuFlow Valve Timing Intelligence (VTi®) - and represents the next-generation evolution of pump machines. VacuFlow VTi® overcomes the limitations of existing Venturi and peristaltic pumps and provides the potential to
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The Enhancing Visual Acuity (EVA) System (Dutch Ophthalmic Research Centre International B.V.) features a unique fluid control system - VacuFlow Valve Timing Intelligence (VTi®) - and represents the next-generation evolution of pump machines. VacuFlow VTi® overcomes the limitations of existing Venturi and peristaltic pumps and provides the potential to
openaire +2 more sources