• intraocular
  • To determine the effectiveness of this foldable yellow-tinted intraocular lens (Yellow-IOL) in improving the quality of vision, we measured contrast sensitivity during the early postoperative period in eyes implanted with the Yellow-IOL or ordinary foldable intraocular lenses (UV-IOL). (arvojournals.org)
  • Refractive "vision correction" surgery (especially PRK with the complication of "haze") may rarely cause a reduction in best night-time acuity due to the impairment of contrast sensitivity function (CSF) which is induced by intraocular light-scatter resulting from surgical intervention in the natural structural integrity of the cornea. (wikipedia.org)
  • wavelength
  • It has been established that the maximum spectral sensitivity of the human eye under daylight conditions is at a wavelength of 555 nm, while at night the peak shifts to 507 nm. (wikipedia.org)
  • In sensor systems, where the output is easily quantified, the responsivity can be extended to be wavelength dependent, incorporating the spectral sensitivity. (wikipedia.org)
  • In other contexts, the spectral sensitivity is expressed as the relative response per light energy, rather than per quantum, normalized to a peak value of 1, and a quantum efficiency is used to calibrate the sensitivity at that peak wavelength. (wikipedia.org)
  • binocular
  • In the binocular measurements at2.5% contrast, sensitivity decreased in 49% of the core makers and 21% of the controls (P=0.002). (ebscohost.com)
  • A practical measure of binocularity is the binocular summation ratio BSR, which is the ratio of binocular contrast sensitivity to the contrast sensitivity of the better eye. (wikipedia.org)
  • Schrödinger (1926) put forth an equation for binocular brightness and contrast combination where each monocular input is weighted by the ratio of the signal strength from that eye to the sum of the signal from both eyes. (wikipedia.org)
  • scotopic
  • Scotopic vision Mesopic vision Candela Purkinje effect Photometry Photosensitive ganglion cell Adaptation (eye) Contrast (vision) Cone cell Pelz, J. (1993). (wikipedia.org)
  • color vision
  • In spite of these complexities, however, the conversion of light energy spectra to the effective stimulus, the excitation of the photopigment, is quite linear, and linear characterizations such as spectral sensitivity are therefore quite useful in describing many properties of color vision. (wikipedia.org)
  • describe
  • In visual neuroscience, spectral sensitivity is used to describe the different characteristics of the photopigments in the rod cells and cone cells in the retina of the eye. (wikipedia.org)
  • In photography, film and sensors are often described in terms of their spectral sensitivity, to supplement their characteristic curves that describe their responsivity. (wikipedia.org)
  • movements
  • This study estimates contrast sensitivity and spatial resolution of two species of benthic sharks, the Port Jackson shark, Heterodontus portusjacksoni , and the brown-banded bamboo shark, Chiloscyllium punctatum, by recording eye movements in response to optokinetic stimuli. (biologists.org)
  • Eye movements ceased at 0.38 cycles per degree, even for high contrasts, suggesting low spatial resolution. (biologists.org)
  • Results
  • In dry eye, reduced contrast sensitivity in part results from central SPK overlying the optical zone and the increased straylight results from tear film instability rather than central SPK. (arvojournals.org)
  • conditions
  • The most important variables, in addition to size, that determine visibility under these conditions are the contrast of the target against a background, and whether it is moving or flickering on and off. (druglibrary.org)
  • Under normal conditions, contrast sensitivity in Yellow-IOL group is better than that of UV-IOL group at all frequency regions. (arvojournals.org)
  • Under glare conditions, contrast sensitivity at the low frequency region was lower than that under normal conditions in both UV-IOL and Yellow-IOL groups. (arvojournals.org)
  • However
  • However, there are several techniques that permit not only the evaluation of contrast sensitivity, but also allow researchers to obtain a more complete description of the overall functioning of the visual system (Campbell & Green, 1965). (druglibrary.org)
  • The responses of the rod and cone cells of the retina, however, have a very context-dependent (coupled) nonlinear response, which complicates the analysis of their spectral sensitivities from experimental data. (wikipedia.org)
  • reduction
  • This is how a reduction of contrast can reduce the clarity of an image - by removing its fine details. (wikipedia.org)
  • A major drawback to application of the algorithm is an inherent reduction in overall image contrast produced by the operation. (wikipedia.org)
  • study
  • The present study aimed to compare the diagnostic value of contrast-enhanced magnetic resonance angiography (CE MRA) with 3D time-resolved imaging of contrast kinetics, color Doppler ultrasound (CDUS) and digital subtraction angiography (DSA) in extracranial carotid stenosis (CS). (readbyqxmd.com)