An Eagle's Eye: Quality of the Retinal Image

@article{Shlaer1972AnEE,
  title={An Eagle's Eye: Quality of the Retinal Image},
  author={Robert Shlaer},
  journal={Science},
  year={1972},
  volume={176},
  pages={920 - 922}
}
  • R. Shlaer
  • Published 26 May 1972
  • Medicine
  • Science
The optical quality of a living eagle's eye was determined by an ophthalmoscopic method. The performance of the eye was substantially better than that reported for humans, but did not confirm some of the wilder claims made for such birds. 

Retinal image quality in the rodent eye

Using the measurements of the optics and the published behavioral and electrophysiological contrast sensitivity functions of rats, the CSF that the rat would have if it had perfect rather than poor optics is calculated.

Ocular Optical Filtering

The purpose of this chapter is to review the effects of optical filtering on eye function emphasizing such unresolved issues, for example, as the function of optical filters in the eyes of animals with high (suprahuman) visual acuity.

Falcon visual sensitivity to grating contrast

It is reported that the cut-off frequency (a measure of visual acuity) is twice the expected value and is the same for kestrel and human eyes.

The role of the limbal cornea in vision

The studies showed the eagle cornea to be thinner, scatter less light and be more spherical than the human cornea, and it is recommended that optical iridectomy be considered, in appropriate cases of corneal blindness with patches of clear peripheral cornea when no donorCorneal material is available.

An owl's eye: Schematic optics and visual performance inStrix aluco L.

  • G. Martin
  • Biology
    Journal of comparative physiology
  • 2004
The schematic eye ofrix aluco, a nocturnal owl species, is described and it is concluded that the essentially ‘nocturnal’ feature of the owl eye does not lie in either its light gathering power or the sensitivity of individual rod receptors.

Telephoto lens system of falconiform eyes

It is shown here that the presence of a spherical depression in the deep fovea of falconiforms may act like the negative lens component in a telephoto lens system or opera glass, thus providing the relatively large images necessary for more complete image reconstruction in a localised region of the retina.

The refractive development of the eye of the American kestrel (Falco sparverius): a new avian model

This study is the first indication that chickens may not be a representative bird model for studying form deprivation myopia, and kestrels are severely myopic at hatching and therefore, the direction of emmetropization is opposite to that found in hatchling chicks.

Fundamentals of spatial vision in the barn owl (Tyto alba pratincola) : ocular aberrations, grating acuity, contrast sensitivity, and vernier acuity

Optical quality in barn owl eyes is presented in terms of measuring the ocular wavefront aberrations with a standard Tscherning-type wavefront aberrometer under natural viewing conditions and the results suggest that image quality in Barn Owl eyes is excellent.

Avian mechanisms for vision in air and water

  • J. Sivak
  • Physics
    Trends in Neurosciences
  • 1980

Critical limiting factors in the design of the eye and visual cortex

Three stages of dealing with the visual image are proposed: the improvement of the cortical map in primary visual cortex by processes analogous to spatial and temporal interpolation; the detection of linking features in this map; and the concentration of this information by non-topographical mapping in adjacent visual areas.
...

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