The Eye as a Camera

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The Eye as a Camera

• Michael A. Sandberg, Ph.D.
• Associate Professor of Ophthalmology
• Berman-Gund Laboratory for the Study of Retinal
  Degenerations
• Harvard Medical School
• Massachusetts Eye and Ear Infirmary

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Principal parts of the camera

• The lens and filters
• Cornea
• Lens
• Macular pigment
• The aperture
• Pupil
• The shutter
• Retina
• The film
• Retina

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Schematic eye
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Optical power of the human eye

• Cornea 43 diopters
• Lens (eye focused at infinity) 20 diopters
• Lens (eye focused at near) 28 diopters

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Monocular visual field
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Visual angle of common objects

• Sun or moon 0.5
• Thumbnail (at arms length) 1.5
• Fist (at arms length) 8 - 10

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Optical aberrations

• Spherical aberration lt 0.5 diopter
• Chromatic aberration 2 diopters

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Distribution of macular pigment
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Range of Vision
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Critical duration
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Critical flicker frequency
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Visual acuity versus pupil size
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Normal Fundus
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The Human Retina
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Schematic retina
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Foveal architecture
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In vivo microscopy
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Photoreceptor structure
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Photoreceptor architecture
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Directional sensitivity
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Photoreceptor architecture
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Rhodopsin localization
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Rhodopsin regeneration
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Cone pigment regeneration
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Dark adaptation
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Effect of bleaching on threshold
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Rod and cone spectra
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Luminous efficiency curves
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Spectral sensitivity curves
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Number of photoreceptors in the human retina
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Photoreceptor distribution
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Photoreceptor mosaic
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Foveal cone mosaic
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Visual acuity versus eccentricity
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Visual acuity versus luminance