The eye has several surprising optical properties: although it is an extremely wide angle (almost 180 degrees) system, no vignetting is noticed. This is due to the peripheral image being closer to the principal point, thus producing a smaller and brighter image to compensate for the reduced pupil area. Also, The central image does not have a small image as the image is focussed behind the retina, hyperopia of normal eye. The cone shape tends to defocus any light not absorbed by the visual pigment outside of the fovea. The dark adaptation of the rods and cones is more similar than is given in standard references on the subject. The significance of these properties is discussed in relation to retinal injury levels and flash blindness from laser exposures.

1.
Bengi
,
H.
, and
Thomas
,
J. G.
Studies on human ocular tremor, pp
281
292
. In:
Perspectives in Biomedical Engineering
(ed. by
Kenedi
R. M.
)
MacMillan
,
London
,
1973
.
2.
Ditchbum
,
R_ W
.
Eye Movement and Visual Perception
.
Oxford
:
Oxford University Press
,
1973
.
3.
Glickstein
,
M
. and
Millodot
,
M
. (
1970
).
Retinoscopy and Eye Size, Science
,
168
,
605
606
.
4.
Green
,
D.G.
,
Powers
,
M.K.
, and
Banks
,
M.S
.
Depth of Focus, Eye Size, and Visual Acuity, Vision Res.
,
20
:
830
,
827
835
,
1980
.
5.
Gubisch
,
R. W
.
Optical performance of the human eye
.
J. Opt. Soc. Am
.
57
,
407
415
,
1967
.
6.
Helmholtz
,
H. v
.
Treatise on Physiological Optics
.
3
vol., (Ed. by
Southall
J. P. C.
)
New York
:
Optical Society of America
,
1924
.
7.
Kolb
,
H
.
The organization of the outer plexiform layer in the retina of the cat: Electron microscopic observations
.
J. Neurocytol
,
6
,
131
153
,
1977
.
8.
Le Grand
,
Y.
Form and Space Vision
. (Translated by Millodot M., and Heath G. G.).
Bloomington
:
Indiana University Press
,
1967
.
9.
Polyak
,
S
.
The Retina
.
University of Chicago Press
,
Chicago, IL
.
1941
.
10.
Ringo
,
J.
,
Wolbarsht
M. L.
,
Wagner
,
H. G.
,
Crocker
,
R.
and
Amthor
,
F
.
Trichromatic Vision in the Cat
.
Science
,
198
,
753
754
,
1977
.
11.
Sliney
,
D. H.
and
Wolbarsht
,
M. L
.
Safety With Lasers and Other Optical Sources
.
1035
pp.,
Plenum Press
,
New York
,
1980
.
12.
Snyder
,
A. W.
, and
Miller
,
W. H
.
Photoreceptor diameter and spacing for highest resolving power
.
J. Opt Soc. Am
.
67
,
696
698
,
1977
.
13.
Van Buskirk
,
C.
,
Wolbarsht
,
M. L.
, and
Stecher
,
K.
, Jr
.
The nonnervous causes of normal physiologic tremor
.
Neurology
161
,
217
220
,
1966
.
14.
Westheimer
,
G
.
Spatial frequency and light spread descriptions of visual acuity and hyperacuity
.
J. Opt. Soc. Am
.
67
,
207
212
,
1977
.
15.
Wolbarsht
M. L
.
Movement of Optical Displays in Relation to the Retinal Mechanisms for Visual Acuity
. Report No. NADC-85035-60,
Naval Air Development Center
,
Warminster, PA
18974, 25 March
1985
.
16.
Wolbarsht
M.L.
,
Fulton
,
A.B.
, and
Wagner
,
H.G
.
Small Eye Hyperopia is Not an Artifact Invest
.
Ophthal. Vis. Sci.
,
26
(
3
)Suppl., 142,
1985
.
17.
Wolbarsht
M. L.
,
Wagner
,
H. G.
and
Ringo
,
J. R.
Retinal Mechanisms for Improving Visual Acuity, pp.
167
187
. In:
The Visual System
(
Fein
A.
and
Levine
J.S.
, eds.), MBL (Marine Biological Laboratories) Lectures 5,
Alan R. Liss
,
New York
,
1985
.
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