Page 44 - Miracle in the Eye

MIRACLE IN THE EYE

Naturally, neither the lens nor the cells comprising it have any will of their
own. The lens, cornea, iris, retina, their cells and the muscles around them, and
the brain all carry out their functions in ways inspired by God, and by His will.

The Retina

The retina receives the beams of light refracted by the cornea and the lens,
and constructs the image we see. This image is then sent to the brain in the form
of electrical signals (Figure 1.15).
The retina serves exactly the same purpose for the eye as the film does for
a camera. In the same way that photographic film lies behind the lens, the retina
lies at the back of the eyeball and there forms an image of the object being fo-
cused on.
Once a camera has recorded an image, the film is moved onto the next un-
exposed empty frame space so that another photograph may be captured. The
retina, on the other hand, receives countless images every second, but doesn't
have to change or be replaced, because the retina is capable of renewing itself. It
displays and uses countless images throughout an entire lifetime without dete-
riorating or breaking down.
The retina is composed of eleven separate, microscopically thin layers
(Figures 1.16 and 1.17). Images fall on the ninth layer, an area almost 1 millime-
ter wide. It's quite amazing to consider that entire kilometers of landscape can
be focused down upon this tiny point. No one should forget that his whole
world is recreated within this tiny area; that thanks to that area, he has per-
ceived the existence of everything he has ever seen; and that ultimately, that
point is nothing more than a tiny concave layer of cells.
At the back of the retina are a number of rod-shaped and cone-shaped
cells. These cells convert received light into electrical signals. Because of their
shape as observed under a microscope, they are called rods and cones. There are
6,000,000 cones and 120,000,000 rods; a ratio of nearly 20 rods to every cone.
But the only difference between these two cells is not their shape or their
number. Each type of cell has a different method of perception. Rods can re-
spond to even the weakest beams of light. For the cones to respond, however,
more powerful light is needed.

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