Site for children

J. Perelman
"Entertaining physics". Book 1.
Chapter 9. Vision one and two eyes


Nearsighted without glasses sees bad; but what he sees and what seemed to him the subject is about people with normal vision have a very vague idea. Meanwhile, short-sighted people quite a lot, and it is useful to see how you draw the world around them.

First of all, short-sighted (of course, without glasses) never sees sharp contours: all items for him are vague outlines. People with normal vision, looking at the tree, distinguish between individual leaves and twigs, clearly looming against the sky. Myopic sees only a shapeless green mass of obscure, fantastic shapes; small parts to get lost.

For nearsighted people human faces seem in General younger and more attractive than a person with normal eyesight, wrinkles and other minor defects of the face by them unnoticed; rough-red leather (natural or artificial) seems pale rosy. We are amazed at the naivety of other acquaintances, failed almost 20 years to determine the age of people marvel at their strange taste in assessing shop, blame them disrespectful, when they look us straight in the face and did not seem to want to know... All this often happens just from myopia.

“In high school, " recalls the poet Delvig, contemporary and friend of Pushkin, " I was forbidden to wear glasses, but all the women seemed fine; I was disappointed after the release!”. When short-sighted (without glasses) talks with you, he doesn't see your face - in any case, sees not what you expect: before him a vague way, and it is not surprising that, having met you for the second time in an hour, he already knows you. For the most part short-sighted recognize people not so much in appearance as the sound of voices: the lack of vision is filled by the sophistication of the hearing.

It is also interesting to see that what is drawn nearsighted people, the world at night. At night all bright objects - lamps, lamp, lighted Windows, etc. - grow for myopic huge, turning a painting into a formless chaos of bright spots, dark and foggy silhouettes. Instead of lines of lights on the street nearsighted see two or three huge bright spots which cover for them the rest of the street. The approaching car, they do not distinguish, instead they see only two bright halo (lights), and behind them a dark mass.

Even the night sky is for short-sighted not the kind that normal eyes. Myopic sees only stars of the first three or four values; therefore, instead of a few thousand stars are available to only a few hundred. But these few stars seem to him a large clods of the world. The moon seems short-sighted very close; the Crescent accepts for his intricate, fantastic form.

The cause of all these distortions and the apparent increase in the size of the objects is, of course, your eye is nearsighted. The myopic eye is too deep - so much so that the refraction of its parts collects rays of external objects not on the retina, and a few ahead of her. The retina, covering the fundus of the eye, reach the beams of rays, which give here a vague, blurry images.

Entertaining physics J. Perelman


System Orphus


Did you like our site and you would like to support it? It's very simple: tell your friends about us!

  © 2014 All children