To understand this issue in more detail, one needs to recall physics, namely, that light is a wave. The simplest example of this physical phenomenon is a rainbow appearing in the sky due to the fact that light is reflected in the smallest droplets of moisture in the air.

We also need to remember that our eyes see, in fact, not the objects themselves, but the light reflected from them. Due to the roughness of objects, part of the reflected rays is distorted, as a result of which their contours can be fuzzy. This is especially noticeable when a bright light strikes your eyes, making it difficult to consider surrounding objects.

Operating principle

Now let’s look at exactly how interference affects the clarity of objects when a person squints. A person narrows the muscles of the eyelids by adjusting the amount of light passing into him. A decrease in luminous flux leads to a reflex narrowing of the pupil. Eyelashes also help in the process, creating a shadow that weeds out excess rays. The eyelids act as an additional aperture, cutting off part of the distorted rays.

The field of view is narrowing. As a result, the image of the surrounding world, which is additionally focused using the lens, gets onto the retina (inverted).
In the fundus from the exact action of light, a more qualitative reaction of the finest nerve endings located in the retina of the fundus of the eye - “rods” and “cones”. The sticks are responsible for the perception of color, and cones for black and white perception.

By the way, the same process underlies photography. The brighter the light, the stronger you need to close the aperture to focus a brighter and sharper image.

It is worth paying attention: if a person begins to squint too often, this indicates that his vision begins to deteriorate. In this case, the person tries not to filter out the light, but to additionally act on the longitudinal and transverse muscles of the eye. They are responsible for ensuring that the eyeball is perfectly round. If for some reason the muscles began to work poorly, the eyeball is deformed. Century man is trying to return him to a normal position.