The past couple weeks there has been a lot of glasses talk surrounding me. This got me thinking all about how our eyes work! I find it fascinating that Michael wakes up everyday and can see but I’m basically blind. Let’s take a better look, shall we? (Did you get my joke?? Lol)
The parts of the eye:
-Cornea: clear outer covering of the eye
-Iris: colored part of the eye surrounding the pupil that controls how much light enters the eye.
-Pupil: black dot in the center of the eye where light enters
-Sclera: white part of the eye
-Lens: Behind the pupil focusing light on the retina
-Retina: light sensitive lining in the back of the eye containing layers of cells that detect light and transform it into electrical impulses
We now know the parts of the eye! But how does it all work?? Let’s see (hahah another eye joke)
In the retina there are two cells known as photoreceptors that help to absorb light. They are known as rods and cones. Cones are in the center area of the retina and help us to see color. They also let us read and recognize details. Rods are on the outer area of the eye and allow us to see at night or in poor lighting.
Light reflects off whatever object we are looking at and the rays enter through the cornea at the front of the eye. The light continues to pass through and enters the pupil to reach the lens. The lens then changes in thickness to bend the light to focus on the retina at the back of the eye. On its way to the retina, the light continues through a thicker fluid that helps the eye maintain its round shape. When the light reaches the back of the eye and the retina, the light turns into electrical impulses that are carried to the brain from the optic nerve. The visual receptor of the brain interprets the impulse as what we see! And this all happens in milliseconds!! How crazy!!
For people who have glasses, this can be caused by the lens or even the shape of the eye! In both cases, you see blurry rather than focused. It is easily taken care of thanks to contacts or glasses. I am both nearsighted and farsighted meaning I can not see close or far! Farsightedness is due to an image focusing behind the retina while nearsightedness is due to images focusing in front of the retina.
It is so interesting how our eye shape and internal parts can control every part of what we see. Recently I purchased two pairs of glasses on www.zennioptical.com and I can not wait to share them when they come in with a full review!!
Til then,
Z
