Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
HOW DOES THE EYE WORK?
Transcript of HOW DOES THE EYE WORK?
There are many parts that go into the eye allowing us to see and do the things we take for granted.
In order for the eye to allow us to see, it must adjust our "light levels".
Babies see upside-down and as they grow their brain will then start to flip the image
There is a rare condition that few people have that makes you see upside down, your mind does not change the image.
Each of your eyes has a small blind spot in the back of the retina where the optic nerve attaches. You don’t notice the hole in your vision because your eyes work together to fill in each other’s blind spot.
HOW DOES THE EYE WORK?
Basic Parts of the Eye
This is a quick song that will explain the parts of the eye
Work Cited-- Websites Used
Light enters the eye through the cornea and pupil.
The pupil is very sensitive and will change sizes in order to adjust to the amount of light there is in a the room.
Lots of light - pupil gets smaller
Minimal light- pupil gets larger
Video on light entering eye
The lens is seen after the pupil, and like everything else helps in the process of creating a clear sharp image to apear on the retina.
To do this:
The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina.
In order to change shape the Ciliary Muscles that surrounds the lens will relax and tense up.
This adjustment of the lens is known as accommodation. The accommodation reflex is a reflex action of the eye, in response to focusing on a near object, then looking at distant object (and vice versa). Accommodation is similar to the focusing of a photographic camera via movement of its lenses.
Our eye doesn't just look at an object and immediatly see it. In fact, your eye will initially see the the object upside down, and it is your brain that will thinks it's upright.
Some points we will metion are:
The innermost of the three tissue layers that make up the eye
It is embedded with millions of light sensitive cells:
used for vision in poor light
used for sharp central vision and detail; are packed behind the retina in the fovea
***The retina is important because its job is to recieve light that is focused by the lens, convert it to neural (brain) signals, and send it to the brain for visual recognition***
In order to see, we must have light.
Depending on the substance, the light ray we see can either be:
When the light finally enters the eye however, it is only either
. This refraction occurs after light travels through the cornea.
*Play until 1:36*
- the clear front surface of the eye that acts like a protector. (Alike to a camera lens)
The Iris & Pupil
- the Iris controls the light that enters your eye by adjusting the size of the pupil, the hole that goes all the way into the back of your mind.
- located directly behind the pupil and helps to further focus light. The lens helps the eye automatically focus on near and approaching objects, like an autofocus camera lens.
- the light-sensitive inner lining of the back of the eye. The retina converts optical images into electronic signals.
The Optic Nerve
- transmits the electronic signals to the visual cortex — the part of the brain that controls our sense of sight. (by now your mind will have converted the upside-down image to what we really see day to day)
Bent Light Ray
Refraction Light Ray
When the Retina receives the image from the outside world, the image will not only be upside-down, but also split in half and distorted. Each half of your brain will receive one half of the image, and then scramble the images together to compose the whole picture we are use to seeing.
Video On Lens
Sarah Leonard; Thomas Barish; Nolan Clark