The Science Behind Vision - Understanding Why You Might Have to Buy Eye Glasses in Langley One Day
Your parents might have glasses, or no one in your family needs them. So, when the eye doctor tells you that you need eye glasses, you might wonder what makes you so unique. The human eye is a remarkable structure full of intricacies and complexities. In many ways, it compares well to a camera, using a lens that allows light to enter, focus, and then features a light-sensitive membrane in the back.
To truly understand why you might need glasses one day, you first need to fully comprehend what gives your eyes the ability to see.
Exploring the Details of Vision: How Does the Eye Work?
When you consider how your eye works, some questions might come to mind, such as how does your brain interpret what you see? What makes you see colours and why do some people have difficulty perceiving the same colours? Lastly, you might wonder what makes you see in three-dimensions rather than everything appearing like a flat object in front of you.
Here are some key facts to know about how your eyes work and see the world around you:
• What controls the light entering the eye? The amount of light you have penetrating is controlled by your iris – more specifically the radial and circular muscles of it. These contract and relax, altering the pupil’s size. First, light passes through your cornea, then moves on toward the lens, which bends the light and focuses it to the retina in the back of your eye.
• What is a retina? Your retina consists of cones and rods that are light-sensitive. The receptors in the retina change as light strikes them, which sends an electrical message to the brain through your eye’s optic nerve – the connecting path between your eye and your brain.
• What happens at the back of the eye? At the back of your eye, the light-sensitive cells trigger signals when light strikes them. These signals then go through multiple connections before transferring from the eye to the brain. The path they take includes going from the interneurones to neurones (also known as ganglion cells). The cells then filter out some of the information they receive, which helps them decipher contrast and definition before sending it over to the brain.
• How does each optic nerve work? You have an optic nerve for each eye, and they cross over, then come together at the optic chiasm. Signals from the left side of both eyes then transfer to your left brain, while signals from your right-side transfer to the right, which combines the images.
• How does your brain see what comes from the eyes? The signals sent along the optic nerve enter via the thalamus. The thalamus then takes the information and separates it into colour and detail, and the other half involves contrast and movement. The messages then distribute into the visual cortex of the brain and reconstruct the image.
• How does the brain interpret colour? While colours surround you, you only detect three wavelengths of light in your eye, which include green, blue, and red. By combining these colours within the brain, you see other shades too. Your eyes come with over 7 million cone cells, each with three proteins sensitive to colours. When photons hit those colour-sensitive proteins, they will change shape, and trigger electrical messages to the brain. Half of your cone cells respond to red, a third will respond to green, and only about 2 percent respond to blue.
The Science is Fascinating, but So are the Eye Glasses that Help You See Even Better
While the science behind your vision is amazing – and sometimes hard to believe – it is essential that you use your vision’s full potential. If you notice squinting when you try to read near or far, it might be time for a quick eye exam and possibly being fitted for eye glasses.
The team at Langley Optometry can help find the stylish pair of eye glasses you need to explore the world the way science intended.
Find your eye glasses here at Langley Optometry or schedule an eye exam. Call 604-534-4312 or contact us online with your questions.