The eye lens works by bending (refracting) light to focus it precisely onto the retina, enabling clear vision.
Here's a more detailed explanation:
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Light Enters the Eye: Light rays first pass through the cornea, the clear outer layer of the eye, which begins the focusing process. The pupil, controlled by the iris, regulates the amount of light that enters.
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Lens Focuses the Light: After passing through the pupil, light reaches the lens. The lens is a flexible, transparent structure located behind the iris.
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Accommodation (Changing Shape): The lens can change its shape to focus on objects at varying distances. This process is called accommodation.
- Distant Objects: When looking at distant objects, the ciliary muscles surrounding the lens relax, causing the lens to become thinner and flatter. This allows light from distant objects to be focused on the retina.
- Near Objects: When looking at near objects, the ciliary muscles contract, causing the lens to become thicker and more curved. This increased curvature allows the lens to focus light from near objects onto the retina.
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Retinal Projection: The focused light then projects an image onto the retina, the light-sensitive tissue at the back of the eye.
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Signal Transmission: The retina converts the light into electrical signals, which are then sent to the brain via the optic nerve. The brain interprets these signals as images, allowing us to see.
In essence, the eye lens functions like the lens in a camera, focusing light to create a sharp image. Its ability to change shape, or accommodate, is crucial for clear vision at different distances.
