How the eye works
The process of changing the shape of the lens of the eye to focus on near or distant objects. is the process of changing the shape of the lens to focus on near or distant objects.
To focus on a near object – the lens becomes thicker, this allows the light rays to Process by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ray changes direction when refracted by a lens. more strongly.
To focus on a distant object – the lens is pulled thin, this allows the light rays to refract slightly.
| Position of object | Ciliary muscles | Suspensory ligaments | Muscle tension on lens | Lens shape | Refraction of light rays |
| Near | Contract | Slacken / loosen | Low | Fat / thicker | Light is refracted strongly |
| Distant | Relax | Stretch / tighten | High | Thin | Light is refracted slightly |
| Position of object | Near |
|---|---|
| Ciliary muscles | Contract |
| Suspensory ligaments | Slacken / loosen |
| Muscle tension on lens | Low |
| Lens shape | Fat / thicker |
| Refraction of light rays | Light is refracted strongly |
| Position of object | Distant |
|---|---|
| Ciliary muscles | Relax |
| Suspensory ligaments | Stretch / tighten |
| Muscle tension on lens | High |
| Lens shape | Thin |
| Refraction of light rays | Light is refracted slightly |
The lens changes shape to focus on near and distant objects
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