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| A big eye is less curved, creating a narrower view-field and
less periferial view, it gives a more sharper view because minimal
diffraction (spreading) of the incoming light. | | | There are 3 places of curvature in an eye: 1. Cornea The cornea is the transparent front part of the eye that provides most its optical power. It refracts light and, as a result, helps the eye to focus. The cornea contributes more to the total refraction than the lens does, but, whereas the curvature of the lens can be adjusted to "tune" the focus, the curvature of the cornea is fixed.
2. Lens The lens is located just behind the iris. Its purpose is to focus light onto the Retina. The nucleus, the innermost part of the lens, is surrounded by softer material called the cortex. The lens is encased in a capsular-like bag and suspended within the eye by tiny "guy wires" called zonules. 3. Retina
The Retina is the innermost layer of the eye, it is made up of nerve cells. When we look directly at an object, its image falls on the Retina at a fixed spot, along the visual axis, that lies in a slight depression: the Fovea, this tiny area is responsible for our central, sharpest vision. Different sizes of lenses have different results: Large Diameter • converges more light • brighter image • focus becomes more critical • less depth of focus Small Diameter • dimmer image • focus becomes less critical • more depth of focus
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