Cinder Lenses Research Paper

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Recommended: anatomy and physiology note of eyes

The eye is complex part of the body which is capable of much. But like any body part, it is common for the eye to function incorrectly.
The eye is essentially an opaque sphere filled with vitreous gel. At the front of the eyeball is a transparent opening known as the cornea. It is a meniscus lens, with an approximate index of refraction of 1.38. The anterior surface of the cornea is the interface between the air and the eye, and is by far the surface with the highest refractive power in the eye, by about 48D (dioptres). Dioptres are units of refractive power. The purpose of the cornea includes, protecting the eye and refracting light as it enters the eye. Though, after light passes through the cornea and crystalline lens, a portion of it passes through the pupil.
The pupil is an opening that allows light to enter the eye. The size of the pupil opening can be adjusted by the dilation and constriction of the iris. The iris is capable of stretching and reducing the size of the …show more content…

Spherical lenses have a single dioptric power and create a single point of focus. They have the same power in all meridians of the lens and a single radius of curvature. These lenses can also correct myopia and hyperopia, but alone cannot correct astigmatism by itself.
A cylindrical lens surface have no power in one direction and the maximum power is 90° away. The surface of the cylinder having no power is referred to as the axis. With this cylindrical lens component, astigmatism can be corrected.
With spherocylinder lenses, the front surface of the lens is spherical and the back surface is cylindrical. This combination of front and back surfaces creates a lens that corrects astigmatism. The sphere power is located along the axis and the sphere and cylinder power combined are present 90° away from axis, allowing for all rays to be refracted

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