The Human Eye

Anatomy

How does the eye work?

The eye acts like a converging lens by producing a small, inverted and real image on the retina. The shape of the lens on the eyeball will change, this changes the length of the lens and allows focus on the retina.

Rods vs Cones

Rods: Responsible for detecting light intensity

Cones: Responsible for detecting colours

Eye disorders and solutions

Glaucoma

Symptoms: Intense pain, red eye, cloudy cornea

Solutions: Eye drops, pills, surgery

Damage to the optic nerve and increased pressure in the eye

Cataracts

An opaque, cloudy area that develops in the clear lens. It gradually blocks or distorts the light reducing visions

Causes: Eye injuries or infections, diabetes, drugs, genetics

Solution: Surgery where an intraocular lens is implemented

Astigmatism

The cornea is not smooth, therefore the rays of light entering the eye do not focus properly

Solution: Laser eye surgery

Myopia

When the distance between the lens and retina is too large. Image focuses in front of the retina

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Solution: Can be fixed with a diverging concave lens

Hyperopia

When the distance between the lens and the retina is too small. Image focuses in front of the retina

Solution: Can be fixed with a diverging concave lens

Presbyopia

The gradual loss of your eyes ability to of focus on nearby objects

Solutions: Glasses or contact lenses

Symptom: Difficulty seeing far away objects

Symptom: Difficulty seeing close objects

Symptoms: Blurred and distorted vision, eyestrain, headaches

Symptoms: Blurred vision at a normal viewing distance, eyestrain or headaches after reading