Blindness means a person may be "legally blind" with either 20/200 vision in both eyes with best correction, or a field of vision restricted to 200 or less.

In the psychology context, blindness refers to a condition where a person is unable to see or has significant difficulty in seeing. Blindness can be caused by various factors, such as genetics, disease, injury, or aging. It can be classified into two main categories: partial or complete blindness.

Examples of conditions that can cause blindness include:

  1. Congenital cataracts: This is a condition where the lens in a baby's eye is cloudy, leading to vision problems and possibly blindness.

  2. Diabetic retinopathy: This is a complication of diabetes that can cause damage to the blood vessels in the retina, leading to vision loss and blindness.

  3. Glaucoma: This is a condition where the optic nerve is damaged, leading to vision loss and blindness.

  4. Macular degeneration: This is a condition where the central part of the retina is damaged, leading to vision loss and blindness.

  5. Retinitis pigmentosa: This is a genetic condition that causes gradual vision loss and can eventually lead to blindness.

  6. Trauma: Injuries to the eye or head can cause blindness, such as a blow to the head or penetrating eye injury.

Blindness can have significant psychological impacts on an individual's life, such as affecting their independence, mobility, and social interactions. However, many people with blindness are able to lead fulfilling lives by learning to adapt and use assistive devices such as Braille or text-to-speech software.