The Human Eye

(a) Name the eye disorder she is suffering from.
The eye disorder Tara's grandmother is suffering from is known as {Presbyopia}. This is an age-related disorder where the ability to focus on nearby objects decreases due to the hardening of the lens and weakening of the eye's ciliary muscles. (b) How can the above defect be corrected?
Presbyopia can be corrected using {bifocal} or {reading glasses}, or in some cases, {contact lenses}. These help to focus on nearby objects by compensating for the loss of accommodation. (c) Where is the image formed in the above disorder?
In presbyopia, the image is formed behind the retina due to the inability of the eye lens to change its shape adequately to focus on close objects.

Step 1: Define the Defect.
This condition is known as {astigmatism}. Astigmatism occurs when the curvature of the cornea or lens of the eye is irregular, causing light to focus on multiple points instead of a single point on the retina.
Step 2: Cause of Astigmatism.
In a normal eye, light is refracted evenly to focus on a single point on the retina, creating a clear image. However, in an eye with astigmatism, the irregular curvature of the cornea or lens causes light to be focused at multiple points, leading to blurred vision, especially for objects at certain distances.
Step 3: Symptoms and Correction.
People with astigmatism may experience blurred vision, eye strain, and headaches. The condition can be corrected with eyeglasses, contact lenses, or surgery, depending on its severity.