Q. (a) What is astigmatism? How is it caused? How can it be corrected?

1.	Q. (a) What is astigmatism? How is it caused? How can it be corrected?(b) A person is unable to see both far as well as near objects. What is the defect he is suffering from? What could be the reason for this defect? What type of spectacles should be worn by him to correct his vision......?????
Answer» $\huge \red {\underline {HAYE\:MATE}}$ $\huge \red {\mathbb {ANSWER}}$ *(a)* *Astigmatism* : The defect by which the person is not able to differentiate horizontal and VERTICAL position, is called astigmatism. *Causes of Astigmatism: Astigmatism is CAUSED by an unevenly shaped cornea.* The uneven shape causes the rays of light to focus on two points on the retina, causing distortion and BLURRING of images. *Correction of astigmatism:* This defect of vision can be rectified by using cylindrical lenses. (b)presbyopia The defect of eye in which a person is UNABLE to see both far as well as near objects clearly is called presbyopia. *Causes of presbyopia:* This defect of vision commonly occurs to old people because of the following reasons: *Weakening of the ciliary musclesReduction in the flexibility of the eye lensCorrection of presbyopia:* This type of defect can be corrected by using spectacles having bi-focal lenses in which upper part consists of a concave lens to correct myopia (shortsightedness) used for distant VISIONS and the lower part consists of a convex lens to correct hypermetropia (long sightedness) sused for reading purposes. $\huge \blue {\mathbb {THANKS}}$ $\huge \green {FOllOW\:ME}$ $\huge \purple {\mathbb {SINGLE\:STAR}}$

Q. (a) What is astigmatism? How is it caused? How can it be corrected?(b) A person is unable to see both far as well as near objects. What is the defect he is suffering from? What could be the reason for this defect? What type of spectacles should be worn by him to correct his vision......?????

Answer»

$\huge \red {\underline {HAYE\:MATE}}$

$\huge \red {\mathbb {ANSWER}}$

(a) Astigmatism :

The defect by which the person is not able to differentiate horizontal and VERTICAL position, is called astigmatism.

Causes of Astigmatism:

Astigmatism is CAUSED by an unevenly shaped cornea.
The uneven shape causes the rays of light to focus on two points on the retina, causing distortion and BLURRING of images.

Correction of astigmatism:

This defect of vision can be rectified by using cylindrical lenses.

(b)presbyopia

The defect of eye in which a person is UNABLE to see both far as well as near objects clearly is called presbyopia.

Causes of presbyopia:

This defect of vision commonly occurs to old people because of the following reasons:

Weakening of the ciliary musclesReduction in the flexibility of the eye lensCorrection of presbyopia:

This type of defect can be corrected by using spectacles having bi-focal lenses in which upper part consists of a concave lens to correct myopia (shortsightedness) used for distant VISIONS and the lower part consists of a convex lens to correct hypermetropia (long sightedness) sused for reading purposes.

$\huge \blue {\mathbb {THANKS}}$