Advertisements
Advertisements
प्रश्न
Differentiate the eye defects: Myopia and Hypermetropia
Advertisements
उत्तर
| Myopia | Hypermetropia |
| Myopia, also known as short-sightedness, occurs due to the lengthening of the eyeball. | Hypermetropia, also known as long-sightedness, occurs due to the shortening of the eyeball. |
| With this defect, nearby objects can be seen clearly but distant objects cannot be seen clearly. | With this defect, distant objects can be seen clearly but nearby objects cannot be seen clearly. |
| The focal length of the eye lens is reduced or the distance between the eye lens and retina increases. | The focal length of the eye lens is increased or the distance between the eye lens and retina decreases. |
| The far point will not be infinity for such eyes and the far point has come closer. | Hence, the near point will not be at 25 cm for such eyes and the near point has moved farther. |
| Due to this, the image of distant objects is formed before the retina. | Due to this, the image of nearby objects is formed behind the retina. |
| This defect can be corrected using a concave lens | This defect can be corrected using a convex lens. |
APPEARS IN
संबंधित प्रश्न
What is the other name for
hypermetropia
What is the scientific name of
short-sightedness
A man can read the number of a distant but clearly but he finds difficulty in reading a book.
What type of spectacle lens should he use to correct the defect?
A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:
if the person is an old man
A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision:
if the person is a young man
Have a look at the posture of this girl who is reading a book and answer the questions which follow:
Name the problem she is facing.
Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:
Name the parts labeled 1 to 4.
Give Reason:
Older people require glasses to read and write.
In Myopia the human eye _______.
Nearsightedness : concave lens : : farsightedness : _______
