how can we know the person is suffering from which eye defect with the help of power ??
Answers
(1) Due to high converging power of eye-lens (because of its short focal length)
(1) Due to high converging power of eye-lens (because of its short focal length)In an eye suffering from myopia, the ciliary muscles attached to the eye-lens do not relax sufficiently to make the eye-lens thinner to reduce its converging power. So, due to the greater converging power of the eye-lens in myopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.
(1) Due to high converging power of eye-lens (because of its short focal length)In an eye suffering from myopia, the ciliary muscles attached to the eye-lens do not relax sufficiently to make the eye-lens thinner to reduce its converging power. So, due to the greater converging power of the eye-lens in myopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.(2) Due to eye-ball being too long
(1) Due to high converging power of eye-lens (because of its short focal length)In an eye suffering from myopia, the ciliary muscles attached to the eye-lens do not relax sufficiently to make the eye-lens thinner to reduce its converging power. So, due to the greater converging power of the eye-lens in myopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.(2) Due to eye-ball being too longIn the eye suffering from myopia, the eye-ball is too long due to which the retina is at a larger distance from the eye-lens. This condition also results in the formation of the image of a distant object in front of the retina (even though the eye-lens may have correct converging power)
(1) Due to high converging power of eye-lens (because of its short focal length)In an eye suffering from myopia, the ciliary muscles attached to the eye-lens do not relax sufficiently to make the eye-lens thinner to reduce its converging power. So, due to the greater converging power of the eye-lens in myopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.(2) Due to eye-ball being too longIn the eye suffering from myopia, the eye-ball is too long due to which the retina is at a larger distance from the eye-lens. This condition also results in the formation of the image of a distant object in front of the retina (even though the eye-lens may have correct converging power)The parallel rays of light coming from the distant object O (at infinity) are converged to form an image in front of the retina due to which the eye cannot see the distant object clearly.The image is formed in front of the retina either due to high converging power of eye lens or due to eye ball being too long.
(1) Due to high converging power of eye-lens (because of its short focal length)In an eye suffering from myopia, the ciliary muscles attached to the eye-lens do not relax sufficiently to make the eye-lens thinner to reduce its converging power. So, due to the greater converging power of the eye-lens in myopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.(2) Due to eye-ball being too longIn the eye suffering from myopia, the eye-ball is too long due to which the retina is at a larger distance from the eye-lens. This condition also results in the formation of the image of a distant object in front of the retina (even though the eye-lens may have correct converging power)The parallel rays of light coming from the distant object O (at infinity) are converged to form an image in front of the retina due to which the eye cannot see the distant object clearly.The image is formed in front of the retina either due to high converging power of eye lens or due to eye ball being too long.The far point of eye having myopia (or short-sightedness) is at point F which is less than infinity. The rays of light coming from the person’s far point F can just be focused by his eye on the retina. If the distant object can be made to appear as if it were at the far point F of this eye, then the eye can see it clearly. This is done by putting a concave lens in front of the eye.
Hope it helps........( ^ v ^)