Question

a person with myopic eye cannot see objects beyond a distance of 1.5m. what is the power of the corrective lens used to restore proper vision?

Answer 1

u = infinity v = -1.5m

P = 1/f = 1/u - 1/v

=1/-15 =-0.66 D

Answer 2

Answer:

The power of myopic corrective lens with vision at 1.5 m  =  -0.66 D

Explanation:

• To correct myopia or nearsightedness concave lens is used.
• Myopic persons cannot see objects beyond a distance of 1.5 m and hence the correction must be to reduce the eye’s focusing power, so minus lenses are used.
• The minus lenses focus the image directly on the retina. The power of lenses is expressed in Diopters.
• The lens power for a corrective myopic glass begins with a minus sign. The power of lens according to the lens formula is: $D = \frac{1}{f}$, where D is the lens power in Diopter and f the focal length.
• So if the focal length is 1-5 m, then the power of corrective lens for myopic patient would be:

                                        $D=\frac{1}{-1.5}=-0.66 D$

So, the power of myopic corrective lens with vision at 1.5 m  =  -0.66 D.