What type of lens is likely used in glasses for nearsightedness?

What type of lens is likely used in glasses for nearsightedness?

• A. Convex lens
• B. Concave lens
• C. Spherical lens
• D. Cylindrical lens

Answer: (B)

Nearsightedness, or myopia, occurs when the eye is unable to focus light directly on the retina, typically because the eyeball is too long relative to its optical power. This leads to distant objects appearing blurry while close objects can be seen clearly. To correct this condition, concave lenses are used in glasses. Concave lenses are shaped such that they are thinner at the center than at the edges. This design causes light rays entering the lens to diverge, which effectively extends the focal length of the light rays before they reach the retina. By diverging the light, concave lenses allow the image of distant objects to be brought into clearer focus on the retina, thus correcting the vision of someone who is nearsighted. Other lens types do not serve the same function for nearsightedness. For example, convex lenses are used for farsightedness (hyperopia) to converge light rays and help focus images on the retina. Spherical and cylindrical lenses refer to different shapes and purposes in correcting vision. Spherical lenses can be either concave or convex, while cylindrical lenses are specifically used to correct astigmatism, not nearsightedness. Thus, the use of concave lenses is essential in providing the necessary correction

Nearsightedness, or myopia, occurs when the eye is unable to focus light directly on the retina, typically because the eyeball is too long relative to its optical power. This leads to distant objects appearing blurry while close objects can be seen clearly. To correct this condition, concave lenses are used in glasses.

Concave lenses are shaped such that they are thinner at the center than at the edges. This design causes light rays entering the lens to diverge, which effectively extends the focal length of the light rays before they reach the retina. By diverging the light, concave lenses allow the image of distant objects to be brought into clearer focus on the retina, thus correcting the vision of someone who is nearsighted.

Other lens types do not serve the same function for nearsightedness. For example, convex lenses are used for farsightedness (hyperopia) to converge light rays and help focus images on the retina. Spherical and cylindrical lenses refer to different shapes and purposes in correcting vision. Spherical lenses can be either concave or convex, while cylindrical lenses are specifically used to correct astigmatism, not nearsightedness.

Thus, the use of concave lenses is essential in providing the necessary correction