Final answer:
People with poor eyesight, such as farsightedness or nearsightedness, can see clearly with the help of glasses or contact lenses. In the case of cataracts, the removal of the lens may allow people to see low-frequency ultraviolet light.
Step-by-step explanation:
People with poor eyesight may have different vision problems, such as farsightedness (hyperopia) or nearsightedness (myopia). Farsighted people can see distant objects clearly, but nearby objects appear blurry because the eye is too short. Nearsighted people can see nearby objects clearly, but distant objects appear blurry because the eye overconverges the nearly parallel rays. Vision problems can be corrected with glasses or contact lenses that help focus the light properly on the retina. In the case of cataracts, where the lens of the eye is removed, people may be able to see low-frequency ultraviolet due to the removal of the lens, which filters out some ultraviolet light.