How Do Contact Lenses Correct Myopia and Alter Near Point Vision?

Thread starter Dzano
Start date Jan 13, 2023
Tags

Focal length Optic lens

AI Thread Summary

Contact lenses for correcting myopia should be concave lenses, which diverge light rays to extend the far point of vision. The focal length of these lenses can be calculated using the formula for myopia correction, which involves the patient's far point. When using corrective lenses, the near point of the patient will improve, allowing for clearer vision at closer distances. The specific near point after lens correction can be determined through calculations based on the lens power. Overall, concave lenses effectively enhance near point vision in myopic individuals.

Jan 13, 2023

Dzano

New user has been reminded to always show their work when posting schoolwork questions

Homework Statement: The patient is myopic.

Relevant Equations: 1/f=1/p+1/q

Its near point is 13.0 cm from the eyes and its far point is 50.0 cm.
a) What type of contact lenses should be prescribed to correct his nearsightedness.
Determine their focal length
b) Determine the near point of the patient when using lenses for the correction of myopia.

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Jan 13, 2023

jim mcnamara

Mentor

Show us what you have tried, please. Question a - what type of lens? -- for example

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