Determine what is the function of bifocal spectacles

Reference no: EM13336882

In an eye that is farsighted, the eye focuses parallel rays so that the image would form behind the retina. In an eye that is nearsighted, the image is formed in front of the retina.

a) How would you design a corrective lens for each defect? Make a ray diagram for each case.

b) If you need spactacles only for reading, are you nearsighted or farsighted?

c) What is the function of bifocal spectacles, in which the upper parts and lower parts have different focal lengths?

Reference no: EM13336882

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