All eyeglass lenses have chromatic aberration. This is usuallyexpressed as dioptric spread. For a typical +6.0 D lens,the focusing power for red light is +5.90 D,the power for greenlight is +6.00 D, and the power for blue light is +6.10 D. Thisgives a dioptric spread of 0.20 diopter. Suppose a myopic person isobserving a distant object through this lens, and the green lightof the image is in perfect focus. Assume a distance s′ = 1.7000cm.
a. How far in front of or behind the retina is the point ofsharp focus for red light?
Express your answer with the appropriate units. Enter positivevalue if the point of sharp focus is behind the retina and negativevalue if the point of sharp focus is in front of the retina.
b. How far in front of or behind the retina is the point ofsharp focus for blue light?
Express your answer with the appropriate units. Enter positivevalue if the point of sharp focus is behind the retina and negativevalue if the point of sharp focus is in front of the retina.
