Question1

Questions 1-6:Design an achromatic doublet with a sodium D focal length of 50 mm using the N-BAF10 crown and SF10 flint glasses used in the lecture. Constrain the interior surface that is mutual to both singlets to have zero curvature. This might be the starting point for optimization during which that interior curvature would be varied and the exterior curvatures solved from the constraints you will derive here.

Question2

What is the focal length of the flint singlet in mm to one decimal point? Verify that the two singlets have equal and opposite changes in power over the visible spectrum.

Question3

What is the expected change in effective focal length F_CF_F of the positive singlet over the visible spectrum (in mm to two decimal points)? Note that the quantity requested is positive for a positive power lens.

Question4

What is the expected change in effective focal lengthF_CF_F of the negative singlet over the visible spectrum (in mm to one decimal point)? Note that the quantity requested is negative for a negative power lens.

Question5

What is the radius of curvature of the first surface (the air/crown interface) in mm to one decimal point? Approximate the lenses as thin (d = 0).

Question6

What is the radius of curvature of the third surface (the flint/air interface) in mm to one decimal point? Approximate the lenses as thin (d = 0).