An achromatic doublet must have power +2.5 D. Its component dispersive powers are 0.020 and 0.050. Determine component powers P₁ and P₂.
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An achromatic doublet must have power +2.5 D. Its component dispersive powers are 0.020 and 0.050. Determine component powers P₁ and P₂.

G1 Physics · Accepted Answer

Solve P₁+P₂=2.5 and ω₁P₁+ω₂P₂=0: P₁=4.17 D, P₂=-1.67 D.