# Plano-convex lens

paulstgeorge
Can someone help me with the Lensmaker's equation for a plano-convex lens? The formula for a bi-convex lens is readily available but it includes a term for the radius for each of the two curves. A plano-convex lens has only one radius!

Homework Helper
Gold Member
Let the second radius go to infinity.

paulstgeorge
Thanks. Does that mean the formula is simplified to the formula shown in simple2.jpeg?

Whether I start with the formula shown in simple1.jpeg or that shown in complex.jpeg, if the second radius is infinity a number of terms are then zero.

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• simple2.jpeg
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• simple1.jpeg
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• complex.jpeg
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lightarrow
Thanks. Does that mean the formula is simplified to the formula shown in simple2.jpeg?

Whether I start with the formula shown in simple1.jpeg or that shown in complex.jpeg, if the second radius is infinity a number of terms are then zero.
Certainly.