Are the Radii R1 and R2 of a Lens Always the Same?

[logearav]

Homework Statement

A lens is a transparent refracting medium bounded by two spherical surfaces.R1 and R2 are radii of two surfaces.

Homework Equations

Will the Radii R1 and R2 will be same or different ?

The Attempt at a Solution

I hope that they are same, otherwise there won't be symmetry. Still doubts lingers. Revered members can help.

 

[NascentOxygen]

I hope that they are same, otherwise there won't be symmetry.

Why would you see symmetry as being important, in a lens? How could you go about determining what would be the effect if the radii were not identical?

 

[logearav]

Ok, symmetry is not important. Agreed. So, radii of two spherical surfaces that constitute a lens can be different. Am I right?

 

[ehild]

Look at this: http://en.wikipedia.org/wiki/Lens_(optics)#Types_of_simple_lenses

ehild