What does 'Aspherical' mean?

[AndyWest]

I see it regarding lenses including my new Tamron so what does it mean?

 

[del69]

Maybe............http://en.wikipedia.org/wiki/Aspheric_lens

 

[SealBeard]

I think this explains it more or less in the first paragraph

clicky

gah! beaten to it

 

[AndyWest]

Thanks peeps! i Should have gone to Specsavers! and looked it up for myself...too lazy today