A spherical surface is defined by only one parameter, the radius or curvature of the surface. If the surface is refractive, with different indices of refraction before and after the surface, then the ...

Ever wondered why Earth looks flat even though it's a sphere? The planet's massive size makes its curvature nearly impossible ...

Visible - used within the 380 to 750 nm range. Ultraviolet - used within the 4 to 380 nm range. Other geometric lens specifications — such as radius of curvature, surface height, optical center, and ...