An achromatic double glued lens is made by gluing a low refractive index corona glass positive lens to a high refractive index flint glass negative lens. The tw...
A biconvex lens is a lens in which both sides are convex, usually their curvatures are equal, and is used primarily to converge light from a point source or to ...
A biconcave lens is one in which both sides of the lens are concave. A biconcave lens has a negative focal length, which allows the beam to diverge. Therefore, ...