Aspherical lenses appeared in England at the end of the 15th century, and were proposed as a solution to the optical aberrations produced by spherical lenses.
The more complex aspherical profile can eliminate spherical aberration and reduce other optical aberrations compared to simple (constant radius) lenses, so their use can reduce the number of lenses needed in a system, making it lighter and smaller.
The surface can follow an elliptic, parabolic, hyperbolic curve or follow a mathematical function whose coefficients can be customized.
In the lighting field aspherical lenses are normally used as the first element near the light source to concentrate the radiation (also called collimating lenses), as they are able to converge also the rays that affect them very marginally. Ultimately aspherical lenses contribute to a greater light or signal transfer if used specifically as entry lenses placed in front of a source.
Thanks to the production line Free Form IODA can produce Aspherical lenses at the customer’s request, in diameters between 15 and 180mm.