Optical Aspheric Lens

Aspheric lens or asphere is a lens whose surface profiles are not portions of a sphere or cylinder.
An aspheric lens can often replace a much more complex multi-lens system because the aspheric surface can reduce or eliminate spherical aberration compared to a simple lens. Integrating aspheres into an application such as focusing the output of a laser diode may not only decrease total cost, but may also outperform assemblies designed with traditional spherical optical lenses.
Optical Aspheric Lens