Achromatic imaging lens with extended depth of focus

摘要

A lens includes a diffractive surface having an etched structure and a refractive surface having a curved structure. The lens reduces chromatic aberration of incident light and extends depth of focus. In one alternative, the etched structure is a calculated phase pattern or a pattern that is embossed or diamond tuned. In another alternative, the curved structure is convex shaped or concave shaped. In yet another alternative, the lens is an imaging lens wherein high lateral resolution of incident light is preserved.