OPTICAL ELEMENTS WITH GRADIENT REFRACTIVE INDEX AND OPTICAL SYSTEMS INCLUDING SUCH OPTICAL ELEMENTS

摘要

An optical element includes a first surface and an opposed second surface. A refractive index of the optical element varies from a center of the optical element to a perimeter of the optical element such that the optical element is configured to convert a Gaussian input beam introduced to the first surface into an output beam from the second surface with a substantially flat irradiance profile along at least one axis. The optical element can have a refractive index that varies along an axis perpendicular to the optical axis of the optical element and has a profile that is concave up at a center of the optical element.