Patent ID: 6836365
Filing Date: 2004-12-28
Classification: G02B,G03F,Y10S

Abstract:
A diffractive optical element that converts an input light beam into an output light having a specified cross-sectional shape in a specified plane which is set in a vicinity of a focal plane of a lens or in a substantially far field plane from said diffractive optical element, the diffractive optical element comprising:a plurality of partial optical elements, wherein each of the plurality of partial optical elements converts the input light beam into a respective partial light beam which substantially illuminates a division of said specified cross-sectional shape, wherein the plurality of partial optical elements have a first partial optical element which converts the input light beam into a first partial light beam, and a second partial optical element which converts the input light beam into a second partial light beam, wherein the first and the second partial light beams are adjacent to each other at the specified plane, and wherein the first and the second partial optical elements are separated from each other, wherein the partial optical elements have a power; a sum of the respective partial light beams of all of the plurality of partial optical elements matches the specified cross-sectional shape of the output light beam, wherein said each of the plurality of partial optical elements have a respective zoned diffractive pattern which substantially corresponds to a pattern within a unique divided zone of a diffractive lens respectively, said each zoned diffractive pattern has an arc, a center of curvature of the arc is decentered from a center of the partial optical element, wherein said each zoned diffractive pattern of said partial optic elements can be connected in a substantially continuous manner while superposing each center of curvature of said arc, and a shape of a border line of a whole continued pattern of all zoned diffractive patterns substantially has a figure similar to said specified cross-sectional shape.