High-efficiency, multilevel, diffractive optical elements

Claim 2

Method for making high-efficiency, multilevel, diffractive optical elements comprising: generating at least one binary amplitude mask including multilevel information, the mask being configured to provide 2 N levels where N is the number of masks; and utilizing the masks' information for constructing 2 N levels in the optical element, the depths of the levels being related by a fixed ratio.

Claim 3

The method of claim 1 wherein the masks are made by lithographic pattern generators.

Claim 4

The method of claim 1 including three masks and eight levels.

Claim 5

The method of claim 1 wherein the binary amplitude masks are defined by calculating equiphase boundaries utilizing the equation ##EQU5## and the algorithm ______________________________________ Equi-phase Phase Boundaries Etch Mask # N (l = 0, ±1, ±2, . . . ) Depth θ ______________________________________ 1 φ(x,y) = (l + 1)π π ##STR5## π/2 3 ##STR6## π/4 4 ##STR7## π/8 ______________________________________

Claim 6

The method of claim 1 wherein the masks are made by electron beam pattern generators.

Claim 7

The method of claim 1 wherein the optical element is a lens.

Claim 8

The method of claim 1 wherein the optical element corrects for spherical aberration.

Claim 9

The method of claim 1 wherein the optical element is corrected for chromatic aberration.

Claim 10

Method for making high-efficiency multilevel diffractive optical elements comprising: making a master optical element according to the method of claim 1; and using the master optical element to emboss multiple replicated optical components.

Claim 11

The method of claim 9 wherein the master optical element is copied in metal which is used for the embossing.

Claim 12

Method for making a high efficiency, multi-level, diffractive optical element comprising: providing a substrate including at least two initial levels; generating at least one binary amplitude mask including multi-level information; and utilizing the mask to double the number of levels in the element.

Claim 13

Method for making a high efficiency, multi-level, diffractive optical element comprising: providing a substrate including at least two initial levels; generating at least one binary amplitude mask including multi-level information; and utilizing the mask to double the number of levels in the element.