Patent ID: 8743459
Filing Date: 2014-06-03
Classification: G02B

Abstract:
1. A diffractive element comprising a diffractive optical microstructure comprising a modulated structure of a diffractive type which upon illumination by diffused ambient light creates a two-dimensional image to be viewed by an observer upon tilting or rotating the device or by varying lighting direction, wherein the diffractive modulated structure of the device comprises a plurality of optical elements with specifically prescribed groove shapes combining to form a three-dimensional pattern of the structure, wherein any one of the grooves is described by a continuously varied parameterized functions employing at least two parameters which vary between the grooves of the structure to form the said three-dimensional pattern, wherein the parameters are selected from a group consisting of groove shape, position, center and line thickness, and wherein the functions further serving to describe functional dependencies which are variables of a positional coordinate of the optical element.