Patent ID: 6829417
Filing Date: 2004-12-07
Classification: G02B,G02F

Abstract:
An optical apparatus, comprising an optical element having a set of at least two diffractive elements, whereineach diffractive element diffracts a corresponding diffracted component of an incident optical field with a corresponding diffractive element transfer function so that the diffractive element set collectively provides an overall set transfer function between an entrance optical port and an exit optical port, each diffractive element comprises at least one diffracting region and is spatially defined with respect to a corresponding one of a set of diffractive element virtual contours, the diffracting regions having at least one altered optical property so as to enable diffraction of a portion of the incident optical field, the virtual contours of the diffractive element virtual contour set are spatially arranged so that, if diffracting regions of the corresponding diffractive elements were to spatially coincide with the virtual contours, the resulting superposition of the diffracted field components at a design wavelength would exhibit maximal constructive interference at the exit port, and at least one of: i) the overall set transfer function; and ii) at least one corresponding diffractive element transfer function, is determined at least in part by displacement of at least one diffracting region relative to the corresponding virtual contour and relative to at least one other diffracting region of the corresponding diffractive element.