Patent ID: 6735017
Filing Date: 2004-05-11
Classification: G02B,G02F,H04N

Abstract:
A broadband optical retardation device for receiving light consisting of a broad range of wavelengths, the device including patterned optical retardation means including a first region having a first optic axis at an orientation a between 0Â° and +90Â° to a reference plane and a second region in a same plane as the first region and having a second optic axis at an orientation b between 0Â° and âˆ’90Â° to the reference plane, and non-patterned optical retardation means having an optic axis at a defined orientation c, greater than the orientation a and less than the orientation 180Â°+b, to the reference plane in order to increase the achromaticity of the light polarised by the combination of the patterned optical retardation means and the non-patterned optical retardation means as compared with light polarised by the patterned optical retardation means alone, andwherein the orientations a and b of the first and second optic axes of the patterned optical retardation means are substantially equal and opposite relative to the reference plane, and the orientation c of the optic axis of the non-patterned retardation means is substantially perpendicular to the reference plane.