Chromatic polarization filtering that is input specific
AssigneeGary Sharp Innovations, LLC
InventorsGary D. Sharp, Anthony D. McGettigan
Life of this patent
Estimating the term…
Abstract
Optical filters that enhance image quality by exploiting differences in the wavelength dependence of the spectral power distribution (SPD) and the degree of polarization between elements in a scene in order to preserve, and more preferably enhance, color-contrast between one or more salient objects in the scene and/or a salient object and a background. The higher degree of polarization may be associated with the background or the one or more salient objects. Color contrast is associated with one or more of a difference in saturation, a difference in hue, and a difference in lightness.
Claims21
An optical filter receptive of incoming light having at least a chromatic unpolarized volume scatter component and a polarized surface scatter component, the unpolarized volume scatter component having a first spectral power distribution (SPD), wherein the polarized surface scatter component has an angular orientation, the filter comprising:
- one or more optical elements that together have an orientation-sensitive spectral transmission function for filtering the polarized surface scatter component of the incoming light differently from the unpolarized volume scatter component of the incoming light.
An optical filter receptive of incoming light having at least a chromatic unpolarized volume scatter component and a polarized surface scatter component, wherein the polarized surface scatter component has an angular orientation, the filter comprising:
- a chromatic polarizer with an absorption axis oriented parallel to the angular orientation of the polarized surface scatter component;
- wherein a transmission spectrum along the absorption axis of the chromatic polarizer shifts a color coordinate of the polarized surface scatter component of the incoming light toward a color coordinate of the unpolarized volume scatter component of the incoming light.
An optical filter receptive of incoming light having at least a chromatic unpolarized volume scatter component and a polarized surface scatter component, wherein the polarized surface scatter component has an angular orientation, the filter comprising:
- one or more input retarders configured to produce a wavelength-dependent state-of-polarization;
- a linear polarizer receptive of light passing through the one or more input retarders, the linear polarizer having an absorption axis oriented either parallel to or perpendicular to the angular orientation of the polarized surface scatter component of the incoming light;
- wherein the transmission spectrum of the optical filter shifts a color coordinate of the polarized surface scatter component of the incoming light toward a color coordinate of the unpolarized volume scatter component of the incoming light.
Dependencies are inferred from the claim text.