Image sensor with stripes of cyan filter material perpendicular to stripes of yellow filter material

Abstract

A CCD image sensor with a color filter array (CFA) for color imaging involves stripes of Cyan and of Yellow filter material on the imaging surface of a CCD array, preferably a full-frame (FF) CCD imager, with the two sets of color stripes arranged perpendicular to each other and one set parallel to the array axes to form two layers at the areas where they cross. Unit color cells comprise 2-pixel by 2-pixel blocks, each containing a Cyan, a Yellow, a Green (where the stripes overlap), and a White (where there is no stripe) pixel. Also, the longitudinal set can be segmented into two pixels or more in length, and the segments transversely displaced or staggered to form an elongated checkerboard pattern to compensate for devices with single-column blemishes. In fabrication, the filter stripes of one color are deposited crossing over the others to form two layers with different thicknesses so that the later deposited stripe has spectral properties in the cross-over regions distinctly different from non-cross-over regions, permitting the production of a four-color image CCD sensor chip with fewer fabrication steps and improved yield. The resulting chip has the sensed image charge read out after only one exposure to generate the desired color image data file, and a 2×2 pixel block of a unit cell can be virtually shifted by one pixel both longitudinally and transversely so that complementary 2×2 pixel blocks can also be used to generate unique color image data. Another arrangement using Cyan and Yellow filter material in the form of circular discs or octagons is also disclosed.