Micro-lenses for cmos imagers and method for manufacturing micro-lenses

An imaging system comprising:

• an imager having a micro-lens array, the micro-lens array comprising:
• a semiconductor substrate positioned over an array of pixel cells, the semiconductor substrate having a bottom surface facing towards the pixel cells and an upper surface opposite the bottom surface;
• an opening in the semiconductor substrate recessed below the upper surface of the substrate, the opening serving as a mold for a plurality of micro-lenses;
• and
• a lens material located within the opening mold of the semiconductor substrate, wherein the lens material forms the plurality of micro-lenses, each of the micro-lenses having a respective focal point, wherein the focal point of at least one of the plurality of micro-lenses differs from the focal point of at least one other of the plurality of micro-lenses.

A system comprising:

• a processor;
• and
• an imaging device, the imaging device comprising:
• a plurality of pixel cells each having a photosensor;
• a plurality of color filters respectively associated with said pixel cells;
• and
• a micro-lens array including a plurality of micro-lenses each associated with one of said pixel cells, each micro-lens having a focal point, where the focal points of the micro-lenses change across the micro-lens array.