Method and apparatus for preventing image artifacts
AssigneeGeneral Electric Company
InventorsScott William Petrick, Roland Frederick Saunders, Douglas I. Perry
Life of this patent
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Abstract
A pixel sensing subsystem (110) for a solid state image sensor includes frame timing logic (114) that produces a frame timing signal indicative of an end-of-frame time and a beginning-of-frame time and reset logic (116) that produces a reset signal for a charge accumulator of pixel sensing electronics. The reset logic (116) asserts the reset signal at least once between the end-of-frame time and the beginning-of-frame time to prevent saturation of the pixel sensing element.
Claims7
A pixel sensing subsystem for a solid state image sensor, the subsystem comprising:
- frame timing logic producing a frame timing signal indicative of an end-of-frame time and a beginning-of-frame time;
- pixel sensing electronics for producing an output signal indicative of charge on a pixel in the solid state image sensor;
- a switch coupling one of an imaging capacitor and a between frame capacitor to the pixel sensing element, wherein the between frame capacitor has a larger capacitance than the imaging capacitor;
- and
- a switch control input for directing the switch to couple the between frame capacitor to the pixel sensing electronics between the end-of-frame time and the beginning-of-frame time to prevent saturation of the pixel sensing electronics after image readout.
A method for preventing image artifacts during image readout from a solid state image sensor, the method comprising:
- determining an end-of-frame time indicative of image readout completion;
- determining a beginning-of-frame time indicative of image readout initiation;
- reading at least one live image between the beginning-of-frame time and end-of-frame time;
- and
- reading at least one dark image after the end-of-frame time to prevent saturation of pixel sensing elements for a subsequent live image readout.
Dependencies are inferred from the claim text.