Imaging device and image processing method

Abstract

An imaging device includes an imaging unit including a plurality of pixels, respectively including photoelectric converters and charge accumulation nodes that accumulate signal charge. The imaging unit outputs image data based on signals corresponding to the signal charge accumulated in the charge accumulators. The imaging device includes an image processing unit that processes the image data output by the imaging unit. The imaging unit sequentially outputs a plurality of pieces of image data in one frame period by performing readout nondestructively. The image processing unit generates difference image data by determining a difference between two pieces of image data, selects output image data from initial image data and the difference image data, and combines the output image data and normal readout image data included in the plurality of pieces of image data, to generate combination-result image data.

What is claimed is: 
     
         1 . An imaging device comprising:
 an imaging unit that includes a plurality of pixels, respectively including photoelectric converters that generate signal charge and charge accumulators that accumulate the signal charge wherein the imaging unit outputs image data based on signals corresponding to the signal charge accumulated in the charge accumulators; and   a processing circuit that processes the image data output by the imaging unit,   wherein the imaging unit sequentially outputs a plurality of pieces of image data in one frame period by performing readout nondestructively a plurality of times, and subsequently resets the charge accumulators to output a piece of image data corresponding to a reset voltage, and   the processing circuit
 generates first image data based on at least one of the plurality of pieces of image data, 
 generates second image data by deriving a difference between the last one of the plurality of pieces of image data and the piece of image data corresponding to the reset voltage, and 
 combines the first image data and the second image data to generate third image data. 
   
     
     
         2 . The imaging device according to  claim 1 ,
 wherein each of the photoelectric converters includes a first electrode, a second electrode, and a photoelectric conversion layer between the first electrode and the second electrode.   
     
     
         3 . The imaging device according to  claim 1 ,
 wherein each of the photoelectric converters includes a photodiode.   
     
     
         4 . The imaging device according to  claim 1 ,
 wherein the imaging unit includes a signal readout circuit.   
     
     
         5 . The imaging device according to  claim 1 ,
 wherein the processing circuit generates the first image data by deriving a difference between two pieces of image data of the plurality of pieces of image data.   
     
     
         6 . The imaging device according to  claim 1 ,
 wherein the processing circuit generates the first image data by deriving a difference between two pieces of image data of the plurality of pieces of image data.   
     
     
         7 . The imaging device according to  claim 1 ,
 wherein the third image data has greater dynamic range than each of the first image data and the second image data has.   
     
     
         8 . An image processing method comprising:
 sequentially inputting a plurality of pieces of image data obtained by performing readout nondestructively a plurality of times in one frame period;   inputting a piece of image data corresponding to a reset voltage;   generating first image data based on at least one of the plurality of pieces of image data;   generating second image data by deriving a difference between the last one of the plurality of pieces of image data and the piece of image data corresponding to the reset voltage; and   combining the first image data and the second image data to generate third image data.   
     
     
         9 . The image processing method according to  claim 8 ,
 wherein the third image data has greater dynamic range than each of the first image data and the second image data has.