DEFECTIVE PIXEL SPECIFYING METHOD, DEFECTIVE PIXEL SPECIFYING SYSTEM, IMAGE CORRECTING METHOD, AND IMAGE CORRECTING SYSTEM

• US 20110254984A1
• Filed: 06/27/2011
• Published: 10/20/2011
• Est. Priority Date: 03/01/2001
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Hajime
• Granted Patent: US 8,130,291 B2
• Time in Patent Office: Days
• US Class Current: 348/246
• CPC Class Codes: H04N 9/30 using solid-state colour display devices

Abstract

A defective pixel specifying method and a defective pixel specifying system for a semiconductor device having a defective pixel are provided. Also provided are an image correcting method and an image correcting system for making a defective pixel inconspicuous on the screen when a read image is displayed. The present invention determines whether or not there is a defective pixel for each pixel and specifies the coordinate of the defective pixel using image signals obtained by reading a plurality of images. The image signal of the defective pixel is set based on the image signals of the pixels adjacent to the defective pixel to correct the image of the subject read.

Claims

1. A method of driving a device comprising a plurality of pixels, each comprising a first transistor and a photoelectric conversion element, comprising the steps of:

obtaining a first image signal of each of the plurality of pixels by using the photoelectric conversion element;

obtaining a second image signal of each of the plurality of pixels by using the photoelectric conversion element;

obtaining a first value of each of the plurality of pixels from the first image signal and the second image signal;

obtaining a histogram of the first value;

determining a defective pixel by using the histogram;

obtaining a third image signal of each of the plurality of pixels by reading an information of a subject;

correcting the third image signal of the defective pixel.

3. The method of driving a device according to claim 1, wherein the first image signal is obtained while an accumulation time of the photoelectric conversion element is 0, and the second image signal is obtained by reading a calibration sheet.

5. The method of driving a device according to claim 1, wherein the first value is a difference, a sum, a ratio or a product of the first image signal and the second image signal.

7. The method of driving a device according to claim 1, wherein an image of the subject is displayed by using the plurality of pixels.

9. The method of driving a device according to claim 1, wherein the device is formed on a single crystal substrate.

11. The method of driving a device according to claim 1, wherein each of the plurality of pixels further comprises:

a second transistor comprising a second gate electrically connected to the photoelectric conversion element, and one of second source and drain electrically connected to the first transistor; and

a third transistor comprising one of third source and drain electrically connected to the second gate and the photoelectric conversion element.

2. A method of driving a device comprising a plurality of pixels, each comprising a first transistor and a photoelectric conversion element, comprising the steps of:

obtaining a first image signal of each of the plurality of pixels by using the photoelectric conversion element;

obtaining a second image signal of each of the plurality of pixels by using the photoelectric conversion element;

obtaining a first value of each of the plurality of pixels from the first image signal and the second image signal;

obtaining a variance or a standard deviation of the first value;

determining a defective pixel by using the variance or the standard deviation;

obtaining a third image signal of each of the plurality of pixels by reading an information of a subject;

correcting the third image signal of the defective pixel.

4. The method of driving a device according to claim 2, wherein the first image signal is obtained while an accumulation time of the photoelectric conversion element is 0, and the second image signal is obtained by reading a calibration sheet.

6. The method of driving a device according to claim 2, wherein the first value is a difference, a sum, a ratio or a product of the first image signal and the second image signal.

8. The method of driving a device according to claim 2, wherein an image of the subject is displayed by using the plurality of pixels.

10. The method of driving a device according to claim 2, wherein the device is formed on a single crystal substrate.

12. The method of driving a device according to claim 2, wherein each of the plurality of pixels further comprises:

a second transistor comprising a second gate electrically connected to the photoelectric conversion element, and one of second source and drain electrically connected to the first transistor; and

a third transistor comprising one of third source and drain electrically connected to the second gate and the photoelectric conversion element.