Concentric exposure sequence for image sensor

• US 8,164,651 B2
• Filed: 04/29/2008
• Issued: 04/24/2012
• Est. Priority Date: 04/29/2008
• Status: Active Grant

• Current Assignee: Omnivision Technologies Incorporated (Will Semiconductor Co., Ltd. Shanghai)
• Original Assignee: Omnivision Technologies Incorporated (Will Semiconductor Co., Ltd. Shanghai)
• Inventors: Hamilton, John F. Jr., Compton, John T., Pillman, Bruce H.
• Primary Examiner(s): Ometz, David
• Assistant Examiner(s): DURNFORD GESZVAIN, DILLON
• Application Number:
  US12/111,219
• Publication Number:
  US 20090268055A1
• Time in Patent Office: 1,456 Days
• Field of Search: 348/229.1, 348/230.1, 348276-280
• US Class Current: 348/229.1
• CPC Class Codes: H04N 23/631 Graphical user interfaces [GUI] specially adapted for controlling image capture or setting capture parameters
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 25/133 including elements passing panchromatic light, e.g. filters passing white light
• CPC Class Codes: H04N 25/135 based on four or more different wavelength filter elements
• CPC Class Codes: H04N 25/46 by combining or binning pixels
• CPC Class Codes: H04N 25/531 by controlling rolling shutters in CMOS SSIS
• CPC Class Codes: H04N 25/534 depending on the spectral component

Abstract

A method for image capture includes providing an image sensor having at least one segmented row of pixels, wherein the at least one segmented row comprises at least first and second disjoint row subsets of pixels, wherein the reset and readout operations for each row subset are controllably independent of each other; timing the exposure interval of the first subset to be photographically centered with the exposure interval of the second subset; and combining the image data obtained from the first and second row subset exposures to form a row of pixel values.

Claims

1. A method for image capture comprising:

(a) providing an image sensor having at least one segmented row of a plurality of rows of pixels, wherein the at least one segmented row comprises at least first and second row subsets of pixels selected from every other pixels of the at least one segmented row, wherein a reset operation of the first row subset is independently controlled with respect to a reset operation of the second row subset, and wherein a readout operation of the first row subset is independently controlled with respect to a readout operation of the second row subset;

(b) timing a first exposure interval of the first row subset to be photographically centered with a second exposure interval of the second row subset, the first exposure interval being different from the second exposure interval; and

(c) combining image data obtained from exposure signals of the first and second row subsets to form a row of pixel values, wherein exposure signals of the plurality of rows of pixels are sequentially read in a row-by-row manner.

2. The method of claim 1 wherein both the first and the second row subsets have color pixels.

3. The method of claim 1 wherein the first row subset has color pixels and the second row subset has panchromatic pixels.

4. The method of claim 1 wherein combining the image data further comprises combining image data obtained from pixels in different rows.

5. The method of claim 1 wherein the at least one segmented row further comprises a third row subset, also disjoint with respect to the first and second row subsets and wherein the exposure interval of the third subset is photographically centered with the exposure intervals of the first and second subsets.

6. A method for image capture comprising:

(a) providing an image sensor having at least one segmented row of a plurality of rows of pixels, wherein the at least one segmented row comprises at least first and second row subsets of pixels selected from every other pixels of the at least one segmented row, wherein each row subset can be separately read and reset;

(b) exposing pixels within the at least one row of pixels by;

(i) resetting the first row subset to begin a first exposure and, after a first interval, resetting the second row subset to begin a second exposure;

(ii) reading the second row subset to end the second exposure and obtain a second exposure signal value and, after a second interval, reading the first row subset to end the first exposure and obtain a first exposure signal value, wherein the durations of the first interval and second interval are configured to be within 20% of the duration of the first exposure; and

(c) combining the image data obtained from the first and second exposure signal values to form a row of pixel values, wherein exposure signal values of the plurality of rows of pixels are sequentially read in a row-by-row manner.

7. The method of claim 6 wherein both the first and the second row subsets have color pixels.

8. The method of claim 6 wherein the first row subset has color pixels and the second row subset has panchromatic pixels.

9. The method of claim 6 wherein combining the image data further comprises combining image data obtained from pixels in different rows.