Solid-state image sensor for capturing high-speed phenomena and drive method for the same

Patent metadata

Field	Value
Publication number	US-9420210-B2
Application number	US-99696909-A
Country	US
Kind code	B2
Filing date	Jun 10, 2009
Priority date	Jun 10, 2008
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A burst reading memory section ( 200 ) and continuous reading memory section ( 210 ) are independently provided for each of the two-dimensionally arrayed pixels ( 10 ). The burst reading memory section ( 200 ) has capacitors ( 25001 - 25104 ) capable of holding a plurality of signals. The continuous reading memory section ( 210 ) has only one capacitor 213 . Signal output lines for the two memory sections are separately provided. When a signal produced by photoelectric conversion at the pixel ( 10 ) is outputted on a pixel output line ( 14 ), the signal can be simultaneously written in the capacitors at both memory sections ( 200, 201 ), after which the signals can be separately extracted to the outside at different timings. Therefore, a series of images taken at extremely short intervals of time during a short period of time can be obtained at an arbitrary timing without impeding a continuous image-acquiring operation at a low frame rate. Accordingly, both an ultrahigh-speed imaging operation having a limitation on the number of frames and an imaging that is rather slow but has no limitation on the number of frames can be simultaneously performed.

First claim

The invention claimed is:

1. A solid-state image sensor, comprising:
a pixel area in which a plurality of pixels each including a photoelectric conversion section for receiving light and producing photocharges are arranged in a two-dimensional array; and
a memory area, which is an area separated from the pixel area and in which a burst reading memory section and continuous reading memory section are arranged for each pixel,
the burst reading memory section having memory sections such that each pixel is connected to its own plurality of memory sections in the burst reading memory section, the plurality of the memory sections being provided to hold output signals of one pixel in the pixel area for a plurality of frames without being read to an outside of the memory area, and
separately from the burst reading memory section, the continuous reading memory section having memory sections such that each pixel is connected to its own one memory section in the continuous reading memory section, and
in which an output signal line for reading signals held in the burst reading memory section and an output signal line for reading a signal held in the continuous reading memory section are independently provided.

2. The solid-state image sensor according to claim 1 , wherein each pixel further includes:
a transfer element for transferring photocharges produced in the photoelectric conversion section to a detection node for converting an electric-charge signal to a voltage signal;
a buffer element for sending an output signal from the detection node to a pixel output line; and
a reset element for resetting at least the photoelectric conversion section and the detection node.

3. A solid-state image sensor comprising:
a pixel area in which a plurality of pixels each including a photoelectric conversion section for receiving light and producing photocharges are arranged in a two-dimensional array;
a memory area, which is an area separated from the pixel area and in which a burst reading memory section and continuous reading memory section are arranged for each pixel, the burst reading memory section including a plurality of memory sections for each pixel so that output signals of one pixel in the pixel area can be held for a plurality of frames without being read to the outside, and the continuous reading memory section including each one memory section for each pixel separately from the burst reading memory section, and in which an output signal line for reading signals held in the burst reading memory section and an output signal line for reading a signal held in the continuous reading memory section are independently provided; and
a drive control section for driving the pixels, the burst reading memory sections and the continuous reading memory sections and for performing:
a first drive mode, in which an operation of accumulating photocharges in each pixel and an operation of holding a signal read from each pixel in each corresponding continuous reading memory section are performed simultaneously at all the pixels and, subsequently, the signals corresponding to one frame are outputted by sequentially reading the signals held in the continuous reading memory sections; and
a second drive mode, in which the operation of accumulating photocharges in each pixel and an operation of holding a signal read from each pixel in one of said plurality of memory sections of each corresponding burst reading memory section are performed simultaneously at all the pixels and repeated while changing the memory section to hold the signal read from each pixel from one to another among said plurality of memory sections in each burst reading memory section sequentially, and after the signals corresponding to a plurality of frames are held in the burst reading memory sections, the signals corresponding to the plurality of frames are outputted by sequentially reading signals from the burst reading memory sections.

4. The solid-state image sensor according to claim 3 , wherein the drive control section concurrently performs both the first drive mode and the second drive mode so as to simultaneously hold each signal read from each pixel in one of said plurality of memory sections of each corresponding burst reading memory section as well as in each corresponding continuous reading memory section.

5. A method for driving the solid-state image sensor comprising:
providing a pixel area in which a plurality of pixels each including a photoelectric conversion section for receiving light and producing photocharges are arranged in a two-dimensional array;
providing a memory area, which is an area separated from the pixel area and in which a burst reading memory section and continuous reading memory section are arranged for each pixel, the burst reading memory section including a plurality of memory sections for each pixel so that output signals of one pixel in the pixel area can be held for a plurality of frames without being read to the outside, and the continuous reading memory section including each one memory section for each pixel separately from the burst reading memory section, and in which an output signal line for reading signals held in the burst reading memory section and an output signal line for reading a signal held in the continuous reading memory section are independently provided;
providing a first drive mode, in which an operation of accumulating photocharges in each pixel and an operation of holding a signal read from each pixel in each corresponding continuous reading memory section are performed simultaneously at all the pixels and, subsequently, the signals corresponding to one frame are outputted by sequentially reading the signals held in the continuous reading memory sections; and
providing a second drive mode, in which the operation of accumulating photocharges in each pixel and an operation of holding a signal read from each pixel in one of said plurality of memory sections of each corresponding burst reading memory section are performed simultaneously at all the pixels and repeated while changing the memory section to hold the signal read from each pixel from one to another among said plurality of memory sections in each burst reading memory section sequentially, and after the signals corresponding to a plurality of frames are held in the burst reading memory sections, the signals corresponding to the plurality of frames are outputted by sequentially reading signals from the burst reading memory sections, and the method including concurrently performing both the first drive mode and the second drive mode so as to simultaneously hold each signal read from each pixel in one of said plurality of memory sections of each corresponding burst reading memory section as well as in each corresponding continuous reading memory section.

6. The method for driving a solid-state image sensor according to claim 5 , comprising operating the solid-state image sensor in the first drive mode, generating a trigger signal upon capturing an occurrence of a phenomenon of interest or a change in an object based on a signal generated by the solid-state image sensor, and changing the drive mode according to the trigger signal so as to concurrently perform the first drive mode and the second drive mode.

7. The solid-state image sensor according to claim 2 , further comprising a drive control section for driving the pixels, the burst reading memory sections and the continuous reading memory sections and for performing:
a first drive mode, in which an operation of accumulating photocharges in each pixel and an operation of holding a signal read from each pixel in each corresponding continuous reading memory section are performed simultaneously at all the pixels and, subsequently, the signals corresponding to one frame are outp

Assignees

• Sugawa Shigetoshi
• Kondo Yasushi
• Tominaga Hideki
• Univ Tohoku
• Shimadzu Corp

Inventors

• Sugawa Shigetoshi
• Kondo Yasushi
• Tominaga Hideki

Classifications

• H04N25/771 Primary

  comprising storage means other than floating diffusion · CPC title

• H04N25/616

  involving a correlated sampling function, e.g. correlated double sampling [CDS] or triple sampling · CPC title

• H04N25/78

  Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters · CPC title

• H10F39/1534

  Interline transfer · CPC title

• H01L27/14843

  Electricity · mapped topic