IMAGE PICKUP DEVICE

• US 20080252765A1
• Filed: 04/10/2008
• Published: 10/16/2008
• Est. Priority Date: 04/10/2007
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Corporation
• Inventors: Ito, Hiroshi
• Granted Patent: US 8,018,512 B2
• Time in Patent Office: Days
• US Class Current: 348/308
• CPC Class Codes: H04N 25/531 by controlling rolling shutters in CMOS SSIS
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors

Abstract

The present invention resides in an image pickup device capable of reducing the deformation of the image of the photographed object. An image pickup element included in the image pickup device has a matrix of pixels, for which the control of the charge storage and the readout of image signal data is performed on a row-by-row or column-by-column basis. The storage controller controls the charge storage operation of the image pickup element. On the other hand, the readout controller controls the readout of the image signal data from the image pickup element, while keeping constant the unit period for the readout of the image signal data from the image pickup element. A synchronization signal generator provides a synchronization signal as a timing reference for the frame-based operation of the image pickup element. The synchronization signal period controller variably controls the repetition period of the synchronization signal, while the photographing is under way.

Claims

1. An image pickup device comprising:

an image pickup element having a matrix of pixels with their charge storage and image signal readout controlled on a row-by-row or a column-by-column basis;

a storage controller for controlling the charge storage by the image pickup element;

a readout controller for controlling the readout of the image signal from the image pickup element;

a synchronization signal generator for generating synchronization signals as reference for the timing of the frame-based operation of the image pickup element; and

a synchronization signal period controller for variably controlling the repetition period of the synchronization signal while the photographing is under way;

wherein the readout controller keeps constant the unit period in which the image signal data is read out from the image pickup element.

2. An image pickup device as claimed in claim 1, wherein the storage controller keeps constant the unit time for the charge storage performed by the image pickup element.

3. An image pickup device as claimed in claim 1, wherein the storage controller performs the control such that the charge storage for the next frame is started only after the control for the start of the charge storage for the current frame has been completed.

4. An image pickup device as claimed in claim 1, wherein the readout controller performs the control such that the image signal readout for the next frame is started only after the control for the start of the image signal readout for the current frame has been completed.

5. An image pickup device as claimed in claim 1, further comprising a combined frame signal producing member adapted to combine image signals obtained from at least two consecutive frames into one combined frame signal, wherein the combined frame signal producing member is adapted to combine the image signal of each of the frames with certain weighting factors applied depending on the length of the unit time for the charge storage at the image pickup element and on the length of the repetition period of the synchronization signal.

6. An image pickup device as claimed in claim 1, further comprising a combined frame signal producing member adapted to combine image signals obtained from at least two consecutive frames into one frame signal, wherein the vacant period between every two neighboring frames is controlled in such a manner that p+1 or more frame-long section of the image signal may be read out within a p frame-long period (p is an integer equal to or greater than unity) defined by the repetition period of the synchronization signal.