Image capturing apparatus and method of controlling the same, and storage medium
AssigneeCanon Kabushiki Kaisha
InventorShunichi Wakashima
Life of this patent
Estimating the term…
Abstract
An image capturing apparatus includes a pixel array, an AD converter, an output line configured to connect the pixel and the AD converter, a reset unit configured to reset the output line, an amplification transistor configured to amplify a signal from the pixel, a connection unit configured to connect a source of the amplification transistor to the output line, a constant current source, and a control unit configured to, after a voltage of the output line is reset, cause a constant current to flow to the output line and to control to connect a source of the amplification transistor to the output line, wherein the control unit sets a value of the constant current so that the constant current is a lower value than a current required to drive the output line.
Claims13
An image capturing apparatus comprising:
- a pixel array in which a plurality of pixels are arranged in a form of a two-dimensional array;
- an AD converter configured to AD-convert a voltage;
- an output line configured to connect the pixel and the AD converter;
- a reset circuit configured to reset a voltage of the output line;
- an amplification transistor configured to amplify a signal from a charge-voltage converter of the pixel;
- a connection circuit configured to connect a source of the amplification transistor to the output line;
- a constant current source configured to supply a constant current to the output line;
- and
- a controller configured to, after a voltage of the output line is reset by the reset circuit, cause a constant current to flow to the output line by the constant current source and to control to connect a source of the amplification transistor to the output line,
- wherein the controller sets a value of the constant current so that a current value of the constant current is a lower value than a current value required to drive the output line.
A method for controlling an image capturing apparatus having a pixel array in which a plurality of pixels are arranged in a form of a two-dimensional array, an AD converter configured to AD-convert a voltage, an output line configured to connect the pixel and the AD converter, a reset circuit configured to reset a voltage of the output line, an amplification transistor configured to amplify a signal from a charge-voltage converter of the pixel, a connection circuit configured to connect a source of the amplification transistor to the output line, and a constant current source configured to supply a constant current to the output line, the method comprising:
- controlling to cause a constant current to flow to the output line by the constant current source and to connect a source of the amplification transistor in the output line after a voltage of the output line is reset by the reset circuit, wherein in the controlling, a value of the constant current is set so that a current value of the constant current is a lower value than a current value required to drive the output line.
A non-transitory computer-readable storage medium on which is stored a program for causing a computer to execute each step of a method for controlling an image capturing apparatus having a pixel array in which a plurality of pixels are arranged in a form of a two-dimensional array, an AD converter configured to AD-convert a voltage, an output line configured to connect the pixel and the AD converter, a reset circuit configured to reset a voltage of the output line, an amplification transistor configured to amplify a signal from a charge-voltage converter of the pixel, a connection circuit configured to connect a source of the amplification transistor to the output line, and a constant current source configured to supply a constant current to the output line, the method comprising:
- controlling to cause a constant current to flow to the output line by the constant current source and to connect a source of the amplification transistor to the output line after a voltage of the output line is reset by the reset circuit, wherein
- in the controlling, a value of the constant current is set so that a current value of the constant current is a lower value than a current value required to drive the output line.
Dependencies are inferred from the claim text.