US 7,573,037 B1
Radiation image pickup apparatus, its control method, and radiation image pickup system
Toshio Kameshima, Kumagaya (Japan); Chiori Mochizuki, Sagamihara (Japan); Tadao Endo, Honjo (Japan); Tomoyuki Yagi, Honjo (Japan); and Katsuro Takenaka, Kodama-gun (Japan)
Assigned to Canon Kabushiki Kaisha, Tokyo (Japan)
Filed on Aug. 08, 2006, as Appl. No. 11/500,323.
Claims priority of application No. 2005-236038 (JP), filed on Aug. 16, 2005.
Int. Cl. G01T 1/00 (2006.01)
U.S. Cl. 250—370.09 13 Claims
OG exemplary drawing
 
1. A radiation image pickup apparatus comprising:
a sensor array constructed by two-dimensionally arranging a plurality of pixels each having a conversion element for converting radiation into an electric signal and a transfer switching element for transferring said electric signal from said conversion element;
a plurality of signal wirings each adapted to connect a transfer switching element of said transfer switching elements of said plurality of pixels of said sensor array in a column direction;
a reading circuit unit including a plurality of amplifiers provided in correspondence to said plurality of signal wirings, each of which amplifies an electric signal transferred from a transfer switching element of said transfer switching elements, and reads out an amplified signal;
a switching unit adapted to switch electrical connections among said plurality of signal wirings and an electrical connection between a predetermined one of said plurality of signal wirings and an amplifier corresponding thereto, wherein said switching unit is arranged in front of said amplifier, and said switching unit switches between a first state where said plurality of signal wirings are electrically connected and said predetermined signal wiring and said amplifier corresponding thereto are electrically disconnected and a second state where said plurality of signal wirings are electrically disconnected and said predetermined signal wiring and said amplifier corresponding thereto are electrically connected;
a mode setting unit adapted to set a mode in said radiation image pickup apparatus by switching between a normal reading mode in which an electric signal from one pixel is read out by a corresponding amplifier and a pixel binning mode in which electric signals from a set of pixels are added and an added signal is read out by one of said plurality of amplifiers corresponding to said set of pixels; and
a control unit adapted to control said switching unit to switch between said first state and said second state in accordance with said mode set by said mode setting unit, and adapted to change a dynamic range of said amplifier, such that the dynamic range of said amplifier in the pixel binning mode is larger than the dynamic range of said amplifier in the normal reading mode.