US 11,686,691 B2
Radiation imaging apparatus, radiation imaging system, and radiation imaging method
Atsushi Iwashita, Tokyo (JP); Kosuke Terui, Yokohama (JP); Katsuro Takenaka, Honjo (JP); and Yoshiaki Ishii, Kawasaki (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on May 27, 2021, as Appl. No. 17/331,974.
Application 17/331,974 is a continuation of application No. 15/791,566, filed on Oct. 24, 2017, granted, now 11,047,808.
Claims priority of application No. 2016-219952 (JP), filed on Nov. 10, 2016.
Prior Publication US 2021/0285896 A1, Sep. 16, 2021
Int. Cl. A61B 6/00 (2006.01); G01N 23/04 (2018.01); H04N 5/32 (2023.01)
CPC G01N 23/04 (2013.01) [A61B 6/4035 (2013.01); A61B 6/4233 (2013.01); A61B 6/4291 (2013.01); A61B 6/4441 (2013.01); A61B 6/481 (2013.01); A61B 6/482 (2013.01); A61B 6/5264 (2013.01); A61B 6/542 (2013.01); H04N 5/32 (2013.01); H04N 5/3205 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A radiation imaging apparatus that obtains a radiation image by an energy subtraction method of obtaining a new image by processing a plurality of images obtained by capturing an object a plurality of times while changing energy of radiation to irradiate the object, the apparatus comprising:
a pixel array that includes a plurality of pixels;
each of the plurality of pixels comprising a conversion element configured to convert radiation into an electrical signal and having a charge accumulation portion configured to accumulate charges generated in accordance with the radiation, a charge-voltage convertor configured to convert the charges into a voltage, and a reset portion configured to reset the charge-voltage convertor, wherein
each of the plurality of pixels is configured to perform an operation of outputting a first signal corresponding to an electrical signal generated by the conversion element in a first period, and an operation of outputting a second signal corresponding to an electrical signal generated by the conversion element in the first period and a second period different from the first period,
each of the first signal and the second signal is generated without destructing charges accumulated in the charge accumulation portion,
radiation having first energy is emitted in the first period, and radiation having second energy different from the first energy is emitted in the second period, and
in each of the plurality of pixels, the first period starts after the charge-voltage convertor is reset, the charge-voltage convertor is not reset during a period that includes the first period and the second period, and the charge-voltage convertor is reset after the second period.