Radiation imaging apparatus and radiation imaging system

Patent metadata

Field	Value
Publication number	US-2016299239-A1
Application number	US-201615090471-A
Country	US
Kind code	A1
Filing date	Apr 4, 2016
Priority date	Apr 9, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

A radiation imaging apparatus includes a first control line electrically connected to a control electrode of an imaging switching element, a second control line electrically connected to a control electrode of a detection switching element, a signal line electrically connected to a main electrode of the detection switching element, a capacitance line arranged to be capacitively coupled with the signal line, wherein the capacitance line is different from the first control line and the second control line, a driving unit electrically connected to the second control line and the capacitance line and configured to apply a voltage to the detection switching element and the capacitance line, and a control unit configured to control the driving unit to apply, in a case where an on-state or off-state voltage is applied to the detection switching element, a voltage having an opposite polarity to that of the voltage to the capacitance line.

First claim

What is claimed is:

1 . A radiation imaging apparatus comprising:
an imaging pixel configured to acquire a radiation image, wherein the imaging pixel includes an imaging switching element for outputting a signal from an imaging conversion element; a detection pixel configured to detect radiation incidence, wherein the detection pixel includes a detection switching element for outputting a signal from a detection conversion element; a first control line electrically connected to a control electrode of the imaging switching element; a second control line electrically connected to a control electrode of the detection switching element; a signal line electrically connected to a main electrode of the detection switching element; a capacitance line arranged to be capacitively coupled with the signal line, wherein the capacitance line is different from the first control line and the second control line; a driving unit electrically connected to the second control line and the capacitance line and configured to apply a voltage to the detection switching element and the capacitance line; and a control unit configured to control the driving unit to apply, in a case where an on-state or off-state voltage is applied to the detection switching element, a voltage having an opposite polarity to that of the voltage to the capacitance line.

2 . The radiation imaging apparatus according to claim 1 , wherein the control unit controls the driving unit so that a timing at which the on-state or off-state voltage is applied and a timing at which the voltage having the opposite polarity is applied overlap each other.

3 . The radiation imaging apparatus according to claim 1 , wherein the control unit controls the driving unit so that a timing at which the on-state or off-state voltage is applied coincides with a timing at which the voltage having the opposite polarity is applied.

4 . The radiation imaging apparatus according to claim 1 , wherein ½×Cp×Vpp<Cc×ΔVc<2×Cp×Vpp, is satisfied; and
wherein Cgs is a capacitance formed between the second control line and the signal line, ΔVpp is a voltage difference applied to the second control line, Cc is a capacitance of a capacitively coupled portion, and ΔVc is a voltage difference applied to the capacitance line.

5 . The radiation imaging apparatus according to claim 1 , wherein the capacitance line is arranged side by side in the same direction with respect to the control line.

6 . The radiation imaging apparatus according to claim 1 , wherein the capacitance line is arranged so as to overlap the signal line.

7 . The radiation imaging apparatus according to claim 1 , wherein the capacitively coupled portion is arranged outside an imaging region in which the imaging pixel is arranged.

8 . The radiation imaging apparatus according to claim 1 , wherein the capacitively coupled portion is formed in a region overlapping the imaging pixel and/or the detection pixel.

9 . The radiation imaging apparatus according to claim 1 ,
wherein the detection switching element includes a thin film transistor, and wherein the capacitively coupled portion includes a switching element having the same structure as that of the thin film transistor.

10 . The radiation imaging apparatus according to claim 1 , wherein the detection pixel further includes an imaging conversion element and an imaging switching element connected to the imaging conversion element.

11 . A radiation imaging system comprising:
a radiation source configured to generate radiation; and a radiation imaging apparatus, wherein the radiation imaging apparatus comprises:
an imaging pixel configured to acquire a radiation image, wherein the imaging pixel includes an imaging switching element for outputting a signal from an imaging conversion element;
a detection pixel configured to detect radiation incidence, wherein the detection pixel includes a detection switching element for outputting a signal from a detection conversion element;
a first control line electrically connected to a control electrode of the imaging switching element;
a second control line electrically connected to a control electrode of the detection switching element;
a signal line electrically connected to a main electrode of the detection switching element;
a capacitance line, which is different from the first control line and the second control line, arranged to be capacitively coupled with the signal line;
a driving unit electrically connected to the second control line and the capacitance line and configured to apply a voltage to the detection switching element and the capacitance line; and
a control unit configured to control the driving unit to apply, in a case where an on-state or off-state voltage is applied to the detection switching element, a voltage having an opposite polarity to that of the voltage to the capacitance line.

12 . A radiation imaging apparatus comprising:
an imaging pixel configured to acquire a radiation image, wherein the imaging pixel includes an imaging switching element for outputting a signal from an imaging conversion element; a detection pixel configured to detect radiation incidence, wherein the detection pixel includes a detection switching element for outputting a signal from a detection conversion element; a driving unit configured to apply a voltage for controlling an output through the imaging switching element to the imaging switching element via a first control line, and to apply a voltage for controlling an output through the detection switching element to the detection switching element via a second control line; a signal line for transmitting a signal output through the detection switching element; a capacitance line arranged to be capacitively coupled with the signal line, wherein the capacitance line is different from the first control line and the second control line; and a control unit configured to perform control to change, in a case where the driving unit changes a voltage applied to the detection switching element via the second control line, a voltage applied to the capacitance line to have an opposite polarity to that of the changed voltage to suppress a variation of a signal transmitted to the signal line caused by a charge generated on the signal line via a parasitic capacitance between the second control line and the signal line.

13 . A radiation imaging system comprising:
a radiation source configured to generate radiation; and a radiation imaging apparatus, wherein the radiation imaging apparatus comprises:
an imaging pixel configured to acquire a radiation image, wherein the imaging pixel includes an imaging switching element for outputting a signal from an imaging conversion element;
a detection pixel configured to detect radiation incidence, wherein the detection pixel includes a detection switching element for outputting a signal from a detection conversion element;
a driving unit configured to apply a voltage for controlling an output through the imaging switching element to the imaging switching element via a first control line, and to apply a voltage for controlling an output through the detection switching element to the detection switching element via a second control line;
a signal line for transmitting a signal output through the detection switching element;
a capacitance line arranged to be capacitively coupled with the signal line, wherein the capacitance line is different from the first control line and the second control line; and
a control unit configured to perform control to change, in a case where the driving unit changes a voltage applied to the detection switching element via the

Assignees

• Canon Kk

Inventors

• Watanabe Minoru
• Yokoyama Keigo
• Ofuji Masato
• Kawanabe Jun
• Fujiyoshi Kentaro
• Wayama Hiroshi
• Furumoto Kazuya

Classifications

• H04N25/70

  SSIS architectures; Circuits associated therewith · CPC title

• H04N25/78

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

• H04N23/30

  for generating image signals from X-rays · CPC title

• H10F39/8037

  the integrated elements comprising a transistor · CPC title

• H10F39/1898

  Indirect radiation image sensors, e.g. using luminescent members · CPC title