1. Field of the Invention
The present invention relates to a radiation detector and an X-ray computed tomography (CT) apparatus incorporating the radiation detector.
2. Description of the Related Art
X-ray CT apparatus developed hitherto have an X-ray tube and a radiation detector. X-rays generated in the X-ray tube are applied to an object. After passing through the object, the X rays are applied to the radiation detector.
The radiation detector has a plurality of detector modules that are arranged in a substantially circular arc, in the channel direction that intersects at right angles with the axis of an object. Each detector module has a scintillator array and a photodiode array. The scintillator array converts the incident radiation (i.e., X rays) into a light beam. The photodiode array converts the light beam into an electric signal. The electric signals from the respective detector modules are amplified by an amplifier. The signals amplified are converted to a digital signal by a data acquisition system (DAS) unit.
The electric signals from the respective detector modules are supplied to amplifier substrates through a flexible cable. The amplifier substrates amplify the signals, which are supplied to the DAS unit. The DAS unit converts the signals to a digital signal. A connector connects the flexible cable to the amplifier substrates.
Jpn. Pat. Appln. Laid-Open Publication No. 2005-283441 discloses a radiation detector.
Recently, large radiation detectors have been developed. To provide a large radiation detector, detector modules are arranged, forming two columns that lie side by side along the axis of an object (or in the slice direction). The detector modules constituting each column are arranged in the channel direction.
The radiation detector is held in the gantry of an X-ray CT apparatus. If the detector modules are arranged, forming two columns that lie side by side in the slice direction, the depth of the radiation detector will increase.
Since the detector modules are arranged in the deepest section of the housing, the connectors of the detector modules are difficult to remove from, and insert into, the housing during the manufacture or the maintenance work. Consequently, the connector may not be well connected, or much time may be required to remove and insert the connectors. Particularly, when the number of detector modules and amplifier substrates is large, operability is further deteriorated.