X-ray inspection device and calibration method thereof

An X-ray inspection device comprising:

• an X-ray generation source that irradiates an inspection region with an X-ray;
• an X-ray detector that detects the X-ray passing through the inspection region;
• a display unit that displays various types of information;
• and
• an input/output unit that is connectable to an external device,
• wherein the X-ray detector includes
• an X-ray detection element that outputs a pulse signal with a peak value corresponding to an energy of the X-ray passing through the inspection region,
• an X-ray detection unit consisting of a plurality of pixels that detect the number of the pulse signals exceeding a predetermined threshold voltage, among the pulse signals output from the X-ray detection element, and
• a control parameter control unit that performs control of changing a value of a control parameter to cause the number of the pulse signals exceeding the threshold voltage to change, and
• the external device includes
• a storage unit that stores, for each pixel, a correspondence relationship between the value of the control parameter controlled by the control parameter control unit and the number of the pulse signals detected by respective pixels, which is input via the input/output unit, and
• an abnormal pixel information output unit that generates abnormal pixel information to specify an abnormal pixel, based on the correspondence relationship between the value of the control parameter and the number of the pulse signals detected by respective pixels, the correspondence relationship being read out from the storage unit, and outputs the abnormal pixel information to the display unit via the input/output unit.

A calibration method of an X-ray inspection device including an X-ray generation source that irradiates an inspection region with an X-ray, and

• an X-ray detector that detects the X-ray passing through the inspection region, the X-ray detector including an X-ray detection element that outputs a pulse signal with a peak value corresponding to an energy of the X-ray passing through the inspection region and an X-ray detection unit consisting of a plurality of pixels that detect the number of the pulse signals exceeding a predetermined threshold voltage, among the pulse signals output from the X-ray detection element, the calibration method comprising:
• a step of irradiating the inspection region with the X-ray;
• an X-ray detection step of detecting the X-ray passing through the inspection region;
• a storage step of storing, for each pixel, a correspondence relationship between a value of a control parameter to cause the number of the pulse signals exceeding the threshold voltage to change and the number of the pulse signals detected by respective pixels, in a storage unit;
• and
• an abnormal pixel information output step of outputting abnormal pixel information to specify an abnormal pixel based on the correspondence relationship between the value of the control parameter and the number of the pulse signals detected by respective pixels, the correspondence relationship being read out from the storage unit.

A calibration method of an X-ray inspection device including an X-ray generation source that irradiates an inspection region with an X-ray, and

• an X-ray detector that detects the X-ray passing through the inspection region, in which the X-ray detector includes
• an X-ray detection element that outputs a pulse signal with a peak value corresponding to an energy of the X-ray passing through the inspection region, and
• an X-ray detection unit consisting of a plurality of pixels that detect the number of the pulse signals exceeding a predetermined threshold voltage, among the pulse signals output from the X-ray detection element, the calibration method comprising:
• a step of setting up a radiation quality variable body having a known absorption edge in the inspection region;
• a step of irradiating the inspection region with the X-ray;
• an X-ray detection step of detecting the X-ray passing through the inspection region;
• a storage step of storing, for each pixel, a correspondence relationship between a value of a control parameter to cause the number of the pulse signals exceeding the threshold voltage to change and the number of the pulse signals detected by respective pixels, in a storage unit;
• a control parameter value specifying step of specifying, for each pixel, the threshold voltage at which an inclination of the number of the pulse signals detected by respective pixels, which is read out from the storage unit, with respect to the control parameter changes discontinuously;
• and
• a calibration information output step of outputting the threshold voltage specified in the control parameter value specifying step in association with the known absorption edge, as calibration information for respective pixels.