Radiation imaging system and apparatus and method for detecting defective pixel
AssigneeFUJIFILM Corporation
InventorTakuji Tada
Life of this patent
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Abstract
An X-ray imaging system includes an X-ray source, first and second absorption gratings, and an FPD. The first absorption grating passes X-ray emitted from the X-ray source to form a G1 image. The second absorption grating modulates intensity of the G1 image at each of relative positions to form two or more fringe images. The relative positions differ in phase with respect to a period pattern of the G1 image. The FPD detects two or more frames of image data of the fringe images. A defective pixel detector reads two or more frames of image data stored in a memory and obtains a characteristic value of an intensity modulated signal on a pixel-by-pixel basis based on the read image data. The defective pixel detector detects a defective pixel based on the characteristic value obtained.
Claims16
A defective pixel detection apparatus used in an X-ray radiation imaging system, the X-ray radiation imaging system including a grating, an intensity modulator, and an X-ray radiation image detector, the grating passing X-ray radiation emitted from an X-ray radiation source to form a first fringe image, the intensity modulator modulating intensity of the first fringe image at each of relative positions to form two or more second fringe images, the relative positions differing in phase with respect to a period pattern of the first fringe image, the X-ray radiation image detector detecting the second fringe image, the defective pixel detection apparatus comprising:
- a characteristic value obtaining section for obtaining a characteristic value from an intensity modulated signal on a pixel-by-pixel basis, the intensity modulated signal representing a relation between a relative position and a pixel value;
- and
- a defective pixel detecting section for detecting a defective pixel based on the characteristic value.
A defective pixel detection method used in an X-ray radiation imaging system, the X-ray radiation imaging system including a grating, an intensity modulator, and an X-ray radiation image detector, the grating passing X-ray radiation emitted from an X-ray radiation source to form a first fringe image, the intensity modulator modulating intensity of the first fringe image at each of relative positions to form two or more second fringe images, the relative positions differing in phase with respect to a period pattern of the first fringe image, the X-ray radiation image detector detecting the second fringe image, the defective pixel detection method comprising:
- obtaining a characteristic value from an intensity modulated signal on a pixel-by-pixel basis, the intensity modulated signal representing a relation between a relative position and a pixel value;
- and
- detecting a defective pixel based on the characteristic value.
An X-ray radiation imaging system comprising:
- a grating for passing X-ray radiation emitted from an X-ray radiation source to form a first fringe image;
- an intensity modulator for modulating intensity of the first fringe image at each of relative positions to form two or more second fringe images, the relative positions differing in phase with respect to a period pattern of the first fringe image;
- an X-ray radiation image detector for detecting the second fringe images;
- a characteristic value obtaining section for obtaining a characteristic value from an intensity modulated signal on a pixel-by-pixel basis, the intensity modulated signal representing a relation between a relative position and a pixel value;
- and
- a defective pixel detecting section for detecting a defective pixel based on the characteristic value.
Dependencies are inferred from the claim text.