Patent ID: 7876874

Claim:
A radiographing apparatus which comprises: an X-ray source which radiates x-rays with a first energy spectrum and x-rays with a second energy spectrum; an X-ray detector which detects the x-rays with the first energy spectrum and the x-rays with the second energy spectrum transmitted through an object to be examined, and outputs projection data of the first energy spectrum and projection data of the second energy spectrum; a control device which controls operations of the X-ray source and the X-ray detector; an image processing device which generates a desired image on the basis of the projection data of the first energy spectrum and the projection data of the second energy spectrum; and a display device which displays the image, wherein the image processing device comprises: an acquisition device which acquires the projection data of the first energy spectrum and the projection data of the second energy spectrum; a synthetic image generating device which synthesizes a first image on the basis of the projection data of the first energy spectrum and a second image on the basis of the projection data of the second energy spectrum according to a predetermined synthetic condition to generate a synthetic image, wherein the display device displays the generated synthetic image; and a correction device which performs correction according to levels of effective energy of the first energy spectrum and effective energy of the second energy spectrum in order to equalize noise of the first image to noise of the second image for the first image based on projection data of the first energy spectrum and the second image based on projection data of the second energy spectrum, wherein the synthetic image generating device synthesizes the first image and the second image with noise equalized by the correction device.