Patent ID: 9592015
Date: 2017-03-14
CPC Classifications: A61B

Claim:
1. A radiographic apparatus, comprising: an x-ray source configured to emit x-ray; a detecting device configured to detect the x-ray passing through a subject; a collimator configured to restrict the spread of the x-ray emitted from the x-ray source; a collimator activating device configured to activate the collimator to change a degree of opening of the collimator; a visible light source provided on the collimator and configured to emit visible light beams which pass through a space between shielding vanes of the collimator; a visible light source controller configured to control the visible light source; a calculation device configured to calculate an upper limit of the degree of opening based on spread of the x-ray emitted from the x-ray source; and a collimator controller configured to control the collimator activating device so that the spread of the x-ray does not exceed the upper limit of the degree of opening.