In order to take advantage of the "heel effect", which positioning approach is more proper?
A. The anode side of the tube should be positioned towards the thick part of the patient.
B. The anode side of the tube should be positioned towards the dense part of the patient.
C. Place the part to be studied under the cathode side.
D. Anode side of the tube should be positioned closest to the chest wall of the patient when doing mammography examination.
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The following factors affect image sharpness except______.
A. geometric size of focal spot
B. movement unsharpness
C. projection distortion
D. elecronic nosie
The X-ray intensity is lower on the anode side of the tube due to______.
A. line focus principle
B. heel effect
C. filament temperature
D. anode inclination
The geometric sharpness of an image is affected by____.
A. focal spot. A large focal spot is easy to obtain good radiographic definition
B. source object distance (SOD). A large SOD is easy to blur image.
C. object film distance (OFD). A large OFD is easy to make image blur.
D. none of the above.
About the “Line Focus Principle”, which of the following statement is correct?
A. The effective/nominal focal area is smaller than actual focal area.
B. The effective/nominal focal area determines the tube rating.
C. The effective/nominal focal area is independent on the anode angle.
D. The effective/nominal focus is modelled as a round shape.
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