Inventor of orthopantomographic machine is:: (A) Hounsfield, (B) Roentgen, (C) Kell, (D) Numata
Answer is D. Paatero and, independently, Numata were the first to describe the principles of panoramic radiography. Figure given shows a schematic view of the relationships between the X-ray source, the patient, the secondary collimator and the image receptor during panoramic image formation.