Patent · US Expired

Radiography apparatus

US4464777A · kind A · utility

5Cited by
2References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 16, 1981
Grant dateAug 7, 1984
Priority date
Expiry dateOct 16, 2001

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B6/589
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Disclosed is a radiography apparatus comprising an X-ray tube for radiating X-ray beam in a fan shape, a detector for detecting the X-ray beam coming through a living body at a plurality of angular components of the X-ray beam, and a sampling circuit for sampling an output signal of the detector when the living body moves at a given speed in a direction orthogonal to the plane of the X-ray beam, whereby a radiogram is formed by using the output signal of the sampling circuit. In the radiography apparatus, the distance between the living body and the X-ray tube is variable and is detected by a potentiometer interlocked with the movement of the living body. A pulse signal at a frequency corresponding to an output level of the potentiometer is produced by a pulse frequency modulation circuit, and is supplied as a timing signal to the sampling circuit. Thus, a sampling frequency of the sampling circuit is determined by the distance between the X-ray tube 10 and the living body, so that a radiogram with the same enlargement factor in the X and Y directions is obtained.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.