Patent · US Expired

Framing tube and framing camera

US4467189A · kind A · utility

52Cited by
2References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 2, 1981
Grant dateAug 21, 1984
Priority date
Expiry dateOct 2, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J31/502
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A framing tube includes a cylindrical airtight vacuum tube, a shutter plate, and a ramp generator. The container has a photocathode at one end thereof and a fluorescent screen at the other end thereof which is opposite to the photocathode. The shutter plate is disposed between and parallel to the surface of the photocathode and fluorescent screen and has a multiplicity of through holes perforated perpendicular to its surface. The shutter plate also carries at least three electrodes that are disposed perpendicular to the axis of the through holes and spaced parallel to each other. The electrodes divide the surface of the shutter plate into a plurality of sections. The ramp generator is connected to the electrodes. The ramp voltage generated changes in such a manner as to reverse its polarity, producing a time lag between the individual electrode. Developing an electric field across the axis of the through holes in the shutter screen, the ramp voltage controls the passage of the electron beams from the photocathode through the through holes. A framing camera includes the above-described framing tube and an optical system. The optical system includes a semitransparent mirror that brea…

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