Patent · US Expired

Motion picture sound system

US4124784A · kind A · utility

13Cited by
3References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 23, 1977
Grant dateNov 7, 1978
Priority date
Expiry dateMay 23, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B20/00992
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A system for detecting and reproducing variable-area-type optically recorded audio signals by cyclically detecting substantially only the position of a boundary of the sound track. In one embodiment, the boundary is detected by imaging the boundary onto an array of photosensors and scanning the array to provide an output signal containing a transition corresponding in the time domain to the position of the boundary. The transition signal is filtered and sliced to provide electrical interpolation to improve the resolution substantially over the special resolution of the photosensitive elements of the array. The system may also include a multitrack capability with means for minimizing the effect of film weave.

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