Patent · US Expired

Focus detecting device including means for determining a priority of correlation calculations

US4766302A · kind A · utility

31Cited by
12References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 17, 1985
Grant dateAug 23, 1988
Priority date
Expiry dateMay 17, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/34
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In a focus detection system for detecting focus condition of an objective lens, there is disposed a pair of photo sensor arrays each having a plurality of photo cells lined up in one direction to receive a first image and second image passed through respectively a lens system and the photo sensor arrays produce first original signal groups and second original signal groups each signal groups corresponding to light intensity of the images projected thereto. A processing device processes the original signal groups in such a manner that the first original signal groups are respectively divided into a plurality of blocks, and one of the blocks of the first original signal groups is selected and it is detected that in what group in the selected block best coincidence occurs.

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