Patent · US Expired

Conical blur filter for reducing artifacts in imaging apparatus

US5322998A · kind A · utility

37Cited by
7References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 31, 1993
Grant dateJun 21, 1994
Priority date
Expiry dateMar 31, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B27/46
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optical blur filter having a substantially conical shape is used in imaging apparatus to limit high spatial frequencies incident upon an image sensor, and thereby to reduce undersampling artifacts. By having a conical shape, the filter images a circular blur pattern upon an array of adjacent photosites. A conical shape with a distinct vertex images an annular pattern, and a flattened vertex fills in the central region of the pattern.

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