Patent · US Expired

Focus inspection device and focusing method

US6795165B2 · kind B2 · utility

8Cited by
3References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 15, 2002
Grant dateSep 21, 2004
Priority date
Expiry dateJul 7, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/28
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A photographic lens and test chart provide for a method of inspecting and adjusting the focus of the lens. The test chart is obliquely inclined relative to a plane perpendicular to the viewing axis of the photographic lens. Test photographs are taken of the test chart under low magnification and high magnifications the test photographs enabling the photographic lens to be adjusted for proper focus.

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