Patent · US Expired

Offset spectra lens system for a two spectra automatic focusing system

US5973846A · kind A · utility

19Cited by
12References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 30, 1998
Grant dateOct 26, 1999
Priority date
Expiry dateNov 30, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/285
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An improved auto-focus system for a digital camera has a lens designed to have the focus of two spectra offset from each other by a predetermined amount. The two offset spectra are used to calculate two focus signals. Once the two focus signals are calculated the correct direction to move the lens system to set the optimum focus can be determined.

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