Patent · US Expired

Automatic focus position adjusting unit for use in shadowless lighting device

US5068767A · kind A · utility

15Cited by
3References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 21, 1990
Grant dateNov 26, 1991
Priority date
Expiry dateDec 21, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S362/804
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An automatic focus position adjusting unit for use in a shadowless lighting device for medical purposes includes a sensor, a start switch, a start processor, and a direction adjuster. The unit also includes a focus mover, a peak detector, and an adjustment completion unit. The shadowless lighting device for medical purposes has a housing, illuminating bulbs arranged in the housing, and a drive system for inclining the illuminating bulbs so that the optical axes of the illuminating bulbs may converge, and form a focus, on a predetermined position along a focus moving axis. The automatic focus position adjusting unit permits, with a simple operation, an accurate focus position adjustment at a desired position. This is because it is possible to move the focus to a position at which the amount of light, reflected from the predetermined region at the center of the range of light, becomes a maximum.

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