Patent · US Expired

Collapsible spectacles

US4820035A · kind A · utility

18Cited by
3References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 28, 1985
Grant dateApr 11, 1989
Priority date
Expiry dateFeb 28, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02C5/2263
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The invention provides spectacles in which the distance between two lens frames (1)(2) is variable and which has holders (7)(7a) on the lens frame, a bridge (8) slidably fitted in the holder for connecting the lens frames together and holding means (9) for determining the effective length of the bridge.

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