Patent · US Expired

Testing and calibrating device for optical eye length measurement instruments

US6481847B1 · kind B1 · utility

1Cited by

2References

12Claims

0Family size

Assignee

Carl Zeiss Jena GmbH · DE

Inventors

Roland Bergner · Jena, DE
Lothar Mueller · Ottendorf, DE

Key dates

Filing date	Aug 3, 2000
Grant date	Nov 19, 2002
Priority date	—
Expiry date	Dec 27, 2020

Classification

Technology area (CPC A)Human Necessities
CPC primaryA61B3/1005
WIPO fieldMedical technology
WIPO sectorInstruments

Abstract

A testing and calibrating device for optical eye length measurement devices comprising two plano-convex lenses which are arranged in the illumination beam path so as to be oppositely oriented. A neutral filter with a defined transmission is located between these two plano-convex lenses.

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