06142934 is referenced by 42 patents and cites 12 patents.

A retrofocus objective lens system which is conducive for an otoscope includes a first group of optical elements positioned at a distal portion and a second group of optical elements proximally spaced from the first group of optical elements. The first group of optical elements includes at least one negative small diameter lens while the second group of optical elements include a plurality of small diameter lenses having an aggregate optical power which is positive, allowing an image of interest to be transmitted through the system without any intermediate imaging planes, and without the need for rod lenses. The first and second lens groups are retained in a plurality of linearly interconnected lens tubes such that one lens tubes is linearly adjustable in relation to the remaining lens tubes in order to vary the focal length of the lens system.

Title
Objective lens system for imaging instrument
Application Number
52570
Publication Number
6142934
Application Date
December 28, 1998
Publication Date
November 7, 2000
Inventor
Ronald A Hauptli
Warners
NY, US
William M Wrisley
North Syracuse
NY, US
David G Perkins
Syracuse
NY, US
William H Lagerway
Auiburn
NY, US
Agent
Wall Marjama & Bilinski
Assignee
Welch Allyn
NY, US
IPC
A61B 1/227
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