05774271 is referenced by 26 patents and cites 18 patents.

A lamp assembly includes a condensing lens group disposed at one end for collecting and collimating a light from a light source, an exit lens group at the other end of the assembly, including at least one objective lens element for projecting an illuminated light spot at a predetermined distance, and an iris disposed between the condenser lens group and the exit lens group having a variable opening for varying the size of the illuminated light spot between a minimum and a maximum spot diameter at the predetermined distance. The invention allows the illuminated light spot to be focused for at least two separate iris positions at the predetermined distance by allowing relative movement between the objective lens element and the iris to provide enhanced edge definition and illumination uniformity.

Title
Lamp assembly
Application Number
8/681894
Publication Number
5774271
Application Date
July 29, 1996
Publication Date
June 30, 1998
Inventor
Steven R Slawson
Auburn
NY, US
Jeffrey Perkins
Tully
NY, US
William H Lagerway
Auburn
NY, US
Agent
Wall Marjama & Bilinski
Assignee
Welch Allyn
NY, US
IPC
F21V 7/04
G02B 3/00
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