04969714 is referenced by 50 patents and cites 18 patents.

Helmet mounted display apparatus for use in aircraft and rotorcraft includes an image source for generating images that are projected into the pilot's forward field of view by a portion of relay optics that are common to both day and night viewing and interchangeable optical eyepieces, one for daytime viewing and one for nighttime viewing.

Title
Helmet mounted display having dual interchangeable optical eyepieces
Application Number
7/313685
Publication Number
4969714
Application Date
February 21, 1989
Publication Date
November 13, 1990
Inventor
William E McLean
Aberdeen
MD, US
Harry R McKinley
Southhampton
MA, US
Harvey A Smith
Hampden
MA, US
Stephen J Smith
Simsbury
CT, US
Joseph T Fournier Jr
Glastonbury
CT, US
Agent
Richard H Kosakowski
Assignee
United Technologies Corporation
CT, US
IPC
G02B 23/12
G02B 27/14
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