04081209 is referenced by 66 patents and cites 3 patents.

Headgear incorporating an optical display system comprising, an optical data source mounted within the headgear above the level of the wearer's eyes, an image combiner having a spherical reflecting surface directed inwardly of the helmet and intercepting the wearer's forward line-of-sight, and a prism positioned and dimensioned so that a collimated, aberration free virtual image of the data source is presented to the wearer as a result of reflection of rays transmitted from the data source by way of the prism to the spherical reflector. Such aberration as is introduced by the prism compensates for aberration introduced by the spherical reflector.

Title
Headgear with spherical semi-reflecting surface
Application Number
5/680746
Publication Number
4081209
Application Date
April 27, 1976
Publication Date
March 28, 1978
Inventor
Stafford Malcolm Ellis
Maidstone
EN
Fritz Peter Heller
Bromley
EN
Agent
Kirschstein Kirschstein Ottinger Frank & Cobrin
Assignee
Elliott Brothers
EN
IPC
G02B 27/14
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