3887273 is referenced by 59 patents and cites 4 patents.

A system for projecting a speedometer or other instrument reading as a virtual image, focused at infinity, into the field of view of a vehicle operator includes the windshield and a lens system containing a lens that substantially corrects aberrations caused by curvature of the windshield.

Title
Speedometer optical projection system
Application Number
05/383,244
Publication Number
3887273
Application Date
July 27, 1973
Publication Date
June 3, 1975
Inventor
Griffiths David
Agent
Harness Dickey & Pierce
Assignee
Friedemann Conrad J
IPC
G03b 21/28
G03b 21/00
G02B 27/00
G03B 21/20
G02B 27/01
G01P 01/08
G01P 01/00
B60K 37/00
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