05515186 is referenced by 52 patents and cites 41 patents.

A welding helmet and lens therefor includes a shield and a lens including a two identical optical components, each including a polarizer, a further polarizer (analyzer) optically between said optical components and effectively shared as an output device from one optical component and an input device for the other optical component, the transmissive axes of respective polarizers of said optical components being operatively oriented relative to one another to improve extinction of light incident on said lens at prescribed angles. The lens may be used in other optical systems. A method of making a light transmission controlling optical system employing two optical components control device, includes assembling a plurality of identical optical components, each having substantially identical alignment characteristics, positioning at least two of the optical components in optical series such that at least one optical component is facing in a direction opposite the facing direction of the other optical component, whereby the polar alignment of at least one part of both of said optical components is equi-angular and opposite sense relative to a reference direction.

Title
Eye protection device for welding helmets which reduces obliquely incident light
Application Number
814380
Publication Number
5515186
Application Date
July 9, 1993
Publication Date
May 7, 1996
Inventor
John D Fergason
Mountanview
CA, US
James L Fergason
Atherton
CA, US
Arthur L Berman
San Jose
CA, US
Jeffrey K Fergason
Menlo Park
CA, US
Agent
Renner Otto Boisselle & Sklar
Assignee
OSD Envizion Company
CA, US
IPC
G02F 1/1335
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