Eye protection device for welding helmets which reduces obliquely incident light

Eye protection gear, comprising:

• a light transmission control, and
• mounting means for mounting said light transmission control proximate the eyes of a wearer,
• said light transmission control comprising:
• polarizer means for controlling light transmission, including a polarizer and an analyzer operatively related and positioned relative to each other to control transmission of light therethrough, the light transmission appearing in a field of view relative to said polarizer means as having relatively more transmissive and less transmissive areas;
• and
• further polarizer means cooperative with said polarizer means for increasing the total amount of area in the field of view having relatively dark light transmission characteristic for light incident from a generally oblique horizontal direction.

A light transmission controlling device, comprising

• three optical polarizers in optical series, each polarizer having a first side for receiving incident light and a second side,
• two of said polarizers being substantially identical having at least one similarly shaped physical wall (edge) and a transmissive axis oriented in the same direction relative to said physical wall,
• selectively operable switching means for changing the plane of polarization of light received from one of said polarizers and directing such light to another of said polarizers, and
• said two of said polarizers being relatively positioned with said physical walls thereof aligned in parallel overlying relation and said second surface of one polarizer facing said first surface of another polarizer whereby the direction of the transmissive axis of one polarizer is different from the direction of the transmissive axis of the other polarizer,
• said switching means comprising two substantially identical variable optical retardation liquid crystal cells, each having a first side for receiving incident light and a second side, each having a physical wall (edge) aligned in parallel with the other and a rub alignment direction that is substantially the same relative to said physical wall thereof, said two liquid crystal cells being relatively positioned with said physical walls thereof aligned in parallel overlying relation and said second surface of one liquid crystal cell facing said first surface of the other liquid crystal cell whereby the rub alignment direction of one liquid crystal cell is different from the rub alignment direction of the other liquid crystal cell.

An eye protection device for reducing the transmission of obliquely incident light to the eyes of a user, comprising

• a first polarizer and a first analyzer in optical series having transmissive axes oriented substantially operationally orthogonal to one another;
• a second polarizer and a second analyzer in optical series having transmissive axes oriented substantially operationally orthogonal to one another;
• said second polarizer and said first analyzer being in optical series and having their transmissive axes oriented relative to one another to reduce leakage of obliquely incident light;
• and
• means for positioning said first and second polarizers and said first and second analyzers in proximity to the eyes of a viewer.

An eye protection device positionable in proximity to the eyes of a viewer for reducing transmission leakage of light obliquely incident to the eyes of a user, comprising

• a first polarizer and a first analyzer in optical series having transmissive axes oriented substantially operationally orthogonal to one another;
• a second polarizer in optical series with said first polarizer and said first analyzer and having a transmissive axis operationally oriented at an angle other than parallel to the transmissive axes of said first polarizer and said first analyzer for cooperatively reducing leakage of obliquely incident light;
• and
• means for positioning said first and second polarizers and said first analyzer in proximity to the eyes of a viewer.