Eye protection device for welding helmets which reduces obliquely incident light

• US 5,515,186 A
• Filed: 07/09/1993
• Issued: 05/07/1996
• Est. Priority Date: 12/26/1991
• Status: Expired due to Term

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Osd Envizion Company
• Inventors: Fergason, John D., Fergason, James L., Fergason, Jeffrey K., Berman, Arthur L.
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): TRICE, RONALD
• Application Number:
  US08/089,265
• Time in Patent Office: 1,033 Days
• Field of Search: 359/53, 359/63, 359/73
• US Class Current: 349/14
• CPC Class Codes: A61F 9/062 with movable polarising filter discs
• CPC Class Codes: G02B 27/28 for polarising used in stereoscopes G02B30/25
• CPC Class Codes: G02F 1/133531 characterised by the arrangement of polariser or analyser axes
• CPC Class Codes: G02F 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence

Abstract

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.

Claims

1. A light transmission control, comprising:

polarizer means including a first polarizer and an analyzer in optical-series having transmissive axes operationally oriented to cooperatively control light transmission through said polarizer means to provide in at least one field of view a relatively dark area and a relatively less dark area, and

further polarizer means including a further polarizer having a transmissive axis operationally oriented at an angle other than parallel to the transmissive axes of said first polarizer and analyzer for cooperating with said polarizer means to darken at least part of said relatively less dark area within said at least one field of view.

2. The control of claim 1, said first polarizer and analyzer having transmissive axes oriented substantially operationally orthogonal to one another.

3. The control of claim 1, said further polarizer means further comprising a further analyzer having a transmissive axis oriented operationally at an angle other than parallel to the transmissive axis of said further polarizer.

4. The control of claim 1, further comprising switching means optically in series with said first polarizer and said analyzer for switching the effective optical relation of the transmissive axes of said polarizer and said analyzer selectively to change light transmission through said polarizer means.

5. The control of claim 4, said switching means comprising a liquid crystal cell.

6. The control of claim 5, said liquid crystal cell comprising a liquid crystal cell that affects light based on the principle of variable optical retardation.

7. The control of claim 4, further comprising further switching means optically in series with said analyzer and said further polarizer for switching the effective optical relation of the transmissive axes of said analyzer and said further polarizer selectively to change light transmission through said further polarizing means.

8. The control of claim 7, said further switching means comprising a liquid crystal cell.

9. The control of claim 8, said liquid crystal cell comprising a liquid crystal cell that affects light based on the principle of variable optical retardation.

10. The control of claim 4, said switching means being operative according to the principle of variable optical retardation, said first polarizer, analyzer and switching means being related such that in respective optically functional modes of said switching means relatively less and relatively more light is transmitted by said analyzer.

11. The control of claim 4, further comprising means for adjusting the quadrature components of light transmitted relative to said switching means.

12. The control of claim 11, said means for adjusting comprising a quarter wave plate.

13. The control of claim 7, said switching means and said further switching means each comprising a respective variable optical retardation liquid crystal cell.

14. The control of claim 7, wherein the polar directions of alignment of the transmissive axis of said polarizer and said further polarizer are substantially equi-angularly spaced and on opposite sides of a reference direction.

15. The control of claim 1, wherein the operative orientations of the transmissive axes of respective polarizer and further polarizer are substantially equi-angularly spaced relative to and on opposite sides of a reference direction.

16. Eye protection gear, comprising the light transmission control of claim 1, and mounting means for mounting said light transmission control for eye protection.

17. The gear of claim 16, said mounting means comprising a shield for protecting at least part of the face of a person.

18. The gear of claim 16, said polarizer means being positioned in said mounting means to be located relative to an eye to provide a primary area of substantially minimum light transmission over a generally linear direction that is near but is not horizontal relative to the eye, and said further polarizer means is positioned relative to said polarizer means and located relative to an eye to provide a primary area of substantially minimum light transmission over a different generally linear direction that is near but is not horizontal relative to the eye.

19. A light transmission control, comprising:

polarizer means including a first polarizer and an analyzer in optical series having transmissive axes operationally oriented to cooperatively control light transmission through said polarizer means to provide in at least one field of view a relatively dark area and a relatively less dark area, and

further polarizer means including a further polarizer having a transmissive axis operationally oriented at an angle other than parallel to the transmissive axes of said first polarizer and analyzer for cooperating with said polarizer means to darken at least part of said relatively less dark area within said at least one field of view,

said polarizer means and said further polarizer means each comprising switching means optically in series with said first polarizer and said further polarizer, respectively, each switching means including a liquid crystal cell for switching the effective optical relation of the transmissive axes of said polarizer and said analyzer selectively to change light transmission through said polarizer means and wherein the polar directions of rub or other alignment of said respective liquid crystal cells are substantially equi-angularly spaced and on opposite sides of a reference direction.

20. The control of claim 19, wherein the polar directions of alignment of the transmissive axis of said polarizer and said further polarizer are substantially equi-angularly spaced and on opposite sides of said reference direction.

21. The control of claim 20, further comprising means for adjusting the quadrature components of light transmitted relative to said switching means and further means for adjusting the quadrature components of light transmitted relative to said further switching means.

22. The control of claim 21, said means for adjusting and said further means for adjusting comprising a respective quarter wave plate.

23. The control of claim 21, wherein said means for adjusting and further means for adjusting have respective slow and fast axes, and wherein the polar alignment directions of the respective slow and fast axes of said means for adjusting relative to the respective slow and fast axes of said further means for adjusting are substantially equi-angularly spaced and on opposite sides of said reference direction.

24. The control of claim 23, wherein said polarizer, further polarizer and analyzer collectively consist of a total of three optical polarizers.

25. The control of claim 20, wherein the direction of the transmissive axis of said analyzer is orthogonal to the reference direction.

26. 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.

27. The eye protection gear of claim 26, said further polarizer means comprising a further polarizer operatively related at an angle other than parallel to the transmissive axes of said polarizer and said analyzer

28. The eye protection gear of claim 27, said further polarizer and said polarizer being operatively related and positioned relative to each other such that the respective transmissive axes thereof are at other than orthogonal relation.

29. The eye protection gear of claim 26, further comprising switching means optically in series with said polarizer and said analyzer for switching the effective optical relation of the transmissive axes of said polarizer and said analyzer selectively to change light transmission through said polarizer means.

30. The eye protection gear of claim 29, further comprising further switching means optically in series with said analyzer and said further polarizer means for switching the effective optical relation of the transmissive axes of said analyzer and said further polarizer means selectively to change light transmission through said further polarizer means.

31. The eye protection gear of claim 30, said switching means and further switching means each comprising a respective liquid crystal cell.

32. The eye protection gear of claim 31, each of said liquid crystal cells comprising a liquid crystal cell that affects light based on the principle of variable optical retardation.

33. A light control device, comprising

plural light polarizers, and

switching means positioned relative to said light polarizers for switching the relative operational orientation of the respective transmissive axes of at least two of said polarizers. and

said light polarizers consisting of only three plane polarizers and said switching means comprising a first liquid crystal cell optically between two of said polarizers and a second liquid crystal cell optically between two of said polarizers, wherein the polar directions of rub or other alignment of said respective liquid crystal cells are substantially equi-angularly spaced and on opposite sides of a reference direction, and wherein the polar directions of alignment of the transmissive axis of two of said polarizers are substantially equi-angularly spaced and on opposite sides of said reference direction.

34. The control of claim 33, further comprising means for adjusting the quadrature components of light transmitted relative to said first liquid crystal cell and further means for adjusting the quadrature components of light transmitted relative to said second liquid crystal cell.

35. The control of claim 34, wherein said means for adjusting and further means for adjusting have respective slow and fast axes, and wherein the polar alignment directions of the respective slow and fast axes of said means for adjusting relative to the respective slow and fast axes of said further means for adjusting are substantially equi-angularly spaced and on opposite sides of said reference direction.

36. The control of claim 33, wherein the direction of the transmissive axis of the third polarizer analyzer is orthogonal to the reference direction and said third polarizer is optically between said first and second polarizers.

37. 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.

38. A method of manufacturing a light transmission control device, comprising assembling a plurality of identical optical components, each having substantially identical alignment characteristics, positioning at least two of said optical components in back-to-back optical series, 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.

39. A light transmission control device, comprising

a plurality of identical optical components, each having substantially identical alignment characteristics, at least two of said optical components being positioned in back-to-back optical series, whereby the polar alignment of at least one part of both of said optical components is equi-angularly spaced relative to and on opposite sides of a reference direction.

40. 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.

41. 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.

42. The eye protection device of claim 41, further including a second analyzer in optical series with said second polarizer.

43. The eye protection device of claim 42, wherein said second polarizer and said second analyzer have transmissive axes oriented substantially operationally orthogonal to one another.

44. The eye protection device of claim 41, wherein the respective transmission axes of said second polarizer and said first analyzer are oriented substantially at 45 degrees to one another.

45. The eye protection device of claim 41, further including at least one wave plate positioned between said first analyzer and said second polarizer.

46. The eye protection device of claim 41, including a liquid crystal device positioned between said first polarizer and said first analyzer.

47. The eye protection device of claim 46, wherein said liquid crystal device is a tunable birefringence device.

48. The eye protection device of claim 47, wherein said tunable birefringence device is a surface mode liquid crystal device.