Self illuminating touch activated optical switch

• US 5,424,533 A
• Filed: 06/21/1994
• Issued: 06/13/1995
• Est. Priority Date: 06/21/1994
• Status: Expired due to Term

• Current Assignee: AOA Xinetics (Northrop Grumman Corporation)
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Schmutz, Lawrence E.
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): CALOGERO, STEPH
• Application Number:
  US08/263,224
• Time in Patent Office: 357 Days
• Field of Search: 250/221, 250/229, 341/31
• US Class Current: 250/221
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3582 Housing means or package or arranging details of the switching elements, e.g. for thermal isolation
• CPC Class Codes: H03K 17/9627 Optical touch switches
• CPC Class Codes: H03K 17/9631 using a light source as part of the switch

Abstract

The present invention teaches a touch activated switch. The switch comprises a light source for generating a light ray. Further, the switch comprises a first lens for collimating the light source'"'"'s light ray. The first lens, as a result, generates a collimated light ray in a first direction. In a second direction, the first lens forms a first and a second focal point, such that the light source is positioned at the first focal point. Moreover, the switch comprises a second lens for converging the collimated light ray to a surface. This surface scatters the collimated light ray in the direction of the first lens when the surface is substantially touched. The switch also comprises a detector for detecting the collimated light ray which have been scattered by touching the surface, with the detector being positioned at the second focal point, such that the switch is activated in response to touching the surface.

Claims

1. A self illuminating switch activated by touching a surface comprising:

a light source for generating a light ray;

a first lens for collimating said light ray to provide a collimated light ray in a first direction and for forming a first and a second focal point in a second direction, said light source being positioned at said first focal point;

a second lens for converging said collimated light ray to a surface, said surface scattering said collimated light ray to provide a scattered light ray at said first lens when said surface is substantially touched; and

a detector for detecting said scattered light ray, said detector being positioned at said second focal point, such that the switch is activated in response to touching said surface.

2. The switch of claim 1, wherein at least one of said first and second lenses comprises at least one of a micro-optic multiplet lenslet and a first and a second monolithic lenslet module.

3. The switch of claim 1, wherein at least one of said first and second lenses are formed on a substrate.

4. The switch of claim 1:

wherein said detector comprises a filtering means for reducing false triggers associated with the touching said surface and for reducing the effects of ambient light.

5. The switch of claim 4, wherein said filtering means comprises a notch filter for selectively enabling a spectral band of energy emitted from said light source to be transmitted into said detector.

6. The switch of claim 1, wherein said detector comprises a light emitting diode detector.

7. The switch of claim 1, wherein said light source comprises a light emitting diode.

8. The switch of claim 1, wherein said at least one of said first and second lenses comprises a Holographic Optical Element ("HOE").

9. A switch activated by the position of an object comprising:

a first light source for generating a first light ray;

second light source for generating a second light ray;

a first lenslet comprising;

a first lens group for collimating said first light ray to provide a first collimated light ray in a first direction, and for forming a first and a second focal point in a second direction, each lens of said first lens group having a first diameter, said first light source being positioned at said first focal point; and

a second lens group for collimating said second light ray to provide a second collimated light ray in said first direction, and for forming a third and a fourth focal point in said second direction, each lens of said second lens group having a second diameter, said second light source being positioned at said second focal point;

a second lenslet comprising;

a third lens group for converging said first collimated light ray to a first sense point, wherein said first collimated light ray is substantially scattered to provide a first scattered recollimated light ray when the object is positioned at said first sense point; and

a fourth lens group for converging said second collimated light ray to a second sense point, wherein said second collimated light ray is substantially scattered to provide a second scattered recollimated light ray when the object is positioned at said second sense point;

a first detector for detecting said first scattered recollimated light ray, said first detector being positioned at said third focal point; and

a second detector for detecting said second scattered recollimated light ray, said second detector being positioned at said fourth focal point, such that the switch is activated in response to detecting at least one of said first and second scattered recollimated light rays.

10. The switch of claim 9, wherein at least one of said first and said second lenslets comprises an integrated monolithic lenslet module.

11. The switch of claim 9, wherein at least one of said first and second lenslets is formed on a substrate.

12. The switch of claim 9, further comprising:

means for preventing crosstalk between said collimated first light ray and said collimated second light ray, and between said scattered recollimated first light ray and said second scattered recollimated light ray.

13. The switch of claim 12, wherein said means for preventing crosstalk comprises an opaque inter-segment baffle.

14. The switch of claim 9, wherein said detector comprises a filtering means for reducing false triggers associated with positioning the object and for reducing the effects of ambient light.

15. The switch of claim 14, wherein said filtering means comprises a notch filter for selectively enabling a spectral band of energy emitted from said light source to be transmitted into said detector.

16. The switch of claim 9, wherein said at least one of said first and second detectors comprises a light emitting diode detector and at least one of said first and second light sources comprises a light emitting diode.

17. The switch of claim 9, wherein said at least one of said first and second lenslets comprises a Holographic Optical Element ("HOE").

18. A switch activated by the position of an object comprising:

a plurality of light sources for generating a plurality of light rays;

a first lenslet comprising a plurality of primary lenses, each lens of said plurality of primary lenses collimating a light ray of said plurality of light rays such that a plurality of collimated light rays are provided in a first direction, each lens of said primary lenses forming a plurality of pairs of focal points for each lens of said plurality of primary lenses in a second direction, each light source of said plurality of light sources being positioned at a first focal point of said plurality of pairs of focal points, each lens of said plurality of primary lenses having a diameter;

a second lenslet comprising a plurality of secondary lenses, each lens of said plurality of secondary lenses converging one collimated light ray of said plurality of collimated light rays to a sense point such that a plurality of sense points are created, wherein a scattered light ray is formed for each lens of said plurality of secondary lenses when the object is positioned at one sense point associated with said each lens of said plurality of secondary lenses, each lens of said plurality of secondary lenses having a diameter; and

a plurality of detectors for detecting scattered light rays, each of said plurality of detectors being positioned at one of said plurality of second focal points, such that the switch is activated in response to detecting said scattered light ray.

19. The switch of claim 18, wherein at least one of said first and said second lenslets comprises an integrated monolithic lenslet module.

20. The switch of claim 18, wherein at least one of said first and second lenslets is formed on a substrate.

21. The switch of claim 18, further comprising:

means for preventing crosstalk between said collimated first light ray and said collimated second light ray, and between said scattered first light ray and said second scattered light ray, said means for preventing crosstalk comprises an opaque intersegment baffle.

22. The switch of claim 18, wherein said detector comprises a filtering means for reducing false triggers associated with positioning the object and for reducing the effects of ambient light, said filtering means comprises a notch filter for selectively enabling a spectral band of energy emitted from said light source to be transmitted into said detector.

23. The switch of claim 18, wherein at least one of said first and second lenslets comprises a Holographic Optical Element ("HOE").