SEMI-TRANSPARENT/TRANSFLECTIVE LIGHTED INTERFEROMETRIC DEVICES

• US 20090073540A1
• Filed: 09/09/2008
• Published: 03/19/2009
• Est. Priority Date: 09/17/2007
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Khazeni, Kasra, Sethi, Gaurav, Kothari, Manish, Griffiths, Jonathan Charles
• Granted Patent: US 7,848,003 B2
• Time in Patent Office: Days
• US Class Current: 359/291
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 5/286 having four or fewer layers, e.g. for achieving a colour effect

Abstract

In certain embodiments, a device is provided that utilizes both interferometrically reflected light and transmitted light. Light incident on the device is interferometrically reflected from a plurality of layers of the device to emit light in a first direction, the interferometrically reflected light having a first color. Light from a light source is transmitted through the plurality of layers of the device to emit from the device in the first direction, the transmitted light having a second color.

Claims

1. A device comprising:

a substrate that is at least partially optically transparent;

a first layer over the substrate, wherein the first layer is partially optically absorptive, partially optically reflective, and partially optically transmissive;

a second layer over the substrate and spaced from the first layer, the first layer located between the substrate and the second layer, wherein the second layer is partially optically absorptive, partially optically reflective, and partially optically transmissive; and

a light source responsive to a signal and positioned relative to the substrate such that the first layer and the second layer are located between the substrate and the light source, wherein light emitted from the device in a first direction comprises;

a first portion of light incident on the substrate, transmitted through the substrate, transmitted through the first layer, reflected by the second layer, transmitted through the first layer, transmitted through the substrate, and emitted from the substrate in the first direction;

a second portion of light incident on the substrate, transmitted through the substrate, reflected by the first layer, transmitted through the substrate, and emitted from the substrate in the first direction; and

a third portion of light from the light source incident on the second layer, transmitted through the second layer, transmitted through the first layer, transmitted through the substrate, and emitted from the substrate in the first direction.

2. The device of claim 1, wherein the substrate comprises a glass or plastic material.

3. The device of claim 1, wherein the second layer comprises aluminum and has a thickness less than 300 Angstroms.

4. The device of claim 1, further comprising a dielectric layer located between the first layer and the second layer, the dielectric layer at least partially optically transparent.

5. The device of claim 1, wherein at least one of the first layer and the second layer is selectively movable so as to change a spacing between the first layer and the second layer.

6. The device of claim 1, wherein the first portion of light and the second portion of light interfere to produce light having a first color and the third portion of light has a second color different from the first color.

7. The device of claim 1, wherein the first portion of light and the second portion of light interfere to produce light having a first color and the light emitted from the device in the first direction has a second color different from the first color.

8. The device of claim 1, wherein the light emitted from the device in the first direction has a first color when the light source emits light and a second color when the light source does not emit light, the second color different from the first color.

9. The device of claim 1, wherein the light emitted by the device has a first color when the light source emits light and ambient light is incident on the device, a second color when the light source emits light and ambient light is not incident on the device, and a third color when the light source does not emit light and ambient light is incident on the device.

10. The device of claim 1, wherein the light source is responsive to the signal by changing from emitting light having a first selected color to emitting light having a second selected color different from the first selected color.

11. The device of claim 1, wherein the first portion of light and the second portion of light interfere to produce light having a first color and exhibiting a first angular color shift and the third portion of light has a second color and exhibits a second angular color shift different from the first angular color shift.

12. The device of claim 1, wherein the first portion of light and the second portion of light interfere to produce light having a first color and exhibiting a first angular color shift and the light emitted from the device in the first direction has a second color and exhibits a second angular color shift different from the first angular color shift.

13. The device of claim 1, wherein the light emitted from the device in the first direction has a first color and exhibits a first angular color shift when the light source emits light and a second color and second angular color shift when the light source does not emit light, the second angular color shift different from the first angular color shift.

14. The device of claim 1, wherein the light emitted by the device has a first color and exhibits a first angular color shift when the light source emits light and ambient light is incident on the device, a second color and a second angular color shift when the light source emits light and ambient light is not incident on the device, and a third color and a third angular color shift when the light source does not emit light and ambient light is incident on the device.

15. The device of claim 1, wherein light emitted from the device in a second direction generally opposite to the first direction comprises:

a fourth portion of light incident on the substrate, transmitted through the substrate, transmitted through the first layer, transmitted through the second layer, and emitted from the device in the second direction;

a fifth portion of light incident on the second layer, transmitted through the second layer, reflected from the first layer, transmitted through the second layer, and emitted from the device in the second direction; and

a sixth portion of light incident on the second layer, reflected from the second layer, and emitted from the device in the second direction.

16. The device of claim 15, wherein the fifth portion of light comprises light emitted by the light source and the sixth portion of light comprises light emitted by the light source.

17. The device of claim 15, wherein the light emitted from the device in the first direction has a first color, and the light emitted from the device in the second direction has a second color, the second color different from the first color.

18. The device of claim 15, wherein the light emitted from the device in the first direction and the light emitted from the device in the second direction have substantially the same color.

19. The device of claim 1, further comprising a third layer over the substrate and spaced from the first layer and from the second layer, wherein the third layer is partially optically absorptive, partially optically reflective, and partially optically transmissive.

20. The device of claim 19, wherein the third layer is located between the first layer and the second layer.

21. The device of claim 1, further comprising a first glass layer and a second glass layer, wherein the substrate, the first layer, and the second layer comprise a structure laminated and located between the first glass layer and the second glass layer and wherein at least one of the first glass layer and the second glass layer comprises textured glass.

22. The device of claim 1, wherein the second layer comprises has a thickness in the range of 30 to 300 Angstroms.

23. The device of claim 1, wherein the first layer has a thickness in the range of 50 to 60 Angstroms.

24. The device of claim 1, wherein the light source is responsive to the signal by changing from emitting light having a first selected brightness to emitting light having a second selected brightness different from the first selected brightness.

25. A device comprising:

a first means for partially absorbing light, partially reflecting light, and partially transmitting light;

a second means for partially absorbing light, partially reflecting light, and partially transmitting light, the second means spaced from the first means; and

a means for generating light, wherein light emitted from the device in a first direction comprises;

a first portion of light incident on the first means, transmitted through the first means, reflected by the second means, transmitted through the first means, and emitted from the device in the first direction;

a second portion of light incident on the first means, reflected by the first means, and emitted from the device in the first direction; and

a third portion of light generated by the light generation means, incident on the second means, transmitted through the second means, transmitted through the first means, and emitted from the device in the first direction.

26. The device of claim 25, wherein the light generation means comprises a light source responsive to a signal and positioned relative to the substrate such that the first layer and the second layer are located between the substrate and the light source.

27. A method of displaying an image, the method comprising:

providing a device comprising;

a substrate that is at least partially optically transparent;

a first layer over the substrate, wherein the first layer is partially optically absorptive, partially optically transmissive, and partially optically reflective; and

a second layer over the substrate and spaced from the first layer, the first layer located between the substrate and the second layer, wherein the second layer is partially optically absorptive, partially optically transmissive, and partially optically reflective;

positioning a light source responsive to a signal relative to the substrate such that the first layer and the second layer are located between the substrate and the light source;

emitting light from the device in a first direction, the emitted light comprising;

a first portion of light incident on the substrate, transmitted through the substrate, transmitted through the first layer, reflected by the second layer, transmitted through the first layer, transmitted through the substrate, and emitted from the device in the first direction;

a second portion of light incident on the substrate, transmitted through the substrate, reflected by the first layer, transmitted through the substrate, and emitted from the device in the first direction; and

a third portion of light from the light source incident on the second layer, transmitted through the second layer, transmitted through the first layer, transmitted through the substrate, and emitted from the device in the first direction.

28. The method of claim 27, further comprising selectively moving at least one of the first layer and the second layer so as to change a spacing between the first layer and the second layer.

29. The method of claim 27, further comprising modulating the signal so as to modulate one or more properties of the light emitted in the first direction.

30. The method of claim 27, further comprising emitting light from the device in a second direction generally opposite to the first direction comprising:

a fourth portion of light incident on the substrate, transmitted through the substrate, transmitted through the first layer, transmitted through the second layer, and emitted from the device in the second direction;

a fifth portion of light incident on the second layer, transmitted through the second layer, reflected from the first layer, transmitted through the second layer, and emitted from the device in the second direction; and

a sixth portion of light incident on the second layer, reflected from the second layer, and emitted from the device in the second direction.