Interferometric modulator display devices

• US 7,847,999 B2
• Filed: 01/09/2008
• Issued: 12/07/2010
• Est. Priority Date: 09/14/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Lee, Donovan, Khazeni, Kasra
• Primary Examiner(s): Mack; Ricky L
• Assistant Examiner(s): Tra; Tuyen Q
• Application Number:
  US11/971,830
• Publication Number:
  US 20090073534A1
• Time in Patent Office: 1,063 Days
• Field of Search: 359/291, 359/290, 359/292, 359/245, 359/247, 359/250, 359/254, 359/259, 359/337.2, 359/902, 359/302, 359/298, 359/316, 359/305, 359/308
• US Class Current: 359/247
• 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: H04N 13/365 using digital micromirror devices [DMD]

Abstract

An embodiment for a pixel for a display device on a substrate is disclosed. The pixel includes a first interferometric modulator on the substrate. The first interferometric modulator has a first normal direction substantially perpendicular to the first interferometric modulator and a first angularly-dependent reflectivity function comprising a first reflectivity in a first direction and a second reflectivity in a second direction, with the first reflectivity being greater than the second reflectivity. The pixel also includes a second interferometric modulator on the substrate. The second interferometric modulator has a second normal direction substantially perpendicular to the second interferometric modulator and a second angularly-dependent reflectivity function comprising a third reflectivity in the second direction and a fourth reflectivity in the first direction, with the third reflectivity being greater than the fourth reflectivity.

Claims

1. A pixel for a display device on a substrate, the pixel comprising:

a first interferometric modulator on the substrate, the first interferometric modulator having a first normal direction substantially perpendicular to the first interferometric modulator and a first angularly-dependent reflectivity function comprising a first reflectivity in a first direction and a second reflectivity in a second direction, the first reflectivity greater than the second reflectivity, wherein a first angle between the first direction and the first normal direction is greater than a second angle between the second direction and the first normal direction; and

a second interferometric modulator on the substrate, the second interferometric modulator having a second normal direction substantially perpendicular to the second interferometric modulator and a second angularly-dependent reflectivity function comprising a third reflectivity in the second direction and a fourth reflectivity in the first direction, the third reflectivity greater than the fourth reflectivity, wherein a third angle between the second direction and the second normal direction is greater than a fourth angle between the first direction and the second normal direction,

wherein the first interferometric modulator is tilted with respect to a general plane of the substrate by a first tilt angle and the second interferometric modulator is tilted with respect to the general plane of the substrate by a second tilt angle, the first tilt angle approximately one half of the sum of the first angle and the second angle, and the second tilt angle approximately one half of the sum of the third angle and the fourth angle.

2. The pixel of claim 1, wherein the first angle or the third angle is in a range from about 20 degrees to about 40 degrees.

3. The pixel of claim 1, wherein the difference between the first angle and the second angle or the difference between the third angle and the fourth angle is in a range from about 5 degrees to about 30 degrees.

4. The pixel of claim 1, wherein the substrate is substantially transmissive to light in a selected wavelength range.

5. The pixel of claim 4, wherein the selected wavelength range comprises red light, green light, or blue light.

6. The pixel of claim 4, wherein the wavelength range has a bandwidth in a range from about 20 nm to about 100 nm.

7. The pixel of claim 1, further comprising a filter positioned such that light transmitted through the filter is incident on or reflected from the first interferometric modulator, the filter substantially transmissive to light in a selected wavelength range.

8. The pixel of claim 7, wherein the filter is on or adjacent to the substrate.

9. The pixel of claim 7, wherein the selected wavelength range includes red light, green light, or blue light.

10. The pixel of claim 7, wherein the selected wavelength range has a bandwidth in a range from about 20 nm to about 100 nm.

11. The pixel of claim 1, wherein the display device is positionable such that the first direction is directed to a first eye of a user and the second direction is directed to a second eye of the user.

12. The pixel of claim 1, further comprising:

the display device;

a processor that is configured to communicate with the display device, the processor being configured to process image data; and

a memory device that is configured to communicate with the processor.

13. The pixel of claim 12, further comprising a driver circuit configured to send at least one signal to the display device.

14. The pixel of claim 13, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

15. The pixel of claim 12, further comprising an image source module configured to send the image data to the processor.

16. The pixel of claim 15, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

17. The pixel of claim 1, further comprising an input device configured to receive input data and to communicate the input data to the processor.

18. A display device comprising a plurality of pixels on a substrate, each pixel comprising:

a first interferometric modulator on the substrate, the first interferometric modulator having a first normal direction substantially perpendicular to the first interferometric modulator and a first angularly-dependent reflectivity function comprising a first reflectivity in a first direction and a second reflectivity in a second direction, the first reflectivity greater than the second reflectivity, wherein a first angle between the first direction and the first normal direction is greater than a second angle between the second direction and the first normal direction; and

a second interferometric modulator on the substrate, the second interferometric modulator having a second normal direction substantially perpendicular to the second interferometric modulator and a second angularly-dependent reflectivity function comprising a third reflectivity in the second direction and a fourth reflectivity in the first direction, the third reflectivity greater than the fourth reflectivity, wherein a third angle between the second direction and the second normal direction is greater than a fourth angle between the first direction and the second normal direction,

wherein the first interferometric modulator is tilted with respect to a general plane of the substrate by a first tilt angle and the second interferometric modulator is tilted with respect to the general plane of the substrate by a second tilt angle, the first tilt angle approximately one half of the sum of the first angle and the second angle, and the second tilt angle approximately one half of the sum of the third angle and the fourth angle.

19. The display device of claim 18, wherein the device is configured to display a first image in the first direction and a second image in the second direction.

20. The display device of claim 19, wherein the display device is positionable such that the first direction is directed to a first eye of a user and the second direction is directed to a second eye of the user.

21. The display device of claim 20, wherein the first image and the second image are displayed substantially simultaneously to the user to produce an image appearing three-dimensional to the user.

22. A pixel for a display device, the pixel comprising:

a first means for interferometrically modulating light, the first modulating means formed on a substrate, the first modulating means having a first normal direction substantially perpendicular to the first modulating means and a first angularly-dependent reflectivity function comprising a first reflectivity in a first direction and a second reflectivity in a second direction, the first reflectivity greater than the second reflectivity, wherein a first angle between the first direction and the first normal direction eater a second angle between the second direction and the first normal direction; and

a second means for interferometrically modulating light, the second modulating means formed on the substrate, the second modulating means having a second normal direction substantially perpendicular to the second modulating means and a second angularly-dependent reflectivity function comprising a third reflectivity in the second direction and a fourth reflectivity in the first direction, the third reflectivity greater than the fourth reflectivity, wherein a third angle between the second direction and the second normal direction is greater than a fourth angle between the first direction and the second normal direction,

wherein the first modulating means is tilted with respect to a general plane of the substrate by a first tilt angle and the second modulating means is tilted with respect to the general plane of the substrate by a second tilt angle, the first tilt angle approximately one half of the sum of the first angle and the second angle, and the second tilt angle approximately one half of the sum of the third angle and the fourth angle.

23. The pixel of claim 22, wherein the first modulating means or the second modulating means comprises an interferometric modulator.