Deinterleaving transpose circuits in digital display systems

• US 7,315,294 B2
• Filed: 08/25/2003
• Issued: 01/01/2008
• Est. Priority Date: 08/25/2003
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Richards, Peter W.
• Primary Examiner(s): CHANG, KENT WU
• Application Number:
  US10/648,689
• Publication Number:
  US 20050057479A1
• Time in Patent Office: 1,590 Days
• Field of Search: 345/32, 345/84, 345/108, 345/691, 359/245, 359/242, 359/290, 359/291, 359/295, 359/298
• US Class Current: 345/84
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833

Abstract

The present invention provides a method and apparatus of converting a stream of pixel data in space and time into a stream of bitplane data. In particular, the present invention converts the pixel data stream according to a predetermined output format. The apparatus of the present invention receives the pixel data in a “real-time” fashion, and dynamically performs predefined permutations so as to accomplish the predefined transpose operation. Alternatively, the pixel data are stored in a storage medium, and the apparatus of the present invention retrieves the pixel data and performs the predefined permutation to accomplish the predefined transpose operation. The methods and apparatus disclosed herein are especially useful for processing a high-speed stream of digital data in a flow-through manner and suitable for implementation in a hardware video pipeline. The control signal fanout and gate count of this invention are reduced compared to currently available similar techniques for converting pixel data into bitplane data.

Claims

1. A method used in a spatial light modulator that comprises an array of pixels, for producing an image, the method comprising:

dividing the pixels of each row of the array into a plurality of subgroups such that at least two pixels in said each row are in different sub-groups;

receiving a set of pixel data streams, wherein the pixel data of each stream represent a set of states of a pixel of the spatial light modulator during different time intervals;

transforming the received pixel data streams into a set of bitplane data streams, wherein the bitplane data of each stream represent the states of a plurality of pixels during one time interval, such that the bitplane data streams representing the pixels of the same subgroup are parallel and adjacent; and

updating the states of the pixels using the transformed bitplane data.

2. The method of claim 1, wherein the bitplane data representing adjacent pixels of the spatial light modulator are parallel but not adjacent.

3. The method of claim 1, wherein the bitplane data streams representing the odd numbered pixels of the spatial light modulator are parallel and adjacent.

4. The method of claim 1, wherein the bitplane data streams representing the even numbered pixels of the spatial light modulator are parallel and adjacent.

5. The method of claim 1, wherein the state is selected from an ON state and an OFF state, and in the ON state, the pixel of the spatial light modulator represents a “

bright”

pixel of the image, and in the OFF state, the pixel represents a “

dark”

pixel of the image.

6. The method of claim 5, wherein the value of the pixel data determines the time duration of the pixel in the state.

7. The method of claim 1, wherein the time intervals are determined according to a pulse-width-modulation technique.

8. The method of claim 7, wherein the time intervals are determined according to a binary-weighted pulse-width-modulation technique.

9. The method of claim 1, further comprising:

storing the transformed bitplane data streams in a frame buffer having a plurality of storage regions such that the bitplane data streams representing the pixels of the same subgroup are stored consecutively in the same region of the frame buffer.

10. The method of claim 9, further comprising:

storing the transformed bitplane data streams in a frame buffer having a plurality of storage regions such that the bitplane data streams representing the pixels of separate subgroups are stored in different regions of the frame buffer.

11. The method of claim 9, further comprising:

upon receiving a writing signal,

retrieving the bitplane data of the first significance from a first region of the frame buffer; and

writing the pixels of the spatial light modulator with the retrieved bitplane data.

12. The method of claim 11, wherein the step of writing the pixels further comprises:

activating the pixels using a first wordline.

13. The method of claim 12, further comprising:

retrieving the bitplane data of the second significance from a second region of the frame buffer; and

writing the pixels of the spatial light modulator with the retrieved bitplane data.

14. The method of claim 13, wherein the step of writing the pixels further comprises:

activating the pixels using a second wordline.

15. The method of claim 13, wherein the pixel comprises a charge pump memory cell that further comprises:

a transistor having a source, a gate, and a drain;

a storage capacitor having a first plate and a second plate; and

wherein the source of said transistor is connected to a bitline, the gate of said transistor is connected to a wordline, and wherein the drain of the transistor is connected to the first plate of said storage capacitor forming a storage node, and wherein the second plate of said storage capacitor is connected to a pump signal.

16. A method used in a spatial light modulator that comprises an array of pixels, for producing an image, the method comprising:

dividing the pixels of each row of the array into a plurality of subgroups such that at least two pixels in said each row are in different sub-groups;

receiving a set of pixel data streams, wherein the pixel data of each stream represent a set of states of a pixel of the spatial light modulator during different time intervals;

transforming the received pixel data streams into a set of bitplane data streams according to a predetermined format, wherein the bitplane data of each stream represent the states of a plurality of pixels during one time interval, such that the bitplane data streams representing the pixels of different subgroups are interleaved; and

updating the states of the pixels using the transformed bitplane data.

17. The method of claim 16, wherein the state is selected from an ON state and an OFF state, and in the ON state, the pixel of the spatial light modulator represents a “

bright”

pixel of the image, and in the OFF state, the pixel represents a “

dark”

pixel of the image.

18. The method of claim 17, wherein the value of the pixel data determines the time duration of the pixel in the state.

19. The method of claim 16, wherein the time intervals are determined according to a pulse-width-modulation technique.

20. The method of claim 19, wherein the time intervals are determined according to a binary-weighted pulse-width-modulation technique.

21. The method of claim 16, further comprising:

storing the transformed bitplane data streams in a frame buffer having a plurality of storage regions such that the bitplane data streams representing the pixels of the same subgroup are stored consecutively in the same region of the frame buffer.

22. The method of claim 17, further comprising:

storing the transformed bitplane data streams in a frame buffer having a plurality of storage regions such that the bitplane data streams representing the pixels of separate subgroups are stored in different regions of the frame buffer.

23. The method of claim 21, further comprising:

upon receiving a writing signal,

retrieving the bitplane data of the first significance from a first region of the frame buffer; and

writing the pixels of the spatial light modulator with the retrieved bitplane data.

24. The method of claim 23, wherein the step of writing the pixels farther comprises:

activating the pixels using a first wordline.

25. The method of claim 24, further comprising:

retrieving the bitplane data of the second significance from a second region of the frame buffer; and

writing the pixels of the spatial light modulator with the retrieved bitplane data.

26. The method of claim 24, wherein the step of writing the pixels further comprises:

activating the pixels using a second wordline.