CIRCUITS FOR CONTROLLING DISPLAY APPARATUS

• US 20140043223A1
• Filed: 08/09/2012
• Published: 02/13/2014
• Est. Priority Date: 08/09/2012
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Lewis, Stephen R., ENGLISH, Stephen
• Granted Patent: US 9,047,830 B2
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/3433 using light modulating elements actuated by an electric field and being other than liquid crystal devices and electrochromic devices using liquid crystal devices G09G3/36; using electrochromic devices G09G3/38
• CPC Class Codes: G09G 3/3473 based on light coupled out of a light guide, e.g. due to scattering, by contracting the light guide with external means
• CPC Class Codes: G09G 3/348 based on the deformation of a fluid drop, e.g. electrowetting

Abstract

An apparatus includes a plurality of display elements arranged in an array and a control matrix coupled to the plurality of display elements to communicate data and drive voltages to the display elements. For each display element, the control matrix includes an actuation circuit coupling a voltage source to the display element. The control matrix is configured to apply an actuation voltage to an actuator of the display element throughout an actuation stroke of the actuator and to initiate the actuation of the actuator after a pre-charging signal that initiated the application of the actuation voltage to the actuator has been deactivated.

Claims

1. An apparatus, comprising:

a plurality of display elements arranged in an array; and

a control matrix coupled to the plurality of display elements to communicate data and drive voltages to the display elements,

wherein the control matrix, for each display element, includes;

an actuation circuit coupling a voltage source to a respective display element and configured to apply an actuation voltage to an actuator of the respective display element throughout an actuation stroke of the actuator; and

wherein the control matrix is configured to initiate the actuation of the actuator after a pre-charging signal that initiated the application of the actuation voltage to the actuator has been deactivated.

2. The apparatus of claim 1, wherein the actuation circuit is coupled to a global update interconnect and the actuation circuit is configured to selectively remove the actuation voltage applied to the actuator in response to activation of the global update interconnect.

3. The apparatus of claim 2, wherein the actuation circuit includes a source follower circuit.

4. The apparatus of claim 2, wherein the actuation circuit includes an actuation discharge transistor coupled to the global update interconnect, and the actuation voltage is removed by being discharged through the actuation discharge transistor.

5. The apparatus of claim 4, wherein the actuation discharge transistor is selectively activated based on a data voltage stored at the data store.

6. The apparatus of claim 1, wherein the actuation circuit is coupled to a pre-charge node and controlled by the pre-charging signal on the pre-charge node, the pre-charge node coupled to a pre-charge voltage source that provides the pre-charging signal.

7. The apparatus of claim 6, wherein the pre-charge voltage on the pre-charge node for the display element is controlled by the pre-charge signal voltage source and a pre-charge discharge switch that maintains the voltage on the pre-charge node provided by the pre-charge signal voltage source until the pre-charge discharge switch is activated.

8. The apparatus of claim 1, wherein the control matrix, for each display element, includes a second actuation circuit coupling the voltage source to the respective display element and configured to apply the actuation voltage to a second actuator of the respective display element throughout a second actuation stroke of the actuator in a direction different from the first actuation stroke;

and wherein the control matrix is configured to initiate the actuation of the second actuator after a second pre-charging signal that initiated the application of the actuation voltage to the second actuator has been deactivated.

9. The apparatus of claim 8, wherein the second actuation circuit is coupled to a second global update interconnect, wherein the control matrix is configured to actuate one of the actuator and the second actuator by activating one of the global update interconnect and the second global update interconnect prior to activating the other of the global update interconnect and the second global update interconnect.

10. The apparatus of claim 9, wherein the second actuation circuit configured to selectively remove the actuation voltage applied to the second actuator in response to activation of the second global update interconnect.

11. The apparatus of claim 10, wherein the actuation circuit includes an actuation discharge transistor coupled to the second global update interconnect, and the actuation voltage is removed by being discharged through the actuation discharge transistor.

12. The apparatus of claim 11, wherein the second actuation discharge transistor is selectively activated based on an output of the actuation discharge transistor.

13. The apparatus of claim 1, wherein the control matrix includes only n-type transistors.

14. The apparatus of claim 1, wherein the control matrix includes only p-type transistors.

15. The apparatus of claim 1, wherein the apparatus includes a display apparatus and the display elements include light modulators.

16. The apparatus of claim 1, wherein the display elements include electromechanical system (EMS) display elements.

17. The apparatus of claim 1, wherein the display elements include microelectromechanical system (MEMS) display elements.

18. The apparatus of claim 1, further comprising:

a display including the array of display elements;

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

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

19. The apparatus of claim 18, further comprising:

a driver circuit configured to send at least one signal to the display; and

wherein

the controller further configured to send at least a portion of the image data to the driver circuit.

20. The apparatus of claim 19, further comprising:

an image source module configured to send the image data to the processor, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

21. The apparatus of claim 20, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

22. The apparatus of claim 18, wherein the display elements include light modulators.

23. An apparatus, comprising:

a plurality of display elements arranged in an array; and

a control matrix coupled to the plurality of display elements to communicate data and drive voltages to the display elements,

wherein the control matrix, for each display element, includes;

a first actuation circuit coupling a voltage source to a respective display element and configured to apply an actuation voltage to a first actuator of the respective display element throughout an actuation stroke of the first actuator;

a second actuation circuit coupling the voltage source to the display element and configured to apply the actuation voltage to a second actuator of the display element throughout an actuation stroke of the second actuator; and

wherein the control matrix is configured to initiate the actuation of one of the first actuator and the second actuator after a pre-charging signal that initiated the application of the actuation voltage to the first actuator and the second actuator has been deactivated.

24. The apparatus of claim 23, wherein the first actuation circuit is coupled to a first global update interconnect and the first actuation circuit is configured to selectively remove the actuation voltage applied to the first actuator in response to deactivation of the first global update interconnect;

and wherein the second actuation circuit is coupled to a second global update interconnect and the second actuation circuit is configured to selectively remove the actuation voltage applied to the first actuator in response to deactivation of the second global update interconnect.

25. The apparatus of claim 24, wherein the control matrix is configured to actuate one of the first actuator and the second actuator in response to the deactivation of one of the first global update interconnect and the second global update interconnect prior to the deactivation of the other of the first global update interconnect and the second global update interconnect.

26. The apparatus of claim 25, wherein the control matrix is configured to actuate one of the first actuator and the second actuator based on a data voltage stored at a data store capacitor.

27. The apparatus of claim 23, wherein the first actuator circuit and the second actuator circuit are governed by the pre-charging signal on a pre-charge node, the pre-charge node coupled to a pre-charge voltage source that activates the pre-charging signal.

28. The apparatus of claim 23, wherein the control matrix includes only n-type transistors.

29. The apparatus of claim 23, wherein the control matrix includes only p-type transistors.

30. The apparatus of claim 23, wherein the apparatus includes a display apparatus and the display elements include light modulators.

31. The apparatus of claim 23, wherein the display elements include electromechanical system (EMS) display elements.

32. The apparatus of claim 23, wherein the display elements include microelectromechanical system (MEMS) display elements.