Apparatus and method for driving self-emitting display device

• US 6,265,833 B1
• Filed: 11/09/1999
• Issued: 07/24/2001
• Est. Priority Date: 11/20/1998
• Status: Expired due to Term

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Eun Young, Kim, Moo Seop, Kim, Sung Tae, Kim, Hak Su
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VO, TUYET THI
• Application Number:
  US09/436,730
• Time in Patent Office: 623 Days
• Field of Search: 315/169.3, 315/291-294, 315/299, 315/300, 315/301, 315/307, 315/308, 315/149-159, 315/224, 315/225, 362/800
• US Class Current: 315/169.3
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/22 using controlled light sources

Abstract

An apparatus and method for driving a self-emitting display device is provided, in which a driving voltage and a driving current are linearly controlled in accordance with variation of the outside environment to automatically control emitting luminance of the display device. The apparatus for driving a self-emitting display device provided with an optical signal converter and a display device includes: a controller for outputting a control signal for converting a predetermined driving current and driving voltage in accordance with a signal converted by the optical signal converter and a signal indicating whether or not the display device is in use; and a driver for simultaneously converting the driving current and driving voltage applied to the display device to a linear driving current and driving voltage in accordance with the control signal output from the controller, so that emitting luminance of the display device is automatically controlled and at the same time power consumption is optimally set. The method for driving a self-emitting display device includes the steps of sensing the intensity of light in the outside environment, converting the sensed intensity of light to an electrical signal, detecting a driving mode corresponding to the electrical signal, and controlling driving power of the self-emitting display device in accordance with the driving mode, so that power consumption is small and eyestrain of a user is removed.

Claims

1. An apparatus for driving a self-emitting display device the self-emitting display selected from organic electroluminescent displays, inorganic electroluminescent displays, field-emission displays, plasma displays, or light emitting diodes, the apparatus being provided with an optical signal converter for converting external light to an electrical signal and a display device, comprising:

a controller for providing a control signal for selecting a predetermined driving current and driving voltage in accordance with a signal converted by the optical signal converter and a signal indicating whether or not the display device is in use; and

a driver for simultaneously providing the driving current and driving voltage in accordance with the control signal output from the controller, and automatically controlling emitting luminance of the display device and at the same time optimally setting power consumption, wherein the driver comprises;

a driving current controller for controlling the driving current in accordance with the driving mode control signal of the controller;

a driving voltage controller for controlling an actual driving voltage in accordance with the driving mode control signal of the controller;

a driving voltage generator for generating the actual driving voltage corresponding to the control signal output from the driving voltage controller; and

a driving driver for driving a panel in accordance with both the driving current output from the driving current controller and the actual driving voltage generated by the driving voltage generator, and controlling the emitting luminance.

2. A method for driving a self-emitting display device the self-emitting display selected from organic electroluminescent displays, inorganic electroluminescent displays, field-emission displays, plasma displays, or light emitting diodes, in which the intensity of light of the outside environment is sensed to convert the sensed intensity of light to an electrical signal, comprising:

detecting whether or not a display device is in use;

outputting a control signal for selecting a predetermined driving current and driving voltage in accordance with the converted electrical signal representing the sensed light intensity;

controlling levels of the predetermined driving current and driving voltage in accordance with the control signal to set levels of an actual driving current and actual voltage;

outputting a second control signal for converting the predetermined driving current and driving voltage to a driving current of a minimum value and a driving voltage of a minimum value, if the display device is not in use as a result of the detecting step;

driving the display device by setting levels of an actual driving current of a minimum value and an actual driving voltage of a minimum value corresponding to the driving current and the driving voltage of the minimum value in accordance with the second control signal; and

automatically controlling emitting luminance of the display device in accordance with the level of the predetermined driving current and the level of the actual driving voltage.

3. An apparatus for driving a self-emitting display device provided with an optical signal converter for converting external light and a display device, comprising:

a controller for selecting driving modes corresponding to a predetermined driving current and driving voltage in accordance with a signal converted by the optical signal converter and a signal indicating whether or not the display device is in use, and outputting a corresponding driving mode control signal; and

a driver for simultaneously converting the driving current and driving voltage applied to the display device in accordance with the driving mode control signal output from the controller, and automatically controlling emitting luminance of the display device and at the same time optimally setting power consumption wherein the driver includes a driving current controller for controlling the current in accordance with the driving mode control signal of the controller, a driving voltage controller for controlling an actual driving voltage in accordance with the driving mode control signal of the controller, a driving voltage generator for generating the actual driving voltage corresponding to the control signal output to the driving voltage controller, and a driving driver for driving a panel in accordance with both the driving current output from the driving current controller and the actual driving voltage generated by the driving voltage generator.

4. An apparatus for driving a self-emitting display device provided with an optical signal converter for converting external light to an electrical signal and a display device, comprising:

a controller for selecting driving modes corresponding to a predetermined driving current and driving voltage in accordance with a signal provided by the optical signal converter and a signal indicating whether or not the display device is in use, and outputting a corresponding driving mode control signal; and

a driver for simultaneously providing the driving current and driving voltage applied to the display device in accordance with the driving mode control signal output from the controller, and automatically controlling emitting luminance of the display device and at the same time optimally setting power consumption wherein the driving modes are divided into a plurality of driving modes and wherein a first driving mode is used indoor or outdoor at night, a second driving mode in bright indoor or rainy outdoor, a third driving mode in cloudy and shaded outdoor, and a fourth driving mode in bright indoor environments.

5. A method for driving a self-emitting display device in which the intensity of light of the outside environment is sensed to convert the sensed intensity of light to an electrical signal, comprising the steps of:

detecting whether or not a display device is in use;

selecting a first driving mode by setting a driving current and an actual driving voltage at a minimum value if the display device is not in use, to control emitting luminance of the display device;

comparing the converted electrical signal with a predetermined first reference value if the display device is in use;

selecting a second driving mode if the converted electrical signal is less than the first reference value;

comparing the converted electrical signal with a second reference value if the converted electrical signal is greater than the first reference value;

selecting a third driving mode if the converted electrical signal is less than the second reference value;

selecting a fourth driving mode if the converted electrical signal is greater than the second reference value;

setting a level of the driving current and a level of an actual driving voltage of the driving voltage in accordance with the selected driving mode; and

automatically controlling the emitting luminance of the display device in accordance with the set driving current level and actual driving voltage level.

6. The method for driving a self-emitting display device as claimed in claim 5, wherein the first to fourth driving modes are set in accordance with a step wave form or a linear wave form varied by the outside environment.

7. An apparatus for driving a self-emitting display device the self-emitting display selected from organic electroluminescent displays, inorganic electroluminescent displays, field-emission displays, plasma displays, or light emitting diodes, the apparatus being provided with an optical signal converter for converting external light to an electrical signal and a display device, comprising:

a controller for selecting driving modes corresponding to a predetermined driving current and driving voltage in accordance with a signal provided by the optical signal converter and a signal indicating whether or not the display device is in use, and outputting a corresponding driving mode control signal; and

a driver for simultaneously providing the driving current and driving voltage applied to the display device in accordance with the driving mode control signal output from the controller, and automatically controlling emitting luminance of the display device and at the same time optimally setting power consumption, wherein the driver comprises;

a driving current controller for controlling the driving current in accordance with the driving mode control signal of the controller; and

a driving voltage controller for controlling an actual driving voltage in accordance with the driving mode control signal of the controller.

8. The apparatus for driving a self-emitting display device as claimed in claim 7, wherein the controller includes a driving mode selector for linearly selecting a driving mode corresponding to the predetermined driving current and driving voltage in accordance with the signal converted by the optical signal converter and the signal indicating whether or not the display device is in use.

9. The apparatus for driving a self-emitting display device as claimed in claim 7, wherein the driver further comprises:

a driving voltage generator for generating the actual driving voltage corresponding to the control signal output from the driving voltage controller; and

a driving driver for driving a panel in accordance with both the driving current output from the driving current controller and the actual driving voltage generated by the driving voltage generator, and controlling the emitting luminance.

10. The apparatus for driving a self-emitting display device as claimed in claim 7, wherein the self-emitting display device is any one of an organic field emitting display device, an inorganic field emitting display device, an inorganic emitting diode, and a field effect display device.

11. The apparatus for driving a self-emitting display device as claimed in claim 7, wherein the driving modes are set in accordance with a step wave form or a linear wave form varied by the outside environment.

12. The apparatus for driving a self-emitting display device as claimed in claim 7, wherein the driving modes are divided into first to fourth driving modes.

13. The apparatus for driving a self-emitting display device as claimed in claim 12, wherein the first driving mode is used in the indoor or the outdoor at night, the second driving mode in the bright indoor or the rainy outdoor, the third driving mode in the cloudy and shaded outdoor, and the fourth driving mode in the bright outdoor.

14. A method for driving a self-emitting display device in which the intensity of light of the outside environment is sensed and the sensed intensity of light is converted to an electrical signal, comprising:

detecting whether or not a display device is in use;

linearly selecting a driving mode of a driving current and driving voltage by comparing the converted electrical signal representing the sensed light intensity with predetermined reference values, and outputting a corresponding driving mode control signal;

setting a level of the driving current and a level of an actual driving voltage of the driving voltage in accordance with the driving mode control signal; and

automatically controlling emitting luminance of the display device in accordance with the set driving current level and actual driving voltage level wherein a plurality of driving modes are employed, a first driving mode being used indoor or outdoor at night, a second driving mode being used in bright indoor or rainy outdoor, a third driving mode being used in cloudy and shaded outdoor, and a fourth driving mode being used in bright indoor environments.

15. The method of driving a self-emitting display device as claimed in claim 14, wherein the step of outputting the driving mode control signal includes the steps of:

selecting a first driving mode by setting the driving current and the actual driving voltage at a minimum value if the display device is not in use as a result of the detecting step to control the emitting luminance of the display device;

comparing the converted electrical signal with the predetermined first reference value if the display device is in use; and

selecting second to fourth driving modes in accordance with the comparted result.

16. The method for driving a self-emitting display device as claimed in claim 14, wherein the step of selecting the second to fourth driving modes includes the steps of:

selecting the second driving mode if the converted electrical signal is less than the first reference value;

selecting the third driving mode if the converted electrical signal is less than the second reference value; and

selecting the fourth driving mode if the converted electrical signal is greater than the second reference value.

17. The method for driving a self-emitting display device as claimed in claim 14, wherein the first driving mode is used in the indoor or the outdoor at night, the second driving mode in the bright indoor or the rainy outdoor, the third driving mode in the cloudy and shaded outdoor, and the fourth driving mode in the bright outdoor.

18. The method for driving a self-emitting display device as claimed in claim 14, wherein the first to fourth driving modes are set in accordance with a step wave form or a linear wave form varied by the outside environment.