Self-emission display device and method for driving the same

• US 7,038,640 B2
• Filed: 03/19/2002
• Issued: 05/02/2006
• Est. Priority Date: 03/21/2001
• Status: Expired due to Fees

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Tanabe, Takahisa
• Primary Examiner(s): Shankar, Vijay
• Assistant Examiner(s): DHARIA, PRABODH M
• Application Number:
  US10/100,035
• Publication Number:
  US 20020135547A1
• Time in Patent Office: 1,505 Days
• Field of Search: 345/76, 345/80, 345/45, 345/36, 345/44, 345/82, 315/169.3, 348/223, 348/223.1, 257/113, 363/97
• US Class Current: 345/76
• 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 2300/088 using a non-linear two-terminal element
• CPC Class Codes: G09G 2310/06 Details of flat display driving waveforms
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3216 using a passive matrix
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3266 Details of drivers for scan electrodes
• CPC Class Codes: G09G 3/3275 Details of drivers for data electrodes
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

A self emission display device for controlling a lit-up/non-lit-up state of a light emitting element by controlling a current flowing therethrough comprises: a plurality of light emitting elements arrayed in a matrix; and a plurality of SCRs for controlling a current flowing through the light emitting elements, corresponding to each of the light emitting elements; wherein each of the light emitting elements is connected to an anode in each of the SCRs.

Claims

1. A self emission display device for controlling a lit-up/non-lit-up state of a light emitting element by controlling a current flowing therethrough comprising:

a plurality of light emitting elements arrayed in a matrix and connected to electrodes; and

a plurality of SCRs for controlling a current flowing through the light emitting elements, corresponding to each of the light emitting elements;

wherein each of the light emitting elements is connected to an anode in each of the SCRs,

wherein said each of the SCRs is provided so as to correspond to each of said light emitting elements connected to electrodes.

3. The self emission display device according to claim 1 or 2, wherein the light emitting elements are organic EL elements.

4. The self emission display device according to claim 1 or 2, wherein the light emitting elements are light emitting diodes.

5. The self emission display device according to claim 1 or 2, wherein a ratio in static capacity between the SCR and the light emitting element is adjusted to thereby optimize a ratio of a voltage applied to the SCR and a voltage applied to the light emitting element in a non-conducting state.

6. The self emission display device according to claim 1 or 2, wherein the self emission display device has a control function to set a current value that corresponds to a target brightness based on a current vs. brightness characteristic of the light emitting element to thereby set an optimal source voltage that corresponds to the set current value based on voltage vs. current characteristics of both the SCR and the light emitting element.

7. The self emission display device according to claim 1 or 2, wherein the lit-up/non-lit-up states of each of the light emitting elements are determined by a voltage value applied to a gate in each of the SCRs.

8. The self emission display device according to claim 1 or 2, wherein a break-over voltage in each of the SCRs is determined by a voltage value applied to a gate in each of the SCRs, the light emitting element is lighted up by decreasing the break-over voltage.

2. A self emission display device for controlling a lit-up/non-lit-up state of a light emitting element by controlling a current flowing therethrough comprising:

a plurality of light emitting elements arrayed in a matrix and connected to electrodes; and

a plurality of SCRs for controlling a current flowing through the light emitting elements, corresponding to each of the light emitting elements;

wherein each of the light emitting elements is connected to a cathode in each of the SCRs,

wherein said each of the SCRs is provided so as to correspond to each of said light emitting elements connected to electrodes.

9. A method for driving a self emission display device having a plurality of light emitting elements arrayed in a matrix and a plurality of SCRs for controlling a current flowing through the light emitting elements, wherein each of the light emitting elements is connected to an anode in each of the SCRs, comprising:

a process of providing a plurality of light emitting elements, each of said light emitting elements connected to an anode of a respective SCR and each of said light emitting elements connected to electrodes;

a process of scanning sequentially each of the SCRs; and

a process of driving each of the SCRs so that each of the light emitting elements be sustained in a conducting or non-conducting state,

wherein each said respective SCR is provided so as to correspond to each of said light emitting elements connected to electrodes.

10. A method for driving a self emission display device having a plurality of light emitting elements arrayed in a matrix and a plurality of SCRs for controlling a current flowing through the light emitting elements, wherein each of the light emitting elements is connected to a cathode in each of the SCRs, comprising:

a process of providing a plurality of light emitting elements, each of said light emitting elements connected to an anode of a respective SCR and each of said light emitting elements connected to electrodes;

a process of scanning sequentially each of the SCRs; and

a process of driving each of the SCRs so that each of the light emitting elements be sustained in a conducting or non-conducting states,

wherein each said respective SCR is provided so as to correspond to each of said light emitting elements connected to electrodes.

12. The method for driving a self emission display device according to claim 9 or 10, wherein the light emitting elements are organic EL elements.

13. The method for driving a self emission display device according to claim 9 or 10, wherein the light emitting elements are light emitting diodes.

14. The method for driving a self emission display device according to claim 9 or 10, wherein a ratio in static capacity between the SCR and the light emitting element is adjusted to thereby optimize a ratio of a voltage applied to the SCR and a voltage applied to the light emitting element in a non-conducting state.

15. The method for driving a self emission display device according to claim 9 or 10, wherein the method comprises:

a process of setting a current value that corresponds to a target brightness based on a current vs. brightness characteristic of the light emitting element; and

a process of setting an optimal source voltage that corresponds to the set current value based on voltage vs. current characteristics of both the SCR and the light emitting element.

16. The method for driving a self emission display device according to claim 9 or 10, wherein:

each of the SCRs are of a P-gate type, each of the gates of which are connected to a common gate switch that can switch over a high potential and a low potential for each column in a matrix, each of the anodes of which are connected via their respective ones of the light emitting elements to a common power source, and each of the cathodes of which are connected for each row thereof in the matrix to a common scan switch that can switch over a high potential, a low potential, and an intermediate potential;

when each of the light emitting elements is in a non-selected period, the gate switches is set to the high potential and the scan switches is set to the intermediate potential; and

when each of the light emitting elements is in a selected period, the scan switches is set to the high potential and then to the low potential and, to light up any one of the light emitting element, the gate switches is set to the high potential in a period when the scan switch is at the low potential and also, not to light up the light emitting element, the gate switches is set to the lower potential in a period when the scan switch is at the low potential, to thereby sustain a conducting/non-conducting state of each of the light emitting elements in driving.

17. The method for driving a self emission display device according to claim 9 or 10, wherein:

each of the SCRs are of an N-gate type, each of the gates of which are connected to a common gate switch that can switch over a high potential and a low potential for each column in a matrix, each of the cathodes of which are connected via their respective ones of the light emitting elements to a common power source, and each of the anodes of which are connected for each row thereof in the matrix to a common scan switch that can switch over a high potential, a low potential, and an intermediate potential;

when each of the light emitting elements is in non-selected period, the gate switches is set to the high potential and the scan switches is set to the intermediate potential; and

when each of the light emitting elements is in a selected period, the scan switches is set to the high potential and then to the low potential and, to light up any one of the light emitting element, the gate switches is set to the low potential in a period when the scan switch is at the high potential and also, not to light up the light emitting element, the gate switches is set to the high potential in a period when the scan switch is at the high potential, to thereby sustain a conducting/non-conducting state of each of the light emitting elements in driving.

11. A method for driving a self emission display device having a plurality of light emitting elements arrayed in a matrix and a plurality of SCRs for controlling a current flowing through the light emitting elements, comprising:

a process of providing a plurality of light emitting elements, each of said light emitting elements connected to an anode of a respective SCR and each of said light emitting elements connected to electrodes;

a process of scanning sequentially each of the SCRs to provide each of the light emitting elements with a selected period in which a lit-up/non-lit-up state of the light emitting elements is determined; and

a process of applying a predetermined voltage to a gate of the corresponding one of the SCRs in the selected period to light up any of the light emitting elements,

wherein each said respective SCR is provided so as to correspond to each of said light emitting elements connected to electrodes.