Luminescent display panel drive unit and drive method thereof

• US 6,351,076 B1
• Filed: 10/06/2000
• Issued: 02/26/2002
• Est. Priority Date: 10/06/1999
• Status: Expired due to Fees

• Current Assignee: Tohoku Pioneer Company Limited (Pioneer Corporation)
• Original Assignee: Tohoku Pioneer Company Limited (Pioneer Corporation)
• Inventors: Satake, Yoichi, Yoshida, Takayoshi
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): Vu, Jimmy T.
• Application Number:
  US09/679,516
• Time in Patent Office: 508 Days
• Field of Search: 315/169.1, 315/169.2, 315/169.3, 315/169.4, 345/214, 345/55, 345/77
• US Class Current: 315/169.1
• CPC Class Codes: G09G 2300/06 Passive matrix structure, i.e. with direct application of both column and row voltages to the light emitting or modulating elements, other than LCD or OLED
• CPC Class Codes: G09G 2310/0221 with use of split matrices G09G3/3644 and G09G3/3666 take precedence
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/063 Waveforms for resetting the whole screen at once
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/3216 using a passive matrix
• CPC Class Codes: G09G 3/3266 Details of drivers for scan electrodes
• CPC Class Codes: G09G 3/3283 in which the data driver supplies a variable data current for setting the current through, or the voltage across, the light-emitting elements

Abstract

There is specified an illumination drive line assigned to a capacitive luminescent element which is connected to a single scanning line and is to be illuminated in accordance with an input video signal during a scanning period. A first potential lower than an illumination threshold voltage of the capacitive luminescent element is applied to a single scanning line, and a second potential higher than the illumination threshold voltage is applied to the scanning lines other than the single scanning line. A drive current is supplied to the illumination drive line for forwardly applying a positive voltage higher than the illumination threshold voltage to the capacitive luminescent element to be illuminated. A third potential slightly lower than the illumination threshold voltage is applied to the drive lines other than the illumination drive line. During a reset period defined between scanning periods, the second potential is applied to all the scanning lines, and a fourth potential equal to the second potential is supplied to the drive line other than the non-reset drive line.

Claims

1. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and connected to the scanning lines and drive lines and which have polarities,

said drive unit comprising;

control means for setting a scanning period during which a single scanning line is selected from the plurality of scanning lines in accordance with a scan timing of an input video signal, for specifying a light-emission drive line assigned to said capacitive luminescent element which is connected to the single scanning line and is to be illuminated in accordance with the input video signal during the scanning period, and for setting a reset period during an interval between scanning periods;

scanning means for applying a first potential lower than an illumination threshold voltage of said capacitive luminescent element to the single scanning line during the scanning period, for applying a second potential higher than the illumination threshold voltage to scanning lines other than the single scanning line, and for applying the second potential to all the scanning lines during the reset period; and

drive means for supplying a drive current to the illumination drive line for forwardly applying, during the scanning period, a positive voltage higher than the illumination threshold voltage to said capacitive luminescent element to be illuminated, for applying a third potential slightly lower than the illumination threshold voltage to the drive lines other than the illumination drive line, and for supplying during the reset period a fourth potential equal to the second potential to all the drive lines.

2. The luminescent display panel drive unit as defined in claim 1, wherein

the first potential is ground potential, and

the second potential is substantially equal to a specified illumination voltage of said capacitive luminescent element.

3. The luminescent display panel drive unit as defined in claim 1, wherein

the drive current is supplied from a current source.

4. The luminescent display panel drive unit as defined in claim 1, wherein

said capacitive luminescent element is an organic electro-luminescent element.

5. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and connected to the scanning lines and drive lines and which have polarities,

said drive unit comprising;

control means for setting a scanning period during which a single scanning line is selected from the plurality of scanning lines in accordance with a scan timing of an input video signal, for specifying a light-emission drive line assigned to said capacitive luminescent element which is connected to the single scanning line and is to be illuminated in accordance with the input video signal during the scanning period, for setting a reset period during an interval between scanning periods, and for specifying, as a non-reset drive line, at least the drive line having connected to said capacitive luminescent element to remain unilluminated during the scanning periods before and after the reset period;

scanning means for applying a first potential lower than an illumination threshold voltage of said capacitive luminescent element to the single scanning line during the scanning period, for applying a second potential higher than the illumination threshold voltage to scanning lines other than the single scanning line, and for applying the second potential to all the scanning lines during the reset period; and

drive means for supplying a drive current to the illumination drive line for forwardly applying, during the scanning period, a positive voltage higher than the illumination threshold voltage to said capacitive luminescent element to be illuminated, for applying a third potential slightly lower than the illumination threshold voltage to the drive lines other than the illumination drive line, for supplying during the reset period a fourth potential equal to the second potential to the plurality of drive lines exclusive of the non-reset drive line, and for applying the third potential to the non-reset drive line.

6. The luminescent display panel drive unit as defined in claim 5, wherein

the first potential is ground potential, and the second potential is substantially equal to a specified illumination voltage of said capacitive luminescent element.

7. The luminescent display panel drive unit as defined in claim 5, wherein

the drive current is supplied from a current source.

8. The luminescent display panel drive unit as defined in claim 5, wherein

said capacitive luminescent element is an organic electro-luminescent element.

9. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and connected to the scanning lines and drive lines and which have polarities,

said drive unit comprising;

control means for setting a scanning period during which a single scanning line is selected from the plurality of scanning lines in accordance with a scan timing of an input video signal, for specifying a light-emission drive line assigned to said capacitive luminescent element which is connected to the single scanning line and is to be illuminated in accordance with the input video signal during the scanning period, for setting a reset period during an interval between scanning periods, and for specifying, as a non-reset drive line, only the drive line connected to only said capacitive luminescent element to remain unilluminated during the scanning period subsequent to the reset period;

scanning means for applying a first potential lower than an illumination threshold voltage of said capacitive luminescent element to the single scanning line during the scanning period, for applying a second potential higher than the illumination threshold voltage to scanning lines other than the single scanning line, and applying the second potential to all the scanning lines during the reset period; and

drive means for supplying a drive current to the illumination drive line for forwardly applying, during the scanning period, a positive voltage higher than the illumination threshold voltage to said capacitive luminescent element to be illuminated, for applying a third potential slightly lower than the illumination threshold voltage to the drive lines other than the illumination drive line, for supplying during the reset period a fourth potential equal to the second potential to the plurality of drive lines exclusive of the non-reset drive line, and for applying the third potential to the non-reset drive line.

10. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and connected to the scanning lines and drive lines and which have polarities,

said drive unit comprising;

control means for setting a scanning period during which a single scanning line is selected from the plurality of scanning lines in accordance with a scan timing of an input video signal, for specifying a light-emission drive line assigned to said capacitive luminescent element which is connected to the single scanning line and is to be illuminated in accordance with the input video signal during the scanning period, for setting a reset period during an interval between scanning periods, and for specifying, as a non-reset drive line, only the drive line having connected to said capacitive luminescent element to remain unilluminated during the scanning periods before and after the reset period;

scanning means for applying a first potential lower than an illumination threshold voltage of said capacitive luminescent element to the single scanning line during the scanning period, for applying a second potential higher than the illumination threshold voltage to scanning lines other than the single scanning line, and for applying the second potential to all the scanning lines during the reset period; and

drive means for supplying a drive current to the illumination drive line for forwardly applying, during the scanning period, a positive voltage higher than the illumination threshold voltage to said capacitive luminescent element to be illuminated, for applying a third potential slightly lower than the illumination threshold voltage to the drive lines other than the illumination drive line, for supplying during the reset period a fourth potential equal to the second potential to the plurality of drive lines exclusive of the non-reset drive line, and for applying the third potential to the non-reset drive line.

11. The luminescent display panel drive unit as defined in claim 10, wherein

the first potential is ground potential, and

the second potential is substantially equal to a specified illumination voltage of said capacitive luminescent element.

12. The luminescent display panel drive unit as defined in claim 10, wherein

the drive current is supplied from a current source.

13. The luminescent display panel drive unit as defined in claim 10, wherein

said (capacitive luminescent element is an organic electro-luminescent element.

14. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and connected to the scanning lines and drive lines and which have polarities, said drive unit comprising;

control means for setting a scanning period during which a single scanning line is selected from the plurality of scanning lines in accordance with a scan timing of an input video signal, for specifying a light-emission drive line assigned to said capacitive luminescent element which is connected to the single scanning line and is to be illuminated in accordance with the input video signal during the scanning period, for setting a reset period during an interval between scanning periods, and for specifying, as a non-reset drive line, only the drive line connected to only said capacitive luminescent element to remain unilluminated during the scanning period subsequent to the reset period;

scanning means for applying a first potential lower than an illumination threshold voltage of said capacitive luminescent element to the single scanning line during the scanning period, for applying a second potential higher than the illumination threshold voltage to scanning lines other than the single scanning line, and applying the second potential to all the scanning lines during the reset period; and

drive means for supplying a drive current to the illumination drive line for forwardly applying, during the scanning period, a positive voltage higher than the illumination threshold voltage to said capacitive luminescent element to be illuminated, for applying a third potential slightly lower than the illumination threshold voltage to the drive lines other than the illumination drive line, for supplying during the reset period a fourth potential equal to the second potential to the plurality of drive lines exclusive of the non-reset drive line, and for applying the third potential to the non-reset drive line.

15. A luminescent display panel drive unit including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and are connected to the scanning lines and drive lines and which have polarities,

said drive unit comprising;

determination means for distinguishing, as real scanning lines from the plurality of scanning lines, scanning lines which are connected to said capacitive luminescent elements to be illuminated during each scanning period;

control means which sequentially specifies one scanning line from the real scanning lines and specifies light-emission drive lines assigned to said capacitive luminescent elements to be illuminated every time one scanning line is specified, said luminescent elements being connected to the specified scanning line; and

drive means for forwardly supplying a drive current to said capacitive luminescent elements to be illuminated, by way of the scanning line and the light-emission drive line every time one scanning line is specified.

16. The luminescent display panel drive unit as defined in claim 15, wherein

said control means sets the duration of the scanning period so as to correspond to the number of real scanning lines.

17. The luminescent display panel drive unit as defined in claim 15, wherein

said control means has a variable current source for outputting, to said capacitive luminescent elements to be illuminated, a drive current of a level corresponding to the number of real scanning lines.

18. The luminescent display panel drive unit as defined in claim 15, wherein

said drive means has a variable voltage source for producing a voltage of a level corresponding to the number of real scanning lines, and a variable current source for outputting into said capacitive luminescent elements to be illuminated the drive current of a level corresponding to the number of real scanning lines.

19. The luminescent display panel drive unit as defined in claim 15, wherein

said drive means has a variable voltage source for applying to said capacitive luminescent elements to be illuminated a voltage of a level corresponding to the number of real scanning lines.

20. The luminescent display panel drive unit as defined in claim 15, wherein

said (control means sets a reset period between the scanning periods, and

said drive means brings all the drive lines and all the scanning lines into a single potential during the reset period.

21. The luminescent display panel drive unit as defined in claim 15, wherein

said capacitive luminescent element is an organic electro-luminescent element.

22. A method of driving a luminescent display panel including

a plurality of drive lines and a plurality of scanning lines, which intersect each other;

and

a plurality of capacitive luminescent elements which are provided in respective intersections between the drive lines and the scanning lines and are connected to the scanning lines and drive lines and which have polarities,

said method comprising the steps of;

distinguishing, as real scanning lines from the plurality of scanning lines, scanning lines which are connected to capacitive luminescent elements to be illuminated during each scanning period;

sequentially specifying one scanning line from the real scanning lines and specifies light-emission drive lines assigned to said capacitive luminescent elements to be illuminated every time one scanning line is specified, the luminescent elements being connected to the specified scanning line; and

forwardly supplying a drive current to said capacitive luminescent elements to be illuminated, by way of the scanning line and the light-emission drive line every time one scanning line is specified.