Current-driven emissive display device, method for driving the same, and method for manufacturing the same

• US 6,529,178 B1
• Filed: 10/13/1998
• Issued: 03/04/2003
• Est. Priority Date: 02/17/1997
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kimura, Mutsumi
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Eisen, Alexander
• Application Number:
  US09/171,117
• Time in Patent Office: 1,603 Days
• Field of Search: 345/76-83, 345/36, 345/45, 345/204, 345/208, 345/209, 345/211, 345/214, 340/825.81, 315/169.3
• US Class Current: 345/76
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0254 Control of polarity reversal in general, other than for liquid crystal displays
• CPC Class Codes: G09G 2310/0256 with the purpose of reversing the voltage across a light emitting or modulating element within a pixel
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 71/841 Applying alternating current [AC] during manufacturing or treatment

Abstract

A reduction in deterioration of a switching element over time in a current driving type emissive apparatus is realized. At the same time, a reduction in power consumption is realized. To this end, an AC voltage or an alternating current is applied between a source and a drain terminal of a switching element, and a DC voltage or a direct current is applied between a first and a second terminal of a luminescent element. This is realized by application of a voltage, which is inverted at predetermined intervals, to two luminescent elements heterogeneously arranged, to a luminescent element and a rectifier arranged in reverse orientation and in parallel, or to a full-wave rectification circuit. At this time, the rectifier is formed by a thin-film transistor, a PN junction, or a PIN junction, and is formed simultaneously with an existing switching element.

Claims

1. A display apparatus, comprising:

a plurality of scanning lines;

a plurality of data lines;

a plurality of first feeders; and

a plurality of second feeders,

a plurality of pixels, one pixel of the plurality of pixels further comprising;

a luminescent element; and

a transistor, one of a source and drain of the transistor being electrically connected to one of the plurality of first feeders, and the other one of the source and drain of the transistor being electrically connected to pixel electrodes,

the luminescence element being disposed between the transistor and one of the plurality of second feeders, an AC voltage being applied to the plurality of first and second feeders causing a direct current to flow through the luminescent element.

2. A display apparatus according to claim 1, further comprising:

at least one circuit for applying an AC voltage to the source or drain of said transistor to cause a direct current to flow through said luminescent element.

3. The display apparatus according to claim 1, further comprising:

the luminescent element comprising a first luminescent element component that emits a light by a current flowing from one of said pixel electrodes to said second feeder and a second luminescent element component that emits a light by a current flowing from said second feeder to another one of said pixel electrodes, the first luminescent element component and the second luminescent element component being electrically arranged in parallel.

4. The display apparatus according to claim 3, further comprising a method for driving said display apparatus, wherein a voltage between said first feeder and said second feeder is inverted at predetermined intervals.

5. The display apparatus according to claim 1, further comprising:

the one pixel further comprising a rectifier electrically arranged in parallel with the luminescent element.

6. The display apparatus according to claim 5, further comprising a method for driving the display apparatus, wherein a voltage between said first feeder and said second feeder is inverted at predetermined intervals.

7. The display apparatus according to claim 5, further comprising:

said luminescent element emitting a light by a current through the luminescent element flowing from one of the pixel electrodes to said one of the second feeders when the rectifier is formed such that a current flowing through the rectifier flows from the one of said second feeders to another one of the pixel electrodes, and

the luminescent element emitting a light by a current flowing through the luminescent element flowing from the one of the second feeders to the one of the pixel electrodes when the rectifier is formed such that a current flowing through the rectifier flows from another one of the pixel electrodes to the one of the second feeders.

8. The display apparatus according to claim 7, further comprising a method for driving the current driving type emissive display apparatus, wherein a voltage between said first feeder and said second feeder is inverted at predetermined intervals.

9. A display apparatus, comprising:

a plurality of scanning lines;

a plurality of data lines;

a plurality of first feeders; and

a plurality of second feeders,

a plurality of pixels, one pixel of the plurality of pixels further comprising;

a luminescent element; and

a transistor, one of a source and drain of the transistor being electrically connected to one of the plurality of first feeders, and the other one of the source and drain being electrically connected to pixel electrodes,

an AC voltage being applied to the plurality of first and second feeders that causes an alternating current to flow through the transistor, and a direct current to flow through the luminescent element.

10. A display apparatus according to claim 9, further comprising:

at least one circuit for controlling an alternating current flowing through said transistor, and for controlling a direct current flowing through said luminescent element.

11. The display apparatus according to claim 9, further comprising:

the luminescent element comprising a first luminescent element component that emits a light by a current flowing from one of said pixel electrodes to said second feeder and a second luminescent element component that emits a light by a current flowing from said second feeder to another one of said pixel electrodes, the first luminescent element component and the second luminescent element component being electrically arranged in parallel.

12. The display apparatus according to claim 9, further comprising:

the one pixel further comprising a rectifier electrically arranged in parallel with the luminescent element.

13. A display apparatus, comprising:

a plurality of scanning lines;

a plurality of data lines, said scanning lines and said data lines intersecting at a plurality of intersections;

a first feeder; and

a second feeder,

said display apparatus further having, in correspondence with each intersection of said scanning lines and said data lines;

a first switching element;

a second switching element;

a storage capacitor;

a pixel electrode and

a current driven luminescent element,

said first switching element controlling conduction between said data lines and said storage capacitor using a potential of said scanning lines, and said second switching element controlling conduction between said first feeder and said pixel electrode using a potential of said storage capacitor, to thereby emit light by a current flowing through said current driven luminescent element, which is arranged between a first electrode connected to said pixel electrode and a second electrode connected to said second feeder,

said display apparatus further comprising;

a first rectifier that causes a current to flow from said pixel electrode to said first electrode;

a second rectifier that causes a current to flow from said second electrode to said pixel electrode;

a third rectifier that causes a current to flow from said second feeder to said first electrode; and

a fourth rectifier that causes a current to flow from said second electrode to said second feeder,

wherein an AC voltage is applied to the first and second feeders to cause said current driven luminescent element to emit light by a direct current flowing from said first electrode through said current driven luminescent element to said second electrode.

14. The display apparatus according to claim 13, at least one of said first rectifier, said second rectifier, said third rectifier, and said fourth rectifier comprising a switching element for rectification, having a gate terminal connected to a source, or a drain terminal, and said switching element for rectification being formed simultaneously with at least one of said first switching element and said second switching element.

15. The display apparatus according to claim 13, at least one of said first rectifier, said second rectifier, said third rectifier, and said fourth rectifier being formed by a PN junction or a PIN junction, and formed simultaneously with at least one of said first switching element and said second switching element.