Emitter, method of designing brightness of emitter, program for method of designing brightness of emitter, electrooptical device and electric device

• US 20030141808A1
• Filed: 12/04/2002
• Published: 07/31/2003
• Est. Priority Date: 12/20/2001
• Status: Active Grant

• Current Assignee: Intellectual Keystone Technology LLC (Samsung Electronics Co. Ltd.)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kobayashi, Hidekazu
• Granted Patent: US 6,900,597 B2
• Time in Patent Office: Days
• US Class Current: 313/498
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels

Abstract

The invention provides an emitter comprising a plurality of types of emission units (for example, EL elements) with different emission aging characteristics, which can obtain good emission conditions even after a certain usage time has elapsed, and furthermore a method of designing the brightness and a program for designing the brightness of the emitter, an electrooptical device and an electric device.

An emitter comprises a plurality of types of emission units with different emission aging characteristics, and initial brightnesses of the emission units are set such that a skew of emission lifetime between the emission units is within 20%.

Claims

1. An emitter comprising a plurality of types of emission units with different emission aging characteristics, wherein

initial brightnesses of said emission units are set such that a skew of emission lifetime between said emission units is within 20%.

2. An emitter according to claim 1, wherein the emission lifetime of said emission units is defined as the time required until the emission brightness reaches a prescribed percentage of the initial brightness.

3. An emitter according to claim 2, wherein said prescribed percentage is 50%.

4. An emitter according to claim 1, wherein it is possible to display colors by constructing one picture element of three dots, being an emission unit capable of developing a red color, an emission unit capable of developing a green color and an emission unit capable of developing a blue color, and numerical apertures of said emission units satisfy the following equation;

a_r;

a_g;

a_b=W_rL_gL_b;

W_gL_rL_b;

W_bL_rL_g

where L_r is the initial brightness of the emission unit capable of developing a red color, L_g is the initial brightness of the emission unit capable of developing a green color, L_b is the initial brightness of the emission unit capable of developing a blue color, a_r is the numerical aperture of the emission unit capable of developing a red color, a_g is the numerical aperture of the emission unit capable of developing a green color, a_b is the numerical aperture of the emission unit capable of developing a blue color, and W_r;

W_g;

W_b is the brightness ratio of the colors (W_r corresponding to a red color, W_g a green color, and W_b a blue color) required for said one picture element to display white.

7. An emitter according to claim 1, wherein it is possible to display colors by constructing one picture element of three dots, being an emission unit capable of developing a red color, an emission unit capable of developing a green color, and an emission unit capable of developing a blue color, and a ratio of numerical apertures of said emission units satisfies the following equation;

a_r;

a_g;

a_b=1;

3 to 8;

8 to 15

where a_r is the numerical aperture of the emission unit capable of developing a red color, a_g is the numerical aperture of the emission unit capable of developing a green color, and a_b is the numerical aperture of the emission unit capable of developing a blue color.

25. An electrooptical device provided with an emitter according to any one of claim 1 through claim 8 as a display device.

26. An electric device provided with an emitter according to any one of claim 1 through claim 8 as a display device.

5. An emitter comprising a plurality of types of emission units with different emission aging characteristics, wherein

initial brightnesses and numerical apertures of said emission units are set such that a skew of emission intensity between said emission units is within 20% over a prescribed time.

6. An emitter according to claim 5, wherein the skew of the emission intensity between said emission units over a prescribed time is determined based on a normalized decay curve obtained by dividing a decay curve of the emission brightness of each of said emission units by the initial brightness of the emission brightness.

8. An emitter according to claim 5, wherein it is possible to display colors by constructing one picture element of three dots, being an emission unit capable of developing a red color, an emission unit capable of developing a green color, and an emission unit capable of developing a blue color, and a ratio of numerical apertures of said emission units satisfies the following equation;

a_r;

a_g;

a_b=1;

3 to 8;

8 to 15

where a_r is the numerical aperture of the emission unit capable of developing a red color, a_g is the numerical aperture of the emission unit capable of developing a green color, and a_b is the numerical aperture of the emission unit capable of developing a blue color.

9. A method of designing the brightness of an emitter comprising a plurality of types of emission units with different emission aging characteristics, wherein an initial value determination process is performed to set initial brightnesses of said emission units such that a skew of emission life between said emission units is within 20%.

10. A method of designing the brightness of an emitter according to claim 9, wherein a numerical aperture determination process for determining a numerical aperture for each type of said emission units is performed based on said determined initial values.

11. A method of designing the brightness of an emitter according to claim 9, wherein, a usage range determination process for determining a range of current values or voltage values used for each type of said emission unit is performed based on said initial values.

12. A method of designing the brightness of an emitter according to claim 9, wherein the emission lifetime of said emission units is defined as the time required until the emission brightness reaches a prescribed percentage of the initial brightness.

13. A method of designing the brightness of an emitter according to claim 12, wherein said prescribed percentage is 50%.

14. A method of designing the brightness of an emitter according to claim 9, wherein it is possible to display colors by constructing one picture element of three dots, being an emission unit capable of developing a red color, an emission unit capable of developing a green color, and an emission unit capable of developing a blue color, and numerical apertures of said emission units satisfy the following equation;

a_r;

a_g;

a_b=W_rL_gL_b;

W_gL_rL_b;

W_bL_rL_g

where L_r is the initial brightness of the emission unit capable of developing a red color, L_g is the initial brightness of the emission unit capable of developing a green color, L_b is the initial brightness of the emission unit capable of developing a blue color, a_r is the numerical aperture of the emission unit capable of developing a red color, a_g is the numerical aperture of the emission unit capable of developing a green color, a_b is the numerical aperture of the emission unit capable of developing a blue color, and W_r;

W_g;

W_b is the brightness ratio(W_r corresponding to a red color, W_g a green color, and W_b a blue color) of the colors required for said one picture element to display white.

15. A method of designing the brightness of an emitter comprising a plurality of types of emission units with different emission aging characteristics, which performs an initial value determination process and a numerical aperture determination process for setting initial brightnesses and numerical apertures of said emission units such that a skew of emission intensity between said emission units is within 20% over a prescribed time.

16. A method of designing the brightness of an emitter according to claim 15, wherein the skew of the emission intensity between said emission units over a prescribed time is determined based on a normalized decay curve obtained by dividing a decay curve of the emission brightness of each of said emission units by the initial brightness of the emission brightness.

17. A program for designing the brightness of an emitter comprising a plurality of types of emission units with different emission aging characteristics, wherein an initial value determination process is performed by computer to set initial brightnesses of said emission units such that a skew of emission lifetime between said emission units is within 20%.

18. A program for designing the brightness of an emitter according to claim 17, wherein a numerical aperture determination process is performed by computer to determine a numerical aperture for each type of said emission units based on said determined initial values.

19. A program for designing the brightness of an emitter according to claim 17, wherein a usage range determination process is performed by computer to determine a range of current values or voltage values used for each type of emission unit based on said determined initial values.

20. A method of designing the brightness of an emitter according to claim 17, wherein the emission life of said emission units is defined as the time required until the emission brightness reaches a prescribed percentage of the initial brightness.

21. A method of designing the brightness of an emitter according to claim 20, wherein said prescribed percentage is 50%.

22. A program for designing the brightness of an emitter according to claim 17, wherein it is possible to display colors by constructing one picture element of three dots, being an emission unit capable of developing a red color, an emission unit capable of developing a green color and an emission unit capable of developing a blue color, and numerical apertures of said emission units satisfy the following equation;

a_r;

a_g;

a_b=W_rL_gL_b;

W_gL_rL_b;

W_bL_rL_g

where L_r is the initial brightness of the emission unit capable of developing a red color, L_g is the initial brightness of the emission unit capable of developing a green color, L_b is the initial brightness of the emission unit capable of developing a blue color, a_r is the numerical aperture of the emission unit capable of developing a red color, a_g is the numerical aperture of the emission unit capable of developing a green color, a_b is the numerical aperture of the emission unit capable of developing a blue color, and W_r;

W_g;

W_b is the brightness ratio(W_r corresponding to a red color, W_g a green color, and W_b a blue color) of the colors required for said one picture element to display white.

23. A program for designing the brightness of an emitter comprising a plurality of types of emission units with different emission aging characteristics, wherein an initial value determination process and a numerical aperture determination process are performed by computer to set initial brightnesses and numerical apertures of said emission units such that a skew of emission intensity between said emission units is within 20% over a prescribed time.

24. A method of designing the brightness of an emitter according to claim 23, wherein the skew of the emission intensity between said emission units over a prescribed time is determined based on a normalized decay curve obtained by dividing a decay curve of the emission brightness of each of said emission units by the initial brightness of the emission brightness.