DISPLAY DEVICE AND DRIVING METHOD FOR DISPLAY DEVICE

• US 20120092587A1
• Filed: 10/04/2011
• Published: 04/19/2012
• Est. Priority Date: 10/14/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: WAKIMOTO, Kenichi
• Granted Patent: US 8,913,212 B2
• Time in Patent Office: Days
• US Class Current: 349/61
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

An object is to suppress degradation of an image quality of a display image. A plurality of display circuits arranged in M rows (M is a natural number of 2 or more) and N columns (N is a natural number) and a light unit are included; the light unit includes a plurality of light-emitting diode groups arranged in X rows (X is a natural number of 2 or more), overlaps with a display circuit in at least different one or more rows every row, and includes a light-emitting diode emitting red light, a light-emitting diode emitting green light and a light-emitting diode emitting blue light and a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups. The light guide plate includes X light guide members which transmits the light of the light-emitting diode groups in the rows different from each other.

Claims

1. A display device comprising:

a plurality of display circuits arranged in M rows (M is a natural number of 2 or more) and N columns (N is a natural number); and

a light unit, the light unit comprising;

a plurality of light-emitting diode groups arranged in X rows (X is a natural number of 2 or more), wherein the plurality of light-emitting diode groups arranged in one of the X rows overlaps with the plurality of display circuits arranged in one of M rows, the plurality of light-emitting diode groups arranged in another one of the X rows overlaps with the plurality of display circuits arranged in another one of the M rows, and includes a light-emitting diode emitting red light, a light-emitting diode emitting green light, and a light-emitting diode emitting blue light; and

a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups, the light guide plate comprising X light guide members which transmit light of the light-emitting diode groups in the rows different from each other.

2. The display device according to claim 1,

wherein the plurality of light-emitting diode groups is arranged in grid pattern.

3. The display device according to claim 1,

wherein the plurality of light-emitting diode groups is arranged in a staggered pattern.

4. The display device according to claim 1,

wherein each of the plurality of display circuits includes a display selection transistor and a liquid crystal element.

5. A display device comprising:

a plurality of display circuits arranged in M rows (M is a natural number of 2 or more) and N columns (N is a natural number); and

a light unit, the light unit comprising;

a plurality of light-emitting diode groups arranged in X rows (X is a natural number of 2 or more), wherein the plurality of light-emitting diode groups arranged in one of the X rows overlaps with the plurality of display circuits arranged in one of M rows, the plurality of light-emitting diode groups arranged in another one of the X rows overlaps with the plurality of display circuits arranged in another one of the M rows, and includes a light-emitting diode emitting red light, a light-emitting diode emitting green light, and a light-emitting diode emitting blue light;

a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups, the light guide plate comprising X light guide members; and

a diffusion sheet overlapping with the plurality of light-emitting diode groups with the light guide plate interposed therebetween,

wherein each of the X light guide members is a rectangular solid with a rectangular cross section,

wherein side surfaces of the X light guide members have light-reflective properties, and

wherein top and bottom surfaces of the X light guide members have light-transmitting properties, overlap with light-emitting diode groups in the rows different from each other out of the plurality of light-emitting diode groups.

6. The display device according to claim 5,

wherein the plurality of light-emitting diode groups is arranged in grid pattern.

7. The display device according to claim 5,

wherein the plurality of light-emitting diode groups is arranged in a staggered pattern.

8. The display device according to claim 5,

wherein each of the plurality of display circuits includes a display selection transistor and a liquid crystal element.

9. A display device comprising:

a plurality of display circuits arranged in M rows (M is a natural number of 2 or more) and N columns (N is a natural number); and

a light unit, the light unit comprising;

a plurality of light-emitting diode groups arranged in X rows (X is a natural number of 2 or more), wherein the plurality of light-emitting diode groups arranged in one of the X rows overlaps with the plurality of display circuits arranged in one of M rows, the plurality of light-emitting diode groups arranged in another one of the X rows overlaps with the plurality of display circuits arranged in another one of the M rows, and includes a light-emitting diode emitting red light, a light-emitting diode emitting green light, and a light-emitting diode emitting blue light;

a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups, the light guide plate comprising X light guide members overlapping with light-emitting diodes in successive plural rows out of the plurality of light-emitting diode groups; and

a diffusion sheet overlapping with the plurality of light-emitting diode groups with the light guide plate interposed therebetween,

wherein each of the X light guide members is a rectangular solid with a parallelogram cross section,

wherein side surfaces of the X light guide members have light-reflective properties,

wherein top and bottom surfaces of the X light guide members have light-transmitting properties, and

wherein bottom surfaces of the X light guide members overlap with light-emitting diode groups in the rows different from each other out of the plurality of light-emitting diode groups.

10. The display device according to claim 9,

wherein the plurality of light-emitting diode groups is arranged in grid pattern.

11. The display device according to claim 9,

wherein the plurality of light-emitting diode groups is arranged in a staggered pattern.

12. The display device according to claim 9,

wherein each of the plurality of display circuits includes a display selection transistor and a liquid crystal element.

13. A method for driving a display device including a plurality of display circuits arranged in M rows (M is a natural number of 2 or more) and N columns (N is a natural number) and a light unit, in which the light unit includes a plurality of light-emitting diode groups arranged in X rows (X is a natural number of 2 or more) including a light-emitting diode emitting red light, a light-emitting diode emitting green light and a light-emitting diode emitting blue light;

and a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups and including X light guide members configured to transmit light of light-emitting diode groups in the rows different from each other, the method comprising the steps of;

inputting a display selection signal to display circuits in each of the rows in accordance with a pulse of the display selection signal, and placing display circuit in a display state in accordance with data of the display selection signal in an input operation, wherein a pulse of the display selection signal different depending on the rows is sequentially input to the plurality of display circuits in different rows in each of a plurality of display regions including display circuit in at least one row and light-emitting diode groups provided in at least one row in the input operation; and

emitting light by at least one of the light-emitting diode emitting red light, the light-emitting diode emitting green light and the light-emitting diode emitting blue light, wherein a light-emitting diode in each of the plurality of display regions emits light every time a pulse of the display selection signal is input to display circuits in at least one row in a light-emitting operation;

wherein the input operation and the light-emitting operation are repeated Z times (Z is a natural number of 3 or more), and

wherein in K-th light-emitting operation (K is a natural number of 2 or more and Z or less), a light-emitting diode emitting light of colors different from a display data signal (K−

1)-th light-emitting operation emits light in each of the plurality of display regions.

14. A display device comprising:

a plurality of display circuits wherein a first part of the plurality of display circuits are arranged in a first row, and a second part of the plurality of display circuits are arranged in a second row; and

a light unit comprising;

a plurality of light-emitting diode groups wherein a first part of the plurality of light-emitting diode groups are arranged in a third row, and a second part of the plurality of light-emitting diode groups are arranged in a fourth row,

wherein the first part of the plurality of light-emitting diode groups overlap with the first part of the plurality of display circuits, and the second part of the plurality of light-emitting diode groups overlap with the second part of the plurality of display circuits, and

wherein each of the plurality of light-emitting diode groups includes a light-emitting diode emitting red light, a light-emitting diode emitting green light, and a light-emitting diode emitting blue light; and

a light guide plate formed between the plurality of display circuits and the plurality of light-emitting diode groups, and comprising a first light guide member and a second light guide member,

wherein the first light guide member transmits light of the first part of the plurality of light-emitting diode groups, and the second light guide member transmits light of the second part of the plurality of light-emitting diode groups.

15. The display device according to claim 14,

wherein the plurality of light-emitting diode groups is arranged in grid pattern.

16. The display device according to claim 14,

wherein the plurality of light-emitting diode groups is arranged in a staggered pattern.

17. The display device according to claim 14,

wherein each of the plurality of display circuits includes a display selection transistor and a liquid crystal element.