Plasma display panels and plasma display devices which use the panel

• US 20050236987A1
• Filed: 02/23/2005
• Published: 10/27/2005
• Est. Priority Date: 04/27/2004
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Kenichi, Okazaki, Choichiro, Shiiki, Masatoshi, Suzuki, Keizo
• Granted Patent: US 7,605,540 B2
• Time in Patent Office: Days
• US Class Current: 313/582
• CPC Class Codes: H01J 11/12 with main electrodes provided on both sides of the discharge space
• CPC Class Codes: H01J 11/44 Optical arrangements or shielding arrangements, e.g. filters, black matrices, light reflecting means or electromagnetic shielding means
• CPC Class Codes: H01J 2211/442 Light reflecting means; Anti-reflection means
• CPC Class Codes: H01J 2211/444 Means for improving contrast or colour purity, e.g. black matrix or light shielding means

Abstract

A plasma display panel has plurality discharge cells disposed between a pair of opposing first and second substrates. Each of the discharge cells includes at least: at least one pair of electrodes for generating a discharge for display; a discharge gas; and a phosphor film for emitting visible light by being excited by ultraviolet light produced by the discharge of the discharge gas. Laminated members are dispersed in a plane within each of the discharge cells inside the first substrate from which visible light for display is emitted. Each of the laminated members includes a light absorption layer disposed on a side of the first substrate on which ambient light is incident and a light reflection layer disposed on a phosphor-film side of each of the laminated members.

Claims

1. A plasma display panel comprising a plurality of discharge cells disposed between a pair of opposing first and second substrates,

each of said plurality of discharge cells comprising at least:

at least one pair of electrodes for generating a discharge for display;

a discharge gas; and

a phosphor film for emitting visible light by being excited by ultraviolet light produced by said discharge of said discharge gas,

wherein laminated members are dispersed in a plane within each of said plurality of discharge cells inside said first substrate from which visible light for display is emitted, and

each of said laminated members comprises a light absorption layer disposed on a side of said first substrate on which ambient light is incident and a light reflection layer disposed on a phosphor-film side of said each of said laminated members.

2. A plasma display panel according to claim 1, wherein said laminated members are integrally fabricated to form a unitary structure in said plane within each of said plurality of discharge cells and said unitary structure perforated with plural openings passing light therethrough in said plane.

3. A plasma display panel according to claim 1, wherein said laminated members are plural in number within each of said discharge cells, and are disposed separately from each other in said plane.

4. A plasma display panel according to claim 1, wherein said laminated members are plural in number within each of said discharge cells, and are disposed separately two-dimensionally from each other in said plane.

5. A plasma display panel according to claim 1, wherein an aperture ratio (S1 —

S2)/S1 satisfies the following inequality;

0.1≦

(S1−

S2)/S1≦

0.8,

where S1 is an area of an opening of one of said discharge cells for emitting said visible light therethrough projected onto said first substrate, and S2 is a sum of areas occupied by said light absorption layers within said area S1.

6. A plasma display panel according to claim 2, wherein said laminated members are fabricated in a pattern of one of a mesh and a ladder.

7. A plasma display panel according to claim 2, wherein said laminated members are provided with openings in a pattern of branches of a tree.

8. A plasma display panel according to claim 3, wherein said laminated members are formed in a pattern of one of (i) isolated islands and (ii) branches of a tree.

9. A plasma display panel according to claim 1, wherein said plasma display panel has at least one cross-section which satisfies the following inequality:

0<

La/L≦

0.5,

where, consider a cross section containing a line contained in a plane of said first substrate and perpendicular to said plane of said first substrate,

L is a length of one of said discharge cells as measured in a direction of said line, and

La is a minimum value of a length of said laminated members as measured in said direction of said line.

10. A plasma display device including at least a plasma display panel and a driving circuit which applies voltages to said plasma display panel,

wherein said plasma display panel comprises a front substrate through which visible light for display is emitted and a plurality of discharge cells;

each of said plurality of discharge cells is provided at least with electrodes for applying voltages to said each of said discharge cells, a discharge gas for generating discharge, a substance which generates visible light based upon said discharge, and laminated members each comprised at least of a light absorption layer and a light reflection layer; and

said front substrate defines a part of a discharge space which generates said discharge and forms part of a hermetic sealing,

wherein a visual field space is defined as a space on a side of said front substrate opposite from said discharge space,

a display surface is defined as a surface obtained by expanding over an entire area of each of said plurality of discharge cells a surface of said front substrate in contact with said discharge space,

a portion of said visible light emitted into said visual field space through said display surface serves as said visible light for display,

wherein a BM height hd is defined as an average of distances between a bottom surface of said discharge space and discharge-space-side surfaces of said laminated members, as measured perpendicularly to said display surface, where a first plane containing said laminated members is considered, and said bottom surface of said discharge space is a plane which faces said first plane across said discharge space and which bounds said discharge space,

wherein said laminated members are disposed one of (i) within said discharge space, (ii) between said discharge space and said front substrate, and (iii) within said front substrate, are each comprised of a light absorption layer disposed on a visual-field-space side thereof and a light reflection layer disposed on a discharge-space side thereof, and

wherein the following inequality is satisfied;

Lave/hd<

5,

where a BM region is defined as a region occupied by said laminated members in said display surface,

a light-transmissive region is defined as a region in said display surface through which said visible light from said discharge space is emitted into said visual field space,

a length dbm-A is defined as a shortest distance between an arbitrary point A in said BM region and said light-transmissive region, and

Lave is a value of said length dbm-A averaged over an entire area of said BM region with respect to said arbitrary point A.

11. A plasma display device according to claim 10, wherein said laminated members are fabricated in a pattern of one of (i) isolated islands, (ii) a mesh, (iii) a ladder, and (iv) branches of a tree.

12. A plasma display device according to claim 10, wherein said laminated members are comprised of electrical insulators.

13. A plasma display device according to claim 10, wherein said laminated members are comprised of electrical conductors.

14. A plasma display device according to claim 10, wherein said laminated members are comprised of a combination of an electrical insulator and an electrical conductor.

15. A plasma display device according to claim 10, wherein said laminated members are electrically insulated from said electrodes for applying voltages to said discharge cells.

16. A plasma display device according to claim 10, wherein a portion of each of said laminated members is electrically connected to a portion of said electrodes for applying voltages to said discharge cells and forms part or an entirety of said electrodes.

17. A plasma display device according to claim 13, wherein said electrodes for applying voltages to said discharge cells form at least part of display electrodes for producing discharge for a display, form at least two kinds of electrodes, X electrodes and Y electrodes, and portions of each of said laminated members form part or an entirety of said X and Y electrodes.

18. A plasma display device according to claim 10, wherein the following inequality is satisfied:

Lave/hd<

1.

19. A plasma display device according to claim 10, wherein said substance which generates visible light is a phosphor film which generates visible light excited by ultraviolet light produced by said discharge, and said BM height hd is an average of distances between a surface of said phosphor film and a phosphor-film-side surface of said laminated members.

20. A plasma display device according to claim 10, wherein said laminated members are disposed on or within said front substrate.