Light-emitting device and electronic device

• US 7,566,902 B2
• Filed: 05/06/2004
• Issued: 07/28/2009
• Est. Priority Date: 05/16/2003
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nemoto, Yukie, Seo, Satoshi, Nakashima, Harue
• Primary Examiner(s): Nguyen; Thinh T
• Application Number:
  US10/839,340
• Publication Number:
  US 20040227159A1
• Time in Patent Office: 1,909 Days
• Field of Search: 257/212, 257/40, 257/643, 257/E39.003, 257/59, 257/72, 257/83, 257/E33.064, 257/E27.131
• US Class Current: 257/59
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0847 being a dynamic memory without any storage capacitor, i.e. with use of parasitic capacitances as storage elements
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: H10K 59/128 comprising two independent displays, e.g. for emitting information from two major sides of the display

Abstract

The present invention provides a light-emitting device that can independently display images of both front and back sides, in a light emitting device that can display in the both sides and also provides a light-emitting device in which the aperture ratio of both or either of front and back displays increases. A light-emitting device has a structure in which a first light-emitting element and a second light-emitting element that are adjacent to each other are arranged in matrix; wherein the first light-emitting element can emit light to a first side of a substrate and the second light-emitting element can emit light to a second side that is opposite to the first side of the substrate. And light-emission of the first light-emitting element to the second side is shielded and light-emission of the second light-emitting element to the first side is shielded. In each light-emitting element, since a side opposite to a light-emitting side has a film having a light shielding effect, light-emission can be performed separately in each side.

Claims

1. A light-emitting device comprising:

a pixel portion in which a first light-emitting element and a second light-emitting element are adjacent to each other and formed over a substrate; and

a first semiconductor element connected to the first light-emitting element and a second semiconductor element connected to the second light-emitting element, the first and second semiconductor elements formed over the substrate,

wherein the first light-emitting element emits light in a direction of a first side of the substrate and the second light-emitting element emits light in a direction of a second side that is opposite to the first side of the substrate,

wherein light-emission of the first light-emitting element in the direction of the second side is shielded and light-emission of the second light-emitting element in the direction of the first side is shielded, and

wherein the first and second semiconductor elements are covered with one of the first light-emitting element and the second light-emitting element.

2. An electric device comprising the light-emitting device according to claim 1.

3. An electric device according to claim 2, wherein the electric device is selected from the group consisting of a video camera, a digital camera, a laptop personal computer, a personal digital assistant, a mobile computer, a portable telephone, a portable game machine, an electronic book, an image reproduction device having a recording, a TV image receiver, and an electric signboard.

4. A light-emitting device comprising:

a first light-emitting element and a second light-emitting element that are adjacent to each other formed over a substrate; and

a first semiconductor element connected to the first light-emitting element and a second semiconductor element connected to the second light-emitting element, the first and second semiconductor elements formed over the substrate,

wherein the first light-emitting element has a laminate structure in which a first light-transparent electrode, a light-emitting substance containing layer, and a second light-transparent electrode are sequentially formed from the substrate,

wherein the second light-emitting element has a laminate structure in which a third light-transparent electrode, the light-emitting substance containing layer, and the second light-transparent electrode are sequentially formed from the substrate,

wherein the first light-emitting element is formed over a first light shielding film and the first and second semiconductor elements, and

wherein the second light-emitting element is covered with a second light shielding film.

5. A device according to claim 4, wherein the first light-transparent electrode and the third light-transparent electrode comprise a same material.

6. An electric device comprising the light-emitting device according to claim 4.

7. An electric device according to claim 6, wherein the electric device is selected from the group consisting of a video camera, a digital camera, a laptop personal computer, a personal digital assistant, a mobile computer, a portable telephone, a portable game machine, an electronic book, an image reproduction device having a recording, a TV image receiver, and an electric signboard.

8. A light-emitting device comprising:

a pixel portion in which a first light-emitting element and a second light-emitting element are adjacent to each other and formed over a substrate; and

a first semiconductor element connected to the first light-emitting element and a second semiconductor element connected to the second light-emitting element, the first and second semiconductor elements formed over the substrate,

wherein the first light-emitting element emits light in a direction of a first side of the substrate and the second light-emitting element emits light in a direction of a second side that is opposite to the first side of the substrate,

wherein light-emission of the first light-emitting element in the direction of the second side is shielded and light-emission of the second light-emitting element in the direction of the first side is shielded,

wherein the first and second semiconductor elements are covered with one of the first light-emitting element and the second light-emitting element,

wherein the first light emitting element is formed over a first light shielding film, and

wherein the second light emitting element is covered with a second light shielding film.

9. An electric device comprising the light-emitting device according to claim 8.

10. An electric device according to claim 9, wherein the electric device is selected from the group consisting of a video camera, a digital camera, a laptop personal computer, a personal digital assistant, a mobile computer, a portable telephone, a portable game machine, an electronic book, an image reproduction device having a recording, a TV image receiver, and an electric signboard.

11. A light-emitting device comprising:

a pixel portion in which a first light-emitting element and a second light-emitting element are adjacent to each other and formed over a substrate; and

a first semiconductor element connected to the first light-emitting element and a second semiconductor element connected to the second light-emitting element, the first and second semiconductor elements formed over the substrate,

wherein the first light-emitting element emits light in a direction of a first side of the substrate and the second light-emitting element emits light in a direction of a second side that is opposite to the first side of the substrate,

wherein light-emission of the first light-emitting element in the direction of the second side is shielded and light-emission of the second light-emitting element in the direction of the first side is shielded,

wherein the first and second semiconductor elements are covered with one of the first light-emitting element and the second light-emitting element, and

wherein at least one of the first light-emitting element and the second light-emitting element has a light-transparent electrode.

12. An electric device comprising the light-emitting device according to claim 11.

13. An electric device according to claim 12, wherein the electric device is selected from the group consisting of a video camera, a digital camera, a laptop personal computer, a personal digital assistant, a mobile computer, a portable telephone, a portable game machine, an electronic book, an image reproduction device having a recording, a TV image receiver, and an electric signboard.