Light-emitting apparatus having periodic structure and sandwiched optical waveguide

• US 7,868,542 B2
• Filed: 02/08/2008
• Issued: 01/11/2011
• Est. Priority Date: 02/09/2007
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Fukuda, Koichi
• Primary Examiner(s): Roy; Sikha
• Assistant Examiner(s): GREEN, TRACIE Y
• Application Number:
  US12/028,107
• Publication Number:
  US 20080303419A1
• Time in Patent Office: 1,068 Days
• Field of Search: 313501-512
• US Class Current: 313/506
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 50/854 comprising scattering means
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/877 comprising scattering means
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/342 comprising iridium

Abstract

Provided is a light-emitting apparatus which can improve the light extraction efficiency without adversely influencing a functional layer of a light-emitting device and which includes a substrate; a light-emitting device formed on the substrate, the light-emitting device including: a first electrode formed on the substrate; an insulating member covering a periphery of the first electrode; and a functional layer formed on an exposed portion of the first electrode and including an emission layer; and a second electrode formed on the functional layer and the insulating member, in which a periodic structure is formed on a surface of the insulating member opposite to a substrate side, and an optical waveguide is formed between a bottom portion of the periodic structure and the first electrode or between the bottom portion of the periodic structure and the substrate.

Claims

1. A light-emitting apparatus comprising:

a substrate; and

a light-emitting device formed on the substrate, the light-emitting device comprising;

a first electrode formed on the substrate;

an insulating member covering a periphery of the first electrode;

a functional layer formed on an exposed portion of the first electrode and comprising an emission layer; and

a second electrode formed on the functional layer and the insulating member,

wherein a periodic structure is formed on a surface of the insulating member opposite to a substrate side, and an optical waveguide is formed in the insulating member.

2. The light-emitting apparatus according to claim 1, wherein a period a of the periodic structure satisfies

3. The light-emitting apparatus according to claim 1, wherein a period of the periodic structure is larger than 0.25 times a peak wavelength of a spectrum of light extracted outside via the periodic structure.

4. The light-emitting apparatus according to claim 1, which comprises a light-emitting device for emitting light of red color, a light-emitting device for emitting light of green color, and a light-emitting device for emitting light of blue color, wherein a period of the periodic structure of the light-emitting device for emitting light of red color is the longest and a period of the periodic structure of the light-emitting device for emitting light of blue color is the shortest.

5. The light-emitting apparatus according to claim 1, wherein the light-emitting device is arranged in plurality in vertical and horizontal directions in an emission region, and the periodic structure of the light-emitting devices arranged in the vertical direction and the periodic structure of the light-emitting devices arranged in the horizontal direction have the same period.

6. The light-emitting apparatus according to claim 1, further comprising a black matrix on a light extraction side of the periodic structure, wherein a period a of the periodic structure satisfies the following equation:

7. The light-emitting apparatus according to claim 1, further comprising a microcavity structure in a stack direction of the light-emitting device.

8. The light-emitting apparatus according to claim 1, further comprising a color filter for transmitting light emitted from the light-emitting device on a light extraction side of the light-emitting device.

9. The light-emitting apparatus according to claim 1, further comprising a circularly polarizing plate on the light extraction side of the light-emitting device.

10. The light-emitting apparatus according to claim 1, wherein the periodic structure has a structure in which a height of the optical waveguide varies continuously in an in-plane direction of the substrate.

11. The light-emitting apparatus according to claim 1, wherein a refractive index of the insulating member and a refractive index of the second electrode are equal to each other.

12. The light-emitting apparatus according to claim 1, wherein the light-emitting device is an OLED device.

13. The light-emitting apparatus according to claim 1, wherein the optical waveguide is formed in the insulating member and between a bottom portion of the periodic structure and the first electrode or between the bottom portion of the periodic structure and the substrate.