Laser oscillator

• US 8,059,692 B2
• Filed: 02/19/2009
• Issued: 11/15/2011
• Est. Priority Date: 09/12/2003
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nomura, Ryoji, Shimomura, Akihisa
• Primary Examiner(s): Stultz; Jessica
• Assistant Examiner(s): Nguyen; Tuan N
• Application Number:
  US12/388,585
• Publication Number:
  US 20090185584A1
• Time in Patent Office: 999 Days
• Field of Search: 257/103, 428/690, 385/93
• US Class Current: 372/92
• CPC Class Codes: H01S 5/02212 Can-type, e.g. TO-CAN housings with emission along or parallel to symmetry axis
• CPC Class Codes: H01S 5/02345 Wire-bonding
• CPC Class Codes: H01S 5/04256 characterised by the configuration
• CPC Class Codes: H01S 5/04257 having positive and negative electrodes on the same side of the substrate
• CPC Class Codes: H01S 5/1039 Details on the cavity length
• CPC Class Codes: H01S 5/18388 Lenses
• CPC Class Codes: H01S 5/36 comprising organic materials
• CPC Class Codes: H01S 5/423 having a vertical cavity

Abstract

The present invention provides a laser oscillator using an electroluminescent material that can enhance directivity of emitted laser light and resistance to a physical impact. The laser oscillator has a first layer including a concave portion, a second layer formed over the first layer to cover the concave portion, and a light emitting element formed over the second layer to overlap the concave portion, wherein the second layer is planarized, an axis of laser light obtained from the light emitting element intersects with a planarized surface of the second layer, the first layer has a curved surface in the concave portion, and a refractive index of the first layer is lower than that of the second layer.

Claims

1. A laser oscillator comprising:

a light emitting element over a first layer comprising a concave portion;

a second layer that is light-transmitting and that is formed to cover the light emitting element; and

a third layer between the first layer and the light emitting element,

wherein the light emitting element comprises;

a first electrode over the first layer;

a first organic electroluminescent layer over the first electrode;

a second organic electroluminescent layer over the first organic electroluminescent layer;

a charge generation layer between the first and second organic electroluminescent layers; and

a second electrode over the second organic electroluminescent layer,

wherein a first refractive index of the first layer is lower than a second refractive index of the third layer,

wherein first light generated in the first organic electroluminescent layer and second light generated in the second organic electroluminescent layer are reflected at the first electrode and the second electrode, and

wherein the concave portion has a curve.

2. The laser oscillator according to claim 1, wherein the charge generation layer comprises molybdenum oxide.

3. The laser oscillator according to claim 1, wherein a distance between the first and second electrodes is an integral multiple of a half of a wavelength of the light.

4. The laser oscillator according to claim 1, wherein the first layer is an insulating substrate.

5. A laser oscillator comprising:

a light emitting element over a first layer comprising a concave portion;

a second layer that is light-transmitting and that is formed to cover the light emitting element; and

a third layer between the first layer and the light emitting element,

wherein the light emitting element comprises;

a first electrode over the first layer;

a first organic electroluminescent layer over the first electrode;

a second organic electroluminescent layer over the first organic electroluminescent layer;

a charge generation layer between the first and second organic electroluminescent layers; and

a second electrode over the second organic electroluminescent layer,

wherein the second layer has a curved convex portion which overlaps with the light emitting element,

wherein a first refractive index of the first layer is lower than a second refractive index of the third layer,

wherein first light generated in the first organic electroluminescent layer and second light generated in the second organic electroluminescent layer are reflected at the first electrode and the second electrode, and

wherein the concave portion has a curve.

6. The laser oscillator according to claim 5, wherein the charge generation layer comprises molybdenum oxide.

7. The laser oscillator according to claim 5, wherein a distance between the first and second electrodes is an integral multiple of a half of a wavelength of the light.

8. The laser oscillator according to claim 5, wherein the second layer comprises polymeric material.

9. The laser oscillator according to claim 5, wherein the first layer is an insulating substrate.

10. A laser oscillator comprising:

a reflective film over a first layer comprising a concave portion;

a light emitting element over the reflective film;

a third layer between the reflective film and the light emitting element; and

a second layer that is light-transmitting and that is formed to cover the light emitting element,

wherein the light emitting element comprises;

a first electrode over the first layer;

a first organic electroluminescent layer over the first electrode;

a second organic electroluminescent layer over the first organic electroluminescent layer;

a charge generation layer between the first and second organic electroluminescent layers; and

a second electrode over the second organic electroluminescent layer,

wherein the second layer has a curved convex portion which overlaps with the light emitting element,

wherein a first refractive index of the first layer is lower than a second refractive index of the third layer,

wherein first light generated in the first organic electroluminescent layer and second light generated in the second organic electroluminescent layer are reflected at the first electrode and the second electrode, and

wherein the concave portion has a curve.

11. The laser oscillator according to claim 10, wherein the charge generation layer comprises molybdenum oxide.

12. The laser oscillator according to claim 10, wherein a distance between the first and second electrodes is an integral multiple of a half of a wavelength of the light.

13. The laser oscillator according to claim 10, wherein the second layer comprises polymeric material.

14. The laser oscillator according to claim 10, wherein the first layer is an insulating substrate.