Light emitting device and projector

Patent metadata

Field	Value
Publication number	US-2016190386-A1
Application number	US-201514757410-A
Country	US
Kind code	A1
Filing date	Dec 23, 2015
Priority date	Dec 24, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

In a light emitting device, a light waveguide is provided with a first region including a central position, a second region including a first light emission surface, and a third region including a second light emission surface. A second cladding layer includes a plurality of noncontact regions. The plurality of noncontact regions intersect the light waveguide. A ratio of an area in which the plurality of noncontact regions overlap the first region to an area of the first region is greater than a ratio of an area in which the plurality of noncontact regions overlap the second region to an area of the second region, and is greater than a ratio of an area in which the plurality of noncontact regions overlap the third region to an area of the third region.

First claim

What is claimed is:

1 . A light emitting device comprising:
an active layer configured to generate light in correspondence with a current injected thereinto; a first cladding layer and a second cladding layer sandwiching the active layer therebetween; and a first electrode and a second electrode configured to inject the current into the active layer, wherein the active layer constitutes a light waveguide through which the light is guided, wherein the light waveguide is provided with:
a first light emission surface and a second light emission surface from which the light is emitted;
a first region including a midpoint that is equidistant from the first light emission surface and the second light emission surface;
a second region including the first light emission surface; and
a third region including the second light emission surface,
wherein the second cladding layer includes a plurality of noncontact regions that are not electrically connected to the second electrode, wherein the plurality of noncontact regions intersect the light waveguide in a plan view, and wherein, in the plan view, a ratio of an area in which the plurality of noncontact regions overlap the first region to an area of the first region is greater than a ratio of an area in which the plurality of noncontact regions overlap the second region to an area of the second region, and is greater than a ratio of an area in which the plurality of noncontact regions overlap the third region to an area of the third region.

2 . The light emitting device according to claim 1 , further comprising:
a contact layer that is provided between the second cladding layer and the second electrode, wherein the contact layer is not provided in the plurality of noncontact regions.

3 . The light emitting device according to claim 1 ,
wherein the plurality of noncontact regions only intersect the first region in the plan view.

4 . The light emitting device according to claim 1 ,
wherein pitches of the plurality of noncontact regions gradually increase toward the first light emission surface and the second light emission surface from the midpoint.

5 . The light emitting device according to claim 1 ,
wherein, in the plan view, pitches of the plurality of noncontact regions overlapping the first region are equal to each other, pitches of the plurality of noncontact regions overlapping the second region gradually increase toward the first light emission surface from the midpoint, and pitches of the plurality of noncontact regions overlapping the third region gradually increase toward the second light emission surface from the midpoint.

6 . The light emitting device according to claim 1 ,
wherein a length of the first region in an extending direction of the light waveguide is L/4 or more and 3L/4 or less, wherein L is a length of the light waveguide in the extending direction between the first light emission surface and the second light emission surface.

7 . The light emitting device according to claim 1 ,
wherein the light waveguide extends in a tilted direction with respect to a normal line of the first light emission surface and a normal line of the second light emission surface.

8 . A projector comprising:
the light emitting device according to claim 1 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

9 . A projector comprising:
the light emitting device according to claim 2 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

10 . A projector comprising:
the light emitting device according to claim 3 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

11 . A projector comprising:
the light emitting device according to claim 4 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

12 . A projector comprising:
the light emitting device according to claim 5 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

13 . A projector comprising:
the light emitting device according to claim 6 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

14 . A projector comprising:
the light emitting device according to claim 7 ; a light modulation device configured to modulate the light emitted from the light emitting device according to image information; and a projection device configured to project an image formed by the light modulation device.

Assignees

• Seiko Epson Corp

Inventors

• Nishioka Hiroki

Classifications

• H10H20/81

  Bodies · CPC title

• H10H20/816

  having carrier transport control structures, e.g. highly-doped semiconductor layers or current-blocking structures · CPC title

• H10H20/814

  having reflecting means, e.g. semiconductor Bragg reflectors · CPC title

• H10H20/83

  Electrodes · CPC title

• H10H20/042 Primary

  Superluminescent diodes · CPC title