SPOT SIZE CONVERTER AND OPTICAL APPARATUS

• US 20150117818A1
• Filed: 09/17/2014
• Published: 04/30/2015
• Est. Priority Date: 10/25/2013
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Matsumoto, Takeshi, Sekiguchi, Shigeaki
• Application Number:
  US14/488,727
• Publication Number:
  US 20150117818A1
• Time in Patent Office: Days
• US Class Current: 385/43
• CPC Class Codes: G02B 2006/12061 Silicon
• CPC Class Codes: G02B 6/305 and having an integrated mode-size expanding section, e.g. tapered waveguide

Abstract

A spot size converter includes a first silicon waveguide core that includes a width-fixed region having a fixed width and a width-tapered region continuing to the width-fixed region and having a width reducing toward a terminal portion, and a second waveguide core continuing to the first silicon waveguide core and covering at least the width-tapered region. The first silicon waveguide core has a thickness-wise step in the width-fixed region.

Claims

1. A spot size converter, comprising:

a first silicon waveguide core that includes a width-fixed region having a fixed width and a width-tapered region continuing to the width-fixed region and having a width reducing toward a terminal portion; and

a second waveguide core continuing to the first silicon waveguide core and covering at least the width-tapered region;

wherein

the first silicon waveguide core has a thickness-wise step in the width-fixed region.

2. The spot size converter according to claim 1, wherein the second waveguide core partially covers the width-fixed region;

and

the step is provided at an end face position of a side covering the width-fixed region of the second waveguide core.

3. The spot size converter according to claim 1, wherein the first silicon waveguide core is a channel structure silicon waveguide core;

the spot size converter further comprising a rib structure silicon waveguide core that continues to a side opposite to the width-tapered region across the width-fixed region;

the step being provided at a boundary position between the channel structure silicon waveguide core and the rib structure silicon waveguide core.

4. The spot size converter according to claim 1, wherein the second waveguide core partially covets the width-fixed region;

and

the first silicon waveguide core is a channel, structure silicon waveguide core;

the spot size converter further comprising a rib structure silicon waveguide core that continues to the opposite side to the width-tapered region across the width-fixed region;

the step including a first step provided at a position other than an end face position of a side covering the width-fixed region of the second waveguide core and a second step provided at a boundary position between the channel structure silicon waveguide core end the rip structure silicon waveguide core.

5. The spot size converter according to claim 1, wherein the second waveguide partially covers the width-fixed portion;

and

the first silicon waveguide core is a channel structure silicon waveguide core;

the spot size converter further comprising a rib structure silicon waveguide core that continues to a side opposite to the width-tapered region across the width-fixed region;

the step including a third step provided at an end face position of a side covering the width-fixed region of the second waveguide core and a fourth step provided at a boundary position between the channel structure silicon waveguide core and the rib structure silicon waveguide core.

6. The spot size converter according to claim 1, wherein the stop is provided at a plurality of locations of the width-fixed region.

7. The spot size converter according to claim 1, wherein the step is provided obliquely to a direction orthogonal to an extending direction of the width-fixed region.

8. An optical apparatus, comprising:

the spot size converter including a first silicon waveguide core that includes a width-fixed region having a fixed width and a width-tapered region continuing to the width-fixed region and having a width reducing toward a terminal portion, and a second waveguide core continuing to the first silicon waveguide core and covering at least the width-tapered region, the first silicon waveguide core having a thickness-wise step in the width-fixed region; and

a dispersion shift fiber or a single-mode fiber coupled to an end face on a side of the second waveguide core of the spot size converter.

9. The optical apparatus according to claim 8, wherein the second waveguide core partially covers the width-fixed region;

and

the step is provided at an end face position of a side covering the width-fixed region of the second waveguide core.

10. The optical apparatus according to claim 8, wherein the first silicon waveguide core is a channel structure silicon waveguide core;

the spot size converter further comprising a rib structure silicon waveguide core that continues to a side opposite to the width-tapered region across the width-fixed region;

the step being provided at a boundary position between the channel structure silicon waveguide core and the rib structure silicon waveguide core.

11. The optical apparatus according to claim 8, wherein the second waveguide core partially covers the width-fixed region;

and

the first silicon waveguide core is a channel structure silicon waveguide core;

the spot size converter further comprising a rib structure silicon waveguide core that continues to the opposite side to the width-tapered region across the width-fixed region;

the step including a first step provided at a position other than an end face position of a side covering the width-fixed region of the second waveguide core and a second step provided at a boundary position between the channel structure silicon waveguide core and the rib structure silicon waveguide core.

12. The optical apparatus according to claim 8, wherein the second waveguide core partially covers the width-fixed portion;

and

the first silicon waveguide core is a channel structure silicon waveguide core;

the spot, size converter further comprising a rib structure silicon waveguide core that continues to a side opposite to the width-tapered region across the width-fixed region;

the step including a third step provided at an end face position of a side covering the width-fixed region of the second waveguide core and a fourth step provided at a boundary position between the channel structure silicon waveguide core and the rib structure silicon waveguide core.

13. The optical apparatus according to claim 8, wherein the step is provided at a plurality of locations of the width-fixed region.

14. The optical apparatus according to claim 8, wherein the step is provided obliquely to a direction orthogonal to an extending direction of the width-fixed region.