Integrated optical circuit with traversing attentuation zone

Patent metadata

Field	Value
Publication number	US-9239430-B2
Application number	US-201314372768-A
Country	US
Kind code	B2
Filing date	Jan 16, 2013
Priority date	Jan 19, 2012
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

An integrated optical circuit includes an optically transparent substrate including: an input face, an output face, an upper face and a lower face, the upper and lower faces extending between the input and output faces; at least one optical waveguide which includes at least one first end situated on the input face and a second end situated on the output face; and at least one optical attenuation zone able to attenuate an optical signal transmitted via the substrate to the outside of the waveguide. The waveguide has a non-rectilinear optical path between the first and second end, the attenuation zone extends from the upper face to the lower face, and is positioned on a straight line segment joining the first and second end of the optical waveguide, the waveguide and the attenuation zone having respective dimensions such that the attenuation zone does not cut the waveguide.

First claim

The invention claimed is:

1. An integrated optical circuit comprising:
an optically transparent substrate comprising:
an input face, an output face, two lateral faces, a lower face, and an upper face, said lower face and said upper face extending between the input face and the output face, the upper face being planar and opposite to the lower face,
at least one optical waveguide located in a plane parallel to the upper face,
at least one first waveguide end located on the input face of the substrate and at least one second waveguide end located on the output face of the substrate, and
at least one optical attenuation zone configured to attenuate an optical beam transmitted via the substrate in a non-guided manner by said optical waveguide,

wherein said at least one waveguide has a non-rectilinear optical path between said at least one first waveguide end and said at least one second waveguide end,
a straight line segment is defined between said at least one first waveguide end and said at least one second waveguide end, said at least one attenuation zone extending inside the substrate from the lower face to the upper face of the substrate, said at least one attenuation zone being positioned on said straight line segment so as to attenuate a non-guided optical beam transmitted via the substrate between said first waveguide end and said second waveguide end,
said at least one waveguide and said at least one attenuation zone have respective dimensions such that said at least one attenuation zone does not cut said waveguide, and
said at least one attenuation zone has such dimensions that a straight line passing through said first waveguide end and tangent to said at least one attenuation zone has a point of intersection with the output face located at a minimum distance x from said second waveguide end, such that the distance x is higher than or equal to:

D
⁢

⁢
λ

2

where D is the distance between said attenuation zone and said point of intersection, and λ is the wavelength in the material of said non-guided optical beam.

2. The integrated optical circuit according to claim 1 , wherein said at least one optical attenuation zone comprises at least one through-hole extending from the lower face to the upper face of the substrate.

3. The integrated optical circuit according to claim 2 , wherein said at least one through-hole is filled with an optically absorbing or opaque material or a reflective material.

4. The integrated optical circuit according to claim 1 , wherein said at least one optical attenuation zone is positioned in the middle of said straight line segment joining a first waveguide end on the input face of the integrated optical circuit and a second waveguide end on the output face of the integrated optical circuit.

5. The integrated optical circuit according to claim 1 , wherein said at least one waveguide is configured to guide an optical beam having a first, guided, determined state of polarization and to transmit in the substrate a non-guided optical beam having a second state of polarization.

6. The integrated optical circuit according to claim 1 , further comprising at least one first groove on the lower face of the integrated optical circuit, one second groove on the upper face of the integrated optical circuit, and/or one third groove on the lateral face of the integrated optical circuit.

7. The integrated optical circuit according to claim 1 , wherein said at least one optical waveguide comprises a common branch, a first secondary branch, and a second secondary branch, the common branch being connected by a Y-junction to the first secondary branch and to the second secondary branch, said at least one attenuation zone being arranged on a first straight line segment joining the first end of the common branch on the input face to the second end of the first secondary branch on the output face and/or on a second straight line segment joining the first end of the common branch on the input face to the second end of the second secondary branch on the output face.

8. The integrated optical circuit according to claim 7 , wherein said at least one attenuation zone comprises at least one first attenuation zone and at least one second attenuation zone, said first attenuation zone being arranged on a first straight line segment joining the first end of the common branch on the input face to the second end of the first secondary branch on the output face and said second attenuation zone being arranged on a second straight line segment joining the first end of the common branch on the input face to the second end of the second secondary branch on the output face.

9. The integrated optical circuit according to claim 8 , wherein said first attenuation zone and said second attenuation zone are arranged respectively on either side of the common branch of the Y-junction.

10. The integrated optical circuit according to claim 1 , wherein said substrate comprises N optical waveguides N being an integer higher than or equal to two, having at least N waveguide ends on the input face and/or at least N waveguide ends on the output face, and said at least one attenuation zone comprises at least N distinct attenuation zones, each distinct attenuation zone being arranged on a straight line segment joining a waveguide end on the input face and a waveguide end on the output face.

11. The integrated optical circuit according to claim 1 , wherein said substrate comprises at least one additional attenuation zone extending inside the substrate from the lower face to the upper face of the substrate, said at least one additional attenuation zone being positioned in such a manner to attenuate a non-guided optical beam following an optical path comprising a reflection on a lateral face and a reflection on the lower face between said first waveguide end and said second waveguide end.

12. An integrated optical circuit comprising:
an optically transparent substrate comprising:
an input face, an output face, two lateral faces, a lower face, and an upper face, said lower face and said upper face extending between the input face and the output face, the upper face being planar and opposite to the lower face,
at least one optical waveguide located in a plane parallel to the upper face,
at least one first waveguide end located on the input face of the substrate and at least one second waveguide end located on the output face of the substrate, and
at least one optical attenuation zone configured to attenuate an optical beam transmitted via the substrate in a non-guided manner by said optical waveguide,

wherein said at least one waveguide has a non-rectilinear optical path between said at least one first waveguide end and said at least one second waveguide end,
a straight line segment is defined between said at least one first waveguide end and said at least one second waveguide end, said at least one attenuation zone extending inside the substrate from the lower face to the upper face of the substrate, said at least one attenuation zone being positioned on said straight line segment so as to attenuate a non-guided optical beam transmitted via the substrate between said first waveguide end and said second waveguide end,
said at least one waveguide and said at least one attenuation zone have respective dimensions such that said at least one attenuation zone does not cut said waveguide, a

Assignees

• Lefevre Herve Claude
• Guattari Frederic
• Ixblue

Inventors

• Lefevre Herve Claude
• Guattari Frederic

Classifications

• G02B2006/1215

  Splitter · CPC title

• G02B6/12

  of the integrated circuit kind (electric integrated circuits H10B, H10D84/00 - H10D89/00, H10F19/00, H10F39/00, H10H29/00, H10K19/00, H10K39/00, H10K59/00, H10N19/00, H10N39/00, H10N59/00, H10N69/00, H10N79/00, H10N89/00) · CPC title

• G02B6/122

  Basic optical elements, e.g. light-guiding paths · CPC title

• G02B6/30

  for use between fibre and thin-film device · CPC title

• G02B6/266 Primary

  the optical element being an attenuator · CPC title