Waveguide-type optical control device and process for producing the same

A waveguide-type optical control device comprising:

• a phase shifter provided with a first electrode section comprising an electrode provided on the left side of a left optical waveguide, an electrode provided on the right side of a right optical waveguide, and an electrode provided between the two optical waveguides;
• and
• a directional coupler comprising two optical waveguides which are connected respectively to the two right and left optical waveguides in the phase shifter and are provided parallel to each other with the spacing between the two optical waveguides being partially reduced, said directional coupler being used in at least one of an optical branching section provided on the input side of the phase shifter and an optical coupling section provided on the output side of the phase shifter, the refractive index of the two optical waveguides being varied according to a voltage applied across the electrodes provided respectively on the left side of the left optical waveguide and the right side of the right optical waveguide and the electrode provided between the two optical waveguides in the phase shifter,
• said directional coupler being provided with a second electrode section comprising an electrode provided on the left side of the left optical waveguide, an electrode provided on the right side of the right optical waveguide, and an electrode provided between the two optical waveguides, the three electrodes constituting the second electrode section being electrically connected respectively to the three electrodes constituting the first electrode section provided adjacent to the second electrode section in the longitudinal direction of the two optical waveguides, the voltage applied to the first electrode section being applied to the second electrode section.

A waveguide-type optical control device comprising:

• a phase shifter comprising two left and right optical waveguides, a first electrode provided on the left side of the left optical waveguide, a second electrode provided on the right side of the right optical waveguide, and a third electrode provided between the two optical waveguides;
• a first directional coupler that is connected to one end of the phase shifter and functions to branch an optical signal introduced through one of the two optical waveguides into optical signal parts which are then introduced respectively into the two optical waveguides;
• and
• a second directional coupler that is connected to the other end of the phase shifter and functions to couple the optical signal parts received respectively from the two optical waveguides,
• at least one of the first and second electrodes and the third electrode having been extended into a part or the whole of the first directional coupler or the second directional coupler.

A waveguide-type optical control device comprising:

• a phase shifter comprising two left and right optical waveguides, a first electrode provided on the left side of the left optical waveguide, a second electrode provided on the right side of the right optical waveguide, and a third electrode provided between the two optical waveguides;
• a first directional coupler that is connected to one end of the phase shifter and functions to branch an optical signal introduced through one of the two optical waveguides into optical signal parts which are then introduced respectively into the two optical waveguides;
• and
• a second directional coupler that is connected to the other end of the phase shifter and functions to couple the optical signal parts received respectively from the two optical waveguides,
• at least one of the first and second electrodes and the third electrode having been extended into a part or the whole of the first directional coupler, at least one of the first and second electrodes and the third electrode having been extended into a part or the whole of the second directional coupler.

A waveguide-type optical control device comprising:

• a phase shifter comprising two left and right optical waveguides, a first electrode provided on the left side of the left optical waveguide, a second electrode provided on the right side of the right optical waveguide, and a third electrode provided between the two optical waveguides;
• a first directional coupler that is connected to one end of the phase shifter and functions to branch an optical signal introduced through one of the two optical waveguides into optical signal parts which are then introduced respectively into the two optical waveguides;
• and
• a second directional coupler that is connected to the other end of the phase shifter and functions to couple the optical signal parts received respectively from the two optical waveguides,
• said first directional coupler comprising, in its directional coupling section, second directional coupling section outer electrodes disposed respectively at a portion near the left side of the left optical waveguide and at a portion near the right side of the right optical waveguide in the first directional coupling section and a first directional coupling section intermediate electrode disposed between the two optical waveguides in the first directional coupling section,
• said first electrode and said second electrode having been electrically connected respectively to the first directional coupling section outer electrodes, said third electrode having been electrically connected to the first directional coupling section intermediate electrode.

A waveguide-type optical control device comprising:

• a phase shifter comprising two left and right optical waveguides, a first electrode provided on the left side of the left optical waveguide, a second electrode provided on the right side of the right optical waveguide, and a third electrode provided between the two optical waveguides;
• a first directional coupler that is connected to one end of the phase shifter and functions to branch an optical signal introduced through one of the two optical waveguides into optical signal parts which are then introduced respectively into the two optical waveguides;
• and
• a second directional coupler that is connected to the other end of the phase shifter and functions to couple the optical signal parts received respectively from the two optical waveguides,
• said second directional coupler comprising, in its directional coupling section, second directional coupling section outer electrodes disposed respectively at a portion near the left side of the left optical waveguide and at a portion near the right side of the right optical waveguide in the second directional coupling section and a second directional coupling section intermediate electrode disposed between the two optical waveguides in the second directional coupling section,
• said first electrode and said second electrode having been electrically connected respectively to the second directional coupling section outer electrodes, said third electrode having been electrically connected to the second directional coupling section intermediate electrode.

A waveguide-type optical control device comprising:

• a phase shifter comprising two left and right optical waveguides, a first electrode provided on the left side of the left optical waveguide, a second electrode provided on the right side of the right optical waveguide, and a third electrode provided between the two optical waveguides;
• a first directional coupler that is connected to one end of the phase shifter and functions to branch an optical signal introduced through one of the two optical waveguides into optical signal parts which are then introduced respectively into the two optical waveguides;
• and
• a second directional coupler that is connected to the other end of the phase shifter and functions to couple the optical signal parts received respectively from the two optical waveguides,
• at least one of the first and second electrodes and the third electrode having been extended into a part or the whole of the first directional coupler or the second directional coupler, the third electrode in its extended electrode portion being provided so that a longitudinal electric field is applied to one of the two optical waveguides.