Planar optical waveguide device

A planar optical waveguide device comprising:

• a substrate having a first coefficient of thermal expansion;
• a lower cladding layer formed on said substrate, said lower cladding layer having a second coefficient of thermal expansion smaller than said first coefficient of thermal expansion;
• a core formed on said lower cladding layer;
• a plurality of dummy cores formed on said lower cladding layer on the opposite sides of said core;
• an upper cladding layer formed on said lower cladding layer so as to cover said core and said dummy cores, said upper cladding layer having said second coefficient of thermal expansion, said upper cladding layer having a plurality of projections respectively corresponding to said core and said dummy cores;
• and
• a contraction material fixed to said upper cladding layer so as to cover a part of said projections corresponding to said dummy cores on each side of said core.

A planar optical waveguide device comprising:

• a substrate having a first coefficient of thermal expansion;
• a lower cladding layer formed on said substrate, said lower cladding layer having a second coefficient of thermal expansion smaller than said first coefficient of thermal expansion;
• a core formed on said lower cladding layer;
• an upper cladding layer formed on said lower cladding layer so as to cover said core, said upper cladding layer having said second coefficient of thermal expansion;
• a plurality of grooves formed in said upper and lower cladding layers on the opposite sides of said core so as to extend along said core;
• a piezoelectric material filling each of said plurality of grooves and fixed to said upper and lower cladding layers;
• and
• means for applying a voltage to said piezoelectric material.

A planar optical waveguide device comprising:

• a substrate having a first coefficient of thermal expansion;
• a lower cladding layer formed on said substrate, said lower cladding layer having a second coefficient of thermal expansion larger than said first coefficient of thermal expansion;
• a core formed on said lower cladding layer;
• an upper cladding layer formed on said lower cladding layer so as to cover said core, said upper cladding layer having said second coefficient of thermal expansion;
• a plurality of grooves formed in said upper and lower cladding layers on the opposite sides of said core so as to extend along said core;
• a thermal expansion material filling each of said plurality of grooves;
• and
• a temperature controller mounted on said thermal expansion material.

A planar optical waveguide device comprising:

• a substrate having a first coefficient of thermal expansion;
• a lower cladding layer formed on said substrate, said lower cladding layer having a second coefficient of thermal expansion larger than said first coefficient of thermal expansion;
• a core formed on said lower cladding layer;
• an upper cladding layer formed on said lower cladding layer so as to cover said core, said upper cladding layer having said second coefficient of thermal expansion;
• a plurality of grooves formed in said upper and lower cladding layers on the opposite sides of said core so as to extend along said core;
• and
• a thermal expansion material filling each of said plurality of grooves, said thermal expansion material having a third coefficient of thermal expansion smaller than said second coefficient of thermal expansion.

A planar optical waveguide device comprising:

• a substrate having a first coefficient of thermal expansion;
• a lower cladding layer formed on said substrate, said lower cladding layer having a second coefficient of thermal expansion larger than said first coefficient of thermal expansion;
• a core formed on said lower cladding layer;
• an upper cladding layer formed on said lower cladding layer so as to cover said core, said upper cladding layer having said second coefficient of thermal expansion;
• a plurality of grooves formed in said upper and lower cladding layers on the opposite sides of said core so as to extend along said core;
• a piezoelectric material filling each of said plurality of grooves;
• and
• means for applying a voltage to said piezoelectric material.