Optical waveguide device, optical transmitting and receiving device, method of manufacturing optical waveguide device and method of manufacturing optical transmitting and receiving device

An optical transmitting and receiving device comprising:

• an optical waveguide formed on a substrate and enabling a light to bidirectionally propagate therethrough;
• a trench-shaped space formed in the optical waveguide near at least one end of the optical waveguide to cross the direction of light propagation, the trench-shaped space being capable of switching the light propagating through the optical waveguide;
• a photodetector for receiving a coming light switched by the trench-shaped space;
• and
• a light emitting device for emitting a transmitting light toward the trench-shaped space,
• wherein the trench-shaped space has a first boundary surface capable of internally reflecting the coming light propagating through the optical waveguide, thereby guiding the coming light out of the optical waveguide, and a second boundary surface capable of passing therethrough the transmitting light traveling in the direction opposite to the direction of propagation of the coming light, thereby guiding the transmitting light into the optical waveguide,
• wherein when n denotes a refractive index of a material constituting a principal part of the optical waveguide,
• an angle θ1(°) of the first boundary surface to the direction of light propagation and an angle θ2(°) of the second boundary surface to the direction of light propagation satisfy the following expressions:
• θ1<90-sin−1(1/n)
• θ2>90-sin−1(1/n).

A method of manufacturing an optical waveguide device comprising the steps of:

• forming on a substrate an optical waveguide enabling a light to bidirectionally propagate therethrough;
• and
• forming a trench-shaped space in the optical waveguide near at least one end of the optical waveguide to cross the direction of light propagation, the trench-shaped space having a first boundary surface and a second boundary surface, the first boundary surface being capable of internally reflecting a coming light propagating through the optical waveguide and thereby guiding outward the coming light through the upper surface or the side surface of the optical waveguide, the second boundary surface being capable of passing therethrough a transmitting light traveling in the direction opposite to the direction of propagation of the coming light and thereby guiding the transmitting light into the optical waveguide through the first boundary surface,
• wherein when n denotes a refractive index of a material constituting a principal part of the optical waveguide,
• an angle θ1(°) of the first boundary surface to the direction of light propagation and an angle θ2(°) of the second boundary surface to the direction of light propagation satisfy the following expressions:
• θ1<90-sin−1(1/n)
• θ2>90-sin−1(1/n).

A method of manufacturing an optical transmitting and receiving device comprising the steps of:

• forming on a substrate, an optical waveguide enabling a light to bidirectionally propagate therethrough;
• forming a trench-shaped space in the optical waveguide near at least one end of the optical waveguide to cross the direction of light propagation, the trench-shaped space having a first boundary surface and a second boundary surface, the first boundary surface being capable of internally reflecting a coming light propagating through the optical waveguide and thereby guiding outward the coming light through the upper surface or the side surface of the optical waveguide, the second boundary surface being capable of passing therethrough a transmitting light traveling in the direction opposite to the direction of propagation of the coming light and thereby guiding the transmitting light to the optical waveguide through the first boundary surface;
• forming a photodetector for receiving the coming light reflected by the first boundary surface, on the upper surface or the side surface of the optical waveguide near the first boundary surface;
• and
• forming near the end surface a light emitting device for emitting the transmitting light toward the end surface,
• wherein when n denotes a refractive index of a material constituting a principal part of the optical waveguide,
• an angle θ1(°) of the first boundary surface to the direction of light propagation and an angle θ2(°) of the second boundary surface to the direction of light propagation satisfy the following expressions:
• θ1<90-sin−1(1/n)
• θ2>90-sin−1(1/n).