Optical Circuit Chips
An optical circuit chip including an optical circuit connected to a fiber array is provided. At this time, an optical chip includes a substrate including a high refractive index layer, a low refractive index layer having a lower refractive index than the high refractive index layer, a lower cladding layer, and an upper cladding layer including the high refractive index layer and the low refractive index layer and having a lower refractive index than the low refractive index layer; a high refractive index core connected to an optical circuit formed in the high refractive index layer, low refractive index cores formed in the low refractive index layer and connected to the high refractive index core; and at least a pair of alignment waveguides formed in the low refractive index layer and having one end portion connected to an end surface of the substrate facing the fiber array.
1 . An optical circuit chip that includes an optical circuit connected to a fiber array, the optical circuit chip comprising:
a substrate including a first layer, a second layer having a lower refractive index than the first layer, and a third layer including the first layer and the second layer and having a lower refractive index than the second layer;
a first optical waveguide connected to the optical circuit formed in the first layer;
a second optical waveguide formed in the second layer and connected to the first optical waveguide; and
at least a pair of alignment waveguides formed in the second layer and having one end portion connected to an end surface of the substrate facing the fiber array.
2 . The optical circuit chip according to claim 1 , wherein the other end portions of the pair of alignment waveguides are connected to each other in the second layer.
3 . The optical circuit chip according to claim 1 , wherein the other end portion of the alignment waveguide is connected to a reflection circuit.
4 . The optical circuit chip according to claim 2 , comprising: two pairs of the alignment waveguides, wherein the fiber array is connected at a center between a relative position with respect to the fiber array determined in one pair of the alignment waveguides and a relative position with respect to the fiber array determined in the other pair of the alignment waveguides.
5 . The optical circuit chip according to claim 2 , wherein the fiber array has a plurality of optical fibers, and a spacing between a pair of the alignment waveguides is equal to a spacing between two arbitrary optical fibers among the plurality of optical fibers.
6 . The optical circuit chip according to claim 1 , wherein the first layer includes silicon.