In one example embodiment, an integrated silicon photonic wavelength division demultiplexer includes an input waveguide, an input port, a plurality of output waveguides, a plurality of output ports, a first auxiliary waveguide, and a plurality of auxiliary waveguides. The input waveguide may be formed in a first layer and having a first effective index n1. The input port may be optically coupled to the input waveguide. The output waveguides may be formed in the first layer and may have the first effective index n1. Each of the output ports may be optically coupled to a corresponding output waveguide. The first auxiliary waveguide may be formed in a second layer below the input waveguide in the first layer. The first auxiliary waveguide may have a second effective index n2 and may have two tapered ends, and n2 may be higher than n1.

A spot-size converter for coupling light between a first waveguide and a second waveguide extends along a longitudinal waveguiding axis and includes a transition region. The transition region includes a first part of waveguiding structure, which is coupled to the first waveguide, and a second part of waveguiding structure, which is coupled to the second waveguide. The second part of waveguiding structure includes high-index elements arranged in multiple vertically spaced rows and horizontally spaced columns, and extends along the longitudinal waveguiding axis at least partially over the first part of waveguiding structure so as to define a low-index region where the mode of the first waveguide progressively transforms into the mode of the second waveguide, thereby enabling light propagation via a mode of the combined system of the first and second parts of waveguiding structures.

A spot-size converter for coupling light between a first waveguide and a second waveguide extends along a longitudinal waveguiding axis and includes a transition region. The transition region includes a first part of waveguiding structure, which is coupled to the first waveguide, and a second part of waveguiding structure, which is coupled to the second waveguide. The second part of waveguiding structure includes high-index elements arranged in multiple vertically spaced rows and horizontally spaced columns, and extends along the longitudinal waveguiding axis at least partially over the first part of waveguiding structure so as to define a low-index region where the mode of the first waveguide progressively transforms into the mode of the second waveguide, thereby enabling light propagation via a mode of the combined system of the first and second parts of waveguiding structures.

An optical deflection device that achieve both high beam quality and wide angular range of deflection and compatibility with an optical integration technology of silicon photonics. The optical deflection device is a silicon photonics device including a periodic structure of a refractive index. The optical deflection device includes two configurations, which are (1) a configuration in which an optical propagation part where light propagates is a microstructure formed on silicon, and (2) a configuration in which the microstructure constituting the optical propagation part includes a periodic structure that generates slow light and a periodic structure that radiates light. The microstructure formed on the silicon of (1) makes it possible to employ the optical integration technology of silicon photonics and form the optical deflection device. The two periodic structures of (2) make it possible to form a light beam with high beam quality and a wide angular range of deflection.

An optical deflection device that achieve both high beam quality and wide angular range of deflection and compatibility with an optical integration technology of silicon photonics. The optical deflection device is a silicon photonics device including a periodic structure of a refractive index. The optical deflection device includes two configurations, which are (1) a configuration in which an optical propagation part where light propagates is a microstructure formed on silicon, and (2) a configuration in which the microstructure constituting the optical propagation part includes a periodic structure that generates slow light and a periodic structure that radiates light. The microstructure formed on the silicon of (1) makes it possible to employ the optical integration technology of silicon photonics and form the optical deflection device. The two periodic structures of (2) make it possible to form a light beam with high beam quality and a wide angular range of deflection.

An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

The visual detection of a silicon optical circuit in a conventional technique depends on sensory decision by a human who visually conducts checking, and there has been limitation in completely detecting small flaws. The optical circuit of the present invention includes, in addition to an optical circuit that implements desired functions, an optical waveguide for flaw detection which surrounds the entire optical circuit and which is sufficiently proximate to the optical waveguide of the optical circuit and grating couplers connected to the optical waveguide for detection. Based on the transmission characteristic measurement of the optical waveguide for detection using the grating couplers, a flaw within each chip can be efficiently discovered in the state of a wafer before being cut into chips. A flaw can also be discovered hierarchically by providing individual optical waveguides for detection for respective chips and by further forming one common optical waveguide for detection over the plurality of chips.

The visual detection of a silicon optical circuit in a conventional technique depends on sensory decision by a human who visually conducts checking, and there has been limitation in completely detecting small flaws. The optical circuit of the present invention includes, in addition to an optical circuit that implements desired functions, an optical waveguide for flaw detection which surrounds the entire optical circuit and which is sufficiently proximate to the optical waveguide of the optical circuit and grating couplers connected to the optical waveguide for detection. Based on the transmission characteristic measurement of the optical waveguide for detection using the grating couplers, a flaw within each chip can be efficiently discovered in the state of a wafer before being cut into chips. A flaw can also be discovered hierarchically by providing individual optical waveguides for detection for respective chips and by further forming one common optical waveguide for detection over the plurality of chips.

A structure for coupling an optical signal between an integrated circuit photonic structure and an external optical fiber is disclosed as in a method of formation. The coupling structure is sloped relative to a horizontal surface of the photonic structure such that light entering or leaving the photonic structure is substantially normal to its upper surface.

A structure for coupling an optical signal between an integrated circuit photonic structure and an external optical fiber is disclosed as in a method of formation. The coupling structure is sloped relative to a horizontal surface of the photonic structure such that light entering or leaving the photonic structure is substantially normal to its upper surface.