The present invention implements an optical spectral shaper that is compact even if a number of input/output ports increases. The present invention provides a spatial light modulator, including: an optical waveguide front end that includes an input side waveguide portion which emits each signal light at a different angle while expanding a beam diameter of the signal light, and an output side waveguide portion that wave-guides each of the inputted signal lights, and couples the signal lights with a plurality of output fibers respectively; a spatial light modulator that changes the phase of each signal light by controlling the phase pattern of the plurality of pixels and emits the signal light, and the spatial light modulator in which a specific phase pattern is set for each pixel region to which each signal light enters; and an optical element group that is disposed so that each of the signal lights emitted from the optical waveguide front end is collected at a different pixel position on the spatial light modulator, and the light emitted from the spatial light modulator is coupled with the optical waveguide front end.

Apparatus and method are disclosed for co-aligning laterally displaced radiation beams from respective radiation source outputs, each beam comprising a number of spectral components. The apparatus comprises a collimating element for receiving each of said radiation beams with respective lateral displacements and a combining element for receiving each of said radiation beams passed by said collimating element for co-aligning the radiation beams. The apparatus further comprises a diffraction assembly disposed in an optical path between the output of at least one radiation source and the collimating element, for spatially separating the radiation beam output by said at least one radiation source into the constituent spectral components of radiation prior to passing the radiation to the collimating element.

The present invention implements an optical spectral shaper that is compact even if a number of input/output ports increases. The present invention provides a spatial light modulator, including: an optical waveguide front end that includes an input side waveguide portion which emits each signal light at a different angle while expanding a beam diameter of the signal light, and an output side waveguide portion that wave-guides each of the inputted signal lights, and couples the signal lights with a plurality of output fibers respectively; a spatial light modulator that changes the phase of each signal light by controlling the phase pattern of the plurality of pixels and emits the signal light, and the spatial light modulator in which a specific phase pattern is set for each pixel region to which each signal light enters; and an optical element group that is disposed so that each of the signal lights emitted from the optical waveguide front end is collected at a different pixel position on the spatial light modulator, and the light emitted from the spatial light modulator is coupled with the optical waveguide front end.

A multi-path interference filter. The multi-path interference filter includes a first port waveguide, a second port waveguide, and an optical structure connecting the first port waveguide and the second port waveguide. The optical structure has a first optical path from the first port waveguide to the second port waveguide, and a second optical path, different from the first optical path, from the first port waveguide to the second port waveguide. The first optical path has a portion, having a first length, within hydrogenated amorphous silicon. The second optical path has a portion, having a second length, within crystalline silicon, and the second optical path has either no portion within hydrogenated amorphous silicon, or a portion, having a third length, within hydrogenated amorphous silicon, the third length being less than the first length.

A VCSEL transmitter includes a first VCSEL terminal disposed on a substrate and a second VCSEL terminal adjacent thereto. The transmitter also includes a first diffraction element within a first optical path of the first VCSEL terminal which receives and changes a first direction of a first light transmission having a low-order Laguerre Gaussian mode emitted from the first VCSEL terminal. The transmitter further includes a second diffraction element within a second optical path of the second VCSEL terminal which receives the second light transmission and converts the received light into a high-order Laguerre Gaussian mode. The transmitter also includes a mode combiner to direct the first light transmission into a lens which directs the light into a multi-mode optical fiber.

A multi-path interference filter. The multi-path interference filter includes a first port waveguide, a second port waveguide, and an optical structure connecting the first port waveguide and the second port waveguide. The optical structure has a first optical path from the first port waveguide to the second port waveguide, and a second optical path, different from the first optical path, from the first port waveguide to the second port waveguide. The first optical path has a portion, having a first length, within hydrogenated amorphous silicon. The second optical path has a portion, having a second length, within crystalline silicon, and the second optical path has either no portion within hydrogenated amorphous silicon, or a portion, having a third length, within hydrogenated amorphous silicon, the third length being less than the first length.

A densely-spaced wavelength division multiplexing (DWDM) transceiver utilizes a comb laser source to provide a multi-channel system capable of supporting at least twenty separate channels. The optical transmitter portion of the transceiver utilizes a double-pass (e.g., reflective) modulator configuration. The double-pass arrangement allows for a single grating (or other suitable dispersive element) to be used as a demultiplexer in combination with the comb laser source to separate the input optical beams into individual wavelength components, as well as a multiplexer for combining the plurality of separate modulated optical signals into a single, multi-channel DWDM optical output signal. The optical receiver portion of the transceiver includes a grating element to direct the multi-channel received optical signal into separate, wavelength-based channels, with the signal propagating along each channel directed into a separate photodiode.

To provide an optical element that can be more easily aligned with an optical fiber, an optical element includes one grating coupler optically coupled to an optical fiber, a waveguide connected to the grating coupler, a multimode interferometer connected to the waveguide on the opposite side to the grating coupler, and a waveguide inserted between two input/output ports on the branched side of the multimode interferometer.

Wavelength division multiplexing devices, and methods of forming the same, include a coupling lens and a waveguide, the lens being positioned over a mirror formed in a transmission path of the waveguide. The mirror reflects incoming light signals out of the transmission path through the lens and further reflects light signals coming from the lens and into the transmission path. An optical chip is positioned near a focal length of the lens. The optical chip has an optical filter configured to transmit a light signal at a first wavelength and to reflect received light signals at wavelengths other than the first wavelength.

A variable wavelength filter includes: an input optical fiber; a diffraction grating that disperses input light from the input optical fiber; a variable mirror that has a reflective surface, wherein an angle of the reflective surface is adjustable, the variable mirror reflects the input light dispersed by the diffraction grating, the input light reflected by the variable mirror passes through a normal optical path, the input light that passes through the normal optical path has a wavelength band defined based on the angle of the reflective surface, and the defined wavelength band has a center wavelength corresponding to the angle of the reflective surface; an output optical fiber that outputs a portion of the input light that has passed through the normal optical path; and an optical detector disposed on a propagation path of the input light from the input optical fiber to the output optical fiber.