An apparatus comprises: a photonic integrated circuit comprising an optical phased array, a first focusing element at a fixed position relative to the optical phased array and configured to couple an optical beam to or from the optical phased array, and a second focusing element at a fixed position relative to the first focusing element and configured to couple the optical beam to or from the first focusing element. At least one of the first or second focusing element is externally coupled to the photonic integrated circuit, and the first and second focusing elements have different effective focal lengths.

A device for optical signal processing includes a first layer, a second layer and a waveguiding layer. A lens is disposed within the first layer and adjacent to a surface of the first layer. The second layer is underneath the first layer and adjacent to another surface of the first layer. The waveguiding layer is located underneath the second layer and configured to waveguide a light beam transmitted in the waveguiding layer. A grating coupler is disposed over the waveguiding layer. The lens is configured to receive, from one of the grating coupler or a light-guiding element, the light beam, and focus the light beam towards another one of the light-guiding element or the grating coupler.

A device for optical signal processing includes a first layer, a second layer and a waveguiding layer. A lens is disposed within the first layer and adjacent to a surface of the first layer. The second layer is underneath the first layer and adjacent to another surface of the first layer. The waveguiding layer is located underneath the second layer and configured to waveguide a light beam transmitted in the waveguiding layer. A grating coupler is disposed over the waveguiding layer. The lens is configured to receive, from one of the grating coupler or a light-guiding element, the light beam, and focus the light beam towards another one of the light-guiding element or the grating coupler.

The present application discloses an optical structure. The optical structure includes a waveguide, and a first coupling-out grating, a second coupling-out grating, and a third coupling-out grating provided on the waveguide. The third coupling-out grating is located between the first coupling-out grating and the second coupling-out grating; the first coupling-out grating is a two-dimensional grating having a plurality of first grids, and the first grid is in an asymmetric shape, such that light efficiency of the first coupling-out grating propagating along a first direction is higher than light efficiency of the first coupling-out grating propagating along a second direction.

The present application discloses an optical structure. The optical structure includes a waveguide, and a first coupling-out grating, a second coupling-out grating, and a third coupling-out grating provided on the waveguide. The third coupling-out grating is located between the first coupling-out grating and the second coupling-out grating; the first coupling-out grating is a two-dimensional grating having a plurality of first grids, and the first grid is in an asymmetric shape, such that light efficiency of the first coupling-out grating propagating along a first direction is higher than light efficiency of the first coupling-out grating propagating along a second direction.

Apparatuses, systems and methods for optical coupling, optical integration, electro-optical coupling, and electro-optical packaging are described herein. Optical couplers may comprise various optical elements (e.g., mirrors as described herein) to relax optical assembly requirements and improve producibility. Optical couplers may improve fiber-to-chip, fiber-to-fiber and chip-to-chip optical connection. Optical couplers and optical components may be used to improve integration of, connection of, and/or packaging of optical systems and/or components with electrical systems and/or components.

Apparatuses, systems and methods for optical coupling, optical integration, electro-optical coupling, and electro-optical packaging are described herein. Optical couplers may comprise various optical elements (e.g., mirrors as described herein) to relax optical assembly requirements and improve producibility. Optical couplers may improve fiber-to-chip, fiber-to-fiber and chip-to-chip optical connection. Optical couplers and optical components may be used to improve integration of, connection of, and/or packaging of optical systems and/or components with electrical systems and/or components.

A graded-index optical element may include a nanovoided material including a first surface and a second surface opposite the first surface. The nanovoided material may be transparent between the first surface and the second surface. Additionally, the nanovoided material may have a predefined change in effective refractive index in at least one axis due to a change in at least one of nanovoid size or nanovoid distribution along the at least one axis. Various other elements, devices, systems, materials, and methods are also disclosed.

An optical device includes a first waveguide extending in a first direction and a second waveguide connected to the first waveguide. The second waveguide includes a first mirror, a second mirror, and an optical waveguide layer. At least either the first waveguide or the second waveguide has one or more gratings in a part of a connection region in which the first mirror, the second mirror, and the first waveguide overlap one another when seen from an angle parallel with a direction perpendicular to a first reflecting surface of the first mirror. The one or more gratings is at a distance that is longer than at least either a thickness of the first mirror or a thickness of the second mirror in the first direction from an end of the first mirror or the second mirror that is in the connection region.

An optical device includes a first waveguide extending in a first direction and a second waveguide connected to the first waveguide. The second waveguide includes a first mirror, a second mirror, and an optical waveguide layer. At least either the first waveguide or the second waveguide has one or more gratings in a part of a connection region in which the first mirror, the second mirror, and the first waveguide overlap one another when seen from an angle parallel with a direction perpendicular to a first reflecting surface of the first mirror. The one or more gratings is at a distance that is longer than at least either a thickness of the first mirror or a thickness of the second mirror in the first direction from an end of the first mirror or the second mirror that is in the connection region.