An optical waveguide comprises one or more upstream diffraction gratings in addition to overlapping first and second downstream diffraction gratings. The one or more upstream diffraction gratings include a first upstream diffraction grating configured to receive display light and to release the display light expanded along a first axis. The first and second downstream diffraction gratings are configured to receive the display light expanded along the first axis and to cooperatively release the display light further expanded along a second axis. The first downstream diffraction grating is arranged on a planar face of the optical waveguide and is further configured to further expand along the first axis the display light expanded along the first axis.

An eyepiece includes a substrate and an in-coupling grating patterned on a single side of the substrate. A first grating coupler is patterned on the single side of the substrate and has a first grating pattern. The first grating coupler is optically coupled to the in-coupling grating. A second grating coupler is patterned on the single side of the substrate adjacent to the first grating coupler. The second grating coupler has a second grating pattern different from the first grating pattern. The second grating coupler is optically coupled to the in-coupling grating.

An eyepiece includes a substrate and an in-coupling grating patterned on a single side of the substrate. A first grating coupler is patterned on the single side of the substrate and has a first grating pattern. The first grating coupler is optically coupled to the in-coupling grating. A second grating coupler is patterned on the single side of the substrate adjacent to the first grating coupler. The second grating coupler has a second grating pattern different from the first grating pattern. The second grating coupler is optically coupled to the in-coupling grating.

Structures for a filter and methods of fabricating a structure for a filter. The filter is coupled to a waveguide core. The filter includes a first plurality of grating structures positioned adjacent to a first section of the waveguide core and a second plurality of grating structures positioned adjacent to a second section of the waveguide core. The first plurality of grating structures are configured to cause laser light in a first portion of a wavelength band to be transferred between the first section of the waveguide core and the first plurality of grating structures. The second plurality of grating structures are configured to cause laser light in a second portion of a wavelength band to be transferred between the second section of the waveguide core and the second plurality of grating structures.

An eyepiece includes a substrate and an in-coupling grating patterned on a single side of the substrate. A first grating coupler is patterned on the single side of the substrate and has a first grating pattern. The first grating coupler is optically coupled to the in-coupling grating. A second grating coupler is patterned on the single side of the substrate adjacent to the first grating coupler. The second grating coupler has a second grating pattern different from the first grating pattern. The second grating coupler is optically coupled to the in-coupling grating.

An optical waveguide comprises one or more upstream diffraction gratings in addition to overlapping first and second downstream diffraction gratings. The one or more upstream diffraction gratings include a first upstream diffraction grating configured to receive display light and to release the display light expanded along a first axis. The first and second downstream diffraction gratings are configured to receive the display light expanded along the first axis and to cooperatively release the display light further expanded along a second axis. The first downstream diffraction grating is arranged on a planar face of the optical waveguide and is further configured to further expand along the first axis the display light expanded along the first axis.

An optical waveguide that performs both in-coupling and out-coupling using two diffractive optical elements is provided. Each optical element is a diffraction grating and can be applied to the same or different surface of the optical waveguide. The diffraction gratings overlap to form two overlapping regions. The first overlapping region in-couples light into the waveguide and the second overlapping region out-couples light from the optical waveguide. Because the optical waveguide only uses two gratings, and therefore only has two grating vectors, the optical waveguide is easier to manufacture than optical waveguides with a greater number of grating vectors.

Structures that include an optical component, such as a grating coupler, and methods of fabricating a structure that includes an optical component, such as a grating coupler. First and second layers are arranged over the optical component with the first layer arranged between the second layer and the optical component. The first and second layers are each composed of a tunable material having a refractive index that is a function of a bias voltage applied to the first layer and the second layer.

An optical measurement apparatus configured to measure a photonic integrated circuit (photonic IC) is provided. The optical measurement apparatus includes a substrate, at least one optical waveguide device, a first connector, and a second connector. The at least one optical waveguide device is disposed on the substrate. The first connector and the second connector are connected with the at least one optical waveguide device. An optical signal from a first optical fiber is transmitted to the at least one optical waveguide device through the first connector, transmitted to the inside of the photonic IC though at least one first evanescent coupler of the photonic IC, transmitted to the at least one optical waveguide device through at least one second evanescent coupler of the photonic IC, and transmitted to a second optical fiber through the second connector in sequence.

An optical measurement apparatus configured to measure a photonic integrated circuit (photonic IC) is provided. The optical measurement apparatus includes a substrate, at least one optical waveguide device, a first connector, and a second connector. The at least one optical waveguide device is disposed on the substrate. The first connector and the second connector are connected with the at least one optical waveguide device. An optical signal from a first optical fiber is transmitted to the at least one optical waveguide device through the first connector, transmitted to the inside of the photonic IC though at least one first evanescent coupler of the photonic IC, transmitted to the at least one optical waveguide device through at least one second evanescent coupler of the photonic IC, and transmitted to a second optical fiber through the second connector in sequence.