An optical transmission device includes a waveguide including a transparent medium having mutually-parallel first and second surfaces arranged so that light propagates within the waveguide by internal reflection between the first and second surfaces. At least one light source is configured to inject coherent light into the waveguide. A first array of diffractive structures is applied to the waveguide and configured to couple respective beams of the coherent light out through the first surface of the waveguide. The device includes a second array of tunable optical phase modulators, which are overlaid on respective ones of the diffractive structures in the first array and are configured to apply different respective phase shifts to the respective beams, thereby modulating a far-field light pattern formed by interference between the beams.

A wavelength-tunable etalon includes a pair of substrates, each comprising a reflection layer, an electrode, and an alignment layer on opposing surfaces of the pair of substrates; a first seal line configured to seal liquid crystal between the pair of substrates; and a second seal line configured to divide a space in which the liquid crystal is sealed into a main liquid crystal accommodating space configured to pass laser and a sub-liquid crystal accommodating space provided external of the main liquid crystal accommodating space. The first seal line comprises a sub inlet configured to fluidly communicate the main liquid crystal accommodating space with the sub-liquid crystal accommodating space.

A tunable liquid crystal (LC) device includes an LC layer between a pair of reflectors forming an optical cavity. The reflectors include conductive layers for applying an electrical signal to the LC layer. One of the conductive layers may include an array of conductive pixels for spatially selective control of the effective refractive index of the LC layer. The phase delay introduced by the LC layer may be greatly increased or magnified by placing the LC layer into the optical cavity. This enables a substantial reduction of the LC layer thickness, which in its turn enables very tight pitches of the LC pixels, with a reduced inter-pixel crosstalk caused by fringing electric fields, as well as faster switching times. A tight-pitch, fast LC device may be used as a configurable hologram or a spatial light modulator.

A tunable liquid crystal (LC) device includes an LC layer between a pair of reflectors forming an optical cavity. The reflectors include conductive layers for applying an electrical signal to the LC layer. One of the conductive layers may include an array of conductive pixels for spatially selective control of the effective refractive index of the LC layer. The phase delay introduced by the LC layer may be greatly increased or magnified by placing the LC layer into the optical cavity. This enables a substantial reduction of the LC layer thickness, which in its turn enables very tight pitches of the LC pixels, with a reduced inter-pixel crosstalk caused by fringing electric fields, as well as faster switching times. A tight-pitch, fast LC device may be used as a configurable hologram or a spatial light modulator.

The disclosure provides a method for fabricating a metallic optical metasurface having an array of hologram elements. The method includes forming a first copper layer protected with a conducting or dielectric barrier layer over a backplane structure by a damascene process. The first copper layer comprises a plurality of nano-gaps vertically extending from the backplane structure. The plurality of nano-gaps is filled with a dielectric material. The method also includes removing the dielectric material and a portion of the conducting or dielectric barrier layer to expose the portions in the nano-gaps of the first copper layer. The method may further include depositing a dielectric coating layer over the top portion and exposed side portions of the first copper layer to form a protected first copper layer, and filling the gaps with an electrically-tunable dielectric material that has an electrically-tunable refractive index.

A camera includes one or more spectral illuminators, a tunable optical filter optically intermediate the one or more spectral illuminators and a scene, and a sensor array. The one or more spectral illuminators are configured to emit active spectral light. The tunable optical filter is dynamically adjustable to change a selected sub-band of the active spectral light that illuminates the scene. The sensor array includes a plurality of sensors each configured to measure spectral light reflected from the scene in the selected sub-band.

An optical receiver for use in free space communication from a transmitter to the optical receiver is configured for receiving optical signals from the transmitter. The optical receiver includes optics for collecting the optical signals, a demodulator for converting the optical signals so collected into a data stream, a signal processing unit for processing the data stream into an analog signal, and an analog-to-digital converter for converting the analog signal into a digital output. The demodulator includes a plurality of apertures and at least one Fabry-Perot etalon, through which at least a portion of the optical signals is transmitted. The demodulator also includes at least one phase detection region for detecting at least the portion of the optical signals transmitted through the at least one Fabry-Perot etalon to form a phase signal.

Provided is a tunable electro-optic filter including a reflective structure including a first reflective layer including a first pattern layer having a first meta-surface structure disposed on a first side of the liquid crystal layer and a second reflective layer including a second pattern layer having a second meta-surface structure disposed on a second side of the liquid crystal layer. Each of the first meta-surface structure and the second meta-surface structure includes multiple dielectric materials which are alternately stacked, and a thickness of each dielectric material gradually increases. Alternately, the tunable electro-optic filter may include a pattern layer having a meta-surface structure disposed on at least a side of the liquid crystal layer.

A camera includes one or more spectral illuminators, a tunable optical filter optically intermediate the one or more spectral illuminators and a scene, and a sensor array. The one or more spectral illuminators are configured to emit active spectral light. The tunable optical filter is dynamically adjustable to change a selected sub-band of the active spectral light that illuminates the scene. The sensor array includes a plurality of sensors each configured to measure spectral light reflected from the scene in the selected sub-band.

An electro-optical beamsteerer can be coupled with other optical structures. For example, such optical structures can be used to shape a beam being steered by the beamsteerer or shape a field-of-regard (FOR) addressable from the perspective of the beamsteerer. Optical elements placed at an output of the LCW can be used as a spot mapper to increase or decrease the field of view that can be scanned by a beam steered by the LCW, as an illustrative example, Lenses or other optical elements can also be used to correct distortion in the steered beam distribution across the field of view, such as to provide a smile corrector. In a similar manner, optical elements can be placed at an input to the beamsteerer, such as to provide a beam expander to change the size of the beam profile inside the beamsteerer device.