Embodiments described herein relate to a large area lens-free imaging device. One example is a lens-free device for imaging one or more objects. The lens-free device includes a light source positioned for illuminating at least one object. The lens-free device also includes a detector positioned for recording interference patterns of the illuminated at least one object. The light source includes a plurality of light emitters that are positioned and configured to create a controlled light wavefront for performing lens-free imaging.

A method for displaying virtual content to a user, the method includes determining an accommodation of the user's eyes. The method also includes delivering, through a first waveguide of a stack of waveguides, light rays having a first wavefront curvature based at least in part on the determined accommodation, wherein the first wavefront curvature corresponds to a focal distance of the determined accommodation. The method further includes delivering, through a second waveguide of the stack of waveguides, light rays having a second wavefront curvature, the second wavefront curvature associated with a predetermined margin of the focal distance of the determined accommodation.

A method includes illuminating a photonic integrated circuit (PIC) of a transmit aperture of a laser communication terminal and a PIC of a receive aperture of the laser communication terminal with multi-wavelength light, where each PIC includes multiple antenna elements forming an optical phased array (OPA). The method also includes determining light intensities of different wavelengths of the multi-wavelength light after the multi-wavelength light has passed through each PIC. The method further includes estimating phases of light associated with the antenna elements based on variations in the light intensities. In addition, the method includes adjusting one or more phase shifters of at least one of the PICs based on the estimated phases of light.

Described examples include an apparatus having a phase light modulator. The apparatus also has a first light source configured to direct a first light beam to the phase light modulator, the phase light modulator configured to provide a first modulated light beam directed to a first field of view. The apparatus also has a second light source configured to direct a second light beam to the phase light modulator, the phase light modulator configured to provide a second modulated light beam directed to a second field of view. The apparatus also has a first light detector configured to detect the first modulated light beam as reflected from the first field of view; and a second light detector configured to detect the second modulated light beam as reflected from the second field of view.

An optical beam steering device and a method for beam steering are described. The optical beam steering device including: a laser source coupled to an optical phased array (OPA) The OPA includes: a beam splitter network optically coupled to the laser source and configured to split a laser beam generated by the laser source into N outputs to generate an output optical beam; a first network of first phase shifters configured to steer the output optical beam in a first direction away from a longitude direction; and a second network of second phase shifters configured to steer the output optical beam in a second direction away from the longitude direction, the second direction being opposite to the first direction.

An active metasurface includes a number of periodically-repeated unit cells arranged on a substrate, each of the unit cells including a high-index dielectric block; a heat source positioned to selectively modulate heat applied to the high-index dielectric block; and an insulating undercut region at an interface between the high-index dielectric block and the substrate.

Methods, systems, and devices for free-space optical communications. An aircraft includes a flat optical communication terminal on an external surface of the aircraft, the flat optical communication terminal being configured to communicate with a ground station via a free-space optical communication link.

Provided is an optical phased array including a light injector, a first splitter connected to the light injector, a first phase shifter connected to the first splitter, a plurality of waveguides connected to the first splitter, portions of the plurality of waveguides being connected to the first splitter via the first phase shifter, an antenna array connected to the plurality of waveguides, a single mode filter provided in each of the plurality of waveguides, and a first photodetector connected to the first splitter and configured to detect a portion of light radiated onto the antenna array.

An optical system for detecting a scanning field, a system for controlling the optical system as well as a method for controlling the optical system, the optical system having at least one transmitter comprising at least one source for emitting electromagnetic radiation and at least one deflection unit for deflecting the beam path of the electromagnetic radiation emitted by the source into the scanning field. The optical system furthermore has at least one optical receiver comprising at least one optical filter element for filtering the electromagnetic radiation scattered back and/or reflected in the scanning field and at least one detector element for detecting the filtered electromagnetic radiation. The essence of the invention lies in the fact that it is possible to vary the wavelength of the electromagnetic radiation emitted by the source and that the variation of the wavelength occurs as a function of the deflection of the beam path.

A device for receiving light having at least one wavelength for the detection of an object, includes: an optical phased array including a plurality of optical phased sub-arrays, each optical phased sub-array including (a) a plurality of antennas and (b) a detector for coherently receiving light; and an evaluation unit connected to the optical phased sub-arrays and configured to determine the angle at which the object is detected.