An optical element includes a nanovoided polymer layer having a first refractive index in an unactuated state and a second refractive index different than the first refractive index in an actuated state. Compression or expansion of the nanovoided polymer layer, for instance, can be used to reversibly control the size and shape of the nanovoids within the polymer layer and hence tune its refractive index over a range of values, e.g., during operation of the optical element. Various other apparatuses, systems, materials, and methods are also disclosed.

Examples include a device including a nanovoided polymer element having a first surface and a second surface, a first plurality of electrodes disposed on the first surface, a second plurality of electrodes disposed on the second surface, and a control circuit configured to apply an electrical potential between one or more of the first plurality of electrodes and one or more of the second plurality of electrodes to induce a physical deformation of the nanovoided polymer element.

An example device includes a nanovoided polymer element, which may be located at least in part between the electrodes. In some examples, the nanovoided polymer element may include anisotropic voids, including a gas, and separated from each other by polymer walls. The device may be an electroactive device, such as an actuator having a response time for a transition between actuation states. The gas may have a characteristic diffusion time (e.g., to diffuse half the mean wall thickness through the polymer walls) that is less than the response time. The nanovoids may be sufficiently small (e.g., below 1 micron in diameter or an analogous dimension), and/or the polymer walls may be sufficiently thin, such that the gas interchange between gas in the voids and gas absorbed by the polymer walls may occur faster than the response time, and in some examples, effectively instantaneously.

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.

An optical device fabrication method includes removing semiconductor material from a semiconductor substrate to form a first curved surface and a second curved surface, forming a bonding material on the first curved surface, and selectively removing semiconductor material from at least one of the first and the second curved surfaces to form one or more subwavelength structures. The semiconductor substrate has a bandgap wavelength associated with a bandgap energy of the semiconductor material. The optical device refracts certain incident electromagnetic radiation and/or filters other electromagnetic radiation. The refracted radiation includes infrared wavelengths longer than the bandgap wavelength and the filtered radiation includes wavelengths shorter than the bandgap wavelength.

An optical device fabrication method includes removing semiconductor material from a semiconductor substrate to form a first curved surface and a second curved surface, forming a bonding material on the first curved surface, and selectively removing semiconductor material from at least one of the first and the second curved surfaces to form one or more subwavelength structures. The semiconductor substrate has a bandgap wavelength associated with a bandgap energy of the semiconductor material. The optical device refracts certain incident electromagnetic radiation and/or filters other electromagnetic radiation. The refracted radiation includes infrared wavelengths longer than the bandgap wavelength and the filtered radiation includes wavelengths shorter than the bandgap wavelength.

A method is provided. The method comprises: injecting an optical carrier signal into an unbent optical waveguide between two reflectors, where the distance between two reflectors in the center of the two reflectors is substantially zero and the two reflectors undergo substantially a phase shift where the two reflectors are adjacent; creating standing waves between the two reflectors in the center, and a single resonance due to constructive interference; applying a varying electric field across the unbent optical waveguide centered between two reflectors and extending a length less than or equal to a combined length of the two reflectors; and generating a modulated carrier signal at at least one of an input and an output of the unbent optical waveguide between the two reflectors.

A method is provided. The method comprises: injecting an optical carrier signal into an unbent optical waveguide between two reflectors, where the distance between two reflectors in the center of the two reflectors is substantially zero and the two reflectors undergo substantially a phase shift where the two reflectors are adjacent; creating standing waves between the two reflectors in the center, and a single resonance due to constructive interference; applying a varying electric field across the unbent optical waveguide centered between two reflectors and extending a length less than or equal to a combined length of the two reflectors; and generating a modulated carrier signal at at least one of an input and an output of the unbent optical waveguide between the two reflectors.

A photonic integrated circuit comprises an input interface adapted for receiving an optical input signal and splitting it into two distinct polarization modes and furthermore adapted for rotating the polarization of one of the modes for providing the splitted signals in a common polarization mode. The PIC also comprises a combiner adapted for combining the first mode signal and the second mode signal into a combined signal and a decohering means adapted for transforming at least one of the first mode signal and the second mode signal such that the first mode signal and the second mode signal are received by the combiner in a mutually incoherent state. A processing component for receiving and processing said combined signal is also comprised.

A photonic integrated circuit comprises an input interface adapted for receiving an optical input signal and splitting it into two distinct polarization modes and furthermore adapted for rotating the polarization of one of the modes for providing the splitted signals in a common polarization mode. The PIC also comprises a combiner adapted for combining the first mode signal and the second mode signal into a combined signal and a decohering means adapted for transforming at least one of the first mode signal and the second mode signal such that the first mode signal and the second mode signal are received by the combiner in a mutually incoherent state. A processing component for receiving and processing said combined signal is also comprised.