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.

The present invention relates to a new method for making metasurfaces comprising liquid gating.

An optical sensor system, comprising refractory plasmonic elements that can withstand temperatures exceeding 2500° C. in chemically aggressive and harsh environments that impose stress, strain and vibrations. A plasmonic metamaterial or metasurface, engineered to have a specific spectral and angular response, exhibits optical reflection characteristics that are altered by varying physical environmental conditions including but not limited to temperature, surface chemistry or elastic stress, strain and other types of mechanical load. The metamaterial or metasurface comprises a set of ultra-thin structured layers with a total thickness of less than tens of microns that can be deployed onto surfaces of devices operating in harsh environmental conditions. The top interface of the metamaterial or metasurface is illuminated with a light source, either through free space or via an optical fiber, and the reflected signal is detected employing remote detectors.

The present invention aims to provide a low refractive index layer that can attain both a low refractive index and a high mechanical strength even when it has a large thickness. The low refractive index layer of the present invention is a low refractive index layer in the form of a void-containing layer, wherein hollow particles each having a void space inside are further contained in the void-containing layer, and the low refractive index layer has a refractive index of 1.25 or less.

An active metamaterial array of the present disclosure includes: a substrate; a plurality of metamaterial structures disposed on the substrate and spaced apart from each other; a conductivity variable material layer formed between each of the plurality of the metamaterial structures so as to selectively connect the metamaterial structures; an electrolyte material layer formed on the metamaterial structures and the conductivity variable material layer; and a gate electrode disposed at one end of the substrate so as to be in contact with one region of the electrolyte material layer, and when an external voltage is applied to the gate electrode, the gate electrode changes the conductivity of the conductivity variable material layer by controlling the migration of ions contained in the electrolyte material layer.

A photonic crystal, a light conversion device, a display panel, and a pair of glasses are provided. The photonic crystal of the embodiment of the present disclosure includes first dielectric layers and second dielectric layers having different refractive indexes, and the first dielectric layers and the second dielectric layers are alternately stacked. A thickness and a refractive index of each of the first dielectric layers and a thickness and a refractive index of each of the second dielectric layers are configured such that the photonic crystal blocks blue light with a wavelength of 420 nm to 470 nm incident into the photonic crystal from passing through the photonic crystal.

A robust conjugate symmetric optical apparatus is disclosed. The robust conjugate symmetric optical apparatus comprises a first optical cell set and a second optical cell set. The first optical cell set includes a first plurality of cells, each of which includes a first left half cell and a first right half cell, and the respective first right half cell and the corresponding first left half cells form a first symmetric structure therebetween. The second optical cell set includes a second plurality of cells, each of which includes a second left half cell and a second right half cell, and the respective second right half cell and the corresponding second left half cells form a second symmetric structure therebetween, wherein each of the first left half cells of the first optical cell set and each of the second right half cells of the second optical cell set have the same structure; and each of the first right half cells of the first optical cell set and each of the second left half cells of the second optical cell set have the same structure.

Disclosed is a diffractive optical element includes a substrate (BS) having a first surface and a second surface opposite the first surface, being transparent to light in at least one spectral range and having, in the spectral range, a refractive index that is greater than that of water, at least one metasurface able to diffract light radiation of wavelength λ within the spectral range, incident with an angle of incidence, according to a diffracted radiation, so that the diffracted radiation propagates in the substrate and reaches the second surface of the substrate at a diffracted angle θ.sub.d that is greater than or equal to a limit angle (θ.sub.c) of total internal reflection between the substrate and water, the metasurface being designed to have, for the angle of incidence, a transmission with a 0 order of diffraction below 5% and a transmission of the diffracted radiation corresponding to a −1 or +1 order of diffraction above 50%.

A head-mounted display device wearable by a user and supporting a mixed-reality experience includes a see-through display system through which the user can view a physical world and on which virtual images are renderable. At least one light source is configured to emit near infrared (IR) light that illuminates an eye of the user of the near-eye mixed reality display device. An imaging sensor is configured to capture reflections of the near IR light reflected from the eye of the user. A metalens is configured to receive the reflections of the IR light reflected from the eye of the user and direct the reflections onto the image sensor.

Provided are a method of preparing quantum dots, a quantum dot prepared by the method, an optical member including the quantum dot, and an electronic apparatus including the quantum dot. The method includes: preparing a mixture of a semiconductor compound including indium (In), a first precursor including a first metal element, a second precursor including a second metal element, a third precursor including a third element, and a fourth precursor including a fourth element; and heating the mixture, wherein the first precursor and the second precursor are different from each other, and the third precursor and the fourth precursor are different from each other.