Provided is a beam steering apparatus including a driving pixel unit including a plurality of driving pixels that are respectively configured to supply a voltage or a current, a light modulator including a plurality of pixels corresponding to the plurality of driving pixels, each pixel of the plurality of pixels being configured to modulate incident light, and a wiring layer including a wiring structure configured to electrically connect the plurality of driving pixels to the plurality of pixels, wherein the wiring structure includes a first conductive wire connected to the plurality of driving pixels, a second conductive wire connected to the plurality of pixels, and at least one third conductive wire connected between the first conductive wire and the second conductive wire, and wherein the first conductive wire, the second conductive wire, and the at least one third conductive wire form a step structure.

A security device includes a diffractive structure, including grating elements and having a first area, the grating elements within a region have a constant pitch or spacing; the first area regions pitches or spacings increase from one region to the next between a first region having a grating element pitch or spacing of less than or equal to 0.6 microns and an end region having a grating element pitch or spacing of greater than or equal to 5 microns; upon illumination and viewing along a first viewing direction substantially orthogonal to the first axis, the device exhibits a first optical effect in that at least one region exhibits a diffractive colour; each region has at least first and second sub-regions having different grating element orientations within the plane of the device such that the first optical effect is exhibited at more than one angle of tilt about the second axis.

There is provided a transparent screen which is capable of separating a direction where a hot spot is observed and a direction where a bright video is allowed to be observed, and establishing a direction where a video is allowed to be wholly brightly observed. A transparent screen includes a first transparent layer, a reflective layer reflecting projected video light, a second transparent layer disposed opposite to the first transparent layer with respect to the reflective layer so as to make a background visible therethrough; wherein the reflective layer has a plurality of slant reflective surfaces, each of the slant reflective surfaces being slant to a reference surface that is a surface of the first transparent layer opposite to the reflective layer; wherein each of the slant reflective surfaces is provided with a concavo-convex and is formed in a stripe shape when seen from a normal direction of the reference surface; and wherein the slant reflective surfaces are disposed so as to have angles to the reference surface, the angle changing with random variations in of range with respect to a certain central angle.

A laser interferometer that includes a light source configured to emit laser light, an optical divider configured to divide the laser light into a first optical path and a second optical path, an optical modulator being provided on the first optical path or the second optical path, including an oscillator that oscillates when a current is applied, and being configured to modulate the laser light by using the oscillator, a photoreceptor configured to receive the laser light and output a photoreception signal, the laser light being reflected by an object to be measured that is provided on the first optical path or the second optical path, and a demodulation circuit configured to demodulate, from the photoreception signal, a Doppler signal derived from the object to be measured, based on a reference signal and a modulation signal derived from the optical modulator, wherein Iq/f≤1×10.sup.−7 is satisfied, where an amplitude value of the current applied to the oscillator that is oscillating is Iq [A] and an oscillation frequency of the oscillator is f [Hz].

A laser interferometer that includes a laser light source configured to emit emission light, a light splitter configured to split the emission light into first split light, and second split light incident on an object to be measured, a light modulator disposed on an optical path on which the first split light advances, and configured to modulate the first split light into a reference light having a different frequency from a frequency of the first split light, an optical path length change unit provided between the light splitter and the light modulator, and configured to change a first optical path length, the first optical path length being an optical path length between the light splitter and the light modulator, a photoreceptor configured to receive an interference light of the reference light and an object light generated by reflecting the emission light at the object to be measured, and to output a light reception signal, and a controller configured to control operation of the optical path length change unit in accordance with a second optical path length, the second optical path length being an optical path length between the light splitter and the object to be measured.

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%.

An optical identifier including a recording surface, a plurality of deflection cells each of which has recorded thereon a range in which light to be diffracted is deflected, at least one spatial phase modulator which fills a space between the deflection cells on the recording surface, and a deposition layer which covers part or all of the recording surface. The deflection cells has a spatial frequency expressed in a form of a relief structure and are discretely formed on the recording surface at regular intervals away from each other. A variable color image is recorded by pixels defined by the deflection cells. The spatial phase modulator has thereon a distribution of phase differences recorded in a form of heights of the relief structure. The spatial phase modulator modulates a phase of light outputted from a point light source and displays a reproduced image.

A diffractive optical member includes a hologram element, a support member that supports the hologram element by contacting the hologram element from one side, and a covering film member that is a first film member and covers the hologram element by contacting the hologram element from a side opposite to the one side. The covering film member includes a coupling portion that is in contact with the support member, and the coupling portion is separated from the hologram element.

A subwavelength grating displaying a colored image exhibiting a color corresponding to a grating period of a subwavelength grating in reflection directions including a specular reflection direction. A relief surface displaying a reflection image in monochromatic reflected light in reflection directions including a direction different from the specular reflection direction. An optical element has a first state in which neither a colored image nor a reflection image is displayed, a second state in which the colored image is mainly displayed, and a third state in which the reflection image is mainly displayed. A plane in which the optical element is disposed and a plane including a line of sight of an observer form an observation angle therebetween. The optical element is observed in any of the first, second and third states according to the observation angle.

An internal laser component of an optical device comprises: a waveguide that defines a guided mode of a first optical wave characterized by a first propagation constant associated with a first effective refractive index. An optical antenna grating comprises: a waveguide that defines a guided mode of a second optical wave characterized by a second propagation constant associated with a second effective refractive index, and a grating structure configured to emit a portion of the second optical wave in a selected direction. The internal laser component and the optical antenna grating are configured to provide a relationship between the first effective refractive index and the second effective refractive index such that the selected direction is substantially insensitive to a change in a temperature of a thermal environment in which the internal laser component and the optical antenna grating are thermally coupled.