Abstract: A lens system provides to a user, a high-definition image in which generation of concentric circles is reduced. The lens system has one or more Fresnel lenses. A lens surface of each of the Fresnel lenses has a plurality of grooves that is concentrically formed. Both a pitch which is the distance between two adjacent grooves and the depth of each of the plurality of grooves vary with the distance from an optical axis that passes through the center of the lens system.

Abstract: A lens system includes a plurality of lens elements arranged from an object side to an image plane side, and a diaphragm arranged between the plurality of lens elements. The plurality of lens elements include a plurality of freeform lenses each having a freeform surface that is asymmetrical with respect to a first direction and a second direction which cross with each other. At least one freeform lens is placed on the image plane side of the diaphragm. With a lens thickness T1 in the first direction at a maximum height of an axial ray and a lens thickness T2 in the second direction at the maximum height of the axial ray, at least one freeform lens satisfying 0.3<T1/T2<0.76 is placed on the object side of the diaphragm.

Abstract: A virtual image display apparatus includes an image light emitting unit configured to emit image light, and a see-through mirror which is an optical member having a reflective film that reflects the image light, wherein the see-through mirror includes a first region on which a light ray of the image light corresponding to a center angle of view is incident and a second region on which a light ray of the image light which different from the light ray corresponding to the center angle of view is incident, a film thickness in the first region of the reflective film is thicker than a film thickness in the second region, and the first region of the reflective film has reflectivity characteristics corresponding to a wavelength band which is wider toward the long wavelength side than a wavelength band of the image light emitted from the image light emitting unit.

Abstract: Provided is a control device for controlling a Fabry-Perot interference filter having a pair of mirror parts and a pair of driving electrodes. The control device includes: a first driving source that is controlled by using a current as a control parameter, and changes the distance between the pair of mirror parts; a second driving source that is controlled by using a voltage as a control parameter, and changes the distance; and a control unit that controls the first driving source and the second driving source in such a way that the distance is changed by a first driving source in a first region and the distance is changed by the second driving source in at least one part of an region other than the first region when an region including a maximum of the voltage is defined as the first region.

Abstract: The present disclosure relates to an ophthalmic lens with an extended depth of field including an optical unit that includes a first surface and a second surface both centered by an optical axis and opposite to each other. At least one of the first and second surfaces is defined by a superposition of a base sag profile and a feature sag profile and includes in sequence a first zone, a second zone, and a third zone along a radial direction away from the optical axis. The first zone is designed as a freeform surface zone, and the second zone is designed as a phase transition zone. The ophthalmic lens enables patients to acquire a continuous range of vision from intermediate to far distances and also optimizes their far vision without visual interference, such that the resulting far vision correction is equivalent to that of existing monofocal ophthalmic lenses.

Abstract: The invention relates to a diffractive optical element with a spatial variation in the refractive index, wherein a sequence of adjacent sections, which form a diffractive structure, is formed by the spatial variation in the refractive index, within which sections the refractive index varies in each case. Over a spectral range extending over at least 300 nm, the diffractive structure has a diffraction efficiency of at least 0.95, averaged over the entire spectral range. The value of the diffraction efficiency of at least 0.95, averaged over the entire spectral range, is realized by a single single-layer diffractive structure with an optimized combination of at least two refractive indices and at least two Abbe numbers within each section of the sequence of adjacent sections. The refractive index variation can be achieved by means of doping, material mixing, or structuring into sub-wavelength ranges.

Abstract: A small integrated free space circulator, comprising a first polarizing beam splitter (1), a half-wave plate (2), a Faraday rotating plate (3), a beam splitter (4), a quarter-wave plate (5), and a pair of reflective plates (6, 7), wherein the first polarizing beam splitter (1), the half-wave plate (2), the Faraday rotating plate (3), and the beam splitter (4) are sequentially arranged, the quarter-wave plate (5) and the reflective plate (6) are sequentially attached to a side surface of the first polarizing beam splitter (1) adjacent to the half-wave plate (2), and the reflective plate (7) is arranged on a side surface of the beam splitter (4, 8) adjacent to or opposite to the Faraday rotating plate (3); when the reflective plate (7) is arranged on the side surface of the beam splitter (8) opposite to the Faraday rotating plate (3), the reflective plate (7) partially covers the side surface of the beam splitter (8) opposite to the Faraday rotating plate (3).

Abstract: Polarization-insensitive metasurfaces using anisotropic nanostructures are disclosed. These anisotropic structures allow for an accurate implementation of phase, group delay, and group delay dispersion, while simultaneously making it possible to realize a polarizationinsensitive, diffraction-limited and achromatic metalens for wavelength, e.g., ?=from about 460 nm to about 700 nm. The approach of polarization-insensitivity can be also applied for other metasurface devices with applications in, e.g., imaging and virtual or augmented reality.

Abstract: A deformable mirror device has a flexible layer with a front surface that forms a mirror surface or to which a mirror layer forming mirror surface is attached. The flexible layer consists homogeneously of a first material. Protrusions extend from the back surface of the flexible layer. The protrusions consist homogeneously of the first material or a material with substantially the same thermal expansion coefficient. A plurality actuators are coupled to the protrusions and via the protrusions to the flexible layer, to deform the flexible layer. The flexible layer and the protrusions may be part of an integral body of the first material, or bonded to the flexible layer. The distal end of each protrusion has a curved surface that at least partly has a spherical shape.

Abstract: A light diffraction element, that has cells, includes first regions and second regions. Each of the cells comprises one of the first regions and one of the second regions. Each of the first regions has a thickness or a refractive index that is independently set. The second regions have a uniform thickness or a uniform refractive index. The first regions allow first polarized components of signal light to pass through. The second regions allow second polarized components of signal light to pass through. The second polarized components are different, in polarization direction, from the first polarized components. The light diffraction element performs optical computing by causing the first polarized components of signal light that have passed through the first regions to interfere with each other. The first polarized components of signal light output from the light diffraction element indicate information after the optical computing.

Abstract: An adapter includes a hollow adapter body, a rotating ring connected to a second side of the adapter body, and at least three sliding connecting pieces. The rotating ring includes at least two rotating ring guide grooves corresponding to each sliding connecting piece. The adapter body includes at least two adapter body guide grooves corresponding to each sliding connecting piece. Each sliding connecting piece includes a connecting portion. When each sliding connecting piece moves along the corresponding at least two rotating ring guide grooves and the corresponding at least two adapter body guide grooves, configuration of the rotating ring guide grooves and the adapter body guide grooves make connecting portions move away from or close to the rotating ring in a direction perpendicular to the axial direction of the rotating ring and form a circumferential distribution, so as to match and connect with camera lenses having different apertures.

Abstract: The present disclosure discloses an optical imaging system. The optical imaging system comprises, sequentially along an optical axis from an object side to an image side, a stop; a first lens, having a positive refractive power; a second lens, having a refractive power; a third lens, having a refractive power; a fourth lens, having a negative refractive power, an object-side surface of the fourth lens is a convex surface; a fifth lens, having a negative refractive power; a sixth lens, having a refractive power; and a seventh lens, having a refractive power. Here, one of the first to seventh lenses is an aspheric lens made of glass, and a radius of curvature R2 of an image-side surface of the first lens and a radius of curvature R1 of an object-side surface of the first lens satisfy: 2.5?(R2+R1)/R2?R1)<3.0.

Abstract: An optical imaging device for a microscope includes an objective and an optical system configured to interact with the objective for optically imaging an object selectively in a first operating mode and a second operating mode. The optical system includes a first optical subsystem associated with the first operating mode, and a second optical subsystem associated with the second operating mode. The first optical subsystem is configured to form a first image of the object with a first magnification. The second optical subsystem is configured to form a second image of the object with a second magnification that is less than the first magnification. The second optical subsystem includes an optical module insertable into the optical path for selecting the second operating mode. The optical module includes a lens element with a positive refractive power.

Abstract: An optical device and an eyeware apparatus comprising the optical device are disclosed. The optical device comprises a diffraction grating configured to diffract an incident light of a given wavelength on said optical device, said diffraction grating having a grating pitch above said given wavelength and being configured to diffract said incident light at a diffraction order having an absolute value equal to or greater than 2, wherein the optical device comprises an optical waveguide configured for guiding said light diffracted at a diffraction order having an absolute value equal to or greater than 2. The diffraction grating comprises a substrate of a first dielectric material with refractive index n3 and at least one second dielectric material with refractive index n2 deposited on said substrate, where n3<n2 or n3=n2.

Abstract: An optical element driving mechanism is provided, including a movable part, a fixed part, and a driving assembly. The movable part is for connecting the optical element. The movable part is movable relative to the fixed part. The driving assembly is used for generating a driving force to drive the movable part to move relative to the fixed part. The driving assembly further includes a first reinforcement element, for strengthening the driving force.

Abstract: There is provided a light diffusion film in which a decrease in the half-value angle can be suppressed even after processing with a high elongation rate. A light diffusion film including a base material film and a light diffusing layer, the light diffusing layer containing light diffusing particles and a resin binder, wherein a ratio (T/t) of an average film thickness T of the light diffusing layer, to an average particle diameter t of the light diffusing particles, is 3.0 or more.

Abstract: The light-guide plate includes a substrate, an incidence diffraction grating that diffracts incident light, and an emission diffraction grating that emits light from the substrate, the light being diffracted by the incidence diffraction grating. The emission diffraction grating is formed of a recessed/projected pattern formed on a substrate surface, the recessed/projected pattern includes a first group of parallel straight lines and a second group of parallel straight lines intersecting the first group of parallel straight lines, and a pitch of the first group of parallel straight lines is equal to a pitch of the second group of parallel straight lines. A relationship between the pitch P of the first group of parallel straight lines and the second group of parallel straight lines and a pattern width W of the recessed/projected pattern is defined as W/P, which is 0.15 or more and 0.85 or less.

Abstract: An optical member driving mechanism is provided, including a first movable portion, a fixed portion, and a first driving assembly. The first movable portion is connected to an optical member. The first movable portion is movable relative to the fixed portion. The first driving assembly is configured to drive the first movable portion to move relative to the fixed portion.

Abstract: A photographing optical lens system includes five lens elements being, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. Each lens element has an object-side surface facing the object side and an image-side surface facing the image side. The first lens element has positive refractive power and the object-side surface being convex in a paraxial region thereof. The image-side surface of the third lens element is convex in a paraxial region thereof. The object-side surface of the fourth lens element is convex in a paraxial region thereof. The fifth lens element has negative refractive power, the object-side surface being convex, and the image-side surface being concave in a paraxial region thereof.

Abstract: Disclosed is an observation device for measuring an observation object while tracking the observation object by rotating an observation unit (10), wherein the observation device comprises a rotary unit (40) which includes: one end coupled to a support unit (20) through a first shaft rotating part (30) having a rotary shaft perpendicular to the side surface of the support unit (20); and the other end coupled to the observation unit (10) through a second shaft rotating part (50) having a rotary shaft perpendicular to the rotary shaft of the first shaft rotating part (30). Therefore, the observation device neither has a blind zone difficult to be observed nor requires rapid rotation of the rotary shaft, and thus can continuously observe objects ranging from a low-speed observation object, such as a celestial body or a planet, to a high-speed observation object, such as a satellite or a rocket.