A holographic optical element and a manufacturing method thereof, an image reconstruction method, and augmented reality glasses are disclosed. The holographic optical element includes a substrate, and a recording material layer in which at least two groups of interference fringes are recorded; each group includes a first interference fringe formed by a first signal light and a first reference light respectively incident from opposite sides of the recording material layer, and a second interference fringe formed by a second signal light and a second reference light respectively incident from opposite sides of the recording material layer; the second signal light passes through a lens before incidence; incident angles of the first signal light and the second reference light are equal; incident directions of the first signal light corresponding to respective groups are different, and focal lengths of the lenses are not equal.

A system or device includes a member structure, a plurality of flexible members, and a plurality of tips disposed at ends of the flexible members. The member structure includes an ultrasonic emitter configured to emit an ultrasonic imaging signal. The plurality of flexible members are coupled to the member structure. The plurality of tips are disposed at ends of the flexible members. At least one tip of the plurality of tips includes an image sensor configured to receive an infrared exit signal.

An optical coupler includes a plurality of volume gratings in a substrate. The gratings include an array of fringes extending along length and thickness dimensions of the substrate. A difference between a refractive index of the fringes and a refractive index of the substrate depends on a depth coordinate along the thickness dimension of the substrate. A dependence of the difference on the depth coordinate has a bell-shaped function which suppresses ghost image formation due to optical crosstalk between gratings of neighboring spatial pitches.

A low-cost digital holography microscope (DHM) that is capable of performing inspection at high speed while accurately inspecting an inspection object at high resolution, an inspection method using the DHM, and a method of manufacturing a semiconductor device by using the DHM are provided. The DHM includes: a light source configured to generate and output light; a beam splitter configured to cause the light to be incident on an inspection object and output reflected light from the inspection object; and a detector configured to detect the reflected light, wherein, when the reflected light includes interference light, the detector generates a hologram of the interference light, and wherein no lens is present in a path from the light source to the detector.

The present disclosure relates to improved holographic reconstruction device and a method. In one aspect, the present disclosure relates to improved holographic reconstruction device and method that can measure a digital hologram regardless of optical characteristics of an object to be measured, by an all-in-one type system integrating a transmissive system that measures an object transmitting light and a reflective system that measures an object reflecting light.

A grating coupler may be fabricated by exposing a photopolymer layer to grating forming light for forming periodic refractive index variations in the photopolymer layer. The photopolymer layer may be exposed to apodization light for reducing an amplitude of the periodic refractive index variations in a spatially-selective manner. The apodization may also be achieved or facilitated by subjecting outer surface(s) of the photopolymer layer to a chemically reactive agent that causes the refractive index contrast to be reduced near the surface(s) of application. The apodized refractive index profile of the gratings facilitates the reduction of optical crosstalk between different gratings of the grating coupler.

Example embodiments relate to imaging devices for in-line holographic imaging of objects. One embodiment includes an imaging device for in-line holographic imaging of an object. The imaging device includes a set of light sources configured to output light in confined illumination cones. The imaging device also includes an image sensor that includes a set of light-detecting elements. The set of light sources are configured to output light such that the confined illumination cones are arranged side-by-side and illuminate a specific part of the object. The image sensor is arranged such that the light-detecting elements detect a plurality of interference patterns. Each interference pattern is formed by diffracted light from the object originating from a single light source and undiffracted light from the same single light source. At least a subset of the set of light-detecting elements is arranged to detect light relating to not more than one interference pattern.

A device (110) for illuminating a particle comprises: a light waveguide (112; 412a, 412b; 512a, 512b) arranged on a substrate (114); an output coupler (118) configured to output a light beam (150; 450a, 450b; 550a, 550b) forming a sheet-like shape having a cross-section which has an extension in a first direction being larger than a size of a particle; and a fluidic channel (116; 416; 516) arranged on the substrate (114) for guiding a flow of particles along a longitudinal direction of the fluidic channel (116; 416; 516); wherein the sheet-like shape of the light beam (150; 450a, 450b; 550a, 550b) is arranged within the fluidic channel (116; 416; 516) and the first direction of the cross-section of the light beam (150; 450a, 450b; 550a, 550b) forms an angle to the longitudinal direction of the fluidic channel (116; 416; 516). A system (100) for imaging the particle comprises the device, an array (130; 430a, 430b; 530) of light-detecting elements (132; 432a, 432b; 532); and a lens (120) to converge light towards the array (130; 430a, 430b; 530) such that each light-detecting element (132; 432a, 432b; 532) detects light originating from a corresponding position in the fluidic channel (116; 416; 516).

A device for producing a master diffraction grating includes a light source unit and a reflecting member 11. The light source unit forms a first interference fringe by irradiating a substrate surface of a master substrate 101 with light. The reflecting member 11 reflects the light from the light source unit reflected on the substrate surface of the master substrate 101 and guides the light again to the substrate surface side to form a second interference fringe. A resist pattern based on the first interference fringe and the second interference fringe is formed on the substrate surface of the master substrate 101.

A method for producing a computer-generated hologram including producing a reference beam, producing an object beam, applying computer-generated information regarding the hologram to the object beam, overlapping the object beam and the reference beam on or in a light-sensitive recording medium in order to apply the hologram by exposure, wherein several portions of the light-sensitive recording medium are exposed, one after the other, to the object beam and the reference beam simultaneously in order to produce a plurality of sub-holograms, wherein the angle of incidence at which the reference beam hits the surface of a first portion of the recording medium is different from the angle of incidence at which the reference beam hits the surface of a second portion of the recording medium. A change in the angle of incidence of the reference beam is achieved by changing the point of incidence of the reference beam on a lens.