A laser beam (L50) is reflected by a light beam scanning device (60) and irradiated onto a hologram recording medium (45). On the hologram recording medium (45), an image (35) of a linear scatter body is recorded as a hologram by using reference light that converges on a scanning origin (B). The light beam scanning device (60) bends the laser beam (L50) at the scanning origin (B) and irradiates the laser beam onto the hologram recording medium (45). At this time, by changing a bending mode of the laser beam with time, an irradiation position of the bent laser beam (L60) on the hologram recording medium (45) is changed with time. Diffracted light (L45) from the hologram recording medium (45) produces a reproduction image (35) of the linear scatter body on a light receiving surface (R) of the stage 210. When an object is placed on the light receiving surface (R), a line pattern is projected by hologram reproduction light, so that the projected image is captured and a three-dimensional shape of the object is measured.

A dynamic image diffractive device product, including: a transparent substrate; and a hardened resin pattern layer adhered with a surface of the transparent substrate; wherein the hardened resin pattern layer has a plurality of grating pattern regions, so that when the transparent substrate is moved by a driving device to have each pattern region of the plurality of grating pattern regions illuminated in turn by a laser light source, a transmitted light beam from the transparent substrate will present a dynamic image on a surface of an external object.

A digital holographic image-taking apparatus includes an illumination portion having a light emission surface for emitting illumination light toward an object, the illumination light having a specific wavelength in a coherent plane waveform; and an image sensor having an pixel array including two-dimensionally arranged pixels, the image sensor capturing an interference pattern generated based on the illumination light having acted on the object, in which the following conditional expression is satisfied: 0.0000001<Z.sup.2/S<16, where S represents the area of the light emission surface, and Z represents the distance from the light emission surface to the pixel array.

The present application provides a replicating method and a replicating device of a transmission type holographic optical element capable of mass-replicating the transmission type holographic optical element by a continuous and economical process.

An illumination apparatus using a coherent light source, comprising: a coherent light source that generates a coherent light beam, a microlens array including a collection of a large number of independent lenses; and a light beam scanning device that irradiates the light beam onto the microlens array and carries out scanning so that an irradiation position and an irradiation direction of the light beam on the microlens array changes with time. Each of the independent lenses included in the microlens array has a function of refracting light irradiated from the light beam scanning device and forming an irradiation region on a light receiving surface. The light receiving surface is not a refractive element, and is configured so that irradiation regions formed by the independent lenses become substantially a same common region on the light receiving surface. The irradiation regions being irradiated by light which is refracted by the independent lenses.

Multiple pairs of substrate-guided wave-based holograms (SGWHs) are laminated to a common thin substrate to form a transparent substrate-guided wave-based holographic CHMSL (SGWHC) that diffracts playback LED illumination over a wide angular range. This device is made pursuant to a technique that includes the steps of recording a first set of SGWHs with one setup, that upon playback, will couple and guide the diffracted light inside the substrate, and a second set of SGWHs recorded with another setup, that will diffract and couple the guided light out.

The invention relates to a method of creation of three-dimensional alignment patterns that includes providing a layer of optically recordable and polarization sensitive material having a thickness that is greater than, or equal to, a predefined thickness, and concurrently illuminating the optically recordable medium with two coherent beam of same or different polarization with predetermined angle between the beams such that the said beams impinge from the same side or from the opposite sides upon the layer of the recordable material. The invention further relates to polarization volume holograms based on the said alignment patterns and polarization holographic element including a single layer or a stack of several layers of optically recordable materials containing single or multiple polarization volume holograms.

Provided is a hologram transcription apparatus including: an exposure part; and a light source part for irradiating light to the exposure part. Here, the exposure part includes a transfer unit for transferring a hologram film, and the exposure part is rotatable to change an angle formed with the light.

A system includes a laser emitting a laser beam, a beam expander expanding the laser beam, a beam splitter prism splitting the expanded laser beam into first and second split light beams, a liquid crystal box containing polymer-dispersed liquid crystal, first and second reflectors reflecting the first and second split light beams to the liquid crystal box, respectively, and an attenuator arranged on an optical path between the beam expander and the liquid crystal box. The attenuator gradually attenuates at least one of the laser beam, the expanded laser beam, the first split light beam, or the second split light beam along a first set curve. The first split light beam and the second split light beam form interference fringes at the liquid crystal box to expose the polymer-dispersed liquid crystal to form a polymer-dispersed liquid crystal holographic grating having a diffraction efficiency decreasing along a second set curve.

A method of forming a filter, comprising the steps of:selecting at least a first wavelength corresponding to a predetermined laser threat and having a first colour in the visible spectrum;providing a generally transparent substrate and forming a first notch filter region therein configured to substantially block incident radiation thereon of wavelengths within a first predetermined wavelength band including said first wavelength;selecting a second wavelength having a second colour in the visible spectrum and forming a colour balancing notch filter region in said substrate configured to block incident radiation thereon of wavelengths within a wavelength band including said second wavelength, thereby to balance or neutralise any colour distortion of said substrate caused by said first notch filter region.