Abstract: A negative type resist in which an alkali-soluble base resin, a crosslinking agent and an acid generating agent are dissolved in a solvent, wherein 10 through 50 wt % of the crosslinking agent and 0.5 through 20 wt % of the acid generating agent on the basis of 100 wt % of the alkali-soluble base resin are dissolved in the solvent.

Abstract: The invention relates to use of a material containing a polymerizable monomer or oligomer, the material exhibiting desirable shrinkage compensation upon polymerization. The material contains an expansion agent having a cleaving moiety with the capacity to be cleaved or fragmented by a catalytic reaction, e.g., acid catalysis. The cleavage, by increasing the number of molecules in the material, causes expansion that compensates, at least in part, for shrinkage induced by polymerization of the monomer or oligomer. The expansion agent is capable of providing compensation such that no more than 0.4%, advantageously no more than 0.2%, volume shrinkage per molar concentration of polymerized monomer functional groups occurs, where such compensation is performed at relatively low temperatures of less than 40.degree. C.

Abstract: The photorecording medium of the invention is formed by mixing a matrix precursor and a photoactive monomer, and curing the mixture to form the matrix in situ. The reaction by which the matrix precursor is polymerized during the cure is independent from the reaction by which the photoactive monomer is polymerized during writing of data. In addition, the matrix polymer and the polymer resulting from polymerization of the photoactive monomer are compatible with each other. Use of a matrix precursor and photoactive monomer that polymerize by independent reactions substantially prevents cross-reaction between the photoactive monomer and the matrix precursor during the cure and inhibition of subsequent monomer polymerization. Use of a matrix precursor and photoactive monomer that result in compatible polymers substantially avoids phase separation. And in situ formation allows fabrication of media with desirable thicknesses.

Abstract: Optical media is imaged by a combination of components for splitting a coherent beam into two co-propagating optical beams; converging the optical beams to produce a pattern of interference fringes having a pitch; varying the pitch and/or amplitude of the interference pattern fringes; axially rotating the fringes around the media; and axially rotating the co-propagating optical beams so as to maintain rotary synchronism with the axially rotating fringes as the permanent fringes are formed in the media whereby the longitudinal index of refraction is modulated along the media preferably with circular symmetry. The media is positioned as a work piece along a workpiece axis, with some of the system components translated along and/or rotated about the workpiece axis. Independently variable design parameters can, according to the preferred control system, be specified in advance with a high degree of flexibility.

Abstract: A method of forming waveguides, refractive index distributions and optical couplings automatically by light incidence, and devices obtained thereby. A non-linear optical material which has excellent properties of a large degree of freedom for an optical circuit substrate composition, etc. is used for optical circuit devices and optical circuit substrates. A photoelectric device containing an organic conjugated polymer film is deposited on a substrate by vapor deposition polymerization as at least one function layer. An optical network is provided with optical wiring for exchanging signals between processing elements selected from electronic elements, electronic apparatuses, electrooptical elements and electrooptical apparatuses.

Abstract: The present invention is directed to a holographic media that is composed of a mixture of a photosensitive substance such as a photopolymer and a porous rigid material such as an aerogel that provides a substructure to the composite material. This unique composition of matter can be utilized in a multitude of applications where a thick optically patterned wavefront modulating media is required, including as a holographic storage device. The composite material avoids the difficulties regarding shrinkage found in plain photopolymers. The rigid highly porous component is specially treated to receive the photosensitive material. This unshrinkable substructure has a plurality of very small, rigid pores that is essentially transparent at optical wavelengths and provides the matrix for the photopolymers. It provides holographic recording in both thin and thick formats without shrinkage and pattern distortion. The method of producing the composite holographic media is also disclosed.

Abstract: A method of forming optical waveguide gratings, such as in-fiber gratings, is described. The gratings are formed optically, with a phase mask being scanned by a writing laser beam to generate the grating pattern. The waveguide and phase mask are moved with respect to one another during the writing process, to vary the grating properties along the length of the grating. Relative movement in a single direction provides a chance of grating pitch, and so can be used to fabricate chirped or multi-wavelength gratings. Bi-directional dither alters the strength of the grating, and so can be used to fabricate apodised gratings.

Abstract: The invention provides a process for the generation of an antireflective bottom layer with effective reduction of substrate reflectivity and swing curve effects in lithographic applications. It involves the use of a suitably selected monomeric and/or polymeric dye which brings the real part of the refractive index into a range which is optimal for the suppression of reflection-related effects. The refractive index change is effected via anomalous dispersion, i.e., by utilizing changes in the real part of the refractive index caused by the bottom layer's absorption.

Abstract: A process for producing a polymer or a crosslinked article having a region in which the polymerization rate or crosslinking rate is varied is disclosed, comprising irradiating a photopolymerizable substance or photo-crosslinkable substance with laser light having an uneven distribution of intensity. The process is suitable for mass production of polymerization rate- or crosslinking rate-distributed articles. An arbitrary distribution pattern can be designed and formed under good control, and distribution regions having a fine shape can be formed with excellent precision. A plurality of distribution regions having a regular shape can be formed at a high density with high precision.

Abstract: A method of producing an optical waveguide grating by exposure to light. An optical waveguide having a core composed of a material wherein the refractive index changes due to exposure to UV light is formed into an optical waveguide grating by applying a grating portion formation step wherein a grating portion is formed by irradiation with UV light at a predetermined spacing, and an overall exposure step after formation of the grating portion wherein the entire grating portion is irradiated with UV light. As a result, the effective refractive index of the grating portion is changed so as to allow the central wavelength to be adjusted without changing the rejection. Consequently, the grating properties can be precisely and easily controlled.

Abstract: A method of manufacturing an optical fiber having a core portion doped with a dopant and a surrounding optical cladding portion is disclosed. The method comprises the steps of drawing a fiber from a molten extremity of a silica preform and moving the fiber along towards a device for coating it with a protective sheath. Prior to the coating step, the moving fiber is irradiated with irregularly modulated actinic radiation, thereby causing corresponding irregular variations in the refractive index of its core portion as a function of longitudinal position. The resulting fiber demonstrates a significantly reduced polarisation mode dispersion.

Abstract: A duplicating photosensitive material film is brought into close contact with an ND glass reduced in thickness so as to become flexible or a flexible sheet or an ND glass coated with a cushioning layer through an optical contacting liquid containing a surface active agent. In addition, a spacer is interposed between a hologram original plate and a duplicating photosensitive material, and a space defined by the spacer is filled with an optical contacting liquid, thereby regulating the thickness of the optical contacting liquid layer with the spacer. Therefore, when pressure is applied, the optical contacting liquid is uniformly pressed, so that it can be made uniform and thin in thickness. Accordingly, it is possible to prevent a failure of duplication of a hologram image due to undesirable flow of the optical contacting liquid.

Abstract: The application of Lippmann photographs as a unique security device on security documents, such as, e.g. identity cards, passports, credit cards is presented. The recording of such photographs requires a special type of photosensitive film layer in contact with a reflecting layer. Panchromatic photopolymer materials can be used and, after being recorded and processed, laminated to security documents. Lippmann photographs are almost impossible to copy and, certainly, cannot be copied by conventional photography or color copying machines.

Abstract: Embodiments of the invention include a method for fabricating Bragg reflector gratings using an amplitude mask and an amplitude mask apparatus for fabricating Bragg reflectors. The inventive Bragg reflector gratings have periodicities greater than conventional short period gratings but much less than conventional long period gratings. Short period, Bragg reflector gratings according to embodiments of the invention have periodicities, e.g., within the range from 1 .mu.m to 10 .mu.m. The fabrication method includes positioning an amplitude mask having appropriate slits formed therein over the photosensitive waveguide of interest and then illuminating the waveguide through the slits thereby photoinducing a periodic pattern of refractive index perturbations characteristic of a Bragg reflector. The short period, Bragg grating produced by the inventive amplitude mask is a reflective grating whose reflection characteristics approach approximately 99.99%.

Abstract: A method of avoiding unwanted phase discontinuities between adjacent sections of a long Bragg grating written section-by-section in an optical fibre uses masks with alignment parts additional to their writing parts. Each alignment part is a replica of a portion of the writing part of the adjacent mask. Light of the same wavelength as used for writing grating sections excites stronger luminescence in regions of waveguide where there has been no irradiation induced raising of the refractive index than in regions where such index raising has occurred. Therefore, for such light directed through the alignment part of the mask and into the already-written previous section of the grating, the intensity of luminescent light propagating to an end of the waveguide varies according to how well or how badly the bright fringes produced by the mask register with the corresponding irradiated portions of the written Bragg grating.

Abstract: In accordance with the invention, the index of refraction of a region of a glass body is selectively increased by treating the glass with hydrogen or deuterium, heating the hydrogenated glass to a temperature in excess of 500.degree. C., permitting the glass to rapidly cool below 100.degree. C. and exposing the region to UV radiation, preferably in the range 300 nm to 400 nm. The result is an increase in the refractive index of the irradiated region. Absorption is via a GODC band at 330 nm believed to result from a singlet to triplet transition. This band is about 1000 times weaker than the commonly used band at 240 nm. This process can be used to make and adjust a variety of optical waveguide devices such as photoinduced Bragg gratings and long period gratings.

Abstract: Methods for making plates which have columnar features approximately in the direction of light propagation which are capable of total internal reflection, a controllable numeric aperture (NA) at input and output surfaces, rotational azimuthal averaging and translation of the object plane from a back surface of the plate to a front surface of the plate and are optical equivalent of a FOFP. These plates are made from a range of materials including a variety of monomer or polymer networks. The resultant plates contain adjacent areas with differing refractive indices which result in a substrate containing a plurality of cylindrical features whose boundaries are defined by a discontinuity of refractive indices wherein the index of refraction within the cylindrical features is greater than the index of refraction at the boundaries and external to the cylindrical features.

Abstract: A method for forming a resin pattern which includes selectively polymerizing a photopolymerizable resin utilizing a light radiated from a photosensitive substance to form a desired resin pattern. A photosensitive substance layer is formed in a desired pattern on a substrate (or in a substrate when it is light permeable). The photosensitive substance absorbs an irradiation light and radiates a light of a longer wavelength than that of the irradiation light. A photopolymerizable resin layer formed on the substrate is not activated by the irradiation light but is activated by the light radiated from the photosensitive substance. The photopolymerizable resin layer is irradiated with an irradiation light capable of exciting the photosensitive substance and the photo-polymerizable resin is polymerized in the pattern of the photosensitive substance layer with the light radiated from the photosensitive substance.

Abstract: A method of forming a mirror in a waveguide, including the steps of forming a layer constituting a waveguide in a substrate and forming a mirror-finished surface at a boundary between a portion irradiated with radiation and a non-irradiated portion by obliquely irradiating a layer constituting the waveguide with radiation. The waveguide may be composed of a photosensitive material, and either the irradiated area on the non-irradiated area may be removed by solvent. The waveguide may be composed of a refractive index imaging material in which a refractive index distribution is formed by irradiation with radiation or the refractive index may be increased by heating the irradiated portion. The refractive index imaging material may include a catalyzer to assist in increasing the refractive index distribution of the irradiated area.

Abstract: A grating is induced in the core of a hydrogen-loaded high-germanium-content optical fiber using near-UV (275 nm-390 nm) laser light. An interference is generated at the core using a molded polymer phase mask with a square wave surface relief pattern. The light is directed through the phase mask, through a protective fiber coating, through the cladding, and into the core. The phase mask generates an interference pattern with a period half that of the surface relief pattern. Index of refraction changes occur at the bright fringes of the interference pattern--thus creating the grating. Advantages over existing mid-UV technology include lower fabrication costs for phase masks, simplified grating induction since fiber coatings do not need to be removed, and reduced infrared absorption caused by grating formation fiber.

Abstract: The light-induced modification in a side-chain polymer containing at least one side group whose configuration can be modified induced by light and at least one permanently shape-anisotropic side group can be amplified by warming to a temperature between the glass transition temperature and the clearing point. This effect opens up new aspects for optical data storage.

Abstract: An optical modulator includes a substrate having an electrooptic effect, an optical waveguide formed on a surface of the substrate, and a control electrode formed on the substrate, and a control electrode formed on the substrate to oppose the optical waveguide. In this optical modulator, the control electrode is formed by stacking a plurality of layers in a direction perpendicular to the substrate surface.

Abstract: Various forms of light-diffusing screen are disclosed comprising plastics sheets having surface texturing of some kind, adding to or modifying the diffusing effect. The plastics sheets may have bulk diffusing characteristics in addition to the surface texturing. The surface texturing may be produced by, for example, embossing or by molding the plastics against a textured surface such as a "brushed" surface or a ribbed or grooved surface imparting asymmetrical diffusion characteristics to the screen.

Abstract: A recording element which comprises a recording layer containing, a first charge-generating material adapted to generate a first electric charge by a supply of external energy, a first charge-transporting material for transporting the first electric charge, a charge-capturing material for capturing the first electric charge, and a material having an electro-optical effect, wherein a change in optical properties of the recording layer is caused only through an inner electric field to be generated by a delivery of electric charge between the first charge-generating material generating electric charge and the charge-capturing material capturing the electric charge.

Abstract: An optical filter for a liquid crystal display device, consisting of a polymer film which has two types of layers having different refractive index which exist alternately in a laminated state, in which a difference of refractive index between two types of layers is in the range between 0.01 and 0.1, an average thickness of each layer is at least 0.8 .mu.m and less than 2 .mu.m, and a thickness of the polymer film is in the range between 10 to 300 .mu.m, which filter can widen an angle of view of the liquid crystal display is greatly without the improvement of the liquid crystal cell, change of an addressing system or modification of the liquid crystal itself.

Abstract: A holographic recording medium comprises an acid generator capable of producing an acid upon exposure to actinic radiation; a binder; and at least one monomer or oligomer capable of undergoing cationic polymerization initiated by the acid produced from the acid generator. This recording medium is not subject to the disadvantages (for example, oxygen sensitivity) associated with radical-polymerized prior art holographic recording media.

Abstract: A method of manufacturing a semiconductor device including the steps of: forming a transparent oxide film on a light reflecting surface; forming an anti-reflective a-c film on the surface of the transparent film; and coating a photoresist film on the surface of the anti-reflective film and patterning the photoresist film, wherein the thicknesses of the anti-reflective film and the transparent film are selected so as to set a standing wave intensity I.sub.sw =I.delta./I.sub.ave to 0.2 or smaller, where I.sub.ave is an average value of light intensity in the photoresist film, and I.delta. is an amplitude of a light intensity change. A fine pattern can be formed on a highly reflective substrate with a small size variation and at a high precision.

Abstract: The method of making an optical fiber refractive index grating comprises writing the grating through the fiber coating. The method involves providing optical fiber of significantly higher photosensitivity than conventional fiber, such that the grating can be written before unacceptable darkening of the coating occurs. Such fiber is H.sub.2 and/or D.sub.2 -loaded silica-based fiber having a Ge-doped core, the fiber selected to have a germanium-oxygen deficiency center content that provides the fiber with a photosensitivity that is at least twice as large as that of an otherwise identical, conventionally prepared, optical fiber. The fiber typically is drawn from a preform, at least a portion of which was exposed to a reducing atmosphere at an elevated temperature.

Abstract: A photorefractive (PR) device comprises of a layer of a novel photorefractive polymer composite sandwiched inbetween two transparent electrodes. The PR polymer composite comprises a photoconducting polymer, a photosensitizer, a novel second-order, non-linear optical chromophore, and a plasticizer in an amount sufficient to provide the PR polymer composite with a glass transition temperature below about 45.degree. C. The PR polymer composite is capable of internally storing image patterns generated by interfering two coherent light beams inside the material. The PR polymer composite shows high diffraction efficiencies (near 100%) and high net two-coupling gain (>200 cm.sup.-1). The writing of information is reversible. Consequently, the device is suitable for read/write holographic storage and real-time image processing applications, and is capable of being poled at essentially room temperature.

Abstract: A grating is induced in the core of a hydrogen-loaded high-germanium-content optical fiber using near-UV (275 nm-390 nm) laser light. An interference pattern is generated at the core using a molded polymer phase mask with a square wave surface relief pattern. The light is directed through the phase mask, through a protective fiber coating, through the cladding, and into the core. The phase mask generates an interference pattern with a period half that of the surface relief pattern. Index of refraction changes occur at the bright fringes of the interference pattern--thus creating the grating. Advantages over existing mid-UV technology include lower fabrication costs for phase masks, simplified grating induction since fiber coatings do not need to be removed, and reduced infrared absorption caused by grating formation in the fiber.

Abstract: Broad band reflection holograms and process for producing broad band reflection holograms in photosensitive elements comprising photopolymer photosensitive layers are disclosed. These holograms may be used to form very bright display holograms, ultraviolet, visible and infrared rejection filters, and holographic security devices, as well as may be used in a wide variety of other applications.

Abstract: The present invention provides a photosensitive composition for volume hologram recording, comprising the following components:(A) a cationic polymerizable compound and a radical polymerizable compound,(B) a cationic polymerization initiating material, and(C) a radical polymerization initiating material, as an essential component, wherein at least one of the cationic polymerizable compound and radical polymerizable compound of the component contains a siloxane group, and a difference in refractive index between the cationic polymerizable compound and radical polymerizable compound is not less than 0.01.

Abstract: Ferroelectric materials are disclosed as reversible holographic recording media (25) for use in two-photon recording systems. The ferroelectric materials disclosed herein provide long-lived electronic states intermediate the ferroelectric material's valence and conduction bands. These intermediate states have a sufficiently long life (on the order of 1 to 100 milliseconds) that low-power continuous wave ("cw") lasers (1) can be used to record interference patterns on them. Thus, two-photon holographic recording systems are also disclosed which do not require high-power, short pulse length, mode-locked or Q-switched lasers. Rather, the disclosed holographic recording systems employ visible and near IR cw lasers such as diode lasers.The disclosed two-photon holographic recording systems provide for absorption of a first photon which excites electrons of holographic recording media to an intermediate state.

Abstract: A photosensitive recording material comprising a solvent-soluble, thermosetting epoxy oligomer capable of cationic polymerization, an aliphatic monomer having at least one ethylenically unsaturated bond, the monomer being liquid at normal temperature and pressure, having a boiling point of 100.degree. C. or above at normal pressure and being capable of radical polymerization, a photoinitiator selected from the group consisting of i) a first photoinitiator capable of simultaneously generating a radical species that activates radical polymerization and a Br.o slashed.nsted acid or Lewis acid that activates cationic polymerization, upon exposure to actinic radiation, and ii) a second photoinitiator comprised of a radical polymerization photoinitiator capable of generating a radical species that activates radical polymerization upon exposure to actinic radiation and a cationic polymerization photoinitiator capable of generating a Br.o slashed.

Abstract: A diffraction grating structure for coupling light into or out of a high refractive index waveguide layer on a carrier substrate is formed by irradiating the carrier substrate and/or the layer with UV laser light that is subject to simultaneous, spatially periodic intensity modulation. The modulation may be achieved, for example, by a biprism. The modulated UV light has the effect of periodically modulating the local refractive index of the waveguide layer or of the surface of the substrate to form the diffraction grating.

Abstract: A hologram forming system for forming holograms on multiple exposures is provided. In this system, a holographic recording medium is exposed to light beams at least twice at incident angles different between exposures. The incident angle during each exposure process is determined in a given relation to the thickness of the holographic recording medium which tends to vary as the exposure process is repeated so that the reconstruction wavelengths match with target values without shifting between image colors during reconstruction of the hologram.

Abstract: Disclosed is a photosensitive composition for volume hologram recording which is used for recording an interference fringe produced by a laser beam or a light having excellent coherence, as fringes having different refractive index. The composition comprising:(a) a cationic polymerizable compound which is liquid at ambient temperature;(b) a radical polymerizable compound;(c) a radical photopolymerization initiator composition sensitized by a laser beam or a light having excellent coherence which has a specific wavelength to polymerize the ingredient (b); and(d) a cationic photopolymerization initiator composition which shows low photosensitivity to the light having a specific wavelength and is sensitized by a light having the other wavelength to polymerize the ingredient (a), wherein an average refractive index of the ingredient (a) is smaller than that of the ingredient (b). A process for producing the photosensitive composition is also disclosed.

Abstract: A duplicating photosensitive material film is brought into close contact with an ND glass reduced in thickness so as to become flexible or a flexible sheet or an ND glass coated with a cushioning layer through an optical contacting liquid containing a surface active agent. In addition, a spacer is interposed between a hologram original plate and a duplicating photosensitive material, and a space defined by the spacer is filled with an optical contacting liquid, thereby regulating the thickness of the optical contacting liquid layer with the spacer. Therefore, when pressure is applied, the optical contacting liquid is uniformly pressed, so that it can be made uniform and thin in thickness. Accordingly, it is possible to prevent a failure of duplication of a hologram image due to undesirable flow of the optical contacting liquid.

Abstract: The invention discloses that a photograph with a 3-dimensional image results when the non-angular reflector (of mercury) used in the Lippmann process of color photography is replaced by an angular reflector; the preferred form of the angular reflector is a retro-reflector.A photographic system is described which produces photographs with 3-dimensional images. The photo-sensitive element records the interference patterns of light waves, and the system is an improvement over the Lippmann process of color photography which produces photographs with 2-dimensional images. A photographic system is also described that produces a photograph with a 3-dimensional image from 2-dimensional cross sections of a subject; the system is useful in medical imaging. During exposure, motion of more than one wavelength of light is permissible between the subject and lens or the lens and the photo-sensitive element.These improvements result from the use of a particular type of angular reflector which is a retro-reflecting sheet.

Abstract: A process of forming a single color image comprising:a) imagewise exposing, by means of a laser, a dye-ablative recording element comprising a support having thereon, in order, a hydrophilic dye-receiving layer, a hydrophobic dye-barrier layer, and a hydrophilic, water-soluble, infrared-absorbing layer which absorbs at a given wavelength of the laser used to expose the element, thereby imagewise heating the infrared-absorbing layer and the dye-barrier layer, causing them to ablate;b) removing the ablated infrared-absorbing layer and dye-barrier layer material;c) contacting the imagewise-exposed element with an aqueous ink solution and thereby removing the remaining infrared-absorbing layer; andd) drying the element to obtain a single color image in the ablative recording element.

Abstract: The present invention is predicated upon the discovery by applicants of a relationship describing thermal decay of radiation-induced index changes and a mechanism which permits stabilization by accelerated aging. Specifically, the induced index change decays in proportion to 1/(1+At.sup..alpha.) where A and .alpha. are functions of temperature, and the decay can be accelerated by heat treatment. As a consequence, the extent of decay can be determined for arbitrary time and temperature and, significantly, an appropriate heat treatment can be scheduled for making a device stable within predeterminable limits.

Abstract: Recognizing the rate-determining nature of the coating removal and recoating steps, applicants have demonstrated that with proper combination of low absorbing polymer, glass and low intensity radiation, UV-induced gratings can be side-written into polymer coated fibers without removing the polymer, thus permitting up the possibility of high speed fabrication of fiber gratings.

Abstract: The present invention relates to a three-component optical photorefractive article having improved diffraction efficiency. The article comprises (i) nonphotoconductive polymer, (ii) benzimidazoline, and (iii) a sensitizer.

Abstract: A hologram recording device, which comprises a recording layer of a polymer composition a photoconductive element, a second-order super-polarization element and an electron or hole capturing material and having a non-centro symmetric structure is disclosed. Transparent electrode layers are provided on each side of the recording layer. The hologram recording device is capable of space light modulation and real time hologram recording. Also disclosed is a method of manufacturing the hologram recording device and a method of hologram recording using the device. The hologram recording material is of a polymer composition a photoconductive element, a second-order super-polarization element and an electron or hole capturing element. The polymer composition has a non-centro symmetric structure. The hologram recording device according to the invention comprises a recording layer of a polymer composition including a photoconductive element and a second-order super-polarization element.

Abstract: Flat materials made from a polymer with a backbone and side groups branching off the backbone (side group polymer), which polymer has the following structural features (1) to (3):(1) the side group polymer contains at least one photoinducibly configuration-changing side group;(2) the side group polymer contains at least one permanently conformationally anisotropic side group with high anisotropy of molecular polarisability which differs from (1);(3) the side group polymer contains flexible spacer groups between the backbone and the side groups (1) and (2);wherein the flat material in the glassy state of the side group polymers is optically isotropic, transparent, non-scattering and amorphous before irradiation and, after irradiation, is transparent and durably birefringent and dichroic due to a reversible, photoinduced alignment of the side groups (1) and (2) in the glassy state, may be purposefully modified in terms of their optical properties by the action of light.

Abstract: Optically active (optically non-linear or electro-optically active) waveguides are formed by depositing a layer of organic material, typically polymeric material, comprising one or more opticaly active components, and subjecting predetermined regions of the layer to actinic radiation to alter the refractive index of these regions.

Abstract: A holographic storage media (10) is fabricated from a thin layer of photopolymer recording media. The photopolymer recording media is disposed between a substrate (48) and a capping layer (56). The media (10) is divided into a plurality of storage regions (54), which are formed within wells (52) to isolate each of the regions (54). During a record operation, a pumping operation is first performed to remove oxygen molecules from the media by bombarding the select region that is to have an interference pattern recorded therein with photons for a predetermined duration of time. Once the oxygen molecules have been depleted, then a data beam is generated with data superimposed thereon and a reference beam generated for interference with the data beam in the storage region (54). This results in the recording of an interference pattern.

Abstract: Holographic flake pigments, processes for making the pigments, decorative coatings comprising the pigments, and articles comprising the decorative coatings are disclosed. The pigment comprises particles that (1) comprise an organic polymer and further comprise one or more volume phase holograms; and (2) have a thickness of about 1 micrometer to about 100 micrometers, an average diameter of about 10 micrometers to about 300 micrometers, and a thickness to diameter ratio of about 1:2 to about 1:60.

Abstract: Holographic flake pigments, processes for making the pigments, decorative coatings comprising the pigments, and articles comprising the decorative coatings are disclosed. The pigment comprises particles that (1) comprise an organic polymer and further comprise one or more volume phase holograms; and (2) have a thickness of about 1 micrometer to about 100 micrometers, an average diameter of about 10 micrometers to about 300 micrometers, and a thickness to diameter ratio of about 1:2 to about 1:60.

Abstract: This invention involves improvements in interference film photography including the use of indium or gallium reflecting layers.