Abstract: A holographic recording medium exhibiting a high recording sensitivity without execution of reduction treatment. A system records information on the holographic recording medium by using a gating light within a wavelength band causing less optical damage to the holographic recording medium. The holographic recording medium includes a single crystal of lithium niobate (LiNbO3) or lithium tantalate (LiTaO3) containing Mn as a dopant.

Abstract: A ferroelectric material in which the refractive index change can be induced by irradiation with light at two different wavelengths without performing a reduction treatment or doping impurities. The ferroelectric material of the invention in which the refractive index change is induced by irradiation with light at two different wavelengths is a lithium tantalate single crystal with the composition of Li2O/(Li2O+Ta2O5)=0.4966 to 0.4995. Preferably, the ferroelectric material is a lithium tantalate single crystal with the composition of Li2O/(Li2O+Ta2O5)=0.4974 to 0.4989. Preferably, the infrared absorption coefficient in the [OH] stretching mode falls within a range of 0 cm−1 to 0.15 cm−1 (0 cm−1 and 0.15 cm−1 are included in the range).

Abstract: A method for treating a photorefractive effect of an optical device, which comprises irradiating an optical device comprising a lithium niobate single crystal or a lithium tantalate single crystal with an ultraviolet light having a wavelength of at least 300 nm and at most 400 nm so as to suppress and control a photo-induced refractive index change (photorefractive effect) caused on the device.

Abstract: A method for treating a photorefractive effect of an optical device, which comprises irradiating an optical device comprising a lithium niobate single crystal or a lithium tantalate single crystal with an ultraviolet light having a wavelength of at least 300 nm and at most 400 nm so as to suppress and control a photo-induced refractive index change (photorefractive effect) caused on the device.

Abstract: A holographic recording medium has a high recording sensitivity without execution of reduction treatment. A system records information on the holographic recording medium by using a gating light within a wavelength band causing less optical damage to the holographic recording medium. The holographic recording medium comprises a single crystal of lithium niobate (LiNbO3) or lithium tantalate (LiTaO3) containing Mn as a dopant.

Abstract: An optically functional device comprising a ferroelectric single crystal substrate and polarization-inverted structures formed at portions of the substrate at a temperature of not higher than the Curie temperature by an electron beam scanning irradiation method or a voltage application method and designed to control light passed through the polarization-inverted portions, wherein a LiNbO3 crystal having a molar ratio of Li/Nb within a range of from 0.95 to 1.01, is used as the substrate, so that the propagation loss of light passed through the polarization-inverted portions immediately after formation of the polarization-inverted structures, is not more than 2%.

Abstract: A semiconductor device has a gate-insulating film formed on a semiconductor substrate. Gate electrodes comprised of P- and N-type polysilicon thin films and thin conductive films are formed over the gate-insulating film. The P- and N-type polysilicon thin films are doped with impurities at an impurity concentration sufficient to prevent depletion layers from being formed in the P- and N-type polysilicon thin films when a voltage is applied between each of the conductive thin films and the semiconductor substrate. Source and drain regions are formed over the semiconductor substrate in spaced-apart relation to one another and on opposite sides of the gate electrodes.

Abstract: A monoazo lake pigment composition containing a monoazo lake pigment obtained from a laked pigment aqueous slurry prepared by conducting coupling of a diazo component obtained by diazotizing an aromatic amine having a soluble group and a coupler component and conducting laking after or simultaneously with the coupling, wherein the laking is carried out in the presence of a water-soluble acrylic polymer in an amount of 0.1 to 40 parts by weight per 100 parts of the above coupler component, and a gravure ink containing the above pigment composition and a gravure ink vehicle.

Abstract: A single crystal of lithium niobate or lithium tantalate may be grown from a melt of a composition having a molar excess of Li compared to a melt having the stoichiometric amount of lithium, and having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/(Ta2O5+Li2O) within a range of at least 0.490 and less than 0.500. The single crystal also has at least one element selected from the group consisting of Mg, Zn, Sc and In, in an amount of from 0.1 to 3.0 mol % based on the total amount of the elements, Nb and Li, or the total amount of the elements, Ta and Li.

Abstract: A photorefractive material provides a high photosensitivity without reduction. The material comprises a single crystal of terbium (Tb)-doped niobate or tantalate. The single crystal is a single crystal of lithium niobate (LiNbO3) whose molar fraction of [Li2O]/([Li2O]+[Nb2O5]) lies in a range of 0.482 to 0.505, or a single crystal of lithium tantalate (LiTaO3) whose molar fraction of [Li2O]/([Li2O]+[Ta2O5]) lies in a range of 0.482 to 0.505. The amount of terbium added in the photorefractive material ranges from 10 weight ppm to 1000 weight ppm.

Abstract: An optically functional device comprising a ferroelectric single crystal substrate and polarization-inverted structures formed at portions of the substrate at a temperature of not higher than the Curie temperature by an electron beam scanning irradiation method or a voltage application method and designed to control light passed through the polarization-inverted portions, wherein a LiTaO3 crystal having a molar ratio of Li/Ta within a range of from 0.95 to 1.02, is used as the substrate, so that the propagation loss of light passed through the polarization-inverted portions immediately after formation of the polarization-inverted structures, is not more than 2%.

Abstract: Disclosed is a pretreatment method for a hologram recording medium used in the hologram recording method in which information signals loaded on signal beam are recorded by injecting coherent signal beam and reference beam to the hologram recording medium which is exposed to first light having first wavelength of ultraviolet band or short-wavelength visible light band in advance in order to generate light-induced absorption, wherein the coherent signal beam and reference beam each having longer wavelength than the first wavelength. The pretreatment method comprises subjecting the hologram recording medium to oxidation treatment prior to the irradiation of the first light has been completed.

Abstract: A hologram recording apparatus is capable of directing interferable signal light and reference light into a hologram recording medium to record an information signal carried by the signal light. The hologram recording medium is sensitive to a first light at a first wavelength in an ultraviolet or short-wavelength visible light band to develop light induced absorption. The apparatus includes a light source for irradiating the hologram recording medium with the first light, and a laser light source for irradiating the hologram recording medium with signal light and reference light at a second wavelength longer than the first wavelength after the first light is irradiated.

Abstract: A semiconductor device and method of fabricating the device are described. The subthreshold factor of a semiconductor device is suppressed. Also, the leakage current under lower voltage operation is suppressed. The method comprises the steps of: forming a gate-insulating film on a surface of a semiconductor substrate; forming a thin film of silicon on said gate-insulating film; implanting ions of a P-type impurity into the silicon film of silicon; heat-treating the substrate at a temperature of 700 to 900° C. to make the silicon film P-type; forming a silicide film on the silicon film; forming a gate electrode pattern; forming a CVD-grown dielectric film 5-1000 Å thick over the whole surface of the semiconductor substrate; implanting impurity ions into the surface of the semiconductor substrate, using the gate electrode as a mask to form source/drain regions.

Abstract: In a damping force generator for a hydraulic damper, the valve is protected from pressure rise in the damper and its durability is thereby enhanced. The damping force characteristics can be vary in stepwise fashion by providing a main leaf valve 21 and a sub-leaf valve which closes an opening 21A formed in the main leaf valve 21, and the approximate mid-point of the main leaf valve 21 is supported by a plurality of intermediate seat surfaces 16 from the side of a port 13. The outer circumference of a main leaf valve 64 is supported by an outer circumferential seat surface 62, and the outer circumference of a sub-leaf valve 65 extends outwards to the vicinity of a part where the outer circumference of the main leaf valve 64 and the outer circumferential seat surface 62 overlap.

Abstract: A two-color holographic recording apparatus reduces error signals possibly included in reproduced digital data signals. The two-color holographic recording apparatus has first, second and third light shutters for passing or blocking gate light, signal light and reference light incident on a recording medium respectively, and a controller for controlling the respective states of the first, second and third light shutters.

Abstract: Disclosed is a liquid epoxy resin composition for sealing a semiconductor device which comprises (A) a cyanic acid ester, (B) an epoxy resin, (C) an inorganic filler, (D) a metal chelate and/or a metal salt, and at least one of (E1) an acid anhydride, (E2) a dihydrazide compound and (F) a silicone resin gel, wherein at least one of components A and B is liquid at room temperature, component E1 is liquid at room temperature, and the weight ratio of component C to the total weight of the composition, the weight ratio of component A to component B, and the weight ratio of component E1, E2 or F to the total weight of the composition except component C each ranges a specific ratio.

Abstract: A stoichiometric single crystal of lithium niobate or lithium tantalate is produced by pulling a single crystal of lithium niobate or lithium tantalate having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/ (Ta2O5+Li2O) of at least 0.490 and less than 0.500, from a melt of a composition having a molar excess of Li over a stoichiometric composition of lithium niobate or lithium tantalate. The single crystal has 0.1 to 3 mol % of at least one element selected from the group consisting of Mg, Zn, Sc and In based on a total amount of elements Nb and Li, or a total amount of elements Ta and Li. The single crystal has substantially no absorption in the visible light region.

Abstract: A semiconductor device fabrication method comprises the steps of forming a gate insulating film on a surface of a semiconductor substrate, forming a polysilicon film on the gate insulating film, and implanting B or BF2 impurity ions into the polysilicon film. The polysilicon film is then heat-treated at a temperature of 700-900° C. to activate and diffuse the implanted B or BF2 impurity ions. Thereafter, a silicide film is formed on the heat-treated polysilicon film. The silicide film and the heat-treated polysilicon film are then etched to form a gate electrode on the gate insulating film. A CVD-grown dielectric film having a thickness of 5 to 1000 Å is then formed over the whole surface of the semiconductor substrate and the gate electrode. B or BF2 impurity ions are then implanted into the surface of the semiconductor substrate, using the gate electrode as a mask, to form source/drain regions.

Abstract: A semiconductor device has a protection MOS transistor and an operating MOS transistor connected in parallel with the protection MOS transistor. The operating MOS transistor has a gate electrode and a drain region surrounded by the gate electrode.