Abstract: A porous silica material disclosed in the present application is a porous silica material in which a plurality of silica particles are connected to one another three-dimensionally, wherein: a density of the porous silica material is less than 220 kg/m3; a particle diameter of the silica particles is 3.5 nm or more; and the water content of the porous silica material is 8 wt % or less.

Abstract: An optical microphone for detecting an acoustic wave propagating through an environmental fluid by using a light wave, includes: an acoustic wave receiving section having a propagation medium portion through which an acoustic wave propagate and a first support portion for supporting the propagation medium portion; a light source for outputting a light wave so that the light wave passes through the propagation medium portion across the acoustic wave propagating through the propagation medium portion; a light-blocking portion having an edge line for splitting the light wave having passed through the propagation medium portion into a blocked portion and a non-blocked portion; and a photoelectric conversion section for receiving a portion of the light wave having passed through the propagation medium portion which has not been blocked by the light-blocking portion to output an electric signal.

Abstract: A method of producing a porous silica material includes: preparing a raw material solution containing silicon alkoxides including diisobutyldimethoxysilane and tetramethoxysilane in such a mass ratio that a mass of the diisobutyldimethoxysilane is 0.25 or more and 1 or less per mass of the tetramethoxysilane, and a solvent; obtaining a wet gel by adding, to the raw material solution, an aqueous solution containing a catalyst for promoting hydrolysis and condensation polymerization of the silicon alkoxides, the aqueous solution having a pH of 8.9 or more and 11.3 or less; washing the wet gel; and drying the washed wet gel under supercritical conditions.

Abstract: An acousto-optic imaging system includes: an ultrasonic wave source for irradiating an imaged object with an ultrasonic wave; an acoustic lens for converting a scattered wave of the ultrasonic wave to a plane wave; a light-transmitting acoustic medium provided in an area on an opposite side of the imaged object with respect to the acoustic lens; a light source for outputting a monochromatic light plane wave; an image-forming lens arranged so as to condense diffraction light of the monochromatic light plane wave which is produced in the light-transmitting acoustic medium; an image-receiving section for obtaining an optical image formed by the image-forming lens; and a distortion compensation section for correcting a distortion of the optical image or a distortion.

Abstract: A method of producing a porous silica material includes: preparing a raw material solution containing silicon alkoxides including diisobutyldimethoxysilane and tetramethoxysilane in such a mass ratio that a mass of the diisobutyldimethoxysilane is 0.25 or more and 1 or less per mass of the tetramethoxysilane, and a solvent; obtaining a wet gel by adding, to the raw material solution, an aqueous solution containing a catalyst for promoting hydrolysis and condensation polymerization of the silicon alkoxides, the aqueous solution having a pH of 8.9 or more and 11.3 or less; washing the wet gel; and drying the washed wet gel under supercritical conditions.

Abstract: An optical microphone includes: an acousto-optic medium section having a pair of principal surfaces and at least one lateral surface provided therebetween; a restraint section which is in contact with the at least one lateral surface for preventing a shape change of the acousto-optic medium section; and a light emitting section for emitting a light wave so as to propagate through the acousto-optic medium section between the pair of principal surfaces. The pair of principal surfaces are in contact with an environmental fluid through which an acoustic wave to be detected is propagating and are capable of freely vibrating, and an optical path length variation of a light wave propagating through the acousto-optic medium section, which is caused by the acoustic wave that comes into the acousto-optic medium section from at least one of the pair of principal surfaces and propagates through the acousto-optic medium section, is detected.

Abstract: An acousto-optic imaging device disclosed in the present application includes: an acoustic wave source; an acoustic lens system for converting a scattered wave produced by irradiation of an object with an acoustic wave emitted from the acoustic wave source into a predetermined converged state; an acousto-optic medium section which is arranged such that a scattered wave transmitted through the acoustic lens system is incident on the acousto-optic medium section; a light source for emitting a light beam which is formed by a plurality of superposed monochromatic light rays traveling in different directions; an image formation lens system for condensing diffracted light of a plurality of the monochromatic plane wave light rays produced at the acousto-optic medium section; and an image receiving section for detecting light condensed by the image formation lens system to output an electric signal.

Abstract: A reflective plate 72 is arranged so as to reflect infrared rays, radiated from a heating wire 71, outside of a heater 70 and may be made of steel. A number of cavities 73 are arranged on the surface of the reflective plate 72. Since the cavities 73 have an aspect ratio of 0.17 to 0.7, the infrared reflectance can be increased compared to a reflector with no cavities.

Abstract: An optical microphone includes: a light source; a first polarizer for allowing linearly-polarized light, of light output from the light source, to pass therethrough; a second polarizer for allowing linearly-polarized light having a different polarization plane from the first polarizer to pass therethrough; a sound-receiving section including an acoustic medium having a smaller sound velocity than the air, wherein an acoustic signal propagates through the acoustic medium, the sound-receiving section being arranged so that the linearly-polarized light from the first polarizer passes through the acoustic medium and enters the second polarizer; and a photodetector for converting an intensity of light having passed through the second polarizer to an electric signal, wherein between the first polarizer and the second polarizer, the linearly-polarized light having passed through the first polarizer is given different phase shifts in two orthogonal directions which are each different from a polarization direction.

Abstract: A porous silica material in which silica particles are connected to one another three-dimensionally, wherein: the porous silica material includes a through hole including first pores smaller than a mean free path of an air, and second pores larger than the first pores; the porous silica material has a density of 100 kg/m3 or more and 300 kg/m3 or the silica particles.

Abstract: There is provided an optical microphone for detecting an acoustic wave propagating in an ambient fluid, the optical microphone including: a propagation medium section; a light source for emitting a light wave to be transmitted through a diffraction region in the propagation medium section; and a photoelectric conversion section for detecting the light wave having been transmitted through the propagation medium section. A first acoustic wave which is a portion of the acoustic wave and a second acoustic wave which is another portion thereof are allowed to propagate in the propagation medium section so as to simultaneously arrive at the diffraction region, and an interference component between a +1st order diffracted light wave and a ?1st order diffracted light wave of the light wave generated based on a refractive index distribution of the propagation medium occurring in the diffraction region.

Abstract: A reflective plate 72 is arranged so as to reflect infrared rays, radiated from a heating wire 71, outside of a heater 70 and may be made of steel. A number of cavities 73 are arranged on the surface of the reflective plate 72. Since the cavities 73 have an aspect ratio of 0.17 to 0.7, the infrared reflectance can be increased compared to a reflector with no cavities.

Abstract: An energy converter according to the present invention includes a heat source (radiator 1), which receives externally applied energy and raises its temperature, thereby emitting electromagnetic radiations, and a radiation cut portion (mesh 2) for cutting down infrared radiations, of which the wavelengths are longer than a predetermined wavelength. The mesh 2 is a woven or knitted mesh of metal wires. The openings of the woven or knitted mesh have an aperture size that is smaller than the predetermined wavelength.

Abstract: An energy converter according to the present invention includes a filament 11 for converting given energy into electromagnetic waves and radiating the waves, and a radiation suppressing portion for suppressing some of the electromagnetic waves (e.g., infrared rays), which have been radiated from the filament 11 and of which the wavelengths exceed a predetermined value. The radiation suppressing portion has a bundle 12 of fine wires 12a, of which the axial direction is aligned with a direction in which the electromagnetic waves propagate with their radiations suppressed.

Abstract: An incandescent lamp according to the present invention includes a radiator (such as a filament 102), which includes a plurality of cavities 120 that are arranged on at least some area of its surface in order to suppress radiations having wavelengths that are longer than a predetermined value, and a glass bulb 101 for shutting off the filament 102 from the air. The area of the filament 102 includes a layer including tungsten and carbon (such as a tungsten carbide layer), and a gas including carbon and an inert gas are enclosed within the glass bulb 101.

Abstract: An energy converter according to the present invention includes a heat source (radiator 1), which receives externally applied energy and raises its temperature, thereby emitting electromagnetic radiations, and a radiation cut portion (mesh 2) for cutting down infrared radiations, of which the wavelengths are longer than a predetermined wavelength. The mesh 2 is a woven or knitted mesh of metal wires. The openings of the woven or knitted mesh have an aperture size that is smaller than the predetermined wavelength.

Abstract: An incandescent bulb filament having a flat Light-emitting surface and high Lamp efficiency and an incandescent bulb using this filament are provided. This incandescent bulb filament is characterized in that it is a filament of ribbon shape placed on one plane, and it includes: spaced portions which are placed side by side with spaces; and connecting portions which connect the spaced portions electrically in series. Each spaced portion has a thickness that is one half the width of the spaced portion or more, and the space between at least one pair of adjacent spaced portions is less than five times the width of the spaced portion.

Abstract: An energy converter according to the present invention includes a filament 11 for converting given energy into electromagnetic waves and radiating the waves, and a radiation suppressing portion for suppressing some of the electromagnetic waves (e.g., infrared rays), which have been radiated from the filament 11 and of which the wavelengths exceed a predetermined value. The radiation suppressing portion has a bundle 12 of fine wires 12a, of which the axial direction is aligned with a direction in which the electromagnetic waves propagate with their radiations suppressed.

Abstract: An incandescent bulb filament having a flat light-emitting surface and high lamp efficiency and an incandescent bulb using this filament are provided. This incandescent bulb filament is characterized in that it is a filament of ribbon shape placed on one plane, and it includes: spaced portions which are placed side by side with spaces; and connecting portions which connect the spaced portions electrically in series. Each spaced portion has a thickness that is one half the width of the spaced portion or more, and the space between at least one pair of adjacent spaced portions is less than five times the width of the spaced portion.

Abstract: A radiator 1 according to the present invention converts heat into electromagnetic waves and then radiates the electromagnetic waves through its surface. A number of microcavities are made in at least some areas on the surface, and the surface of the microcavities 2 is covered with a layer including tungsten that is bonded to carbon.