Abstract: Provided are a lens device, an imaging apparatus, and a filter unit capable of suppressing occurrence of ghosts and flares. The lens device includes a first optical filter and a second optical filter in order from an object side in an optical path. The first optical filter is composed of an optical filter (for example, a band-pass filter) that has a light transmission band in a specific wavelength region. The second optical filter is composed of an optical filter (band-stop filter) that has a light absorption band in a wavelength region which is different from the light transmission band of the first optical filter.

Abstract: An imaging method of imaging a subject through a multispectral camera including a processor, includes: causing the processor to perform: a data acquisition step of acquiring first spectral data of a first subject, second spectral data of a second subject, and third spectral data of a third subject; a wavelength selection step of selecting a plurality of wavelengths from a wavelength region of the acquired first to third spectral data, the wavelength selection step being for determining, as a computational amount, a difference or a ratio between feature amounts of two pieces of spectral data, from among the first spectral data, the second spectral data, and the third spectral data, and obtaining computational amounts to select the plurality of wavelengths; and an imaging step of imaging a subject including at least one of the first subject, the second subject, or the third subject at the plurality of wavelengths.

Abstract: A lens device includes an imaging optical system and an optical member. The optical member is disposed near a pupil of the imaging optical system in a state where an optical axis of the optical member coincides with an optical axis of the imaging optical system. The optical member includes a frame that includes a plurality of aperture regions, a plurality of optical filters that are disposed in at least one of the plurality of aperture regions and include two or more optical filters transmitting light having at least some wavelength ranges different from each other, and a plurality of polarizing filters that are disposed in at least one of the plurality of aperture regions and have different polarization directions. The lens barrel has a slit, and the optical member is insertable into and removable from the imaging optical system through the slit.

Abstract: A method of manufacturing a photo-rechargeable storage battery includes cutting a filter paper of glass fiber as a base material in a preselected shape to provide a cut filter paper; washing the cut filter paper; coating a polypyrrole film on at least a portion of a surface of the cut filter paper; and carrying a gel of poly-tungustic acid having a form of clusters on at least a portion of the glass fiber coated with the polypyrrole film thereby forming a composite electrode on the filter paper.

Abstract: A high-temperature YBa.sub.2 Cu.sub.3 O.sub.x superconducting sintered body is produced through wet grain-coating process in which starting grains are soaked in SnI.sub.4 solution, pressed after the removal of solvent and then sintered at a given temperature, and has a critical current density of at least 500 A/cm.sup.2 at 77 K.

Abstract: A composite electrode for a photo-rechargeable storage battery includes a filter paper of glass fiber as a base material; a polypyrrole film coated on a surface of the filter paper to provide a conductive polymer; and a gel of polytungustic acid provided on the polypyrrole film in the form of a cluster to provide a photo-catalytic property. The polypyrrole film may be vapor phase polymerized and coated onto a surface of the filter paper and the gel of polytungustic acid may be vapor phase coated onto the polypyrrole film in the form of a cluster. Thus, all electrode manufacturing steps can be carried out in the vapor phase so that manufacturing of such an electrode having a very large specific surface area is practical and large electrode areas may be manufactured.

Abstract: A method for producing high-temperature superconducting ceramic material through mechanical orientation including mixing starting materials in powdered form in proportions effective to produce a high-temperature superconducting oxide ceramic having anisotropic crystal grains and shaping the mixture. Next, the shaped mixture is calcined at a temperature ranging from 600.degree. to 900.degree. C. and fired at a temperature higher than 1,000.degree. C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains. According to the invention, the superconductive oxide ceramic is then pulverized into particles having either a plate-like form or a needle-like form based on the anisotropic form of the crystal grains. Particles of a selected size are placed into a vessel and vibrated with an acoustic vibrator means under conditions effective to cause the pulverized particles to turn toward a common preferred orientation to provide oriented particles.