Abstract: An optical filter includes: a substrate; a dielectric multilayer film laid on or above at least one major surface of the substrate; and a protective layer laid on or above the dielectric multilayer film, in which the dielectric multilayer film includes a layer made of amorphous silicon and a layer differing in refractive index from the layer made of amorphous silicon, the protective layer includes a mixed film, and the mixed film includes silica, and an oxide of at least one metal selected from among tantalum, niobium, zirconium, titanium, hafnium, tungsten, tin, cerium, chromium, nickel, and vanadium.

Abstract: An induction heating device according to the present invention includes: an induction heating coil 10 with a conductor 100 wound around a predetermined axis line AL; a member 11 including at least one soft magnetic material 110, the at least one soft magnetic material 110 being disposed at or on an outer side of each of axial end portions 102 of the induction heating coil 10 in an extending direction of the axis line AL; and a heating object 2 disposed on an inner side of the induction heating coil 10 and the member 11, the heating object 2 being configured to be heatable by induction heating using a magnetic flux from the induction heating coil 10.

Abstract: An optical filter including: a substrate having a first major surface and a second major surface; a first dielectric multilayer film laid on or above the first major surface; and a second dielectric multilayer film laid on or above the second major surface, in which: each of the first dielectric multilayer film and the second dielectric multilayer film is a laminate in which one or more low refractive index films, one or more medium refractive index films, and one or more high refractive index films are laid; each of the first dielectric multilayer film and the second dielectric multilayer film includes two or more medium refractive index films; each of the first dielectric multilayer film and the second dielectric multilayer film includes a structure that the low refractive index film, the medium refractive index film, and the high refractive index film are laid in order; and the optical filter satisfies both of the spectral characteristics (i-1) and (i-2).

Abstract: An optical filter including: a substrate; and a dielectric multilayer film laid on or above at least one major surface of the substrate as an outermost layer, in which: the dielectric multilayer film is a laminate including a low refractive index film and a plurality of high refractive index films laid on each other; the dielectric multilayer film comprises four or more high refractive index films that are 15 nm or smaller in thickness; the high refractive index films have a minimum thickness of 1.5 to 5 nm; the high refractive index films have a minimum thickness of 100 nm or smaller; the high refractive index films satisfy the following spectral characteristics (i-1) and (i-2); and the optical filter satisfies all of the following spectral characteristics (ii-1) to (ii-4).

Abstract: An optical filter includes a substrate and a dielectric multilayer film laid as an outermost layer on at least one major surface of the substrate. The dielectric multilayer film includes a low-refractive index film and a high-refractive index film provided alternately. At least one film selected from the group consisting of the low-refractive index film and the high-refractive index film satisfies the following optical characteristics (i-1) and (i-2A): (i-1) an extinction coefficient k600 at a wavelength of 600 nm is 0.12 or larger; and (i-2A) a minimum extinction coefficient k1530-1570MIN in a wavelength range of 1530 to 1570 nm is 0.01 or smaller; and the optical filter satisfies the following optical characteristic (ii-1A): (ii-1A) light in a wavelength range of 400 to 680 nm is blocked and light in the wavelength range of 1530 to 1570 nm is transmitted.

Abstract: A beam splitter is an optical multilayer film obtained by sequentially stacking first to fifth layers respectively having refractive indexes of n.sub.1 to n.sub.5 and geometrical thicknesses d.sub.1 and d .sub.5 on a substrate having a refractive index n.sub.G. The refractive indexes of the substrate and the first to fifth layers satisfy any one of a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =2.02 to 2.20, n.sub.2 =2.25 to 2.38, n.sub.3 =1.44 to 1.47, n.sub.4 =2.25 to 2.38, and n.sub.5 =1.44 to 1.47, a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =1.44 to 1.47, n.sub.2 =2.25 to 2.38, n.sub.3 =1.44 to 1.47, n.sub.4 =2.25 to 2.38, and n.sub.5 =2.02 to 2.20, and a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =1.44 to 1.47, n.sub.2 =2.25 to 2.38, n.sub.3 =2.02 to 2.20, n.sub.4 =2.25 to 2.38, and n.sub.5 =1.44 to 1.47, and a geometrical thickness d.sub.i of an ith layer of the first to fifth layers satisfies relation n.sub.i d.sub.i cos (.theta..sub.i)=.lambda./4, where n.sub.

Abstract: In a high frequency ion plating device, when an evaporation substrate is intended to be rotated to form a uniform evaporated film, a variation in resistance of a contact in a rotating portion arises, making it almost impossible to provide a constant duration of high frequency discharge.A supply of a high frequency power to the substrate is effected through an auxiliary electrode such as a coil, and a dc voltage is induced in the auxiliary electrode and applied to the substrate simultaneously with a high frequency voltage. As a result of the coil the high frequency discharge is stabilized, and a stabilized supply of power is rendered possible.

Abstract: A filter medium comprising one fibrous web or a plurality of piled and integrated fibrous webs is provided. The web or webs are composed mainly of ultra-fine combustible synthetic fibers having a single fiber diameter of 0.1 to 1.5.mu.. The constituent fibers in each web are entangled with one another in various directions and satisfy the following requirements:(i) the fiber packing ratio .alpha. (%), defined by the formula: .alpha.=(.rho.'/.rho.).times.100 (.rho.=true density of the fibers, .rho.'=apparent density of the filter medium), is in the range of 20.gtoreq..alpha..gtoreq.3,(ii) the ratio S.sub.B /S.sub.A of the actually measured surface area S.sub.B (m.sup.2) of the fibers per m.sup.2 of the filter medium to the total surface area S.sub.A (m.sup.2) expressed by the formula: S.sub.A =(9000.pi..phi.w)/d (d mean single fiber denier, .phi. the means single fiber diameter (m) and W basis weight (g/m.sup.2) of the filter medium) is in the range of1>S.sub.B /S.sub.A .gtoreq.0.