Abstract: An antireflection film includes a first light-transmitting thin film formed on a substrate, and a second light-transmitting thin film formed on the first light-transmitting thin film. The first light-transmitting thin film contains a coloring material, and the antireflection film satisfies.lambda.t-50 nm<.lambda.r<.lambda.t+70 nmwhere .lambda.r is the wavelength at which a spectral reflectance in a visible region is minimized, and .lambda.t is the wavelength at which a spectral transmittance in the visible region is minimized.

Abstract: A jacket having a pair of small helical gears is spline-fitted around a splined shaft. Since the small helical gears have an adverse helix angle to each other, the jacket moves along the spline shaft in the axial direction so as to distribute an equal torque to both small helical gears. The splited torque is transmitted to a pair of drive shafts each of which drives the main rotor of a helicopter through a combination of gear and pinion. The drive shafts are fixed axially and therefore helical gears or double-helical gears can be used in the combination of gear and pinion.

Abstract: A coating solution composition for forming a glass gel thin film, contains at least one material selected from the group consisting of a metal alkoxide and a polycondensate of the metal alkoxide, a coloring material, an alcohol solvent, and a dispersant having an adsorption material for the coloring material, soluble in the alcohol solvent, and having miscibility with the metal alkoxide, wherein the coloring material has an average particle size of 3 nm to 300 nm. A glass gel thin film obtained by sintering this composition at a temperature of 100.degree. to 300.degree. C. is excellent in water resistance, durability and has a high strength.

Abstract: A coating solution composition for forming a glass gel thin film, contains at least one material selected from the group consisting of a metal alkoxide and a polycondensate of the metal alkoxide, a coloring material, an alcohol solvent, and a dispersant having an adsorption material for the coloring material, soluble in the alcohol solvent, and having miscibility with the metal alkoxide, wherein the coloring material has an average particle size of 3 nm to 300 nm. A glass gel thin film obtained by sintering this composition at a temperature of 100.degree. to 300.degree. C. is excellent in water resistance, durability and has a high strength.

Abstract: The present invention is directed to an antireflection film having a multilayer structure in which an antireflection multilayer film including at least two thin films is formed on a substrate, wherein at least one of the thin films contains a coloring agent. The antireflection multi-layer film absorbs light of an entire range of wavelength of 400-700 nm, and the reflectance of the antireflection multi-layer film with regard to the wavelength, light of which this antireflection multi-layer film can absorb, is smaller than the reflectance of the substrate. The antireflection film can be applied to a cathode ray tube or a light-transmitting display substrate of a display apparatus such as a liquid crystal display apparatus for the purpose of effectively avoiding reflection of external light.

Abstract: A display device including a display screen having an optical film provided thereon. The optical film is a porous thin film made of fine magnesium fluoride particles and a binder containing a condensate of a silane compound having a fluoroalkyl group, a co-condensate of the silane compound and silicon, or a co-condensate of the silane compound and a metal oxide compound. The combination of the specific binder and fine magnesium fluoride particles permits forming a porous optical film having a surprisingly high mechanical strength, excellent resistance to humidity and reduced external light reflection from the display plane.

Abstract: A cathode ray tube has a vacuum envelope which includes a faceplate, an optical filter formed on the faceplate, the optical filter including mainly of SiO.sub.2 and containing a coloring material, and a phosphor layer formed on the inner surface of the faceplate. The optical filter includes silicon having a fluorine-containing group and a siloxane bond at least on the surface thereof, and a maximum light absorption wavelength in a range of 400 to 650 nm is in a region of 575.+-.20 nm, and where the transmissivity for the wavelength of 450 nm is T.sub.450, that for 530 nm is T.sub.530, that for 550 nm is T.sub.550, that for 630 nm is T.sub.630, and that for the maximum absorption wavelength is Tmin, the following relationship is established:Tmin.ltoreq.T.sub.550 .ltoreq.T.sub.530,1.ltoreq.T.sub.450 /T.sub.539 .ltoreq.2,1.ltoreq.T.sub.630 /T.sub.530 .ltoreq.2,0.7.ltoreq.T.sub.450 /T.sub.630 .ltoreq.1.43.

Abstract: A display device comprising a display screen, and an optical film formed on the display screen and having a porous lower layer mainly consisting of TiO.sub.2 and having a porosity of 30% to 75% and an average pore size of 10 nm or less and an upper layer stacked on the lower layer and essentially consisting of a silicon compound having a fluorine-containing group and a siloxane bond. In this display device, the optical film can be easily formed and has a satisfactory anti-reflection effect and satisfactory strength.

Abstract: A color picture tube comprising an envelope including a front panel, a phosphor screen formed in the inner surface of the front panel, and an electron gun arranged in the envelope. The phosphor screen includes a light absorbing layer having a plurality of holes and phosphor layers formed in the holes so as to partially overlap the light absorbing layer. The transmittance T of the light absorbing layer, the ratio a of the area of a light emitting region in a portion where the light absorbing layer overlaps the phosphor layers to the area of the phosphor screen, the ratio b of the area of the light absorbing layer to the area of the phosphor screen, and the ratio r of the light emitting region in the holes to the area of the holes satisfy the following relational expression: 1/T.gtoreq.1/2{(rb/a)-[a/(1-b)r]}.

Abstract: A color cathode ray tube includes an envelope having, a faceplate, light filtering device provided on an outer surface of the faceplate, and a phosphor screen formed on an inner surface of the faceplate. The phosphor screen is composed of red, blue, and green emitting phosphors. The red emitting phosphor is primarily a Y.sub.2 O.sub.3 :Eu phosphor with an Eu activation amount between 3.0 mol % and 9.0 mol % inclusive with respect to a Y.sub.2 O.sub.3 amount as a base material. The light filtering device is provided in front of the faceplate for selectively transmitting light having a maximum absorption wavelength of 575.+-.20 nm in a wavelength range from 400 nm to 650 nm, and satisfies the following relationship: T.sub.min .ltoreq.T.sub.550 .ltoreq.T.sub.530, 1.ltoreq.T.sub.450 /T.sub.530 .ltoreq.2, 1.ltoreq.T.sub.615 /T.sub.530 .ltoreq.2, 0.7.ltoreq.T.sub.450 /T.sub.615 .ltoreq.1.43, T.sub.615 /T.sub.580-600 .gtoreq.1.1, wherein T.sub.450, T.sub.530, T.sub.505, T.sub.615, T.sub.min and T.sub.

Abstract: A color picture tube includes a vacuum envelope having a faceplate, a phosphor screen formed to include semitransparent black light-absorption layers coated on a first region of the faceplate in stripes or in a matrix, and phosphor layers of blue, red and green emitting phosphors coated on a second region of the faceplate in stripes or in dots, and an electron gun, arranged within the vacuum envelope, for emitting and focusing electron beams. End portions of the phosphor layers extend over the black light-absorption layers, thereby forming overlapped portions. Gaps are provided between the phosphor layers and over the black light-absorption layers, thereby forming light-absorption sections on which no phosphor layer is provided.

Abstract: a cathode ray tube comprises an envelope including a faceplate with an inner and outer surface and an antistatic layer covering the outer surface of the faceplate for discharging static charges accumulating in the faceplate. The antistatic layer is formed by using a solution containing an alcoholate of silicon as main constituent. The antistatic layer contains a stabilizing substance for maintaining antistatic characteristics. The antistatic layer also has light filtering characteristics when the layer contains xanthene dye as filtering substance.

Abstract: A color filter comprising a vitreous material including at least one kind of organic compound having visible light absorbing properties, and at least one metallic compound selected from the group consisting of a Ni compound and a Co compound. A given dye can be used in the color filter of this invention as the organic compound. Thus, the hue of the color filter is freely selectable. In addition, high light resistance can be attained by sealing the organic compound in the vitreous material in the presence of the metal compound.

Abstract: A cathode ray tube has an envelope including a faceplate with a sidewall portion and a neck receiving an electron gun emitting at least one electron beam. The faceplate is coated with a phosphor layer for emitting a visible light by bombardment of the electron beam on its inner surface and is covered with an antistatic film. To prevent accumulation of electrostatic charges, the antistatic film is electrically connected to a metal tension band wound around the sidewall portion by a connecting element. The connecting element is conductive oxide layer which essentially consists of a conductive substance and a binder consisting at least amorphous silicon oxide or silicon hydroxide.

Abstract: A method of and apparatus for forming a thin film having a smooth surface and a uniform film thickness such as an antistatic or antireflection film on the outer surface of a display screen of a cathode ray tube, includes the steps of applying a film formation material solution containing a volatile solvent on the outer surface of the display screen of the cathode ray tube to form a solution film, rotating the cathode ray tube about a tube axis thereof to obtain an uniform film thickness of the solution film, and causing a portion of the solution film applied in and near the center of the outer surface of the display screen to dry while the cathode ray tube is being rotated.

Abstract: A cathode ray tube according to the present invention has a sufficient antistatic property which can be obtained by forming a glass film containing SiO.sub.2 or P.sub.2 O.sub.5 as a main component and a hygroscopic metal salt on the outer surface of its front panel.

Abstract: According to the invention, an antistatic/anti-reflecting film of high adhesive strength can be formed easily by forming an SiO.sub.2 film on a cathode-ray tube faceplate by means of a condensation reaction of polyalkyl siloxane consisting essentially of condensed alkyl silicates. As a result, the sintering conditions for forming an antistatic/anti-reflecting film can be set adequately. The antistatic effect can be further enhanced, reflection of the external light can be decreased, and workability can be greatly improved.

Abstract: In a cathode ray tube, a single layer for prevention of a reflection of light rays is formed on a face plate having a non-spherical outer surface. The thickness of the layer is continuously decreased from the center region toward the peripheral regions of the face plate.

Abstract: This invention provides a cathode-ray tube having an antistatic film formed mainly by metal oxide and containing particles of at least one metal selected from the group consisting of Pd, Sn, Pt, Ag and Au, the particles having an average particle size of 0.01 micron at most. The film can be easily formed from a solution, thus, reducing the cost.

Abstract: In a cathode ray tube with a phosphor screen containing a Zn type green emitting phosphor, e.g. ZnS, ZnCdS and Zn.sub.2 SiO.sub.4, the surface of the phosphor particle includes a surface area of (Co,Zn)O. The surface area is green colored to operate as a filter against incident light from outside the tube and reduces background brightness of picture images caused by excitation of scattering electrons. Thus, the contrast of the picture images rises. The contrast is further increased by Ni doped.