Abstract:
A photocathode for use in vacuum electronic devices has a bandgap gradient across the thickness (or depth) of the photocathode between the emitting surface and the opposing surface. This bandgap gradient compensates for depth-dependent variations in transport energetics. When the bandgap energy EBG(z) is increased for electrons with shorter path lengths to the emitting surface and decreased for electrons with longer path lengths to the emitting surface, such that the sum of EBG(z) and the scattering energy is substantially constant or similar for electrons photoexcited at all locations within the photocathode, the energies of the emitted electrons may be more similar (have less variability), and the emittance of the electron beam may be desirably decreased. The photocathode may be formed of a III-V semiconductor such as InGaN or an oxide semiconductor such as GaInO.
Abstract:
A field emission backlight device includes: a front substrate and a rear substrate arranged in parallel and spaced apart from each other by a predetermined distance; an anode and a cathode arranged opposite to each other on a respective inner surfaces of the front and rear substrates; a fluorescent layer arranged on the anode and having a predetermined thickness; a convex portion including a plurality of convex projections arranged on an outer surface of the front substrate opposite to the anode; and electron emitters arranged on the cathode to emit electrons in response to an applied field.
Abstract:
An optical element is disclosed that includes a face plate of a cathode ray tube and a lens element facing the face plate. The optical element further includes an optical coupling material disposed between the lens element and the face plate. The optical coupling material includes particles dispersed in a host material.
Abstract:
A fluorescent display device having a pseudo half mirror formed on a rear surface a face plate thereof and exhibiting a function like a neutral density filter. The face plate is formed on a whole rear surface thereof with an aluminum film including opening portions, non-opening portions and a solid portion. The opening and non-opening portions cooperate with each other to constitute a pseudo half mirror. The pseudo half mirror has light transmittance determined depending on a ratio in area between the opening portions and the non-opening portions. Thus, the light transmittance may be set as desired by varying the area ratio.
Abstract:
This is a cathode ray tube having a panel provided with a colored layer on an outer surface of a face portion, wherein an emission luminance ratio is 75% or higher in a lowest part relative to a highest part, and a diffuse reflectance ratio is 90% or higher in a lowest part relative to a highest part in an image display area of the face portion. Due to this configuration, a cathode ray tube with a natural appearance can be obtained in which a luminance difference or a contrast difference is not perceived in the entire area of the face portion.
Abstract:
An anti-reflection film includes a transparent support and a low refractive index layer. A refractive index of the low refractive index layer is lower than a refractive index of the transparent support. The low refractive index layer contains micro voids in an amount of 3 to 50 volume % of the low refractive index layer. The anti-reflection film further has an overcoating layer provided on the low refractive index layer. The overcoating layer contains a fluorine compound. The fluorine compound is not present in the micro voids, or an amount of the fluorine compound present in the micro voids is less than 70 volume % of the micro voids.
Abstract:
An optical filter comprises a transparent support and a filter layer. The filter layer has an absorption maximum in the wavelength range of 500 to 550 nm. The filter layer further has another absorption maximum in the wavelength range of 560 to 620 nm. The optical filter has a transmittance in the range of 40 to 85% at the absorption maximum in the wavelength range of 500 to 550 nm. The optical filter further has a transmittance in the range of 0.01 to 80% at the absorption maximum in the wavelength range of 560 to 620 nm.
Abstract:
A color cathode ray tube has a vacuum enclosure including a panel unit having a fluorescent film formed on its inner face, consisting of densely arrayed three color dot trios of a fluorescent material, a shadow mask being suspended in the vicinity of the fluorescent film; a neck unit housing an electron gun for emitting three electron beams; and a funnel unit for joining the panel unit and the neck unit. The panel unit has a diagonal diameter not more than 52 cm, wherein the effective display area on the outer face of the panel unit has a diagonal radius of curvature not less than 1,000 mm, and the dot trios of the fluorescent material are horizontally arrayed in a number not less than 1,450. As a result, it is possible to provide a color cathode ray tube which has a resolution corresponding to 2M pixels, but which has no display luminance irregularity and which can be adopted for use in a desktop terminal.
Abstract:
A problem associated with field emission displays is that of `smearing` where an otherwise sharp image appears to be surrounded by a diffuse halo of light. Our investigations have suggested that this is due to spurious reflections from the surface of the gate electrode layer. To eliminate these we have deposited an anti-reflection coating on the top surface of the gate electrode layer. This prevents the reflection of light rays travelling away from the phosphor layer towards the cathode. Such rays, if their reflection were allowed, would emerge at a different spot in the display from what was intended, resulting in a false image. A method for manufacturing a field emission display based on this approach is also described.
Abstract:
In a method for manufacturing a phosphor screen of a cathode ray tube, a first photo-resist layer is coated on an inner surface of a panel of the cathode ray tube except at predetermined locations. A second photo-resist layer dispersed with pigment particles is coated on the first photo-resist layer and at the predetermined locations. The second photo-resist layer is exposed at the predetermined locations from an opposite side of the panel. The first photo-resist layer is dissolved and the second photo-resist layer is removed from the first photo-resist layer so as to form a color filter layer at the predetermined locations. A phosphor layer is formed on the color filter layer.