Abstract: A novel design for producing bandpass filters with essentially square shapes with little or no ripple in the passband zone. Filters are of the all-dielectric type that consist of multiple cavities of bandpasses with the first and last cavities consisting of four less layers than the inner cavities. The inner cavities all have the same number of layers. All of the cavities are separated from each other by quarter wave thick layers of low index material. Layers of low index material may be added between the filter and the entrance and exit mediums. Multiple half-waves are added to the outer cavity quarter-wave stacks in particular and also may be added to some of the inner cavity stacks, These sharpen the transition from low transmission to high transmission without unduly adding ripple to the high transmission zone. The thickness of the first few layers and last few layers may be altered to enhance the transmission of the filter by matching the index structure of the passband to the adjacent mediums.

Abstract: Optical device has a carrier substrate with a surface consisting of a plastic material with a predetermined index of refraction and with first mechanical and/or chemical characteristics. The surface is coated and the coating has second mechanical and/or chemical characteristics which are different from the first characteristics. The index of refraction of the coating is different from the predetermined index of refraction of the carrier substrate surface material, varying steplessly through at least a part of the coating, up to the end index of refraction and the surface of the coating.

Abstract: A broad band polarizing beam splitter includes a first prism, including an incident beam surface, and an interface surface. A second prism is also included with an interface surface. The second prism is positioned adjacent to the first prism with the interface surfaces of the first and second prisms being adjacent to each other. A coating is disposed between the two interface surfaces. The coating is made of a geometric or arithmetic progression of layer thicknesses of alternating high and low refractive indices. A ratio of high refractive index to low refractive index is 1.1 or greater.

Abstract: An optical multiplexing device spatially disburses collimated light from a fiber optic waveguide into individual wavelength bands, or multiplexes such individual wavelength bands to a common fiber optic waveguide or other destination. The optical multiplexing device has application for dense channel wavelength division multiplexing (WDM) systems for fiber optic telecommunications, as well as compact optical instrument design. Multiple wavelength light traveling in a fiber optic waveguide is separated into multiple narrow spectral bands directed to individual fiber optic carriers or detectors. An optical block has an optical port for passing the aforesaid multiple wavelength collimated light, and multiple ports arrayed in spaced relation to each other along a multiport surface of the optical block. A continuous, variable thickness, multi-cavity interference filter extends on the multiport surface of the optical block over the aforesaid multiple ports.

Abstract: A multilayer optical interference filter having a controlled degree of diffuse reflection over a desired visible wavelength range, includes alternating layers of at least one high refractive index material and at least one low refractive index material, wherein at least one layer of the alternating layers is a light scattering layer comprised of titania which diffusely reflects light over a desired visible wavelength range. The multilayer optical interference filter may be provided by a process including sequentially applying the alternating layers by chemical vapor deposition from respective precursors at temperatures effective to pyrolytically decompose the respective precursors, wherein the precursor of the light scattering layer comprised of titania is at least one branched alkoxide of titania.

Abstract: The present invention relates to a multi-layered coating for an optical part comprising at least a YF.sub.3 layer between a substrate and a dielectric material layer.

Abstract: A cathode-ray tube includes a face plate having a light transmittance of at most 50% and a reflectivity reduction film formed on the external surface of the face plate to reduce reflectivity of an external light. The reflectivity reduction film is a low refraction index layer formed by using a coating liquid obtained by dispersing and mixing magnesium fluoride superfine particles to a base coating of an alcohol solution containing a silicon alkoxide. The low refraction index layer can be laminated by a high refraction index layer formed by using a coating liquid obtained by dispersing and mixing tantalum oxide fine particles to the same base coating as that of the low refraction index layer.

Abstract: A projection cathode ray tube (CRT) includes a multilayered interference film interposed between a face plate pane and luminescent material layer. This multilayered interference film is composed of alternately superimposed of high refractive index material layers and low refractive index material layers, and the number of layers to be superimposed is four or five. By using a multilayered interference film of only four or five layers, the interference layer is not subject to cracks or film separation occurring during heat processing, due to the difference in thermal expansion coefficients between high and low refractive index material. Further, there still remains enough layers to produce a display highly improved in brightness in the direction of the normal of the face plate pane of the CRT.

Abstract: Three-layer, low color purity, anti-reflection coatings reduce the reflection of visible light rays and display a low color purity when glazings carrying such coatings are oriented at high angles of incidence with respect to a source of visible light. The reflectances are comparable and the color purity values are lower for such glazings, when compared with conventional glazings coated with 1/4-178 -174 wavelength anti-reflection coatings.

Abstract: An optical thin film filter for the spatial and spectral separation of two or more transmitting bands of radiant energy. For a two band filter the filter has a substrate substantially transparent to radiant energy in the transmitted bands. On one surface of said substrate is a multilayer interference coating that transmits both wavelength bands of interest. On the other surface of said substrate (or on the same surface) are two sets of non-overlapping butted, parallel stripes with one set being alternately interspersed with the other. The widths of said stripes are varied to provide for precisely defined regions of spatial and spectral delineation. One set of stripes is capable of transmitting one of the bands of interest and reflecting all others, while the second set of stripes is capable of transmitting at least one band different from the one band transmitted by said first set of stripes and reflecting all others.

Abstract: A multilayer film including contiguous layers of two or more diverse thermoplastic materials of differing refractive indices whereby the film retains a permanent color change as evidence of tampering or an attempt at tampering when the yield point of at least one of the diverse materials has been at least equalled by the strain associated with such tampering or with such an attempt at tampering, and where before such yield point is at least equalled the wavelength of an unsuppressed reflectance of normally incident light is not within the visible spectrum while after such yielded point is at least equalled the reflectance is retained in the visible spectrum.

Abstract: An interference film filter for use in a copying machine as mounted on an optical path of light traveling through an image-forming lens for preventing transmission of the light in a predetermined wavelength range. The filter comprises a transparent glass substrate, and interference films each consisting of a plurality of layers formed by vapor deposition on the substrate. The interference films include a film disposed centrally of the substrate, and an opposed pair or pairs side films. Each of the side films has a greater optical film thickness than the center film or a film disposed immediately inwardly.

Abstract: A color display device has groups of liquid crystal display elements controlled by respective TFTs, the groups providing respective different color outputs, e.g. red, green and blue, and being either interspersed in a single panel with individual elements associated with color filter elements or in respective separate panels illuminated by differently colored light. The TFTs are of multilayer structure having semiconductor, gate insulator and gate layers. At least one layer thickness of the TFTs is different from group to group and is selected in accordance with the color light to which they are subjected so as to reduce absorption of that light, and consequently photo-induced currents in their semiconductor layers. Significantly reduced absorption is achievable by appropriate choice for example of semiconductor and insulator layer thicknesses based on optical interference considerations. The device can be used as a projection display device.

Abstract: A multilayered, highly reflective polymeric body comprising at least two types of optical layers which is thermoformable and capable of being fabricated into films, sheets and a variety of parts while maintaining a uniform reflective appearance is provided. The reflective polymeric body includes at least first and second diverse polymeric materials having a sufficient number of layers of the first and second polymeric materials such that at least 30% of light incident on the body is reflected. A portion of the layers have optical thicknesses between 0.09 and 0.45 .mu.m, and the remaining layers have optical thicknesses of not greater than 0.09 .mu.m or not less than 0.45 .mu.m. The first and second polymeric materials differ from each other in refractive index by at least about 0.03.

Abstract: A composite optical interference filter is used in a film scanning system having a high speed CCD imager. Multiple, alternating, variable thickness layers of higher and lower index thin film oxides deposited on an optically transmissive substrate constitute the filter and enable the filter to provide color balance, notch rejection, and IR rejection all in the same device. Three such filters in a lamphouse of the film scanning system can be selected to match the system spectral response of the CCD imager and the film thereby providing equal density and color balance of the images on the film.