Abstract: A multilayer reflective film coated substrate includes a multilayer under film comprised of Mo/Si alternately-layered films and a multilayer reflective film comprised of Mo/Si alternately-layered films for reflecting exposure light. The multilayer under film and the multilayer reflective film are formed on a substrate in this order. Given that a cycle length of the multilayer under film is d bottom (unit:nm) and a cycle length of the multilayer reflective film is d top (unit:nm), a relationship of a formula (1) is satisfied when d bottom>d top, the formula (1) given by (n+0.15)×d top?d bottom?(n+0.9)×d top where n is a natural number equal to or greater than 1.

Abstract: This invention relates to the field of thermophotovoltaic (TPV) direct energy conversion. In particular, TPV systems use filters to minimize parasitic absorption of below bandgap energy. This invention constitutes a novel combination of front surface filters to increase TPV conversion efficiency by reflecting useless below bandgap energy while transmitting a very high percentage of the useful above bandgap energy. In particular, a frequency selective surface is used in combination with an interference filter. The frequency selective surface provides high transmission of above bandgap energy and high reflection of long wavelength below bandgap energy. The interference filter maintains high transmission of above bandgap energy and provides high reflection of short wavelength below bandgap energy and a sharp transition from high transmission to high reflection.

Abstract: An imaging apparatus comprising an optical member in an optical path from a lens to an imaging device, said optical member comprising a water-repellent or water/oil-repellent coating, a first antireflection coating, an infrared-cutting glass, a lowpass filter, and an infrared-cutting coating in this order from the side of said lens.

Abstract: A pair of binoculars has lenses constituting optical filters with a transmissivity range within the wavelength range between about 650 nm and at least 800 nm and also with an additional transmissivity band within a wavelength range from about 310 nm to about 600 nm. The objects viewed with such a pair of binoculars appear as an image that is carried by a satin-finished metallic surface.

Abstract: An optical module is configured with a combination of a single-mode oscillating light source and an optical filter. In this optical module, the single-mode oscillating light source outputs a single-mode, frequency-modulated signal. Further, the optical filter converts the frequency modulation to an amplitude modulation. And, the single-mode oscillating light source and the optical filter are packaged without active alignment on the same substrate. Accordingly, it is possible to realize an optical module in a simple and low-cost configuration by packaging the single-mode oscillating light source and the optical filter by passive alignment, without active alignment, on the same substrate, and by using a simple optical filter such as a waveguide ring resonator, which converts a frequency modulation to an amplitude modulation.

Abstract: An optical element structured in accordance with the invention comprises a substrate with at least two zones with different optical functions. The coating systems in the two zones can in each case be subdivided into a zone-specific internal partial coating system and a complementary partial coating system that is common to all the zones, where the complementary partial coating system comprises at least one layer and in the zones in which the internal partial coating systems comprises at least one layer said coating system is arranged between the substrate and the complementary partial coating system.

Abstract: Data of a barometric pressure that a barometric pressure sensor outputs, and data of an air volume that an air-volume sensor outputs are input into a system control circuit. The system control circuit is provided with a table storing portion. In the table storing portion, a control table is stored. The control table is formed of a plus supplied-voltage value to fan power set by a barometric pressure value and an air-volume value, and a warning instruction. In a case that the warning instruction is selected based on the barometric pressure value and the air-volume value, the system control circuit turns on a warning-use LED so as to inform a user that a filter is clogged.

Abstract: Various embodiments of the invention relate to methods and systems for generating the color white in displays created from interferometric modulators and more specifically, to the generation of the color white through the use of reflected light at two wavelengths. In one embodiment, a display device displays the color white. The color white is generated by reflecting light from two pluralities of interferometric modulator types. The first modulator type reflects colored light at a specific wavelength. The second modulator type reflects colored light selected to be at a wavelength complementary to the first. The combined light reflected from the two types appears white in the display.

Abstract: A projection optical system having a multilayered film mirror arranged to provide an approximately uniform reflectance throughout a predetermined light incidence angle range to thereby assure a desired optical performance. A projection exposure apparatus having such a projection optical system, and a device manufacturing method using such an exposure apparatus. A non-periodic film is used in a reflection multilayered film upon a mirror having a largest light incidence angle range or a mirror having a largest average of light incidence angle, and this effectively reduces a pupil transmittance distribution in the projection optical system.

Abstract: In a plasma display apparatus of the preset invention, an external light shielding sheet configured to shield externally incident light to the greatest extent possible is disposed at the front, thus effectively implementing a black image and improving the bright and dark room contrast. Furthermore, pattern units of the external light shielding sheet are formed using a conductivity material. Accordingly, there is an advantage in that EMI emitted from a panel can be prevented from being radiated to the outside.

Abstract: An exemplary optical filter includes a substrate, a plurality of contiguous identical lower filter cavities formed on the substrate, and a plurality of contiguous upper filter cavities formed on the lower filter cavities. Each of the lower filter cavities includes two high refractive index layers and one low refractive index layer sandwiched between the high refractive index layers. Each of the upper filter cavities includes two low refractive index layers and one high refractive index layer sandwiched between the low refractive index layers. The plurality of upper filter cavities includes a first filter cavity, a plurality of second filter cavities, a third filter cavity, and a plurality of fourth filter cavities.

Abstract: An optical element which includes an optical block having a cavity part formed on an optical path and an inclined face formed in an internal face of the cavity part at a prescribed inclining angle with respect to a traveling direction of light. Multilayer films of the same structure are formed at least on the internal face of the cavity part and on an interface between a light incident end and/or emission end of the optical block and outside. The multilayer film formed on the incline face in the internal face of the cavity part has at least a wavelength selecting function for light to be used.

Abstract: A combination of filters for filtering selected wavelengths of electromagnetic radiation is provided on a transparent substrate such as a plastic film or glazing of a window. The combination of filters prevents or attenuates the passage of wavelengths through the substrate into a building, where the passage of the wavelengths into the building could adversely affect people or machinery within the building. The combination of filters is useful improve wireless networks performance by blocking or attenuating undesired electromagnetic interference, and radio frequency interference.

Abstract: The invention relates to wavelength-selective optical filters for allowing light of a narrow optical spectral band, centered around a wavelength (?c) to pass through them, while reflecting the wavelengths lying outside this band. According to the invention, the transfer function (T1,2(?)) of the component is defined by multiplying two transfer functions of spectrally offset Fabry-Perot filters.

Abstract: A CWDM filter of the present invention comprises a substrate; a first portion formed on the substrate having at least two first stacking structures; a second portion superposed on the first portion including at least two second stacking structures; and a first matching layer sandwiched between the first and second portions. Each of the first stacking structures of the first portion has a Fabry-Perot cavity and a first coupling layer which are stacked over each other in turn from the substrate. Each second stacking structure has a (HnLH) structure and a second coupling layer, wherein n represents a positive integer greater than 1, L represents a low index layer with a thickness of ?o/4, H represents a high index layer with a thickness of ?o/4, and ?o is the center wavelength of said noise.

Abstract: A combination of filters for filtering selected wavelengths of electromagnetic radiation is provided on a transparent substrate such as a plastic film or glazing of a window. The combination of filters prevents or attenuates the passage of wavelengths through the substrate which would pose a security risk. The combination of filters is useful to prevent unauthorized data collection and information exchange from or within buildings or otherwise prevent such unauthorized data collection and information exchange from, for example, computer monitors or screens, personal digital assistance, and local area networks. The substrate with the combination of filters may be in the form of a bag or a tent.

Abstract: Provided is a Fabry-Perot type wavelength tunable optical filter, comprising a first mirror; a second mirror located over the first mirror; a driving body located over the first mirror, and having both ends fixed to the first mirror through a spacer; a plurality of electrodes, each formed on both ends of the driving body; a rod structure connecting a center of the driving body and the second mirror; a plurality of fixing means, each fixed to the first mirror at both sides of the rod structure through the spacer; and a plurality of elastic bodies connecting the rod structure with the plurality of fixing means and acting as a rotational axis. And the mirror is driven by the rod structure acting as a lever that has an elastic body as a rotational axis, when warping is generated by electro-thermal expansion, electromagnetic force or external force. Thereby the mirror can be driven in the larger wavelength tunable range and the low power consumption.

Abstract: An optical element has a structure in that a first mirror stack layer is formed on a substrate. A first transparent conductive film, a conductive buffer layer, a spacer layer having a primary or secondary electrooptic effect, a conductive buffer layer and a second transparent conductive film are stacked thereon in succession; and a second mirror stack layer is further formed thereon. A voltage is applied between the first and second transparent conductive films. The applied voltage change the refractive index of the spacer, changes a wavelength to be transmitted through or reflected from the layer.

Abstract: A combination of filters for filtering selected wavelengths of electromagnetic radiation is provided on a transparent substrate such as a plastic film or glazing of a window. The combination of filters prevents or attenuates the passage of wavelengths through the substrate which would pose a security risk. The combination of filters is useful to prevent unauthorized data collection and information exchange from or within buildings or otherwise prevent such unauthorized data collection and information exchange from, for example, computer monitors or screens, personal digital assistance, and local area networks. The substrate with the combination of filters may be in the form of a bag or a tent.

Abstract: A reflector for extreme ultraviolet light, its manufacture method, a phase shift mask, an exposure apparatus and a semiconductor manufacture method, capable of making the wavelength dependency of a reflectance via a plurality of reflection surfaces be coincident with an center wavelength of exposure light and retaining a sufficient energy reaching a subject to be exposed. The reflector for exposure light to be used for exposure of a subject to be exposed in a lithography process of manufacturing a semiconductor device is configured to have a multi-layer film structure made by repetitively stacking a plurality of layers in the same order. The periodical length of the repetitive stack unit of the multi-layer film structure is set in such a manner that the center of full width at half maximum of the reflectance via a predetermined number of reflectors becomes coincident with the center wavelength of extreme ultraviolet light to be reflected (S102).

Abstract: This invention relates to the field of thermophotovoltaic (TPV) direct energy conversion. In particular, TPV systems use filters to minimize parasitic absorption of below bandgap energy. This invention constitutes a novel combination of front surface filters to increase TPV conversion efficiency by reflecting useless below bandgap energy while transmitting a very high percentage of the useful above bandgap energy. In particular, a frequency selective surface is used in combination with an interference filter. The frequency selective surface provides high transmission of above bandgap energy and high reflection of long wavelength below bandgap energy. The interference filter maintains high transmission of above bandgap energy and provides high reflection of short wavelength below bandgap energy and a sharp transition from high transmission to high reflection.

Abstract: A wavelength tunable filter capable of being driven such that reflecting mirrors move more distant as well as closer by using the principle that a direction of the electromagnetic forces changes depending on the direction of the current flowing perpendicular to the external magnetic field. According to the wavelength tunable filter of the present invention, when it is necessary to have the wavelength tuning range and mechanical structure similar to the conventional wavelength tunable filter driven in only one direction, it is possible to lower the maximum force needed to drive the filter to a half, and reduce a probability that a pull-in phenomenon occurs. On the other hand, it is possible to reduce a wavelength change time of the element by increasing a resonant frequency when the same wavelength tuning ranges are implemented by using the same maximum driving forces.

Abstract: High performance optical edge and laser-line filters and methods of making the same are disclosed. The optical edge filters have an edge steepness greater than about 0.8% as measured by dividing (a) the edge width from the 50% transmission wavelength to the optical density 6 (“OD6”) wavelength by (b) the 50% transmission wavelength. The optical edge filters also have an average transmission above about 95%. The laser-line filters have an extremely high transmission in the passband (greater than 90%), an extremely narrow transmission bandwidth, and achieve blocking with an optical density (OD) greater than 5 at wavelengths that differ from the laser wavelength by less than 1% of the laser wavelength. The methods for making such filters accurately determine when deposition of each layer of the filter should terminate.

Abstract: An optical cavity is combined with a MUX or a de-MUX device having substantially the same free-spectral range in order to enhance the bandwidth of the device. The optical cavity can be tuned to shift the frequencies of maximum insertion loss to match the center frequency of each channel. The reflectivities of the reflective surfaces of the cavity are judiciously selected to produce the insertion-loss spectrum needed to optimize the desired result. Multiple cavities can be used in series to refine the shape of the pass-band spectrum. A frequency window is used to fine tune the free-spectral range of the cavity and to shift the peaks of its insertion-loss spectrum to the desired frequencies. Inner and outer cavity surfaces are oriented to eliminate interference from secondary reflections.

Abstract: The present invention provides an optical apparatus comprising an optical gain correction filter having a multilayer film structure formed by stacking a plurality of thin films with different diffractive indexes on a light transmitting board, wherein when the light with the wavelength ? enters at the incident angle ?, the transmissivity is assumed to be T1 (?, ?) (0?T1 (?, ?)?1), and the thickness and stacking state of each thin film of the optical gain correction filter are adjusted to increase the transmissivity T1 (?0, ?) when the incident angle ? increases close to the predetermined maximum incident angle ?max with respect to the incident light with the wavelength ?0. The optical apparatus is applied to a bar code reader.

Abstract: The invention provides a tunable filter that can minimize adjacent channel cross talk despite an increase of a number of available wavelengths and quickly switch a wavelength to be used, and manufacturing method thereof, and also an optical switching device comprising such tunable filter. In a tunable filter having a Fabry-Perot etalon structure, not less than two cavity gaps 114 to 116 are provided and separation between the cavity gaps is controlled by any of electrostatic drive, electromagnetic drive or piezoelectric drive. In this case, the cavity gaps can be formed through the steps of forming a sacrificial layer in advance where a cavity gap is to be formed; forming a plurality of optical multilayer films 100 to 103; and removing the sacrificial layer by etching. Substrates 107 and 109 are combined through a supporting column 108.

Abstract: A protective optical filter assembly for thin film filters having two transparent substrates facing one another and separated by a resilient element, a sealed region is formed between the transparent substrates by applying a compressive force that compresses the resilient element. The thin film filter may be contained within a carrier. The compressive force may be generated by one or more interference-fit aperture rings or threaded apertures ring, a given aperture ring may be opposed by another such aperture ring or a fixed stop. Alternatively a snap fit carrier may be used to generate the compressive force. The sealed region may have a gas having a positive pressure or a liquid.

Abstract: A complementary comb filter pair, and method for making same, are described, wherein each comb filter element of the complementary pair can be fabricated during the same deposition run. The complementary comb filter is masked so as to retard the thin film growth of the coating, for example, a dielectric material, so as to produce a desired wavelength transmission profile.

Abstract: A multilayer mirror (1), in particular a multilayer dispersive mirror, comprising several individual layers (2, 3) of different properities applied to a substrate (4; 14) and following each other via parallel, plane interfaces (6), and a plane front face (5; 5?) on the side of beam impact which is inclined relative to the interfaces (6) between the individual layers (2, 3).

Abstract: Multi-stage, all-pass optical filters used to make low-loss, multi-channel dispersion compensation modules are disclosed. The all-pass optical filters can be ring resonators in waveguides, Gires-Tournois Interferometers (GTIs) in free space form, and the like. The coupling constants and circulating path lengths may also be distinctively varied in each of the series of GTIs, tuning the net dispersion spectrum of the GTI set, such that the sum of the dispersions from the series of GTI's can provide a system with greater bandwidth than the same number of identical GTIs. The local dispersion slope can also be tuned in this manner. Multi-cavity GTIs can also be formed with similar performance enhancing properties.

Abstract: An exemplary embodiment of the invention is an optical filter including a mirror including a plurality of first dielectric layers having a first index of refraction and a plurality of second dielectric layers having a second index of refraction. A plurality of the first dielectric layers have an integer quarter wave optical thickness and at least one of the first dielectric layers has a non-integer quarter wave optical thickness. A plurality of the second dielectric layers have an integer quarter wave optical thickness and at least one of the second dielectric layers has a non-integer quarter wave optical thickness. In an exemplary embodiment, the non-integer quarter wave optical thickness first layer and the non-integer quarter wave optical thickness second layer are determined so as to enhance transmission at a predetermined wavelength.

Abstract: The invention provides a tunable filter that can minimize adjacent channel cross talk despite an increase of a number of available wavelengths and quickly switch a wavelength to be used, and manufacturing method thereof, and also an optical switching device comprising such tunable filter. In a tunable filter having a Fabry-Perot etalon structure, not less than two cavity gaps 114 to 116 are provided and separation between the cavity gaps is controlled by any of electrostatic drive, electromagnetic drive or piezoelectric drive. In this case, the cavity gaps can be formed through the steps of forming a sacrificial layer in advance where a cavity gap is to be formed; forming a plurality of optical multilayer films 100 to 103; and removing the sacrificial layer by etching. Substrates 107 and 109 are combined through a supporting column 108.

Abstract: Multilayer polymeric films and other optical bodies are provided which is useful in making colored mirrors and polarizers. The films are characterized by a change in color as a function of viewing angle.

Abstract: A coated optical lens includes a lens element and a coating on the surface of the lens element. The coating exhibits a substantially balanced reflectance from the center to a radius proximate the edge of the lens element. The term “substantially balanced reflectance” means that where the thickness of the coating varies across the surface of the lens, the lightness, hue and chroma of the reflectance vary in a balanced manner such that variations in visual appearance are either imperceptible or generally acceptable to an observer. For example, variations in chromatic attributes, such as hue, from the center to the edge of the lens may be balanced by a reduction in lightness from the center to the edge. Preferably, the lens element includes a surface of high curvature upon which the balanced reflectance coating is deposited.

Abstract: A narrow bandpass optical filter for use in a WDM communication minimizes the system bit rate error by providing a sufficiently broad passband with respect to the data transfer rate yet has a low group delay across the passband. The passband shape is optimized to have a single maximum in the center of the passband and continuously decreasing transmission there from so as to minimize dispersion in GD across the passband.

Abstract: The optical system includes a plurality of light modulators, one or more combining filters, and an optical relay system including a filter. Each light modulator modulates a corresponding incident light beam. The one or more combining filters superimpose the modulated light beams from each of the plurality of light modulators. The optical relay system filters the superimposed light and relays the filtered light to an image plane.

Abstract: The present invention has an object to provide a manufacturing method of readily realizing an optical filter having a flat transmission characteristic and a superior cutoff characteristic relative to adjacent bands. To this end, with the manufacturing method of the present invention, a band-pass filter consisting of a dielectric multilayer coating is formed on one plane of a transparent substrate, and an antireflection coating is formed on the other plane of the substrate. The substrate is then divided into a plurality of segments, and adjacent two segments are selected and adhered to each other by a transparent adhesive with band-pass filter surfaces of these segments facing to each other, while interposing a glass spacer between the band-pass filter surfaces, to thereby obtain an optical filter.

Abstract: Optical filters (1) designed in pairs, which are essentially colourless in their individual general appearance designed to take on a strong coloration when viewed together in transmission, said filters being particularly, useful for identification of counterfeit articles. The optical filters (1) utilize resonantly-coupled Fabry-Perot etalons of, an asymmetric design. The filters (1) are configured such that one of the Fabry-Perot cavities within the filter incorporates an additional multiple quarter wave thickness layer (20), said additional layer having a contrasting refractive index to that of the cavity spacer.

Abstract: A Fabry-Perot filter has at least two mirror structures defining a resonant cavity. This filter is tunable by modulating an optical distance between the mirror structures. To accommodate a wide bandwidth of operation or accommodate two spectral bands, the mirror structures are made from two stacked, single-band mirrors. In more detail, the mirror structures comprise a substrate; a first mirror is deposited on the substrate, with an index matching coating between the substrate and the first mirror. The second mirror is stacked on the first mirror. The mirrors are symmetric relative to each other, such that the index of a first mirror in the second spectral band has an effective index of about one. In contrast, the second mirror has an effective index of about one in the first spectral band.

Abstract: Thin-film interference filters are constructed with a generalized pattern of layers differing in both thickness and refractive index to produce spectral responses appropriate for adjusting optical power among a plurality of different wavelength channels. Each of the layers is composed of unit sub-layers having thicknesses equal to a quarter-wavelength thickness of a monitoring beam. Interference fluctuations of the monitoring beam associated with the deposition of the unit sub-layers enable a gain-flattening filter to achieve greater manufacturing accuracy by exploiting self-correcting effects of “turning point monitoring” techniques.

Abstract: An original light source or a light source adopting a method to modulate the waveform intensity with a stack of gain-flattening filters includes the following procedures: preparing a stack of gain-flattening filters made of more than two or three aligned single filters, each is made by stacking on a substrate or on both sides of a substrate with several layers of optical films having different refractive indexes; followed by modulating the waveform intensity with a stack of gain-flattening filters installed at the emitting end of the original light source or light source, wherein the angle of each single filter can be adjusted to change the spectrum of a whole set of filters so that the waveform intensity of the original light source or light source is changeable when the emitted original light source or light source is modulated with a stack of gain-flattening filters.

Abstract: An array of detectors of electromagnetic radiation is positioned behind a pair of “grade” or “variable” filters and are inclined with respect to each other so that the detectors view a range of center wavelengths of varying bandwidths.

Abstract: Laminated adhesive-backed color-correction and light-diffusion filters are comprised of a gel layer having a desired light wavelength characteristic, one face of which is affixed by means of an optically transparent adhesive to an optically transparent supporting substrate. The other side of the supporting substrate is fixed, by means of an optically transparent adhesive layer, to an optically transparent peelable protective film. This process is done in such a way that no distortion, irregularities, or imperfections are detectable on any surface, allowing clear visual inspection and full color-corrective quality. Moreover, more than one such filter can be combined to achieve unique results.

Abstract: Disclosed are articles having a color shifting film and indicia located behind the color shifting film. The indicia include at least a first and second colored portion, the first portion including a first fluorescent colorant. The second colored portion is non-fluorescent but has a color similar to that of the first portion to enhance concealment of the indicia under certain viewing conditions. At least one of the colored portions is patterned.

Abstract: A narrow bandpass optical filter for use in a WDM communication minimizes the system bit rate error by providing a sufficiently broad passband with respect to the data transfer rate yet has a low group delay across the passband. The passband shape is optimized to have a single maximum in the center of the passband and continuously decreasing transmission there from so as to minimize dispersion in GD across the passband.

Abstract: A diffraction optical element comprises a substrate, a diffraction grating formed on the substrate with a material with low ultraviolet resistance and an ultraviolet screening means arranged on the substrate at a position closer to the incident light receiving side of the optical element relative to the diffraction grating. The ultraviolet screening means comprises a dielectric multilayer film and is formed on the other side of the substrate than the side carrying the diffraction grating. Alternatively, the ultraviolet screening means may be provided as a separate member from a diffraction optical element and arranged at a position closer to the incident light receiving side of the diffraction optical element in an optical system.

Abstract: A wavelength tunable optical filter 14 and a method of making the same. The optical filter 14 comprising two back-to-back Fabry-Perot optical cavities 30 & 40 comprising a fixed mirror 31 common to both cavities with parallel displaceable mirrors 32 & 42 located one on each side of the fixed mirror 31 to adjust the overall known length of the respective cavities. One optical cavity may have greater length than the other optical cavity.

Abstract: An optical body comprising (a) a dielectric multilayer film having a reflecting band positioned to reflect infrared radiation of at least one polarization at an incident angle normal to the film, the reflecting band having a short wavelength bandedge &lgr;a0 and long wavelength bandedge &lgr;b0 at a normal incident angle, and a short wavelength bandedge &lgr;a&thgr; and long wavelength bandedge &lgr;b&thgr; at a maximum usage angle &thgr;, wherein &lgr;a&thgr; is less than &lgr;a0 and &lgr;a0 is selectively positioned at a wavelength greater than about 700 nm; and (b) at least one component which at least partially absorbs or reflects radiation in the wavelength region between &lgr;a&thgr; and &lgr;a0 at a normal angle of incidence.

Abstract: The present invention provides a device in the form of a filter which is useable in conjunction with a plasma display panel, which is applied to the front face of a display, and which functions to reduce reflection after assembly to acceptable levels, to increase contrast enhancement ratios, to reduce EMI emissions to levels which comply with consumer safety or other governmental or other regulations or standards and to reduce infrared transmission in the 800 nm-1000 nm range to a level which does not interfere with IR remote control operation. The present invention also relates to a method of making such a plasma display panel filter and device.

Abstract: The present invention has an object to provide a manufacturing method of readily realizing an optical filter having a flat transmission characteristic and a superior cutoff characteristic relative to adjacent bands. To this end, with the manufacturing method of the present invention, a bandpass filter consisting of a dielectric multilayer coating is formed on one plane of a transparent substrate, and an antireflection coating is formed on the other plane of the substrate. The substrate is then divided into a plurality of segments, and adjacent two segments are selected and adhered to each other by a transparent adhesive with band-pass filter surfaces of these segments facing to each other, while interposing a glass spacer between the band-pass filter surfaces, to thereby obtain an optical filter.