Abstract: An optical communication system for transmitting multiple optical beams, each at a different wavelength is disclosed. The optical communication system includes a laser array having multiple laser transmitters transmitting multiple optical beams, each at a different wavelength. The optical communication system further includes a diffraction grating optically coupled to the laser array, the diffraction grating diffracting each of the optical beams at a substantially equal diffraction angle to form a combined optical beam. The combined beam is then focused into an optical communication media.

Abstract: A VIPA plate having a configuration where a translucent reflection film and a total reflection film are respectively arranged on one side and the other side of a transparent parallel plate can be used as a wavelength dispersion compensator by using a special mirror and a lens. However, the transparency characteristic of the wavelength dispersion compensator using such a VIPA plate is a periodical characteristic which is asymmetric with a central wavelength in a wavelength regime. Accordingly, not parallel light but converged or diverged light having angular dispersion is input to an etalon plate, so that a filter whose transparency characteristic is an asymmetric periodical characteristic which is reverse to the VIPA plate is configured for the central wavelength in the wavelength regime. With this filter, the transparency characteristic of the wavelength dispersion compensator using the VIPA plate is optimized.

Abstract: Improved optical element wafers comprising stacked, optically coupled etalon wafers are disclosed. Each etalon wafer comprises a bulk optic wafer defining the optic cavity between selectively transparent thin film mirror coatings. The bulk optic wafer comprises an optically transparent body, such as a portion of a substrate wafer, along with a wedge correcting coating on at least one of the two surfaces of the optically transparent body and/or a thickness-adjustment layer on one or both surfaces. The bulk optic wafer is a solid, self-supporting body, optically transparent (at the wavelength or wavelengths of interest), whose thickness, i.e., the dimension between the selectively transparent surfaces, defines the cavity spacing of the bulk optic etalon wafer. Methods of making and using the optical element wafers are also disclosed.

Abstract: A method and system of interference lithography (also known as interferometric lithography or holographic lithography) which utilizes phase-locked, scanning beams (so-called scanning beam interference lithography, or SBIL). The invention utilizes a high-precision stage that moves a substrate under overlapped and interfering pairs of coherent beams. The overlapped beams interfere, generating fringes, which form a pattern “brush” for subsequent writing of periodic and quasi-periodic patterns on the substrate. The phase of the fringes in the overlapped region is phase-locked to the motion of the precision stage. The invention includes methods for forming, overlapping, and phase-locking interfering pairs of beams on a variety of substrates; methods for measuring and controlling the period, phase, and angular orientation of fringes generated by the overlapping beams; and methods for measuring and controlling the effects of stage mechanical and thermal drift and other disturbances during the writing process.

Abstract: A light diffusing film including a film including crystalline polymer compound C laminated to at least one face of an internal light-diffusing film including an islands-in-a-sea structure including a sea component of thermoplastic resin A and an islands component of thermoplastic resin B, wherein thermoplastic resins A and B have different refractive indexes.

Abstract: A method and device is disclosed for relaying a narrow diameter collimated optical beam carrying optical communication signal channels between a multilayer interference filters and another reflective surface avoiding signal loss by routing the optical beam to compensate for beam broadening caused by the multilayer interference filter. The method and device are particularly applicable to dispersion compensating filters, especially those wherein one filter is tunable, in that a controllable amount of dispersion is introduced to offset or compensate dispersion. Preferably one of the filters is a tunable periodic device in the form of a multi-cavity etalon structure. In a preferred embodiment of the filters can be designed to provide various controllable but different constant amounts of dispersion.

Abstract: An optical thin film stack provides reflection of essentially all light except for a selected amount of transmission over a selected wavelength range. Reflecting, rather than absorbing, unwanted light avoids heating caused by light absorption and allows productive use of the non-transmitted light in some applications. In some embodiments, reflector designs are “stacked” on an optical substrate to provide serial optical reflectors. Stacking dichroic filters provides reduced sensitivity to cone angle and manufacturing advantages.

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: A photonic bandgap device includes a first mirror region including alternating layers of different materials. A second mirror region includes alternating layers of different materials. An air gap cavity region is positioned between the first mirror region and second region. The air gap cavity changes its thickness when a voltage is applied so that the device is tuned to a particular resonant wavelength.

Abstract: Provided is an optical multilayer structure having a simpler configuration, flexibility in selection of materials and improved reliability in wiring and capable of high-speed response even in a visible light range. A optical multilayer structure (1) has a first layer (11) being light-absorptive and making contact with a substrate (10), a gap portion (12) having as large a size as light interference phenomenon can occur and being capable of varying the size, and a second layer (13) being transparent in this order on the substrate (10). Where a complex refractive index of the first layer (11) is N1 (=n1?i·k1, n1 is a refractive index, k1 is an extinction coefficient, and i is an imaginary unit), a refractive index of the second layer (13) is n2, and a refractive index of an incident medium is 1.0, the optical multilayer structure (1) is configured so as to satisfy the following formula. ( n 1 - n 2 2 + 1 2 ) 2 + k 1 2 - ( n 2 2 - 1 2 ) 2 = 0.

Abstract: The present invention relates to a heat filter and a process for manufacturing this filter. This heat filter may for example be used to filter surgical or examination lighting composed of a light source which emits energy, or radiation, in the visible and infrared ranges. It allows the light emitted by this source to be filtered so as to prevent infrared radiation from hindering the surgical team or the patient. It includes a substrate, at least one layer of an infrared reflecting material, and a coating forming an interference filter in the visible range. The invention process includes the deposition on a substrate of a layer of an infrared reflecting material and the deposition on this layer of an interference filter in the visible range.

Abstract: The invention provides a substantially athermal etalon. In one embodiment, the multi-cavity etalon includes at least one free-standing multi-layer thin film and is rendered thermally stable through the use of the free-standing multi-layer film and spacers having predetermined thermal expansion coefficients. In another embodiment, the multi-cavity etalon is rendered thermally stable through the use of mixed spacers.

Abstract: A micro-optic Mach-Zehnder interferometer with a differential delay of n bit periods, where n is an integer number, and thermal bias control is useful as a spectral filter in front of a differential detection system to accomplish a balanced receiver. The interferometer may also be arranged as a Michelson interferometer or a dual-plate interferometer.

Abstract: A multi-aperture interferometric optical system collects light propagating from a source of light and develops overlapping diffraction patterns on an optical detector that produces output signals for processing to form an image corresponding to the diffraction patterns. A preferred embodiment of the invention is a large aperture orbiting, earth-watching ring interferometric optical system configured such that there is no macro-structure pointing. Four mirror-ring structures direct incoming light to a multi-spectral primary optical detector that acquires light-pattern information from which an image can be derived.

Abstract: A reflective Ag alloy film includes a Ag—Bi alloy thin film, and a Bi layer and/or a Bi oxide layer formed on the surface and/or between the Ag—Bi alloy thin film and another layer formed on the Ag—Bi alloy thin film. The thickness of the Bi layer and/or the Bi oxide layer is 2.0 nm or below. The Ag—Bi alloy thin film of the reflective Ag alloy film has a Bi content in the range of 0.01 to 3.0 at %. A reflector is formed by depositing the Ag—Bi alloy thin film on a base member.

Abstract: A tunable Fabry-Perot filter includes an optical cavity bounded by a stationary reflector and a deformable or movable membrane reflector. A second electrostatic cavity outside of the optical cavity includes a pair of electrodes, one of which is mechanically coupled to the movable membrane reflector. A voltage applied to the electrodes across the electrostatic cavity causes deflection of the membrane, thereby changing the length of the optical cavity and tuning the filter. The filter with the movable membrane can be formed by micro device photolithographic and fabrication processes from a semiconductor material in an integrated device structure. The membrane can include an inner movable membrane portion connected within an outer body portion by a pattern of tethers. The tether pattern can be such that straight or radial tethers connect the inner membrane with the outer body. Alternatively, a tether pattern with tethers arranged in a substantially spiral pattern can be used.

Abstract: The present invention relates to a projection system that can be applied to a projection TV or a projection monitor, and more particularly, to a projection system that can improve a contrast while maintaining a proper brightness of a set where the projection system is applied.

Abstract: An optical component in the form of a right angled triangular prism having a first side, a second side orthogonal to the first side, and a third side generally inclined to the first and second sides to reflect optical radiation incoming from the first sided towards the second side. The first and second sides have semi-reflecting surfaces acting as etalon surfaces providing an interferometric pattern. The optical transmittance between the first and the second sides is wavelength dependent and the radiation exiting the second side of the component is rotated 90 degrees to the radiation entering the first side.

Abstract: In a multilayered optical thin-film filter having multiple quarter wavelength thick optical thin films with different refractive indices, the filter includes a plurality of unit cavities that are stacked multiple times via a connection layer, each unit cavity including a first reflector layer, a spacer layer in contact with the first reflector layer, and a second reflector layer in contact with the spacer layer. The first reflector layer is a layered body and the second reflector layer is a layered body. The spacer layer is a multilayered optical thin film with a high refractive index obtained by layering even number of films, or is composed of a multilayered optical thin film with a low refractive index. The connection layer is a multilayered optical thin film with a low refractive index obtained by layering odd number of films.

Abstract: An etalon has at least one transparent plate, wherein the transparent plate consists of lithium tantalate single crystal, an etalon has at least one transparent plate, wherein the transparent plate consists of lithium niobate single crystal and a method for producing an etalon, which includes at least growing a single crystal of lithium tantalate or lithium niobate by the Czochralski method, producing a transparent plate from the single crystal and producing an etalon from the transparent plate. There are provided etalons of thin type showing high thermal stability.

Abstract: A mirror which reflects input light from a lens which focuses light emitted from a VIPA, and returns the light to the lens is constituted as a multi-faced mirror including multiple reflection surfaces in the traveling direction of the input light which individually reflect light with a different wavelength, and have a different shape. As a result, an apparatus which has a small optical loss, and generates a different wavelength dispersion depending on a channel signal wavelength of a WDM signal.

Abstract: A projection type display apparatus including an illumination optical system for emitting a light flux, a decomposition optical system for decomposing the light flux into color lights of red, green and blue, liquid crystal light valves for the colors for receiving the decomposed color lights, a synthesis optical system for synthesizing the image lights of the colors from the liquid crystal light valves, and a projection optical system for projecting the synthesized image lights to a screen. A filter is disposed at one of positions opposing to each other across the center of the light flux between the white light source and the decomposition optical system and attenuates or cuts off light of a wavelength region different from that of light which passes the other of the positions.

Abstract: A birefringent dielectric multilayer film that reflects in a wavelength region of interest, and preferably reflects at least 50% of light in a band at least 100 nm wide, preferably positioned between wavelengths from about 700 nm to about 2000 nm. The film is heat set to render the film capable of shrinking to conform without substantial wrinkling to a substrate having a compound curvature. The film may be laminated to form a wide variety of non-planar articles.

Abstract: A multiple wavelength light emitting device is provided wherewith the resonance strength and directivity between colors can be easily adjusted for balance. This light emitting device comprises a light emission means 4 for emitting light containing wavelength components to be output, and a semi-reflecting layer group 2 wherein semi-reflecting layers 2R, 2G, and 2B that transmit some light having specific wavelengths emitted from the light emission means and reflect the remainder are stacked up in order in the direction of light advance in association with wavelengths of light to be output. Light emission regions AR, AG, and AB are determined in association with the wavelengths of light to be output.

Abstract: Various configurations of a virtually imaged phased array (VIPA) generator in combination with a mirror to compensate for chromatic dispersion. A VIPA generator produces a light traveling from the VIPA generator. In some embodiments, a variable curvature mirror is positioned to reflect the light back to the VIPA generator. A rotation axis around which the mirror is rotated and a translation path for the rotation axis are provided, to change the curvature of the mirror where the output light is reflected. In other embodiments, a plurality of mirrors have different surface curvatures. A holder has a rotation axis and holds the plurality of mirrors equidistantly from the rotation axis. The holder is rotatable around the rotation axis to bring a different, respective mirror in position to reflect light produced by a VIPA generator back to the VIPA generator. In other embodiments, a rotating mirror is rotatable about a rotation axis to reflect light produced by a VIPA generator to a respective fixed mirror.

Abstract: A multilayer optical interference filter having a multiplicity of optical cavities separated by a dielectric reflector stacks to achieve either a very narrow passband region or sharp transition between the passband and reflective region is substantially free of stress to preserve the desired optical performance upon fabrication into miniature discrete filter elements. The substantial stress reduction is achieved by removing the filter from the substrate used in the deposition process in a controlled manner to preserve the structural integrity of the resulting free standing multilayer film structure. The structure can be further bonded or attached to other optical components to suppress a thermal shift in center wavelength without reintroducing stress or interposing a massive substrate in the optical path through the filter.

Abstract: An apparatus for detecting wavelength change of a first light signal comprises an amplitude splitting interferometer and a detector. The amplitude splitting interferometer comprises first and second optical paths. The first optical path has a first index of refraction that varies with wavelength over a first wavelength band. The second optical path has a second index of refraction that is relatively constant over the first wavelength band. In operation the first light signal enters and exits the amplitude splitting interferometer forming interference light. The interference light couples to the detector which detects the wavelength change of the first light signal from the interference light. An interferometer comprises a first beam splitter, third and fourth optical paths, and a second beam splitter. The third optical path is optically coupled to the first beam splitter and has a third index of refraction that varies with wavelength over a second wavelength band.

Abstract: An optical apparatus for producing chromatic dispersion. The apparatus includes a virtually imaged phased array (VIPA) generator, a mirror and a lens. The VIPA generator receives an input light at a respective wavelength and produces a corresponding collimated output light traveling from the VIPA generator in a direction determined by the wavelength of the input light, the output light thereby being spatially distinguishable from an output light produced for an input light at a different wavelength. The mirror has a cone shape, or a modified cone shape. The lens focuses the output light traveling from the VIPA generator onto the mirror so that the mirror reflects the output light. The reflected light is directed by the lens back to the VIPA generator. In this manner, the apparatus provides chromatic dispersion to the input light.

Abstract: A method and apparatus for stretching a pulse, shaping a stretched pulse, and modeling a stretched and/or shaped pulse are disclosed. An etalon has a port, a partially reflective surface, and a fully reflective surface. A base pulse is introduced into the etalon, and a plurality of portions of the base pulse propagating from the etalon are collected. The collected portions are then combined to generate a stretched pulse whose width is proportional to the width of the base pulse. This can be modeled by assigning a transmission factor value to each one of a plurality of taps and a reflection factor value to each one of the taps, excepting only one tap. A transport delay for is assigned to each tap to which a reflection factor value was assigned, wherein the transport delay is proportional to the width of a base pulse.

Abstract: An integrated optical monitoring system comprises a hermetic package and an optical bench sealed within the package. An optical fiber pigtail enters the package via a feed-through to connect to and terminate above the bench. A tunable filter is connected to the top of the bench and filters an optical signal transmitted by the fiber pigtail. A detector, also connected to the bench, detects the filtered signal from the tunable filter. Thus, the entire system is integrated together, on a single bench within a preferably small package. This configuration makes the system useful as a subsystem, for example, in a larger system offering higher levels of functionality and optical signal processing capability.

Abstract: An optical device has a light-transmitting optical substrate formed with a multilayer film and a barrier layer disposed on the multilayer film side thereof. The light-transmitting optical substrate has a refractive index Ns (at a reference wavelength of 632.8 nm) falling within the range of 1.7≦Ns≦1.9, whereas the barrier layer has a refractive index Nb (at a reference wavelength of 632.8 nm) falling within the range of −0.1≦Nb−Ns≦0.1.

Abstract: An interleaver is provided with an optical system configured to split light having traveled from a first port to a half mirror, into two beams and direct the beams toward first and second reflectors, respectively. Light reflected by the first reflector and arrived at the half mirror is split into two beams and directed toward second and third ports, respectively. Light reflected by the second reflector and arrived at the half mirror is split into two beams directed toward the second and third ports, respectively. An etalon filter configured to cause a loss on either one of light incident thereto from the first port and the beams directed toward the second port and toward the third port.

Abstract: A method of fabricating optical filter is disclosed. The method includes providing the substrate and selectively etching the substrate to form a plurality of freestanding layers. A plurality of dielectric layers is disposed over an outer surface of each of the freestanding layers. The resultant optical filters may be used in a variety of applications including etalon applications.

Abstract: A manufacturing method for optical interference type panel is provided. A patterned supporting layer is formed on a transparent substrate, and then a first electrode layer and an optical film are formed sequentially on the supporting layer and the transparent substrate. A sacrificial material layer is formed on the optical layer, and then, a backside exposure process is performed by using the supporting layer as a mask to pattern the sacrificial material layer. A portion of the patterned sacrificial material layer is removed to expose the optical film above the supporting layer to form a sacrificial layer, and then a second electrode layer is formed on the sacrificial layer between the adjacent supporting layers and portion of the optical film. Afterwards, the sacrificial layer is removed.

Abstract: The invention provides a multilayer-coated substrate which has recesses and projections of an accurate shape on the surface and has high heat resistance and a high degree of integration, and further provides a process for producing the same.

Abstract: A color shifting multilayer interference film is provided which may be used to produce foils or flakes for use in pigment compositions and colorants having color shifting properties. The flakes can be interspersed into a pigment medium to form paints, inks, or cosmetic preparations which can subsequently be applied to objects, papers, or people. Three and five layer designs of the interference film include alternating layers of a dielectric material and carbon in various configurations. The dielectric layers are formed to have an optical thickness at a design wavelength that provides a color shift as the angle of incident light or viewing angle changes.

Abstract: A color shifting multilayer interference film is provided which may be used to produce foils or flakes for use in pigment compositions and colorants having color shifting properties. The flakes can be interspersed into a pigment medium to form paints, inks, or cosmetic preparations which can subsequently be applied to objects, papers, or people. Three and five layer designs of the interference film include alternating layers of a dielectric material and carbon in various configurations. The dielectric layers are formed to have an optical thickness at a design wavelength that provides a color shift as the angle of incident light or viewing angle changes.

Abstract: An authentication system using a correlator that correlates an input with a reference wherein at least one of the input and reference comprises a phase volume mask having structures, preferably points, that are each less than about six microns in size and can have an aspect ratio (AR) greater than 1:1 so as to produce a phase encoded random pattern having millions of combinations in a mask that is as small as one square millimeter. The random pattern can be convolved with a second pattern, such as a biometric pattern, to produce a phase convolved mask. The correlator preferably is a nonlinear joint transform correlator that can use “chirp” encoding to permit the input to be located in a different plane than the reference. The correlator optically Fourier transforms images of the reference and input that are thereafter nonlinearly transformed and inverse Fourier transformed by a processor to determine the presence or absence of a correlation spike indicative of authenticity.

Abstract: An optical apparatus includes a variable optical-property element to change its optical properties by applying an electric or magnetic field or temperature to a liquid crystal. In this way, the optical apparatus is reduced in thickness, and can be used in a camera, a microscope, etc.

Abstract: The invention provides a multi-cavity filter, and in particular, a multi-cavity bandpass filter having a predetermined centre wavelength. The filter includes a plurality of cavities, each cavity including two partially reflecting films separated by a layer of dielectric material. The two partially reflecting layers are formed from layers of material having alternating high and low refractive indices. Each layer of dielectric material has a thickness that is an integral number of half-waves of the centre wavelength. The filter has an asymmetric structure that causes the reflected chromatic dispersion from one side of the filter to be reduced relative to the reflected chromatic dispersion from the other side.

Abstract: The invention provides a substantially athermal etalon. In one embodiment, the multi-cavity etalon includes at least one free-standing multi-layer thin film and is rendered thermally stable through the use of the free-standing multi-layer film and spacers having predetermined thermal expansion coefficients. In another embodiment, the multi-cavity etalon is rendered thermally stable through the use of mixed spacers.

Abstract: A MOEMS Fabry-Perot tunable filter includes an optical membrane structure. Two electrostatic cavities are provided, one on either side of the membrane structure. As a result, electrostatic attractive forces can be exerted on the optical membrane to enable deflection in either direction, typically, along the optical axis. This is useful in calibrating the tunable filter during operation to an initial wavelength (&lgr;o) set point. It is also useful in controlling the membrane to avoid unstable operation.

Abstract: A variable dispersion compensator comprising: an optical incidence/output device for propagating wavelength division multiplexed light; an optical multiple reflector on which the wavelength division multiplexed light emitted from the optical incidence/output device is incident for repetitive reflections; and an optical reflection device for reflecting the wavelength division multiplexed light emitted from the optical multiple reflector toward the optical multiple reflectors, the device composed of a second lens and a reflecting element and being capable of controlling the distance from the optical multiple reflector. A temperature adjusting element and a temperature detecting element are arranged via a thermal-conductive elastic member on a surface of the optical multiple reflector at a portion where no drop occurs in the intensity of the wavelength division multiplexed light incident/emitted. The temperature of the optical multiple reflector is controlled by a controller.

Abstract: A vehicle rear-view mirror has a light-transmitting filtering layer for filtering out interfering fractions of the light entering the filtering layer in the yellow spectral range. The mirror includes an interference reflector which has a plurality of thin layers for the reflection of the light impinging on the mirror. The degree of reflection of the interference reflector is less in the yellow spectral range than in the green and/or red wavelength range.

Abstract: An optical apparatus for producing chromatic dispersion. The apparatus includes a virtually imaged phased array (VIPA) generator, a mirror and a lens. The VIPA generator receives an input light at a respective wavelength and produces a corresponding collimated output light traveling from the VIPA generator in a direction determined by the wavelength of the input light, the output light thereby being spatially distinguishable from an output light produced for an input light at a different wavelength. The mirror has a cone shape, or a modified cone shape. The lens focuses the output light traveling from the VIPA generator onto the mirror so that the mirror reflects the output light. The reflected light is directed by the lens back to the VIPA generator. In this manner, the apparatus provides chromatic dispersion to the input light.

Abstract: A stress correction film is applied to one side of a VIPA optical element provided with a multi-layer fully reflective film and an anti-reflective film on one surface of a transparent plate, and a semi-transparent multi-layer reflective film on the other surface, in order to adjust the unbalance between the respective stress of the multi-layer films on each surface. In other words, by applying a stress correction film, the unbalance between the respective stress of the multi-layer films on each surface of the VIPA optical element is corrected, and accordingly a VIPA optical element with low profile irregularity can be realized.

Abstract: A multi cavity comb filter for interleaving or de-interleaving WDM signals has a plurality of stacked optical cavities each having substantially the same thickness. The multiple cavity arrangement provides a comb reflection response and a comb transmission response with broad peaks, so that the filter can be used for transmitting one group of channels and reflecting another group of channels at interleaved positions. The cavities are preferably formed from silicon wafers, so that existing techniques can be employed to obtain specific cavity thicknesses with sufficient accuracy and uniformity.

Abstract: A mirror which reflects input light from a lens which focuses light emitted from a VIPA, and returns the light to the lens is constituted as a multi-faced mirror including multiple reflection surfaces in the traveling direction of the input light which individually reflect light with a different wavelength, and have a different shape. As a result, an apparatus which has a small optical loss, and generates a different wavelength dispersion depending on a channel signal wavelength of a WDM signal.

Abstract: The invention relates generally to optical interference filters and interferometers. Methods, devices and device components for optical signal generation and processing using optical interference filters and interferometers are presented. The invention provides optical interference filters and interferometers having a selected cumulative reflectance phase dispersion capable of providing substantially independent selectable resonance frequency and free spectral range. An exemplary interference filter of the present invention provides a multi-peak transmission spectrum with substantially independent, selectable control over absolute transmission band frequencies and relative transmission band spacing. The methods and devices provided herein are particularly well suited for frequency matching optical signals to a selected frequency standard, such as the International Telecommunication Union frequency standard.

Abstract: The present invention discloses a Fabry-Perot optical filter device, which includes a Fabry-Perot element for allowing a light to pass through and optically filtering the light at least twice, and at least one reflecting element for reflecting the light passed through the Fabry-Perot element back to the same Fabry-Perot element during the at least two optical filtering. The Fabry-Perot optical filter device further includes an input terminal used to import the light into the Fabry-Perot optical filter device, and an output terminal used to export the light after the at least two optical filtering.