Abstract: A reflection type diffraction grating according to the present invention has a structure in which a metal film as a first layer with reflectance not lower than 30% with respect to the wavelength of incident light and a transparent dielectric film as a second layer are laminated successively on the surface of the reflection type diffraction grating. With respect to the wavelength of incident light, the metal film has a refractive index selected to be not higher than 1.5 and an extinction coefficient selected to be not smaller than 6.0. The transparent dielectric film has a refractive index selected to be in a range of from 1.30 to 1.46, both inclusively, with respect to the wavelength of incident light and has an optical film thickness selected to be in a range of from 0.20? to 0.38?, both inclusively, when ? is the wavelength of incident light.

Abstract: An optical device for enlarging an eye box, the optical device comprising: (a) a first optical expander being carried by, or formed in, a first light-transmissive substrate engaging a first plane; and (b) a second optical expander being carried by, or formed in, a second light-transmissive substrate engaging a second plane being spaced apart from the first plane. The first and the second optical expanders designed and configured such that light passing through the first optical expander is expanded in a first dimension, enters the second light-transmissive substrate through the second optical expander, and exits from the second light-transmissive substrate, expanded in a second dimension, hence enlarging an eye box of the optical device in both the first and the second dimensions.

Abstract: An external cavity laser comprises a laser source, a collimation optical element, a blazed diffraction grating, a transform optical element, and a light modulator. The laser source produces a light output comprising a range of light wavelengths. The collimation optical element couples the laser source to the blazed diffraction grating. The collimation optical element collimates the light output. The blazed diffraction grating diffracts the light output into a first diffraction order. The transform optical element couples the blazed diffraction grating to the light modulator, which is located in a transform plane of the transform optical element. The transform optical element converts the first diffraction order to position in the transform plane by focusing the range of light wavelengths to the transform plane. The light modulator comprises an array of light modulating pixels selectively operable in first mode and second modes.

Abstract: A light modulator includes elongated elements and a support structure. The elongated elements are arranged in parallel. Each element includes a light reflective planar surface with the light reflective planar surfaces lying in one or more parallel planes. The support structure is coupled to the elongated elements to maintain a position of the elongated elements relative to each other and to enable movement of each elongated element between a first modulator configuration and a second modulator configuration. In the first modulator configuration, the elongated elements act to reflect an incident light as a plane mirror. In the second modulator configuration, selected groups of elements are deflected and act to diffract the incident light along one or more of a plurality of diffraction planes. The groups of elements are configured according to one of a plurality of selectable group configurations. Each group configuration corresponds to one of the plurality of diffraction planes.

Abstract: A first diffractive optical element pattern with a pattern pitch that is no greater than a wavelength of incident light is formed on a first main surface of substrate such as a glass plate. Second diffractive optical element patterns are formed at positions that are respectively incident to positive first-order diffracted light and negative first-order diffracted light produced by the first diffractive optical element pattern. Negative first-order diffracted light produced by each second diffractive optical element pattern is incident upon a boundary face of the substrate at an angle that is smaller than the critical angle, and so exits the substrate.

Abstract: An optical system provides high-contrast operation by collecting zero order light. The optical system comprises a light modulator and a collector. The light modulator is preferably a grating light valve™ light modulator including a plurality of elements selectively operable in a first mode and a second mode, wherein a gap between adjacent elements is equal to or less than a wavelength of an incident light beam. The plurality of elements in the first mode reflect light along a return path, where the plurality of elements in the second mode direct light away from the return path. The collector is coupled to the light modulator to collect zero order light along the return path while the plurality of elements are in the first mode and to collect zero order light along the return path while the plurality of elements are in the second mode.

Abstract: A high-resolution spatial light modulator and systems incorporating the modulator. The modulator includes an array of optically multistable reflective elements disposed on a substrate and each of the reflective elements are capable of structural change into one of a plurality of stable states wherein each of the reflective elements maintains a stable optical property. A computer selectively controls the state of the array of reflective elements to thereby cause each reflective element of the array to selectively reflect incident light such that the array of reflective elements can generate a desired holographical or optical image.

Abstract: The invention is directed to metal-free grating for use in wavelength optical communications, and in particular to metal-free, reflective immersed diffraction gratings. The gratings of the invention area made of at least a first material 1 of refractive index n1 and a second material of refractive index n2. Materials 1 and 2 must obey the Expressions: (I) n1>n2, (II) n1>&lgr;/2L>n2 for single diffracted order at Littrow, and (III) n2/n1<Sin|&thgr;j|<1; wherein &lgr; is the wavelength of the light incident on the grating, &thgr;j represents any and all propagation angles of incident and diffracted light, and L is the grating period. The grating profile is located at the interface of material 1 and to material 2. In one embodiment, the grating profile is made from additional material 3 and 4 of refractive index n3 and n4, respectively, and is placed between materials 1 and 2. In another embodiment the grating is made from silicon.

Abstract: A 2D diffraction grating light valve modulates an incident beam of light. A plurality of elements each have a reflective surface with their respective reflective surfaces substantially coplanar. Alternatively, the reflective surfaces of the plurality of elements lie within one or more parallel planes. The elements are supported in relation to one another. Preferably, a planar member includes a plurality of holes arranged in a symmetrical two-dimensional array and configured such that the holes substantially optically extend the elements. Alternatively, one or more elements substantially optically extends the plurality of holes. The planar member includes a light reflective planar surface that is parallel to the plane of the elements within a functional area of the device. The planar member is supported in relation to the elements. By applying an appropriate biasing voltage to the planar member, the planar member can be moved in a direction normal to the plane of the elements.

Abstract: A durable silver film thin film coated non-planar optical element has been developed to replace Gold as a material for fabricating such devices. Such a coating and resultant optical element has an increased efficiency and is resistant to tarnishing, can be easily stripped and re-deposited without modifying underlying grating structure, improves the throughput and power loading of short pulse compressor designs for ultra-fast laser systems, and can be utilized in variety of optical and spectrophotometric systems, particularly high-end spectrometers that require maximized efficiency.

Abstract: A dispersion compensator having relatively uniform transmission characteristics over the bandwidth of a communication channel. The compensator is designed to process an optical signal corresponding to the communication channel by decomposing that signal into spectral components, routing different components along different optical paths that impart relative delays between the components, and recombining the delayed components spatially and directionally to generate a processed optical signal with reduced chromatic dispersion. In one embodiment, the compensator includes a diffraction grating optically coupled to a mirror array, in which different mirrors receive light corresponding to different communication channels. For each channel, a desired group delay value is produced by selecting the curvature of the corresponding mirror. A compensator employing independently addressable, variable-curvature mirrors enables generation of variable, channel-specific group delays.

Abstract: One embodiment disclosed relates to a system for modulating a plurality of micro-electromechanical (MEM) devices. The system includes a means for providing an amplitude modulation signal to each MEM device at a base frequency and a means for providing a width modulation signal at the base frequency. In addition, the system includes a clock means for providing a higher-frequency clock signal with a frequency that is a multiple of the base frequency. In this embodiment, the width modulation signal for each MEM device indicates at least one position on the higher-frequency clock signal.

Abstract: An optical device for making light converge produces a convergent light beam with a satisfactorily great numerical aperture and acceptably small aberrations. The optical device has a plurality of diffraction gratings that each make light converge. The light shone into the optical device is passed through one after another of those diffraction gratings in such a way that the light is made to converge to a higher degree every time it passes through one of the diffraction gratings. The diffraction gratings may be all transmissive, all reflective, or a combination of both. The diffraction gratings are formed on a surface of or at an interface inside the optical device, and two diffraction gratings may be formed on a single surface. The light is made to eventually converge on the exit surface of the optical device so that the optical device functions as a solid immersion device.

Abstract: The invention is directed to metal-free grating for use in wavelength optical communications, and in particular to metal-free, reflective immersed diffraction gratings. The gratings of the invention area made of at least a first material 1 of refractive index n1 and a second material of refractive index n2. Materials 1 and 2 must obey the Expressions: (I) n1>n2, (II) n1>&lgr;/2L>n2 for single diffracted order at Littrow, and (III) n2/n1<Sin |&thgr;j|<1; wherein &lgr; is the wavelength of the light incident on the grating, &thgr;j represents any and all propagation angles of incident and diffracted light, and L is the grating period. The grating profile is located at the interface of material 1 and to material 2. In one embodiment, the grating profile is made from additional material 3 and 4 of refractive index n3 and n4, respectively, and is placed between materials 1 and 2. In another embodiment the grating is made from silicon.

Abstract: A diffraction grating providing reduced polarization dependent loss. The elements of pixels of the diffraction grating are fixed or actuated such that some grating elements are actuated to correspond to a positive polarization dependent loss and others are actuated to correspond to a negative polarization dependent loss. The pixels may include multiples of three grating elements or multiples of four grating elements. An electrostatic beam structure providing increased actuation in a direction away from a substrate may be used in a diffraction grating providing reduced polarization dependent loss.

Abstract: An electromagnetic radiation diffuser, operative at extreme ultraviolet (EUV) wavelengths, is fabricated on a substrate. The diffuser comprises a randomized structure having a peak and valley profile over which a highly reflective coating is evaporated. The reflective coating substantially takes the form of the peak and valley profile beneath it. An absorptive grating is then fabricated over the reflective coating. The grating spaces will diffusely reflect electromagnetic radiation because of the profile of the randomized structure beneath. The absorptive grating will absorb the electromagnetic radiation. The grating thus becomes a specialized Ronchi ruling that may be used for wavefront evaluation and other optical diagnostics in extremely short wavelength reflective lithography systems, such as EUV lithography systems.

Abstract: We describe an optical spectral filtering device and associated method for selectively directing a portion of a wavelength multiplexed input signal, entering through an optical fiber, into one or more output signals provided to one or more optical fibers and/or electronic outputs. The optical filtering is accomplished using free-space diffractive wavelength demultiplexing optics combined with a fixed (permanent) patterned structure located in the spectrally dispersed image plane. The structure can block or direct a selected spectral portion of the optical signal to one or more separate outputs, such as an optical fiber or power detector. A single active element in the optical path is used to spatially shift, or steer, the entire input spectrum at the dispersed spectral image plane, to control the portion of the input spectrum illuminating specific features on the permanent patterned structure.

Abstract: An optical arrangement has a light source which emits coherent light of a specific wavelength. Further provided is an optical Littrow grating, arranged at a specific Littrow angle &thgr;L. It has a multiplicity of parallel diffraction structures following one another periodically at an interval in each case of one specific grating period and arranged on a substrate predetermining a base area. The light wavelength, the grating period and the Littrow angle &thgr;L are tuned to one another in such a way that the grating is used in one of the largest diffraction orders m for light reflected back at the Littrow angle &thgr;L, which still fulfils the condition: (2(m+1)/m−1) sin (&thgr;L)≧1 An optical arrangement of this kind has an increased reflection efficiency.

Abstract: A diffraction grating includes a metallic base layer and layers of dielectric materials of varying refractive index, where a bottom interface of the layers is adherent to the metallic base layer. The dielectric layers are periodically spaced on top of the metallic base layer, leaving the metallic base layer exposed in regions. This grating allows for the polarization insensitive reflective properties of the base metallic layer to operate in conjunction with the polarization sensitive diffraction properties of the multilayer grating structure to provide near 100% diffraction efficiency over a reasonable wavelength bandwidth, independent of the polarization of the incident beam.

Abstract: In a method of registering an image on a substrate, the substrate is placed on a substrate support and a radiation beam is directed toward the substrate. The radiation beam is reflectively diffracted to modulate the intensity of the radiation beam. The modulated radiation beam is scanned across the substrate to register an image on the substrate. In one version, the radiation beam is a laser beam which is projected onto a mask blank to form a mask.

Abstract: A first diffractive optical element pattern with a pattern pitch that is no greater than a wavelength of incident light is formed on a first main surface of substrate such as a glass plate. Second diffractive optical element patterns are formed at positions that are respectively incident to positive first-order diffracted light and negative first-order diffracted light produced by the first diffractive optical element pattern. Negative first-order diffracted light produced by each second diffractive optical element pattern is incident upon a boundary face of the substrate at an angle that is smaller than the critical angle, and so exits the substrate.

Abstract: A lamellar volume grating operating in reflection and transmission and providing a substantially wavelength- and polarization-independent diffraction efficiency is disclosed. The lamellar grating has an approximately rectangular grating profile with a height-to-width ratio of the grooves or “teeth” advantageously greater than 2. The grating operates preferably in first order and can be implemented as an immersion grating. In particular, the lamellar volume grating described herein can be employed in an optical multiplexer/demultiplexer arrangement with small overall dimensions.

Abstract: An apparatus having an improved, tunable gamma response is disclosed. The apparatus comprises a light modulator having a plurality of spaced-apart elements, composed of alternating active elements and passive elements lying in a single plane; a gamma controller; and a displacement controller. The gamma controller applies a gamma voltage to a substrate, displacing the plurality of spaced-apart elements to a bias plane, closer to the substrate. In a reflection mode, the plurality of spaced-apart elements function as a spectral mirror to an impinging light beam. In a diffraction mode, the displacement controller applies a displacement voltage to the active elements. The active elements are now moved to a second plane parallel to the bias plane so that the light beam impinging on the light modulator will be diffracted. The illumination intensity of a detected light signal is proportional to the displacement voltage raised to a power of between approximately 1.75 and 3.0, the gamma response.

Abstract: The invention provides an optical switcing device, including a substrate having at least one polarization-selective multiplexing grating; at least one polarization-selective demultiplexing grating, and a polarization rotation element acting as a dynamic ½ &lgr; plate, optically interposed between the optical path of said multiplexing grating and said demultiplexing grating. The invention also provides a method for producing an holographic plate having a plurality of holographic elements.

Abstract: A grating light valve has with a plurality of spaced reflective ribbons are spatially arranged over a substrate with reflective surfaces. The grating light valve is configured to optimized the conditions for constructive and destructive interference with an incident light source having a wavelength &lgr;. The grating light valve preferably has a set of movable active ribbons alternating between the set of stationary bias ribbons. The active ribbons and the bias ribbons are spatially separated over the substrate surface such that reflective regions of the substrate surface correspond to the spaces between the ribbons. The ribbons and reflective regions of the substrate optically and geometrically optimized for to generate the conditions for constrictive and destructive interference with the incident light source.

Abstract: A method of preparing a composite micro relief element. The micro relief element comprises a first layer of a first substrate and a second layer of a relief forming polymer comprising an overlay and at least one relief feature portion. The method includes the steps of forming a line of contact between the receptive surface and at least one mold feature formed in a flexible dispensing layer, applying a quantity of resin to fill the mold feature along the line of contact. Moving the line of contact across the receptive surface whereby sufficient resin is captured by the mold feature and a quantity of resin passes the line of contact to form the overlay portion. The resin is then cured and the flexible dispensing layer is released.

Abstract: A light modulator includes elongated elements arranged parallel to each other. In a first diffraction mode, the light modulator operates to diffract an incident light into at least two diffraction orders. In a second diffraction mode, the light modulator operates to diffract the incident light into a single diffraction order. Each of the elongated elements comprises a blaze profile, which preferably comprises a reflective stepped profile across a width of each of the elongated elements and which produces an effective blaze at a blaze angle. Alternatively, the blaze profile comprises a reflective surface angled at the blaze angle. Each of selected ones of the elongated elements comprise a first conductive element. The elongated elements produce the first diffraction when a first electrical bias is applied between the first conductive elements and a substrate.

Abstract: An optical MEM device is encapsulated with a dampening gas to reduce oscillatory vibrations of movable parts during the operation of the device. Preferably, the dampening gas comprises one or more noble gases, such as neon and/or krypton with a partial pressure in a range of 50 to 100% of the total dampening gas pressure. In further embodiments, the dampening gas comprises a mixture of one or more noble gases and an inert carrier gas, such as nitrogen. Preferably, the optical MEM device is sealed within a die with a dampening gas pressure between 0.5 to 3.0 atmospheres at 20 degree Celsius. The current invention is particularly useful for reducing oscillatory vibrations of optical MEM devices having a plurality of movable ribbon structures configured to modulate light with one or more wavelengths in the near infrared (800 to 4000 nanometers) and which operate at high switching rates (4-40 Volts/nano second) and at high switching frequencies (1 kHz and greater).

Abstract: In one embodiment of the invention, a grating structure etched on a mirror substrate has a grating period causing diffracting, out of an optical path, a first incident radiation within a first band around a first wavelength. A multi-layer coating deposited on the grating structure reflects the first incident radiation, in the optical path, within the first band and a second incident radiation within a second band around a second wavelength. In another embodiment, a first multi-layer coating deposited on a mirror substrate reflects a first incident radiation within a first band around a first wavelength and a second incident radiation, in an optical path, within a second band around a second wavelength. A grating structure is deposited on the first multi-layer coating. The grating structure is etched to have a grating period causing diffracting, out of the optical path, the second incident radiation within the second band.

Abstract: In one embodiment of the invention, a grating structure etched on a mirror substrate has a grating period causing diffracting, out of an optical path, a first incident radiation within a first band around a first wavelength. A multi-layer coating deposited on the grating structure reflects the first incident radiation, in the optical path, within the first band and a second incident radiation within a second band around a second wavelength. In another embodiment, a first multi-layer coating deposited on a mirror substrate reflects a first incident radiation within a first band around a first wavelength and a second incident radiation, in an optical path, within a second band around a second wavelength. A grating structure is deposited on the first multi-layer coating. The grating structure is etched to have a grating period causing diffracting, out of the optical path, the second incident radiation within the second band.

Abstract: The present invention provides an easily aligned, all-reflective, aberration-free pulse stretcher-compressor in a compact geometry. The stretcher-compressor device is a reflective multi-layer dielectric that can be utilized for high power chirped-pulse amplification material processing applications. A reflective grating element of the device is constructed: 1) to receive a beam for stretching of laser pulses in a beam stretcher beam path and 2) to also receive stretched amplified pulses to be compressed in a compressor beam path through the same (i.e., common) reflective multilayer dielectric diffraction grating. The stretched and compressed pulses are interleaved about the grating element to provide the desired number of passes in each respective beam path in order to achieve the desired results.

Abstract: A renewable liquid reflection grating. Electrodes are operatively connected to a conducting liquid in an arrangement that produces a reflection grating and driven by a current with a resonance frequency. In another embodiment, the electrodes create the grating by a resonant electrostatic force acting on a dielectric liquid.

Abstract: An authenticity identifying film (10) has a reflective film (11) having a circularly polarized light selectivity to reflect at least only either of right-handed circularly polarized light and left-handed circularly polarized light of incident light to produce reflected light. The reflective film (11) is provided with a hologram forming part (11a). The hologram forming part (11a) reflects circularly polarized light of the same circular polarization as that of the reflected light in a direction different from that of the reflected light to form a holographic image. The reflected light reflected by the reflective film (11) and the holographic image formed by the hologram forming part (11a) are detected by detectors disposed at different positions, respectively.

Abstract: The invention provides a planar waveguide diffractive 1×N beam splitter/coupler. It utilizes an integrated circuit fabrication process to fabricate an integrated optic. A Fourier transform diffractive optical element (DOE) is formed on one end of a planar waveguide (planar lightwave circuit; PLC). Thus, an incident beam coming from one end of the planar waveguide can be diffracted into a plurality of output beams. On the other hand, a plurality of incident beams coming from one end of the planar waveguide can be coupled into one output beam. The beam splitter/coupler is easy to fabricate, small in size and more flexible for applications.

Abstract: A micromechanical reflection phase grating may be formed of spring-like ribbon reflectors that are secured to a transparent cover positioned over a substrate such as a silicon substrate. The ribbon reflectors are formed independently of the silicon substrate. If a defect occurs in the phase grating and particularly the ribbon reflectors, the top plate assembly can be reworked or discarded without sacrificing the relatively expensive silicon substrate.

Abstract: A diffuser is disclosed which transmits or reflects incident light into a specific range of angles. In a preferred embodiment, this light is uniformly scattered throughout a cone of angles. The diffuser consists of two parts. The first part diffracts or reflects light into a specific offset angle. The second part, in the preferred embodiment, uniformly scatters the light through a range of angles, which is centered on the offset angle. The diffusers have utility in applications such as screens for wrist watches, computers, calculators, and cell phones.

Abstract: A diffraction grating (1) has a multiplicity of parallel diffraction structures succeeding one another periodically. The latter are arranged on a support (2) and each incorporate a slat (3) extending from a base area (4) of the support (2). Said slat has a substantially rectangular cross-section. The width w of the slat (3) comes to less than 100 nm, preferably between 20 nm and 60 nm, more preferably in the area of 50 nm. Advantageous uses of the diffraction grating (1) are obtained e.g. in a Littrow configuration, preferably in third order of the incident light beams (8), in particular at a light wavelength that is less than 250 nm.

Abstract: An external resonator type wavelength variable light source comprises a semiconductor laser 5 formed on one end face with a antireflection coating 5a, a lens 6 for converting emitted light from the end face of the semiconductor laser 5 formed with the antireflection coating 5a into collimated light, a diffraction grating 7 for selecting a wavelength of the collimated light provided through the lens 6 and diffracting the light, and a mirror for reflecting the light diffracted through the diffraction grating 7 and feeding back the light again diffracted through the diffraction grating 7 into the semiconductor laser 5 through the lens 6. A V-groove grating mirror 8 having reflecting faces with an arrangement like a grating, of a plurality of V grooves 2 each shaped like V at right angles in cross section in a base material 1 with a reflection coating 3 formed on the surface of each V groove is used as the mirror.

Abstract: An electromechanical conformal grating device having a period &Lgr;, that includes: an elongated ribbon element including a light reflective surface; a pair of end supports for supporting the elongated ribbon element at both ends over a substrate; an intermediate support; and means for applying a force to the elongated ribbon element to cause the element to deform between first and second operating states, where in the second operating state the elongated ribbon element mechanically conforms to the intermediate support forming a conformal grating having alternating raised and lowered portions, and wherein the length of the raised and lowered portions are substantially equal.

Abstract: A diffractive optical element acts as a lens. The optical element has a diffraction grating. The diffractive grating is provided with a plurality of ridges. Each of the ridges has a transmissive surface. A sectional profile of the transmissive surface is composed of a plurality of successively connected strait lines of an identical length. The length varies from one ridge to another.

Abstract: The current invention is directed to devices and systems with patterned reflective surfaces. The reflective surfaces are patterned with primary reflective regions and gap regions. The gap regions provide for separation between reflective material within adjacent primary reflective regions. The separation between reflective material reduces atomic flux which can lead to the depletion of the reflective material within regions of the reflective surface that are exposed to an intense light source. The primary reflective regions are preferably formed from a reflective material such as aluminum, silver, gold or platinum. The gap regions are left vacant or deposited with second material which is non-reflective, reflective or semi-reflective. The patterned reflective surface is preferably formed on a micro-structure, such an elongated ribbon. The patterned ribbon structure is preferably one of a plurality patterned ribbon structures in a grating light valve device.

Abstract: An optical system having at least one switched mirror for switching and routing at least one incident beam of electromagnetic radiation. The switched mirrors are controlled by a voltage source and based upon the desired controllability of the switched mirrors and wide range of switching and or routing of an optical signal can be effected. In addition by the selective placement of components with the optical system polarization effects can be controlled with the optical system to more effectively provide for subsequent signal transmission.

Abstract: Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

Abstract: A flat illuminant emits a beam of light toward a reflective scale having predetermined reference gratings formed thereon. A photoreceptive module is placed at a location between the flat illuminant and the reflective scale and closer to the flat illuminant. The photoreceptive module includes an array of photoreceptive devices, which also serves as illuminant-side gratings for partially shielding the beam from the flat illuminant.

Abstract: An overcoat protected diffraction grating. A replica grating having a thin aluminum reflective grating surface is produced by replication of a master grating or a submaster grating. The thin aluminum reflective surface may be cracked or have relatively thick grain boundaries containing oxides and hydroxides of aluminum and typically is also naturally coated with an aluminum oxide film. The grating is subsequently recoated in a vacuum chamber with a thin, pure, dense aluminum overcoat and then also in the vacuum the aluminum overcoat is coated with a thin film of MgF2. The grating is especially suited for use for wavelength selection in an ArF laser operating producing an ultraviolet laser beam at a wavelength of about 193 nm. The oxygen free aluminum overcoat prevents the ultraviolet light from causing damage by stimulating chemical reactions in grating materials under the aluminum grating surface or in the aluminum oxide film. The MgF2 additionally prevents oxidation on the surface, of the aluminum overcoat.

Abstract: A light modulator includes elongated elements arranged parallel to each other and suspended above a substrate. The light modulator operates in a first diffraction mode and in a second diffraction mode. In the first diffraction mode, an incident light diffracts into at least two diffraction orders. In the second diffraction mode, the incident light diffracts into a single diffraction order. Each of the elongated elements comprises a central blazed portion, a first outer blaze transition, and a second outer blaze transition. The central blaze portion couples the first outer blaze transition to the second outer blaze transition. Each of the central blazed portions comprises a reflective surface. Selected ones of the central blazed portions comprise a first conductive element. The first outer blaze transition and the second outer blaze transition are coupled to the substrate. The substrate comprises a second conductive element.

Abstract: A light modulator includes elongated elements arranged parallel to each other. In a first diffraction mode, the light modulator operates to diffract an incident light into at least two diffraction orders. In a second diffraction mode, the light modulator operates to diffract the incident light into a single diffraction order. Each of the elongated elements comprises a blaze profile, which preferably comprises a reflective stepped profile across a width of each of the elongated elements and which produces an effective blaze at a blaze angle. Alternatively, the blaze profile comprises a reflective surface angled at the blaze angle. Each of selected ones of the elongated elements comprise a first conductive element. The elongated elements produce the first diffraction when a first electrical bias is applied between the first conductive elements and a substrate.

Abstract: The optical system of this invention is an unique type of imaging spectrometer, i.e. an instrument that can determine the spectra of all points in a two-dimensional scene. The general type of imaging spectrometer under which this invention falls has been termed a computed-tomography imaging spectrometer (CTIS). CTIS's have the ability to perform spectral imaging of scenes containing rapidly moving objects or evolving features, hereafter referred to as transient scenes. This invention, a reflective CTIS with an unique two-dimensional reflective grating, can operate in any wavelength band from the ultraviolet through long-wave infrared. Although this spectrometer is especially useful for rapidly occurring events it is also useful for investigation of some slow moving phenomena as in the life sciences.

Abstract: The back surface of a BOE (binary optical element) having a binary optical structure formed thereon is coated with a resist film. Chromium is then deposited on the BOE by means of electron beam evaporation so as to form an island structure with an island size of about 50 nm and an island-to-island distance of about 80 nm. The BOE is then etched with an etchant to a depth of 55 nm using the island structure as a mask thereby forming a pillar-shaped microstructure. The island structure used as the mask is removed by means of wet etching using an etchant, and the resist film on the back surface of the BOE is removed using a resist remover. Thus, a microstructure is obtained which has antireflection capability allowing suppression of reflection to a level of 1% or less for a wavelength of 248 nm.

Abstract: A tunable optical filter includes a movable reflector, such as a three-dimensional microelectromechanical system (MEMS) actuated mirror and a plurality of holographic gratings each having a predetermined Bragg wavelength to select the wavelength to be filtered or dropped from broadband or wavelength-multiplexed input optical signals.