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: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.

Abstract: A light modulator is arranged as an array of rows and columns of interferometric display elements. Each element is divided into sub-rows of sub-elements. Array connection lines transmit operating signals to the display elements, with one connection line corresponding to one row of display elements in the array. Sub-array connection lines electrically connect to each array connection line. Switches transmit the operating signals from each array connection line to the sub-rows to effect gray scale modulation.

Abstract: A tunable optical resonator for use as a tunable laser or optical filter comprising a cavity in which the cavity is delimited by a reflection grating and a reflector in which the reflection grating is fixed to a flexible support, the resonator also comprising means for flexing the flexible support for causing the grating to mimic rotation about a selected point. A micro-mechanical tunable resonator as above providing mode-hop free tuning.

Abstract: An optical tunable filter includes a first substrate 3 having a light transmitting property which includes a movable portion 31, a second substrate 20 having a light transmitting property which is provided so as to be opposed to the first substrate, a first gap 21 and a second gap 22 which are respectively provided between the movable portion 31 and the second substrate 20, an interference portion which causes interference of incident light between the movable portion 31 and the second substrate 20 through the second gap 22, and a driving portion which changes a distance of the second gap 22 by displacing the movable portion 31 with respect to the second substrate 20 using the first gap 21. This makes it possible to provide an optical tunable filter having a simpler structure and a smaller size, which can be manufactured through a simplified manufacturing process without using a release hole and can achieve stable driving of a movable portion, and a method for manufacturing such an optical tunable filter.

Abstract: A scanning optical monitoring system and method are appropriate for high speed scanning of a WDM signal band. The system and method are able to identify dropped channels or, more generally, discrepancies between the determined or detected channel inventory and a perpetual inventory for the WDM signal, which perpetual inventory specifies the channels that should be present in the WDM signal assuming proper operation of the network. The system includes a tunable optical filter that scans a pass band across a signal band of a WDM signal to generate a filtered signal. A photodetector then generates an electrical signal in response to this filtered signal. A decision circuit compares the electrical signal to a threshold and a controller, which is responsive to the decision circuit, inventories the channels in the WDM signal.

Abstract: A method of tuning a resonant cavity of an FP (Fabry-Perot) interferometer in a DLD (diffractive light device) MEMS (microelectromechanical system) device, wherein the FP interferometer has a top plate and a bottom plate, and wherein the method comprises; using first and second electromechanical transducers to independently change a distance between the top and bottom plates of the FP interferometer.

Abstract: Apparatus and methods for compensation of asymmetric mode pulling in external cavity lasers and the like. An apparatus includes a wavelength locker or etalon device to provide an asymmetric power transfer function and generate a transmission peak or peaks of asymmetric shape. The asymmetry of the transmission peak may be in the form of a steeper slope on the long wavelength side of the peak than on the short wavelength side. The asymmetry of the transmission peak or peaks may be structured to compensate or correct for asymmetric mode pulling effects that arise in laser gain media during single mode laser operation.

Abstract: A shutter device comprises a plurality of shutters. Each of the shutters is provided at a position in the vicinity of a fly's eye lens positioned on the side of a polarization conversion system (one of fly's eye lenses in an integrator lens) and not preventing the passage of effective illuminating light. Each of the shutters is constructed as a first shutter or a second shutter.

Abstract: An Interferometric Modulator (IMod) is a microelectromechanical device for modulating light using interference. The colors of these devices may be determined in a spatial fashion, and their inherent color shift may be compensated for using several optical compensation mechanisms. Brightness, addressing, and driving of IMods may be accomplished in a variety of ways with appropriate packaging, and peripheral electronics which can be attached and/or fabricated using one of many techniques. The devices may be used in both embedded and directly perceived applications, the latter providing multiple viewing modes as well as a multitude of product concepts ranging in size from microscopic to architectural in scope. In another aspect, a structure for modulating light comprises modulators of light each including an interference cavity for causing interference modulation of the light.

Abstract: An interferometric micro electro-mechanical switching (MEMS) device includes an interferometer. The interferometer includes an optical cavity having a depth and formed between an inner mirror assembly and an outer mirror assembly. The MEMS device further includes an actuator coupled to the interferometer. The actuator includes an electrode gap having a depth and formed between an inner conductor and an outer conductor. In one particular embodiment, the depth of the optical cavity and the depth of the electrode gap are capable of being selected substantially independently of one another.

Abstract: A projection display screen that can electrically alter the reflectivity of a region of the projection display screen in response to the intensity of incident projected light that is applied at the region.

Abstract: A spectrally tunable optical detector and methods of manufacture therefore are provided. In one illustrative embodiment, the tunable optical detector includes a tunable bandpass filter, a detector and readout electronics, each supported by a different substrate. The substrates are secured relative to one another to form the spectrally tunable optical detector.

Abstract: The invention relates to a semitransparent mirror and a method for producing and for operating the semitransparent mirror. The semitransparent mirror has a transparent substrate, a first protective layer that is arranged on the substrate, and a layer with a phase change medium, which is arranged on the first protective layer. The layer is covered by a second protective layer that protects the phase change medium.

Abstract: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.

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: Devices based on surface plasmon filters having at least one metal-dielectric interface to support surface plasmon waves. A multi-layer-coupled surface plasmon notch filter is provided to have more than two symmetric metal-dielectric interfaces coupled with one another to produce a transmission spectral window with desired spectral profile and bandwidth. Such notch filters can form various color filtering devices for color flat panel displays.

Abstract: Mechanical control and actuation of an adaptive optical element provides highly stable and repeatable correction of the shape of an optical element to an accuracy of a small fraction of a very short wavelength of light, responsive to a metrology source and sensor arrangement. Actuators in the form of individual set-screws or other actuators capable of axially positioning a shaft are driven by a robotic screw driver with four degrees of freedom or one or more linear actuators to exert force on the mirror. Positive or negative force may be used for outward and/or inward deflection of the mirror. When a desired force is developed on the mirror through a mechanical linkage, the linkage may be clamped by a passive clamp which may be released by an actuator such that the adjustment is maintained while the linear actuator and the clamp actuator are turned off; yielding a highly stable adjustment while effectively removing sources of actuator drift, noise, vibration and heating which may adversely affect stability.

Abstract: An optoelectronic device including a header having an upper surface and including a plurality of conducting pins extending up through the upper surface; an optical device; a tunable optical filter, wherein the optical device and the tunable optical filter are arranged in a vertical stack mounted on and extending above the upper surface of the header and wherein the tunable optical filter is electrically connected to the plurality of conducting pins; and a cap affixed to the header and along with the header defining a sealed interior containing the optical device and the tunable optical filter, wherein the cap has a top surface with a window formed therein, and wherein the window is aligned with the tunable optical filter and the optical device.

Abstract: A fixing structure for fixing a color wheel to a base of a projector is provided. The color wheel is rotatably installed and includes a color rotating disc having a plurality of color filters selectively transmitting light of a predetermined wavelength, and a driving source which drives the color rotating disc. The fixing structure includes a first cover member coupled to a base, and a second cover member coupled to the first cover member and together therewith encompassing the color wheel. A bracket is provided to which the color wheel is coupled, and a coupling unit couples the bracket to the second cover member. A buffer member is provided between the first and second cover members and between the bracket and the second cover member for reducing vibration.

Abstract: A method of calculating an aerial image of a spatial light modulator array includes calculating a pixel interference matrix that represents pair wise interference between pixels of the spatial light modulator array; calculating effective graytones corresponding to modulation states of the pixels; and calculating the aerial image based on the pixel interference matrix and the effective graytones. The graytones depend only on the modulation states of the pixels. The pixel interference matrix depends only on position variables. The position variables are position in an image plane and position in a plane of a source of electromagnetic radiation. The pixel interference matrix can be a matrix of functions. The pixel interference matrix can be a four dimensional matrix. The effective graytones are approximated using sinc functions, or using polynomial functions.

Abstract: A micro electro mechanical systems (MEMS) device includes a first substrate on which an electrode is formed, a movable substrate having at least a moving part and a periphery supporting member, and a second substrate having a concave portion. A space that includes a part of the concave portion is formed by jointing the first substrate, the movable substrate, and the second substrate together. The moving part inside the space moves when a voltage is applied between the electrode and the moving part through the periphery supporting member, and a part of the first substrate protrudes outside a side surface of the second substrate.

Abstract: A wavelength dispersion compensating apparatus of the invention comprises: a VIPA plate capable to output incident lights at different angles according to wavelengths; a variable dispersion diffraction grating which can angularly disperse the lights of respective wavelengths output from the VIPA plate, in a direction substantially perpendicular to a direction of angular dispersion in the VIPA plate and also capable to change an amount of the angular dispersion; a light return apparatus which condenses the output lights from the variable dispersion diffraction grating and reflects them by a mirror, to return them to the VIPA plate side; and a stage rotation mechanism which rotates a movable stage on which the lens and the mirror are mounted, according to a diffraction angle in the variable dispersion diffraction grating, so as to enable wavelength dispersion and wavelength dispersion slope to be given to a WDM light, to be changed independently.

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: An optical switch element is described, which includes a fixed layer disposed outwardly from a substrate and a movable mirror assembly disposed outwardly from the fixed layer. The moveable mirror assembly is operable to move relative to the fixed layer responsive to a voltage applied to the movable mirror assembly. In a particular embodiment, the movable mirror assembly includes an inner strip spaced apart from the fixed layer by a first distance and an outer strip disposed approximately adjacent to the inner strip and spaced apart from the fixed layer by a second distance which is greater than the first distance. The optical transmission of the optical switch element changes depending on the position of the movable mirror assembly.

Abstract: The present invention has an object to provide a control method and a control apparatus for a variable wavelength optical filter, which can reliably and stably control drive conditions of the variable wavelength optical filter, independent of the number of wavelengths to be selectively separated in collective.

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 tunable optical filter (30) includes a thin film waveguide (10) and a ring (308) surrounding the thin film waveguide. The ring can be mechanically pressed inwardly toward or pulled outwardly away from the thin film waveguide by external radial forces (306). A central wavelength of the tunable optical filter can be tuned according to the external radial forces. The thin film waveguide includes a substrate (102) and a multi-layered thin film (104) deposited on the substrate. The multi-layered thin film includes high refractive index layers (106) and low refractive index layers (108) alternately superposed on one another to form the multi-layered structure.

Abstract: The invention relates to an optical system that can be operated with low power consumptions, reduced noises and fast responses, is simplified in mechanical structure and of reduced outer diameter and compact size, and is capable of focusing and zooming. This optical system comprises a rotationally symmetric lens group and an optical element having variable optical properties, whereby focusing or zooming can be performed. Focusing or zooming can be performed by use of a plurality of optical elements having variable optical properties, wherein at least one of the optical elements is configured to a free-form surface shape.

Abstract: In accordance with an exemplary embodiment of the present invention, an optical apparatus includes a glass monolithic structure including a plurality of optical filter elements, and the glass monolithic structure is not an optical fiber. In accordance with another exemplary embodiment of the present invention, an optical apparatus includes a glass monolithic structure which includes a plurality of optical filter elements. The optical apparatus further includes a device which selectively aligns an optical input and an optical output to one of said plurality of optical filter elements. In accordance with another exemplary embodiment of the present invention, a method of adding/dropping a particular frequency from an optical signal includes providing a glass monolithic structure which further includes a plurality of optical filter elements. The method further includes providing a device which selectively aligns an optical input and an optical output to one of the plurality of optical filters.

Abstract: This invention relates to a new optical geometry for using a linear variable filter as an optical spectral filter. An elliptical beam geometry with the minor beam axis oriented along the linearly varying axis of the filter is used. The beam is incident at a slight angle relative to the long axis of the beam. Ultimately this geometry produces a filter which has minimum spectral broadening from both angular and beam extent effects. Furthermore, this geometry results in low back reflectance and higher input beam power damage thresholds. The optical filter includes means for tuning a wavelength response of the filter. Further, the optical filter can afford Add/Drop functionality by providing optical circulators at the input and output ports.

Abstract: A tunable filter includes a polarizing beam splitter and a half-wave plate that produce two equally polarized beams from an arbitrarily polarized input light. The polarized beams are directed toward a tunable component that consists of an optical substrate coated with a filter and a reflective element on its back and front surface, respectively. The pass and stop beams emerging from the tunable component are retro-reflected by roof structures and passed again through the filter. As a result of this combination of components, the filter's performance is not dependent on polarization and the filter's output channels are not shifted or deviated by tuning.

Abstract: An apparatus is described for controlling the optical path length in an optical device, e.g. an interferometer, and more importantly to maintaining the optical path length difference in an interferometer. The apparatus may include an adjustable plate optically coupled with a beamsplitter. The plate may be rotated such that its surface receives light propagated from the beamsplitter at a non-zero incident angle. In one embodiment, temperature sensitivity is addressed by ensuring that the refractive index of the plate is greater than the refractive index of the beamsplitter. In another embodiment, the apparatus includes combination spacers having a component selected in dependence upon a composition, thickness, and orientation of the adjustable plate.

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 tunable optical device includes a thin film device. The thin film device includes a plurality of cavities each including an electro-optic material. The electro-optic material includes an optical characteristic capable of being manipulated by application of an electric field. In this embodiment, at least some of the plurality of cavities are coherently coupled to others of the plurality of cavities. In this embodiment, the plurality of cavities include a sufficient number of cavities to result in an approximately square frequency response for the device.

Abstract: An air-density-tuned interferometer includes: a hermetically sealed enclosure; a front window coupled to the hermetically sealed enclosure; an interferometer residing within the hermetically sealed enclosure; and a pressure changing device coupled to the hermetically sealed enclosure. The interferometer within the enclosure includes: a first glass plate optically coupled to the front window; a first reflective coating coupled to the first glass plate; a second reflective coating optically coupled to the first reflective coating; a second glass plate coupled to the second reflective coating; and a plurality of spacers coupled to the first and second glass plates, forming an optical interometric cavity therein. The pressure changing device manipulates the gas pressure within the cavity.

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: A generalized tunable optical filter with interconnected processing devices, such as unequal arm Mach-Zehnder interferometric devices and ring resonator devices, is described. Each of the processing elements is characterized by a parametric length ?lk=nk?lf where nk is an integer greater than 30 and ?lf is the longest length common to all of the processing elements. The optical filter is tuned by the setting of actuators in the processing elements with each setting corresponding to a predetermined filter response, such as for chromatic dispersion compensation and WDM add/drop multiplexer applications. To determine the design variables of the optical filter, such as the coupling angles ? and parametric lengths ?lk for the processing elements, a methodology of determining these variables from the desired application is also described.

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: 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 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: An environmentally stable Silver containing mirror or thin-film optical filter having very high reflection values over a large spectral and angular range, and a method for constructing the mirror, or thin-film optical filter, comprising using a substrate that has been exposed to an Argon rich ion stream to prepare the surface. A medium index material is then deposed on the surface with Argon ion bombardment. The Silver is then deposited until it is opaque. A second deposition of the medium index material is next done with the Argon ion bombardment. The coating is then followed with a standard ion assisted deposed optical film to maximize reflection at the desired wavelength and angle of incidence.

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: An airgap type etalon has a higher degree of design freedom of a wavelength-temperature characteristic so that such a wavelength-temperature characteristic can be freely adjusted. The airgap type etalon includes a fixing block having one flat surface, and a transparent parallel flat plate having parallel flat surfaces formed with an antireflection coating and a reflection augmenting coating thereon, respectively. The flat surface at the antireflection coating side is joined to the flat surface of the fixing block. A parallel flat spacer has a thickness greater than that of the transparent parallel flat plate and an expansion coefficient different from that of the transparent parallel flat plate. One of the flat surfaces of the parallel flat spacer is joined to the flat surface of the fixing block. A transparent flat plate has opposite flat surfaces formed with an antireflection coating and a reflection augmenting coating thereon, respectively.

Abstract: An optical shutter including a multi-layer fixed filter and a multi-layer movable filter arranged with a gap therebetween controls the transmittance of light passing through the multi-layer filters. The optical shutter includes minute driving elements provided on the movable filter. Operating the minute driving elements varies a distance of the gap defined between the fixed filter and the movable filter. Operation of the movable filter is restricted by a stopper that comes into contact with the movable filter when the gap has the maximum distance and by a bump formed on the fixed filter. The minute driving elements are joined to the movable filter with elastic bonding layers therebetween.

Abstract: A method of finding drive values for an actuation mechanism having three degrees of freedom is provided, that will optimize a predetermined parameter of a system that utilizes the actuation mechanism. In one embodiment, a method of finding drive values for a tunable Fabry-Perot cavity is provided, for driving three independently adjustable actuators such that the cavity mirrors of the tunable Fabry-Perot cavity are maintained in a substantially parallel relationship.

Abstract: A tunable optical filter including at least one deformable membrane actuator. The actuator may include an array of a thousand or millions of individual actuator cells for strength and mechanical robustness. The deformable membrane actuator including a first primary substrate having a first optical portion, an electrically conductive and deformable membrane, an electrically conductive primary substrate electrode and a membrane support structure. The substrate electrode and the membrane support structure are disposed on or adjacent to the first primary substrate, the deformable membrane being supported by the membrane support structure, and a second substrate having a second optical portion. The second substrate is supported by a load support structure disposed on one surface of the deformable membrane and is located a distance from the first substrate.

Abstract: A tunable filter having a top mirror, a bottom mirror, and one or more intervening layers. The one or more intervening layers preferably have a refractive index that changes with temperature. By heating the one or more intervening layers, the wavelength that is selected by the optical filter can be controlled. The one or more intervening layers are preferably heated by passing current through the one or more intervening layers, or by passing current through a separate resistive layer that is thermally coupled to the one or more intervening layers. Such a filter can provide a high degree of wavelength selectivity in a robust and stable manner.

Abstract: An optical micro-electromechanical device includes a substrate and a mirror assembly suspended above the substrate. The mirror assembly includes a torsional beam and a cantilever. The cantilever includes a cantilever first end and a cantilever second end. The cantilever first end is attached to the torsional beam. The cantilever second end supports a mirror head. A connector is attached to the torsional beam. A counterweight is attached to the connector.

Abstract: A wavelength reference (10) including at least one gas-tunable etalons (12). Each etalon (12) has first and second reflective surfaces (20,22), making a reflecting surface pair (23). Each reflecting surface pair (23) surrounds a cavity (16) which is filled with a gas-tunable medium (19) having a variable optical index of refraction. The etalons (12) produce equally-spaced spectral lines (4) which are variable in response to changes in the gas-tunable medium (19) such as varying gas pressure or composition. The spectral lines (4) are tuned to align to an external wavelength standard, preferably an ITU reference grid (2). The properties of the gas-tunable medium (19) are then fixed, preferably by sealing an enclosure (14) which surrounds the etalons (12), so that they act as a wavelength reference (10). The etalon (12) can be a reflective etalon (29) or in an alternate embodiment (60), can be a transmissive etalon (29).