Abstract: An apparatus for filtering electromagnetic waves and sensing deposition of chemical species, the apparatus having a substrate having a surface relief structure containing at least one dielectric body with physical dimensions smaller than the wavelength of the filtered electromagnetic waves, such structures repeated in a two dimensional array covering at least a portion of the surface of the first substrate. The apparatus may include one, two, or more such arrays, spaced from one another to create one or more cavities between the arrays.

Abstract: An optical device for receiving input light and for acting on the input light to produce output light includes a first reflector and a second reflector supported in a spaced-apart, confronting relationship with the first reflector such that the input light received by the optical device, at least potentially, undergoes multiple reflections between the first and second reflectors. At least a selected one of the first and second reflectors is configured to subject each one of a plurality of different portions of the input light to one of a plurality of different reflectance values to produce an emitted light passing through at least the selected reflector in a way which is combinable to generate the output light.

Abstract: An object of the invention is to provide a wavelength locker which has a wider locking range than that of the wavelength locker in the prior art and which can cope with a plurality of wavelengths. The aforementioned objects are achieved by a wavelength locker, which comprises a periodic filter, a detecting part for detecting the intensity of a laser beam through the periodic filter, and a controlling part for controlling the wavelength of the laser beam to a desired wavelength in accordance with the output of the detecting part. In this wavelength locker, the FSR of the periodical filter is controlled according to space between the wavelengths, and refers to the number of wavelength to be locked, so that the characteristics corresponding to output wavelengths that vary in every period twice the space of wavelengths and are complementary to each other, can be obtained, and the locking range will become wider.

Abstract: A method and system for performing swept-wavelength measurements within an optical system provides improved operation in resonator-enhanced optical measurement and data storage and retrieval systems. The system includes an illumination subsystem having a swept-wavelength mode, a detection subsystem, an interferometer or an optical resonator interposed in an optical path between the illumination subsystem and the detection subsystem and a time domain analysis subsystem. Multiple resonance points of the optical resonator are detected by the time-domain subsystem when the illumination subsystem is in the swept-wavelength mode in order to determine resonator or interferometer characteristic changes. The resulting information can be used directly as a measurement output, or cavity length information may also be used to adjust the operating wavelength of a constant wavelength mode of the illumination subsystem.

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: A detunable Fabry-Perot interferometer, and method of tuning a Fabry-Perot interferometer are provided. The Fabry-Perot interferometer includes a first mirror, a second mirror oriented with respect to the first mirror so as to define a Fabry-Perot cavity therebetween, and an actuator configured to adjust a resonant wavelength of the Fabry-Perot cavity by varying a gap between the first and second mirrors, wherein the actuator is configured to selectively maintain the first and second mirrors in a substantially non-parallel relationship while the resonant wavelength of the Fabry-Perot interferometer is varied. The detunable Fabry-Perot interferometer can be employed in a multiplexer of a telecommunications system, as provided.

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: Fine-tuning of the optical path length in etalon cavities is achieved by slight variations of the cavity's index of refraction. Such index of refraction variations are accomplished by varying the relative gas mixture in gas-gap etalons or UV-exposing doped glass layer(s) in solid etalons or gas-gap+glass etalons.

Abstract: Thin film filters have been a basic building block of many wavelength division multiplexed (WDM) systems providing the means by which a signal, defined by a center wavelength, can be separated from a group of WDM signals. In an effort to maintain the same performance over a range of operating temperatures, thin film filters have been coated onto specially designed substrates, which expand and contract with the change in temperature to counteract the effects that the temperature change has on the thin film filters. Unfortunately, only very few materials provide the necessary thermal expansion characteristics to counteract the shift in center wavelength. Moreover, the application of a force onto only one side of the filter causes the thin film filter to bend or curve. Accordingly, the present invention solves the aforementioned problems by providing a thin film filter sandwiched between a substrate and a superstrate, which apply equal forces to each side of the filter.

Abstract: A method and system for controlling resonance within a resonator-enhanced optical system provides improved tracking performance in resonator-enhanced optical measurement and data storage and retrieval systems. The system includes an illumination subsystem and a detection subsystem with an optical resonator interposed in an optical path between the illumination subsystem and the detection subsystem. The resonance of the optical resonator is tuned, either by changing the wavelength of the illumination subsystem or the geometric path length within the resonator. Closed-loop feedback control signals can thereby maintain resonance at a desired operating point. The feedback control signal components can be further used to provide measurement data if the resonance of the optical resonator is a function of a measured surface, such as when a reflective surface of the resonator is a surface under measurement.

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.

Abstract: Methods for using the length dispersion of an etalon to approximate desired resonant frequencies. A featured method comprises defining target resonant frequencies; and selecting an etalon having resonant frequencies that approximate the target resonant frequencies, wherein the selection of the etalon is made based at least in part in consideration of a length dispersion of the etalon. A second featured method comprises defining target resonant frequencies; determining a material dispersion for an etalon; and selecting a length dispersion for the etalon suitable to cooperate with the material dispersion to produce resonant frequencies which approximate the target resonant frequencies. Length dispersion selection may include, for example, selection of one or more of a refractive index step, a number of layers, and a layer thickness of one or both dielectric stacks of the etalon.

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.

Abstract: Wavelength locked feedback loops are provided in frequency guide filters, and particularly in sliding frequency guide filters, wherein the wavelength locked feedback loop allows precise control over the location of the filter center wavelength with respect to a transmitted soliton center wavelength, compensating for factors such as the filter rolloff, signal spectral width, and changes in the transmission line properties due to temperature, microbending, aging and other effects. This approach allows the construction of very inexpensive frequency guiding filters, which can be based on low precision frequency domain filters with active compensation. These advantages make it possible to design new types of dispersion managed soliton optical transmission networks.

Abstract: A multi-wavelength etalon comprises at least two regions with different indices of refraction. The change in refractive index alters the wavelengths of incident light, and thus the number of wavelengths between the reflective surfaces of the etalon, and therefore the etalon's transmission characteristics. By selecting specific indices of refraction, an etalon can be provided which produces peaks and troughs at preselected wavelengths in each region. The transition between two adjacent regions with different indices of refraction can be graded to reduce optical interference which may result from an abrupt transition.

Abstract: A micro-mechanical optical modulator having a movable membrane that is spaced from a multi-layer mirror that is disposed on a substrate. The multi-layer mirror includes an anti-reflection layer that is disposed on the substrate, and a coating layer that is disposed on the anti-reflection layer. The combined thickness of the membrane and the coating layer is equal to an integer multiple of one-half of the operating wavelength of the modulator. This thickness restriction is different than prior art Fabry-Perot cavity modulators, which typically independently restrict membrane thickness and coating layer thickness, each to multiples of one quarter of the operating wavelength. By relaxing the requirements imposed by the prior art on layer thickness, modulator performance parameters can be optimized. Specifically, optical bandwidth can be traded for insertion loss and vice versa, as suits the specifics of a particular application.

Abstract: A beam deflector 1 for a beam of light 9 comprises: a first plate of electro-optical material disposed between a pair of electrode arrangements and a pair of plano-parallel mirrors, the refractive index of the electro-optical material being variable by the application of electric voltages, wherein a first mirror of the pair facing towards the incident light has a lower reflectivity than the second mirror, the first or second mirrors comprising a plurality of dielectric layers having refractive indices different from each other. Further, a switching system comprises: a plurality of terminals (53) for optical signals and beam deflectors (1) allocated to each other in pairs, each beam deflector being controllable such that it deflects the light beam (9) directed thereto into a selectable direction in order for the beam to enter at least one selected terminal end (55).

Abstract: An etalon has a first surface which is partially reflective. The reflectivity of the first surface varies with position. Thus, this reflectivity can in effect be adjusted by varying the point at which an optical beam is incident upon the etalon. At one point of incidence, the optical beam experiences one reflectivity. At a different point of incidence, the optical beam experiences a different reflectivity.

Abstract: A device for filtering at least a predetermined selected optical signal having a predetermined wavelength range from a series of optical signals, the device comprising: a polarisation alignment means for substantially aligning substantially orthogonal polarisation states of an optical input signal so as to produce a polarisation aligned optical signal; a polarisation manipulation means for imparting a controlled polarisation manipulation to the polarisation aligned optical signal so as to output a polarisation manipulated optical signal having one of at least two distinguishable polarisation states including a first polarisation state and a second polarisation state; and an optical separation means for spatially separating the selected optical signal from the series of optical signals when the polarisation state of the polarisation manipulated optical signal is in a first polarisation state, thereby forming a first and second output optical signal, and maintaining the spatial alignment of the selected optical

Abstract: An etalon stage includes separate fibers that are used as input and output ports to an etalon. An optical system located between the fibers and the etalon couples light from the input fiber to the etalon to the output fiber.

Abstract: An etalon includes a tuning plate in the air-gap between the etalon mirrors. The method of tuning includes selecting a tuning plate that makes the optical length of the etalon slightly less than required for ITU and then rotating the tuning plate through a small angle until tuning is complete. The tuning plate material is selected to provide dispersion compensation and to compensate for thermal expansion of the mirror spacers.

Abstract: A multiplexing device includes two facing-but-spaced apart optical transmitting plates, with optical reflective filters in facing contact with outer surfaces of the optical transmitting plates to define a reflective beam path therebetween. Light transceivers are associated with each of the optical reflective filters. The optical transmitting plates have greater indices of refraction than the central medium between them, so that the beam path has a low angle of incidence to the optical reflective filters but a higher angle in the central medium.

Abstract: A system and method for guiding a beam of electromagnetic radiation is disclosed. The system includes at least a first stack of dielectric layers, the first stack comprising at least a first substack, a second substack and a third substack, the third substack separating said first and second substack, the first substack comprising at least one dielectric layer, the second substack comprises at least one dielectric layer, the third substack comprises at least one dielectric layer. The dielectric layers of the first substack and the second substack equidistant from the third substack have the same refractive index.

Abstract: An etalon comprising at least one transparent plate, wherein the transparent plate consists of lithium tantalate single crystal, an etalon comprising at least one transparent plate, wherein the transparent plate consists of lithium niobate single crystal and a method for producing an etalon, which comprises 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 DWDM thin film filter includes a substrate (11) and a film stack (12). The film stack comprises a plurality of cavities (13). Each cavity includes a first group of mirror layers (21), a second group of mirror layers (22), and a spacer layer (23). Each group of mirror layers includes a plurality of high refractive index thin films (31) and low refractive index thin films (32) alternately deposited one on another. The material of the high refractive index films is a composition of indium-tin oxide. In the preferred embodiment, a thin film filter having 160 layers of film can be produced. Such a thin film filter attains the same or better optical characteristics as a conventional DWDM thin film filter having 180 layers of film.

Abstract: Optical systems for producing modulated light are provided. A representative optical system incorporates an electron emitter and a electrical-to-optical converter. The electron emitter is operative to produce electrons. The electrical-to-optical converter is operative to receive electrons and convert the electrons into light. The optical system modulates the light so that modulated light is emitted. Methods and other optical systems also are provided.

Abstract: A nonlinear optical chromophore having the formula D-&pgr;-A, wherein &pgr; is a &pgr; bridge including a thiophene ring having oxygen atoms bonded directly to the 3 and 4 positions of the thiophene ring, D is a donor, and A is an acceptor.

Abstract: A system for wavelength locking i.e. for maintaining a frequency of an optical signal to within predetermined limits has means for splitting part of the controlled optical signal into at least three sub-beams of which one is a reference beam and two others are provided to an optical element having a periodic output response and to a filter having a monotonic output response. The three detected outputs are analyzed and processed to determine accurately the wavelength of the optical signal and to produce a correcting signal if it is not within the predetermined limits.

Abstract: Light in the visible spectrum is modulated using an array of modulation elements, and control circuitry connected to the array for controlling each of the modulation elements independently, each of the modulation elements having a surface which is caused to exhibit a predetermined impedance characteristic to particular frequencies of light. The amplitude of light delivered by each of the modulation elements is controlled independently by pulse code modulation. Each modulation element has a deformable portion held under tensile stress, and the control circuitry controls the deformation of the deformable portion. Each deformable element has a deformation mechanism and an optical portion, the deformation mechanism and the optical portion independently imparting to the element respectively a controlled deformation characteristic and a controlled modulation characteristic. The deformable modulation element may be a non-metal.

Abstract: A device is provided for generating a photonic signal having a phase different from an input photonic signal that is incident on the device. The input photonic signal has an signal frequency, signal bandwidth, and a signal intensity. The device comprises a plurality of material layers. The material layers are arranged such that the device exhibits a photonic band gap structure. The photonic band gap structure exhibits a transmission band edge that corresponds to the input photonic signal frequency. A second photonic signal is generated at a second photonic frequency preferably close to a second band edge. The interaction of the input photonic signal with the second photonic signal generates a phase shift of order &pgr; for relatively small input intensities.

Abstract: A solid state device used to modulate the intensity of reflected or transmitted light by modulating with an external voltage the optical thickness of a thin film ferroelectric placed in an etalon cavity is disclosed. The device is constructed by selecting a generally planar supporting substrate, preferably silicon or sapphire in order to be compatible with silicon integrated circuits. A dielectric stack consisting of alternating layers of different index of refraction materials, also specifically selected to be compatible with later growth of the thin film ferroelectric, is deposited thereon to form a partially reflective and partially transmitting mirror, followed by a transparent electrically conductive layer. The thin film ferroelectric is deposited on the conductive layer, followed by a second transparent conductive layer and a second dielectric stack. Leads are connected to the conductive layers and in turn to a voltage generator.

Abstract: An interference modulator (Imod) incorporates anti-reflection coatings and/or micro-fabricated supplemental lighting sources. An efficient drive scheme is provided for matrix addressed arrays of IMods or other micromechanical devices. An improved color scheme provides greater flexibility. Electronic hardware can be field reconfigured to accommodate different display formats and/or application functions. An IMod's electromechanical behavior can be decoupled from its optical behavior. An improved actuation means is provided, some one of which may be hidden from view. An IMod or IMod array is fabricated and used in conjunction with a MEMS switch or switch array. An IMod can be used for optical switching and modulation. Some IMods incorporate 2-D and 3-D photonic structures. A variety of applications for the modulation of light are discussed. A MEMS manufacturing and packaging approach is provided based on a continuous web fed process.

Abstract: This invention relates to invention relates to a variable slope optical filter in the form of a Fabry-Perôt etalon having an end face with a variable finesse. A method for filtering and a variable slope optical filter for in-line use with an optical amplifier signal is also disclosed. The filter has a wavelength response that is substantially linear in slope within a band of operation wavelengths of the amplifier; the slope of the filter in an operating band of wavelengths is between zero and a only one of a positive or negative number; furthermore the filter has an amplitude response that has an opposite and counter slope as a function of wavelength to that of a gain tilt of the amplifier within the operation band of wavelengths. Relative movement between the filter and the optical amplifier signal is provided to vary the slope of the filter by means of varying the amplitude wavelength response of the filter.

Abstract: An apparatus and method of chromatic dispersion includes the negative compensation per channel filter (130) coupled to an optical receiving path (100) for providing a lossless discontinuous per-channel dispersion compensation in the optical receiving path (100). The optical receiving path (100) includes an input port (131), at the input of the filter (130), for receiving an input optical pulse (120) having a packet of waves at corresponding frequencies transmitted and received by an optical fiber (115).

Abstract: A Virtually Imaged Phased Array (VIPA) contains a separate, precision-machined optical surface that forms one surface of the internal etalon and a boundary of the “radiation window,” in order to more easily achieve the optical-mechanical tolerances necessary for desired performance. VIPA design known to the prior art requires that a high reflective (mirror) optical coating be applied to a portion of a face of a plate of glass with a very sharp and well controlled boundary line across the surface while the remainder has an AR coating. This is difficult under the state of the art. In the disclosed VIPA, the required sharp boundary can be the machined physical edge of a plate of material (instead of the edge of a coating), which can be very precisely cut and controlled using common optical techniques. The disclosed VIPA is more easily manufactured than those known to the state of the art, and therefore is practical for applications such as the dispersing element in a chromatic dispersion compensator.

Abstract: The invention is related to an optical device comprising, in an housing (1) with a defined gas atmosphere:

Abstract: An improved stepped etalon comprises a transparent body having a stepped surface. The lands of the steps are separated by a non-abrupt or softened transition region. This reduces the diffraction of light caused by the step transitions, thereby reducing the dead spot behind the step transition portions where interference prevents accurate measurements of light transmission from being made. Methods for producing a smoothly stepped etalon and for smoothing the step transitions in an abruptly stepped etalon are also disclosed.

Abstract: An optical signal regenerator includes a mechanism for reconstituting an optical signal carrier wave. The optical signal is thus regenerated on the same wavelength as the incoming carrier wave.

Abstract: A multi-cavity optical device allowing selective control of a bandpass characteristic thereof . Fabry-Perot structures are coherently coupled together to form a narrow bandpass structure. At least one of the spacer regions in the device includes an active material that changes the optical thickness of the spacer to de-tune the device. In one embodiment, the active material is transparent and lies along the optical path through the device. In another embodiment, an active material that lies outside of the optical path tunes an air gap. Altering the first or last spacer in a multi-cavity structure provides variation in the transmission loss while generally retaining a flattop filter response with low passband ripple. Altering interior spacer regions provides high sensitivity to variations in the optical thickness of the spacer.

Abstract: A process for configuring a tunable MOEMS filter train comprises determining a spectral response of a MOEMS tunable filter. A spectral separation between different order modes, or free spectral range, is then determined for the filter. This information is then related to a mode size of a desired mode of the tunable filter. With this information, lenses for the optical train are provisioned, and then installed so that light is launched into the optical filter at the desired mode size to thereby maximize the SMSR of the filter train.

Abstract: A process for configuring a tunable MOEMS filter train comprises determining a spectral response of a MOEMS tunable filter. A spectral separation between different order modes, or free spectral range, is then determined for the filter. This information is then related to a mode size of a desired mode of the tunable filter. With this information, lenses for the optical train are provisioned, and then installed so that light is launched into the optical filter at the desired mode size to thereby maximize the SMSR of the filter train.

Abstract: The thermo-optic behavior of an optical path over a range of temperatures &Dgr;T is controlled by determining a figure-of-merit (FOM) for the optical path and including in the path a body of crystalline material that enables the conditions specified by the FOM to be satisfied. The crystalline material is highly transparent at a wavelength &lgr; of radiation propagating in the path, and it has a coefficient of thermal expansion (CTE) and a refractive index n such that the CTE and dn/dT are mutually adapted to satisfy the FOM over the range &Dgr;T. In one embodiment, the CTE and dn/dT of an etalon compensate one another so as to perform frequency discrimination that is essentially temperature insensitive over the range &Dgr;T. In a preferred embodiment of the optical etalon the crystalline material comprises LiCaAlF6.

Abstract: Among other things, a cavity having a cavity dimension is configured so that the cavity dimension changes in response to electrostatic forces applied to the cavity, and at least two electrical structures are configured to apply electrostatic forces in the vicinity of the cavity, the electrical structures being independently controllable.

Abstract: A solid state device used to modulate the intensity of reflected or transmitted light by modulating with an external voltage the optical thickness of a thin film ferroelectric placed in an etalon cavity is disclosed. The device is constructed by selecting a generally planar supporting substrate, preferably silicon or sapphire in order to be compatible with silicon integrated circuits. A dielectric stack consisting of alternating layers of different index of refraction materials, also specifically selected to be compatible with later growth of the thin film ferroelectric, is deposited thereon to form a partially reflective and partially transmitting mirror, followed by a transparent electrically conductive layer. The thin film ferroelectric is deposited on the conductive layer, followed by a second transparent conductive layer and a second dielectric stack. Leads are connected to the conductive layers and in turn to a voltage generator.

Abstract: An optical waveguide format tuneable optical filter is formed using Bragg grating reflectors to define one or more optical cavities of a Fabry Pérot etalon, the or each cavity of the etalon including one or more slots containing a controllable refractive index medium, for instance a silicone gel whose index is regulated by Joule heating, or a polymer dispersed liquid crystal whose index is electric field regulated. Strong coupling coefficient (˜ a few tens mm−1) gratings may be made using lithography to form linear arrays of buried high index inclusions extending along the waveguide core axis.

Abstract: The present invention provides in one aspect, a method of controlling a SLM comprising the following steps: providing a sequential color SLM controller, and a SLM; providing a means whereby said sequential color SLM controller loads optimum values for a single color into control registers of said SLM, during all the field time slots of each video frame; also causing said SLM to modulate light of said single color, during said field time slots of each video frame, whereby the duty cycle for display of said color is increased relative to operation in a normal sequential color mode.

Abstract: There are provided an optical element which can reduce an assembly cost by simplifying focus adjustment of the optical element, decreasing the number of parts required for the adjustment, and shortening the adjustment time, and an optical scanning device using the element. The optical element has a plurality of sets of positioning references for defining the position of the element in the optical axis direction. The plurality of sets of positioning references respectively define different positions in the optical axis direction.

Abstract: A solid state device used to modulate the intensity of reflected or transmitted light by modulating with an external voltage the optical thickness of a thin film ferroelectric placed in an etalon cavity is disclosed. The device is constructed by selecting a generally planar supporting substrate, preferably silicon or sapphire in order to be compatible with silicon integrated circuits. A dielectric stack consisting of alternating layers of different index of refraction materials, also specifically selected to be compatible with later growth of the thin film ferroelectric, is deposited thereon to form a partially reflective and partially transmitting mirror, followed by a transparent electrically conductive layer. The thin film ferroelectric is deposited on the conductive layer, followed by a second transparent conductive layer and a second dielectric stack. Leads are connected to the conductive layers and in turn to a voltage generator.

Abstract: An etalon filter of the invention is an etalon filter where the light transmission property depending on temperature is reduced, which is preferable as an optical device. An etalon filter (11) has a filter main body (1) where reflecting films are disposed on a light input side surface and a light output side surface of a light transmission medium. The etalon filter (11) is formed by disposing different linear expansion coefficient members (2) having a coefficient of linear expansion different from that of the light transmission medium in areas on both sides of the filter main body (1) except optical path length areas (4).

Abstract: A tunable optical cavity constructed from a fixed mirror and a movable mirror. The fixed mirror is attached to a substrate having a first electrically conducting surface. A support member having the moveable mirror supported thereon and having a second electrically conducting surface, is suspended above the substrate. A circuit applies an electrical potential between the first and second electrically conducting surfaces thereby adjusting the distance between the fixed and movable mirrors. The fixed mirror and the moveable mirror are positioned such that the mirrors form the opposite ends of the optical cavity. The distance between the fixed mirror and the moveable mirror is a function of the applied electrical potential. The fixed mirror is mounted in a well in the substrate such that distance between the support member and the substrate is less than half the distance between the mirrors.