Abstract: An optical repeater formed in an optical passive component passively relays an incoming multiplexed optical signal. The repeater has an optical decoder decoding the multiplexed optical signal, and an optical encoder encoding an optical signal from a termination unit connected to the repeater. The repeater further includes a first optical path switch outputting an incoming multiplexed optical signal to the optical decoder and outputting the optical signal delivered from the optical decoder, a second optical path switch outputting the optical signal coming from the first optical path switch to the termination unit, and a third optical path switch outputting the optical signal coming from the second optical path switch to the encoder and outputting the optical signal delivered from the encoder.

Abstract: Disclosed is a bidirectional optical transceiver module having an efficient optical coupling structure. The bidirectional optical transceiver module according to an exemplary embodiment of the present disclosure includes a first structure which has a hexahedron shape, has four side surfaces of which two side surfaces are formed to be inclined at a predetermined angle with respect to a bottom surface, and is transparent to both a transmitted light component and a received light component; and at least one second structure which has a planar shape, is inserted in the first structure so as to form a right angle with the bottom surface of the first structure and be tilted by a predetermined angle from a direction of the transmitted light component or the received light component, and is transparent to one of the transmitted light component and the received light component and reflective of the other one.

Abstract: A wavelength selective optical switch includes an incidence/emergence unit that includes an input port at which signal light made up of light of numerous wavelengths is incident and an output port at which light signals of selected wavelengths are emergent, a wavelength dispersion element that spatially disperses signal light according to a wavelength of the signal light, and synthesizes reflected light, a condenser element that condenses light dispersed by the wavelength dispersion element on a two-dimensional plane, a space phase modulator arranged so as to receive incident light deployed on an xy plane made up of an x-axis direction deployed according to wavelength and a y-axis direction orthogonal to the x-axis direction, and having numerous pixels arranged in a lattice on the xy plane, and a space phase modulator drive unit.

Abstract: Embodiments of the present invention are directed to implementing high-radix switch topologies on relatively lower-radix physical networks. In one embodiment, the method comprises constructing the physical network (702) composed of one or more optical switches connected via one or more waveguides. A desired switch topology (704) is then designed for implementation on the physical network. The switch topology is then overlain on the switch network by configuring the optical switches and waveguides (706) to implement the switch topology on the physical network. The optical switches can be reconfigured following a transmission over the physical network and can be configured to implement circuit switching or packet switch.

Abstract: A multi-chip module (MCM) includes a stack of chips that are coupled using optical interconnects. On a first surface of a middle chip in the stack, there are: a first optical coupler, an optical waveguide, which is coupled to the first optical coupler, and a second optical coupler, which is coupled to the optical waveguide. The first optical coupler redirects an optical signal from the optical waveguide to a first direction (which is not in the plane of the first surface), or from the first direction to the optical waveguide. The second optical coupler redirects the optical signal from the optical waveguide to a second direction (which is not in the plane of the first surface), or from the second direction to the optical waveguide. An optical path associated with the second direction passes through an opening in a substrate in the middle chip.

Abstract: An optical connector having a plurality of directional taps and connecting between a plurality of optical waveguides (e.g., such as a connector between a waveguide that is part of, or leads from, a seed laser and/or an initial optical-gain-fiber power amplifier, and a waveguide that is part of, or leads to, an output optical-gain-fiber power amplifier and/or a delivery fiber), wherein one of the directional taps extracts a small amount of the forward-traveling optical output signal from the seed laser or initial power amplifier (wherein this forward-tapped signal is optionally monitored using a sensor for the forward-tapped signal), and wherein another of the directional taps extracts at least some of any backward-traveling optical signal that may have been reflected (wherein this backward-tapped signal is optionally monitored using a sensor for the backward-tapped signal).

Abstract: Methods of operating an optical circuit switch and optical circuit switches are disclosed. An optical circuit switch may receive a first make command to make a first optical connection between a first port and a second port, the first port uniquely associated with a rotatable mirror element, determine a first baseline voltage to be applied to an electrode coupled to the mirror element to cause the mirror element to rotate about an axis to make the first optical connection, and apply the first baseline voltage to the electrode. The optical circuit switch may periodically adjust the voltage applied to the electrode to minimize an insertion loss of the first optical connection, and periodically store accumulated angular drift data in a memory, the accumulated angular drift data derived from a difference between the adjusted voltage applied to the first electrode and the first baseline voltage.

Abstract: An optical module manufacturing method includes: forming a first waveguide layer and a second waveguide layer on a first substrate and a second substrate respectively, or forming a first waveguide layer and a second waveguide layer on a first surface of a first substrate and a second surface of the first substrate respectively; disposing the first substrate on the second substrate; disposing a filter at an end of the first waveguide layer and the second waveguide layer, so that the filter is aligned with the second waveguide layer; and disposing a prism on the filter, so that a first reflective surface of the prism is aligned with the first waveguide layer, and a second reflective surface is aligned with the second waveguide layer. Embodiments of the present application further disclose an optical module.

Abstract: A multi-chassis network device includes a plurality of nodes that operate as a single device within the network and a switch fabric that forwards data plane packets between the plurality of nodes. The switch fabric includes a set of multiplexed optical interconnects coupling the nodes. For example, a multi-chassis router includes a plurality of routing nodes that operate as a single router within a network and a switch fabric that forwards packets between the plurality of routing nodes. The switch fabric includes at least one multiplexed optical interconnect coupling the routing nodes. The nodes of the multi-chassis router may direct portions of the optical signal over the multiplexed optical interconnect to different each other using wave-division multiplexing.

Abstract: A light-shielding portion (10) shields the light spot of output light output toward a shunt position ? by a projecting portion (12). Hence, the output light output toward the shunt position ? does not travel to an output port (111). This allows to prevent crosstalk.

Abstract: An optical switching system is disclosed. The system comprises: input optics, for receiving light from at least one input optical port and separating the light into a plurality of optical channels to assign a separate optical path to each channel of each input optical port. The system further comprises an input steering array and an output steering array arranged such that the input steering array is imaged onto the output steering array, wherein the input steering array is configured to receive the separated light and steer each optical channel to an individual element of the output steering array. The system further comprises output optics, for receiving the optical channels from the output steering array and coupling the optical channels into at least one output optical port.

Abstract: An opto-mechanical switch produces different optical paths from two optical path sections out of a plurality of optical path sections that are oriented in different spatial directions. The switch has an optical component on which one end of each optical path section impinges, and which is adapted to be moved linearly in a direction of movement at right angles to the optical path sections between different switching positions, in which it selectively couples different optical path sections optically with each other. Further provided is a measuring system for the analysis of fluids, having such an opto-mechanical switch.

Abstract: An optical arrangement includes an actuatable optical element and a compensating optical element. The actuatable optical element is provided to receive an optical beam having a plurality of spatially separated wavelength components and diffract the plurality of wavelength components in a wavelength dependent manner. The compensating optical element directs the optical beam to the actuatable optical element. The compensating optical element compensates for the wavelength dependent manner in which the wavelength components are diffracted by the actuatable optical element.

Abstract: Methods of operating an optical circuit switch and optical circuit switches are disclosed. A command to make an optical connection between a first port and a second port may be received, the first port uniquely associated with a first rotatable mirror element and the second port uniquely associated with a second rotatable mirror element. A determination whether or not input signal light is present at the first port may be made. When light is present at the first port, the first mirror element and the second mirror may be rotated to provide an initial optical connection between the first port and the second port. When light is not present at the first port, the first mirror element and the second mirror element may be placed in respective at-rest positions.

Abstract: Techniques are presented for illuminating an optically activated switch. The switch is illuminated from one side with a high reflector on the opposing side. An anti-reflective coating can also be formed on the side from which the illumination is incident. For more uniform illumination, a homogenizer, such as a micro-lens array, can be used. Illumination can be provided from an array of micro-fibers, which can be set back by a few millimeters from the switch. In another set of example, a light pipe arrangement can be used to provide the illumination. The light pipe structure can also act as a beam splitter.

Abstract: Techniques are presented for illuminating an optically activated switch. The switch is illuminated from one side with a high reflector on the opposing side. An anti-reflective coating can also be formed on the side from which the illumination is incident. For more uniform illumination, a homogenizer, such as a micro-lens array, can be used. Illumination can be provided from an array of micro-fibers, which can be set back by a few millimeters from the switch.

Abstract: A waveguide intersection includes an input waveguide and an output waveguide; a crossing waveguide intersecting the input waveguide and the output waveguide to form an intersection; and a block that is optically joined to the intersection such that a guided mode is produced within the intersection. A method of reducing optical losses within a waveguide intersection includes increasing a cross-sectional height of an intersection such that optical energy passing through the intersection is laterally confined.

Abstract: An optical interconnect (200) includes: a reflective body (230) having a first reflective surface (235) and a second reflective surface (240) opposite the first reflective surface (235); a first optical waveguide (205) that directs a first optical signal received from a first communicating device (105) to the first reflective surface (235); a second optical waveguide (210) that directs the first optical signal from the first reflective surface (235) of the reflective body (230) to a second communicating device (110); a third optical waveguide (215) that directs a second optical signal received from the second communicating device (110) to the second reflective surface (240) of the reflective body (230); and a fourth optical waveguide (220) that directs the second optical signal from the second reflective surface (240) of the reflective body (230) to the first communicating device (105).

Abstract: A wavelength-selective optical switch for switching arbitrary wavelengths between optical fibers in mesh networks, using interference filters for separating optical wavelengths, and two-dimensional arrays of micromirrors for switching. Broadband switch inputs and outputs are provided for adding and dropping arbitrary wavelengths at each node of the network. A two-stage multiplexer and two-stage demultiplexer are provided to simplify the free-space demultiplexer and multiplexer. Mechanisms are provided that allows full non-blocking functionality in the presence of finite yield of the micromirror arrays.

Abstract: An optical assembly for a wavelength-division-multiplexing (WDM) transmitter or receiver that lends itself to cost-effective production-line manufacturing. In one embodiment, the fiber optic assembly has a vernier-type arrayed waveguide grating (AWG) with five optical ports at one side and fourteen optical ports at another side. Ten of the fourteen ports are optically coupled to ten photo-detectors or lasers. A selected one of the five ports is optically coupled to an external optical fiber. The coupling optics and the mounting hardware for the AWG are designed to accommodate, with few relatively straightforward adjustments performed on the production line, any configuration of the AWG in which any consecutive ten of the fourteen ports are optically coupled to the ten photo-detectors or lasers.

Abstract: Provided is a wavelength selective switch which includes: at least one input port; a dispersive portion for dispersing wavelength-multiplexed light input from the input port into wavelength-demultiplexed lights; a condenser element for condensing the wavelength-demultiplexed lights dispersed by the dispersive portion; a deflection portion having deflection elements for deflecting, for each wavelength-demultiplexed light condensed by the condenser element; at least one output port for outputting the wavelength-demultiplexed lights deflected by the deflection portion. A light-condensing position shift compensating element is disposed in an optical path between the input port and the dispersive portion or in the dispersive portion, for compensating light-condensing position shift of the wavelength-demultiplexed lights relative to the deflection element, light-condensing position shift being generated based on the arrangement of the input ports.

Abstract: A multi-dimensional data registration integrated circuit is configured for driving array-arrangement devices. The array-arrangement devices comprise a plurality of first hierarchy sets, each which comprises a plurality of second hierarchy sets. The multi-dimensional data registration integrated circuit comprises a first hierarchy address selection circuit, a second hierarchy address selection circuit and a data supply circuit. The first hierarchy address selection circuit scans the first hierarchy sets, and selects a unit of the first hierarchy sets to activate it. The second hierarchy address selection circuit scans the second hierarchy sets. The data supply circuit writes a plurality of data into each designated unit of the second hierarchy sets according to the scanning sequence of the second hierarchy address selection circuit.

Abstract: A wavelength division multiplexer/demultiplexer includes an optical block having a plurality of protrusions positioned at a first side, wherein at least one of the protrusions has a first inclined plane configured to reflect a light propagating in the optical block to a second inclined plane of the protrusion. Another wavelength division multiplexer/demultiplexer includes an optical block having a first side, a plurality of depressions indented from the first side, wherein at least one of the depressions has a first inclined plane configured to reflect a light to a second side and a second inclined plane configured to reflect the light from the second side.

Abstract: The present invention provides a WDM which includes three ports, the three ports each include an optical fiber array and a micro lens array matching the optical fiber array; an optical signal is transmitted to a filter after passing through a corresponding micro lens in a first micro lens array of the common port; transmitted light of the optical signal enters a corresponding micro lens in a second micro lens array of the pass port after passing through the filter, and then the light is output by a corresponding optical fiber in a second optical fiber array of the pass port; reflected light of the optical signal enters a corresponding micro lens in a third micro lens array of the reflection port after being reflected by the filter, and the light is output by a corresponding optical fiber in a third optical fiber array of the reflection port.

Abstract: Provided are an optical switch device having a simple light path and capable of achieving high speed switching, and a method of manufacturing the optical switch device. The optical switch device comprises one or more first optical waveguides extending in a first direction, one or more second optical waveguides connected to the first optical waveguides in a second direction crossing the first direction, and one or more switching parts configured to control light transmitted in the first direction within the first optical waveguide connected with the second waveguide, to selectively reflect the light to the second waveguide extending in the second direction.

Abstract: An optical switch system and the system includes a semi-transmissive semi-reflective module is configured to intercept, in a transmission manner, test light that is the same as the signal light with respect to the propagation path and output after being modulated by the optical output control module; the imaging module is configured to acquire the test light, generate corresponding initial optical path information and sampled optical path information in sequence, and transfer the initial optical path information and the sampled optical path information to the judging module in sequence; the judging module is configured to record the initial optical path information, and compare the sampled optical path information with the initial optical path information; and the control module is configured to control the optical output control module according to a comparison result.

Abstract: Optical switches can include collimator elements that accommodate two or more optical ports. This increases the number of ports the switch can accommodate without having to increase the size of other optical components within the switch. Separate deflectors can be used to accommodate optical signals from two different groups of ports. In some embodiments cross-coupling of signals between the two groups can be accomplished through use of re-direction optics.

Abstract: The present disclosure includes apparatus, system, and method embodiments that provide micro electro mechanical system optical switching and methods of manufacturing switches. For example, one optical switch embodiment includes at least one micro electro mechanical system type pivot mirror structure disposed along a path of an optical signal, the structure having a mirror and an actuator, and the mirror having a pivot axis along a first edge and having a second edge rotatable with respect to the pivot axis, the mirror being capable of and arranged to be actuated to pivot between a position parallel to a plane of an optical signal and a position substantially normal to the plane of the optical signal.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: A wavelength selective switch includes a substrate. On the substrate, the wavelength selective switch includes at least one input port, a dispersive element, a light converging element, a light deflecting member, an output port, and a driving mechanism which drives at least one of the dispersive element, the light condenser element, and the light deflecting member, and drive by the driving mechanism is a rotational drive around an axis perpendicular to the substrate, for the dispersive element, and is a translational drive in a direction of dispersion of wavelength with respect to the substrate, for the light condenser element or the light deflecting member.

Abstract: Systems, methods, and apparatus to route optical signals are disclosed. An example apparatus to route optical signals includes a plurality of hollow metal waveguide optical switch arrays, the arrays being stacked, each of the arrays including: a first number of optical input ports; and a second number of optical output ports different than the first number of input ports.

Abstract: An optical device may include a substrate and an optical waveguide carried by the substrate and having a notch therein defining a feed optical waveguide and a longitudinal optical waveguide section on opposite longitudinal sides of the notch. The optical device may also include a transverse optical waveguide section carried by the substrate and transversely aligned with the feed optical waveguide adjacent the notch. The optical device may further include an elastomeric waveguide switch body configured to be moved between a first position within the notch and operative to switch light from the feed optical waveguide to the longitudinal optical waveguide section, and a second position removed from the notch and operative to switch light from the optical waveguide to the transverse optical waveguide section.

Abstract: An optical switch includes: a semiconductor substrate, including a first rotation part and a first torsion beam disposed at two ends of the first rotation part, where the first torsion beam is configured to drive the first rotation part to rotate; a microreflector, disposed on a surface of the first rotation part of the semiconductor substrate; a first latching structure, disposed on a surface of the first torsion beam, the first latching structure including a form self remolding (FSR) material layer and a thermal field source, where the thermal field source is configured to provide a thermal field for the FSR material layer and the FSR material layer is configured to undergo form remolding under the thermal field, so as to latch the first rotation part and the microreflector in a position after rotation.

Abstract: Techniques for designing optical devices that can be manufactured in volume are disclosed. In an exemplary an optical assembly, to ensure that all collimators are on one side to facilitate efficient packaging, all collimators are positioned on both sides of a substrate. Thus one or more beam folding components are used to fold a light beam up and down through the collimators on top of the substrate and bottom of the substrate.

Abstract: An optical interconnect includes a set of splitters. Each splitter includes a source waveguide, a reflection waveguide, an output waveguide, and a partially reflective mirror element with a reflective coating. The source waveguide and the reflection waveguide are optically coupled to the partially reflective element. A photonic signal from the source waveguide is partially reflected off the reflective coating as a reflected signal into the reflection waveguide. The output waveguide is optically coupled to the opposite surface and configured such that a non-reflected portion of the photonic signal propagates into the output waveguide. The reflective coating includes a reflected surface area interfacing with the photonic signal form the source waveguide, and power of the non-reflected portion is a function of the reflective surface area interfacing with source waveguide.

Abstract: The invention concerns a method for generating a laser beam (3) with different beam profile characteristics, whereby a laser beam (2) is coupled into one fibre end (1a) of a multi-clad fibre (1), in particular a double-clad fibre, and emitted from the other fibre end (1b) of the multi-clad fibre (1) and whereby, to generate different beam profile characteristics of the output laser beam (3), the input laser beam (2) is electively coupled either at least into the inner fibre core (4) of the multi-clad fibre (1) or at least into at least one outer ring core (6) of the multi-clad fibre (1), as well as a corresponding arrangement (10).

Abstract: The present invention relates to a total reflection type optical switch using polymer insertion type silica optical waveguides and a manufacturing method thereof. The total reflection type optical switch forms a trench in an intersecting point of the silica optical waveguides having two optic routes, and inserts a polymer into the trench. A total reflection type optical switch has a heater which heats the polymer. The polymer is made of thermo-optic material, and totally reflects an optical signal as a refraction index falls when heated by the heater. In addition, when not heated by the heater, the polymer transilluminates the optical signal. When the polymer is made of electric-optic material, the total reflection type optical switch may have upper and lower electrodes for applying an electric field in the polymer instead of the heater.

Abstract: An example embodiment of the present invention is a non-blocking wavelength switching architecture that enables graceful scaling of a network wavelength switching node from small to large fiber counts using fixed size bidirectional 1×N Wavelength Selective Switches (WSS). The architecture uses an intermediate broadcast and select layer implemented using optical splitters and WSSs to eliminate wavelength blocking.

Abstract: To provide a waveguide type wavelength domain optical switch which makes it possible to use a cheap lens, makes it possible to correct aberration of the demultiplexed wavelengths produced in a plurality of waveguide type demultiplexing circuits, a wavelength domain optical switch is provided with: an integrated element formed by laminating three or more waveguide type demultiplexing circuits; a first lens for collecting light emitted from the integrated element; a polarization separation element for separating light emitted from the first lens into X polarization and Y polarization and emitting the X polarization and the Y polarization at different angles; a second lens for collecting the X polarization and the Y polarization; a first reflective optical phase modulator for reflecting the collected X polarization and Y polarization at any angles; a ½-wavelength plate disposed between the second lens and the first reflective optical phase modulator in order to make polarization directions of the X polarization

Abstract: A variable optical attenuator device is described that comprises a first optical input, a first optical output, a first optical path between the first optical input and the first optical output, and means for moving a shutter across said first optical path. A hollow core waveguide is provided to substantially guide light along the first optical path of the device. The device may also be used to provide an analogue beam splitting or switch function in telecommunication systems and the like.

Abstract: An innovative micro-size photonic switch is presented. The photonic switch is comprised of: a mirror having a reflecting surface; an input waveguide; and an output tapered waveguide structure. The photonic switch further includes a switching mechanism disposed adjacent to the reflecting surface and operable to change the refractive index along the reflective surface and thereby shift the angle at which the optical signal reflects from the mirror. More specifically, the switching mechanism may operate to change concentration of free carrier distribution along the reflective surface and thereby displace the effective reflecting interface of the mirror. In this way, the optical signal can be directed to one of two or more output ports of the output tapered waveguide structure and finally exited by one output waveguide channel that is connected to the selected port of the output tapered waveguide structure.

Abstract: Optical systems for routing light that reduce or eliminate polarization-dependent loss are provided. Such optical systems generally accommodate an optical element that has an intrinsic polarization-dependent loss and which is disposed to be encountered twice by the light being routed. In some instances, the optical element may be a dispersive element such as a diffraction grating or prism, but the invention has more general applicability. The optical system additionally includes both a reflective element and a wave plate assembly disposed to be encountered by the light between encounters with the dispersive element.

Abstract: The present disclosure provides optimized configurations for a directionless reconfigurable optical add/drop multiplexer application. The present invention includes an add module with improved optical signal-to-noise through placing amplifiers prior to a multi-cast optical switch. The present invention includes various drop module configurations utilizing distributed gain, channel selective filters, and bi-directional configurations to reduce power consumption and complexity. Additionally, the present invention includes an integrated broadcast and select architecture.

Abstract: A method and apparatus are provided for attenuating an optical beam. The method includes selecting a level of attenuation to be applied to the optical beam. A pattern of on-state and off-state pixels in a two dimensional spatial light modulator (SLM) is selected such that the pattern will modulate the optical beam to provide the selected level of attenuation. Finally, the optical beam is directed onto the SLM while tile pixels are arranged in the selected pattern. The pattern is periodic along a first axis and symmetric along a second axis along which an intensity distribution of die optical beam extends.

Abstract: In fabricating an optical I/O array module, an optical waveguide provided with mirror parts, each having a tapered face, is formed on a substrate, a convex shaped member or a concave shaped member is placed at spots above the respective mirror parts of the optical waveguide, and laser diode arrays and photo diode arrays, provided with either a concave shape, or a convex shape, are mated with, or into the convex shaped member or the concave shaped member before being mounted. Further, there are formed multiple filmy layers, on which an LSI where a driver IC LSI of optical elements, and an amplifier LSI of the optical elements are integrated.

Abstract: Embodiments relate to silicon optical line multiplexers. In an embodiment, an optical line multiplexer includes at least one microprism etched from a silicon substrate. Another embodiment includes a plurality of these microprisms forming an array. In use, a light beam is guided through the multiplexer device such that it impinges on a line of microprisms that, depending upon their orientation, either reflect/deflect or transmit the beam.

Abstract: A micro-structure produced by utilizing a MEMS technology or the like includes: a frame including a portion having a first layer and a portion having a second layer on the lower side of the first layer; a movable body including a portion having the first layer and a portion having the second layer; and at least one swing supporting portion which is having the first layer, and connects the portion having the first layer in the frame and the portion having the first layer in the movable body, to support the movable body to be capable of swinging. A frame side end portion of the swing supporting portion is supported from underneath by the portion having the second layer in the frame, and a movable body side end portion of the swing supporting portion is supported from underneath by the portion having the second layer in the movable body.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: A multi-chassis network device includes a plurality of nodes that operate as a single device within the network and a switch fabric that forwards data plane packets between the plurality of nodes. The switch fabric includes a set of multiplexed optical interconnects coupling the nodes. For example, a multi-chassis router includes a plurality of routing nodes that operate as a single router within a network and a switch fabric that forwards packets between the plurality of routing nodes. The switch fabric includes at least one multiplexed optical interconnect coupling the routing nodes. The nodes of the multi-chassis router may direct portions of the optical signal over the multiplexed optical interconnect to different each other using wave-division multiplexing.

Abstract: A method of manufacturing a tunable wavelength optical filter. The method includes steps of forming a first sacrificial oxide film for floating a lower mirror on a semiconductor substrate; sequentially laminating conductive silicon films and oxide films for defining a mirror region on the first sacrificial oxide film in a multi-layer and laminating another conductive silicon film to form a lower mirror; sequentially laminating conductive silicon films and oxide films for defining the mirror region on a second sacrificial oxide film in a multi-layer and laminating another conductive silicon film to form an upper mirror and forming an optical tuning space between the lower mirror and the upper mirror and etching the first sacrificial oxide film and the second sacrificial oxide film such that the lower mirror is floated on the semiconductor substrate.