US20080297882A1 - Apparatus and method for controlling optics propagation based on a transparent metal stack - Google Patents

Apparatus and method for controlling optics propagation based on a transparent metal stack Download PDF

Info

Publication number
US20080297882A1
US20080297882A1 US10/627,989 US62798903A US2008297882A1 US 20080297882 A1 US20080297882 A1 US 20080297882A1 US 62798903 A US62798903 A US 62798903A US 2008297882 A1 US2008297882 A1 US 2008297882A1
Authority
US
United States
Prior art keywords
air gap
regions
region
stack
light propagation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/627,989
Inventor
Michael Scalora
Mark Bloemer
Salvatore Baglio
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US10/627,989 priority Critical patent/US20080297882A1/en
Publication of US20080297882A1 publication Critical patent/US20080297882A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/02Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the intensity of light

Definitions

  • the present invention relates to transparent metal stacks.
  • Micro-electro-mechanical-switches have been used in such applications as pressure sensors, accelerometers, and nozzles, and have been proposed for use in radio frequency (RF) telecommunications systems.
  • RF radio frequency
  • MEMS switches have been developed.
  • Petersen, K. “Micromechanical Membrane Switches on Silicon,” IBM J. Res. Develop., vol. 23, 1979, pp. 376-385 describes a chemical etching process for fabricating a mechanical switch, which is sensitive to vibrations and has poor insertion loss and isolation.
  • Gretillat et al “Electrostatic Polysilicon Microrelays Integrated with MOSFETs,” in proceedings of Micro Electro Mechanical Systems Workshop, 1994, pp.
  • 97-101 describes a switch for use in an automated testing applications.
  • the switch exhibits large insertion loss and high frequency capacitive coupling to its polysilicon cantilever arm in its off-state.
  • Yao et al. “A Surface Micromachined Minature Switch for Telecommunications Applications with Signal Frequencies from DC up to 4 GHz” In Tech. Digest, Transducer-95, Swiss, Sweden, Jun. 25-29, 1995, pp. 384-387 describes a switch for use in RF telecommunications that uses electrostatic actuation to control a silicon dioxide cantilever arm to open and close a signal line, and has an electrical isolation of ⁇ 50 dB and an insertion loss of 0.1 dB at 4 GHz.
  • optical devices that perform various tasks in the control of these optical signals.
  • Such devices include tunable filters and optical limiters.
  • PBG photonic band gap
  • Uniform PBG structures typically comprise a stack of alternating layers of refractive materials of similar thicknesses, such as gallium arsenide and aluminum arsenide, which exhibit photonic band gaps in their transmission spectra. These alternating layers have different indices of refraction and can be deposited by well known deposition techniques onto a substrate.
  • a photonic signal of a given frequency ( ⁇ ) By sending a photonic signal of a given frequency ( ⁇ ) through a uniform PGB device, the discontinuity of the indices of refraction imparts a delay to the photonic signal. These devices slow down the photonic signal as a result of scattering inside the uniform PBG structure. Since the photonic delay is proportional to the square of the number of periods contained in the uniform PBG structure, a device can be constructed that imparts a predetermined delay to a photonic signal.
  • the physical processes involved in the photonic signal delay imparted by a uniform PBG structure are described in detail in Scalora, et al., “Ultrashort pulse propagation at the photonic band edge: large tunable group delay with minimal distortion and loss,” Phys. Rev. E Rapid Comm. 54(2), R1078-R1081 (August 1996), which is incorporated by reference herein in its entirety.
  • an external electric field is applied in order to shift the location of the transmission resonance inside a photonic band gap device to induce changes in the velocity of an externally injected pulse of light.
  • a method by which the index of refraction of the affected material layer can be changed. Changing the refractive index of the layer causes the desired change in the velocity of the incident light beam.
  • the index of refraction of most ordinary materials can be changed only slightly with the utilization of externally applied electric fields.
  • the index of refraction of GaAs can be changed by approximately one part in 1000 if an ordinary electric field is applied across the 100-nm layer discussed above. That is, a shift in the index of refraction occurs from 3.4 to 3.401. While this shift can be considered meaningful, experimentally observable, and useful for some applications like an optical delay line, this shift is too small and impractical for many other applications of interest.
  • this change in index of refraction from 3.4 to 3.401 can shift the transmission resonance in a photonic band gap structure by approximately 0.5 nm.
  • an optical limiter must stop a coherent signal regardless of its wavelength. This means it must distinguish between low intensity light levels, such as those of ambient light, and a high intensity coherent light, such as a laser beam.
  • the device must be able to discriminate between different colors of the incident light, coherent or not, over the entire visible range. That is, it must have a dynamic range approximately 1000 times greater than the shift discussed in our previous patent application and incorporated by reference herein in its entirety, i.e., from 0.5 nm to approximately 500 nm or more.
  • the present invention generally relates to a device and method of optics propagation and signal control integrated with micro-electro-mechanical-switches (MEMS).
  • MEMS micro-electro-mechanical-switches
  • the present invention relates to modifying optical transmission properties of a transparent, multilayer metal stack by mechanically varying the thickness of an air gap between layers in the stack. This is accomplished with the novel approach of utilizing MEMS coupled with the stack to change the index of refraction in a given layer of the transparent multilayer metal stack.
  • this is accomplished by developing a hybrid combination of transparent multilayer stacks and MEMS, wherein an air gap is used as one of the dielectric layers.
  • the air gap thickness can be controlled by the MEMS device thereby enabling much greater control of the index of refraction.
  • FIG. 1A is a representation of a transparent metal stack.
  • FIG. 1B is a chart of the transmission function of the transparent metal stack of FIG. 1A .
  • FIG. 2A is a representation of a transparent metal stack of the present invention including the novel air gap as one layer and in the open position.
  • FIG. 2B is a representation of a transparent metal stack of the present invention including the novel air gap as one layer and in the closed position.
  • FIG. 3 is a chart of the transmission function (depicted as a solid curved line) of the device arrangement of FIG. 2A , and a chart of the transmission function (depicted as a dashed line) of the device arrangement of FIG. 2B .
  • FIG. 4 is a series of transmission functions for an embodiment of an air gap device according to the present invention, each of the transmission functions corresponding to a predetermined air gap width in the air gap device.
  • FIG. 5 is a diagram of an actual micro-electro-mechanical optical switch constructed in accordance with the present invention.
  • FIG. 1A An example of a transparent metal stack 5 is shown in FIG. 1A , and the transmission function 20 thereof is shown in FIG. 1B .
  • Stack 5 consists of alternating layers of silver and any material whose initial refractive index is approximately 1.37, with thickness 140 nm.
  • the corresponding transmission function 20 is represented as a solid-line of FIG. 1B : the structure is transparent to wavelengths that fall in the visible range.
  • the transmission function changes.
  • the changed transmission function is depicted by the dashed line in FIG. 1B .
  • the device is now opaque to ALL radiation, from ultraviolet to microwave fields. This kind of operation can best be described as optical limiting. That is, the device can react to a perceived threat, which might be in the form of a laser or microwave field, by completely shutting itself down and not allowing the propagation of any radiation. Unfortunately it is difficult to find materials that respond in the manner described above, by changing their index of refraction by a factor of 2 via the application of a magnetic field, for example.
  • metal stack 5 comprising alternating layers of a metal 10 , such as silver, and any dielectric material 15 whose initial refractive index is approximately 1.37, with thickness 140 nm. It is understood that the measurements herein are used for illustration and other thickness' can be used if in the appropriate proportion.
  • the transmission function waveform 20 is shown in FIG. 1B , wherein it is shown that the structure is transparent to wavelengths that fall in the visible range.
  • the Y-Axis 25 depicts the transmission level and the X-axis 30 depicts the wavelength in nanometers.
  • Micro-electro-mechanical-switches can be a potential alternative to nonlinear optical devices.
  • nonlinear optics as described in the patent applications incorporated above by reference, a high intensity beam in the form of an electric field, a magnetic field, or both, is used in order to change the physical properties of an ordinary dielectric material.
  • physical properties we generally mean the index of refraction of the material, which could be a type of glass for example, or a semiconductor like Gallium Arsenide (GaAs).
  • the device limits the transmission of high intensity light and will have a dynamic range on the order of 100 nm or more.
  • a transparent metal stack 200 includes a left stack region 200 a and a right stack region 200 b separated by a dielectric air gap layer 205 .
  • Air has a refractive index equal to 1.
  • the important parameter here is the optical path of the air gap, which can be made to be equivalent to the optical path of the other dielectric layers by controlling its thickness 210 .
  • a micro-electro-mechanical-switch assembly 212 controls the thickness 210 of air gap layer 205 by displacing left and right stack regions 200 a and 200 b toward or away from each other.
  • MEMS assembly 212 includes an actuator unit 214 coupled with a left arm 216 a and a right arm 216 b .
  • Left and right arms 216 a and 216 b are in respective contact with left and right stack regions 200 a and 200 b .
  • Actuator unit 214 displaces arms 216 a and 216 b , and as a result, left and right stack regions 200 a and 200 b , toward and away from each other, in response to a control signal 218 applied to actuator unit 214 , to thereby control thickness 210 of air gap layer 205 .
  • FIG. 2A represents a device arrangement wherein MEMS assembly 212 has established an air gap thickness 210 .
  • FIG. 2B represents a device arrangement wherein MEMS assembly 212 has established an air gap thickness of approximately zero by bringing left and right stack regions 200 a and 200 b together from their separated positions in FIG. 2A .
  • the respective transmission functions of the example device corresponding to the arrangements of FIGS. 2A and 2B are schematically represented in FIG. 3 by a solid line curve (for FIG. 2A ) and a dashed line curve (for FIG. 2B ), wherein the transmission percentage light propagation 315 is represented by the Y-axis and the wavelength is represented by the X-axis 320 .
  • the device When the width of the air gap 210 depicted in FIG. 2A is approximately 150 nm, the device allows nearly 30% of the incident light to be transmitted in the visible range as shown at transmission peak 300 of FIG. 3 . All other radiation over the entire spectrum is reflected or slightly absorbed as represented by a transmission low level 305 of FIG. 3 .
  • the air gap width is reduced to approximately zero, as shown at 220 in FIG. 2B , we have a continuous layer of MgF2 50 nm wide in the center 225 of the structure. From the optical point of view, this layer spoils the resonance tunneling phenomenon which otherwise allows the propagation of the visible wavelengths. This absence of propagation is illustrated as the dashed line 310 of FIG. 3 .
  • this central layer falls below a certain value, it ceases to be effective, and could in principle be removed.
  • the thin MgF2 layers serve as protective layers for the outer silver layer. Therefore, when the two sides are touching or nearly touching, as shown in FIG. 2B , the calculation shows that the transmission through the stack is reduced to approximately 0.3%, or approximately a factor of 100 less compared to the “open” state, as shown in FIG. 2A .
  • a 60% change in the optical path of the air gap layer allows a drastic change of the transmissive properties of the device, as shown in FIG. 3 .
  • the device depicted in FIGS. 2A and 2B can be an optical limiter, which allows light to be transmitted in the open position, and which rejects most of the light in the closed position.
  • An example dielectric material that was used is MgF2.
  • other dielectric materials such as Silicon Nitride, or Titanium Dioxide can be used.
  • the tunability is graphically depicted in FIG. 4 wherein the X-axis 460 is the air gap thickness in nm and the Y-axis 405 is the percentage light propagation.
  • the design is similar to the apparatus of FIGS. 2A and 2B , except that in this embodiment the air gap thickness varies from 470 to 550 nm.
  • transmission profiles 410 , 420 , 430 , 440 and 450 respectively correspond to exemplary air gap thicknesses 470 nm, 490 nm, 510 nm, 530 nm and 550 nm.
  • the graphical illustrations are by way of example only and it is understood that any variations of the air gap thickness can be used depending on the characteristics of the tunable filter desired. It is noted that it is possible to incorporate two or more air gaps in the device, which allows for greater tunability control.
  • Switch 500 includes an upper silicon section 502 a , and a substantially identical, opposing lower silicon section 502 b , bonded together to form a cavity 504 between the upper and lower sections.
  • Upper section 502 a includes a pair of substrates 504 a and 506 a spaced apart from one another in a lateral direction L, and a transparently thin, laterally extending, flexible membrane 508 a between the spaced substrates.
  • lower section 502 b includes a pair of spaced substrates 504 b and 506 b and a transparently thin, laterally extending, membrane 508 b between the spaced substrates.
  • Upper and lower silicon sections 502 a and 502 b are bonded together at seems 510 .
  • Upper and lower silicon sections 502 a and 502 b can be fabricated using a bulk micro-machining technique. Also, silicon sections 502 a and 502 b can be made of suitable materials other than silicon.
  • a pair of PBG multilayer stack regions 512 a and 512 b constructed in accordance with the present invention to exhibit desired optical properties, are deposited on respective inner surfaces of membranes 508 a and 508 b to thereby oppose one another within cavity 504 .
  • a first pair of laterally spaced actuators 514 a and a second pair of laterally spaced actuators 514 b opposing the first pair are respectively embedded in the outer surfaces of the upper and lower sections 502 a and 502 b .
  • Actuator pairs 514 a and 514 b are respectively positioned at edge portions of flexible membranes 508 a and 508 b and control a separation or width 520 between opposing stack regions 512 a and 512 b by displacing the respective deformable membranes in a vertical direction V.
  • Each actuator pair 514 a / 514 b advantageously maintains an even or level orientation of the respective membrane 508 a / 508 b , and thus stack region 512 a / 512 b , while displacing the membrane in direction V because of the laterally spaced configuration of each actuator pair. Accordingly, the optical transmission of a light beam 522 , directed at stack region 512 b as depicted in FIG. 5 , through optical switch 500 is controlled by varying separation 520 using actuator pairs 514 a and/or 514 b , as described above.

Abstract

A device and method of optics propagation and signal control integrated with micro-electro-mechanical-switches (MEMS). This device modifies optical transmission properties of a transparent multilayer metal stack by mechanically varying the thickness of an air gap between layers in the stack This is accomplished by utilizing MEMS coupled with the stack to change the optical path in a given layer of the transparent multilayer metal stack. This can be accomplished by developing a hybrid combination of transparent multilayer stacks and MEMS, wherein an air gap is used as one of the dielectric layers. The air gap thickness can be controlled by the MEMS device thereby enabling dramatic control of the optical path.

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • This application is a continuation of U.S. Non-Provisional Patent Application No. 09/471,035, filed Dec. 23, 1999, entitled “Apparatus and Method for Controlling Optics Propagation Based On a Transparent Metal Stack,” which is incorporated herein by reference in its entirety.
  • This patent application is related to the following applications:
  • 1. “Photonic Bandgap Apparatus and Method for Delaying Photonic Signals,” Ser. No. 08/584,403, by J. Dowling, M. Scalora, M. Bloemer, M. Tocci, C. Bowden, R. Fork, S. Reinhardt, and R. Flynn, filed on Jan. 11, 1996, now pending and incorporated in its entirety herein by reference;
  • 2. “Photonic Signal Frequency Conversion Using a Photonic Band Gap Structure,” Ser. No. 09/382,690, by Scalora et al., filed on Aug. 25, 1999, now pending, which is a continuation of International Application PCT/US98/06378, with an international filing date of Apr. 2, 1998, now pending and incorporated in its entirety herein by reference;
  • 3. “Photonic Band Gap Device and Method Using a Periodicity Defect Region to Increase Photonic Signal Delay,” Ser. No. 09/250,283, by M. Scalora et al., filed on Feb. 16, 1999, now pending and incorporated in its entirety herein by reference;
  • 4. “Photonic Band Gap Device and Method Using a Periodicity Defect Region Doped with a Gain Medium to Increase Photonic Signal Delay,” Ser. No. 60/134,536, by M. Scalora, filed on May 17, 1999, now pending and incorporated in its entirety herein by reference;
  • 5. “Efficient Non-linear Phase Shifting Using a Photonic Band Gap Structure,” Ser. No. 60/156,961, by G. D'Aguanno, filed on Sep. 30, 1999, now pending and incorporated in its entirety herein by reference; and
  • 6. “Photonic Signal Reflectivity and Transmissivity Control Using a Photonic Band Gap Structure” Ser. No. 09/471,036, G. D'Aguanno, M. Centini, C. Sibilia, M. Scalora and M. Bloemer, filed on Dec. 23, 1999, and incorporated in its entirety herein by reference.
  • STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
  • This invention was made with Government support under Contract DAAHO1-96-R234 awarded by the U.S. Army Missile Command. The Government has certain rights in the invention.
  • BACKGROUND OF THE INVENTION
  • 1. Field of the Invention
  • The present invention relates to transparent metal stacks.
  • 2. Background Art
  • Micro-electro-mechanical-switches (MEMS) have been used in such applications as pressure sensors, accelerometers, and nozzles, and have been proposed for use in radio frequency (RF) telecommunications systems. In particular, a number of different types of MEMS switches have been developed. Petersen, K. “Micromechanical Membrane Switches on Silicon,” IBM J. Res. Develop., vol. 23, 1979, pp. 376-385 describes a chemical etching process for fabricating a mechanical switch, which is sensitive to vibrations and has poor insertion loss and isolation. Gretillat et al, “Electrostatic Polysilicon Microrelays Integrated with MOSFETs,” in proceedings of Micro Electro Mechanical Systems Workshop, 1994, pp. 97-101 describes a switch for use in an automated testing applications. The switch exhibits large insertion loss and high frequency capacitive coupling to its polysilicon cantilever arm in its off-state. Yao et al. “A Surface Micromachined Minature Switch for Telecommunications Applications with Signal Frequencies from DC up to 4 GHz” In Tech. Digest, Transducer-95, Stockholm, Sweden, Jun. 25-29, 1995, pp. 384-387 describes a switch for use in RF telecommunications that uses electrostatic actuation to control a silicon dioxide cantilever arm to open and close a signal line, and has an electrical isolation of −50 dB and an insertion loss of 0.1 dB at 4 GHz. These three documents are incorporated in their entireties herein by reference.
  • The fields of communications and data processing are currently transitioning from using electrical signals to using optical signals. As a result, there is an increased need for optical devices that perform various tasks in the control of these optical signals. Such devices include tunable filters and optical limiters.
  • One method of creating a low distortion, controllable photonic delay is through the use of photonic band gap (PBG) structures. Uniform PBG structures typically comprise a stack of alternating layers of refractive materials of similar thicknesses, such as gallium arsenide and aluminum arsenide, which exhibit photonic band gaps in their transmission spectra. These alternating layers have different indices of refraction and can be deposited by well known deposition techniques onto a substrate.
  • By sending a photonic signal of a given frequency (ω) through a uniform PGB device, the discontinuity of the indices of refraction imparts a delay to the photonic signal. These devices slow down the photonic signal as a result of scattering inside the uniform PBG structure. Since the photonic delay is proportional to the square of the number of periods contained in the uniform PBG structure, a device can be constructed that imparts a predetermined delay to a photonic signal. The physical processes involved in the photonic signal delay imparted by a uniform PBG structure are described in detail in Scalora, et al., “Ultrashort pulse propagation at the photonic band edge: large tunable group delay with minimal distortion and loss,” Phys. Rev. E Rapid Comm. 54(2), R1078-R1081 (August 1996), which is incorporated by reference herein in its entirety.
  • With the above methodology, an external electric field is applied in order to shift the location of the transmission resonance inside a photonic band gap device to induce changes in the velocity of an externally injected pulse of light. By varying the strength of the applied field, a method by which the index of refraction of the affected material layer can be changed. Changing the refractive index of the layer causes the desired change in the velocity of the incident light beam.
  • However, the index of refraction of most ordinary materials can be changed only slightly with the utilization of externally applied electric fields. For example, the index of refraction of GaAs can be changed by approximately one part in 1000 if an ordinary electric field is applied across the 100-nm layer discussed above. That is, a shift in the index of refraction occurs from 3.4 to 3.401. While this shift can be considered meaningful, experimentally observable, and useful for some applications like an optical delay line, this shift is too small and impractical for many other applications of interest. As an example, this change in index of refraction from 3.4 to 3.401 can shift the transmission resonance in a photonic band gap structure by approximately 0.5 nm. While this shift may be adequate for control of the velocity of an optical pulse, it is completely inadequate for device applications such as optical limiters and tunable filters wherein device requirements can be very demanding. For example, an optical limiter must stop a coherent signal regardless of its wavelength. This means it must distinguish between low intensity light levels, such as those of ambient light, and a high intensity coherent light, such as a laser beam. In addition, the device must be able to discriminate between different colors of the incident light, coherent or not, over the entire visible range. That is, it must have a dynamic range approximately 1000 times greater than the shift discussed in our previous patent application and incorporated by reference herein in its entirety, i.e., from 0.5 nm to approximately 500 nm or more.
  • Hence, there is a need for a device and method to change the index of refraction by greater than a factor of 2 in a number of readily available materials.
  • BRIEF SUMMARY OF THE INVENTION
  • The present invention generally relates to a device and method of optics propagation and signal control integrated with micro-electro-mechanical-switches (MEMS). In particular, the present invention relates to modifying optical transmission properties of a transparent, multilayer metal stack by mechanically varying the thickness of an air gap between layers in the stack. This is accomplished with the novel approach of utilizing MEMS coupled with the stack to change the index of refraction in a given layer of the transparent multilayer metal stack.
  • According to one embodiment of the present invention, this is accomplished by developing a hybrid combination of transparent multilayer stacks and MEMS, wherein an air gap is used as one of the dielectric layers. The air gap thickness can be controlled by the MEMS device thereby enabling much greater control of the index of refraction.
  • Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.
  • BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
  • The present invention is described with reference to the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.
  • FIG. 1A is a representation of a transparent metal stack.
  • FIG. 1B is a chart of the transmission function of the transparent metal stack of FIG. 1A.
  • FIG. 2A is a representation of a transparent metal stack of the present invention including the novel air gap as one layer and in the open position.
  • FIG. 2B is a representation of a transparent metal stack of the present invention including the novel air gap as one layer and in the closed position.
  • FIG. 3 is a chart of the transmission function (depicted as a solid curved line) of the device arrangement of FIG. 2A, and a chart of the transmission function (depicted as a dashed line) of the device arrangement of FIG. 2B.
  • FIG. 4 is a series of transmission functions for an embodiment of an air gap device according to the present invention, each of the transmission functions corresponding to a predetermined air gap width in the air gap device.
  • FIG. 5 is a diagram of an actual micro-electro-mechanical optical switch constructed in accordance with the present invention.
  • DETAILED DESCRIPTION OF THE INVENTION
  • An example of a transparent metal stack 5 is shown in FIG. 1A, and the transmission function 20 thereof is shown in FIG. 1B. Stack 5 consists of alternating layers of silver and any material whose initial refractive index is approximately 1.37, with thickness 140 nm. The corresponding transmission function 20 is represented as a solid-line of FIG. 1B: the structure is transparent to wavelengths that fall in the visible range.
  • An optical path is a quantity that is defined in terms of the index of refraction and the physical thickness of any material. More precisely, the optical path D is the product of the index of refraction and the physical thickness (or absolute thickness) of the material, i.e., D=nL. For example, the index of refraction of GaAs is n=3.4 at a wavelength λ=1.5 microns. The optical path of a 100-nm thick GaAs layer (L=100 nm) is D=340 nm at a wavelength of 1.5 microns. Therefore changing the index of refraction in a given layer is equivalent to modifying the optical path of that layer.
  • Assuming that one can apply an external excitation to the dielectric layers such that the effective path of each layer now become approximately 50 nm, then the transmission function changes. The changed transmission function is depicted by the dashed line in FIG. 1B. The device is now opaque to ALL radiation, from ultraviolet to microwave fields. This kind of operation can best be described as optical limiting. That is, the device can react to a perceived threat, which might be in the form of a laser or microwave field, by completely shutting itself down and not allowing the propagation of any radiation. Unfortunately it is difficult to find materials that respond in the manner described above, by changing their index of refraction by a factor of 2 via the application of a magnetic field, for example.
  • Referring again to FIG. 1A, metal stack 5 comprising alternating layers of a metal 10, such as silver, and any dielectric material 15 whose initial refractive index is approximately 1.37, with thickness 140 nm. It is understood that the measurements herein are used for illustration and other thickness' can be used if in the appropriate proportion. The transmission function waveform 20 is shown in FIG. 1B, wherein it is shown that the structure is transparent to wavelengths that fall in the visible range. The Y-Axis 25 depicts the transmission level and the X-axis 30 depicts the wavelength in nanometers.
  • Micro-electro-mechanical-switches, or MEMS, can be a potential alternative to nonlinear optical devices. In nonlinear optics, as described in the patent applications incorporated above by reference, a high intensity beam in the form of an electric field, a magnetic field, or both, is used in order to change the physical properties of an ordinary dielectric material. By physical properties, we generally mean the index of refraction of the material, which could be a type of glass for example, or a semiconductor like Gallium Arsenide (GaAs).
  • In the present application we describe a device based on a hybrid combination of transparent metal multilayer stacks and MEMS that will perform approximately as outlined above. The device limits the transmission of high intensity light and will have a dynamic range on the order of 100 nm or more.
  • An example device is described below with reference to FIGS. 2A and 2B. With reference to FIG. 2A, a transparent metal stack 200 includes a left stack region 200 a and a right stack region 200 b separated by a dielectric air gap layer 205. Air has a refractive index equal to 1. The important parameter here is the optical path of the air gap, which can be made to be equivalent to the optical path of the other dielectric layers by controlling its thickness 210.
  • To this end, a micro-electro-mechanical-switch assembly 212 controls the thickness 210 of air gap layer 205 by displacing left and right stack regions 200 a and 200 b toward or away from each other. MEMS assembly 212 includes an actuator unit 214 coupled with a left arm 216 a and a right arm 216 b. Left and right arms 216 a and 216 b are in respective contact with left and right stack regions 200 a and 200 b. Actuator unit 214 displaces arms 216 a and 216 b, and as a result, left and right stack regions 200 a and 200 b, toward and away from each other, in response to a control signal 218 applied to actuator unit 214, to thereby control thickness 210 of air gap layer 205.
  • FIG. 2A represents a device arrangement wherein MEMS assembly 212 has established an air gap thickness 210. On the other hand, FIG. 2B represents a device arrangement wherein MEMS assembly 212 has established an air gap thickness of approximately zero by bringing left and right stack regions 200 a and 200 b together from their separated positions in FIG. 2A.
  • The results below are of a mathematical model that describes light propagation inside the multilayer stack. It is assumed the stack comprises the following arrangement of materials:
  • Glass Substrate
    • Ag 20.00 nm
    • MgF2 150.00
    • Ag 25.00
    • MgF2 149.80
    • Ag 60.00
    • MgF2 25.00
      Air Layer 205 of variable width 210:
    • MgF2 25.00 nm
    • Ag 60.00
    • MgF2 150.00
    • Ag 25.00
    • MgF2 150.00
    • Ag 20.00
    Glass Substrate
  • The respective transmission functions of the example device corresponding to the arrangements of FIGS. 2A and 2B are schematically represented in FIG. 3 by a solid line curve (for FIG. 2A) and a dashed line curve (for FIG. 2B), wherein the transmission percentage light propagation 315 is represented by the Y-axis and the wavelength is represented by the X-axis 320.
  • When the width of the air gap 210 depicted in FIG. 2A is approximately 150 nm, the device allows nearly 30% of the incident light to be transmitted in the visible range as shown at transmission peak 300 of FIG. 3. All other radiation over the entire spectrum is reflected or slightly absorbed as represented by a transmission low level 305 of FIG. 3. On the other hand, if the air gap width is reduced to approximately zero, as shown at 220 in FIG. 2B, we have a continuous layer of MgF2 50 nm wide in the center 225 of the structure. From the optical point of view, this layer spoils the resonance tunneling phenomenon which otherwise allows the propagation of the visible wavelengths. This absence of propagation is illustrated as the dashed line 310 of FIG. 3. If the thickness of this central layer falls below a certain value, it ceases to be effective, and could in principle be removed. However, when the stacks are separated, the thin MgF2 layers serve as protective layers for the outer silver layer. Therefore, when the two sides are touching or nearly touching, as shown in FIG. 2B, the calculation shows that the transmission through the stack is reduced to approximately 0.3%, or approximately a factor of 100 less compared to the “open” state, as shown in FIG. 2A.
  • Using this approach, therefore, it becomes possible to replace nonlinear optical interactions with ordinary oscillations or motions of mechanical systems. A 60% change in the optical path of the air gap layer (or any other layer within the structure as long as it is possible to change its optical path by a large amount) allows a drastic change of the transmissive properties of the device, as shown in FIG. 3. For example, and not by way of limitation, the device depicted in FIGS. 2A and 2B can be an optical limiter, which allows light to be transmitted in the open position, and which rejects most of the light in the closed position. An example dielectric material that was used is MgF2. However, other dielectric materials, such as Silicon Nitride, or Titanium Dioxide can be used.
  • Operation as a tunable filter is slightly different, with theoretical results illustrated in FIG. 4, wherein the percentage light propagation is the Y-axis 405 and the air gap thickness is the X-axis 460. For illustration, Silicon Nitride has been used in the following device layer configuration:
  • Glass substrate
    • SI3N4 65.00 (nm)
    • AG 10.00
    • SI3N4 98.00
    • AG 20.00
    • SI3N4 94.00
    • AG 30.00
      AIR layer having exemplary widths 470; 490; 510; 530; and 550 nm
    • AG 30.00
    • SI3N4 94.00
    • AG 20.00
    • SI3N4 98.00
    • AG 10.00
    • SI3N4 65.00
      Glass substrate
  • The tunability is graphically depicted in FIG. 4 wherein the X-axis 460 is the air gap thickness in nm and the Y-axis 405 is the percentage light propagation. The design is similar to the apparatus of FIGS. 2A and 2B, except that in this embodiment the air gap thickness varies from 470 to 550 nm. In FIG. 4, transmission profiles 410, 420, 430, 440 and 450 respectively correspond to exemplary air gap thicknesses 470 nm, 490 nm, 510 nm, 530 nm and 550 nm. The graphical illustrations are by way of example only and it is understood that any variations of the air gap thickness can be used depending on the characteristics of the tunable filter desired. It is noted that it is possible to incorporate two or more air gaps in the device, which allows for greater tunability control.
  • A micro-electro-mechanical optical switch 500 constructed in accordance with the principles of the present invention is depicted in FIG. 5. Switch 500 includes an upper silicon section 502 a, and a substantially identical, opposing lower silicon section 502 b, bonded together to form a cavity 504 between the upper and lower sections. Upper section 502 a includes a pair of substrates 504 a and 506 a spaced apart from one another in a lateral direction L, and a transparently thin, laterally extending, flexible membrane 508 a between the spaced substrates. Similarly, lower section 502 b includes a pair of spaced substrates 504 b and 506 b and a transparently thin, laterally extending, membrane 508 b between the spaced substrates. Upper and lower silicon sections 502 a and 502 b are bonded together at seems 510. Upper and lower silicon sections 502 a and 502 b can be fabricated using a bulk micro-machining technique. Also, silicon sections 502 a and 502 b can be made of suitable materials other than silicon.
  • A pair of PBG multilayer stack regions 512 a and 512 b, constructed in accordance with the present invention to exhibit desired optical properties, are deposited on respective inner surfaces of membranes 508 a and 508 b to thereby oppose one another within cavity 504. A first pair of laterally spaced actuators 514 a and a second pair of laterally spaced actuators 514 b opposing the first pair are respectively embedded in the outer surfaces of the upper and lower sections 502 a and 502 b. Actuator pairs 514 a and 514 b are respectively positioned at edge portions of flexible membranes 508 a and 508 b and control a separation or width 520 between opposing stack regions 512 a and 512 b by displacing the respective deformable membranes in a vertical direction V. Each actuator pair 514 a/514 b advantageously maintains an even or level orientation of the respective membrane 508 a/508 b, and thus stack region 512 a/512 b, while displacing the membrane in direction V because of the laterally spaced configuration of each actuator pair. Accordingly, the optical transmission of a light beam 522, directed at stack region 512 b as depicted in FIG. 5, through optical switch 500 is controlled by varying separation 520 using actuator pairs 514 a and/or 514 b, as described above.
  • While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. Thus, the breadth and scope of the present invention should not be limited by any of the above described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims (12)

1. An apparatus for controlling light propagation, comprising:
a transparent metal stack with at least two regions, said regions being positioned so as to have at least one air gap between said at least two regions; and
mechanical actuator assembly coupled with the transparent metal stack and being constructed and arranged to displace at least one of said two regions in relation to the other region to vary a width of the air gap between said regions, whereby light propagation through the transparent metal stack is controlled in accordance with the width of the air gap.
2. The apparatus for controlling light propagation of claim 1, wherein the mechanical actuator assembly includes a micro-electromechanical switch.
3. The apparatus for controlling light propagation of claim 1, wherein the width of said air gap causes a variance in the index of refraction to be a factor of 2 or greater.
4. The apparatus for controlling light propagation of claim 1, wherein said at least two regions is exactly two regions, a first region and a second region, and wherein said at least one air gap is one air gap between said first region and said second region.
5. The apparatus for controlling light propagation of claim 1, wherein said at least two regions is exactly three regions, a first region, a second region and a third region, and wherein said at least one air gap is two air gaps independent in size, one air gap between said first and said second region and one air gap between said second and said third region.
6. The apparatus of claim 2, further comprising first and second substrate sections bonded together to form a cavity between the substrate sections, each substrate section including a transparently thin flexible membrane opposing the flexible membrane of the other substrate section, wherein the metal stack includes first and second opposing stack regions respectively deposited on the first and second flexible membranes to define the air gap between the first and second stack regions within the cavity, wherein the mechanical actuator assembly controls the air gap width between the first and second stack regions by displacing at least one of the flexible membranes, and an associated one of the first and second regions, toward or away from the other flexible membrane.
7. The apparatus of claim 6, wherein the mechanical actuator assembly is coupled with the first flexible membrane and is arranged and constructed to maintain a predetermined orientation of the first flexible membrane and first stack region while displacing the first flexible membrane and first stack region to control the light propagation.
8. The apparatus of claim 7, wherein the mechanical actuator assembly includes a first pair of spaced actuators contacting an outer surface of the first flexible membrane, and a second pair of spaced actuators contacting an outer surface of the second flexible membrane and positioned to oppose the first pair of actuators.
9. A method of controlling light propagation, comprising the steps of:
placing a transparent metal stack with at least two regions in the path of the light propagation that is to be controlled, said at least two regions having at least one air gap therebetween; and
varying a width of said at least one air gap to establish a desired light propagation characteristics and thereby control the light propagation.
10. The method of claim 9, wherein the step of varying the width of said at least one air gap is accomplished using a Micro-electro-mechanical switch
11. The method of claim 10, wherein the varying step includes the step of maintaining a predetermined orientation of the at least two regions while varying the width of the at least one air gap.
12. The method for controlling light propagation of claim 9, wherein said varying step varies the index of refraction by a factor of 2 or more.
US10/627,989 1999-12-23 2003-07-28 Apparatus and method for controlling optics propagation based on a transparent metal stack Abandoned US20080297882A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US10/627,989 US20080297882A1 (en) 1999-12-23 2003-07-28 Apparatus and method for controlling optics propagation based on a transparent metal stack

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US09/471,035 US6339493B1 (en) 1999-12-23 1999-12-23 Apparatus and method for controlling optics propagation based on a transparent metal stack
US09/987,745 US20020163708A1 (en) 1999-12-23 2001-11-15 Apparatus and method for controlling optics propagation based on a transparent metal stack
US10/627,989 US20080297882A1 (en) 1999-12-23 2003-07-28 Apparatus and method for controlling optics propagation based on a transparent metal stack

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US09/987,745 Continuation US20020163708A1 (en) 1999-12-23 2001-11-15 Apparatus and method for controlling optics propagation based on a transparent metal stack

Publications (1)

Publication Number Publication Date
US20080297882A1 true US20080297882A1 (en) 2008-12-04

Family

ID=23870016

Family Applications (3)

Application Number Title Priority Date Filing Date
US09/471,035 Expired - Fee Related US6339493B1 (en) 1999-12-23 1999-12-23 Apparatus and method for controlling optics propagation based on a transparent metal stack
US09/987,745 Abandoned US20020163708A1 (en) 1999-12-23 2001-11-15 Apparatus and method for controlling optics propagation based on a transparent metal stack
US10/627,989 Abandoned US20080297882A1 (en) 1999-12-23 2003-07-28 Apparatus and method for controlling optics propagation based on a transparent metal stack

Family Applications Before (2)

Application Number Title Priority Date Filing Date
US09/471,035 Expired - Fee Related US6339493B1 (en) 1999-12-23 1999-12-23 Apparatus and method for controlling optics propagation based on a transparent metal stack
US09/987,745 Abandoned US20020163708A1 (en) 1999-12-23 2001-11-15 Apparatus and method for controlling optics propagation based on a transparent metal stack

Country Status (4)

Country Link
US (3) US6339493B1 (en)
EP (1) EP1244929A2 (en)
AU (1) AU2587201A (en)
WO (1) WO2001046740A2 (en)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6339493B1 (en) * 1999-12-23 2002-01-15 Michael Scalora Apparatus and method for controlling optics propagation based on a transparent metal stack
US6556338B2 (en) * 2000-11-03 2003-04-29 Intpax, Inc. MEMS based variable optical attenuator (MBVOA)
KR100425776B1 (en) * 2002-04-23 2004-04-01 전자부품연구원 Micro actuator
US20040212026A1 (en) * 2002-05-07 2004-10-28 Hewlett-Packard Company MEMS device having time-varying control
US6853476B2 (en) * 2003-04-30 2005-02-08 Hewlett-Packard Development Company, L.P. Charge control circuit for a micro-electromechanical device
US6829132B2 (en) * 2003-04-30 2004-12-07 Hewlett-Packard Development Company, L.P. Charge control of micro-electromechanical device
US7356969B1 (en) 2003-05-06 2008-04-15 Electronically Shaded Glass, Inc. Electronically shaded thin film transparent monochromatic liquid crystal display laminated window shading system
US20080143896A1 (en) * 2003-05-06 2008-06-19 Electronically Shaded Glass, Inc. Window shading system
WO2008108784A2 (en) * 2006-05-23 2008-09-12 Regents Of The Uninersity Of Minnesota Tunable finesse infrared cavity thermal detectors
EP2092285A4 (en) * 2006-12-08 2013-11-06 Univ Minnesota Detection beyond the standard radiation noise limit using reduced emissivity and optical cavity coupling
US8629398B2 (en) 2008-05-30 2014-01-14 The Regents Of The University Of Minnesota Detection beyond the standard radiation noise limit using spectrally selective absorption
DE102008059158B4 (en) 2008-11-27 2011-01-27 Carl Zeiss Ag Multilayer optical filter
FR2985724B1 (en) * 2012-01-16 2014-03-07 Saint Gobain SUBSTRATE PROVIDED WITH A STACK WITH THERMAL PROPERTIES COMPRISING FOUR METAL FUNCTIONAL LAYERS.

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6339493B1 (en) * 1999-12-23 2002-01-15 Michael Scalora Apparatus and method for controlling optics propagation based on a transparent metal stack

Family Cites Families (96)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3410625A (en) 1963-08-05 1968-11-12 Monsanto Co Multi-layer interference film with outermost layer for suppression of pass-band reflectance
US3698946A (en) 1969-11-21 1972-10-17 Hughes Aircraft Co Transparent conductive coating and process therefor
CH502603A (en) 1969-12-17 1971-01-31 Balzers Patent Beteilig Ag Multi-layer interference light filter with a broadband spectral transmission range
US3637294A (en) 1969-12-19 1972-01-25 Bell Telephone Labor Inc Interference filter with alternately designed pairs of dielectric layers
GB1292717A (en) 1970-02-04 1972-10-11 Rank Organisation Ltd Improvements relating to anti-reflection coatings
US3682528A (en) 1970-09-10 1972-08-08 Optical Coating Laboratory Inc Infra-red interference filter
CH523509A (en) 1970-09-18 1972-05-31 Balzers Patent Beteilig Ag Interference filter, consisting of a plurality of alternating high and low refractive index light-permeable layers on a light-permeable carrier, which reflects a certain wavelength band within a certain wavelength range, but allows the radiation of the other parts of the mentioned range to pass through
BE787599A (en) 1971-08-16 1973-02-16 Battelle Memorial Institute ANTISOLAR FILTERING AND THERMAL INSULATION GLASS
DE2203943C2 (en) 1972-01-28 1974-02-21 Flachglas Ag Delog-Detag, 8510 Fuerth Heat reflecting disk exhibiting good uniformity of color, process for its manufacture and its use
CH556548A (en) 1972-09-19 1974-11-29 Balzers Patent Beteilig Ag LOW-LOSS, HIGHLY REFLECTIVE MULTI-LAYER SYSTEM BUILT UP FROM ALTERNATING HIGH-REFLECTIVE AND LOW-REFLECTIVE OXIDE LAYERS.
DE2256441C3 (en) 1972-11-17 1978-06-22 Flachglas Ag Delog-Detag, 8510 Fuerth Color-neutral, heat-reflecting pane and its use in laminated safety panes and double panes when viewed through and from above
CH564785A5 (en) 1972-12-08 1975-07-31 Balzers Patent Beteilig Ag
DE2334152B2 (en) 1973-07-05 1975-05-15 Flachglas Ag Delog-Detag, 8510 Fuerth Heat-reflecting, 20 to 60% of the visible light transmitting window pane with improved color neutrality in the view and its use
GB1406940A (en) 1973-09-10 1975-09-17 Optical Coating Laboratory Inc Thermal control filter
US4556277A (en) 1976-05-27 1985-12-03 Massachusetts Institute Of Technology Transparent heat-mirror
US4189205A (en) 1978-02-21 1980-02-19 Infrared Industries, Inc. Coated copper reflector
US4179181A (en) 1978-04-03 1979-12-18 American Optical Corporation Infrared reflecting articles
US4229066A (en) 1978-09-20 1980-10-21 Optical Coating Laboratory, Inc. Visible transmitting and infrared reflecting filter
EP0012439A1 (en) 1978-12-13 1980-06-25 Mta Központi Fizikai Kutato Intezete Light modulator or light switch with variable transmission and method of making the same
US4269481A (en) 1979-07-06 1981-05-26 Rockwell International Corporation Multiple-cavity electro-optic tunable filter
US4240696A (en) 1979-11-13 1980-12-23 Rockwell International Corporation Multilayer electro-optically tunable filter
DE3109653A1 (en) 1980-03-31 1982-01-28 Jenoptik Jena Gmbh, Ddr 6900 Jena "RESONANCE ABSORBER"
JPS57195207A (en) 1981-05-26 1982-11-30 Olympus Optical Co Ltd Light absorbing film
US4590118A (en) 1983-02-17 1986-05-20 Teijin Limited Selective light transmission sheet
JPS59151108A (en) 1983-02-17 1984-08-29 Teijin Ltd Sheet having optically selective transmittability
US4525687A (en) 1983-02-28 1985-06-25 At&T Bell Laboratories High speed light modulator using multiple quantum well structures
USH182H (en) 1984-12-20 1987-01-06 Adjustable indicating device for load position
EP0215372A3 (en) 1985-09-17 1989-01-04 Siemens Aktiengesellschaft Edge interference filters for a wavelength division multiplexing optical communication system
EP0215371A3 (en) 1985-09-17 1989-01-04 Siemens Aktiengesellschaft Edge interference filters for a wavelength division multiplexing optical communication system
US4846551A (en) 1986-04-21 1989-07-11 Optical Coating Laboratory, Inc. Optical filter assembly for enhancement of image contrast and glare reduction of cathode ray display tube
US5071206A (en) 1986-06-30 1991-12-10 Southwall Technologies Inc. Color-corrected heat-reflecting composite films and glazing products containing the same
US5433988A (en) 1986-10-01 1995-07-18 Canon Kabushiki Kaisha Multi-layer reflection mirror for soft X-ray to vacuum ultraviolet ray
US4773717A (en) 1986-11-03 1988-09-27 Ovonic Synthetic Materials Co. Transparency having a second surface multilayer decorative coating
US4756602A (en) 1987-06-05 1988-07-12 Rockwell International Corporation Narrowband optical filter with partitioned cavity
JPS6480908A (en) 1987-09-22 1989-03-27 Nec Corp Spectral element
US5239406A (en) 1988-02-12 1993-08-24 Donnelly Corporation Near-infrared reflecting, ultraviolet protected, safety protected, electrochromic vehicular glazing
US5355245A (en) 1988-02-12 1994-10-11 Donnelly Corporation Ultraviolet protected electrochemichromic rearview mirror
US4838648A (en) 1988-05-03 1989-06-13 Optical Coating Laboratory, Inc. Thin film structure having magnetic and color shifting properties
US4915494A (en) 1988-07-06 1990-04-10 Harris Corporation Carbon-carbon mirror for space applications
JPH02170101A (en) 1988-12-23 1990-06-29 Minolta Camera Co Ltd Interference filter
JP2697882B2 (en) 1989-01-17 1998-01-14 古河電気工業株式会社 Optical filter
US5315437A (en) 1989-03-13 1994-05-24 Alfano Robert R Protective device for selectively reflecting high-intensity light over a broad spectral bandwidth
US5262894A (en) 1989-06-20 1993-11-16 The Dow Chemical Company Multicomponent, multilayer polymeric reflective bodies
US5506037A (en) 1989-12-09 1996-04-09 Saint Gobain Vitrage International Heat-reflecting and/or electrically heatable laminated glass pane
US5170290A (en) 1990-05-10 1992-12-08 The United States Of America As Represented By The Secretary Of The Air Force Comb optical interference filter
US5225930A (en) 1990-05-10 1993-07-06 The United States Of America As Represented By The Secretary Of The Air Force Comb optical interference filter
JPH05502310A (en) 1990-08-30 1993-04-22 バイラテック・シン・フィルムズ・インコーポレイテッド DC reactive sputtered optical coatings containing niobium oxide
JP2721436B2 (en) 1990-11-07 1998-03-04 沖電気工業株式会社 Second harmonic generator
US5111329A (en) 1990-11-28 1992-05-05 Ford Motor Company Solar load reduction panel with controllable light transparency
US5119232A (en) 1990-12-17 1992-06-02 Hughes Aircraft Company Infrared-transmissive optical window
US5337183A (en) 1991-02-01 1994-08-09 Yeda Research And Development Co. Ltd. Distributed resonant cavity light beam modulator
US5187461A (en) 1991-02-15 1993-02-16 Karl Brommer Low-loss dielectric resonator having a lattice structure with a resonant defect
US5233464A (en) 1991-03-20 1993-08-03 Costich Verne R Multilayer infrared filter
US5148504A (en) 1991-10-16 1992-09-15 At&T Bell Laboratories Optical integrated circuit designed to operate by use of photons
FI91564C (en) 1991-10-31 1994-07-11 Valtion Teknillinen Sensor
US5179468A (en) 1991-11-05 1993-01-12 Gte Products Corporation Interleaving of similar thin-film stacks for producing optical interference coatings
US5909280A (en) 1992-01-22 1999-06-01 Maxam, Inc. Method of monolithically fabricating a microspectrometer with integrated detector
US5302449A (en) 1992-03-27 1994-04-12 Cardinal Ig Company High transmittance, low emissivity coatings for substrates
US5315430A (en) 1992-04-15 1994-05-24 The United States Of America As Represented By The United States Department Of Energy Strained layer Fabry-Perot device
US5212584A (en) 1992-04-29 1993-05-18 At&T Bell Laboratories Tunable etalon filter
US5480722A (en) 1992-07-03 1996-01-02 Asahi Glass Company Ltd. Ultraviolet ray absorbent glass and method for preparing the same
US5345328A (en) 1992-08-12 1994-09-06 Sandia Corporation Tandem resonator reflectance modulator
AU5322594A (en) 1992-10-29 1994-05-24 Dow Chemical Company, The Formable reflective multilayer body
US5406573A (en) 1992-12-22 1995-04-11 Iowa State University Research Foundation Periodic dielectric structure for production of photonic band gap and method for fabricating the same
US5268785A (en) 1993-02-08 1993-12-07 The United States Of America As Represented By The Secretary Of The Army All-optical switch utilizing inversion of two-level systems
CH695281A5 (en) 1993-04-02 2006-02-28 Balzers Hochvakuum A method for manufacturing a filter, optical layer produced thereby, an optical component having such a layer and Braeunungsanlage with such an element.
CA2120875C (en) 1993-04-28 1999-07-06 The Boc Group, Inc. Durable low-emissivity solar control thin film coating
US5457570A (en) 1993-05-25 1995-10-10 Litton Systems, Inc. Ultraviolet resistive antireflective coating of Ta2 O5 doped with Al2 O3 and method of fabrication
US5513039A (en) 1993-05-26 1996-04-30 Litton Systems, Inc. Ultraviolet resistive coated mirror and method of fabrication
JPH06347734A (en) 1993-06-11 1994-12-22 Nec Corp Surface type optical switch
FR2710333B1 (en) 1993-09-23 1995-11-10 Saint Gobain Vitrage Int Transparent substrate provided with a stack of thin layers acting on solar and / or infrared radiation.
DE4334578C2 (en) 1993-10-11 1999-10-07 Dirk Winfried Rossberg Spectrally tunable infrared sensor
DE4407502A1 (en) 1994-03-07 1995-09-14 Leybold Ag Multi-layer coating
US5440421A (en) 1994-05-10 1995-08-08 Massachusetts Institute Of Technology Three-dimensional periodic dielectric structures having photonic bandgaps
WO1996011516A1 (en) 1994-10-05 1996-04-18 Massachusetts Institute Of Technology Resonant microcavities employing one-dimensional periodic dielectric waveguides
US5514476A (en) 1994-12-15 1996-05-07 Guardian Industries Corp. Low-E glass coating system and insulating glass units made therefrom
US5550373A (en) 1994-12-30 1996-08-27 Honeywell Inc. Fabry-Perot micro filter-detector
US5557462A (en) 1995-01-17 1996-09-17 Guardian Industries Corp. Dual silver layer Low-E glass coating system and insulating glass units made therefrom
US5506919A (en) * 1995-03-27 1996-04-09 Eastman Kodak Company Conductive membrane optical modulator
US5552882A (en) 1995-03-28 1996-09-03 Lyons; Donald R. Methods of and apparatus for calibrating precisely spaced multiple transverse holographic gratings in optical fibers
US5559825A (en) 1995-04-25 1996-09-24 The United States Of America As Represented By The Secretary Of The Army Photonic band edge optical diode
US5825490A (en) 1995-06-07 1998-10-20 Northrop Grumman Corporation Interferometer comprising translation assemblies for moving a first optical member relative to a second optical member
US5920391A (en) 1995-10-27 1999-07-06 Schlumberger Industries, S.A. Tunable Fabry-Perot filter for determining gas concentration
US5740287A (en) 1995-12-07 1998-04-14 The United States Of America As Represented By The Secretary Of The Army Optical switch that utilizes one-dimensional, nonlinear, multilayer dielectric stacks
US5615289A (en) 1995-12-07 1997-03-25 Jds Fitel Inc. Bandpass optical filter
EP0782017B1 (en) 1995-12-28 2009-08-05 Panasonic Corporation Optical waveguide, optical wavelength conversion device, and methods for fabricating the same
US5751466A (en) 1996-01-11 1998-05-12 University Of Alabama At Huntsville Photonic bandgap apparatus and method for delaying photonic signals
US5802232A (en) 1996-02-16 1998-09-01 Bell Communications Research, Inc. Bonded structure with portions of differing crystallographic orientations, particularly useful as a non linear optical waveguide
JP3209914B2 (en) 1996-03-19 2001-09-17 オークマ株式会社 Optical encoder
KR100252308B1 (en) 1997-01-10 2000-04-15 구본준, 론 위라하디락사 Thin film transistor array
US6031653A (en) 1997-08-28 2000-02-29 California Institute Of Technology Low-cost thin-metal-film interference filters
US5907427A (en) 1997-10-24 1999-05-25 Time Domain Corporation Photonic band gap device and method using a periodicity defect region to increase photonic signal delay
US6028693A (en) 1998-01-14 2000-02-22 University Of Alabama In Huntsville Microresonator and associated method for producing and controlling photonic signals with a photonic bandgap delay apparatus
US5914804A (en) 1998-01-28 1999-06-22 Lucent Technologies Inc Double-cavity micromechanical optical modulator with plural multilayer mirrors
US5949571A (en) * 1998-07-30 1999-09-07 Lucent Technologies Mars optical modulators
US5943155A (en) * 1998-08-12 1999-08-24 Lucent Techonolgies Inc. Mars optical modulators

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6339493B1 (en) * 1999-12-23 2002-01-15 Michael Scalora Apparatus and method for controlling optics propagation based on a transparent metal stack

Also Published As

Publication number Publication date
AU2587201A (en) 2001-07-03
EP1244929A2 (en) 2002-10-02
US6339493B1 (en) 2002-01-15
WO2001046740A3 (en) 2001-12-13
US20020163708A1 (en) 2002-11-07
WO2001046740A2 (en) 2001-06-28

Similar Documents

Publication Publication Date Title
US6519073B1 (en) Micromechanical modulator and methods for fabricating the same
US6339493B1 (en) Apparatus and method for controlling optics propagation based on a transparent metal stack
US5367585A (en) Integrated microelectromechanical polymeric photonic switch
US6594059B2 (en) Tilt mirror fabry-perot filter system, fabrication process therefor, and method of operation thereof
US7155083B2 (en) Monolithic waveguide/MEMS switch
US6970619B2 (en) Mechanically tunable optical devices such as interferometers
EP1560048B1 (en) Optical isolator utilizing a micro-resonator
Takahashi et al. A wavelength-selective add-drop switch using silicon microring resonator with a submicron-comb electrostatic actuator
Nielson et al. Integrated wavelength-selective optical MEMS switching using ring resonator filters
US6433911B1 (en) Frustrated total internal reflection-based micro-opto-electro-mechanical modulator/demodulator
US8155492B2 (en) Photonic crystal and method of fabrication
US6763154B2 (en) Methods and structures for the control of optical waveguide devices by stress
Wang et al. NEMS-based infrared metamaterial via tuning nanocantilevers within complementary split ring resonators
Beiranvand et al. Resonant-wavelength tuning of a fibonacci one dimensional photonic crystal filter at telecommunication wavelengths
Kosugi et al. Surface-normal electro-optic-polymer modulator with silicon subwavelength grating
US10578858B2 (en) Optomechanical non-reciprocal device
Veldhuis et al. Electrostatically actuated mechanooptical waveguide ON-OFF switch showing high extinction at a low actuation-voltage
Midolo et al. Nano‐Opto‐Electro‐Mechanical Systems for Integrated Quantum Photonics
Han et al. Terahertz devices with reconfigurable metamaterials by surface micromachining technique
Trimm et al. Dynamic MEMS-based photonic bandgap filter
Lee et al. Nano-electro-mechanical photonic crystal switch
Magel et al. Integrated optic switches for phased-array applications based on electrostatic actuation of metallic membranes
EP1536274A1 (en) Reconfigurable photonic bandgap device and method of configuring the same
Akdemir Wavelength Conversion Using Reconfigurable Photonic Crystal MEMS/NEMS Structures
Li et al. INSTRUCTIONS MICROMACHINED TUNABLE FILTER VIA ACTUATION OF FABRY-PAROT CAVITY

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION