+

WO2001086848A1 - Multiplexeur et demultiplexeur en longueur d'onde optique - Google Patents

Multiplexeur et demultiplexeur en longueur d'onde optique Download PDF

Info

Publication number
WO2001086848A1
WO2001086848A1 PCT/US2001/015129 US0115129W WO0186848A1 WO 2001086848 A1 WO2001086848 A1 WO 2001086848A1 US 0115129 W US0115129 W US 0115129W WO 0186848 A1 WO0186848 A1 WO 0186848A1
Authority
WO
WIPO (PCT)
Prior art keywords
optical
multiplexing device
constituent signals
optical element
optical multiplexing
Prior art date
Application number
PCT/US2001/015129
Other languages
English (en)
Inventor
Dennis R. Hollar
Original Assignee
Scivac, Inc.
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 Scivac, Inc. filed Critical Scivac, Inc.
Publication of WO2001086848A1 publication Critical patent/WO2001086848A1/fr

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
    • G02B6/29307—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide components assembled in or forming a solid transparent unitary block, e.g. for facilitating component alignment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
    • G01J3/02—Details
    • G01J3/0256—Compact construction
    • G01J3/0259—Monolithic
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
    • G02B6/2931—Diffractive element operating in reflection
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29316—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide
    • G02B6/29325—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide of the slab or planar or plate like form, i.e. confinement in a single transverse dimension only
    • G02B6/29328—Diffractive elements operating in reflection
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29316—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide
    • G02B6/29325—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide of the slab or planar or plate like form, i.e. confinement in a single transverse dimension only
    • G02B6/29329—Diffractive elements operating in transmission
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29379—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
    • G02B6/2938—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/34—Optical coupling means utilising prism or grating

Definitions

  • the invention relates to the field of fiber optic communication. More particularly, the invention relates to the field of optical wavelength division multiplexers and de-multiplexers for use in fiber optic communication systems.
  • an electro-optical switch can be used to modulate a laser beam, thus, converting a binary electrical signal into an optical signal, as for example, that produced by pulse code modulation (PCM).
  • PCM pulse code modulation
  • optical fibers have favorable signal transfer characteristics, such as relatively low attenuation, they may be utilized for communicating information over vast distances.
  • multiple optical signals may be combined into a wavelength division multiplexed (WDM) signal prior to communication via the optical fiber.
  • An optical wavelength multiplexer located at a first end of the fiber combines multiple optical channels (i.e. wavelengths corresponding to different lasers) into the WDM signal.
  • An optical wavelength demultiplexer located at a second end of the optical fiber separates the WDM signal back into its constituent channels or wavelengths.
  • a technique for de-multiplexing an optical WDM signal involves delivery of the combined wavelength signal to each of several band-pass filters.
  • the filters eliminate all but an in-band range of wavelengths for each channel which is then provided to an optical detector.
  • U.S. Patent No. 5,786,915 to Scobey discloses that multicolor light is passed to an optical block from an optical port and directed to a first one of multiple ports on an opposite surface of the optical block.
  • a wavelength sub-range which is "in-band" of such first one of the multiple ports is transmitted through that port by a local portion of a continuous, variable thickness interference filter.
  • the light not transmitted is reflected to strike a second port at which a second wavelength band is transmitted and all other light reflected.
  • Interference filters also known as Fabry-Perot filters or cavity filters
  • Interference filters typically consist of multiple stacked layers of dielectric material having alternating high and low refraction index. Groups of high/low index layers having optical thickness of one quarter wavelength of the filter band center are separated by one or more cavities. The cavities have an optical thickness equal to a multiple of one-half the wavelength of the filter band center. The center wavelength of the filter is passed by the filter while frequencies outside the in- band range are rejected by reflective interference.
  • interference filters for de-multiplexing an optical WDM signal
  • the in-band range of wavelengths passed by these filters tends to vary with the temperature of the filter because the optical thickness of the filter layers change with temperature.
  • the primary causes of this behavior are differences in thermal expansion of the filter materials, and the variations of the index of refractions of the materials with temperature. Accordingly, optical path lengths within the filter, upon which interference depends, tend to vary with temperature.
  • the band center can drift with changes in humidity.
  • an optical de-multiplexer in a location, such as an outdoor enclosure, where environmental temperature varies over a wide range. Due to their temperature intolerance, use of interference filters under such conditions may result in channel cross-talk if the temperature dependencies are not adequately compensated.
  • interference filters tend to introduce an ever-increasing amount of dispersion into the data signal as the passband becomes narrower. As such, there is a limit on how narrow the passband can become before data integrity is lost.
  • U.S. Patent No. 5,467,418 to Dragone discloses a frequency routing device having a spatially filtered optical grating.
  • a plurality of unequal length waveguides provide path length differences between input and output ports so as to function as a multiplexer or de-multiplexer of optical frequencies.
  • Such a waveguide device has a disadvantage in that the path lengths can vary due to thermal expansion. As a result, the passband for each channel can vary with changes in temperature.
  • U.S. Patent No. 5,938,811 to Greene also discloses use of an optical waveguide device, but attempts to compensate for temperature variations by incorporating within lengths of the waveguides a transparent compensating material.
  • the compensating material has a refractive index variation with temperature that differs substantially from that of the waveguide.
  • U.S. Patent 5,206,920 to Cremer et al. discloses an integrated optical arrangement for de-multiplexing different wavelength channels which uses a diffraction grating and waveguides.
  • a plurality of different wavelength channels are coupled to a film waveguide at an infeed point.
  • the channels are conducted to the diffraction grating which spatially separates the channels to different outfeed points.
  • Arrayed waveguide devices have, in the past, experienced low process yields, particularly as the channel spacing is reduced, and typically do not attempt to compensate for thermal expansion.
  • the arrayed waveguide devices tend to have greater insertion loss than the filters. As more channels are added to arrayed waveguide devices, the processing difficulties increase rapidly and costs tend to escalate.
  • Fiber Bragg gratings built into the fiber itself by an interference pattern are proposed as a possible solution, but they can be even more difficult to fabricate than the interference filters and arrayed waveguides discussed above.
  • the invention is an optical wavelength division multiplexer and de-multiplexer.
  • the multiplexer apparatus includes a spectrometer for combining various wavelengths of optical communication signals which are spatially separate into a single optical fiber which carries all of the signals simultaneously.
  • a spectrometer spatially separates the various wavelengths of light from the optical fiber carrier.
  • the multiplexer and de-multiplexer may be referred to collectively as "multiplexing devices.”
  • the multiplexing devices may utilize macroscopic or microscopic dispersive and focusing optical devices; a small "solid state" macro-optic spectrometer device is disclosed along with an even smaller, micro-optic spectrometer device.
  • the micro-optic device may be fabricated using semiconductor type lithographic and etching techniques.
  • dispersive optical devices By using dispersive optical devices to spatially separate (and to combine) optical signals and by constructing the devices from materials having the same or similar thermal expansion characteristics, problems associated with temperature intolerance of prior devices based on interference filters or waveguides are avoided.
  • an optical de-multiplexing device comprises an integrated optically transmissive body.
  • a first optical element on the body receives an optical signal including a plurality of wavelengths and spatially disperses the signal into a plurality of constituent signals according to wavelength.
  • a second optical element on the body intercepts the constituent signals from the first optical element and reflects the constituent signals away from the second optical element.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element and reflects the constituent signals away from the third optical element.
  • a fourth, optical element on the body intercepts the constituent signals reflected from the third optical element and focuses the constituent signals at a plurality of respective focal positions.
  • an optical multiplexing device comprises an integrated optically transmissive body.
  • a plurality of spatially separate constituent optical signals are directed toward the body.
  • a first optical element on the body focuses the constituent signals.
  • a second optical element on the body intercepts the constituent signals from the first optical element and reflects the constituent signals away from the second optical element.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element and reflects the constituent signals away from the third optical element.
  • a fourth optical element on the body receives the plurality of constituent signals reflected from the third optical element and spatially combines the constituent signals.
  • an optical multiplexing device comprises an integrated optically transmissive body. A plurality of spatially separate constituent optical signals are directed toward the body.
  • a first optical element on the body focuses the constituent signals.
  • a second optical element on the body intercepts the constituent signals from the first optical element and reflects the constituent signals away from the second optical element.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element, reflects the constituent signals away from the third optical element and spatially combines the constituent signals into an optical signal including a plurality of wavelengths.
  • a fourth optical element on the body receives the optical signal reflected from the third optical element and focuses the optical signal onto an optical fiber.
  • an optical multiplexing device comprises an integrated optically transmissive optical body.
  • a first optical element on the body receives an optical signal including a plurality of wavelengths and collimates the optical signal.
  • a second optical element on the body intercepts the optical signal from the first optical element, reflects the optical signal away from the second optical element and spatially disperses the signal into a plurality of constituent signals according to wavelength.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element and focuses the constituent signals at a plurality of respective focal positions.
  • an optical demultiplexing device comprises an integrated optically transmissive optical body.
  • a first optical element on the body receives an optical signal including a plurality of wavelengths and collimates the optical signal.
  • a second optical element on the body intercepts the optical signal from the first optical element, reflects the optical signal away from the second optical element and spatially disperses the signal into a plurality of constituent signals according to wavelength.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element and reflects the constituent signals away from the third optical element.
  • a fourth optical element on the body intercepts the constituent signals reflected from the third optical element and focuses the constituent signals at a plurality of respective focal positions.
  • an optical multiplexing device comprises an integrated optically transmissive body.
  • a plurality of spatially separate constituent optical signals are directed toward the body.
  • a first optical element on the body focuses the constituent signals.
  • a second optical element on the body intercepts the constituent signals from the first optical element and reflects the constituent signals away from the second optical element.
  • a third optical element on the body intercepts the constituent signals reflected from the second optical element, reflects the constituent signals away from the third optical element and spatially combines the constituent signals into an optical signal including a plurality of wavelengths.
  • a fourth optical element on the body receives the optical signal reflected from the third optical element and focuses the optical signal onto an optical fiber.
  • an optical demultiplexing device comprises a main body prism element having a long face and first and second short faces.
  • a wedge prism element is coupled to the long face of the main body prism element.
  • a first lens is coupled to the wedge prism element for receiving an optical signal including a plurality of wavelengths and for collimating the optical signal.
  • An adjunct prism element has a long face and first and second short faces. The long face of the adjunct prism element is coupled to a first short face of the of the main body prism element. The adjunct prism element receives the optical signal from the first lens via the main body prism element.
  • a diffraction grating element is coupled to the first short face of adjunct prism element for spatially dispersing the signal into a plurality of constituent signals according to wavelength and for reflecting the plurality of constituent signals toward the long face of the main body prism element via the long face of the adjunct prism element.
  • a second lens is coupled to the second short face of the main body prism element for focusing the plurality of constituent signals.
  • optical multiplexing devices are provided.
  • An optically transmissive substrate has first and second surfaces which are substantially parallel to each other. A first array of optical elements is formed on the first surface. A second array of optical elements is formed on the second surface. The substrate is separable into individual optical multiplexing devices.
  • Each individual optical multiplexing device includes at least one optical element from the first array and at least one optical element from the second array.
  • the optical elements of each optical multiplexing device form a contiguous optical path. Light which travels along the contiguous optical path is collimated, spatially dispersed and focused by the optical elements of the corresponding optical multiplexing device.
  • a coupling element provides appropriate separation between fiber cables for each channel and is utilized to fasten the fiber cables to the dispersive and focusing optical elements of the multiplexer and de-multiplexer devices.
  • the fiber cables are located in an appropriate position for each channel. Effects of thermal expansion are negated by providing that the coupling element is formed of a material which has substantially the same thermal expansion behavior as the diffraction and focusing elements. Accordingly, all of the elements in the optical path for each of the channels expand and contract with temperature variations in the same manner, thus, preserving their spatial relationships. Because interference filters and waveguides are avoided, separation of channels does not depend on precisely dimensioned optical path lengths.
  • the devices of the present invention are particularly suited for use in dense wavelength division multiplexing (DWDM).
  • DWDM dense wavelength division multiplexing
  • Other advantages include small packaging size, simplified connection of the output channels directly to the photodiode detectors in some cases, and ability to automate production of the assembly. These devices permit more economical production of DWDM systems for use in fiber optic communication equipment and allow channels to be packed more densely.
  • FIG. 1 illustrates a side sectional view of a macro-optics wavelength division multiplexing (WDM) device in accordance with the present invention
  • Figure 2a illustrates a side sectional view of a micro-optics WDM device in accordance with the present invention
  • Figure 2b illustrates a perspective view of a section of a planar substrate upon which a number of the micro-optics devices of Figure 2a may be processed before separation into individual devices;
  • Figures 3a-3b illustrate enlarged side and top views, respectively, of a coupling element for fastening fiber optic cables to the micro-optics WDM device of Figure 2a;
  • Figures 4a-4b illustrate enlarged side and top views, respectively, of an alternate embodiment of a coupling element for fastening fiber optic cables to the micro-optics WDM device of Figure 2a;
  • Figure 5 illustrates a perspective view of the micro-optics WDM device of Figure 2 along with the coupling element of Figures 3a-b;
  • Figure 6 illustrates a perspective view of the micro-optics WDM device of Figure 2 along optical detectors (e.g., photodiodes);
  • optical detectors e.g., photodiodes
  • Figure 7 illustrates a side sectional view of a first alternate embodiment of a micro-optics WDM device in accordance with the present invention
  • Figure 8 illustrates a side sectional view of a second alternate embodiment of a micro-optics WDM device in accordance with the present invention
  • Figure 9 illustrates a side sectional view of a third alternate embodiment of a micro-optics WDM device in accordance with the present invention.
  • Figure 10 illustrates a side sectional view of an alternate embodiment of a macro-optics WDM device in accordance with the present invention. Detailed Description of a Preferred Embodiment
  • WDM wavelength division multiplexing
  • DWDM dense wavelength division multiplexing
  • the macroscopic devices may be difficult to miniaturize below some size.
  • the macro-optic devices demonstrate the principles upon which the microscopic designs (referred to herein as "micro-optics") also function.
  • Figure 1 illustrates a side sectional view of a macro-optics WDM device 1 in accordance with the present invention.
  • the section of the drawing corresponds to the plane in which the light is dispersed (i.e. in which the light is wavelength divided or de-multiplexed).
  • the dimensions of device 1 in the direction perpendicular to the plane of the sectional view, i.e. the plane of the paper, may be relatively thin in comparison to the dimensions of the place of the sectional view.
  • An input fiber 8 contains optical signals of different wavelengths present simultaneously, designated as ⁇ (i throu h n)-
  • the number n of multiplexed or de-multiplexed optical signals may range from two to an arbitrarily large number, depending upon the number of channels.
  • the signals ⁇ (i through n) are shown separated spatially by a dispersive element 5 into constituent wavelengths ⁇ i through ⁇ n .
  • Light may be directed through the device 1 in an opposite direction for combining (i.e. multiplexing) the wavelength signals ⁇ i through ⁇ n onto the single fiber 8.
  • the device 1 of Figure 1 maybe constructed with commercially available, off- the-shelf, optical components.
  • a first 90-degree symmetrical prism element 2 may provide a main body for the device 1.
  • the prism element 2 may have dimensions of approximately 10 to 20 mm along each face.
  • a second, smaller, 90- degree symmetrical prism element 3 may have its long face coupled to a first short face of the prism element 2, as shown in Figure 1.
  • a reflective diffraction grating element 5 may be coupled to a short face of the adjunct prism element 3 for dispersing the combined signals ⁇ ( i throu g h n) into constituent wavelengths ⁇ i through ⁇ n .
  • the long face of the prism element 2 and the short face of the prism element 3, to which the grating element 5 is coupled may be substantially parallel.
  • a wedge prism element 4 may be coupled to the long face of the main body prism element 2 for providing the necessary incidence angle for the grating element 5 so that the combined signals ⁇ ( i throu g h n) strike the grating element 5 at an appropriate angle.
  • a lens element 6 may be coupled to a side of the wedge prism element 4 opposite the prism element 2 so as to collimate the combined signals ⁇ (i t hrou g h n) prior to the signals ⁇ (i through n) striking the grating element 5.
  • a lens element 7 may be coupled to a second short face of the body prism element 2 so as to receive and focus the signals ⁇ i tlirough ⁇ n which are spatially separated by the grating element 5. The lens element 7 may focus the separate signals ⁇ i through ⁇ n onto optical fibers or optical detectors.
  • the combined signals ⁇ (i th r ou h n) may be delivered to the lens 6 via the fiber cable 8.
  • the lens 6 collimates the signals ⁇ (i through n).
  • the collimated signals ⁇ through n) then pass from the lens 6 through the wedge element 4.
  • the signals ⁇ ( i throu g h n) enter the long face of the prism element 2 and exit the first short face of the prism element 2, where they enter the long face of the prism element 3.
  • the signals ⁇ ( i throu g h n ) travel within the prism element 3 and, then, strike the reflective grating element 5 at short face of the prism element 3.
  • the signals ⁇ are then spatially dispersed by the grating element 5 into the separate signals ⁇ i through ⁇ n which are reflected back through the long face of the prism element 3 and into the prism element 2 via its first short face.
  • the signals ⁇ i through ⁇ n are then internally reflected from the long face of the prism element 2 and exit the prism element 2 at its second short face. Because the dispersed signals ⁇ i through ⁇ n are preferably totally internally reflected from a portion of the long face of the prism element 2, a reflective coating may be formed on that portion of the prism element 2.
  • the signals ⁇ i through ⁇ n pass through the lens element 7 which focuses the signals ⁇ i through ⁇ ,,.
  • the signals ⁇ i through ⁇ n emerge from the lens element 7 at respective focal positions which are spatially separated, as shown in Figure 1.
  • the signals ⁇ ⁇ through ⁇ n may be received by photodetectors (not shown) mounted directly at the respective focal positions or by optical fibers (not shown). The optical fibers may then deliver the signals ⁇ i through ⁇ n to photodetectors which are mounted at locations other than the focal positions.
  • light sources such as laser sources (not shown)
  • laser sources for the various different wavelengths ⁇ ⁇ through ⁇ n
  • Graded index (GRIN) lenses may be utilized to transfer the signals from the laser sources to the device 1.
  • the signals ⁇ ] through ⁇ n may be delivered to the lens element 7 via fiber cables (not shown) mounted at the respective focal positions.
  • the signals ⁇ i tlirough ⁇ n then enter the lens element 7 and travel in a direction opposite to that previously described so as to emerge from the device 1 tlirough lens 6.
  • the signals ⁇ i through ⁇ n may be combined by the grating element 5 into the signals ⁇ (i through n).
  • the signals ⁇ (j throug h n) are then focused onto the optical fiber 8 by the lens element 6.
  • the elements 2-7 are bonded together using an adhesive that has an optical index which substantially matches that of the prism elements 2-4 so that elements 2-4 function optically as a single integrated unit (e.g., without internal reflections along the boundaries between them).
  • one or more of the elements 2-7 may be integrally formed such that cement is not necessary to bond such elements together.
  • the lenses 6 and 7 may be simple lenses. Alternately, the lenses 6 and 7 may be compound so as to eliminate or reduce certain optical aberrations.
  • one of the prism elements 2 or 3 may be modified to produce the required angle of incidence for the grating element 5.
  • the wedge prism 4 may be eliminated.
  • the prism element 2 may be elongated to include a central rectangular portion.
  • the number of internal reflections of the signals ⁇ i through ⁇ n may be increased. This leads to an increase in the spatial separation of the signals ⁇ i through ⁇ n .
  • the diameter of lens 7 may be increased appropriately to intercept all of the signals ⁇ i through ⁇ n . It will be apparent that other variations are possible.
  • the scale of the device 1 is limited by the size of available macro-lenses and other optical elements. Presently, lenses on the order of a millimeter in diameter are readily obtainable.
  • Figure 2a illustrates a side sectional view of a micro-optics WDM device 9 in accordance with the present invention.
  • the section of the drawing corresponds to the plane in which the light is dispersed.
  • An input fiber 18 contains optical signals of different wavelengths present simultaneously, designated by ⁇ ( i throu g h n
  • the number n of multiplexed or de-multiplexed optical signals may range from two to an arbitrarily large number, depending upon the number of channels.
  • the signals ⁇ (i thr ou g h n ) are separated spatially by a dispersive elements 12 and 13 into constituent wavelengths ⁇ i through ⁇ n .
  • Light may be directed through the device 9 in an opposite direction for combining (i.e. multiplexing) the signals ⁇ i through ⁇ n onto the single fiber 18.
  • the micro-optic device 9 of Figure 2a may have a lengthwise dimension of, for example, a few millimeters to a few tens of millimeters and may be formed using an optically transmissive (e.g., transparent) planar substrate 11 (e.g., quartz) having substantially parallel top and bottom surfaces.
  • the substrate 11 may be patterned using photo-lithography, etching, and thin film deposition techniques with two micro- diffraction and focusing optical elements 12 and 13. After exposing and developing photoresist patterns, the substrate 11 may be etched to form the patterns 12, 13 at predetermined locations.
  • the optical elements such as elements 12, 13, from the substrate 11, the device 9 becomes an integrated body.
  • the effects of thermal expansion affect each dimension of device 9 proportionately so that spatial relationships are maintained despite changes in temperature.
  • many devices may be etched upon a single substrate or wafer and then separated into individual devices or into groups of devices.
  • FIG. 2b illustrates this planar substrate (i.e. wafer) processing.
  • Element 10 is a portion of a planar substrate which, for convenience, may be round, square, or some other shape.
  • Micro-optics elements may be formed on top and bottom surfaces of the wafer, h Figures 2b, element 14 is illustrated as a combination mirror and planar diffractive grating. It is apparent in this perspective view that device 9 has a width which only needs to be slightly greater than the diameter of collimating (and diffracting) element 12.
  • the diffraction optical elements 12, 13 may each perform multiple functions.
  • each may act as a lens (or as a focusing mirror if coated with a reflective material) to focus the light.
  • each of the diffraction elements 12, 13 may incorporate a grating structure to disperse the light according to wavelength. Alternately, additional optical elements may be provided to accomplish these functions separately. In addition, neither of the elements 12, 13 need be dispersive of light if that function is performed separately. Element 12 and any other element that transmits the signals preferably, though not necessary, has an anti-reflection coating to reduce signal loss.
  • Mirrors 14 and 15 may be formed by thin film deposition techniques.
  • the regions 14, 15 may be formed, for example, by applying layers of protected silver or highly reflective alternating layers of high and low index dielectric materials.
  • they may be made to double as diffracting elements to obtain increased wavelength separation or to serve the diffraction function of another element, like element 12, for example.
  • a reflective coating may also be applied to the diffraction element 13 so that it will also function as a mirror in addition to its focusing and dispersive qualities.
  • Various different multiplexed wavelength signals ⁇ may be directed toward the diffraction element 12 by the fiber cable 18. As the signals ⁇ (i throu g h n) pass through the element 12, they enter the substrate 11 of the device 9.
  • the diffraction element 12 may collimate and also disperse the signals ⁇ (i through n) into spatially separate constituent signals ⁇ i through ⁇ n .
  • element 12 preferably has a light acceptance angle which substantially matches the numerical aperture of optical fiber 18.
  • the signals ⁇ ] through ⁇ n then travel within the device 9 toward the opposite side of the substrate 11 from which they may be reflected by the region 14.
  • the reflective region 14 may be located on a side of the substrate 11 opposite the diffraction element 12.
  • the signals ⁇ i through ⁇ n then travel within the device 9 back toward the other side of the substrate 11.
  • the signals ⁇ i through ⁇ n may then be reflected by the region 15.
  • the reflective region 15 is located on the same side of the substrate 11 as the diffraction element 12 and adjacent to the element 12.
  • the signals ⁇ ⁇ through ⁇ n travel within the device 9 back toward the side of the substrate 11 on which the reflective region 14 is fonned.
  • the signals ⁇ i through ⁇ n may then strike the diffraction element 13.
  • the element 13 may be located on the same side of the substrate 11 as the reflective region 14 and adjacent to the region 14.
  • the element 13 may provide further separation of the signals ⁇ i through ⁇ n by diffraction. Further, the element 13 may reflect the signals ⁇ i through ⁇ n back toward the side of the substrate 11 on which the diffraction element 12 and the reflective region 14 are located.
  • each of signals ⁇ i through ⁇ n may emerge from the substrate 11 adjacent to the reflective region 14 in spatially separated positions where each signal may be received by a respective one of fiber optic cables 17.
  • the element 13 may focus the signals ⁇ i tlirough ⁇ n onto the respective cables 17.
  • the signals ⁇ i tlirough ⁇ n may be allowed to exit the substrate 11 through the diffraction element 13. This may be accomplished by omitting the reflective layer from the element 13. In which case, the cables 17 may be positioned to receive the spatially separate signals ⁇ i through ⁇ n at appropriate positions on the side of the substrate 11 opposite their positions shown in Figure 2.
  • Coupling element 16 provides a support structure for the optical fibers 17.
  • Figures 3a-3b illustrate enlarged side and top views, respectively, of a first embodiment of the coupling element 16.
  • the coupling element 16 may include grooves 19 which accept the optical fibers 17.
  • Figure 3b shows cross sections of the fibers 17 inserted into the grooves 19.
  • the coupling element 16 may be formed of a block of material that has been accurately etched so as to form the grooves 19 to which the optical fibers 17 are placed. This block may then be polished with the fibers 17 attached to form a smooth interface between the coupling element 16 and the substrate 11.
  • FIGs 4a-b illustrate enlarged side and top views, respectively, of an alternative embodiment of the coupling element 16 (designated 16').
  • V- shaped grooves 19' are used as a convenient way to permit fiber cables 17 to be placed close together. Since the numerical aperture of optical fibers is relatively large, parallel grooves 19' may function adequately in a pickup mode, or they may be angled with respect to each other, as shown in the figure. This embodiment may allow the device 9 ( Figure 2a) to support an increased channel density.
  • Figure 5 illustrates a perspective view of the micro-optics WDM device 9 of
  • the coupling element 16 may be mounted such that its side is substantially perpendicular to the top planar surface of the device 9.
  • the coupling element 16 may be mounted on the opposite side (i.e. the bottom surface) of the substrate 11.
  • the fiber cables 17, which are aligned with the grooves 19 the side of the coupling element 16 are mounted in the plane in which the signals are dispersed (i.e., the sectional plane of Figure 2).
  • Coupling element 16 may be bonded to the substrate 11 using an optical index matching adhesive.
  • the coupling element 16 is formed of a material which has a similar coefficient of thermal expansion to that of the substrate 11.
  • the coupling element 16 may be formed of the same material as the substrate 11 ( Figure 2a).
  • the coupling element 16 is also preferably formed of quartz.
  • the coefficient of thermal expansion for the coupling element 16 and the substrate 11 is identical.
  • the coupling element 16 may be formed of another material, such as silicon.
  • the etching of V-shaped grooves, as shown in Figures 4a-b, in a silicon wafer with ⁇ 100 ⁇ crystallographic orientation may be accomplished in accordance with conventional semiconductor processing techniques.
  • the coupling element 16 By forming the coupling element 16 of a material which has a similar coefficient of thermal expansion as the substrate 11, and the entire structure expands and contracts together with changes in temperature, while maintaining optical alignment between the fibers 17 and the optical elements, such as the dispersive elements 12 and 13.
  • the fibers 17 may be routed to light sources, such as laser sources. Alternately, graded index (GRIN) lenses could be used to transfer the signals.
  • the fibers 17 may be routed to optical detectors (not shown).
  • optical detectors 20, such as photodiodes may be mounted directly to the substrate 11 to detect the signals, as shown in Figure 6. In which case, the coupling element 16 can be omitted. By mounting the detectors 20 directly to the substrate 11, thermal expansion and contraction of the substrate 11 will cause the spacing between the detectors 20 to expand and contract proportionately. Accordingly, appropriate spatial relationships are maintained by the arrangement of Figure 6 despite changes in temperature.
  • a Kinoform grating can be etched with a diffractive lens element to add dispersion to its functionality.
  • the dispersion function of such a lens may have a blaze efficiency of approximately 80%, corresponding to a loss of about 1.0 db.
  • the blaze efficiency may improve to approximately 95%, corresponding to a loss of only 0.25 db.
  • Interference filters have insertion losses that range from about 0.3 db for wideband response to about 1 db for the narrowband response.
  • Current versions of arrayed wave guide devices have much higher insertion losses, in the range of 8 to 9 db.
  • the diffractive element or elements are not also focusing or collimating, they may be formed as ruled or holographic diffraction grating types.
  • Mechanically ruled gratings have high efficiency because their grooves have sharp edges. However, such gratings tend to be expensive and difficult to fabricate.
  • the gratings may also be etched, however, masking required for etching may be difficult.
  • the gratings may be holographic gratings which are formed by exposing photoresist to laser interference fringes. The sinusoidally-shaped grooves which result from the holographic process may be somewhat less efficient than sharp grooves formed by other processes, however, their economy and simplicity may justify their use.
  • the number of channels is determined by the amount of diffraction provided by the micro-optics elements and the spacing of the optical fiber cables on the coupling element 16 (or the packing density of photodetectors along the same focal plane).
  • the coupling element 16 can support about eight channels per millimeter of length. Therefore, a hundred or more channels on a single device is readily obtainable with standard 125 micrometer diameter fibers.
  • the device 9 could easily be made slightly larger to accommodate more channels, or the fiber optic cable could be made smaller in diameter. In particular, single mode fibers with only a 10 micrometer core diameter could be made with thinner cladding.
  • mirror 15 could be omitted, with element 13 placed approximately in its position. Then coupling element 16 would be placed approximately where element 13 is in Figure 2a.
  • Figure 7 designated device 9'.
  • the reflective element 14 may be replaced by a reflecting and diffracting element 14'.
  • a result of the arrangement of Figure 7 may be somewhat less spatial separation of the optical channels since there is only one element with a diffraction function (i.e. the element 14').
  • the device 9' may support fewer channels that are separated farther apart in wavelength.
  • such a device would still be very useful and economically beneficial.
  • micro-optic elements on the two sides of the substrate 11, follows the same design principles, but may result in more or fewer channels that the device 9' can support.
  • the details of the layout of the elements may be chosen to most appropriately support the particular requirements at hand.
  • a further modification to the device 9' of Figure 7 may include eliminating the diffractive function of element 12 such that it only collimates the light.
  • Figure 8 shows a device 9" which is similar to the device 9 of Figure 2a except that the dispersive functions are separated from the lens collimating and focusing functions and added to the reflective functions. Accordingly, the lenses 12 and 13 of Figure 2a need not be dispersive in the device 9" of Figure 8. Instead, non-dispersive, diffractive lenses 12' and 13' may be substituted. In addition, reflective elements 14 and 15 of Figure 2a may also be dispersive in Figure 8. Thus, the elements 14" and 15" of Figure 8 are reflective and dispersive.
  • the lens element 12' collimates the combined signals ⁇ (i t hr o ug h n ) from an input fiber optic cable 18.
  • the signals ⁇ ( i throu g h n) enter the substrate 11 at the lens 12' and travel toward the opposite side of the substrate 11 where the grating element 14" is located.
  • the signals ⁇ (i through n) are then dispersed by the grating element 14" and reflected back toward the opposite side of the subsfrate 11.
  • the spatially separated signals ⁇ i through ⁇ n then strike the grating element 15" which further disperses them.
  • the signals ⁇ i through ⁇ n are internally reflected by the grating element 15" back toward the other side of the substrate 11 where the reflective lens element 13' is located.
  • the reflective lens element 13' focuses the signals ⁇ i through ⁇ n and internally reflects them back toward the side of the substrate 11 on which the lens element 12' and grating element 15" are located.
  • the signals ⁇ i through ⁇ n then emerge from the substrate 11 adjacent to the grating element 15".
  • the signals ⁇ i tlirough ⁇ n are then coupled to fibers or detectors as described in reference to the device 9 of Figures 2a, 5 and 6.
  • FIG. 9 Another example of a micro-optics approach in accordance with the present invention is illustrated by device 9'" in Figure 9.
  • the device 9"' of Figure 9 is similar to the device 9" of Figure 8 except that the lenses 12" and 13" of Figure 9 may each be formed by etching away the surface of the substrate 11 to leave small lenses (also known as "micro-lenses"). These lenses are identical in shape to conventional glasses lenses, but may be very small (e.g., sub-millimeter diameter) as in the case of the lens 12" or may be a segment of a larger lens, as in the case of lens 13".
  • the device 9 in Figure 2a utilizes combined lenses and diffraction optics in elements 12 and 13.
  • the device 9' in Figure 7 largely results from the device in Figure 2a if elements 12 and 13 are changed to conventionally shaped micro-lenses and mirrors 14 and 15 are changed to reflective diffraction gratings. Angles between elements may also be easily modified to achieve a particular result, all within the scope of the guidelines herein described.
  • FIG. 10 Another example of a macro-optics approach in accordance with the present invention is- illustrated by device 30 in Figure 10.
  • the device 30 is similar to the device 1 shown in Figure 1.
  • a prism 31 need not be a symmetrical 90 degree prism, as in Figure 1.
  • the prism 31 of Figure 6 is rhomboidal. Angles of the rhomboidal prism 31 may be selected to accommodate a focusing concave mirror 32.
  • the spatially separated signals ⁇ i through ⁇ n are reflected back within the device 30 by the focusing mirror 32.
  • the signals ⁇ i through ⁇ n then emerge from the device 30 of Figure 10 along a flat, top face 33 of the prism 31 where they are coupled to fibers or detectors in the fashion described above in reference to the device 1 in Figure 1.
  • the device 30 of Figure 10 may also be utilized as a multiplexer.
  • the spatially separate wavelength signals ⁇ i through ⁇ n may be delivered to the device 30 at the focal positions of the lens element 32.
  • the combined signals ⁇ (i throu g h n) niay then emerge from the micro lens 32 where they are received by the fiber cable 8.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

L'invention concerne un multiplexeur et un démultiplexeur en longueur d'onde optique (1). Ce multiplexeur (1) combine différentes longueurs d'ondes de signaux de communication optique séparés spatialement pour former une fibre optique porteuse. Le démultiplexeur (1) sépare les différentes longueurs d'onde. Cet appareil (1) peut utiliser des dispositifs optiques (5) de dispersion et de focalisation macro-optiques ou micro-optiques. Ces dispositifs micro-optiques peuvent être fabriqués par des techniques de lithographie et de gravure de type semi-conducteur. L'utilisation de dispositifs optiques (5) de dispersion permet de séparer spatialement (et de combiner) des signaux optiques et la fabrication de ces dispositifs à partir de matériaux présentant des caractéristiques de dilatation thermique identiques ou similaires permet d'éviter les problèmes liés à l'intolérance thermique présents dans les dispositifs antérieurs sur la base de filtres interférentiels ou de guides d'ondes. Un élément d'assemblage fournissant une séparation appropriée entre les câbles des fibres de chaque canal est utilisé pour fixer les câbles à des éléments optiques de dispersion et de focalisation. Les effets de la dilatation thermique sont inversés si l'élément d'assemblage est formé à partir d'un matériau présentant sensiblement la même dilatation thermique que les éléments de diffraction et de focalisation. Par conséquent, chaque élément du parcours optique de chacun des canaux se dilate et se contracte de la même manière avec les variations de température, ce qui permet à chaque élément de conserver ses rapports spatiaux. Puisque les filtres interférentiels et les guides d'ondes ne sont pas utilisés, la séparation des canaux ne dépend pas de longueurs de parcours optiques précisément dimensionnés.
PCT/US2001/015129 2000-05-09 2001-05-09 Multiplexeur et demultiplexeur en longueur d'onde optique WO2001086848A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US56856600A 2000-05-09 2000-05-09
US09/568,566 2000-05-09

Publications (1)

Publication Number Publication Date
WO2001086848A1 true WO2001086848A1 (fr) 2001-11-15

Family

ID=24271800

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/015129 WO2001086848A1 (fr) 2000-05-09 2001-05-09 Multiplexeur et demultiplexeur en longueur d'onde optique

Country Status (1)

Country Link
WO (1) WO2001086848A1 (fr)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7081955B2 (en) 2003-05-28 2006-07-25 Hamamatsu Photonics K.K. Photodetector and spectrometer using the same
EP1863189A2 (fr) 2001-05-30 2007-12-05 LG Electronics Inc. Système de commande de réseau pour appareils domestiques
WO2008135515A1 (fr) * 2007-05-04 2008-11-13 Thales Dispositif et procede de calibration d'une source lumineuse
WO2013017457A1 (fr) * 2011-08-02 2013-02-07 Carl Zeiss Microscopy Gmbh Spectromètre
EP2615435A1 (fr) * 2012-01-10 2013-07-17 austriamicrosystems AG Élément dispersif, spectromètre et procédé pour séparer spectralement des longueurs d'ondes de la lumière incidente sur un élément dispersif
WO2014001074A1 (fr) * 2012-06-27 2014-01-03 Nico Correns Système spectrométrique monolithique
EP2715951A4 (fr) * 2011-05-23 2015-04-22 Hewlett Packard Development Co Système d'émission optique
EP2896941A1 (fr) * 2014-01-21 2015-07-22 ams AG Élément dispersif pour spectromètre et spectromètre
CN104880773A (zh) * 2015-05-26 2015-09-02 苏州旭创科技有限公司 波分复用解复用装置及光模块
CN108333688A (zh) * 2018-02-07 2018-07-27 江苏奥雷光电有限公司 用于自由空间光传播的波分复用解复用光器件
CN108897101A (zh) * 2018-07-23 2018-11-27 上海航天科工电器研究院有限公司 一种自由空间光传输的波分复用/解复用光波导组件
WO2019129798A1 (fr) * 2017-12-29 2019-07-04 Universiteit Gent Filtre insensible à la température
DE102009018262B4 (de) 2008-06-26 2019-10-24 Northrop Grumman Space & Mission Systems Corporation Verfahren und System zum spektralen Bündelvereinigen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4744618A (en) * 1982-05-03 1988-05-17 Siemens Aktiengesellschaft Optical device for use as a multiplexer or demultiplexer in accordance with the diffraction grating principle
US6008920A (en) * 1998-03-11 1999-12-28 Optical Coating Laboratory, Inc. Multiple channel multiplexer/demultiplexer devices
US6219473B1 (en) * 1997-06-09 2001-04-17 Jobin Yvon Sa Optical fiber wavelength multiplexer-demultiplexer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4744618A (en) * 1982-05-03 1988-05-17 Siemens Aktiengesellschaft Optical device for use as a multiplexer or demultiplexer in accordance with the diffraction grating principle
US6219473B1 (en) * 1997-06-09 2001-04-17 Jobin Yvon Sa Optical fiber wavelength multiplexer-demultiplexer
US6008920A (en) * 1998-03-11 1999-12-28 Optical Coating Laboratory, Inc. Multiple channel multiplexer/demultiplexer devices

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1863189A2 (fr) 2001-05-30 2007-12-05 LG Electronics Inc. Système de commande de réseau pour appareils domestiques
US7081955B2 (en) 2003-05-28 2006-07-25 Hamamatsu Photonics K.K. Photodetector and spectrometer using the same
WO2008135515A1 (fr) * 2007-05-04 2008-11-13 Thales Dispositif et procede de calibration d'une source lumineuse
DE102009018262B4 (de) 2008-06-26 2019-10-24 Northrop Grumman Space & Mission Systems Corporation Verfahren und System zum spektralen Bündelvereinigen
US9331782B2 (en) 2011-05-23 2016-05-03 Hewlett Packard Enterprise Development Lp Optical transmission system
EP2715951A4 (fr) * 2011-05-23 2015-04-22 Hewlett Packard Development Co Système d'émission optique
WO2013017457A1 (fr) * 2011-08-02 2013-02-07 Carl Zeiss Microscopy Gmbh Spectromètre
EP2615435A1 (fr) * 2012-01-10 2013-07-17 austriamicrosystems AG Élément dispersif, spectromètre et procédé pour séparer spectralement des longueurs d'ondes de la lumière incidente sur un élément dispersif
US8873047B2 (en) 2012-01-10 2014-10-28 Ams Ag Dispersive element, spectrometer and method to spectrally separate wavelengths of light incident on a dispersive element
US9625317B2 (en) 2012-06-27 2017-04-18 Nico Correns Monolithic spectrometer arrangement
WO2014001074A1 (fr) * 2012-06-27 2014-01-03 Nico Correns Système spectrométrique monolithique
WO2015110292A1 (fr) * 2014-01-21 2015-07-30 Ams Ag Élément dispersif pour un spectromètre, et spectromètre
EP2896941A1 (fr) * 2014-01-21 2015-07-22 ams AG Élément dispersif pour spectromètre et spectromètre
CN104880773A (zh) * 2015-05-26 2015-09-02 苏州旭创科技有限公司 波分复用解复用装置及光模块
WO2019129798A1 (fr) * 2017-12-29 2019-07-04 Universiteit Gent Filtre insensible à la température
US11360262B2 (en) 2017-12-29 2022-06-14 Universiteit Gent Temperature insensitive filter
CN108333688A (zh) * 2018-02-07 2018-07-27 江苏奥雷光电有限公司 用于自由空间光传播的波分复用解复用光器件
CN108333688B (zh) * 2018-02-07 2020-11-10 江苏奥雷光电有限公司 用于自由空间光传播的波分复用解复用光器件
CN108897101A (zh) * 2018-07-23 2018-11-27 上海航天科工电器研究院有限公司 一种自由空间光传输的波分复用/解复用光波导组件

Similar Documents

Publication Publication Date Title
US6201908B1 (en) Optical wavelength division multiplexer/demultiplexer having preformed passively aligned optics
US6212312B1 (en) Optical multiplexer/demultiplexer using resonant grating filters
US7085492B2 (en) Wavelength division multiplexed device
US6415080B1 (en) Echelle grating dense wavelength division multiplexer/demultiplexer
US6239891B1 (en) Optical demultiplexer and method of assembling same
US7483190B2 (en) Method and apparatus for implementing a multi-channel tunable filter
US6400509B1 (en) Apparatus and method for the reduction of polarization sensitivity in diffraction gratings used in fiber optic communications devices
EP1400047A2 (fr) Dispositif multiplexe par repartition en longueur d'ondes
US20020176126A1 (en) Method and apparatus for implementing a multi-channel tunable filter
WO2001086848A1 (fr) Multiplexeur et demultiplexeur en longueur d'onde optique
US20020044721A1 (en) Mems device having multiple DWDM filters
CA2245389A1 (fr) Multiplexeur-demultiplexeur pour signaux optiques mrl
US6343170B1 (en) Optical spectrum analyzer
JP4158895B2 (ja) 機能性光ファイバコネクタ
US7587112B2 (en) Optical device and light control method
JP2000131542A (ja) 光送受信モジュール
US20040086221A1 (en) Low cost, hybrid integrated dense wavelength division multiplexer/demultiplexer for fiber optical networks
EP0710870B1 (fr) Valve de lumière à cristal liquide à socle en silicium armorphe et sa méthode de fabrication
EP1228388A1 (fr) Reseaux de diffraction holographiques volumiques ou superposes pour multiplexage en longueur d'onde et spectroscopie
JP2000137138A (ja) 分波・合波手段を端部に備えた光ファイバ、及び分波・合波手段を受光面上にに備えた光検出装置
US20020131702A1 (en) Combined multiplexer and demultiplexer for optical communication systems
EP1338906A1 (fr) Guide d'onde integré routeur en frequence
EP1151331A1 (fr) Composants optiques
JPS6184611A (ja) 回折格子形光合波分波器

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA CN JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载