EP1290489A1 - Aiguilleur optique a base de modulateurs spatiaux de lumiere - Google Patents
Aiguilleur optique a base de modulateurs spatiaux de lumiereInfo
- Publication number
- EP1290489A1 EP1290489A1 EP01945455A EP01945455A EP1290489A1 EP 1290489 A1 EP1290489 A1 EP 1290489A1 EP 01945455 A EP01945455 A EP 01945455A EP 01945455 A EP01945455 A EP 01945455A EP 1290489 A1 EP1290489 A1 EP 1290489A1
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- European Patent Office
- Prior art keywords
- optical
- cell
- cells
- beams
- deflection
- 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.)
- Withdrawn
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0005—Switch and router aspects
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/32—Holograms used as optical elements
-
- 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
- G02B6/264—Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
- G02F1/31—Digital deflection, i.e. optical switching
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/08—Synthesising holograms, i.e. holograms synthesized from objects or objects from holograms
-
- 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
- G02B6/32—Optical coupling means having lens focusing means positioned between opposed fibre ends
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
- G02F1/292—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection by controlled diffraction or phased-array beam steering
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/02—Function characteristic reflective
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/12—Function characteristic spatial light modulator
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2203/00—Function characteristic
- G02F2203/22—Function characteristic diffractive
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/0005—Adaptation of holography to specific applications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0005—Switch and router aspects
- H04Q2011/0007—Construction
- H04Q2011/0026—Construction using free space propagation (e.g. lenses, mirrors)
Definitions
- the invention relates to a device capable of interconnecting two sets of optical fibers and relates primarily to the field of telecommunications equipment.
- Optical patching equipment is beginning to be used on an experimental basis in optical transport networks and should be deployed on a large scale in the coming years.
- the reconfigurable optical patching function allows, in a node of the WDM network, the establishment and reconfiguration of connections between incoming optical channels and outgoing optical channels.
- the reconfiguration of the brewers is ensured by network administration bodies.
- This possibility of reconfiguring optical cross-connects more generally makes it possible to pass from a juxtaposition of point-to-point WDM links to a true flexible optical layer whose granularity is the wavelength (or optical channel), that is to say - say 2.5 or 10 Gbit / s.
- This need for flexibility of the optical layer is linked in particular to the increase in Internet traffic and the need to manage the increasingly large WDM transmission capacities which result therefrom.
- this invention relates to all areas where the switching of optical beams is necessary.
- Switching matrices for optical crossovers have been produced in electronic technology.
- Several manufacturers (Tellium, Nortel, Ciena, Monterey Networks, Sycamore, Nexabit Networks) have announced products implementing this technology. All-optical brewing technologies are less advanced. They are transparent to the speed of each optical channel, and will therefore allow better scalability of the equipment in a multi-vendor and multi-speed environment. On the other hand, it is relatively clear that these technologies will only be able to impose themselves on the market if their cost is competitive compared to electronic technologies.
- thermo-optical matrices are also available, either in polymer technology (JDS) or in silica technology (NEL). Obtaining a number of ports greater than 16 remains problematic.
- Other integrated technologies such as Lithium Niobate or
- Indiu phosphide still requires significant development to arrive at high-performance and high-capacity matrices.
- Micro-mechanical devices on Silicon are studied for applications in optical mixing, mainly in the USA (AT&T, IMMI, OMM, Astarte, Lucent, Xros, ...) These implement switching matrices based micromirrors on silicon capable of deflecting an optical beam along two axes.
- a 576-port optical mixer was produced by Texas Instruments and Astarte.
- Lucent announced the marketing at the end of 2000 of a 'Wavestar lambda router', with 256 ports.
- Xros for its part presented a prototype of 1152 ports, with a marketing planned for the beginning of 2001.
- the use of micromirrors is particularly interesting from the point of view of insensitivity to the wavelength and independence to polarization.
- Liquid crystal technologies which have a good level of maturity for visualization applications, also offer interesting perspectives.
- NTT and France Télécom have carried out various demonstrations, by cascading several stages of liquid crystal cells and birefringent calcite crystals (for example 11 stages for 64 ports).
- liquid crystal devices offer only a small number of fibers to be connected.
- Liquid crystal switching devices have also been proposed deflecting the optical beams in two perpendicular dimensions.
- the proposed devices are bulky because the means of diversion must be powerful.
- the invention proposes, primarily, to overcome this drawback, that is to say to provide a two-dimensional optical switch in which the deflection means are less bulky, while minimizing optical losses and adopting a strip of space frequencies of reasonable extent.
- the invention proposes to resolve this drawback by virtue of an optical beam switch comprising a series of optical input channels and a series of optical output channels, two cells with spatial modulation of optical index capable of respectively deflecting an optical beam. leaving an inlet channel and arriving on a output, characterized in that each series of optical channels is distributed along two dimensions transverse to the direction of the channels and in that the cells with spatial index modulation are each designed to produce deviations according to these two dimensions.
- FIG. 1 is a perspective view of a switcher according to the invention
- FIG. 2a is a longitudinal sectional view of a switch in transmission and normal incidence
- FIG. 2b is a view in longitudinal section of a switcher in transmission and inclined incidence
- FIG. 2c is a view in longitudinal section of a referrer in reflection with an intermediate mirror
- FIG. 3 is a front view of a set of two deflection cells each comprising two parts each intended to deflect respectively the one and the other sub-beam each time from a separation of a beam d entry, these two parts each constituting a series of lines alternately belonging to a first and a second part;
- FIG. 4 is a front view of a set of two deflection cells each comprising two parts each intended to deflect respectively the one and the other sub-beam each time from a separation of a beam d entry, these two parts each constituting non-interlaced surfaces;
- FIG. 5 shows, in a device according to the invention, a frame of reference centered on an optical axis of a macrolens, and the position in this frame of diffraction points of different orders arriving on an output cell, after deflection by diffraction produced by an input cell.
- FIG. 6 is a simplified longitudinal sectional view of a switcher according to the invention, the optical beams of which have been reported in the plane of the figure and the optical elements of which have been added along the path of the beams;
- the interconnection device of FIG. 1 has input / output modules 100 and 200 each consisting of a matrix of optical fibers 110, 210 associated with a matrix of micro-lenses 120, 220 whose function is to collimate on a distance necessary for the operation of the system the beams coming from the optical fibers.
- the inputs and outputs are therefore organized in two-dimensional matrices of collimated beams using microlenses. It further presents spatial light modulating components, here liquid crystal 300 and 400, with which it is possible to create localized index variations, so as to diffract the collimated beams in variable directions.
- spatial light modulating components here liquid crystal 300 and 400, with which it is possible to create localized index variations, so as to diffract the collimated beams in variable directions.
- a first deflection implemented by the device 300 makes it possible to direct the incident beam towards the direction (s) corresponding to the desired output fiber (s).
- the second deflection (cell 400) makes it possible to make the axis of the beam and that of the output fiber parallel.
- This second deflection is essential to ensure effective coupling therein, in particular in the (usual) case where single-mode optical fibers are used.
- These spatial light modulators (or “deflection” cells) 300 and 400 operate in reflection and are located in the same plane. They are divided into “sub-cells” each dedicated to an input or output fiber. Thus, only a silicon substrate is used for the control of the inlet deflectors and of the outlet deflectors, facilitating the positioning and alignment of the system;
- the device of FIG. 1 also has a lens 500 (several in one variant), called here macrolens, as opposed to collimating microlenses, one of whose roles is to prevent the light directly reflected by the spatial light modulators from coming disturb the output channels and ensure that the same spatial frequency band is used on all the sub-cells of the spatial light modulators, which limits the bandwidth (in spatial frequencies) of these components.
- a lens 500 singular in one variant
- macrolens as opposed to collimating microlenses, one of whose roles is to prevent the light directly reflected by the spatial light modulators from coming disturb the output channels and ensure that the same spatial frequency band is used on all the sub-cells of the spatial light modulators, which limits the bandwidth (in spatial frequencies) of these components.
- Such a device makes it possible to limit the spatial frequency band necessary for a given number of inputs / outputs, and also to significantly improve the optical isolation between the unconnected inputs / outputs (reduction in optical crosstalk).
- the judicious positioning of the macrolent lenses makes it possible to minimize, for a given capacity of the system, the spatial frequency band required for the spatial light modulators, and, consequently, to minimize the optical losses of the system and / or improve its compactness.
- the distance between the point of convergence and the cell furthest from this point of convergence corresponds to the diagonal of one half of the opposite cell.
- This diagonal is shorter than the diagonal of the total cell, so that the maximum deviation to be applied to a beam is smaller than in a device where the point of convergence would have been placed at a corner of this opposite cell.
- the maximum deviation to be applied being low, the deflection means require only a reasonable power, and are therefore less bulky, which makes it possible to improve the compactness of the assembly.
- the present switch has an intermediate optic, here a mirror 600, making it possible to direct the beam, after deflection by the first spatial light modulator 300, towards the second spatial modulator 200.
- Additional optics are inserted between the micro- and macro-lens arrays to separate the two polarization components transported by the optical fibers, especially in the case where standard single-mode fibers and modulators are used spatial light whose characteristics depend on the polarization (mounting with diversity of polarization).
- the choice of the position of the axes of the macro-lens (s) 500 and the spatial organization of the spatial light modulators, in particular in the case of a mounting with diversity of polarization, is presented in detail below.
- Spatial light modulators operating in reflection are used: this approach makes it possible to use high resolution components produced on a non-transparent substrate (firstly space modulators of liquid crystal light addressed by VLSI, or other technologies to base of electro-optical phase modulators transferred to VLSI).
- the deflection cells and the macrolentines are tilted so as to angularly separate the beams from the normal of the deflection cells.
- FIGS. 2a to 2c illustrate the transition from a mounting in transmission and normal incidence (Figure 2a) to a mounting in transmission and inclined incidence ( Figure 2b), then to a mounting in reflection with an intermediate mirror (Figure 2c).
- the beams incident on the cells in reflection pass twice through the macrolent 500, and the assemblies in transmission (that is to say without reflection) are therefore represented with a macrolent of each side of the deflection cells.
- This architecture is relatively compact. It also allows, before even placing the macrolenses, a global alignment of the system using the beams reflected directly by the cells (orders 0).
- the inlet deflection cell 300 it is useful for the inlet deflection cell 300 to be in the same plane as the outlet cell 400: this simplifies the final assembly of the system, and makes it possible to benefit from high relative positioning precision of the this deflection line (in particular when the modulator is produced from a VLSI circuit).
- the device does not have any moving part.
- the beam from a microlens 500 is separated into its two polarization components using a calcite plate (or a polarization splitter cube according to a variant ), then the polarization component orthogonal to the direction of friction of the liquid crystal is rotated by 90 ° using a half-wave plate.
- a calcite plate or a polarization splitter cube according to a variant
- the polarization component orthogonal to the direction of friction of the liquid crystal is rotated by 90 ° using a half-wave plate.
- two birefringent crystal blades associated with half-wave plates (or a liquid crystal cell) and placed respectively at the input and at the output of the system make it possible to make it insensitive to light polarization, even if spatial light modulators are sensitive to light polarization (local polarization diversity).
- each of these two components constitutes a sub-beam which is then treated individually and independently, that is to say that each deflection cell has distinct zones which each deflect a respective polarization of the same beam (polarizations momentarily brought back parallel to each other after separation).
- the reverse process (half-wave plate + calcite or cube) makes it possible to redifferentiate the orientations and to recombine the two polarization components. Note that the lengths of the optical paths followed by these two polarization components must be very close (0.3 mm, for a polarization mode dispersion (PMD) of 1 ps). This mounting with diversity of polarization doubles in practice the necessary capacity. Two options are now considered, with reference to Figures 3 and 4.
- the deflection cells 300 include rectangular active zones, comprising an interlacing of the lines of sub-cells, by calling a sub-cell a part of a cell which deflects a single beam.
- a line of sub-cells alternately belongs to the part intended to deflect the redirected sub-beams, and alternately to the part intended to deflect the other sub-beams, not redirected here.
- the input deflection cell 300 is composed of 2M rows of M sub-cells (2M ⁇ M).
- the even lines are used for the deflection of the sub-beams from the horizontal polarization components and the odd lines for the deflection of the sub-beams from the vertical components (other arrangements are also possible).
- the polarization separator element is preferably a calcite plate placed against the microlens array 120. Its thickness must allow a shift between polarization components corresponding to the center-to-center spacing of the sub-cells of two consecutive lines .
- the polarization rotation is then carried out by N half-wave plates situated opposite the even lines of sub-cells. These strips can be glued to the calcite blade. This function can also be ensured by a liquid crystal cell in transmission of the twisted nematic type whose pixels are bands located opposite the even lines. Note that this assembly requires matrices of fibers and microlenses of rectangular shape, where the vertical step is double the horizontal step, itself equal to the step of the sub-cells.
- the two separate sub-beams, coming from the two polarization components, are treated separately by two deflection parts forming different surfaces in each cell 300 and 400.
- these parts are of square active area (MxM sub-cells), that is to say a total of four square deflection parts for the whole of the two cells 300 and 400 grouped together (2 for the entry, 2 for output).
- the matrices of fibers 110, 210, and of microlenses 120, 220 are regular square matrices, the pitch of which is substantially equal to that of the sub-cells.
- the polarization separator element is preferably a separator cube, placed against the matrix of microlenses 120, 220, and a half-wave plate is placed against one of the exit faces of the cube.
- two assemblies each consisting of a polarization splitter cube, a half-wave plate, and another splitter cube, are placed respectively at the input and at the output of the system, and allow, associated with four active deflection zones, to make the system insensitive to light polarization, even if the spatial light modulators are sensitive to polarization (global polarization diversity)
- the active deflection zones are located on a VLSI.
- a single VLSI circuit therefore includes the active deflection zones and makes it possible to control them simultaneously.
- the hatched zones correspond for example to the sub-cells which process the polarization component horizontal, while the white areas are reserved for the other polarization component.
- FIGS. 3 and 4 indicate the positions of the axes of macrolentils, referenced X1 and X2 in FIG. 3 and X1, X2, X3, X4, in FIG. 4.
- each macrolens being associated with an active deflection zone, and making it possible to increase the capacity, to reduce the optical losses, and / or to improve the compactness of the system. Note that in the case of a global polarization diversity (figure
- the lens axes and their focal points will be placed outside of the opposite cells, of the active zones, that is to say outside of the beam path zone located between the two cells 300 and 400, so that the order 0 and negative orders do not arrive on the cells, and also are not troublesome for any of the active deflection zones.
- the lens axis will be placed (FIG. 5) so that the positions of the centers of sub-cells are given, in the frame of reference of the lens, by: i positive, or zero integer with j positive, negative, or zero integer, corresponding to a sub-cell (i, j) where h is the center-to-center spacing of the sub-cells (equal to that of the fibers, except for parallax effects).
- the other potentially troublesome positive orders can be more intense than order 5, but will be fed back through the output fibers, therefore more attenuated than order 5.
- the gain in optical isolation for the complete system is estimated at more than 20 dB.
- the pitch of the diffraction grating is inversely proportional to the length of the vector connecting the projection of the origin O of the axis of the macro-lens in the exit plane at the center of the area to be reached (area of cell 400 corresponding to the desired exit channel).
- the pitch of the diffraction grating is chosen so that order 1 has its center in coincidence with the center of the area (solid circles in the figure).
- the position of the higher orders (of order M> 1) is also represented: these are in the extension of the vector connecting O to the center of the zone to be reached, the distance from their center to O being equal to M times the distance from O to the center of order 1.
- the hatched circle corresponds to the case where a higher order (here the order
- this center must be close to the middle of one of the sides of the square (or of the rectangle in the case of local polarization diversity) consisting of the all of the exit zones, so that the minimum network pitch is not too low (which would be the case if there was a significant angular deviation, due to the placement of the center of the lens in a remote zone of the device ). It is also preferable that the center of the lens be distant from the center of the nearest deflection zone, by a distance at least equal to the width h of a zone, so as to limit the disturbance brought about by the orders 0 networks.
- O is offset along y by a zone half height relative to the center of the nearest sub-cell, and the following offset x corresponds to% of an area width relative to this time next to the nearest area (i.e. 1.25 times from the center of the nearest area).
- the transmission of unwanted orders is avoided by placing the macro-lens so that its optical axis is at a distance from the center of the closest area, measured parallel to one or the another of the directions x or y, which is not a multiple of the distance between two successive zones, also measured in this same direction x or y.
- This arrangement is even more advantageous when it is verified both with respect to the x axis and with respect to the y axis.
- the interconnection system will comprise two or four deflection parts, each treating 2M ⁇ M or MxM beams: two cells of square active zones (components insensitive to polarization); two rectangular active area cells (local polarization diversity); four cells of square active zones (global polarization diversity).
- VLSI circuit integrated circuit on highly integrated silicon
- this circuit it is also advantageous for this circuit to include a maximum of active areas, taking into account technological limitations (size of the photomask reticle, surface of an active area and its peripheral electronics, number and not of the contact pads, size of the adhesive joint necessary for sealing the liquid crystal cell, etc.).
- the losses of optical power associated with the deflection of each optical beam depend on the value of the deflection angle.
- FIG. 6 shows the effect of macrolentils on the geometric distribution of the beams.
- the lens 500 of FIG. 1 has been split to illustrate the fact that, in FIG. 1 , the lens 500 is crossed twice by each beam.
- the deflection angle at the input does not depend, thanks to the presence of a converging macro-lens in front of the input cell 300 ( or any other type of convergent mounting, such as a series of lenses on the same optical path for example), as the output (not the input considered).
- all the orders 0 of light being, whatever the input considered, focused on the axis of the input macrolens, it is necessary, whatever the input considered, the same deflection so that the order 1 is deflected on a given output.
- the deflection angle at the outlet does not depend, thanks to the presence of a converging macrolensis in front of the outlet cell 400 (or any other type of mounting converging substantially on the input cell, such as a series of lenses on the same optical path for example), as the input (not the output considered). It is therefore possible to correct the output deflection losses by an attenuator with a fixed attenuation distribution in front of the input cell 300, referenced 350 in FIG. 6.
- Attenuators are, according to a variant, non-programmable attenuators, of even lower cost.
- the present device uses adjustable attenuators on the inputs and outputs, the presetting of the attenuators making it possible to obtain uniform optical losses on all the possible connections between the inputs and outputs of the system, and independent of the configuration of these connections.
- the attenuators are therefore of fixed attenuation.
- the input attenuators [resp. output values] must be preset to loss values of type Cste -p e (i) - p 2 (i) [resp. Cste '- p x (j ' ) -p s (j)].
- the optical centers of these lenses are advantageously placed on opposite sides of the light path, so that the effects of lenses compensate each other and that the deviations to be implemented by the deflecting cells are not too high.
- the liquid crystal cell is integrated on a VLSI addressing circuit, that is to say that its essential elements are affixed successively and irreversibly on this circuit, these steps corresponding to integration.
- the following table summarizes the main parameters characterizing the geometry chosen for the system. It presents two variants: the first (left column) combines two active zones within the same photomasking reticle; in the second (right column), each active zone occupies a crosshair.
- This table also gives the dimensions of the active zones, which are slightly smaller than the fiber matrices (parallax), and their relative location (edge to edge gap along x and y).
- the dimensions of the reticle are calculated taking into account the margins necessary for the glue joints and contact pads. The surface occupied by the adhesive joints is significant compared to the useful surface of the circuit.
Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR0007757A FR2810416B1 (fr) | 2000-06-16 | 2000-06-16 | Aiguilleur optique de grande capacite a base de modulateurs spatiaux de lumiere |
FR0007757 | 2000-06-16 | ||
PCT/FR2001/001875 WO2001096939A1 (fr) | 2000-06-16 | 2001-06-15 | Aiguilleur optique a base de modulateurs spatiaux de lumiere |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1290489A1 true EP1290489A1 (fr) | 2003-03-12 |
Family
ID=8851378
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP01945455A Withdrawn EP1290489A1 (fr) | 2000-06-16 | 2001-06-15 | Aiguilleur optique a base de modulateurs spatiaux de lumiere |
Country Status (6)
Country | Link |
---|---|
US (1) | US6714339B2 (fr) |
EP (1) | EP1290489A1 (fr) |
CN (1) | CN1206568C (fr) |
AU (1) | AU2001267675A1 (fr) |
FR (1) | FR2810416B1 (fr) |
WO (1) | WO2001096939A1 (fr) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB9923428D0 (en) * | 1999-10-04 | 1999-12-08 | Thomas Swan & Company Limited | Optical switch |
US7486443B1 (en) * | 2000-06-05 | 2009-02-03 | Avanex Corporation | High extinction ratio and low crosstalk compact optical switches |
US7057787B2 (en) * | 2004-10-29 | 2006-06-06 | Northrop Grumman Corporation | Architecture for large-FOR EO-crystal-based agile beam steering |
JP4695424B2 (ja) * | 2005-03-31 | 2011-06-08 | 富士通株式会社 | 光スイッチ装置およびその制御情報更新方法 |
FR2939516B1 (fr) * | 2008-12-05 | 2011-01-21 | Thales Sa | Telemetre |
CN102169271B (zh) * | 2011-03-28 | 2012-09-19 | 上海交通大学 | 基于液晶偏振调制的光频谱幅度编码解码器 |
US9106663B2 (en) | 2012-02-01 | 2015-08-11 | Comcast Cable Communications, Llc | Latency-based routing and load balancing in a network |
CN104410449B (zh) * | 2014-10-16 | 2017-10-24 | 北京理工大学 | 用于无线光通信的多路光谱信号通道选择接收系统 |
US20170255078A1 (en) * | 2016-03-03 | 2017-09-07 | Huawei Technologies Co., Ltd. | Wavelength selective switch with monitoring ports |
WO2023026946A1 (fr) * | 2021-08-23 | 2023-03-02 | 株式会社フジクラ | Dispositif d'opération optique, procédé de fonctionnement optique et procédé de fabrication pour dispositif d'opération optique |
CN114660717B (zh) * | 2022-04-01 | 2022-11-08 | 长沙思木锐信息技术有限公司 | 片上空间光调制器、散射聚焦系统及光调制方法 |
GB2618397A (en) * | 2022-04-29 | 2023-11-08 | Huber Suhner Polatis Ltd | Optical switch |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4948229A (en) * | 1988-03-18 | 1990-08-14 | The United States Of America As Represented By The Secretary Of The Air Force | Optical switches using ferroelectric liquid crystals |
JPH0627501A (ja) * | 1992-07-13 | 1994-02-04 | Oki Electric Ind Co Ltd | 光スイッチ |
US5477350A (en) * | 1993-06-01 | 1995-12-19 | General Electric Company | Interferometric spatial switch for polarized or unpolarized light using liquid crystal |
DE69515889T2 (de) * | 1994-09-30 | 2000-12-07 | Univ Cambridge Tech | Optischer schalter |
US6049404A (en) * | 1997-04-02 | 2000-04-11 | Macro-Vision Communications Inc. | N+M digitally programmable optical routing switch |
US6430328B1 (en) * | 2000-10-13 | 2002-08-06 | William H. Culver | Optical switch |
-
2000
- 2000-06-16 FR FR0007757A patent/FR2810416B1/fr not_active Expired - Fee Related
-
2001
- 2001-06-15 US US10/311,085 patent/US6714339B2/en not_active Expired - Fee Related
- 2001-06-15 WO PCT/FR2001/001875 patent/WO2001096939A1/fr active Application Filing
- 2001-06-15 CN CNB018127738A patent/CN1206568C/zh not_active Expired - Fee Related
- 2001-06-15 AU AU2001267675A patent/AU2001267675A1/en not_active Abandoned
- 2001-06-15 EP EP01945455A patent/EP1290489A1/fr not_active Withdrawn
Non-Patent Citations (1)
Title |
---|
See references of WO0196939A1 * |
Also Published As
Publication number | Publication date |
---|---|
CN1441922A (zh) | 2003-09-10 |
FR2810416B1 (fr) | 2003-08-15 |
CN1206568C (zh) | 2005-06-15 |
US20030161028A1 (en) | 2003-08-28 |
FR2810416A1 (fr) | 2001-12-21 |
AU2001267675A1 (en) | 2001-12-24 |
US6714339B2 (en) | 2004-03-30 |
WO2001096939A1 (fr) | 2001-12-20 |
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