CN1661950A - GIRES-TOURNOIS interferometer with faraday's rotator used in optical signal staggered multi plexer - Google Patents

Abstract

GTIFR interferometer in use for interleaving multiplexer or de-interleaving multiplexer includes following parts and structures: Gires - Toumois interferometer possessing a 45 degrees Faraday rotator located between reflectors of the interferometer; a 22.5 degrees Faraday rotator located at optical path on Gires - Toumois interferometer and interleaving multiplexer or de-interleaving multiplexer possessing GTIFR. GTIFR interleaving multiplexer of compensating dispersion includes Gires - Toumois interferometer in use for providing dispersion compensation.

Description

Be used for the GIRES-TOURNOIS interferometer that the light signal interleaver has Faraday rotator

Technical field

Present invention relates in general to the light communication system technical field.More particularly, the present invention is with relevant such as the such jockey of the interleaver that is used to connect between the dwdm system part and deinterleave multiplexer.The channel frequency separation of these dwdm system work differs 1/2nd, as is operated in the part of every channel 50GHz and is operated in connection between the part of every channel 100GHz.

This is the U.S. on the 13rd patent application No.09/929 in August calendar year 2001, divides an application for one of 875, and this patent application has been granted authorizes, and its content is combined together with reference to using at this.The application further with the unauthorized patent application No.09/874 that proposes June 4 calendar year 2001,925 is relevant, the content of this patent application is also combined together with reference to using at this.

Background technology

Along with DWDM optical communication development of technology, the frequency interval of channel changes to 100GHz so that 50GHz from every channel 200GHz in the time in several years.When a communication system was upgraded to every channel 50GHz from every channel 100GHz when, it was favourable keeping some old equipment in system, and for example those are designed to the old equipment of every channel 100GHz.By using interleaver and deinterleave multiplexer to connect between old equipment and new equipment, some old equipment can be retained in the system that has been upgraded.

The light signal that interleaver will contain even channel engages with the light signal that contains odd channel.For example, the interleaver of a 50GHz contains a light signal that contains one group of even channel with 100GHz frequency interval one group of light signal with strange channel of 100GHz frequency interval and engages and produce one and contain this and organize even channel and this organizes the emergent light signal of the every channel 50GHz of having of strange channel frequency interval with one.

A deinterleave multiplexer turns the processing of interleaver around.For example, the deinterleave multiplexer of a 50GHz produces two outgoing signals with even channel and strange channel separation, an outgoing signal comprises one group of even channel with 100GHz channel frequency separation, and an outgoing signal comprises strange channel and has the 100GHz channel frequency separation.

The basic principle of interleaver is based on the interference of two-beam.Interfere and to have produced the outgoing that a periodicity of passing the multi-wavelength with various combination of this equipment repeats.The channel frequency separation of desirable interleaver is set by control interference fringe pattern.Current manufacturer uses fused optic fiber Mach-Zehnder (Mach-Zehnder) interferometer, liquid crystal, and birefringece crystal, Gires-Tournois interferometer (GTI) and other devices are set up interleaver and deinterleave multiplexer.

Wherein, comparatively speaking interleaver and deinterleave multiplexer based on GTI have many advantages, for example, have very low insertion loss based on the interleaver of GTI, in a wide wave-length coverage, have uniform response (flat-top spectrum), and have minimum polarization-dependent effects.

For the system of 10G bps and 40G of future generation bps, chromatic dispersion must be considered.For the system of higher bit rate, the requirement of chromatic dispersion is strict.Many technology are actual to be used in the interleaver product although have now, and when definite any technology was successful, dispersion characteristics may will be a crucial factors.For success, interleaver not only must have a lower dispersion values in the centre wavelength of ITU, and, in all useful free transmission range of device, lower dispersion values (that is, chromatic dispersion should not reduce available passband) is arranged.Unfortunately, have very large chromatic dispersion based on the interleaver of GTI, for the interleaver of 50GHz up to 70-200ps/nm, for the interleaver of 25GHz, up to 250-800ps/nm.

U.S. Pat 6,169,604 are entitled as " with the nonlinear interferometer that is used for the optical fiber dense wavelength division multiplex device of a phase bias element separated light signal wavelength ", this patent is authorized Cao, therefrom disclose a kind of multiplexer, it includes two nonlinear interferometers, and wherein (US 6 for the GTI that has inner λ/4 wave plates and outside λ/8 wave plates for each nonlinear interferometer (NLI), Fig. 8 of 169,604 and Fig. 9).

At relevant pending application application No.09/874,925 (being entitled as " light signal interleaver and deinterleave multiplexer apparatus with dispersion compensation ") also merged reference together at this, the invention discloses a kind of dispersion compensation interleaver and a kind of dispersion compensation deinterleave multiplexer, they all include a NLI and a GTI dispersion compensator.

In a kind of NLI, it is accurate and difficulty that the angle of the relative polarization direction of c-axle of wave plate is harmonized.To the C-axle of λ/4 wave plates and the λ/8 wave plates theta alignment in the right direction with respect to the light beam polarization of injecting wave plate all is 45 degree.The little angular error of 1 degree that is to say that wave plate rotates in the error of 1 degree, spend to 46 degree or to 44 degree from 45 around the direction of light beam, causes the serious distortion of the group delay of spectral shape and interleaver (or deinterleave multiplexer).Some are because the angular error of λ/8 wave plates causes that the example of distortion will be narrated following.

Angular error has reduced the isolation of interchannel.For example the error of about 1 degree of λ/8 wave plates can make the isolation of even channel and adjacent strange interchannel reduce about 10%.

Angular error makes group delay distortion.Fig. 1 shows the group delay of an interleaver of harmonizing fully based on 50/100GHz NLI (or deinterleave multiplexer).Fig. 1 not only is applied to even channel but also be applied to strange channel.The device based on NLI identical with Fig. 1 used in group delay strange, even channel that Fig. 2 and Fig. 3 show respectively, but λ/8 wave plate C-axles have 1 angular error of spending to 46 degree from 45 of spending.Compared to Figure 1 the distortion of the group delay in Fig. 2 and Fig. 3 is fairly obvious.It should be noted that the distortion that strange channel group postpones is to be different from the distortion of even channel group delay.The asymmetric distortion of so serious group delay makes dispersion compensation very difficult.

Summary of the invention

An object of the present invention is to provide a kind of interferometer that is used for interleaver (or deinterleave multiplexer), a kind of interferometer that strange channel is separated with even channel signal and make up and a kind of group delay feature be not because of the interferometer of phase-shifting element with respect to the caused distortion of angular error of the polarisation of light direction of injecting interferometer.

An object of the present invention is to provide a kind of optics interleaver and deinterleave multiplexer, group delay wherein is difficult for producing distortion because of the angular error of the optical phase shift element that rotates around the axle that beam direction limited.

The further purpose of the present invention provides a kind of interleaver and deinterleave multiplexer, and wherein, the angular error of the optical phase shift element that the isolation of interchannel can not rotated owing to the axle that direction limited around light beam causes degradation.

The further purpose of the present invention provides a kind of interleaver and deinterleave multiplexer, and wherein, GTI is used as a dispersion compensator, and owing to does not have angular error to make that the dispersion compensation effect is more effective.

Objects and advantages of the present invention are provided by a kind of interferometer, and this interferometer is the combination (being called GTIFR between following) of Gires-Tournois interferometer and Faraday rotator.Described GTIFR uses in interleaver or deinterleave multiplexer.

According to GTIFR of the present invention is a Gires-Tournois interferometer with 45 degree Faraday rotators, the Gires-Tournois interferometer of described 45 degree Faraday rotators is between the speculum of Gires-Tournois interferometer, rotate the commentaries on classics device with one 22.5 degree faraday, described 22.5 degree Faraday rotators are positioned on the light path that light entered and left the Gires-Tournois interferometer.Although can use the Faraday rotator of any other kind, described Faraday rotator is preferably garnet.

The structure of described GTIFR comprises a Gires-Tournois interferometer, and described Gires-Tournois interferometer has a partially reflecting mirror on optical coupled to a high reflection mirror.Described speculum be parallel to each other and keep one fixing apart from d.There is one to be positioned at the degree of 45 on light path Faraday rotator in the cavity between described speculum.Described partially reflecting mirror provides the opening that allows light enter and leave described Gires-Tournois interferometer.In described Gires-Tournois interferometer outside, the Faraday rotator of one 22.5 degree is arranged on the light path that enters and leave described Gires-Tournois interferometer.

In the work of GTIFR, as be used in according to single the GTIFR interleaver or deinterleave multiplexer of the present invention, comprise the Faraday rotator that linearly polarized light strange, even channel signal passes 22.5 degree, and become circularly polarized light with 22.5 degree phase differences.The light that is reflected from the Gires-Tournois interferometer produces phase change because GTI and 45 spends the effect of Faraday rotators then.Light passes 22.5 degree Faraday rotators for the second time then, and this changes its phase characteristic again.

Only require a GTIFR according to interleaver of the present invention.Equally, also only require a GTIFR according to deinterleave multiplexer of the present invention.

According to GTIFR of the present invention, when it was used on the deinterleave multiplexer of the present invention, its receiving optical signals, these light signals were the plane polarization light signals on the direction, and included one group of idol channel and one group of strange channel.This signal is reflected by GTIFR, enters a polarising beam splitter then.The signal that includes one group of channel is reflected from polarising beam splitter, and polarising beam splitter is passed in the signal transmission that includes other one group of channel.

According to GTIFR of the present invention, be used to one according on the interleaver of the present invention the time, receive plane polarization light signal with one group of strange channel and one group of idol channel, the polarization direction of even channel is perpendicular to the polarization direction of strange channel.This signal is reflected from GTIFR, and enters a polarising beam splitter, and beam splitter is passed in two groups of channel transmissions there.

As with the related and uncommitted patent application 09/874,925 simultaneously of the application's case in disclosed such, the Gires-Tournois interferometer can be used to in the deinterleave multiplexer or the chromatic dispersion in the interleaver compensate.

According to dispersion compensation deinterleave multiplexer of the present invention, even channel and strange channel signal pass a Gires-Tournois interferometer dispersion compensator before by described GTIFR reflection.

According to dispersion compensation interleaver of the present invention, even channel and strange channel signal pass a Gires-Tournois interferometer dispersion compensator after by described GTIFR reflection.

Description of drawings

Fig. 1 is the curve chart of the group delay of NLI, and wherein the wave plate of the wave plate of λ/4 and λ/8 is basic adjustment.

Fig. 2 shows the curve chart of the group delay of the strange channel of NLI, about 1 degree of the angular error of the wave plate of λ wherein/8.

Fig. 3 shows the curve chart of the group delay of NLI idol channel, about 1 degree of the angular error of the wave plate of λ wherein/8.

Fig. 4 is a block diagram of describing deinterleave multiplexer function.

Fig. 5 shows the light path based on the deinterleave multiplexer of Mach-Zehnder interferometer.

Fig. 6 shows the light path based on the deinterleave multiplexer of polarization-spectral interference instrument.

Fig. 7 a shows the performance diagram of the phase difference φ (λ) of a desirable deinterleave multiplexer as λHan Shuo.

Fig. 7 b shows from the performance diagram of the strange channel outgoing of a desirable deinterleave multiplexer.

Fig. 7 c shows from the performance diagram of the even channel outgoing of a desirable deinterleave multiplexer.

Fig. 8 is the schematic diagram of θ-Du Faraday rotator function.

Fig. 9 has shown the cross section of a Gires-Tournois interferometer.

Figure 10 is the phase response characteristic curve chart of a width of cloth GTI.

Figure 11 is the cross-sectional view according to GTIFR of the present invention.

Figure 12 is the phase delay ψ of the right-hand circularly polarized light ripple of GTIFR _R(λ) and the phase delay ψ of left light wave _LPerformance diagram (λ).

Figure 13 is the curve chart of the phase difference φ (λ) between GTIFR right-hand circularly polarized light ripple and the left light wave.

Figure 14 is based on the performance diagram of strange, even channel outgoing signal of the deinterleave multiplexer of GTIFR.

Figure 15 is the schematic diagram according to the deinterleave multiplexer based on GTIFR of the present invention.

Figure 15 A is the schematic diagram according to the interleaver based on GTIFR of the present invention.

Figure 16 is the schematic diagram according to the deinterleave multiplexer with dispersion compensator based on GTIFR of the present invention.

Figure 17 is the schematic diagram according to the interleaver with dispersion compensator based on GTIFR of the present invention.

Figure 18 is the performance diagram of the group delay τ (λ) of GTI dispersion compensator.

Figure 19 is the performance diagram according to the group delay of the interleaver of the 50GHz that the present invention is based on GTIFR.

Figure 20 is the dispersion characteristic curve figure according to the interleaver of the 50GHz that the present invention is based on GTIFR.

Figure 21 is the group delay frequency characteristic curve chart according to the interleaver of the 50GHz with GTI chromatic dispersion benefit device that the present invention is based on GTIFR.

Figure 22 is based on the dispersion characteristic curve figure that the 50GHz interleaver of device is mended in the GTI chromatic dispersion that has of GTIFR.

Embodiment

Fig. 4 shows a light deinterleave multiplexer and incident that is associated and outgoing signal.In Fig. 4, deinterleave multiplexer 10 receives and contains one group of idol channel and one group of strange channel, λ ₁, λ ₂, λ ₃, or the like incident optical signal 12, and provide one to contain λ ₁, λ ₃, or the like the emergent light signal 14 of strange channel, also provide and contain even channel lambda ₂, λ ₄, or the like the emergent light signal 16 of a separation.

Fig. 5 shows the functional-block diagram based on the deinterleave multiplexer 20 of Mach-Zehnder interferometer.A branch of incident beam 22 enters beam splitter 24.Beam splitter 24 outgoing two light beams 26 and 28.The power of light beam 26 is approximately equal to the power of light beam 28.Light beam 26 and 28 enters phase-shifter 30, and forms light beam 32 and 34, has a phase difference between them.Two light beams 32 and 34 makes up in interferometer 36 and interferes.Two kinds of outgoing signals are obtained from interferometer 36, and outgoing signal 38 comprises odd channel, and outgoing signal 40 includes even channel.

Do not use beam splitter in the present invention, a plane polarization light wave is broken down into two perpendicular polarized lightwaves, has the phase difference that is caused by interferometer between two light waves.This phase difference depends on the wavelength of light signal, and is the periodic function of wavelength, has the cycle that equals one or two channel spacing.The outgoing signal of strange channel is interfered and formed to the mutual perpendicular polarized lightwave component that passes polarising beam splitter (PBS).The outgoing signal of even channel is interfered and formed to the component that is reflected from PBS.

In derivation subsequently, some are arranged for making according to interleaver and the necessary parameter derived value of deinterleave multiplexer based on GTIFR of the present invention, comprise the rotation angle value of the reflectivity and the Faraday rotator of GTI partially reflecting mirror.

Fig. 6 shows a width of cloth figure of a deinterleave multiplexer 42.

It is polarization state with the positive z direction wave travels of unit power and edge.

Be parallel to positive y-direction.Polarization Can be expressed as

$\stackrel{\→}{E}=\underset{i=1}{\overset{2}{\mathrm{\Σ}}}{a}_i{\stackrel{\→}{e}}_i.---\left(1\right)$

Basis vector set

Be perpendicular, just,

$e_i{e}_j^{*}={\mathrm{\&delta;}}_{\mathrm{ij}}=\&lang;\begin{array}{cc}1,& i=\mathrm{<figure-callout\; id="0"\; label="j"\; filenames="A20041000756600231.png,A20041000756600271.png"\; state="\{\{state\}\}">j</figure-callout>}\\ 0,& i\&NotEqual;j\end{array}|.$

Use Jones (Jones) vector, Can be expressed as

$\stackrel{\&RightArrow;}{E}=\left(\begin{array}{c}0\\ 1\end{array}\right)=a_1\left(\begin{array}{c}{e}_{11}\\ e_{12}\end{array}\right)+a_2\left(\begin{array}{c}{e}_{21}\\ {\mathrm{<figure-callout\; id="22"\; label="e"\; filenames="A20041000756600251.png"\; state="\{\{state\}\}">e</figure-callout>}}_{22}\end{array}\right).---\left(3\right)$

Pass an interferometer 44 at light beam, or after interferometer 44 is reflected, light beam e ₁And e ₂Has phase shift φ respectively ₁And φ ₂And equation (3) becomes:

$a_1\left(\begin{array}{c}{e}_{11}\\ e_{12}\end{array}\right)e^{i{\mathrm{\&phi;}}_1}+a_2\left(\begin{array}{c}{e}_{21}\\ e_{22}\end{array}\right)e^{i{\mathrm{\&phi;}}_2}.---\left(4\right)$

In derivation subsequently, the situation that is confined to symmetry is discussed, at this, α ₁=α ₂=α.When light beam advances to polarising beam splitter (PBS) 46, p-ripple (polarization parallel in the y-direction especially as in incident beam) is by (PBS) 46, and s-ripple (having the polarization that is parallel to the x-direction, just vertical with the polarization direction of incident beam) is reflected by the tapered plane of PBS46.The P-ripple 48 that has strange channel is in the outgoing of an exit portal of deinterleave multiplexer 42.And have another exit portal outgoing of the s-ripple 50 of even channel at deinterleave multiplexer 42.

The p-ripple can be represented with following formula:

$a{e}^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\left(e_{12}{e}^{i\frac{\mathrm{\&Delta;\&phi;}}{2}}{e}^{-i\frac{\mathrm{\&Delta;\&phi;}}{2}}\right)\left(\begin{array}{c}0\\ 1\end{array}\right)---\left(5\right)$

And the s-ripple can be represented with following formula:

$a{e}^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\left(e_{11}{e}^{i\frac{\mathrm{\&Delta;\&phi;}}{2}}{e}_{21}{e}^{-i\frac{\mathrm{\&Delta;\&phi;}}{2}}\right)\left(\begin{array}{c}1\\ 0\end{array}\right)---\left(6\right)$

At this, Δ φ=φ ₁-φ ₂

Based on circular polarization, at this

$a=\frac{1}{\sqrt{2}},$

$e_{11}=-e_{21}=-\frac{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}}{\sqrt{2}},$

$e_{12}={\mathrm{<figure-callout\; id="22"\; label="e"\; filenames="A20041000756600251.png"\; state="\{\{state\}\}">e</figure-callout>}}_{22}=\frac{1}{\sqrt{2}},$

The p-ripple is represented with following formula:

$e^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\cos \frac{\mathrm{\&Delta;\&phi;}}{2}---\left(7\right)$

And the s-ripple is represented with following formula:

$e^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\sin \frac{\mathrm{\&Delta;\&phi;}}{2}---\left(8\right)$

Based on plane polarization, at this

$a=\frac{1}{\sqrt{2}},$

$e_{11}=e_{12}={\mathrm{<figure-callout\; id="22"\; label="e"\; filenames="A20041000756600251.png"\; state="\{\{state\}\}">e</figure-callout>}}_{22}=\frac{1}{\sqrt{2}},$

$e_{21}=\frac{1}{\sqrt{2}},$

The p-ripple is represented with following formula:

$e^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\cos \frac{\mathrm{\&Delta;\&phi;}}{2}---\left(9\right)$

And the s-ripple is represented with following formula:

$i{e}^{-i\frac{{\mathrm{\&phi;}}_1+{\mathrm{\&phi;}}_2}{2}}\sin \frac{\mathrm{\&Delta;\&phi;}}{2}.---\left(10\right)$

In order to use figure as shown in Figure 6 to make a deinterleave multiplexer (or interleaver), phase difference φ must satisfy following condition: Δ φ must be periodic with the change of wavelength, this cycle equals one or two channel frequency separation, and in half of each cycle, the value of Δ φ should approach zero (or ± 2m π, at this m is integer), and approach π (or ± (2m+1) π) at second half of phase weekly.

Fig. 7 a is the performance diagram that shows under the perfect condition as the phase difference φ (λ) of λHan Shuo.At this, Δ φ (λ) presents the periodicity that the cycle is two channel frequency separations.

Fig. 7 b is the performance diagram that shows under the perfect condition as the strange channel outgoing of function of wavelength.

Fig. 7 c shows under the perfect condition performance diagram as the even channel outgoing of function of wavelength.

Interferometer and phase-shifter are the critical optical elements that produces phase difference φ.For the circular polarization light wave, phase-shifter is a Faraday rotator (FR).The FR of a θ degree rotates about θ degree with its polarization when the plane polarization light wave passes FR, as described in Figure 8.Incident light wave 52 is by the direction plane polarization that is parallel to the y-axle.After Faraday rotator that passes the θ degree or garnet 54, outgoing light wave 56 is with the direction polarization from y-direction rotation θ degree.According to equation (3), the plane polarization light wave in FR can be broken down into right circular component and left component.The light wave of propagating along positive z-direction is provided by following formula:

$\frac{1}{2}\left(\begin{array}{c}-\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(\mathrm{\&omega;t}-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}\mathrm{nz})\right]+\frac{1}{2}\left(\begin{array}{c}\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(\mathrm{\&omega;t}-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}\mathrm{nz})\right]---\left(11\right)$

Suppose right circularly polarized wave have refractive index n+, and the left ripple has refractive index n, leaves the waveform of Faraday rotator so and is just described by following formula:

$\frac{1}{2}\left(\begin{array}{c}-\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(\mathrm{\&omega;t}-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}{n}_{+}d)\right]+\frac{1}{2}\left(\begin{array}{c}\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(\mathrm{\&omega;t}-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}{n}_{-}d)\right].---\left(12\right)$

This can be write as:

$\frac{1}{2}\exp \left\{i\right[\mathrm{\&omega;t}-(n_{+}+n_{-})\frac{\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\left]\right\}---\left(13\right)$

$\left\{\begin{array}{c}\left(\begin{array}{c}-\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(n_{-}-n_{+})\frac{\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\right]+\left(\begin{array}{c}\mathrm{<figure-callout\; id="1"\; label="i"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">i</figure-callout>}\\ 1\end{array}\right)\exp \left[i(n_{+}-n_{-})\frac{\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\right]\end{array}\right\}$

In order to explain the physical significance of equation (13), be simplified as by definite equation:

According to these definition, equation (13) can be write as:

Equation (14) is described a plane polarization light wave, and its polarization direction has angle

$\mathrm{\&theta;}=\frac{\mathrm{\&pi;d}}{\mathrm{\&lambda;}}(n_{-}-n_{+})---\left(15\right)$

The plane polarization light wave of incident has the plane of polarization that rotates through a θ angle.This also mean when light wave by after θ-Du Faraday rotator, right-hand circularly polarized light ripple and left light wave have phase delay (φ-θ) and (φ+θ) respectively.

Fig. 9 shows the schematic diagram of a Gires-Tournois interferometer (GTI) cross section.Gires-Tournois interferometer 60 has first speculum 62 of a partial reflection, and it has reflectivity R ₁And second speculum 64 of a high reflection, it has reflectivity R ₀The reflectivity R of second speculum 64 ₀Near 100%.Partially reflecting mirror 62 is parallel with high reflection mirror 64 and separates.Space between this two speculum is a cavity 66, and the distance between two speculums is d.First speculum 62 provides a single incident/exit portal, and it allows light to be launched into and penetrates cavity 66.Sept 68 is to make with the super-low expansion material.GTI is one of best choice as the interferometer that uses on interleaver, because the response of the amplitude of GTI is smooth (just wavelength is incoherent).The phase response of GTI is to be periodic with λ, and is provided by following formula:

$\mathrm{\&psi;}\left(\mathrm{\&lambda;}\right)=-2{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}\tan \left(\frac{2\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\right)\right],---\left(16\right)$

At this λ is wavelength, R ₁Be the power reflectance of first reflective mirror, d is the length of cavity, and Be the single-pass phase delay of GTI cavity.

Figure 10 is the curve chart of equation (16), and expression is as the phase response ψ (λ) of the GTI of wavelength X function.

Figure 11 is the schematic diagram according to the cross section of GTIFR80 of the present invention.GTIFR80 comprises a GTI 60 with first speculum 62 and second speculum 64.First speculum 62 is partially reflecting mirrors, has reflectivity R ₁Second speculum 64 is high reflection mirrors, and it has about 100% reflectivity R ₀Not only separately but also be parallel to each other, the distance between two speculums was d for second speculum 64 and first speculum 62 in Figure 11.The Faraday rotator 82 that a θ degree is arranged in the cavity 66 between two speculums.The Faraday rotator 84 that a α degree is arranged before the GTI.Have the GTI reflex time of θ degree Faraday rotator internally at right-hand circularly polarized light ripple and left light wave, phase delay is:

Here, in the equation (16) With

The θ degree FR in GTI come to substitute, because can make right-hand circularly polarized light ripple that the cavity that passes GTI propagates and left light wave produce additional phase delay (φ+θ).When right-hand circularly polarized light ripple and left light wave from left to right pass the FR of α-Du, the GTI that has θ degree FR then internally reflects back, and passes α degree FR from right to left, and total phase delay of right-hand circularly polarized light ripple and left light wave is:

Phase difference ΔΦ between right-hand circularly polarized light ripple and the left light wave is:

The effective length of GTI cavity defines with L, makes

Use equation (20) in equation (19), equation (19) becomes:

$\mathrm{\&Delta;\&phi;}\left(\mathrm{\&lambda;}\right)=-2{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}\tan (\frac{2\mathrm{\&pi;L}}{\mathrm{\&lambda;}}-\mathrm{\&theta;})\right]+---\left(21\right)$

$2{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}1}\tan (\frac{2\mathrm{\&pi;L}}{\mathrm{\&lambda;}}+\mathrm{\&theta;})\right]-4\mathrm{\&alpha;}.$

R in equation (21) ₁, θ, α and L value must be such, promptly Δ φ (λ) will satisfy the above-mentioned requirement that sets about Fig. 6 and equation (7) and (8).The effective length L of GTI cavity is determined by the channel frequency separation of interleaver.For the interleaver of 50GHz, L is 1.5mm.θ is the phase-shift value of curve ψ (λ) (equation among Figure 10 (16)).If ψ _R(λ) and ψ _L(λ) differ about pi/2 each other, as shown in Figure 12, ΔΦ is symmetrical for strange channel and even channel.This just requires 2 θ=pi/2 or θ=π/4.

Because cosine and SIN function are periodic function, and the cycle from-π along reaching+π, the Δ φ in equation (7) and (8) can be limited in the scope that-2 π arrive+2 π.Select the central wavelength lambda of two adjacent channels ₁And λ ₂, make $\frac{2\mathrm{\&pi;L}}{{\mathrm{\&lambda;}}_1}=2\mathrm{m\&pi;}$ With $\frac{2\mathrm{\&pi;L}}{{\mathrm{\&lambda;}}_2}=2\mathrm{m\&pi;}+\frac{\mathrm{\&pi;}}{2}$ (is positive integer at this m).Referring to Fig. 7 a, i.e. Δ φ (λ ₁) can for π or-π, and ΔΦ (λ ₂) can be 2 π, 0 or-2 π.With θ=π/4, $\frac{2\mathrm{\&pi;L}}{{\mathrm{\&lambda;}}_1}=2\mathrm{m\&pi;}$ With Δ φ (λ ₁)=π substitution equation (21) draws:

$4{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{R_1}}\right]-4\mathrm{\&alpha;}=\mathrm{\&pi;}---\left(22\right)$

Will $\mathrm{\&theta;}=\mathrm{\&pi;}/4,\frac{2\mathrm{\&pi;L}}{{\mathrm{\&lambda;}}_2}=2\mathrm{m\&pi;}+\frac{\mathrm{\&pi;}}{2}$ With Δ φ (λ ₂)=-2 π substitution equations (21) draw:

$4{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{R_1}}\right]+4\mathrm{\&alpha;}=2\mathrm{\&pi;}---\left(23\right)$

With equation (22) and (23) addition with subtract each other and draw:

${\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{R_1}}\right]=\frac{3}{8}\mathrm{\&pi;}---\left(24\right)$

With 8 α=π (25)

Equation (24) and (25) provide R1=17.2% and α=π/8 (22.5 °).Note that (λ for Δ φ ₁π of)=-and Δ φ (λ ₂)=2 π or 0, the R that is obtained ₁There is not physical significance with the α value.

Above-mentioned derivation has provided for making a deinterleave multiplexer or the required whole parameter values of interleaver, and these values are as follows:

(1) the reflectivity R of first speculum of GTI ₁=17.2%

(2) the reflectivity R of second speculum of GTI ₀=100%

(3) the θ degree FR θ in the GTI cavity=45 °

(4) the α degree FR α before GTI=22.5 °

Figure 13 is the curve chart of equation (21), and it shows as the phase difference φ (λ) of the function of λ, for the GTIFR of Figure 11, uses the parameter value and the L=1.5mm of these derivation.

The phase shift of this interleaver or deinterleave multiplexer is presented in following formula:

${\mathrm{\&psi;}}_1\left(\mathrm{\&lambda;}\right)=-{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{R_1}}\right]\tan (\frac{2\mathrm{\&pi;L}}{\mathrm{\&lambda;}}-\frac{\mathrm{\&pi;}}{4})----\left(26\right)$

${\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}}{1-\sqrt{R_1}}\right]\tan (\frac{2\mathrm{\&pi;L}}{\mathrm{\&lambda;}}+\frac{\mathrm{\&pi;}}{4})$

With the Δ φ in equation (21) substitution equation (7) and (8), can calculate the signal output of unusual channel ${\left(\cos \frac{\mathrm{\&Delta;\&phi;}\left(\mathrm{\&lambda;}\right)}{2}\right)}^2$ Signal output with even channel ${\left(\sin \frac{\mathrm{\&Delta;\&phi;}\left(\mathrm{\&lambda;}\right)}{2}\right)}^2.$ Figure 14 has shown the result of this substitution.Reflectivity R in Figure 14 ₁Be 18.5% rather than more than derive 17.2%.With reflectivity R ₁Become 18.5% from 17.2% and increased the isolation of passband edge of adjacent channel up to 25dB.In Figure 14, the strange channel dotted line 114 of solid line 112 representatives is then represented even channel.

If based on plane polarization, replace based on circular polarization in the above-mentioned discussion, the result will be with the λ/45 ° Faraday rotators of 4 wave plates replacement in GTI, with the 22.5 ° Faraday rotators of wave plate replacement before GTI of λ/8.This of GTI and wave plate is arranged in the U.S. Pat 6,169,604 of exercise question for " using the nonlinear interferometer that is used for the optical fiber dense wavelength multiplexer of phase bias element separated light signal wavelength " and is described.

From equation (4), the derivation of equation (7) to (10) and (26) is by setting α ₁=α ₂=α is limited under the situation of symmetry.This qualification and these equations are automatic straightenings, no matter whether Faraday rotator is aimed at the polarisation of light direction that enters Faraday rotator.Yet, α under the situation of wave plate ₁≠ α ₂, and equation can not corrected when the c-of wave plate axle does not have with polarization directions aligned.Work as α ₁≠ α ₂It is very complicated that Shi Fangcheng becomes, and demonstrate distortion in spectral shape and the group delay based on the interleaver of NLI or deinterleave multiplexer.

Figure 15 is the schematic diagram of deinterleave multiplexer of the present invention.Deinterleave multiplexer 120 comprises the Gires-Tournois interferometer of a band Faraday rotator, GTIFR122.GTIFR122 as shown in figure 11.Incident optical signal 124 is loaded with the light signal that comprises even channel and strange channel.Collimater 126 collimates signal beams.Loss crystal 128 becomes the light beam of a branch of vertical polarization and the light beam 130 of a branch of horizontal polarization with the beam separation of collimater 126.The light beam of vertical polarization passes a half-wave plate 132 and penetrates from this half-wave plate, becomes horizontal polarization light beam 134.Speculum 136 arrives polarising beam splitter (PBS) 138 with two bundle horizontal polarization beam reflection.Two bundle horizontal polarization signals pass PBS138, the half-wave plate 140 of 22.5 degree cuttings (it is with positive 45 degree of polarization rotation of signal), and garnet 142 (it is with negative 45 degree of polarization rotation of signal) and PBS144 are to GTIFR122.The signal that enters GTIFR122 is a horizontal polarization.The signal that is loaded with strange channel and has a horizontal polarization is reflected from GTIFR122, and pass PBS144, pass the garnet 142 of polarization rotation 45 degree that make the horizontal polarization signal then, pass again and make polarization rotate the half-wave plate 140 of 22.5 degree cuttings of another 45 degree, so just make strange channel signal vertical polarization.The strange channel signal of PBS138 reflection vertical polarization.After the reflection, the strange channel signal of part vertical polarization passes the form ejaculation of half-wave plate 146 with horizontal polarization, and enters loss crystal 148 in PBS138.Another part signal that is reflected from PBS138 directly enters loss crystal 148.The loss crystal partly makes up vertical polarization part and horizontal polarization provides a kind of outgoing signal of strange channel that is loaded with to collimater 150.

The signal that is loaded with even channel reflects from the GTIFR122 outgoing and by PBS144.After the PBS144 reflection, even channel signal has vertical polarization.After the PBS144 reflection, the part orthogonal polarized light passes half-wave plate 152 (polarization direction is changed into horizontal polarization there) and enters loss crystal 154, and part directly enters loss crystal 154.Loss crystal 154 arrives collimater 156 with two parts combination so that an outgoing signal that is loaded with even channel to be provided.

If among the GTIFR122 in Figure 15, outside Faraday rotator is replaced by a Faraday rotator with magnetic direction switch, and α becomes-α, and Δ φ (λ) changes about π in this spline equation (21), and ${\left(\cos \frac{\mathrm{\&Delta;\&phi;}\left(\mathrm{\&lambda;}\right)}{2}\right)}^2$ Become ${\left(\sin \frac{\mathrm{\&Delta;\&phi;}\left(\mathrm{\&lambda;}\right)}{2}\right)}^2,$ And vice versa.The position of outgoing signal is changed, and the outgoing signal of strange channel appears in the collimater 156, and the outgoing signal of even channel then appears in the collimater 150.

Figure 15 A is the schematic diagram of interleaver of the present invention.The interleaver 120 of Figure 15 A is the equipment identical with the deinterleave multiplexer of Figure 15.Figure 15 A receives the incoming signal of a strange channel by collimater 126, receives the signal of an even channel by collimater 156, and at the odd-even channel signal of collimater 150 outgoing combination.

Strange channel signal passes collimater 126 and loss crystal 128.Loss crystal 128 resolves into horizontal polarization part 130 and vertical polarization part with strange channel incoming signal, and vertical polarization becomes horizontal polarization part 134 after partly passing half-wave plate 132.The strange channel signal of horizontal polarization is reflected in speculum 136 and passes through PBS138 then, the half-wave plate 140 of 22.5 degree cuttings, and garnet 142 and PBS144 enter GTIFR122.GTIFR122 is with the horizontal polarization signal reflex of strange channel.

Idol channel incoming signal passes collimater 156 and loss crystal 154, separates the signal into vertical polarization part and the horizontal polarization part of direct arrival PBS144, and horizontal polarization partly passes half-wave plate 152 and continues to be vertical polarization and arrives PBS144.Two vertical polarization parts of idol channel signal are entered GTIFR122 by the PBS144 reflection.

Idol channel signal and strange channel signal leave GTIFR122 together and pass PBS144, the polarization of horizontal polarization signal is rotated the garnet 142 of 45 degree, make polarization rotate the half-wave plate 140 of 22.5 degree cuttings of another 45 degree, this just makes that strange channel signal and even channel signal all are vertical polarizations.The vertical polarization signal is reflected by PBS138.The part of signal is passed half-wave plate 146 and is become horizontal polarization, enters loss crystal 148 then.Remaining signal directly arrives loss crystal 148 from PBS138.Loss crystal 148 with vertical polarization signal and horizontal polarization signal combined after, contain outgoing signal odd, even channel by one of collimater 150 outgoing.

Figure 16 is the schematic diagram that has the deinterleave multiplexer of dispersion compensation according to of the present invention.Incoming signal contains odd channel and even channel.Collimater 126 collimation incoming signals 124.Loss crystal 158 resolves into a vertical polarization signal and a horizontal polarization signal with incoming signal.Half-wave plate 160 is the vertical polarization signal with the horizontal polarization conversion of signals, and incoming signal is exactly vertical polarization like this.PBS162 reflexes to quarter-wave plate 164 with the incoming signal of vertical polarization, and it becomes the circular polarization signal with the plane polarization conversion of signals.The circular polarization signal propagates into dispersion compensator 166, and it makes the about ψ of phase change of signal _c(λ).Pass quarter-wave plate 164 once more from the signal of dispersion compensator 166 reflections.It becomes the circular polarization conversion of signals plane polarization signal of horizontal direction polarization now.The horizontal polarization signal passes PBS162, PBS138, and the half-wave plate 140 (it makes polarization be rotated in the forward 45 °) of 22.5 degree cuttings, garnet 142 (it makes the polarization negative direction of signal rotate 45 °) and PBS144 are to GTIFR122.Contain the strange channel signal of horizontal polarization and the even channel signal of vertical polarization from the signal packet of GTIFR122 reflection.

The strange channel signal of horizontal polarization passes PBS144, garnet 142 (it makes 45 ° of horizontal polarization signal rotation), 22.5 the half-wave plate 140 (it makes polarization rotate another 45 °) of degree cutting, and the reflection by PBS138 are as the strange channel signal outgoing of a vertical polarization.Pass half-wave plate 146 from the signal of a part of vertical polarization of PBS138 reflection, and enter loss crystal 148 as the signal of a horizontal polarization.Directly enter the loss crystal from vertical polarization another part signal of PBS138 reflection.The loss crystal is combined into a strange channel outgoing signal that passes collimater 150 with two parts.

Even channel signal from the vertical polarization of GTIFR122 is reflexed to loss crystal 154 by PBS144.The part of signal was become horizontal polarization by half-wave plate 152 before entering loss crystal 154.The loss crystal partly combines the horizontal polarization part with vertical polarization, and the outgoing signal that one of outgoing is loaded with even channel passes collimater 156.

Figure 17 is the schematic diagram according to the interleaver 200 of dispersion compensation of the present invention.If the difference of the deinterleave multiplexer 180 among the interleaver among Figure 17 200 and Figure 16 only be garnet 142 wind perpendicular to the axle Rotate 180 of paper ° like this garnet 142 among Figure 16 make polarisation of light be rotated in the forward about 45 °, then the garnet among Figure 17 142 makes 45 ° of polarization negative direction rotations.The strange channel incoming signal of collimater 150 collimations.Loss crystal 148 changes the signal that signal becomes vertical polarization with half-wave plate 146.PBS138 reflexes to half-wave plate 140 with the vertical polarization incoming signal of strange channel.Strange channel signal passes the polarization that makes signal and rotates about 45 ° half-wave plate 140 and make polarization rotate another garnet of 45 ° 142, makes strange channel signal become horizontal polarization and pass PBS144 to arrive GTIFR122.Strange channel signal is being kept horizontal polarization by the GTIFR122 reflex time, pass PBS144 then, make the horizontal polarization signal rotate about 45 ° garnet 142 in a direction, make the polarization rightabout rotate about 45 ° half-wave plate 140, the horizontal polarization signal passes PBS138 and 162 and arrives quarter-wave plate 164 like this.Quarter-wave plate 164 becomes the circular polarization signal with the plane polarization signal transition.The circular polarization signal propagates into dispersion compensator 166, and dispersion compensator 166 changes the about ψ c of phase place (λ) of signal, provides as equation (28).After by dispersion compensator 166 reflections, signal passes quarter-wave plate 164 once more, and the circular polarization signal becomes the plane polarization signal on the vertical direction there.The vertical polarization signal is reflexed to half-wave plate 160 and loss crystal 158 by PBS162.Half-wave plate 160 becomes horizontal direction with the change of polarized direction of part signal, and the loss crystal partly combines it with remaining vertical polarization, and transmits an outgoing signal that is loaded with strange channel to collimater 126 these common exit portals.

Be loaded with the incoming signal of even channel because the effect of loss crystal 154 and half-wave plate 152 is become a vertical polarization signal, entered GTIFR122 by the PBS144 reflection then.By after the GTIFR reflection, the polarization of signal is a level at signal, and this signal propagates into dispersion compensator, and from there to propagate into common exit portal with the same mode of above-mentioned strange channel signal.This common exit portal, collimater 126 outgoing just have the composite signal of all channels of dispersion compensation.

In the interleaver of the deinterleave multiplexer of Figure 16 and Figure 17, the Faraday rotator of a band external magnetic field can replace garnet 142.The direction that changes external magnetic field is enough to interleaver is changed over the deinterleave multiplexer, otherwise too.

Total phase shift of the dispersion compensation deinterleave multiplexer of Figure 16 and the dispersion compensation interleaver of Figure 17 is given by the following formula:

ψ _T(λ)＝ψ _l(λ)+ψ _C(λ) (27)

At this ψ _lBe that it is provided by equation (26), do not have dispersion compensation, and ψ c (λ) is the phase response of dispersion compensator 166 from the phase place of GTIFR interleaver or deinterleave multiplexer outgoing signal (λ).Dispersion compensator 166 is Gires Tournois interferometers as shown in Figure 9, and its phase response is given by the following formula:

${\mathrm{\&psi;}}_C=-2{\tan }^{-1}\left[\frac{1+\sqrt{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}}{1-\sqrt{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="A20041000756600271.png,A20041000756600311.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}}\tan \left(\frac{2\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\right)\right]---\left(28\right)$

The group delay of dispersion compensator 166 is given by the following formula:

$\mathrm{\&tau;}\left(\mathrm{\&lambda;}\right)=\frac{0.01{\mathrm{\&lambda;}}^2}{6\mathrm{\&pi;}}\frac{d{\mathrm{\&psi;}}_C\left(\mathrm{\&lambda;}\right)}{\mathrm{d\&lambda;}},---\left(29\right)$

The chromatic dispersion D (λ) that with ps/nm is unit is given by the following formula:

$D\left(\mathrm{\&lambda;}\right)={10}^{-3}\frac{\mathrm{d\&tau;}\left(\mathrm{\&lambda;}\right)}{\mathrm{d\&lambda;}}.---\left(30\right)$

Figure 18 is the characteristic curve of group delay τ (λ) of picosecond of wavelength X function of the conduct micron of dispersion compensator 166, and it is provided by equation (29).

Figure 19 and 20 is respectively the characteristic curve of the chromatic dispersion of the group delay of picosecond of the interleaver (or deinterleave multiplexer) as Figure 15 and every nanometer picosecond, and at this, channel frequency separation is 50GHz, reflectivity R ₁=18.5% and L=1.5mm.

From Figure 20 ,+/-0.08nm (+/-chromatic dispersion in 10GHz) the bandwidth is+/-40ps/nm.

Figure 21 and 22 show respectively group delay and chromatic dispersion curve, they are at deinterleave multiplexer among Figure 16 and the interleaver among Figure 17, wherein, channel frequency separation is 50GHz, reflectivity R ₁=18.5%, and L=1.5mm, wherein dispersion compensator is a GTI as shown in Figure 9, its cavity length d=3mm and the reflectivity R of partially reflecting mirror ₂=0.28%.

In the present invention, reflectivity R ₁Value can be in about 17.2% to about 19.0% scope, and 18.5% is optimum value.Equally, in the present invention, reflectivity R ₂Value can be in about 0.28% to about 0.40% scope, and 0.28% is optimum value.Garnet is the preferable kind of 45 degree Faraday rotators and 22.5 degree Faraday rotators, yet any other suitable Faraday rotator can be used in the present invention.

From Figure 22, ± 0.08nm or ± frequency bandwidth of 10GHz in chromatic dispersion be ± 4.7ps/nm.This only be do not have dispersion compensator interleaver chromatic dispersion 12%.

The typical embodiment of the present invention is narrated at this.These only are in order to describe rather than a kind of restriction.The present invention can have many distortion in force, and the technical staff can take a hint in the disclosed content from the specification of present patent application under the present invention.All this distortion are considered to be in the protection range of patent application of the present invention.

Claims (14)

1, a kind of interleaver, it comprises:

A GTIFR interferometer is used to receive the plane polarized incoming signal that includes even channel signal and the plane polarized incoming signal that comprises odd channel signal, also be used to reflect include even channel signal and strange channel signal by the signal of phase shift; With

A polarising beam splitter, be used for receiving phase shift signalling from GTIFR, and produce a plane polarization outgoing signal that comprises odd channel signal and even channel signal, wherein, the polarization direction and the mutual perpendicular quadrature in polarization direction that comprises the plane polarization incoming signal of odd channel signal that include the plane polarization incoming signal of even channel signal; Wherein, the polarization direction of outgoing signal is identical with the polarization direction of one of incoming signal.

2, interleaver as claimed in claim 1, it further comprises

A Gires-Tournois interferometer dispersion compensator, wherein, outgoing signal from polarising beam splitter is reflected from Gires-Tournois interferometer dispersion compensator, produces the outgoing signal that a chromatic dispersion that includes even channel signal and strange channel signal is compensated.

3, interleaver as claimed in claim 2, Gires-Tournois interferometer dispersion compensator wherein includes a partially reflecting mirror, and described partially reflecting mirror has about reflectivity of 0.28% to 0.40%.

4, interleaver as claimed in claim 2, Gires-Tournois interferometer dispersion compensator wherein includes a partially reflecting mirror, and described partially reflecting mirror has about 0.28% reflectivity.

5, interleaver as claimed in claim 1, it further includes the device of eliminating polarization from plane polarization outgoing signal.

6, interleaver as claimed in claim 5, the device from outgoing signal elimination polarization wherein comprises a half-wave plate, it is with changeable direction of polarization 90 degree of the part of plane polarization outgoing signal, a loss crystal is used for the remainder of plane polarization outgoing signal is engaged with the part that is transformed to produce a unpolarized outgoing signal that comprises even channel signal and strange channel signal.

7, a kind of deinterleave multiplexer, it comprises:

A GTIFR interferometer is used to receive the plane polarization incoming signal that includes even channel and strange channel signal, and reflects a phase shift signalling that includes even channel signal and strange channel signal; With

A polarising beam splitter, be used for receiving described phase shift signalling from described GTIFR interferometer, and produce a plane polarization outgoing signal and a plane polarization outgoing signal that separates that comprises odd channel signal that includes even channel signal, wherein, contain the polarization direction of plane polarization outgoing signal of even channel perpendicular to the polarization direction of the plane polarization outgoing signal that contains odd channel.

8, deinterleave multiplexer as claimed in claim 7, it further comprises:

A Gires-Tournois interferometer dispersion compensator, the incoming signal that includes even channel signal and strange channel signal was reflected from Gires-Tournois interferometer dispersion compensator before by described GTIFR reflection.

9, deinterleave multiplexer as claimed in claim 8, Gires-Tournois interferometer dispersion compensator wherein includes a partially reflecting mirror with the reflectivity between about 0.28% to 0.40%.

10, deinterleave multiplexer as claimed in claim 8, wherein Gires-Tournois interferometer dispersion compensator comprises a partially reflecting mirror with about 0.40% reflectivity.

11, deinterleave multiplexer as claimed in claim 7, it further comprises:

From the plane polarization outgoing signal that includes even channel signal, eliminate the device of polarization.

12, deinterleave multiplexer as claimed in claim 11, the remainder that the device of wherein eliminating polarization from the plane polarization outgoing signal that includes even channel includes the half-wave plate of changeable direction of polarization 90 degree of a part of an outgoing signal that will include even channel signal and a plane polarization outgoing signal that will include even channel be transformed the part combination to produce a loss crystal that includes the unpolarized outgoing signal of even channel.

13, deinterleave multiplexer as claimed in claim 7, it further comprises:

From the plane polarization outgoing signal that comprises odd channel signal, eliminate the device of polarization.

14, deinterleave multiplexer as claimed in claim 13, the device of wherein eliminating polarization from the plane polarization outgoing signal that comprises odd channel includes a half-wave plate, be used for comprising changeable direction of polarization 90 degree of outgoing signal of the part of odd channel signal, the remainder of a plane polarization outgoing signal that will comprise odd channel be transformed the part combination to produce a loss crystal that comprises the unpolarized outgoing signal of odd channel.

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