JPS5885402A - Fiber wired type rotary optical switch - Google Patents

Abstract

PURPOSE:To obtain a fiber wired type rotary optical switch where a movable part is small as much as possible and the crosstalk and the insertion loss are small, by using a disc. CONSTITUTION:One optical fiber incoming line 13 and (n-1)-number of fiber outgoing lines 14-i (n is divisor of 360) are arranged in the circumferential part of a fixed cylinder 11 in parallel with the revolbing shaft at intervals of Q0= 360/n. Respective fiber end faces of the incoming line 13 and outgoing lines 14-i are exposed on the same plane as the upper end face of the cylinder 11. (n-1)- number of wiring optical fibes 15-i whose number is equal to that of outgoing lines 14-i are arranged in a rotary cylinder 12 so that respective both end faces of fibers 15-i are exposed on the same circle in a plane facing the incoming line 13 and outgoing lines 14-i on the upper end face of the fixed cylinder, and respective optical fibers are wired in the rotary cylinder 12 so that angles made by both ends of the first-the (n-1)th fibers and the axis of the cylinder 12 are theta0, 2theta0, 3theta0,-(n-1)theta0 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an optical switch with low insertion loss and low crosstalk, especially in the dark between the edge of a plurality of optical fibers and the output line of a plurality of optical fibers. Connect the line′
This invention relates to a fiber-wired rotary access optical suite.

There is a conventional light switch in the form of a yuzu,
An example of this is a directional coupler using a waveguide formed by diffusing Ti on a LiNb0a substrate, and an optical switch is used in a barrel. ``Consideration of Switch'' (Hikari kt Nireken materials, Vo.
l, 0Q1ii 79- /4'6. pp, 7-
/2. /97ri). In this Yuzu optical switch, two waveguides are placed in instantaneous contact.
A4 placed on the top with a buffer layer made of AJhOs interposed therebetween.
'Apply a voltage to the electrode, and add 19 to the electro-optic effect.
By utilizing the fact that the coupling foot of the two waveguides changes, light incident from one waveguide is switched to the same waveguide or the other waveguide and extracted. The crosstalk of this 5-way injection coupler type is -2Ad13°, and the insertion loss is ≠, /; dB.

A second example of a conventional optical switch is a thin film total reflection J12 optical switch that utilizes total reflection of light at the boundary between a high refractive index region and a bending index region in a thin film guided waveguide. ,H,'
l'erul, M., Kobayashi and T.
, by Kasai ” T'otal
reflection optical wave
guide 5w1tch” (Electr
on, Lett,, Vol, A7.11! '1-
1. pp. 77-79°/91/). In this optical switch, thin 1 as a low refractive index region is used.
1j, 3 refractive index 02'ge other high refractive index regions refractive index n
2, and when the town animal body placed above this thin film is separated from the low refractive index region, the light incident on the refractive index region is Be totally reflected. However, β
The values β' are the propagation constant in the high refractive index region and the propagation constant in the low refractive index region when there is no movable dielectric material, respectively.

When the movable M9 body comes into contact with a low refractive index region, the propagation constant β" of the low refractive index region becomes larger than β'. At this time, the condition of the above equation no longer holds, and the light propagates through the low refractive index region. -t m has passed.

In a thin film total reflection type optical switch, the path of the light is switched by bringing the 11 dynamic dielectric into contact with the thin film or separating it from the thin film based on this technique. crosstalk (knee JdB.

Insertion loss is 3 dB.

The crosstalk of an optical switch is required to be less than -6θ dB4), but in the above-mentioned direction +q = coupler type or total internal reflection type optical switch, the crosstalk is -1, OdB due to the incomplete scattering of the optical wave path by 1. It is difficult to obtain less crosstalk.

As a third example of a conventional optical switch, the original switch using a Q-type and liquid crystal switch is a 'Low'
-cross-talk, 2X, 2 optica
l5w1tch” (Opt,, I,ett,.

Vol, A, IIIkkA, pp, 27j-2
77, 15#/) Nioite has been proposed. By applying a voltage to a liquid crystal, it is possible to change the arrangement of molecules, and thereby the direction of polarization of light can be changed. This optical switch uses a liquid crystal and a combination prism that has different reflection or transmission characteristics depending on the polarization direction to switch the entire light. This optical switch has a crosstalk of -27 dB and an insertion loss of 2. It is jdB. In optical switches using liquid crystals, it is difficult to reduce crosstalk to 1-60 dB or less due to scattering by liquid crystal molecules.

In history, both sides intersect between the optical fiber input line and the optical fiber output line arranged without a specified commercial angle (for example, 90°).
An optical switch that performs all switching operations by placing a reflecting prism in a position where the reflecting prism moves in and out of the optical path is manufactured by H, Yamamoto, M, Yo.
koyama, J-1, Ogiwara work M,
Yoahlda VC Eli-Large-5cale
and low −1ossoptieal 5w1
tch matrix for optical aw
ltching aystenis” (Jour, o
f Opt, Commun, Mo1. /, N
&12. pp. 74t-72, /910). With this sophisticated matrix optical switch, the scattering of unnecessary light is very small, so the crosstalk is -AO
dB or less, which satisfies the requirements in terms of crosstalk. In addition, the insertion loss is as small as θJjdB. However, in order to configure the entire switch matrix of /θ It becomes a thing and disappears again
It has the disadvantage that the electric power is also large.

On the other hand, is it possible to use rotating access for the wiring of optical fiber spectroscopy switches? The light switch of the form was British Special Publication W1-No./231rj Otsu/No.
23t't3. British Patent No. 1.23
No. 1,36/ is related to the /Xn optical system, and here, as shown in Fig. 1, a rotating jig 3 is inserted between two double force jigs l and 2, and a fixed W6j with 7 optical fibers in its center! After a few minutes of Q-k, attach multiple (0) optical fiber outputs fftn and t to the circle IN of a predetermined radius on both legs of the jig, and then attach the rotating jig 3.
In this method, the wiring fiber 6 is colored by bending it so that the central part of the rotating jig L faces the optical fiber-containing wire, and the peripheral part of the rotating jig L faces the optical fiber output j. do. Here, by rotating the rotating jig 3, the optical sound wiring fiber 6 from the input line μ is guided to any one of the output lines j. But with this light switch configuration.

In order to access a certain optical fiber leg, the rotation jig 3 must be rotated by a maximum of 360° x (/-//n)If, so the disadvantage is that the access time becomes longer. . In addition, since it is a /Xn optical interconnect, it must be used in multiple stages to construct a complete nXn optical interconnect, and the overall connection loss cannot be ignored.

The optical switch of special public Sho 5A-2,31r≠No.
There are three jigs l arranged in the same way as in FIG.

2. All parts have 3 parts, +7j leg fittings 2 have multiple (for example, 2) C fibers in 7. Optical fiber output wires are placed on the circumference of the foot radius. A plurality of optical fiber wires 9 (for example, g wires) are placed on the rotating jig 3, so that both ends thereof can face the end faces of the optical fiber input line 7 and the optical fiber output line r, respectively. This optical switch is a closed-base type switch, which is installed in the hole 5 located on the circumference of the foot radius. , T1 is a switch that has a negative impact on the terminals connected to each other, and has the disadvantage that when a certain pair of lines are connected, it is not possible to connect the other line of sight arbitrarily. Also, in the case of this optical switch, there is a drawback that the access time is long because the configuration of the wiring fiber is not optimized. Therefore, the purpose of the present invention is to eliminate this drawback of the conventional method by using a circular disk. It is an object of the present invention to provide a fiber-wired rotor V-optical integer that uses sound to make the moving parts as small as possible, and at the same time has low crosstalk and low insertion loss.

Another object of the present invention is to provide a fiber-wired rotary optical integer with reduced access time.

ff18 will be explained in detail below with reference to the drawings.

FIG. 3 shows an example of a lXj optical Swiss inner according to the present invention.

In Figure 3, // is a fixed cylinder, /! is a fixed cylinder //
It is a rotating cylinder that has the same rotation axis as the fixed cylinder // and faces the fixed cylinder with a gap in between. The fixed cylinder // has seven optical fibers /3 and (n
-7) Optical fiber output i/F-i (i=/, 2.・
..., (n-/)) are arranged inside the circumferential portion of the cylinder //, parallel to the axis of rotation, with an interval of θo-360/n. These incoming lines/3 outgoing lines/
Position each fiber end face of 'l-i so that vCu protrudes on the same plane as the upper end face of the fixed cylinder //.

In the example of Fig. 3, n = 6, and the optical fiber output solution /Goo/~/F-, f is set at the same circumference at every 600 angular position with respect to the entry line /3 in the τ work 5 shown in Fig. Inside the rotating cylinder/2, there are (n-/) original fibers for wiring 15-i (1=/2), which are equal to the number of optical fiber output lines/F-1.
,,2. ......, (n-/)) are exposed on the surface opposite to the entry line/3-output line/dar I on the upper end surface of the fixed cylinder or toward each end. Arranged on the circumference and inside the rotating cylinder 72, the wiring of each optical fiber is at a T angle between its both ends and the central axis, or from the first to the (n-th)
/)th wiring fiber /j-7 to 15-(n-/), respectively θOr'θo, 3θ0.・・・・・・．

Arrange the questions so that there are (n-/)00 questions. In the example shown in Fig. 3, the wiring fiber 15-/ connects the input wire /3 and the output wire /3.
Connect the fiber to the fiber 15-2 in the same way.
．． /S-3, 15-1' Elongated cord at 15-6 /3 and outgoing line /l1-2. / Ku 3. The positional relationship of each end face of these fibers /S-/ to /S-6 is shown in FIG. Here, a' is the wiring file/
(Fft1 on both sides of ls -i, also b-made b'.

C and c', d and dl, and e' are both end faces of the twisted fiber /S-λ, 15-3, /S-J. F −F', (J
-G' and H-H' are the reference lines, and the reference line 1i'-
The angle between F' and G-G' is 60 degrees, and the angle between reference line GG' and H-H' is also 60 degrees. End faces a, b and c, c and d.

The angle α formed by the angles d and e is the total rotation angle, and in the case of the /X6 integer in this example, α260/(!+/) = /θ degrees. Both ends m1a and a' of the optical fiber 15-/receive the light from the girder-filled cylinder/3 when the rotary cylinder/no is rotated l pinch clockwise from the position of bo in FIG.
It is placed on the workpiece leading to the outgoing line/guru. 'f, that is, the angle θ1 of the straight line connecting the reference iG G', the end face a', and the rotation axis (center point) is θl-α.

Similarly, θ2-2α, θ3-3α, 04=4tα.

θ5=jα. In the past, for example, in order to connect the input line /3 and the output line /4'-4', the rotary cylinder /2 should be rotated clockwise from the position shown in Figure 5 with a t-pinch rotor.

In order to keep the space between the fixed cylinder // and the rotational circle 'quotient/no from l to μ [n] so as not to interfere with rotation, the coupling efficiency of light is In order to avoid this, a microlens using etching (for example, L, 0.8 vaaa
and, S, Ll'opland and A,
P. Grande.

” Splicing of optical fib
ers with a selective
ng technique, 4Lth EC0C'7
J', pp, 3θll-301) or other conventional techniques may be used in combination.

As is clear from the above explanation, according to the present invention, it is possible to realize an optical switch with low crosstalk, low insertion loss, and a relatively simple drive circuit.

The configuration of the optical switch according to the present invention requires only one section t@ for /xn switches, and uses a reflective prism for /Xn as in the conventional optical switch.
This is very advantageous compared to a switch that requires n2 movable parts in the case of IW and nxl, and the advantage of the present invention increases as the number of lines increases. In addition, because low-loss optical fibers are used for wiring, scattering within the switch is extremely small, making it relatively easy to achieve low crosstalk, which is difficult to achieve with optical switches that use other optical waveguides or liquid crystals. can do. Furthermore, in the present invention,
The optical path can be switched by rotating the disc by the minimum pinch of rotation with a much narrower spacing, without having to rotate the rotating disk by the spacing between the wiring fibers, and the access time can be reduced compared to conventional methods. It is shortened compared to .

[Brief explanation of the drawing]

Figures 7 and 2 are principle diagrams of two examples of conventional fiber-wiring type rotary optical spinches, Figure 3 is a block diagram showing an ixj original spinch as an embodiment of the present invention, and the silk figure is a Figure 5 is a diagram illustrating the upper end surface of the rotary cylinder.FIG. 5 is also a diagram showing the lower end surface of the rotating cylinder. //...Fixed cylinder, /!・One rotation cylinder,
/3... Ice for inserting optical fiber, /ll-7~/'l-3.
・・Optical fiber output line, /S-/
~/S-j...- arranged fiber, a, a/... both end faces of wiring fiber 15-/, b, b'... both end faces of wiring fiber 15-2, e, e'...- Wiring fiber/
Both end faces of s-3, d, d'... wiring fiber/S-≠
Both end faces of e, e'... [- of the wiring fiber 15-j
σ end face, F-F', G-G', H-H'-=Reference i
. Patent applicant: Nippon Telegraph and Telephone Public Corporation Figure 3: 4/4-3 5-F'

Claims (1)

[Claims] 1) An optical switch for connecting a desired line between a plurality of optical fibers and a plurality of optical fibers (including an identification cylinder and a The fixed cylinder has a rotary cylinder which is disposed opposite to the fixed cylinder through a nitrogen gap and can rotate around the same rotation axis as the central axis of the fixed cylinder, and the fixed cylinder has ( n-/,) optical fiber output lines (n is 3
(Divisor of 6θ) The optical fiber input line of the manufactured optical fiber is connected to the rotation of the identified cylinder on the same circumference with both end faces of each of these output wires separated by θo-360/n degrees. The first to (n-/)th wiring lights are arranged on the F exposed on the surface facing the cylinder, and the number of first to (n-/) wiring lights is equal to the number (n-/) of the optical fiber output wires in the co-rotating cylinder No. 111. The fibers are arranged on the same circumference so that both end surfaces of the fibers are exposed on the surface of the rotating cylinder facing the optical fiber-containing scarlet wire, and the optical fiber for wiring is connected to the rotating cylinder. In a circle, the angle between both end surfaces of the wiring optical fiber and the rotation axis, the first wiring optical fiber, the first wiring optical fiber, etc. θ for each of the (n−/)th wiring optical fibers. , 2θ. ,..., arranged so that the angle is (n-/)00 degrees, and the light from the optical fiber input line is passed through a wiring optical fiber selected so as to match the optical fiber input line. , a fiber-wired rotary optical switch 02, characterized in that the optical fiber output line has a conductivity of <15, and the optical switch according to claim 1,
Each end face of the first to (n-/th) distribution optical fibers on the side opposite to the end face of the optical fiber input line is θo/
A fiber wiring type rotary optical inverter is arranged with an angle of (n+/), and the /pinch of the rotation of the rotating cylinder is added to θo/(n+/).