JPS61132918A - Method for switching optical transmission line without momentary break and its optical switch - Google Patents

Abstract

PURPOSE:To switch an optical transmission line without a momentary break resulting no interruption of an optical signal by moving an optical control plate, which has a full transmission area, a half transmission area, and a total reflection area of light continuously, to switch the optical transmission line. CONSTITUTION:Lenses 9-12 of an optical switch are arranged on two optical axes, and optical fibers are coupled to them respectively. An optical control plate 13 is so provided that it passes the intersection between these optical axes and can be moved at 45 deg., and a full transmission area 13a, a half transmission area 13b, and a total reflection area 13c of light are formed continuously on the control plate 13. Normally, the full transmission area 13a is used, and a transmission line 2 is used by lenses 9 and 11; but if the transmission line is faulty, the control plate 13 is moved, and the optical signal is divided to lenses 10 and 11 by the half transmission area 13b, and thereafter, the transmission line is switched to a transmission line 4 by the total reflection area 13c. Thus, the optical transmission line is switched without the momentary break not to interrupt the optical signal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Technology) The present invention relates to a method of switching a section of an optical transmission line to an optical transmission line of another route without momentary interruption of the first optical signal, and an optical switch used in the method.

(Prior Art) Conventionally, in an optical transmission line using an optical fiber, when it becomes necessary to secure an optical transmission line for a certain section due to a failure or relocation of the optical transmission line, (1) mirror or lens (2) switching using a connector; and (3) switching using an il@ connection means.

(Problems to be Solved by the Invention) However, in any of the above methods, as shown in FIGS. 1 to 3, the optical fiber 1.2.3 in use is
It is necessary to cut the optical fiber at the connection points 5 and 6 and connect it to the optical fiber 4 at the connection points 7 and 8. There was a problem in that communication was interrupted until the connection was completed.

(Objective of the Invention) In order to solve the above-mentioned problems, the first object of the invention is to provide a method for switching a section of an optical transmission line to an optical transmission line of another route without momentary signal interruption. A second object of the invention is to provide an optical switch that provides continuity in switching used in the above method.

(Means for Solving the Problems) In order to achieve the above object, the first invention provides a fully transparent area and a semi-transparent area for light from one end side to the other end side.

Light 1IIyll in which total reflection areas are continuously provided in the order listed.
A plane that passes through the intersection of two optical axes crossed at an arbitrary angle α, is perpendicular to a plane containing the two optical axes, and connects the two optical axes to 2.
Using an optical switch arranged so as to be able to move continuously on a plane positioned at an equal dividing angle (α/2),
The optical switch is optically coupled in advance at appropriate intervals of the optical transmission line so that the optical axis of the optical transmission line and one optical axis of the optical switch coincide, and the optical control board of the optical switch is normally connected. If optical signals are transmitted through the entire transmission area of the optical transmission line, and if a different route optical transmission line is required due to a failure of the optical transmission line or troublesome relocation, etc., the other optical signals of the optical switches before and after the section in question are transmitted. After the front and rear terminals of the optical transmission line for another route are arranged on the axis and optically coupled, the total reflection area of the optical board of the optical switch is moved to the intersection position. In addition, in order to achieve the above object, the second invention provides a light control plate in which a total light transmission area, a semi-transmission area, and a total reflection area are successively provided in the order described from one end side to the other end side. arbitrary angle α
The angle (α/2
) so that it can move continuously on a plane located at

(Function) According to the instantaneous interruption switching method of an optical transmission line according to the present invention, in the process of moving the optical control board of the optical switch, the light is transmitted through the semi-reflective area between existing optical transmission lines and between existing optical transmission lines. Since the optical signal can be transmitted between the remaining optical transmission line and the optical transmission line of another route, although there is a level fluctuation of the optical signal of about 3 dB, the light reflectance or light transmittance of the optical control board will change. By making the speed of change slower than the AGC response speed of the transmission device, the optical transmission path can be switched without interrupting the optical signal. Further, according to the optical switch according to the present invention, the above-described method can be easily and accurately implemented.

(Example) FIG. 4 is a diagram explaining the principle of the optical switch of the present invention, and FIG. 5 is a perspective view schematically showing the optical switch. In the figure, 9.10.
Reference numerals 11 and 12 denote lenses, which are disposed on two orthogonal optical axes A and B and spaced apart from each other by a predetermined distance around the intersection C thereof, and are supported by suitable support means (not shown). There is.

An end of an optical fiber constituting an optical transmission path can be optically coupled to the end surface of each of the lenses 9 to 12 on the opposite side to the facing surface. 13 is a light control board, which is a rectangular shape.
From one end of a translucent plate such as a lath plate to the other end, there are a total light transmission area 13a, a semi-transmission area 13b, and a total reflection area 13.
c are successively provided in the order listed.

Note that the semi-transmissive region 13b or the total reflection region 13C can be easily realized using known manufacturing techniques for the half mirror 2 or total reflection mirror. Alternatively, a half mirror and a mirror may be combined with a translucent plate. This light control board 1
3, each optical axis A,
It is movably arranged on a plane that maintains an angle of 45° with respect to B. 15 is a plunger solenoid supported by a suitable support means (not shown); 15a is its operating rod, which is connected to the other end of the light control plate 13 via a connecting rod 16; Light control board 1 during operation
The center part of the total transmission area 13a of No. 3 is located at the intersection C,
Further, during operation, the central portions of the total reflection areas 13G move to the positions of the intersections C, respectively. 17 is a guide member that ensures the movement of the light control plate 13 as described above.

Since the optical switch according to the present invention is configured as described above, in the initial state, as shown in FIG. Thereafter, by applying a signal to the solenoid 15 and activating it, the light control plate 13 moves, and as shown in FIG. (14'
.

Then, as shown in FIG. 8, the light 14 is transmitted to one of the optical axes orthogonal to the other optical axis via the total reflection region 13c.

Next, a method of switching an optical transmission line without momentary interruption using the optical switch as described above will be explained with reference to FIGS. 9 to 1'1. In addition, in FIGS. 9 to 11, for the sake of simplification,
Only the main parts of the optical switch are shown diagrammatically, and the other constituent parts are shown diagrammatically. In the figure, 1.2.3 is an optical transmission line made of optical fiber. The optical switch is interposed in advance between the optical transmission lines 1 to 3. That is, one end of the optical transmission line 1 is connected to the lens 9 of one optical switch, each end of the optical transmission line 2 is connected to the lens 11 of one optical switch and the lens 9 of another optical switch, and one end of the optical transmission line 3 is connected to the lens 9 of one optical switch. They are each optically coupled to lenses 11 of other optical switches. In this state, if the total transmission area 13a of the optical control board 13 of the double optical switch is located at the intersection of the optical axes, the optical signal will be transmitted between the optical transmission lines 1 to 3 via the total transmission area 13a. do. If an optical transmission line of a different route is required due to a failure of the optical transmission line or a troublesome relocation, etc., one end of the optical transmission line 4 made of an optical fiber of a different route is connected to the lens of an optical switch, as shown in Fig. 9. 10, and the other end is optically coupled to a lens 12 of another optical switch. After that, if a signal is applied to each optical switch and they are activated at the same time, the light control plate 13 starts moving as shown in FIG.
The optical signal can be transmitted to the existing optical transmission line 1-2-3 route and the optical transmission line 1-4-3 route through the optical transmission line 1 through the total reflection area 13G as shown in FIG. Optical signals can be transmitted through the -4-3 route. At this time, although there is a level fluctuation of the optical signal of about 3 dB, the speed of change in the optical reflectance of the optical control board 13 is controlled by the AGC of the transmission device.
By making it slower than the response speed, the optical signal will not be interrupted.

In this state, if the optical control board 13 is returned to its original position after reconnecting the optical transmission line 2 or repairing the problem, it is possible to switch to the optical transmission line 1-2-3 route without any interruption. can.

Although lenses 9 to 13 were used in the above embodiments, the present invention can be carried out without using lenses 9 to 13, although some light scattering occurs. Further, although the light control plate 13 is driven by a solenoid, other driving means may be used or manual operation may be used.

(Effects) As explained above, according to the first invention, the light control plate is provided with a total light transmission area, a semi-transmission area, and a total reflection area in the order described from one end side to the other end side. , any angle α
An angle (α/
2) using an optical switch arranged so as to be able to move continuously on a plane located in 2), the optical switch is aligned in advance with the optical axis of the optical transmission line at appropriate intervals of the optical transmission line. The optical switch is optically coupled so that the two optical axes coincide with each other, and the optical signal is normally transmitted through the entire transmission area of the optical control board of the optical switch. If an optical transmission line for a route is required, after placing the front and rear terminals of the optical transmission line for another route on the other optical axes of the front and rear optical switches that include the relevant section and optically coupling them,
Since the total reflection area of the optical control board of the optical switch is moved to the above-mentioned intersection position, in the process of moving the optical control board of the optical switch, the light is transmitted through the semi-reflection area between existing optical transmission lines as well as existing optical transmission lines. Since the optical signal can be transmitted between the remaining optical transmission line and the optical transmission line of another route, although there is a level fluctuation of the optical signal of about 3 dB, the optical reflectance or optical transmittance of the optical control board By making the rate of change slower than the AGC response rate of the transmission device, the optical transmission line can be switched without interrupting the optical signal. Furthermore, since there is no momentary interruption, the timing of switching can be selected regardless of the presence or absence of a signal even during the transmission of a digital signal.

According to the second invention, a light control plate in which a total light transmission area, a semi-transmission area, and a total reflection area are successively provided in the order described from one end to the other end is intersected at an arbitrary angle α. The plane that passes through the intersection of the two optical axes and is perpendicular to the plane containing the two optical axes and
Since it is arranged so that it can move continuously on a plane located at an angle (α/2) that bisects the optical axis of the book, it is possible to provide continuity in switching, and the above-mentioned method can be simplified and It has the advantage of being able to be realized accurately.

[Brief explanation of the drawing]

The drawings are for explaining the present invention, and FIGS. 1 to 3 are explanatory diagrams of a conventional optical transmission line switching method, FIG. 4 is a diagram showing the principle configuration of an optical switch according to the present invention, and FIG. 6 to 8 are perspective views showing one embodiment of the optical switch according to the present invention.
The figures are explanatory diagrams of the operation of the optical switch of the present invention, Figures 9 to 11.
The figure is an explanatory diagram of a method for switching an optical transmission line without momentary interruption according to the present invention.

Claims (2)

[Claims] (1) Two light control plates, each of which has a total light transmission area, a semi-transmission area, and a total reflection area continuously provided in the order listed from one end to the other, are crossed at an arbitrary angle α. A plane passing through the intersection of the optical axes and perpendicular to the plane containing the two optical axes, and connecting the two optical axes to 2
Using an optical switch arranged so as to be able to move continuously on a plane positioned at an equal dividing angle (α/2),
The optical switch is optically coupled in advance at appropriate intervals of the optical transmission line so that the optical axis of the optical transmission line and one optical axis of the optical switch coincide, and the optical control board of the optical switch is normally connected. If optical signals are transmitted through the entire transmission area of the optical transmission line, and if a different route optical transmission line is required due to a failure of the optical transmission line or troublesome relocation, etc., the other optical signals of the optical switches before and after the section in question are transmitted. Optical transmission characterized in that after the front and rear terminals of the optical transmission line for different routes are arranged on the axis and optically coupled, the total reflection area of the optical control board of the optical switch is moved to the intersection position. A method for switching the road without momentary interruption. (2) Two light control plates each having a total light transmission area, a semi-transmission area, and a total reflection area continuously provided in the order listed from one end to the other end are crossed at an arbitrary angle α. It is arranged so that it can move continuously on a plane that passes through the intersection of the optical axes and is perpendicular to the plane that includes the two optical axes and is located at an angle (α/2) that bisects the two optical axes. An optical switch characterized by: