JPH0227311A - Optical terminal equipment - Google Patents

Abstract

PURPOSE:To realize an optical switch having no movable part and to obtain an optical terminal station equipment having high reliability by providing a mercury layer in a glass block, heating and radiating a mercury body by a heater and switching an optical path. CONSTITUTION:A plane plate-like mercury layer 32 is provided on the inside of a transparent glass block 31, and a heater electrode 33 is attached to one side thereof. Usually the mercury layer 32 forms a transmission surface, and an optical signal of a port A is led to a port C. When the heater electrode 33 is heated, the mercury layer 32 becomes a reflecting surface, and the optical signal is reflected to a port B. An optical terminal station is formed by inserting this optical switch between the first and the second half mirrors 1, 2. When the optical switch is a reflecting body, a light beam of the first optical input port is led to the second optical output port, and also, a light beam of the second input port is led to the first optical output port. When the optical switch is a transmission body, the light beam of the first input port can be led to the first output port.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical switching element and an optical terminal equipment for an optical fiber loop network using the optical switching element.

Conventional technology A loop type LAN using optical fibers starts from a center station and connects each terminal in series using optical fibers, as shown in FIG. An optical switch 30 is provided at the connection point of each terminal filtering optical fiber loop, and an input optical signal is normally guided to an optical receiver 4 where it is converted into an optical/electrical signal and processed by a transmitting/receiving device 6. For communication to the next terminal, the transmission signal of the transmitting/receiving device 6 is input to the optical transmitter 5, converted into an electrical/optical signal, and the light emission output signal is sent to the optical fiber loop via the optical switch 30 to the next terminal. It is input to the optical switch 30.

For example, if a terminal becomes unable to communicate due to a failure or the like, the terminals subsequent to that terminal will no longer function, so the failure is detected and the optical switch 30 is put into a bypass (direct) state to maintain loop communication. .

The optical switch 30 includes a reflecting mirror 36 as shown in FIG.
and a rhombic prism 37.

The lens 38 converts the beam light into parallel light and converts the parallel light into beam light. Now, when the rhombic prism 37 is in the position indicated by the solid line, the optical signal at the optical input port 1 is guided to the optical output port 2, and at the same time, the optical signal at the optical input port 2 is guided to the optical output port 1. When the optical switch 30 is placed in the bypass state, the rhombic prism 37 is moved to the position indicated by the broken line to form an optical path indicated by the broken line arrow. The movement of the rhombic prism is achieved by the attraction and repulsion of permanent magnets and electromagnets.

Problems to be Solved by the Invention In this type of optical switch, the lens and reflective mirror are permanently fixed, but the rhombic prism is fixed to a mechanically movable member. When used in an environment with many vibrations, the positional accuracy may change and the optical axis may shift.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide an optical switch element having no moving parts, and an optical fiber loop optical terminal device using this optical switch element. .

Means for Solving the Problems (First Means) In order to solve the above-mentioned problems, the present invention injects and encapsulates a material that expands and condenses with heat into a transparent glass block. This optical member forms a reflecting surface and a transmitting surface by expansion and condensation, and this optical member is inserted and fixed on the optical axis to switch the optical path.

(Second Means) In order to solve the above-mentioned problems, the present invention provides an optical member that forms a reflective surface and a transmitting surface by an electrical reaction of a dielectric material inside a transparent glass block, and sets this optical member to an optical axis. It is inserted and fixed on top to switch the optical path.

(Third Means) In order to solve the above problems, the present invention coats or mixes an optical member that forms a reflective surface and a transmitting surface by irradiating and non-irradiating with light of a specific wavelength on the surface or inside of a transparent glass block. and insert and fix this optical member on the optical axis.
This is to switch the optical path.

(Fourth Means) In order to solve the above-mentioned problems, the present invention provides the above-mentioned first,
The optical switch element obtained by the second and third means is inserted and fixed on the optical axis, and the first means is a combination of the optical switch element and two half mirrors, or the second means is a combination of two optical switch elements. An optical terminal device of an optical fiber loop network is constructed by means of the present invention or a third means using one optical switch element.

Effect: According to the above structure, an optical switch element having no mechanically movable parts can be realized.

Example Embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing the configuration of an optical switch element that is a first embodiment of the present invention. 31 is a transparent glass block, 32 is a mercury layer, and 33 is a heater electrode. The mercury layer 32 is injected in the form of a flat plate, and is usually condensed at the positions indicated by crosshatching, with the hatched area forming a transmission surface. Now, when an optical signal is input from port A, it passes through the transparent surface of the mercury layer and is guided to port C. Next, when the heater electrode is heated, the mercury expands and forms a reflective surface in the shaded area of the mercury layer, so the optical signal is reflected and guided to port C.

(Embodiment 2) FIG. 2 is a block diagram showing the configuration of an optical switch element which is a second embodiment of the present invention. 31 is a transparent glass block, and 34 is a dielectric film layer such as a liquid crystal element or a chromic element. The dielectric film layer is normally transparent and forms a transmitting surface, but when a potential is applied, it develops color and forms a reflective surface.

The optical signal input from A) is switched to port C when the dielectric film layer is transmitting, and to port B when it is reflecting.

(Embodiment 3) FIG. 2 is a block diagram showing the configuration of an optical switch element which is a second embodiment of the present invention. 31 is a transparent glass block, 35 is a specific wavelength reflection film, and 36 is a specific wavelength light source. The specific wavelength reflecting film 35 is normally transparent and forms a transmitting surface, but when irradiated with light of a specific wavelength, it absorbs the component, develops color, and reflects the component of the specific wavelength light, thereby forming a reflective surface. The optical signal input from port A is switched to port c when the specific wavelength reflection film is in a transmitting state, and to port B when it is reflecting.

(Example 4) Next, FIGS. 4 to 6 show examples in which the optical switch elements obtained in the first to third examples above are used in optical terminal equipment of a LAN using optical fiber communication. show. FIG. 4 shows a first example in which an optical switch element and two half mirrors are combined. FIG. 5 shows a second example in which two optical switch elements are combined. FIG. 6 shows a third example using one optical switch element. The operation will be explained below with reference to the drawings.

In FIGS. 4 to 6, the optical switch element 3 is obtained in Examples 1 to 3 above.

In FIG. 4, a half mirror 1 branches an input optical signal almost equally by transmission and reflection. Optical input port 1 and optical output port 1 are connected to optical fiber communication L as shown in FIG.
Connected to the AN's fiber optic loop. The optical output port 2 is still connected to the optical receiver 4, and the optical input port 2 is connected to the optical transmitter 5.

In normal operation, the optical signal a input from the optical input port 1 is split into two by the half mirror 1, and the transmitted light a+ is reflected by the optical switch element 3 and inputted again to the half mirror 1 as an optical signal, and the same The optical signal b+ is split into two
and is guided to the optical output port 2. On the other hand, the optical signal C input from the optical input port 2 is split into two by the half mirror 2, and the reflected light is guided to the optical output port 1 as an optical signal CI.

Next, in the event of an abnormality, the optical switch element 3 functions as a transmitting body, so the optical signal a passes through the optical switch element 3 and is split into two by the half mirror 2, and the transmitted light is output as an optical signal d1 to the optical output port. I am guided by 1.

In FIG. 5, the optical input port 1.2 and the optical output port 1.2 have been described above, so their explanation will be omitted.

In normal operation, an optical signal a input to the optical input port 1 is reflected by the optical switch element 3 and guided to the first output port 2. On the other hand, the optical signal C input to the optical input port 2 is reflected by the optical switch element 3 and guided to the optical output port 1.

Next, in the event of an abnormality, the optical switch elements 3 each function as a transmitting body, so that the optical signal a is transmitted to the optical switch element 3.
are transmitted to the optical output port 1.

In FIG. 6, the optical input port 1.2 and the optical output port 1.2 have been described above, so their explanation will be omitted.

In normal operation, an optical signal a input to the optical input port 1 is reflected by the optical switch element 3 and guided to the first output port 2. On the other hand, the optical signal C input to the optical input port 2 is reflected by the optical switch element 3 and guided to the optical output port 1.

Next, in the event of an abnormality, the optical switching element 3 functions as a transmitting body, so that the optical signal a is transmitted through each of the optical switching elements 3 and guided to the optical output port 1.

Effects of the Invention According to the present invention, it is possible to realize an optical switch element having a simple structure and no mechanically movable members, and it is also possible to provide an optical terminal device that is excellent in terms of reliability and performance.

[Brief explanation of the drawing]

1, 2, and 3 are block diagrams showing the configuration of the optical switch element of each embodiment of the present invention, and FIG. 4, and FIG.
6 is a block diagram showing the configuration of an embodiment of an optical terminal equipment using the optical switching element of the present invention, FIG. 7 is a block diagram showing the configuration of a conventional optical fiber communication LAN, and FIG. The figure is a block diagram showing the configuration of a conventional optical switch. 1.2... Half mirror 3... Optical switch element,
4... Optical receiver, 6... Optical transmitter, 6... Transmitting/receiving device, 30... Optical switch, 31... Glass block, 32... Mercury layer, 33... Heater electrode , 34・
...Dielectric film layer, 35...Specific wavelength reflective film, 36...
・Specific wavelength light source. Name of agent Patent attorney Shigetaka Awano Haka 18 Figure 1 Figure 2 Figure Figure Section LJI)> Totade B-toto

Claims (6)

[Claims] (1) A flat plate-shaped mercury layer is provided inside a transparent block body such as glass, mercury is injected, a heater electrode is fixed to one side of this mercury layer, and the mercury body is expanded or An optical switching element that switches an optical path by condensing light to form a reflective surface or a transmitting surface. (2) A flat plate-shaped dielectric film layer is provided inside a transparent block such as glass, an electrode is fixed to this dielectric film layer, and a light reflecting or transmitting surface is formed by controlling the voltage of the electrode. An optical switching element characterized by switching an optical path by switching the optical path. (3) A transparent block such as glass is coated with or mixed with a material that develops color by absorbing light of a specific wavelength and reflects light of a specific wavelength, and is identified by irradiating it with a light source of a specific wavelength from the outside. An optical switching element characterized by forming a reflecting surface for wavelength light and forming a transmitting surface when irradiation is stopped to switch the optical path. (4) a first half mirror having a first optical input port and a second optical output port;
a second half mirror having an optical output port is inserted and fixed obliquely to the optical axis on the optical axis connecting the first optical input port and the first optical output port, and An optical switch element that reflects or transmits light depending on the presence or absence of voltage application is inserted and fixed in the middle of the half mirror at right angles to the optical axis, and by using the optical switch element as a reflector under the first condition, the first guiding the optical signal of the optical input port of the optical input port to the second optical output port and guiding the optical signal of the second optical input port to the first optical output port, and using the optical switch element as a transparent body under the second condition. The optical switching element according to claim 1, 2, or 3 is configured to guide the optical signal of the first optical input port to the first optical output port. Optical terminal equipment. (5) a first optical switch element that includes a first optical input port and a second optical output port and that performs reflection or transmission;
A second optical switch element having a second optical input port and a first optical output port and capable of reflection or transmission is arranged on an optical axis connecting the first optical input port and the first optical output port. The optical switch is inserted and fixed obliquely to the optical axis, and the optical signal from the first optical input port is guided to the second optical output port by using the first and second optical switching elements as reflectors under the first condition. and guide the optical signal of the second optical input port to the first optical output port, and under the second condition, the optical signal of the second optical input port is guided to the first optical output port.
Claims 1 and 2 are characterized in that the optical signal of the first optical input port is guided to the first optical output port by using the second optical switch element as a transmitting body. An optical terminal device using the optical switch element according to item 2 or 3. (6) The first optical switch element is reflective or transparent.
The optical switch element is inserted and fixed obliquely with respect to the optical axis connecting the optical input port and the first optical output port, and on the reflective surface of the optical switch element, the first optical input port and the second optical output port are connected to the optical axis. The second optical input port and the first optical output port are arranged so that their optical axes coincide with each other, and under the first condition, the optical signal of the first optical input port is transferred to the first optical input port using the optical switch element as a reflector. The optical signal of the second optical output port is guided to the second optical output port, and the optical signal of the first optical input port is guided under the second condition using the optical switch element as a transmitting body. An optical terminal device using the optical switch element according to claim 1, 2, or 3, characterized in that it is configured to guide the optical signal to the first optical output port.