GB2419484A

GB2419484A - Optical N x M switch

Info

Publication number: GB2419484A
Application number: GB0423728A
Authority: GB
Inventors: Zhou Rong
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-10-22
Filing date: 2004-10-22
Publication date: 2006-04-26
Also published as: GB0423728D0

Abstract

An N x M optical switch (OS) comprises 2N identical plates, each having one input, 2M outputs, and at least 2M interconnected micro-switches. The switches are controlled by a computer (Cp) in response to an address, or telephone number, to route optical signals accordingly. The switches function via the electric-magnetic-mechanical or electric-optic effects.

Description

DESCRIPTION OF THE INVENTION

Optic Switch by Means of Electric-magnetic-mechanic Effect Optic Switch by Means of Electric-optic Effect This invention has resolved the problem of full optic communication i.e. the optic switch machine.

I. Electric Switch and Telephone communication Network in Current China A. The electric switch and telephone communication network in china are in figure 1. In the figure, A represents country, B represents province, C represents city, D represents county, E represents town, F represents village, G represents telephone users, the square (small box) represents electric switch machine.

B. The function of electric switch machine (the square in the figure) i. Selection of correct pathway between input and output, so that the speaker and receiver can be automatically connected based on their telephone numbers; ii. Disconnection of the pathway between speaker and receiver as soon as the telephone is hanged over; iii. Telephone response, including timing and pricing; Most electric switch machines only need function in i. And ii., such as international switch, terminal switch, province switch. While some need full function of i.ii.iii. Such as area switch machine, which need timing and pricing. In the figure 1, the connections between electric switches are fully optic fiber, but the switch itself is electronic i.e. electrical switch.

So once we develop optic switch machine, we can acquire full optic communication. In this case, human communication capacity can increase thousands times.

II. Optic switch by means of electric-magnetic-mechanic effect A. The optic switch machine consists of three parts (see figure 2). In the figure, Cp = computer, which plays role of timing and pricing; 0C = control device, which, by electrically control of gate and optic amplifier, can turn on and off of optic pathway; T = the device which transforms optic signal into electrical signal; am = laser producer or amplifier; dmp = demultiplex; mp = multiplex; 0S = optic switch machine; SOS = single optic switch network; TO = optic mini-switch device; 1) = the gate is close when electric current is on, in this case, the light is reflected into third pathway; 2) = the gate is open when electric current is off, in this case, the light goes straightly into the second pathway; G = gate, its head is a mirror to reflect light, and its motion is controlled by electric-magnetic effect.

B. N x M optic switch machine consists of 2N exactly same single optic switch networks (2N layers).

1. A single optic switch network is in figure 3 (pushing pattern) and in figure 4 (attracting pattern). The two figures are explained as follows: 1) A single optic network (one layer) has one input and 2m outputs, and at least 2m optic mini-switch devices; 2) Every optic mini-switch device (TG) is controlled by a computer i.e. a control device. The control device can intelligently select the correct optic pathway from two of them; 3) Because of the intelligent selection of optic pathway by optic miniswitch device, the input signal can go out from one of 2m output pathways, which is correspondence to the telephone number; 4) The size of a single optic network depends on the number of output (2m) and the manufacture technology; of course the smaller is the better; 5) According to the motion of gate, the optic network can be classified as pushing pattern and attracting pattern. The pushing pattern is more efficient than attracting pattern because it only needs to close one or two gates to shape a single optic pathway. But attracting pattern can also be made into pushing pattern. O is natural output i.e. the output when all gates are off from electric current.

2. Optic mini-switch device (TG see the figure) Every optic mini-switch device consists of three terminals of optic fibers and a mirror gate (silver cover). The output terminal should be made into lens shape (like head of an egg), the shape can avoid light scattering of the output signal. The input terminal should be made into lens shape, which can take more input light. We should try different types of len shape, such as dint, egghead, and a plane. We then select the best one. The gate is controlled by a computer i.e. control device. The light goes straight line when the gate is open; the light is reflected into another optic fiber when gate is closed. Every optic network has 2m groups of gates, which control 2m optic pathways. Every group of gates corresponds to a specific telephone number, and controlled by the control device. In this way, the intelligent selection of optic pathway can be precisely and correctly realized. Figure 5, explanation: 1) G = gate, consists of a silver covered mirror and an electric-magnetic-mechanic effect device. 2) Three optic fiber terminals with lens shapes described in above. 3) In the figure 5, the angle and distance should be adjusted into the best sizes, which work most efficiently and can be produced easily.

So, the intelligent selection of optic pathways in optic switch is similar to the space exchange or line selection mechanism in electric switch. While the timing exchange or timing selection mechanism in electric switch is similar to the situation that a single fiber can go hundreds of signals at the same time: at the terminal, one light frequency is represented by one telephone; a user with hundreds of telephones only needs one optic fiber to deliver signals. It only needs the devices for multiplex and demultiplex, no switch machine needed.

3. The structure and the working principle of gate Working principle: the electric-magnetic-mechanic device controls the motion of gate, which controls the on and the off of two light pathways.

The structure of gate can be classified into three (select the most appropriate one at the time of manufacture): f 1) Vertical and attraction device, see figure 6, explanation as follows: a) The structure of gate: consists of electro-magnetic device (SN), spring (S), silver mirror gate, and the bar fixing the gate.

b) When electric current is off, the optic signal is reflected into the nearby optic fiber; c) When electric current is on, the electro-magnetic force attracts the gate moving up and the light signal goes straight line; d) Side view of the gate device; e) Gate structure must be precise and made with good material for sustained rubbing. The gate should be made into the whole structure, and can be vertically put into and fixed in the cross point. So the outside looking of the optic mini-switch with vertical device should be like those in figure 7.

f) The size of the gate is flexible and adjustable. Reflect mirror: high l.5mm, long2.5mm, bar high 8mm, bar crossing area lxlmm. The smaller the better.

g) Gate steel bar must have a small and precise fixing structure (not in figure), to precisely fix the position and angle of the mirror.

2) Parallel attracting device, see figure 8 In figure 8, Fe = electromagnetic steel bar, S= spring, Fp = fixed point, FFe = fixed steel bar.

Explanation: a) When electric current is off, the light signal is reflected into nearby optic fiber; b) When electric current is on, the light signal goes straight line. The Fe must have strong electro-magnetic force when current is on, and has no any remained electro-magnetic force when current is off.

c) The size is flexible and adjustable. The smaller the better.

3) Parallel pressing device, see figure 9 (also see fig 9 pattern 2). This is the most efficient device. But all other devices can also be made into this type with a little structure change.

Explanation: a) When electric current is off, the light signal goes straight line; b) When electric current is on, the light signal is reflected into nearby optic fiber; c) The appearance of the parallel devices is in figure 10; d) The optic mini-switch device must be made precisely in its structure. The size is adjustable. The smaller the better.

The gate is closed when attracting type devices are in nature state (no current, output O); the gate is open when pressing type device are in nature state (no current). SO the switch logic in the single switch network plate is different. For convenience, in a single optic switch network plate, all mini-switch devices are either attracting type or pressing type.

The plate made with all parallel pressing devices (high efficient type) is in figure 3. The plate made with all attracting devices is in figure 4.

C. Control device for switch pathways (OC) is in figure 2.

Its function: 1) Recognize the input telephone number, and turn on the corresponding electric current according to the number, in order to open the corresponding group of optic gates; 2) Recognize the phone hanging up signal and immediately open or close the corresponding gates.

Its working principle: 1) When no light signal comes in, every reflect mirror gate in switch network plate is in nature state i.e. either open or close. At this time, signal is output from 0 fiber.

2) When light signal comes in, a shared branch of optic fiber delivers optic signal into optic electrical transformation device T and the electric signal is sent into OC the control device for switch pathways.

3) OC the control machine for switch pathways is a small computer, which can recognize input telephone number, and turn on the electric control button, which is correspondence to the number. The electric control button has connection with a specific group of gates and their corresponding optic amplifiers (AM). As the result, the specific group of gates which is correspondence to the telephone number is opened or closed. The optic signal then is transferred in corresponding optic fiber and amplified by the corresponding amplifier. The control machine for switch pathways has simple function and can be made into small and elegant.

D. The third part of the optic switch: computer, its function is pricing and telephone response.

The computer is same as the computer used in current electric switch machine.

E. A few key questions about full optic communication 1) Due to the specialty of light transmission, the input and output of an optic switch machine are all in one direction, while current electric switch machines are all two directions.

One direction of light transmission can increase the efficiency of light transmission.

While intelligent selection light pathway means that any input can select any output, which is correspondence to the telephone number.

2) NxM optic switch machine has 2N exact same switch network plates, and each plate has same 2M outputs. Each output light has to be amplified and the outputs at the same position from 2N different plates have to be multiplexed, after amplification, into one optic fiber, (see figure 2). The number of multiplexing at the same position of plates can be 1 to 2N, depending on need and controlled by computer.

3) The basic process of full optic telephone communication is in figure 11: a) Each telephone has two lines, one input and one output, one direction transmission. When we dial in one telephone, the signal is transmitted into another telephone in one line and one direction. When transmitted signal reaches switch machine, which is busy, the signal automatically return to original telephone and the return line becomes second line of the telephone.

b) The two directly connected optic switch machines must have one-to-one correspondence relation between their connected input and output.

c) When dial signal is transmitted to the final (or receiver) optic switch machine and the receiver telephone is recognized as available, the receiver optic switch machine will turn on the corresponding optic pathway and send ring signal to the receiver telephone. At the same time, the machine sends the signal back to the original telephone to form the second telephone line.

d) Optic switch machine can also be designed into two-direction connection at the same time: one switch network plate shapes a pathway to receiver, and the patterner plate shapes the back pathway to original telephone; e) There is no problem to form the return pathway i.e. second pathway, because all optic switch machines have 2N plates. While each communication needs two plates at the same time.

f) The signal transmission capacity of optic switch machine is very big. There is no problem to have globe telephone meeting or lecture, or movies.

III. Optic Switch by Means of Electro-optic Effect 1. Structures and Working Principle The structure and working principle in optic switch based on electro-optic effect and in optic switch based on electro-magnetic-mechanic effect are the same. The only difference between the two switch machines is in structure and working principle of the mini-switch devices, which make up the whole switch network plate. The structure and working principle in mini-switch device based on electro-optic effect are: The material with electro-optic effect will change its light deflect angle or pathway when it receives external voltage. So by the selection of voltage its volume and direction, we can intelligently select light pathway.

There are three types of this kind of materials: 1) Solid crystals, which change its light deflect angle under external voltage. See figure 12.

Explanation: SC = solid crystals, light pathway is changed when voltage direction is changed.

2) Liquid crystals which changes it's deflect angle under external voltage. See figure 13.

Explanation: a) Full reflection when no electric voltage, b) Full deflection under electric voltage, c) LC = liquid crystal. There is such report: see figure 14, explanation of the figure: a) A kind of transparent materials; b) full reflection without electric voltage; c) full deflection under external voltage; d) ferroelectrics liquid crystal, can be connected with external voltage, figure 14 shows an excellent mini- switch device based on electric-optic effect.

Therefore the key problem is to find out a kind of electro-optic effect materials, which is perfect to be used in mini-optic switch device, and with small light loss. These materials include All kinds of optic fiber materials, LiNbO3, InP, InP03, GaAs, GaAsO3, H20, NaNbO3, (PbO.09LaO.91)(ZrO.65Tio.35)03, Ferroelectric liquid crystals, or other liquid crystal.

If some one in future find out a kind of electro-optic effect material which is perfect to be used in mini-optic switch device, his/her discovery also belongs to the scope of the right of this invention, because this invention provides research topic, design, method and the significance of its social utility. But we will recognize and accept hislher contribution.

3) Solid crystals Some solid crystals, especially semi conduct crystal, are transparent or semi transparent to light under specific external voltage. The light will totally be absorbed without external voltage. This kind of materials, such as InP, InP03, GaAs, can be effectively used in optic mini-switch. But a lot of light will be lost in the switch (see figure 15). Explanation: a) light goes through the material under external voltage; b) light is absorbed without external voltage.

Finally, I have to indicate that transparent electrons can be used in optic mini-switch device. It can produce stronger electro-optic effect. See figure 16, explanation: a) transparent electrons, b) the material with electro-optic effect, c) light.

IV. One input and multi-outputs If the mini-switch device is made into the one in figure 17, one optic input can have multi-outputs, one person can communicate with several others at the same time. In figure 17, (1) two electric current are on, two gates are open and there are two optic outputs; (2) (3) one electric current is on, one gate is open, one optic output.

Conclusion:

1. The working principle and the technology of optic switch machine based on electro-magnetic-mechanic effect have been resolved in this invention, but the manufacture technique and precise requirement need to be further developed. The principle is the smaller the better.

2. The working principle and the technology of the optic switch based on electro-optic effect has also been solved. But we need to select the materials, which have perfect electro-optic effect and can be efficiently used in optic mini-switch. So the machine can be used in real communication of our every day life.

3. At the current stage of full fiber communication, we still can use some facility of current electric switch, such as computer.

Claims

CLAIMS: THE REQUESTED RIGHTS IN THE INVENTION 1. High-efficient full optic

communication must be signal one-direction transmission in light pathway. Every light pathway only allows one- direction signal transmission; optic switch machine must be one side input and another side output; telephone two lines must be one input and another output. Of course full optic communication can also be made into two-direction communication, but the efficiency will be decreased.
2. The structure and principle of optic switch machine. The machine consists of three parts: computer, control device for optic pathway (control of the optic mini-switch), optic switch network plates and their working principle. My contribution is the structure and working principle of the optic switch network. A NxM optic switch machine consists of 2n exact same optic switch network plates. Every network plate has one input and 2m outputs, and has at least 2m mutual connected mini-switch devices. Every mini-switch device is controlled by a mini-computer (control device for optic pathway) and can intelligently select light pathway based on telephone number. So every input signal can select any output pathway, which is consistent with the telephone number. In this way the signal can precisely arrive the intended telephone represented by the number.
3. The structure and working principle of optic mini-switch devices, and the research design based on the structure and the principles. Two types: Computer-controlled optic mini-switch by means of electric-magneticmechanic effect; Computer-controlled optic mini-switch by means of electric-optic effect.
4. I have identified following electric-optic effect materials, which can be used in optic mini-switch device: All kinds of optic fibber materials, LiNbO3, Ferroelectrics liquid crystal, H20, NaNbO3, InP, InP03, GaAs, GaAsO3, CaSiO3, (PbO.09LaO.91)(ZrO.65TiO.35)03, so on.
5. The idea and working principle of control machine for optic pathway, and the research design based on the idea and the principles. #