JPS6232443B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical switch device that ensures reliable determination of the presence or absence of a signal.

An optical switch device separates wavelength-multiplexed light transmitted from a light source through an optical fiber into light of each wavelength using a plurality of interference thin-film filters, and separates the light of each wavelength from a corresponding light shielding member. This device is configured to transmit or block light through an optical switch and generate a desired signal state depending on the presence or absence of light of each wavelength. The light of each wavelength that has passed through each optical switch is multiplexed again by a multiplexing interference thin film filter, and then output from the optical switch device.
It is transmitted to the processing circuit via optical fiber. In the above description, each optical switch is configured to be linked to the operation of a predetermined operating means of various electrical devices, so that it is possible to detect various signal states in the processing circuit.

However, since optical switch devices use the presence or absence of light of a predetermined wavelength as a signal, leakage light may occur even when it is determined that light is present, so in reality There may also be cases where it is extremely difficult to determine whether it is signal light or leakage light.

Therefore, in view of the above-mentioned problems in optical switch devices, the present inventors have created the present invention in order to effectively solve the problems.

An object of the present invention is to clearly define transmission and blocking by each optical switch in an optical switch device that uses wavelength-multiplexed light as a signal medium and generates a desired signal state depending on the presence or absence of light of each demultiplexed wavelength. The objective is to improve the reliability of signal discrimination.

In order to achieve the above object, the present invention provides an optical switch device that has an entrance surface that allows each wavelength-multiplexed light to enter separately, and has a double-sided demultiplexing function corresponding to each wavelength of the wavelength-multiplexed light. a demultiplexer including a demultiplexing element having a demultiplexing element, and two multiplexers for separately re-multiplexing each wavelength multiplexed light, between the demultiplexer and each of the two multiplexers. The gist thereof is that the opening/closing means are connected so that the pairs of opening/closing means which transmit and block light of each wavelength are arranged in opposite directions.

A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows the configuration of an optical switch device according to the present invention, and FIG. 2 shows A in FIG.
It is a directional view.

In Figure 1, the wavy lines indicate the traveling path of light,
Originally, light is transmitted by being guided through an optical transmission line such as an optical fiber, but the optical transmission line is omitted from the figure to simplify the illustration. L ₁ is input light, which in this embodiment is wavelength-multiplexed light consisting of lights of wavelengths λ ₁ , λ ₂ , and λ ₃ . The input light _L1 is
2 and 3 in the figure by a half mirror or optical coupler 1.
It is configured such that the light passing through two paths is separated at a rate of 50% each, and each is input to the demultiplexer 4 of the optical switch device.

The optical switch device section 5 includes a demultiplexer 4, two demultiplexers 6 and 7 arranged in parallel on both sides of the demultiplexer 4,
The light blocking member 81, 82, 83, 91, 92, 93 is provided between the demultiplexer 4 and each demultiplexer 6, 7 to correspond to each wavelength of light, and is capable of opening and closing operations. The demultiplexer 4 includes three demultiplexing interference thin film filters 41 and 4 corresponding to the number of wavelengths of light to be multiplexed.
In this embodiment, the interference thin film filter 43 transmits wavelengths λ ₁ and λ ₂ and transmits wavelengths λ 3 and λ ₃ .
The interference thin film filter 42 reflects the wavelengths λ ₁ and λ
The interference thin film filter ₄₁ transmits wavelengths λ ₂ and λ ₃ and reflects wavelengths λ ₂ and λ _{1 .}
It has the property of reflecting. These interference thin film filters 41, 42, and 43 are formed so as to exhibit the above-mentioned characteristics even if wavelength-multiplexed light is incident on either the front or back surface.
Therefore, in the demultiplexer 4, incidence surfaces for the wavelength-multiplexed light _L1 are formed on both end surfaces 4a and 4b, and exit surfaces are formed on side surfaces 4c and 4d perpendicular to these, and the above-mentioned paths 2 and 3 are formed. As shown in the figure, the guided input light _L1 is input to the end surface 4a in path 2, and into the end surface 4b in path 3, and is further input to the side surfaces 4c, 4b, respectively.
It is configured to be emitted from 4d.

In contrast to the demultiplexer 4, the multiplexers 6 and 7 include multiplexing interference thin film filters 61, 62, 63, 71,
72 and 73, and an interference thin film filter 6 for multiplexing.
1 and 71 face the interference thin film filter 41 for demultiplexing, and similarly filters 62 and 72 face the filter 4.
2, the filters 63 and 73 are arranged to face the filter 43, respectively. Filter 6
The filter characteristics of filters 1 and 71 are those of filter 41, and the filter characteristics of filters 62 and 72 are those of filter 42.
The filter characteristics of the filters 63 and 73 are the same as that of the filter 43, respectively. The lights of each wavelength that have passed through the multiplexers 6 and 7 are multiplexed, and the output of the multiplexer 6 passes through the path 10 as the first output _O1 , and the output of the multiplexer 7 passes through the path 11. 2nd output through O ₂
are output as respectively.

And interference thin film filters 41, 42 for demultiplexing,
43 and each of the multiplexing interference thin film filters 61, 62, 63, 71, 72, 73 of each multiplexer 6, 7, which are movable so that light of each wavelength passing between them can be transmitted. or a light shielding member 81 for blocking,
82, 83, 91, 92, 93 are provided, and as is clear from FIG.
1, 82 and 92, 83 and 93 are connecting rods 12, 1 that are swingably attached to the central position as a fulcrum.
3 and 14 are combined and integrated. Such a structure has a characteristic that if any one of the light shielding members 81 and 91, 82 and 92, 83 and 93 is in a transmitting state, the other is always in a blocking state. Therefore, for example, the light shielding members 81, 82, and 83 are configured to transmit or block light of each wavelength in conjunction with respective corresponding predetermined operating means, etc., to form a light switch, while the light shielding members 91, 92 ，
93 generates a signal state that is completely opposite to the signal state generated by the light shielding members 81, 82, and 83.

In FIGS. 1 and 2, numerals 15, . . . are lenses that converge or make the light parallel.

In the above configuration, the optical switch device according to the present invention operates as follows.

The lights at wavelengths λ ₁ , λ ₂ , and λ ₃ emitted from three light sources (not shown) are multiplexed and combined into input light.
It becomes L ₁ and is transmitted to half mirror 1, etc. The input light L ₁ is separated into two in the half mirror etc. 1, one input light L ₁ passes through the path 2 and enters the splitter 4 from the end face 4a, and the other input light L ₁ passes through the path 3. It enters the duplexer 4 from the end face 4b. The input light L ₁ entering the demultiplexer 4 from the end face 4 a is separated into lights of wavelengths λ ₁ , λ ₂ , and λ ₃ by the right side surfaces of the interference thin film filters 41 , 42 , and 43 as described above. , and are transmitted to the multiplexer 6 after passing through each optical switch composed of corresponding light shielding members 81, 82, and 83 via the side surface 4c. The light of each wavelength that has passed through each optical switch is multiplexed again by the multiplexing interference thin film filters 61, 62, and 63 of the multiplexer 6, and is outputted on a path 10 as wavelength-multiplexed light. In the above, the light shielding members 81, 82, 83 disposed between the duplexer 4 and the multiplexer 6 open and close in conjunction with corresponding operating means (not shown), and are in a transmitting or blocking state. Therefore, it is possible to obtain a predetermined detection signal related to the state of the object to be detected depending on the presence or absence of light of each wavelength λ ₁ , λ ₂ , λ ₃ in the wavelength multiplexed light output from the multiplexer 6 .

Input light L ₁ entering the splitter 4 from the other end surface 4b
, each wavelength λ ₁ ,
It is separated into light of λ ₂ and λ ₃ , and passes through the side surface 4d.
The multiplexer 7 and the light shielding members 91, 92, 93 between the demultiplexer 4 and the multiplexer 7 are used in the same manner as described above, depending on the presence or absence of light with wavelengths λ ₁ , λ ₂ , and λ ₃ . The light is then outputted on path 11 as wavelength-multiplexed light forming a detection signal.

In the above, the output O ₁ from the multiplexer 6 via path 10 and the output O ₂ from the multiplexer 7 via path 11
The signal states of each wavelength in , based on the above-described configuration, occur in exclusive states, ie, in contradictory states. Therefore, the output as shown in Figure 3
After converting O ₁ and O ₂ into electrical signals, by inputting them to each input terminal of the comparator 16 and comparing them, signals related to light of each wavelength at the outputs O ₁ and O ₂ can be extracted. It is possible to reliably determine the presence or absence of a signal related to a wavelength. The determination of the presence or absence of such a signal is generally performed in the signal processing circuit 17 at the end of the paths 10 and 11 under electrical signal processing.

The optical switch device according to the present invention is not limited to the above-mentioned embodiments. For example, the number of wavelengths of wavelength-multiplexed light can be increased, and two light sources can also be provided, and each wavelength-multiplexed light can be separated by a demultiplexer. may be configured to be input separately.

As is clear from the above description, according to the present invention,
In an optical switch device that generates a predetermined signal state using wavelength-multiplexed light, the presence or absence of light of each wavelength passing through each light-shielding member is determined based on a pair of light-shielding members that are exclusively opened and closed. This method has the advantage that the state of the light shielding member to be detected, that is, the signal state, can be accurately determined by comparing the two signals.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an optical switch device according to the present invention, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. 3 is a circuit diagram for determining the presence or absence of a signal. In the drawing, 1 is a half mirror or optical coupler, 4 is a demultiplexer, 6, 7 is a multiplexer, 81, 82, 83, 9
1, 92, and 93 are light shielding members.

Claims (1)

[Claims] 1. Demultiplexing wavelength-multiplexed light into light of each wavelength using a demultiplexer,
An optical switch device configured to transmit or block light of each wavelength using individual opening/closing means and multiplexing the light again using a multiplexer, the optical switch having an entrance surface that allows each of the wavelength-multiplexed lights to enter separately; a demultiplexing element having a double-sided demultiplexing action corresponding to each wavelength light of the wavelength-multiplexed light, and into which each of the above incident lights is incident from both sides; a demultiplexer having an exit surface for emitting light; two multiplexers that receive the light emitted by the demultiplexer and separately multiplex the wavelength-multiplexed lights; and the demultiplexer and the two multiplexers. consisting of a plurality of opening/closing means arranged between each of the multiplexers and connected so that the pairs of opening/closing means transmitting and blocking light of each of the wavelengths can take opposite states; An optical switch device featuring: