JPH09152512A - Optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deterioration in performance and trouble by humidity with simple constitution of a small number of parts by housing optical parts together with fluoride glass optical fiber ends into a hermetic container and removing moisture from this hermetic container, thereby constituting this optical device. SOLUTION: This optical device has the fluoride glass optical fiber, optical parts connected to the fluoride glass optical fiber and the hermetic container which houses the optical parts removed of moisture from the inside together with the ends of the fluoride optical fiber. Namely, the hermetic container 11 packed with, for example, an inert gas 11g internally houses the Pr added fluoride glass optical fiber 1, an exciting light source 4, a WDM coupler (optical multiplexer/demultiplexer, optical parts) 5, the optical isolator 6 and the quartz glass optical fiber 7 for connecting these parts and junctures 2, 3. As a result, the deterioration in the performance and trouble of the respective optical parts by the moisture and external impact are prevented simply by using one piece of the hermetic container 11 as the housing container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device such as an optical amplifying device and an optical transmission device using a fluoride glass optical fiber.

[0002]

2. Description of the Related Art As one type of optical fiber used for transmitting light, there is a fluoride glass optical fiber made of a material such as ZrF ₄ . Fluoride glass optical fibers have excellent transmission characteristics especially for light in the infrared region, and Pr
(Praseodymium) or Er (erbium) can be added to use as an optical fiber amplifier in the 1.3 μm band or the 1.5 μm band. Therefore, using this fluoride glass optical fiber, an optical amplification device, an optical transmission device, etc. Optical device is configured.

FIG. 4 is a block diagram showing a conventional optical amplifying device disclosed in, for example, Japanese Patent Application Laid-Open No. 6-53575, in which 1 is a Pr-doped fluoride glass optical fiber (Praseodymium-) having an optical amplifying action. Doped
Fluoride Fiber (hereinafter referred to as "PDFF") 1c is a hermetically sealed container for storing the PDFF 1, 1g
Is an inert gas such as nitrogen gas or argon gas filled in the closed container 1c, 2 and 3 are connecting portions between the PDFF 1 and the silica glass optical fiber 7, and 4 is a wavelength 1 for exciting Pr ions in the PDFF 1. An excitation light source that oscillates and supplies a laser beam of 0.02 μm, 4a is a power source line of the excitation light source 4, and 5 is a WDM (Wavelength Div) that joins the lights.
Ion Multiplexing) coupler 6 is an optical isolator for preventing oscillation and unstable operation inside the optical amplifier by allowing only one direction of light to pass through,
7 is a silica glass optical fiber.

It should be noted that PDFF made of ZrF ₄ system material
Since No. 1 is deliquescent, its properties deteriorate when exposed to moisture in the air, and further, failure due to breakage occurs. In order to prevent such performance deterioration due to deliquescence, the PDFF1 is housed in a closed container 1c filled with an inert gas 1g, and is shielded from moisture in the air. Further, as shown in FIG. 5, the excitation light source 4 is usually hermetically sealed in the container 4c to prevent deterioration of the semiconductor, and the WDM coupler 5 and the optical isolator 6 are also protected from damage due to external impact or the like. It is housed in containers 5c and 6c for prevention.

Next, the operation will be described. In the pumping light source 4, pumping light having a wavelength of 1.02 μm for pumping Pr ions in the PDFF 1 is generated, and this pumping light is made of the silica glass optical fiber 7, the WDM coupler 5, the silica glass optical fiber 7, and the connecting portion 2. And then enters the PDFF 1 to excite Pr ions in the PDFF 1.

The signal light having a wavelength of 1.3 μm is WDM
In the coupler 5, it is introduced into the silica glass optical fiber 7 directed to the PDFF 1, passes through the connecting portion 2, and enters the PDFF 1. The signal light having a wavelength of 1.3 μm that has entered the PDFF 1 is amplified by the stimulated emission of excited Pr ions while passing through the PDFF 1, and its power increases.

The amplified signal light having a wavelength of 1.3 μm passes through the connection part 3 on the output side, the silica glass optical fiber 7 and the optical isolator 6, and is output to the outside of the optical amplifier.

Here, the PDFF1 is deliquescent and is damaged when exposed to moisture, but since it is stored in a closed container 1c filled with 1 g of an inert gas, the PDFF1
Performance deterioration due to deliquescence of F1 is prevented.

[0009]

Since the conventional optical device using the fluoride glass optical fiber is configured as described above, the optical components such as the pumping light source 4, the WDM coupler 5, the optical isolator 6 are fluoride. Since the glass optical fiber is housed in a container different from the hermetically sealed container 1c, the number of parts is large, and the parts cost and the manufacturing cost are high.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to prevent performance deterioration and failure due to humidity with a simple structure with a small number of parts and to reliably continue operation. An object is to obtain an optical device using a fluoride glass optical fiber having high properties.

[0011]

An optical device according to the present invention is a fluoride glass optical fiber, one or a plurality of optical components connected to the fluoride glass optical fiber, and moisture from the inside. And an airtight container for housing the optical component together with the end of the fluoride glass optical fiber.

An optical device according to a second aspect of the present invention integrally houses the optical device in a hermetically sealed container.

An optical device according to a third aspect of the present invention is an optical device in which optical components are housed in two hermetically sealed containers which house both ends of a fluoride glass optical fiber.

An optical device according to a fourth aspect of the present invention is one in which an airtight container is filled with an inert gas.

An optical device according to a fifth aspect of the present invention is a sealed container filled with a liquid containing no water.

In the optical device according to the sixth aspect of the present invention, a hermetically sealed container is filled with matching oil having a refractive index close to that of the fluoride glass optical fiber.

According to the optical device of the seventh aspect of the present invention, the inside of the closed container is evacuated.

An optical device according to an eighth aspect of the present invention is a fluoride glass optical fiber, one or a plurality of optical components connected to the fluoride glass optical fiber, and the optical component being a fluoride glass optical fiber. And a resin mold for airtightly covering the end of the.

An optical device according to a ninth aspect of the present invention is an optical device integrally hermetically covered with a resin mold.

According to the tenth aspect of the invention, the optical device is hermetically coated with the two resin molds that hermetically coat both ends of the fluoride glass optical fiber.

In the optical device according to the eleventh aspect of the present invention, any one or a combination of an optical isolator, an optical multiplexer / demultiplexer, an optical filter, a quartz optical fiber, a semiconductor laser is used as an end of a fluoride glass optical fiber. It is housed together with the parts in an airtight container or airtightly covered with a resin mold.

The optical device according to the twelfth aspect of the present invention comprises a fluoride glass optical fiber containing at least ZrF ₄ , Ba.
F ₂ , LaF ₃ , AlF ₃ , NaF, InF ₃ , GaF
It is composed of a material containing any of the _three .

In the optical device according to the thirteenth aspect of the present invention, a rare earth element is added to at least the core portion of the fluoride glass optical fiber so as to have a light amplification effect.

An optical device according to a fourteenth aspect of the present invention uses Pr or Er as a rare earth element.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. 1 is a block diagram showing an optical amplifying device according to Embodiment 1 of the present invention. In the figure, 1 is Zr.
F ₄ , BaF ₂ , LaF ₃ , AlF ₃ , NaF, InF
Pr-doped fluoride glass optical fiber (PDF) in which Pr (praseodymium) is added to a fluoride glass optical fiber made of a material such as ₃ , GaF ₃
F), 2 and 3 are connection portions (end portions) of the PDFF 1 with the silica glass optical fiber 7. The format of the connection part is PD
There are cases where both cross sections of the FF1 and the silica glass optical fiber 7 are aligned with each other and are brought into contact with each other with an adhesive, or there is a case where they are only brought into contact with each other with their axes aligned.

Reference numeral 4 denotes an excitation light source (semiconductor laser, optical component) which oscillates and supplies a laser beam having a wavelength of 1.02 μm for exciting Pr ions in the PDFF 1, and 4 a denotes an excitation light source 4.
The power supply line 5 is a WDM coupler (optical multiplexer / demultiplexer, optical component) that joins the lights, and 6 is a light that prevents oscillation and unstable operation inside the optical amplifier by allowing only one direction of light to pass. The isolator (optical component) 7 is a quartz glass optical fiber (quartz optical fiber, optical component), and the above is the same as the conventional one shown in FIG.

Reference numeral 11 denotes a hermetically sealed container that integrally houses the PDFF 1, the pumping light source 4, the WDM coupler 5, the optical isolator 6, and the silica glass optical fiber 7 connecting these and the connecting portions 2 and 3 and is airtight. Metals with excellent corrosion resistance,
It is formed of a material such as plastic or ceramic. 11 g is nitrogen gas filled in the closed container 11,
It is an inert gas such as argon gas. A portion where the quartz glass optical fiber 7 and the power supply line 4a are exposed from the closed container 11 is hermetically sealed with an adhesive or the like.

Next, the operation will be described. In the pumping light source 4, pumping light having a wavelength of 1.02 μm for pumping Pr ions in the PDFF 1 is generated, and this pumping light is a quartz glass optical fiber 7, a WDM coupler 5, a quartz glass optical fiber 7, and a connecting portion 2. And then enters the PDFF 1 to excite Pr ions in the PDFF 1.

The signal light having a wavelength of 1.3 μm is WDM
In the coupler 5, it is introduced into the silica glass optical fiber 7 directed to the PDFF 1, passes through the connecting portion 2, and enters the PDFF 1. The signal light with a wavelength of 1.3 μm incident on the PDFF 1 is amplified by the stimulated emission of Pr ions excited while passing through the PDFF 1, and the power is increased.

The amplified signal light having a wavelength of 1.3 μm passes through the connection part 3 on the output side, the silica glass optical fiber 7 and the optical isolator 6, and is output to the outside of the optical amplifier.

The operation as the above-mentioned optical amplifier is the same as that of the conventional example. In addition, PDFF1 is inert gas 11g
Since it is located in the closed container 11 filled with, the performance deterioration due to the deliquescent of the PDFF 1 is prevented as in the conventional example.

In addition to this, in the first embodiment,
The closed container 11 filled with 11 g of inert gas is
F1, pump light source 4, WDM coupler 5, optical isolator 6, and silica glass optical fiber 7 for connecting them
And the connecting portions 2 and 3 are integrally housed, and the performance deterioration and failure of each optical component due to moisture or external impact can be prevented only by using one closed container 11 as a container. It is possible to reduce the number of points and suppress the component cost and the manufacturing cost.

Embodiment 2 FIG. In the first embodiment, the airtight container 11 is filled with the inert gas 11g, but it may be filled with air from which moisture is sufficiently removed, and the same effect as that of the first embodiment can be obtained.

Embodiment 3 In each of the above-described embodiments, an example in which the airtight container 11 is filled with gas has been described, but it may be filled with a liquid containing no water, and the same effects as those of the first and second embodiments are obtained. In this case, appropriate measures are taken, such as using a non-conductive liquid to prevent a short circuit in the excitation light source 4 or a non-oxidizing liquid to prevent corrosion.

Embodiment 4 FIG. As the water-free liquid of the third embodiment, matching oil whose refractive index is close to that of the PDFF 1 can be used. in this case,
In addition to the effects of each of the above-described embodiments, the connection portion 2,
In the case where connection is performed in a state where the fiber end faces on both sides are brought into contact with each other without interposing an adhesive or the like in 3, the minute space between the end faces of the PDFF 1 and the silica glass optical fiber 7 is filled with matching oil, Transmission loss due to reflection and refraction due to the difference in refractive index between the fluoride glass optical fiber and the space can be suppressed.

Embodiment 5 In each of the above-described embodiments, an example in which the airtight container 11 is filled with a gas or a liquid has been described, but the airtight inside of the airtight container 11 may be evacuated, and the same effect as that of each of the above-described embodiments is obtained. The degree of vacuum in the closed container 11 may be set so that the deliquescent of the PDFF 1 does not occur for a long period of time when the optical amplifier is used.

Embodiment 6 FIG. FIG. 2 is a configuration diagram showing an optical amplifying device according to a sixth embodiment of the present invention. In the figure, 12 is a resin mold made of a sealing resin such as an epoxy resin or a silicone resin for integrally airtightly covering the optical amplifying device. Is. The same parts as those shown in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted.

In the sixth embodiment, the heat sink 4 made of metal, ceramics or the like is arranged so that the heat generated by the excitation light source 4 is sufficiently radiated.
h is exposed on the surface of the resin mold 12.

In the sixth embodiment, similarly to the above-mentioned respective embodiments, it is possible to prevent performance deterioration or failure of each optical component due to moisture or external impact without using a large number of storage containers, and the number of components is increased. It is possible to reduce the component cost and the manufacturing cost, facilitate the transportation of the optical amplifier as an integrated unit, and facilitate the use in combination with other optical components. .

Embodiment 7 FIG. 3 is a configuration diagram showing an optical amplifying device according to a seventh embodiment of the present invention. In the figure, 13 is a hermetically sealed container for accommodating the connecting portion 2 together with the pumping light source 4 and the WDM coupler 5, and 14 is It is a closed container that houses the connection part 3 together with the optical isolator 6. Further, 13 g and 14 g are inert gases such as nitrogen gas and argon gas filled in the closed containers 13 and 14. In addition,
About the same thing as what was shown in FIG. 1, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

In each of the above-mentioned embodiments, as shown in FIGS. 1 and 2, an example in which the entire optical amplifying device is integrally housed in a closed container or a resin mold is shown. It has become possible to sufficiently prevent deliquescent by coating the side surface of the glass with polyimide or the like, and the end portion of the fluoride glass optical fiber may be housed in a closed container. In
The connection parts 2 and 3 in which the ends of the PDFF 1 are located are housed in a total of two hermetically sealed containers 13 and 14 together with the optical parts connected to the same, and are filled with inert gas 13g and 14g. As in the case of the first embodiment, it is possible to prevent performance deterioration or failure of each optical component due to moisture or external impact with a small number of storage containers, and it is possible to suppress component cost and manufacturing cost.

Even if the airtight containers 13 and 14 are filled with air or water-free liquid or matching oil from which moisture is sufficiently removed as in the second to sixth embodiments, a vacuum is drawn. Also, it may be molded instead of being housed in an airtight container, and the same effects as those of the above-described respective embodiments can be obtained. It is also possible to perform different treatments on both parts without taking the same moisture proof measure.

In each of the above embodiments, an example in which Pr is added to the fluoride glass optical fiber has been shown.
It goes without saying that the present invention is also applicable to a light amplification device in which another rare earth element such as Er (erbium) is added to a fluoride glass optical fiber.

Further, in each of the above-mentioned embodiments, the present invention is applied to the optical amplifying device in which the rare earth element is added to the fluoride glass optical fiber. However, for example, the fluoride is not added to the optical amplifier. Embodiment 7 can also be applied to an optical transmission device that uses a fluoride glass optical fiber as a transmission fiber for far infrared rays and transmits far infrared light via a fluoride glass optical fiber. The present invention can also be applied to other optical devices that use a fluoride glass optical fiber together with an optical component other than the optical components used above, such as an optical filter.

The present invention can be applied not only to the fluoride glass optical fiber but also to an optical device using another optical fiber which needs to block moisture.

[0046]

As described above, according to the first aspect of the present invention, in an optical device in which a fluoride glass optical fiber and one or more optical components are connected, the optical component is a fluoride glass optical fiber. Since the optical parts and the end portions of the fluoride glass optical fiber are housed in the same hermetically sealed container together with the end of the fiber and the moisture is removed from the hermetically sealed container, a small number of them are housed in the same hermetically sealed container. With the storage container, it is possible to prevent performance deterioration and failure of each optical component due to moisture and external impact, reduce the number of components, and reduce the component cost and the manufacturing cost.

According to the second aspect of the invention, since the optical device is integrally housed in the hermetically sealed container, only one hermetically sealed container is used as the housing container so as to prevent moisture and external shock of each optical component. It is possible to prevent the performance deterioration and the failure due to the above, reduce the number of parts, and suppress the parts cost and the manufacturing cost.

According to the third aspect of the invention, since the optical components are accommodated by the two hermetically sealed containers that accommodate both ends of the fluoride glass optical fiber, each optical component can be accommodated by a small number of containers. It is possible to prevent performance deterioration and failure due to moisture and external shock, and to reduce component cost and manufacturing cost.

According to the fourth aspect of the invention, since the airtight container is filled with the inert gas, the end portion of the fluoride glass optical fiber is isolated from the water, and the end portion of the fluoride glass optical fiber is isolated. There is an effect that it is possible to prevent performance deterioration due to deliquescence.

According to the fifth aspect of the invention, since the liquid containing no water is filled in the closed container,
There is an effect that performance deterioration due to deliquescence at the end of the fluoride glass optical fiber can be prevented.

According to the sixth aspect of the present invention, since the matching oil having a refractive index close to that of the fluoride glass optical fiber is filled in the airtight container, it is possible to use other matching materials for the fluoride glass optical fiber. When the fluoride glass optical fiber is directly contacted at the connection part with the optical device, the transmission loss due to reflection and refraction due to the difference in refractive index between the fluoride glass optical fiber and the minute space of the connection part is caused. There is an effect that can be suppressed.

According to the seventh aspect of the present invention, since the inside of the closed container is evacuated, there is an effect that performance deterioration due to deliquescent of the end portion of the fluoride glass optical fiber can be prevented.

According to the invention described in claim 8, the optical component is
Since it is configured to be airtightly covered with a resin mold together with the end of the fluoride glass optical fiber, it is possible to prevent performance deterioration or failure of each optical component due to moisture or external impact without using many storage containers as in the past. Therefore, the number of parts can be reduced, and the parts cost and the manufacturing cost can be suppressed.

According to the ninth aspect of the invention, since the optical device is integrally air-tightly covered with the resin mold, moisture and external impact of each optical component can be eliminated without using a large number of storage containers as in the conventional case. It is possible to prevent performance deterioration and failure due to the above, reduce the number of parts, reduce the parts cost and the manufacturing cost, and easily transport the optical device as an integrated unit. There is an effect that it can be easily used in combination with.

According to the tenth aspect of the invention, since the optical parts are hermetically covered by the two resin molds for hermetically covering both ends of the fluoride glass optical fiber, a large number of storage containers are used. It is possible to prevent performance deterioration and failure due to moisture and external shock of each optical component without
There is an effect that the number of parts can be reduced and the parts cost and the manufacturing cost can be suppressed.

According to the invention of claim 11, an optical isolator, an optical multiplexer / demultiplexer, an optical filter, a quartz optical fiber,
Either of the semiconductor lasers or a combination thereof,
Along with the end portion of the fluoride glass optical fiber, it is housed in a hermetically sealed container or airtightly covered with a resin mold, so that the optical device using each of the above components can be used for moisture or moisture of each optical component without using a large number of storage containers. It is possible to prevent performance deterioration and failure due to external impact, reduce the number of parts, and suppress parts cost and manufacturing cost.

According to the twelfth aspect of the present invention, at least ZrF ₄ , BaF ₂ , LaF ₃ , AlF ₃ , NaF,
InF _3, and then, it is applied to the above inventions to the optical device using a fluoride glass optical fiber comprising a material of any of _{GaF 3, ZrF 4, BaF 2} , LaF
There is an effect that it is possible to prevent performance deterioration due to deliquescence at the end of the fluoride glass optical fiber made of a material such as ₃ , AlF ₃ , NaF, InF ₃ , GaF ₃ .

According to the thirteenth aspect of the present invention, each of the above-mentioned inventions is applied to an optical device having a light amplifying effect by adding a rare earth element to at least the core portion of a fluoride glass optical fiber. Therefore, there is an effect that it is possible to obtain a highly reliable optical amplifying device capable of preventing performance deterioration and failure due to moisture and reliably continuing the operation with a simple configuration having a small number of parts.

According to the fourteenth aspect of the present invention, since each of the above inventions is applied to the optical device using the fluoride glass optical fiber to which Pr or Er is added as the rare earth element, the number of parts is small. With such a configuration, it is possible to obtain a highly reliable optical amplifier in the 1.3 μm band or 1.5 μm band, which is capable of preventing performance deterioration or failure due to moisture and reliably continuing operation.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an optical amplifier device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing an optical amplifying device according to a sixth embodiment of the present invention.

FIG. 3 is a configuration diagram showing an optical amplifier according to Embodiment 7 of the present invention.

FIG. 4 is a configuration diagram showing a conventional optical amplifier.

FIG. 5 is a configuration diagram showing a conventional optical amplifier.

[Explanation of symbols]

1 PDFF (fluoride glass optical fiber), 2, 3
Connection part (end part), 4 pumping light source (semiconductor laser, optical component), 5 WDM coupler (optical multiplexer / demultiplexer, optical component), 6
Optical isolator (optical component), 7 Quartz glass optical fiber (quartz optical fiber, optical component), 11, 13, 14 Airtight container, 11g, 13g, 14g Inert gas, 12
Resin mold.

Claims (14)

[Claims] 1. A fluoride glass optical fiber, one or more optical components connected to the fluoride glass optical fiber, and moisture removed from the inside of the optical component along with an end portion of the fluoride glass optical fiber. An optical device having a closed container for storing. 2. The optical device according to claim 1, wherein the hermetically sealed container integrally houses the optical device. 3. The optical device according to claim 1, wherein the optical parts are housed by two hermetically sealed containers which house both ends of the fluoride glass optical fiber. 4. The closed container is filled with an inert gas, as claimed in any one of claims 1 to 3.
The optical device according to the item. 5. The optical device according to claim 1, wherein the airtight container is filled with a liquid containing no water. 6. The optical device according to claim 5, wherein the liquid containing no water is a matching oil having a refractive index close to that of the fluoride glass optical fiber. 7. The optical device according to claim 1, wherein the closed container is evacuated. 8. A fluoride glass optical fiber, one or a plurality of optical components connected to the fluoride glass optical fiber, and a resin mold that hermetically coats the optical component together with an end portion of the fluoride glass optical fiber. Optical device equipped with. 9. The optical device according to claim 8, wherein the optical device is integrally airtightly covered with a resin mold. 10. The optical device according to claim 8, wherein the optical component is hermetically coated with two resin molds that hermetically coat both ends of the fluoride glass optical fiber. 11. An optical component housed in a hermetically sealed container or hermetically covered with a resin mold is any one of an optical isolator, an optical multiplexer / demultiplexer, an optical filter, a quartz optical fiber, and a semiconductor laser, or a combination thereof. The optical device according to any one of claims 1 to 10, wherein: 12. The material of the fluoride glass optical fiber comprises:
At least ZrF ₄ , BaF ₂ , LaF ₃ , AlF ₃ ,
The optical device according to any one of claims 1 to 11, comprising any one of NaF, InF ₃ , and GaF ₃ . 13. The fluoride glass optical fiber according to claim 1, wherein at least a core portion of the fluoride glass optical fiber is doped with a rare earth element and has a light amplifying action. The optical device described. 14. The optical device according to claim 13, wherein the rare earth element is Pr or Er.