JP4632227B2 - Optical module - Google Patents

Description

  The present invention relates to, for example, an optical module used in an optical add / drop device that branches signal light from a trunk line toward a relay station or inserts signal light from a relay station into the trunk line in the optical communication field.

  Patent Document 1 discloses an apparatus used for the purpose of branching a signal of a specific wavelength to a relay station or inserting a signal of a specific wavelength from a relay station in optical communication using wavelength division multiplexing. An optical add / drop multiplexer is known.

  As shown in FIG. 3, this optical add / drop device includes an optical demultiplexer 3 that demultiplexes wavelength multiplexed light input from the input optical transmission line 1 into light of each wavelength, and each wavelength once demultiplexed. And an optical multiplexer 4 for multiplexing and transmitting the light to the output transmission path 2. The optical add / drop device also splits the light of each wavelength demultiplexed by the optical demultiplexer 3 to the receiver 7 of the relay station 8 and then transmits the signal transmitted from the transmitter 6 of the relay station 8. An optical switch 5 for selecting whether to insert a new light or to transmit the light of each wavelength demultiplexed by the optical demultiplexer 3 as it is to the optical multiplexer 4 corresponds to the optical path of each wavelength. There are several.

  In such an add / drop device, the optical demultiplexer 3 or the optical multiplexer 4 has a function of fixing a wavelength selection filter, a lens or the like on an optical path from the optical fiber and separating a single wavelength component from the multi-wavelength signal. Alternatively, a filter module having a function of inserting a single wavelength component into a multi-wavelength signal is often used.

  For example, as described in Patent Document 2 and Patent Document 3, such a filter module has a configuration in which a collimator formed of a lens and an optical fiber is arranged to face each other with a wavelength selection filter interposed therebetween. .

  In general, in such a filter module, a wavelength selection filter, a lens, and an optical fiber are inserted and fixed in a common cylindrical casing with the optical axis adjusted. Such a module is generally called an Add / Drop Multiplexer (ADM).

  Since the optical demultiplexer 3 and the optical multiplexer 4 in the optical add / drop device of FIG. 3 need to perform similar multiplexing or demultiplexing for a plurality of wavelengths, a plurality of the above filter modules having different wavelength separation characteristics are provided. These are used by sequentially connecting these optical fibers at the signal input / output ends by a method such as fusion. Such a module is generally called “Mux / DeMux”. The light input to the optical demultiplexer 3 or the optical multiplexer 4 is demultiplexed to each wavelength by sequentially passing through a plurality of the filter modules, or the light of each wavelength is sequentially multiplexed. (For example, refer patent document 4 etc.). Note that the plurality of unit modules connected in sequence are generally mounted in a single case.

JP 2000-183816 A Japanese National Patent Publication No. 10-511476 Japanese Patent Laid-Open No. 10-311905 JP 11-337765 A

  By the way, in the optical add / drop multiplexer using the above-described filter module, it is necessary to increase the number of used single filter modules correspondingly as the number of channels used for optical communication increases. Therefore, the raw material parts price is more than a multiple of the price of a single filter module. In addition, since the optical fiber at the input / output end of the filter module is fused, the process is complicated and expensive, and connection loss due to misalignment at the time of fusion splicing occurs. Furthermore, since the single filter module has a structure fixed in the casing, it requires a wasteful volume other than the functional part, and the necessary part volume increases as the number of channels increases. was there.

  In order to solve these problems, the present inventors have eliminated the exterior body that is the housing of the filter module, fixed each component as described above on a single substrate, and light propagated in space between the components. We tried to reduce the cost, size, and loss of optical modules with the minimum necessary volume without using unnecessary parts.

  However, when the component parts in the module are actually separated and arranged on the substrate, the optical axis shift occurs in the light emitted from each component, optical coupling cannot be performed easily, and the expected performance cannot be obtained. It turned out that.

As a factor of this optical axis deviation,
(1) In order to reduce reflection loss, the end surfaces of the optical fiber and the gradient index lens are inclined end surfaces;
(2) The optical axis is shifted when light passes through the substrate of the dielectric multilayer filter that is the wavelength selection filter;
(3) The external accuracy of each component can be produced only below the processing accuracy required for optical coupling between single mode fibers;
(4) The processing accuracy of the substrate on which these components are installed can be made only below the accuracy required for optical coupling between single mode fibers;
And so on.

  Specifically, the optical coupling between the optical fibers, particularly between the single mode fibers, requires a core diameter of 10 μm or less, so that submicron level alignment accuracy is required. With passive optical components such as lenses and lenses, component tolerances and manufacturing tolerances exceed this, and fabrication with this accuracy is virtually impossible. Even if individual fabrication is possible, a problem still remains in the collimator fabricated by the current mainstream manufacturing method in which the emitted light deviates from the optical axis.

  FIG. 4 shows a current mainstream manufacturing method, that is, a collimator manufactured by a combination of the fiber pigtail 11 and the gradient index lens 12. In order to reduce the reflection loss, each end face of the pigtail 11 and the lens 12 is provided with an angle of about 8 °, and this causes the outgoing light to have an angular deviation δ and an angular deviation relative to the position of the incident light. θ is generated. In particular, the amount of optical axis deviation due to the angle deviation θ increases as the coupling distance L increases as shown in FIG. Therefore, when the distance between the collimator pair installed in the V-groove etc. on the same straight line is several mm or more, the optical coupling becomes almost 0 (zero).

  In addition, when the V groove for fixing the collimator on the substrate is manufactured by grinding, it is desirable that the two V grooves for arranging the collimator pair are formed in parallel with each other because of work requirements. On the groove, a collimator pair that realizes effective optical coupling cannot be produced for the reason described above.

  In addition, as shown in FIG. 6, an interference filter such as a wavelength selection filter is usually formed by forming a film on a glass substrate 15 having a finite thickness, in order to avoid damage to the generated film pressure. It has a thickness of about 1 mm. A parallel displacement amount δ of light incident at an incident angle θ from a medium 1 having a refractive index n1 to a medium 2 having a refractive index n2 having a thickness h (= difference between an optical path to be passed when there is no medium 2 and an actual optical path) Can be expressed as:

  FIG. 7 shows the difference between the optical axis deviation δ (μm) and the incident angle θ (Degree) when light passes through a substrate having various thicknesses (0.5 to 1.5 mm) as shown in FIG. Showing the relationship. As shown in this figure, since the optical axis shift occurs depending on the thickness and incident angle of the substrate, the filter is inserted even if the optical coupling of the collimator pair is performed in advance before the interference filter is inserted. By doing so, the optical path is shifted, and the loss is greatly increased or cannot be coupled.

  Furthermore, even when designing with all of the above-mentioned deviations in mind, processing errors and assembly errors such as parts and boards will occur in each part, and these errors are the accuracy required for optical coupling. Because it is a level that clearly deviates from, it becomes meaningless.

  As described above, in reality, if the components are simply arranged in parallel in the V-grooves for fixing the components formed on the same substrate as in the conventional trial, the optical axis deviation is practically large. There was a problem that sufficient optical coupling could not be obtained.

  The present invention has been made to solve the above-described problems. In an optical module in which components such as a collimator and an interference filter are arranged on the same substrate, an optical axis shift can be easily corrected. An object of the present invention is to provide an optical module capable of obtaining good optical coupling. It is another object of the present invention to provide an optical module that can be used as an optical demultiplexing device or an optical multiplexing device used in the field of optical communication, and that can be reduced in size and price with low loss.

An optical module according to a first aspect of the present invention includes an input light collimator that collimates input light from the outside, an output light collimator that inputs the output light to the outside, collects the light, and transmits the light to the outside. An interference filter disposed in the optical path from the collimator to the collimator for output light and an optical path correction member disposed in the optical path between each collimator and the interference filter are provided on a common substrate. And each of the collimators is disposed in a V-groove formed in parallel on the common substrate .

In the present invention, since the optical path correction member is disposed in the optical path between each collimator and the interference filter, the optical axis deviation between the collimators can be easily corrected by adjusting each optical path correction member. And good optical coupling can be realized. In addition, each component is fixed on a common board, and light is propagated between the components. This eliminates the use of unnecessary components, reduces the cost and size of the optical module with the minimum required volume. Can be achieved. In the present invention, each collimator is fixed to a V-groove formed in parallel on the common substrate. Therefore, by adjusting the optical path with the optical path correcting member, the parallel V-groove that is easy to process is used. The optical axis shift between the collimators can be easily corrected, and good optical coupling can be performed.

As the interference filter, as in the invention of claim 2,
(A) a wavelength selection filter that transmits only light in a specific wavelength band among incident light and reflects light of other wavelengths;
(B) a gain equalization filter that corrects the light intensity so as to flatten the intensity when the intensity of the incident light is not uniform with respect to the wavelength;
(C) a filter for extracting only a part of the amount of incident light;
At least one of the above can be used.

An optical module according to a third aspect of the invention includes an input light collimator that collimates wavelength multiplexed light transmitted from an input optical transmission line into parallel light, and a wavelength multiplexed light that is incident through the input light collimator. A wavelength selection filter that transmits only light in the wavelength band and reflects light in other wavelength bands, and a collimator for branching light that collects the light that has passed through the wavelength selection filter and transmits it to an external branching optical transmission line A collimator for inserting light that collimates light of a specific wavelength band transmitted from an external optical transmission path for insertion into parallel light and enters the wavelength selection filter, and enters the wavelength selection filter by the collimator for insertion light. The output light collimator that collects and transmits the combined light of the transmitted light and the light reflected by the wavelength selection filter of the wavelength multiplexed light to an external output optical transmission line; Serial and an optical path correction member which is arranged in the optical path between the collimator and the wavelength selective filter, Ri Na equipped with a respective collimator and the wavelength selective filter and the light path correction element on a common substrate, And each said collimator is arrange | positioned to the V groove formed in parallel on the said common board | substrate, It is characterized by the above-mentioned.

  In the present invention, since the optical path correction member is arranged in the optical path between each collimator and the wavelength selection filter, the optical axis deviation between the collimators can be easily corrected by adjusting each optical path correction member. And good optical coupling can be performed. Therefore, a low-loss optical add / drop multiplexer can be realized. In addition, each component is fixed on a single substrate and light is propagated between the components, eliminating the need for wasted components, reducing the cost of optical modules and reducing the volume required. Miniaturization can be achieved.

The optical module of the invention of claim 4 includes a demultiplexing function that transmits only light of a specific wavelength in incident light and reflects light of other wavelengths, and light of a specific wavelength that is incident and transmitted from one side. Equipped with a plurality of wavelength selection filters having a multiplexing function for multiplexing light of other wavelengths that are incident and reflected, with different specific wavelengths,
The plurality of wavelength selection filters are arranged so that the reflected light of the filters enters in order from the upstream side to the downstream side in the light traveling direction,
Collimators are arranged on the optical path of the incident light to the most upstream wavelength selective filter, on the optical path of the transmitted light of each wavelength selective filter, and on the optical path of the reflected light of the downstream downstream wavelength selective filter,
An optical path correction member is arranged in the optical path between each collimator and the wavelength selection filter,
Each of the collimators, the wavelength selection filter, and the optical path correcting member is disposed on a common substrate , and each of the collimators is disposed in a V groove formed in parallel on the common substrate. .

  In the present invention, light of different wavelengths can be branched and extracted sequentially from the wavelength multiplexed light, or light of different wavelengths can be sequentially multiplexed and wavelength multiplexed. At that time, the collimator and wavelength selection filter are fixed on a single substrate, and light is propagated spatially between components, so there is no need to use unnecessary components, and the optical module can be reduced in the minimum volume. Price and size can be reduced. Further, since the optical path correction member is disposed in the optical path between each collimator and the wavelength selection filter, the optical axis deviation between the collimators can be easily corrected by adjusting each optical path correction member. And good optical coupling can be performed. Therefore, a low-loss multi-wavelength optical demultiplexing device or multi-wavelength optical multiplexing device can be made.

  The optical module according to a fifth aspect of the present invention is the optical module according to the fourth aspect, wherein the most upstream collimator is an input light collimator that receives wavelength multiplexed light from an external input optical transmission line, and the others. The collimator is used as a branching light collimator for taking out the light transmitted or reflected by the wavelength selection filter to the outside, and the wavelength selective filter is used as a demultiplexing optical element to sequentially demultiplex wavelength multiplexed light. A multi-wavelength optical demultiplexing device is configured.

  An optical module according to a sixth aspect of the present invention is the optical module according to the fourth aspect, wherein the most downstream collimator is an output light collimator that transmits output light to an external output optical transmission line, and the other collimators. Is a collimator for insertion light that makes light of different wavelengths incident on the wavelength selection filter from the outside, and a plurality of light beams of different wavelengths are sequentially multiplexed by using the wavelength selection filter as a multiplexing optical element. A wavelength optical multiplexer is configured.

  According to the invention of claim 5, it is possible to sequentially demultiplex wavelength-division multiplexed light into light of different wavelengths with low loss. According to invention of claim 6, light of different wavelengths with low loss is multiplexed. Wavelength multiplexing can be performed.

A seventh aspect of the invention is characterized in that, in the first to sixth aspects of the invention, the collimator comprises an optical fiber and a collimator lens disposed at the exit end or the entrance end of the optical fiber .

According to an eighth aspect of the present invention, in the optical module according to any one of the first to sixth aspects, a mirror and / or a prism can be used favorably as the optical path correcting member. Here, as the prism, a total reflection prism, a wedge prism, or a total reflection prism that adjusts the position of a gimbal type is used.

As the prism used for the optical path correcting member according to the eighth aspect , it is further desirable to use the apex portion of a total reflection prism or a wedge-shaped prism having an arbitrary angle.

As described in claim 9 , it is more desirable to use a gimbal type mirror as the mirror used in the optical path correcting member described in claim 8 .

As described in claim 10 , it is more desirable to use a total reflection prism that adjusts the position of the gimbal type as the prism used in the optical path correction member described in claim 8 .

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram illustrating an optical module 100 according to a first embodiment of the present invention, in which (a) is a plan view and (b) is a side view. This optical module 100 functions as an optical add / drop device (that is, it splits light of a specific wavelength with respect to input wavelength multiplexed light to the outside and does not split light of a specific wavelength input from the outside. And four collimators 111, 112, 113, 114 and one wavelength selection filter 115 are arranged on the same substrate 130, and each wavelength selection filter 115 and each wavelength Mirrors 121, 122, 123, and 124 are disposed as optical path correction members between the collimators 111, 112, 113, and 114, respectively, so that the light propagates in space between the components.

  The wavelength selection filter 115 is a demultiplexing function that transmits only light of a specific wavelength in incident light and reflects light of other wavelengths, and light of a specific wavelength that is incident and transmitted from one side and is reflected from the other side. And a multiplexing function for multiplexing light of other wavelengths. The wavelength selective filter 115 is formed by forming an optical multilayer film (eg, dielectric multilayer film) on a light-transmitting substrate such as glass or resin so that filter characteristics can be exhibited by the material and layer structure of the optical multilayer film. Is. The optical multilayer film generally has a structure in which materials having a low refractive index and materials having a high refractive index are alternately stacked.

  In the optical module 100, an input light collimator 111, an output light collimator 112, a branch light collimator 113, and an insertion light collimator 114 are provided as four collimators.

  The input light collimator 111 collimates wavelength multiplexed light (input light) input from an input optical transmission path (trunk optical fiber) for spatial transmission and enters the surface of the wavelength selection filter 115, for branched light The collimator 113 collects light having a specific wavelength that is incident on and transmitted through the surface of the wavelength selection filter 115 and enters it into the branching optical transmission line, and the insertion light collimator 134 passes through an external insertion optical transmission line. The output light collimator 112 that collimates the incident light for spatial transmission and enters the back surface of the wavelength selection filter 115, the output light collimator 112 is light having a specific wavelength input from the outside to the wavelength selection filter 115 through the insertion light collimator 114. Then, the combined light of the other wavelengths reflected by the wavelength selection filter 115 is collected and output to the output optical transmission line.

  Each of the collimator 111 for input light, the collimator for output light 112, the collimator for branched light 113, and the collimator for inserted light 114 used in this embodiment is composed of a collimator lens that is optically coupled to an optical fiber. In addition, it performs the function of converting (collimating) the signal light of the optical fiber into collimated light and emitting it toward the space, or condensing and entering the parallel light that has been spatially transmitted onto the end face of the optical fiber.

  As the collimating lens, it is preferable to use a rod-shaped lens because it is easy to handle. Examples of such rod-shaped lenses include a gradient index rod-shaped lens and a lens in which a spherical or aspherical surface is formed at one end of a uniform rod. The collimator may be configured by arranging the optical fiber and the lens on the substrate, respectively, but a combination of the optical fiber and the lens may be prepared in advance, and this may be arranged on the substrate. . In the latter case, for example, the optical fiber is fixed to a holder having the same diameter as the collimator lens, and the collimator lens and the holder with the optical fiber are inserted and fixed to a common cylindrical member made of metal such as glass or stainless steel. Can be formed.

  The collimators 111 to 114 are respectively positioned and fixed on V grooves 131 to 134 formed in parallel with each other on the same substrate 130. Here, the first V-groove 131 to which the input light collimator 111 is fixed and the fourth V-groove 134 to which the insertion light collimator 114 is fixed are formed by cutting, and the second V-groove 112 to which the output light collimator 112 is fixed is formed. The V-groove 132 and the third V-groove 133 to which the branched light collimator 113 is fixed are formed by cutting.

  Accordingly, the input light collimator 111 and the output light collimator 112 are arranged adjacent to each other at a position close to one side of the rectangular substrate 130, and the branch light collimator 113 and The insertion light collimators 114 are arranged adjacent to each other. Further, since the first V-groove 131 and the fourth V-groove 134 are formed by being cut through, the output ends of the input light collimator 111 and the insertion light collimator 114 are opposed to each other, and the output light collimator 112. And the incident ends of the collimator 113 for branch light are opposed to each other. The wavelength selection filter 115 is disposed substantially at the center of the substrate 130 so as to be sandwiched between the two pairs of collimators 111, 114, 112, 113 facing each other.

  Then, the light emitted from the input light collimator 111 is incident on the surface (one surface) of the wavelength selection filter 115 at a predetermined angle, and the light transmitted through the wavelength selection filter 115 is incident on the branch light collimator 113. Optical path correction mirrors 121 and 123 are disposed on the optical path between the collimator 111 for wavelength 111 and the wavelength selection filter 115 and on the optical path between the collimator 113 for branched light and the wavelength selection filter 115, respectively. In addition, the light emitted from the insertion light collimator 114 is incident on the back surface (other surface) of the wavelength selection filter 115 at a predetermined angle, the light emitted from the insertion light collimator 114 and transmitted through the wavelength selection filter 115, and the input light. The optical path between the insertion light collimator 114 and the wavelength selection filter 115 and the output so that the combined light of the light emitted from the collimator 111 and reflected by the surface of the wavelength selection filter 115 enters the output light collimator 112. On the optical path between the light collimator 112 and the wavelength selection filter 115, optical path correction mirrors 124 and 122 are arranged, respectively.

  Here, as a substrate 130 used for fixing each of the collimators 111 to 114, the wavelength selection filter 115, and the like, a silicon substrate, a glass substrate, aluminum, or the like having a small thermal expansion coefficient is used in order to prevent displacement between components after assembly. A metal substrate, a plastic substrate, etc. can be used. Moreover, the thickness of the board | substrate 130 should just be a grade from which sufficient rigidity is acquired. Further, the V grooves 131 to 134 for collimator arrangement formed on the substrate 130 can be formed by grinding. When a glass or plastic substrate is used, the V groove can be formed by transferring the shape of the mold by press molding. Moreover, you may provide grooves, such as a wavelength selection filter and a slit which fixes a mirror, in a board | substrate.

  The mirrors 121 to 124 are used for changing the optical path and correcting the optical axis deviation caused by the external accuracy of the parts and the optical axis deviation when passing the parts. Therefore, it is preferable to use a mirror having a gimbal mechanism or a mirror having an adjustment mechanism equivalent thereto. A mirror having a gimbal mechanism refers to a mirror whose tilt can be adjusted around one point (normal center) of the mirror. As these mirrors 121-124, it is suitable to use metal mirrors, such as aluminum and gold | metal | money, from the point which is excellent in the reflectance and durability.

The optical module 100 can be manufactured as follows.
First, the substrate 130 on which the V grooves 131 to 134 are formed is prepared. Next, the collimators 111 to 114 are arranged and fixed in the V grooves 131 to 134 on the substrate 130. At this time, the collimators 111 to 114 may be fixed temporarily or permanently. However, in order to shorten the curing process time, such as heat curing or UV curing, it is preferable to bond them to the substrate all at once later.

After the collimators 111 to 114 are arranged, light is emitted from the input light collimator 111 on a trial basis, and the two mirrors 121 are provided between the collimators 111 and 113 so that the light is coupled to the branched light collimator 113. , 123 are arranged and the position and inclination thereof are adjusted. Since these two mirrors 121 and 123 have a function of performing three-dimensional optical path conversion by adjusting their orientation and inclination, the branched light collimator 113 converts the outgoing light from the input light collimator 111. It can be incident on any positional relationship, and optical coupling between the two can be performed with low loss. In order to confirm the optical coupling between the pair of collimators 111 and 113, a light source that generates light of an arbitrary wavelength and the collimator 111 on the emission side are connected, and the collimated light source light amount and the light amount incident on the counterpart collimator 113 are Monitor with an optical multimeter.
Similarly, mirrors 124 and 122 are disposed between the two collimators 114 and 112 so that light is emitted from the insertion light collimator 114 and appropriate light coupling is performed between the collimator 112 and the output light. And adjust the tilt.

  Next, the wavelength selection filter 115 is disposed in the approximate center of the substrate 130. This wavelength selection filter 115 can change its direction and inclination in the same manner as the mirrors 121 to 124. Here, first, light having a wavelength reflected by the wavelength selection filter 115 is emitted from the input light collimator 111. Then, the light emitted from the input light collimator 111 is reflected by the mirror 121 and enters the wavelength selection filter 115, and the light reflected by the wavelength selection filter 115 is further reflected by the mirror 122 and output light collimator 112. The position and inclination of the wavelength selection filter 115 are adjusted so as to be incident on.

  Next, light having a transmission wavelength of the wavelength selection filter 115 is emitted from the input light collimator 111. Then, the optical axis shift caused by passing through the wavelength selection filter 115 is adjusted by a mirror 123 disposed between the wavelength selection filter 115 and the branched light collimator 113. Further, the insertion light collimator 114 and the wavelength are emitted so that the light having the transmission wavelength of the wavelength selection filter 115 is emitted from the insertion light collimator 114 and the light transmitted through the wavelength selection filter 115 is optically coupled to the output light collimator 112. Adjustment is performed by a mirror 124 disposed between the selection filters 115.

  By adjusting the mirrors 121 to 124 as described above, the optical paths between all the components can be matched, and the light demultiplexing / multiplexing function (= optical branching) according to the wavelength selection characteristics of the wavelength selection filter 115 can be achieved. An optical module 100 having an insertion function) can be manufactured. According to the actually produced optical module 100, it was possible to perform optical coupling between each collimator pair with a coupling loss within 0.2 dB. In addition, it is preferable to fix each component arrange | positioned on the board | substrate 130 on the board | substrate 130 after an optical axis adjustment. However, as long as the mirrors 121 to 124 do not move during normal use, the inclination of the mirrors 121 to 124 may not be fixed and may be finely adjusted later. For example, it is also preferable to use a gimbal type mirror.

Next, the operation of the optical module 100 configured as described above will be described.
First, wavelength-division multiplexed light (including light having wavelengths λ1 to λn) supplied from the input optical transmission line is emitted as parallel light from the input light collimator 111. The emitted wavelength multiplexed light is incident on the surface side of the wavelength selection filter 115 via the mirror 121, and only the light of a specific wavelength (assuming that the wavelength is λ1) is only the wavelength selection filter due to the wavelength selectivity of the wavelength selection filter 115. Light having other wavelengths (wavelengths λ2 to λn) is reflected by the wavelength selection filter 115.

  The light of wavelength λ 1 that has passed through the wavelength selection filter 115 enters the branch light collimator 113 via the mirror 123 and is sent to the outside. On the other hand, the light of wavelength λ1 input from the outside is emitted as parallel light from the insertion light collimator 114. The light emitted from the insertion light collimator 114 is incident on the back side of the wavelength selection filter 115 via the mirror 124, passes through this, and combines with the light of wavelengths λ 2 to λn reflected by the wavelength selection filter 115. Then, the light becomes a wavelength multiplexed light including wavelengths λ1 to λn, enters the output light collimator 112 via the mirror 122, and is sent to the output optical transmission line. In this way, signal light having a specific wavelength is branched / inserted to the input wavelength multiplexed light.

  According to the optical module 100, since the collimators 111 to 114 are used for the light input / output portions so that the light is spatially propagated between the components, there is no need to connect the components with an optical fiber. In addition to facilitating and downsizing of the apparatus, it is possible to easily replace parts when a failure occurs. Further, since only one wavelength selection filter 115 is used for the one-wavelength add / drop processing, the number of expensive filters can be reduced, and the manufacturing cost can be reduced.

  Further, since the optical axis shift between the collimators 111 and 113 and between the collimators 114 and 112 is corrected by the mirrors 121 to 124 disposed between the wavelength selection filter 115 and the collimators 111 to 114, the mirrors 121 to 124 are corrected. By adjusting, sufficient optical coupling can be obtained, and optical add / drop processing with little loss can be performed. In addition, the collimators 111 to 114, the wavelength selection filter 115, and the mirrors 121 to 124 are arranged on the same substrate 130 so that light is spatially propagated between the components. The volume of the optical module 100 can be reduced in price and size. In particular, since the collimators 111 to 114 are fixed on the V grooves 131 to 134 formed on the substrate 130 and parallel to each other, the assembly can be easily performed.

  In the above embodiment, the case where the wavelength selection filter 115 is used as the interference filter is shown. However, in addition to this, a gain for flattening the light intensity when the light intensity of the original signal is not uniform with respect to the wavelength, etc. An interference filter having other filter characteristics, such as a filter for extracting a part of the amount of incident light, or a filter for extracting only a part of the amount of incident light may be used.

Next, a second embodiment of the present invention will be described.
FIG. 2 is a plan view showing an optical module 200 according to the second embodiment of the present invention. (A) indicates the light incident / exit direction when used as an optical demultiplexing device, and (b) indicates the light incident / exit direction when used as an optical multiplexing device by an arrow.

  In the optical module 200, a plurality of collimators 210 to 215, a plurality of wavelength selection filters 115a to 115d, and a plurality of mirrors 220 to 225 as optical path correction members are arranged and fixed on a common substrate 230. It is a thing. Each of these elements has the same function as that described in the first embodiment. For example, the wavelength selection filters 115a to 115d have a demultiplexing function that transmits only light of a specific wavelength in incident light and reflects light of other wavelengths, and light of a specific wavelength that is incident and transmitted from one side. And a multiplexing function for multiplexing light of other wavelengths incident and reflected.

  Here, a plurality of wavelength selection filters 115a to 115d having different specific wavelengths are provided. The first wavelength selection filter 115a has a characteristic of transmitting light of a specific wavelength λ1, the second wavelength selection filter 115b has a characteristic of transmitting light of a specific wavelength λ2, and the third wavelength selection filter 115c is The fourth wavelength selection filter 115d has a characteristic of transmitting light of the specific wavelength λ4. The fourth wavelength selection filter 115d has a characteristic of transmitting light of the specific wavelength λ4.

  The plurality of wavelength selection filters 115a to 115d are arranged so that the reflected light of the filters enters in order from the upstream side to the downstream side in the light traveling direction. Based on the case of using the optical demultiplexing device of (a) as a reference, the wavelength selection filters 115a to 115d are configured so that the reflected light of the filter enters in order from the upstream side to the downstream side in the light traveling direction. Arranged in this order. That is, the first and third wavelength selection filters 115a and 115c and the second and fourth wavelength selection filters 115b and 115d are in a diagonally opposed relationship, and the first and third wavelength selection filters 115a and 115c. The filters are arranged so that the second and fourth wavelength selection filters 115b and 115d are adjacent to each other.

  Then, an input / output collimator 210 is arranged on the optical path of the incident light to the most upstream wavelength selection filter 115a, and on the optical path of the transmitted light of each of the wavelength selection filters 115a to 115d and of the most downstream wavelength selection filter 115d. First to fifth collimators 211 to 215 for branch insertion are respectively arranged on the optical path of the reflected light, and further, optical path correction mirrors are provided on the optical paths between the collimators 210 to 215 and the wavelength selection filters 115a to 115d, respectively. 220 to 225 are arranged. The input / output collimator 210 and the second and fourth collimators 212 and 214 are arranged in this order along one short side of the rectangular substrate 230, and the first, third, and fifth collimators 211 and 213 are arranged. 215 are arranged in this order along the other short side of the substrate 230.

  Each mirror 221 to 216 adjusts the optical path so that light travels as follows. First, light emitted from the input / output collimator 211 is incident on the first wavelength selection filter 115a, and the transmitted light is incident on the first add / drop collimator 212. The reflected light of the first wavelength selection filter 115a is incident on the second wavelength selection filter 115b, and the transmitted light is incident on the second collimator 213 for branch insertion. The reflected light of the second wavelength selection filter 115b is incident on the third wavelength selection filter 115c, and the transmitted light is incident on the third collimator 214 for branch insertion. The reflected light of the third wavelength selection filter 115c enters the fourth wavelength selection filter 115d, and the transmitted light enters the fourth collimator 215 for branch insertion. The reflected light of the fourth wavelength selection filter 115d enters the fifth branch insertion collimator 216.

The optical module 200 can be manufactured as follows.
First, a substrate 230 having a V groove (not shown) is prepared. Next, each of the collimators 210 to 215 is disposed and fixed in a V groove on the substrate 230. Work for fixing and confirmation of optical coupling are the same as in the first embodiment.

  Next, light of an arbitrary wavelength is emitted from the input / output collimator 210, and the two mirrors 220 between the two collimators 210, 211 are coupled so that this light is coupled to the first branch insertion collimator 211. 221 are arranged and their position, orientation and inclination are adjusted. The two mirrors 220 and 221 installed between the collimators 210 and 211 have a function of performing three-dimensional optical path conversion by adjusting the direction and inclination thereof. Even in the positional relationship, optical coupling between the two can be performed with low loss.

  Next, the first wavelength selection filter 115a is disposed between the two mirrors 220 and 221 at a position where the light emitted from the input / output collimator 210 is incident. The first wavelength selection filter 115a has a function capable of changing its direction and inclination, like the mirrors 220 and 221. Further, the mirror 222 is installed so that the light emitted from the input / output collimator 210 and reflected by the first wavelength selection filter 115a enters the second add / drop collimator 212. That is, light having a wavelength (wavelength other than λ1) reflected by the first wavelength selection filter 115a is emitted from the input / output collimator 210, and this light is appropriately incident on the second add / drop collimator 212. As described above, the position, orientation, and inclination of the first wavelength selection filter 115a and the mirror 222 are adjusted.

  Here, by inserting the first wavelength selection filter 115a, the optical axis of incidence on the first add / drop collimator 211 is deviated. This will later be changed from the input / output collimator 210 to the first wavelength selection filter. By finely adjusting the direction and inclination of the mirror 221 so that the light having a transmission wavelength (λ1) of 115a is emitted and the light transmitted through the filter 115a is appropriately incident on the first branching / inserting collimator 211. Can be easily corrected. Therefore, optical coupling equivalent to that before insertion of the filter can be obtained.

Next, the second wavelength selection filter 115b is disposed between the first wavelength selection filter 115a and the mirror 222 at a position where the emitted light from the input / output collimator 210 (reflected light of the wavelength selection filter 115a) hits. The second wavelength selection filter 115b also has a function capable of changing its own direction and inclination like the mirror. Further, the mirror 223 is installed so that the light emitted from the input / output collimator 210 and sequentially reflected by the first and second wavelength selection filters 115a and 115b enters the third add / drop collimator 213. . That is, light of a wavelength (wavelength other than λ1 and λ2) reflected by the first and second wavelength selection filters 115a and 115b is emitted from the input / output collimator 210, and this light is used for the third branch insertion. The position / orientation / tilt of the second wavelength selection filter 115b and the mirror 223 are adjusted so as to properly enter the collimator 213.

  In this case as well, the optical axis incident on the second add / drop collimator 212 is shifted by inserting the second wavelength selection filter 115b. The direction and inclination of the mirror 222 are finely adjusted so that the light having the transmission wavelength (λ2) of the filter 115b is emitted and the light transmitted through the filter 115b is appropriately incident on the second add-and-drop collimator 212. Thus, it can be easily corrected. Therefore, optical coupling equivalent to that before insertion of the filter can be obtained.

  Next, the third wavelength selection filter 115c is arranged between the second wavelength selection filter 115b and the mirror 223 at a position where the light emitted from the input / output collimator 210 (reflected light of the wavelength selection filters 115a and 115b) hits. To do. The third wavelength selection filter 115c also has a function capable of changing its own direction and inclination like the mirror. In addition, light that is emitted from the input / output collimator 210 and sequentially reflected by the first, second, and third wavelength selection filters 115a, 115b, and 115c enters the fourth add / drop collimator 214. A mirror 224 is installed. That is, light having a wavelength (wavelength other than λ1, λ2, and λ3) reflected by the first, second, and third wavelength selection filters 115a, 115b, and 115c is emitted from the input / output collimator 210. The position / orientation / tilt of the third wavelength selection filter 115c and the mirror 224 are adjusted so as to properly enter the fourth add / drop collimator 214.

  Also in this case, by inserting the third wavelength selection filter 115c, the optical axis incident on the third add / drop collimator 213 is shifted, but this is later changed from the input / output collimator 210 to the third wavelength selection. Finely adjust the direction and inclination of the mirror 223 so that the light having the transmission wavelength (λ3) of the filter 115c is emitted and the light transmitted through the filter 115c is appropriately incident on the third add / drop collimator 213. Thus, it can be easily corrected. Therefore, optical coupling equivalent to that before insertion of the filter can be obtained.

  Next, the fourth wavelength selection filter 115d is placed at a position where the light emitted from the input / output collimator 210 between the third wavelength selection filter 115c and the mirror 224 (reflected light of the wavelength selection filters 115a, 115b, and 115c) hits. Place. The fourth wavelength selection filter 115d also has a function capable of changing its own direction and inclination like the mirror. The light emitted from the input / output collimator 210 to the fifth add / drop collimator 214 and sequentially reflected by the first, second, third, and fourth wavelength selection filters 115a, 115b, 115c, and 115d. The mirror 225 is installed so that can enter. That is, light of wavelengths (wavelengths other than λ1, λ2, λ3, and λ4) reflected from the input / output collimator 210 by the first, second, third, and fourth wavelength selection filters 115a, 115b, 115c, and 115d. , And the positions, orientations, and inclinations of the fourth wavelength selection filter 115d and the mirror 225 are adjusted so that the light is properly incident on the fifth collimator 215 for branching and inserting.

  Also in this case, by inserting the fourth wavelength selection filter 115d, the optical axis incident on the fourth add / drop collimator 214 is shifted. The direction and inclination of the mirror 224 are finely adjusted so that the light having the transmission wavelength (λ4) of the filter 115d is emitted and the light transmitted through the filter 115d is appropriately incident on the fourth add / drop collimator 214. Thus, it can be easily corrected. Therefore, optical coupling equivalent to that before insertion of the filter can be obtained.

  Next, the case where this optical module 200 is used as a multiple wavelength optical demultiplexing device will be described. When used as an optical demultiplexing device, as shown in FIG. 2A, the input / output collimator 210 is an input collimator that receives wavelength multiplexed light from an external input optical transmission line, and the others. Are used as branching light collimators that extract the light transmitted or reflected by the wavelength selection filters 115a to 115d to the outside, and the wavelength selection filters 115a to 115d are used as optical elements for demultiplexing, so that wavelength multiplexed light can be obtained. Demonstrates the ability to demultiplex sequentially.

If wavelength multiplexed light having wavelengths λ1 to λ5 is input to the input / output collimator 210, only light having a wavelength of λ1 passes through the first wavelength selection filter 115a and is used for the first branch insertion. Light incident on the collimator 211 and having other wavelengths λ2 to λ5 is reflected toward the second wavelength selection filter 115b. Similarly, in the second wavelength selection filter 115b, only light having a wavelength of λ2 is transmitted and incident on the second add / drop collimator 212, and the other wavelengths λ3 to λ5 are transmitted by the third wavelength selection filter 115b. Reflected toward the filter 115c. In the third wavelength selection filter 115c, only light having a wavelength of λ3 is transmitted and incident on the third add / drop collimator 213, and the other wavelengths λ4 and λ5 are transmitted by the fourth wavelength selection filter. Reflected toward 115d. In the fourth wavelength selection filter 115d, only light having a wavelength of λ4 is transmitted and is incident on the fourth add / drop collimator 214, and other light of wavelength λ5 is directed to the fifth add / drop collimator 215. And reflected. Thereby, the light of each wavelength is demultiplexed sequentially.

  Next, the case where this optical module 200 is used as a multiple wavelength optical multiplexer will be described. When used as an optical multiplexing device, as shown in FIG. 2B, the input / output collimator 210 is an output light collimator that transmits output light to an external output optical transmission line, and other collimators are used. By using 211 to 215 as an insertion light collimator that makes light of different wavelengths incident on the wavelength selection filters 115a to 115d from the outside, and using the wavelength selection filters 115a to 115d as optical elements for multiplexing, Demonstrates the ability to combine light sequentially.

  Now, when light of wavelengths λ1 to λ5 is sequentially input to collimators 211 to 215 for branching and inserting, the light of wavelengths λ5 and λ4 is combined in the fourth wavelength selection filter 115d, and the third wavelength selection filter 115c. , The light of wavelengths λ5 to λ3 is combined, the light of wavelengths λ5 to λ2 is combined in the second wavelength selection filter 115b, and the light of wavelengths λ5 to λ1 is combined in the first wavelength selection filter 115a. . Then, the light emitted from the first wavelength selection filter 115a enters the input / output collimator 210 and is transmitted to the external optical transmission line.

  As described above, the optical module 200 of the present embodiment can be used as an optical demultiplexing device or can be used as an optical multiplexing device. In addition, in that case, since the optical axis shift that occurs when passing through each component is corrected by the mirrors 220 to 225 disposed between the wavelength selection filters 115a to 115d and the collimators 210 to 215, sufficient Optical coupling is obtained, and optical demultiplexing or optical multiplexing with little loss can be performed. Further, in this optical module 200, since each component is arranged on the substrate 230 so that light is spatially propagated between the components, a plurality of filter modules are used as in the prior art, and an optical fiber is used between the filter modules. Compared with the type of optical demultiplexing device or optical multiplexing device to be connected, it is possible to obtain an optical demultiplexing device or optical multiplexing device with low loss and a small size and low cost. In particular, the greater the number of channels, the more advantageous the optical module of this embodiment.

Next, a third embodiment of the present invention will be described.
FIG. 8 is a plan view showing the configuration of the optical modules 300 and 500 according to the third embodiment of the present invention. FIG. 8A is an optical module 300 using a total reflection prism as an optical path correction member, and FIG. Is an optical module 500 using a wedge-shaped prism. The optical module 300 shown in FIG. 8A has the same configuration as the optical module 100 shown in FIG. 1A except that the mirror is replaced with a total reflection prism, and the optical module shown in FIG. 500 has the same configuration as the optical module 100 shown in FIG. 1A except that the mirror is replaced with a wedge-shaped prism.
FIG. 9 is a plan view of a total reflection prism type optical module 400 according to the third embodiment of the present invention. FIG. 9A shows a case where the optical module 400 is used as an optical demultiplexing device, and FIG. This is when used as a device. The optical module 400 shown in FIGS. 9A and 9B has the same configuration as the optical module 200 shown in FIGS. 2A and 2B except that the mirror is replaced with a total reflection prism.
10A and 10B are plan views of a wedge-shaped prism optical module 600 according to the third embodiment of the present invention. FIG. 10A shows a case where the optical module 600 is used as an optical demultiplexer, and FIG. 10B shows an optical multiplexer. Is used as The optical module 600 shown in FIGS. 10A and 10B has the same configuration as the optical module 200 shown in FIGS. 2A and 2B except that the mirror is replaced with a wedge prism.

In the first and second embodiments of the present invention described above, the case where the mirror is used as the optical path correcting member has been described. As shown in FIGS. 8 to 10, even when this mirror is replaced with a prism, as shown in the optical modules 300, 400, 500, and 600, the same effect can be obtained. Of course, a member other than the mirror and the prism can be used as an optical path correcting member as long as it has a function of correcting the optical path with a predetermined accuracy.
If desired, these mirrors, prisms, and the like can be mixed and used in the optical module.

  In the optical modules 300 and 400 shown in FIGS. 8A and 9, when the total reflection prisms 301 to 304 and 410 to 415 are used as the optical path correction members, the signals are the same as when the mirror is used. We were able to correct the light path.

  Also, in the optical modules 500 and 600 shown in FIGS. 8B and 10, when the wedge-shaped prisms 501 to 504 and 610 to 615 having an arbitrary angle are used as the optical path correcting member, the refraction angle of the signal light is also obtained. By using, optical path correction can be performed in the same manner as when using a mirror.

  When the total reflection type or the wedge shape is used as the prism as the optical path correcting member, the same effect as that of the reflection mirror can be obtained by providing an antireflection film on the light transmission surface. In particular, in the case of a wedge-shaped prism, since there is no expansion of the beam generated by low-angle reflection, the prism itself can be made small, and there is also an advantage that the entire size can be reduced. Furthermore, as described with reference to the mirrors 121 to 124 in FIG. 1, the inclination of each prism is not fixed as long as it does not move during normal use, so that it can be finely adjusted later. You may keep it. For example, it is also preferable to use a prism that performs gimbal type position adjustment.

  The arrangement of each component such as each collimator, the optical path correction member, and the wavelength selection filter is not limited to the above embodiment, and other arrangements may be used as long as a necessary optical path can be formed. Moreover, although the case where the wavelength selection filter was used as an interference filter was shown in the said embodiment, you may use the interference filter which has another function. In addition to the collimator, the optical path correction member, and the filter, other optical components such as a polarizing element and a lens may be disposed on the same substrate as necessary.

  As described above, according to the present invention, the optical path correction mirror is disposed in the optical path between the collimator and the interference filter, and the optical axis deviation between the collimators is corrected by the optical path correction member. Therefore, good optical coupling can be realized. In addition, each component is fixed on a common board, and light is propagated between the components. This eliminates the use of unnecessary components, reduces the cost and size of the optical module with the minimum required volume. Can be achieved. According to the invention of claim 3, a low-loss optical add / drop multiplexer can be realized by performing good optical coupling. According to the invention of claim 4, a low-loss multi-wavelength optical demultiplexing device (invention of claim 5) and a multi-wavelength optical multiplexing device (invention of claim 6) can be made.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the optical module of 1st Embodiment of this invention, (a) is a top view, (b) is a side view. It is a top view of the optical module of 2nd Embodiment of this invention, (a) is explanatory drawing at the time of using as an optical demultiplexing apparatus, (b) is an explanatory view at the time of using as an optical multiplexing apparatus. It is a schematic block diagram of the conventional optical add / drop device. It is explanatory drawing of the optical axis shift of a collimator. It is a figure which shows the characteristic of the optical axis offset of a collimator. It is explanatory drawing of the optical axis shift of a wavelength selection filter. It is a figure which shows the characteristic of the optical axis offset of a wavelength selection filter. It is a top view which shows the structure of the optical module of 3rd Embodiment of this invention, (a) is a total reflection prism type | mold, (b) is a wedge-shaped prism type | mold. It is a top view of the total reflection prism type optical module of 3rd Embodiment of this invention, (a) is a case where it uses as an optical demultiplexing apparatus, (b) is a case where it uses as an optical multiplexing apparatus. It is a top view of the wedge-shaped prism type | mold optical module of 3rd Embodiment of this invention, (a) is a case where it uses as an optical demultiplexing apparatus, (b) is a case where it uses as an optical multiplexing apparatus.

Explanation of symbols

130, 230 Substrate 100, 200, 300, 400, 500, 600 Optical module 111 Collimator for input light 112 Collimator for output light 113 Collimator for branched light 114 Collimator for inserted light 115, 115a-115d Wavelength selection filters 121-124, 220 225 Mirrors as optical path correction members 301 to 304, 410 to 415 Reflective prisms as optical path correction members 501 to 504 and 610 to 615 Wedge prisms as optical path correction members 131 to 134 V-groove 210 to 215 Collimator

Claims (9)

In the optical path from the input light collimator to the output light collimator, the input light collimator that collimates the input light from the outside, the output light collimator that inputs the output light to the outside, collects it, and transmits it to the outside And a collimator mounted on a common rectangular substrate, and an optical path correcting flat mirror disposed in the optical path between each collimator and the interference filter, and each collimator, The V-grooves are formed in parallel to each other on the common rectangular substrate , and the V-groove is formed in parallel to one side of the common rectangular substrate .
Each of the collimators includes a collimating lens that is optically coupled to an optical fiber, and collimates the signal light of the optical fiber into parallel light and emits the light toward space, or parallel light that has been spatially transmitted. Fulfills the function of focusing and incident on the end face of the optical fiber,
The optical path after arranging the interference filter can be corrected by adjusting only the optical path correcting flat mirror,
As the interference filter,
(A) a wavelength selection filter that transmits only light in a specific wavelength band among incident light and reflects light of other wavelengths;
(B) a gain equalization filter that corrects the light intensity so as to flatten the intensity when the intensity of the incident light is not uniform with respect to the wavelength;
(C) a filter for extracting only a part of the amount of incident light;
An optical module characterized in that at least one of them is used . An input light collimator that collimates wavelength multiplexed light transmitted from the input optical transmission path into parallel light, and transmits only light in a specific wavelength band among wavelength multiplexed light incident through the input light collimator. A wavelength selective filter that reflects light in the wavelength band, a collimator for branching light that condenses light transmitted through the wavelength selective filter and transmits it to an external optical transmission line for branching, and an external optical transmission line for insertion A collimator for insertion light that collimates light of a specific wavelength band to be transmitted into parallel light and enters the wavelength selection filter, light that is transmitted through the wavelength selection filter by the collimator for insertion light, and the wavelength multiplexing A collimator for output light that condenses and transmits the combined light of the light reflected by the wavelength selection filter and transmitted to an external output optical transmission line, and each of the collimators and the wavelength selection filter And a flat mirror for optical path correction respectively disposed in the optical path between, be equipped with a respective collimator and the wavelength selection filter and a flat mirror for optical path correction on a common rectangular substrate, and each of said collimator The V-grooves formed in parallel to each other on the common rectangular substrate , and the V-grooves are formed in parallel to one side of the common rectangular substrate ;
Each of the collimators includes a collimating lens that is optically coupled to an optical fiber, and collimates the signal light of the optical fiber into parallel light and emits the light toward space, or parallel light that has been spatially transmitted. Fulfills the function of focusing and incident on the end face of the optical fiber,
The optical module after the wavelength selection filter is arranged can be corrected by adjusting only the optical path correcting flat plate mirror . A demultiplexing function that transmits only light of a specific wavelength and reflects light of other wavelengths, and light of a specific wavelength that is incident and transmitted from one surface and light of another wavelength that is incident and reflected from the other surface. Equipped with a plurality of wavelength selection filters having a multiplexing function for multiplexing, with different specific wavelengths,
The plurality of wavelength selective filters are arranged so that the reflected light of the filters enters in order from the upstream side to the downstream side in the light traveling direction,
Collimators are arranged on the optical path of the incident light to the most upstream wavelength selective filter, on the optical path of the transmitted light of each wavelength selective filter, and on the optical path of the reflected light of the downstream downstream wavelength selective filter,
An optical path correction plate mirror is arranged in the optical path between each collimator and the wavelength selection filter,
The collimators, wavelength selection filters, and optical path correcting flat mirrors are arranged on a common rectangular substrate , and the collimators are arranged in V-grooves formed in parallel to each other on the common rectangular substrate , Further, the V-groove is formed in parallel to one side of the common rectangular substrate ,
Each of the collimators includes a collimating lens that is optically coupled to an optical fiber, and collimates the signal light of the optical fiber into parallel light and emits the light toward space, or parallel light that has been spatially transmitted. Fulfills the function of focusing and incident on the end face of the optical fiber,
The optical module after the wavelength selection filter is arranged can be corrected by adjusting only the optical path correcting flat plate mirror . In the optical module according to claim 3 , the most upstream collimator is an input light collimator that receives wavelength multiplexed light from an external input optical transmission line, and the other collimators are the wavelength selection filter. A multi-wavelength optical demultiplexing device that sequentially demultiplexes wavelength-multiplexed light is configured by using a branching light collimator for extracting transmitted or reflected light to the outside and using the wavelength selection filter as a demultiplexing optical element. An optical module characterized by that. The most downstream collimator of the optical module according to claim 3 is an output light collimator that transmits output light to an external output optical transmission line, and other collimators are externally connected to the wavelength selection filter. On the other hand, a multi-wavelength optical multiplexing device that sequentially multiplexes light of different wavelengths is configured by using an insertion light collimator for entering light of different wavelengths and using the wavelength selection filter as an optical element for multiplexing. A featured optical module. The optical module according to the collimator, and the optical fiber, to any one of claims 1 to 5, characterized in that is constituted by a collimating lens disposed on the exit end or entrance end of the optical fiber. In the optical path from the input light collimator to the output light collimator, the input light collimator that collimates the input light from the outside, the output light collimator that inputs the output light to the outside, collects it, and transmits it to the outside And an optical path correcting prism respectively disposed in an optical path between each collimator and the interference filter on a common rectangular substrate, and each collimator is It is arranged in a V-groove formed in parallel with each other on a common rectangular substrate , and this V-groove is formed in parallel with one side of the common rectangular substrate ,
Each of the collimators includes a collimating lens that is optically coupled to an optical fiber, and collimates the signal light of the optical fiber into parallel light and emits the light toward space, or parallel light that has been spatially transmitted. Fulfills the function of focusing and incident on the end face of the optical fiber,
The optical path after placing the interference filter can be corrected by adjusting only the optical path correcting prism,
As the interference filter,
(A) a wavelength selection filter that transmits only light in a specific wavelength band among incident light and reflects light of other wavelengths;
(B) a gain equalization filter that corrects the light intensity so as to flatten the intensity when the intensity of the incident light is not uniform with respect to the wavelength;
(C) a filter for extracting only a part of the amount of incident light;
An optical module characterized in that at least one of them is used . The optical module according to any one of claims 1 to 6, characterized in that the flat-plate mirror for optical path correction, using a gimbal-type mirror. The optical module according to claim 7 , wherein a total reflection prism that performs gimbal-type position adjustment is used as the optical path correction prism.

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