Optical circuit board and optical component mounting structure

Abstract

An optical circuit board according to the present disclosure can easily determine an irradiation position of light when performing inspection and can efficiently perform the inspection of an optical waveguide.　An optical circuit board (1) according to the present disclosure includes a wiring board (2), and a first optical waveguide (31) and a second optical waveguide (32) positioned on the wiring board (2). The first optical waveguide (31) includes first lower cladding (311), a first core (312), and first upper cladding (313) covering at least a portion of the fire core. The second optical waveguide (32) includes second lower cladding (321), a second core (322), and second upper cladding (323) covering at least a portion of the second core. The second optical waveguide (32) has a first end face (3a) where a first core end face (322a) of a second core is exposed to an outer edge side of a wiring board, and a second end face (3b) where a second core end face (322b) of a second core is exposed to the central side of the wiring board. A gap (324) is present between the second core (322) and the second upper cladding (323) at the first end face (3a) and / or second end face (3b).

Description

Technical Field

[0001] The present invention relates to an optical circuit board and an optical component mounting structure using the same.

Background Art

[0002] In recent years, optical fibers capable of communicating a large amount of data at high speed have been used in information communication. Transmission and reception of optical signals are performed between this optical fiber and optical components. Such optical components are mounted on, for example, an optical circuit board. The optical circuit board is provided with an optical waveguide. Optical signals are transmitted and received through this optical waveguide. The optical circuit board used for transmission and reception of optical signals needs to be inspected to determine whether transmission and reception of optical signals are performed normally, as described in, for example, Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Means for Solving the Problems

[0004] The optical circuit board according to the present disclosure includes a wiring board, a first optical waveguide located on the wiring board, and a second optical waveguide located adjacent to the first optical waveguide on the wiring board. The first optical waveguide includes a first lower cladding located on the wiring board, a first core extending from the outer edge side to the central side of the wiring board on the first lower cladding, and a first upper cladding covering at least a part of the first core. The second optical waveguide includes a second lower cladding located on the wiring board, a second core located along the first core on the second lower cladding, and a second upper cladding covering at least a part of the second core. The second optical waveguide has a first end face on the outer edge side of the wiring board where a first end face of the second core is exposed, and a second end face on the central side of the wiring board where a second end face of the second core is exposed. A gap exists between the second core and the second upper cladding at at least one of the first end face and the second end face.

[0005] The optical component mounting structure according to the present disclosure has the above optical circuit board and an optical component mounted on the optical circuit board.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0007] For the optical conduction inspection, it is necessary to irradiate each core included in the optical waveguide with a thin light beam (for example, about 9 μm in diameter). However, in a conventional optical circuit board, it is difficult to visually recognize the core at the end face of the optical waveguide, and it is difficult to position the light beam for irradiation. Therefore, there is a need for an optical circuit board that can easily determine the light incident position during inspection and has excellent inspection efficiency for the optical waveguide.

[0008] The optical circuit board according to the present disclosure has a configuration as described in the section of means for solving the problems, and thus can easily determine the light incident position during inspection and can efficiently perform the inspection of the optical waveguide.

[0009] The optical circuit board according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 4. FIG. 1 is a plan view showing an optical component mounting structure 10 in which an optical component 4 is mounted on an optical circuit board 1 according to an embodiment of the present disclosure.

[0010] The optical circuit board 1 according to an embodiment of the present disclosure includes a wiring board 2 and an optical waveguide 3. Examples of the wiring board 2 included in the optical circuit board 1 according to an embodiment include wiring boards generally used for optical circuit boards.

[0011] Although such a wiring board 2 is not specifically illustrated, for example, it includes a core board and build-up layers laminated on both surfaces of the core board. The core board is not particularly limited as long as it is a material having insulating properties. Examples of the material having insulating properties include resins such as epoxy resin, bismaleimide-triazine resin, polyimide resin, and polyphenylene ether resin. These resins may be used in a mixture of two or more. The core board usually has through-hole conductors for electrically connecting the upper and lower surfaces of the core board.

[0012] The core substrate may contain a reinforcing material. Examples of the reinforcing material include insulating cloth materials such as glass fiber, glass non-woven fabric, aramid non-woven fabric, aramid fiber, and polyester fiber. Two or more kinds of reinforcing materials may be used in combination. Further, inorganic fillers such as silica, barium sulfate, talc, clay, glass, calcium carbonate, and titanium oxide may be dispersed in the core substrate.

[0013] The build-up layer has a structure in which an insulating layer and a conductor layer are alternately laminated. A part of the conductor layer located on the outermost surface (the conductor layer located on the upper surface of the wiring substrate 2) includes the conductor layer 21a where the optical waveguide 3 is located. The conductor layer 21a is formed of a metal such as copper, for example. The insulating layer included in the build-up layer is not particularly limited as long as it is a material having insulating properties, similar to the core substrate. Examples of the material having insulating properties include resins such as epoxy resin, bismaleimide-triazine resin, polyimide resin, and polyphenylene ether resin. These resins may be used by mixing two or more kinds.

[0014] When there are two or more insulating layers in the build-up layer, each insulating layer may be the same resin or different resins. The insulating layer included in the build-up layer and the core substrate may be the same resin or different resins. The build-up layer usually has via hole conductors for electrically connecting the layers.

[0015] Further, inorganic fillers such as silica, barium sulfate, talc, clay, glass, calcium carbonate, and titanium oxide may be dispersed in the insulating layer included in the build-up layer.

[0016] As shown in FIG. 2, the optical waveguide 3 included in the optical circuit substrate 1 according to one embodiment is located on the upper surface of the conductor layer 21a existing on the upper surface of the wiring substrate 2. FIG. 2 is an enlarged explanatory view for explaining the cross section of the region R1 shown in FIG. 1. One end of the optical waveguide 3 faces an optical component 4 including an optical transmission path 41. The other end of the optical waveguide 3 is connected to an optical connector 5a including an optical fiber 5.

[0017] As shown in FIG. 3, the optical waveguide 3 includes a first optical waveguide 31 and a second optical waveguide 32. FIG. 3 is a plan view seen from the direction of arrow A shown in FIG. 2. As shown in FIG. 4, the first optical waveguide 31 includes a first lower cladding 311, a first core 312, and a first upper cladding 313. FIG. 4 is an explanatory diagram for explaining a cross section cut along the X-X line shown in FIG. 3.

[0018] The first lower cladding 311 included in the first optical waveguide 31 is located on the upper surface of the wiring substrate 2, specifically, on the upper surface of the conductor layer 21a existing on the upper surface of the wiring substrate 2. The material forming the first lower cladding 311 is not limited, and examples include resins such as epoxy resin and silicone resin.

[0019] The first core 312 included in the first optical waveguide 31 is located on the upper surface of the first lower cladding 311. The first core 312 extends from the outer edge side of the wiring substrate 2 to the central side of the wiring substrate 2. In other words, in FIG. 2, the outer edge side of the wiring substrate 2 refers to the side (outer peripheral portion) where the optical connector 5a is located, and the central side of the wiring substrate 2 refers to the side where the optical component 4 is located. The first core 312 is the portion where the light that has entered the first optical waveguide 31 propagates. That is, optical signals are transmitted and received between the first core 312 and the optical transmission path 41. Therefore, one end face of the first core 312 is positioned to face the end face of the optical transmission path 41 included in the optical component 4 mounted on the wiring substrate 2.

[0020] The material forming the first core 312 is not limited and is appropriately set in consideration of, for example, light transmittance and wavelength characteristics of the propagating light. Examples of the material include resins such as epoxy resin and silicone resin. The first core 312 has a thickness of, for example, about 3 μm or more and 50 μm or less.

[0021] The first upper cladding 313 included in the first optical waveguide 31 is positioned so as to cover at least a part of the first core 312. Similar to the first lower cladding 311, the first upper cladding 313 is formed of a resin such as an epoxy resin or a silicone resin. The first lower cladding 311 and the first upper cladding 313 may be made of the same material or different materials. Further, the first lower cladding 311 and the first upper cladding 313 may have the same thickness or different thicknesses. The first lower cladding 311 and the first upper cladding 313 have a thickness of, for example, about 5 μm or more and 150 μm or less.

[0022] The second optical waveguide 32 is positioned adjacent to the first optical waveguide 31. Specifically, the second optical waveguide 32 is positioned along the first optical waveguide 31 so as to sandwich the first optical waveguide 31. The second optical waveguide 32 is used for positioning to make light rays incident when performing a light conduction inspection on the first optical waveguide 31.

[0023] The second lower cladding 321 included in the second optical waveguide 32 is positioned on the upper surface of the wiring substrate 2, specifically, on the upper surface of the conductor layer 21a existing on the upper surface of the wiring substrate 2, similar to the first lower cladding 311. The material forming the second lower cladding 321 is not limited, and examples include resins such as epoxy resins and silicone resins similar to the first lower cladding 311. The second lower cladding 321 may be formed of the same material (resin) as the first lower cladding 311 or a different material (resin).

[0024] As shown in FIG. 4, the second lower cladding 321 may be integrated with the first lower cladding 311 or may be independent of the first lower cladding 311. For example, when the second lower cladding 321 and the first lower cladding 311 are integrated, the processes for forming the first optical waveguide 31 and the second optical waveguide 32 can be simplified.

[0025] The second core 322 included in the second optical waveguide 32 is located on the upper surface of the second lower cladding 321. The second core 322 is located along the first core 312 included in the first optical waveguide 31. The material forming the second core 322 is not limited, and similar to the material forming the first core 312, examples include resins such as epoxy resin and silicone resin. Usually, since the first core 312 and the second core 322 are formed simultaneously, the material (resin) forming the first core 312 and the material (resin) forming the second core 322 may be the same. The second core 322, similar to the first core 312, has a thickness of, for example, about 3 μm or more and 50 μm or less.

[0026] The second optical waveguide 32 has a first end face 3a on the outer edge side of the wiring board 2 and a second end face 3b on the central side of the wiring board 2. That is, in FIG. 3, the end face located on the optical connector 5a side is the first end face 3a, and the end face located on the optical component 4 side is the second end face 3b. The second core 322 has a first core end face 322a on the outer edge side of the wiring board 2 and a second core end face 322b on the central side of the wiring board 2. That is, the first core end face 322a is a part of the first end face 3a, and the second core end face 322b is a part of the second end face 3b.

[0027] The second upper cladding 323 included in the second optical waveguide 32 is located so as to cover at least a part of the second core 322. Regarding the second upper cladding 323 as well, similar to the second lower cladding 321, it is formed of a resin such as epoxy resin or silicone resin. The second lower cladding 321 and the second upper cladding 323 may be the same material or different materials. Further, the second lower cladding 321 and the second upper cladding 323 may have the same thickness or different thicknesses. The second lower cladding 321 and the second upper cladding 323 have a thickness of, for example, about 5 μm or more and 150 μm or less. The second upper cladding 323 is usually formed simultaneously with the first upper cladding 313 included in the first optical waveguide 31. Therefore, the second upper cladding 323 may have the same thickness as the first upper cladding 313.

[0028] As described above, the second lower cladding 321 may be integrated with the first lower cladding 311. On the other hand, as shown in FIG. 4, the second upper cladding 323 may be positioned independently of the first upper cladding 313. When the second upper cladding 323 is positioned independently of the first upper cladding 313, even if the second upper cladding 323 is separated from the second core 322, it is less likely to affect the first core 312 where optical signals are transmitted and received.

[0029] There is a gap 324, for example, as shown in FIG. 4, between the second core 322 and the second upper cladding 323 at at least one of the first end face 3a and the second end face 3b of the second optical waveguide 32. The presence of such a gap 324 allows the gap 324 to be visually recognized when performing an optical continuity inspection. As a result, the position of the second core 322 can be recognized, and based on the position of the second core 322, the position of the first core 312 where the optical continuity inspection is performed can be easily recognized.

[0030] The reason for not forming a gap 324 between the first core 312 and the first upper cladding 313 is that if there is a gap 324 between the first core 312 and the first upper cladding 313, the transmission loss will increase. Therefore, a second core 322 that does not transmit and receive optical signals is formed, and a visually recognizable gap 324 is formed in the vicinity of the second core 322. Positioning for injecting light rays into the first core 312 is performed based on the visually recognizable gap 324.

[0031] The second core 322 may have a plurality of side surfaces connecting the first core end face 322a and the second core end face 322b. The number of these side surfaces varies depending on the cross-sectional shape of the second core 322. For example, as shown in FIG. 4, when the cross-sectional shape of the second core 322 is a quadrilateral, the number of side surfaces is two. That is, when the second core 322 is viewed in cross-section, the surfaces other than the surface in contact with the second lower cladding 321 and the surface opposite thereto are the side surfaces. For example, when the cross-sectional shape of the second core 322 is a hexagon, the number of side surfaces is four.

[0032] Among the plurality of side surfaces of the second core 322, a gap 324 may exist between at least one side surface and the second upper cladding 323. By the existence of the gap 324 between at least one side surface and the second upper cladding 323, the lower surface of the second core 322 is in contact with the second lower cladding 321, and the upper surface of the second core 322 is in contact with the second upper cladding 323. As a result, it is possible to reduce the peeling of the second core 322 from the second lower cladding 321 or the second upper cladding 323.

[0033] The plurality of side surfaces of the second core 322 include, for example, a first side surface and a second side surface facing each other, and the gap 324 may exist on both the first side surface and the second side surface. Specifically, when the cross-sectional shape of the second core 322 is a quadrilateral, the two side surfaces face each other, one side surface is the first side surface, and the other side surface is the second side surface. By the existence of the gap 324 on both the opposing first side surface and the second side surface, the position of the second core 322 can be visually recognized more accurately. As a result, the incident positioning of the light beam can be performed with higher accuracy. The gaps 324 located on each of the first side surface and the second side surface may be plural, or only one of them may be plural. Further, the gap 324 may be continuously located between the first core end surface 322a and the second core end surface 322b, or may be intermittently located.

[0034] A plurality of gaps 324 may exist at least on one of the first end surface 3a and the second end surface 3b. For example, in FIG. 4, two gaps 324 exist, one each, between both side surfaces (the first side surface and the second side surface) of the second core 322 and the second upper cladding 323. By the existence of a plurality of gaps 324, the visibility can be improved. As a result, the incident positioning of the light beam can be performed with higher accuracy. In FIG. 4, one gap 324 exists on one side surface, but a plurality of gaps 324 may exist on one side surface.

[0035] The gap 324 existing between at least one side surface of the second core 322 and the second upper cladding 323 may be in contact with the second lower cladding 321 or may be separated from the second lower cladding 321. For example, when the gap 324 is in contact with the second lower cladding 321, the boundary between the second lower cladding 321 and the second core 322 becomes easier to recognize. As a result, the incident positioning of light rays in the height direction of the first optical waveguide 31 can be performed with higher accuracy.

[0036] The gap 324 may continuously exist from the first end face 3a to the second end face 3b or may intermittently exist. When the gap 324 continuously exists, when forming the optical waveguide 3, for example, when cutting both ends to form the first end face 3a and the second end face 3b, no matter which part is cut, the gap 324 can be made to exist on the first end face 3a and the second end face 3b. When the gap 324 intermittently exists, it is advantageous in terms of ensuring the adhesion between the second core 322 and the second upper cladding 323.

[0037] As described above, according to the present disclosure, the inspection efficiency of the optical waveguide 3 can be improved by the second core 322, and the optical circuit board 1 excellent in optical transmission can be provided.

[0038] Next, an embodiment of a method for forming the first optical waveguide 31 and the second optical waveguide 32 will be described with reference to FIG. 5. FIG. 5 is an explanatory diagram for explaining the steps of forming the first optical waveguide 31 and the second optical waveguide 32 in the optical circuit board 1 according to an embodiment. In FIG. 5, the figures described on the right side show enlarged views of the regions surrounded by the dashed-dotted lines in the figures described on the left side.

[0039] First, the first lower cladding 311 and the second lower cladding 321 are formed on the upper surface of the wiring substrate 2 (conductor layer 21a). The first lower cladding 311 and the second lower cladding 321 are as described above, and detailed descriptions thereof are omitted. The first lower cladding 311 and the second lower cladding 321 shown in FIG. 5 are integrated.

[0040] As shown in FIG. 5(A), the materials of the first core 312 and the second core 322 are arranged on the upper surfaces of the first lower cladding 311 and the second lower cladding 321. Examples of such materials include uncured resins such as epoxy resin and silicone resin.

[0041] Next, an exposure mask M1 is arranged so as to cover the uncured resin. The exposure mask M1 has an opening, and the first core 312 and the second core 322 are formed at the position of this opening. After arranging the exposure mask M1, by performing exposure and development, as shown in FIG. 5(B), the first core 312 is formed on the upper surface of the first lower cladding 311, and the second core 322 is formed on the upper surface of the second lower cladding 321. During exposure, even the portion covered by the exposure mask M1 is slightly affected by exposure near the opening. Therefore, there is uncured resin near the side surfaces of the first core 312 and the second core 322.

[0042] Next, as shown in FIG. 5(C), the materials of the first upper cladding 313 and the second upper cladding 323 are arranged so as to cover the first core 312 and the second core 322. Examples of such materials include uncured resins such as epoxy resin and silicone resin. Next, a halftone mask M2 is arranged so as to cover this uncured resin.

[0043] The halftone mask M2 is a mask having a halftone portion H where the transmittance is lowered and the exposure amount is suppressed. The transmittance of the halftone portion H is, for example, about 40% of the normal (specifically, about 40 ± 10%). The boundary between the first upper cladding 313 and the second upper cladding 323 is shielded so as not to be exposed. After arranging the halftone mask M2, by performing exposure and development, as shown in FIG. 5(D), the first upper cladding 313 is formed so as to cover the first core 312, and the second upper cladding 323 is formed so as to cover the second core 322. Since the boundary between the first upper cladding 313 and the second upper cladding 323 is shielded so as not to be exposed and does not cure, the first upper cladding 313 and the second upper cladding 323 are positioned independently.

[0044] The portion corresponding to the second optical waveguide 32 has, for example, as described above, resin with insufficient curing near the side surface of the second core 322. Further, the portion corresponding to the second optical waveguide 32 is exposed with a light amount smaller than the exposure amount of the first upper cladding 313 during the exposure of the second upper cladding 323. As a result, in particular, the curing reaction between the side surface of the second core 322 and the second upper cladding 323 does not proceed, and the gap 324 is likely to be formed.

[0045] The portion corresponding to the first optical waveguide 31 is exposed with a transmittance necessary for curing during the exposure of the first upper cladding 313. Therefore, the resin with insufficient curing existing near the side surface of the first core 312 and the curing reaction of the first upper cladding 313 proceed sufficiently. As a result, the first core 312 and the first upper cladding 313 are sufficiently adhered, and the gap 324 is not formed.

[0046] Next, an optical component mounting structure 10 in which an optical component 4 and an electronic component 6 are mounted on an optical circuit board 1 according to an embodiment will be described. As shown in FIG. 1, the optical component 4 mounted on the optical component mounting structure 10 according to an embodiment includes an optical transmission path 41. Examples of the optical component 4 including such an optical transmission path 41 include a silicon photonics device. Examples of the electronic component 6 include an ASIC (Application Specific Integrated Circuit), a driver IC, and the like.

[0047] As shown in FIG. 2, the optical component 4 is electrically connected to a pad 21b located in the mounting area (area for mounting the optical component 4) of the wiring board 2 via a solder 7. The pad 21b is a part of a conductor layer located on the upper surface of the wiring board 2.

[0048] As an example of the optical component 4, a silicon photonics device will be described. The silicon photonics device is a type of optical component having, for example, an optical transmission path 41 with silicon (Si) as the core and silicon dioxide (SiO2) as the cladding. The silicon photonics device includes an Si waveguide as the optical transmission path 41 and further includes, although not shown, a passivation film, a light source unit, a photodetection unit, and the like. As described above, the optical transmission path 41 (Si waveguide 41) is positioned to face the first core 312 included in the first optical waveguide 31 at one end of the first optical waveguide 31.

[0049] For example, an electrical signal from the wiring board 2 is propagated to the light source unit included in the optical component 4 (silicon photonics device) via the solder 7. The light source unit that has received the propagated electrical signal emits light. The emitted optical signal is propagated to the optical fiber 5 connected via the optical connector 5a via the optical transmission path 41 (Si waveguide 41) and the first core 312. Since the optical component mounting structure 10 in one embodiment of the present disclosure mounts the optical component 4 on the optical circuit board 1 excellent in optical transmission, it is possible to reduce optical transmission loss.

[0050] The embodiments of the present disclosure have been described above. However, the invention according to the present disclosure is not limited to the above-described embodiments, and various changes and improvements are possible within the scope of the present disclosure shown in the following (1) and (8).

[0051] (1) The optical circuit board according to the present disclosure includes a wiring board, a first optical waveguide located on the wiring board, and a second optical waveguide located adjacent to the first optical waveguide on the wiring board. The first optical waveguide includes a first lower cladding located on the wiring board, a first core extending from the outer edge side to the central side of the wiring board on the first lower cladding, and a first upper cladding covering at least a part of the first core. The second optical waveguide includes a second lower cladding located on the wiring board, a second core located along the first core on the second lower cladding, and a second upper cladding covering at least a part of the second core. The second optical waveguide has a first end face on the outer edge side of the wiring board where a first end face of the second core is exposed, and a second end face on the central side of the wiring board where a second end face of the second core is exposed. In at least one of the first end face and the second end face, a gap exists between the second core and the second upper cladding.

[0052] Regarding the embodiments of the present disclosure, the embodiments shown in the following (2) to (7) are further disclosed.

[0053] (2) In the optical circuit board described in (1) above, the second core has a plurality of side faces connecting the first core end face and the second core end face, and a gap exists between at least one of the plurality of side faces of the second core and the second upper cladding. (3) In the optical circuit board described in (1) or (2) above, the gap exists continuously or intermittently from the first end face to the second end face. (4) In the optical circuit board described in any one of (1) to (3) above, a plurality of gaps exist in at least one of the first end face and the second end face. (5) In the optical circuit board described in any one of (1) to (4) above, the gap is in contact with the second lower cladding. (6) In the optical circuit board described in any one of (2) to (5) above, the plurality of side faces of the second core include a first side face and a second side face facing each other, and the gap exists on both sides of the first side face and the second side face. (7) In the optical circuit board according to any one of (1) to (6) above, the first lower cladding and the second lower cladding are integrated.

[0054] (8) The optical component mounting structure according to the present disclosure includes the optical circuit board according to any one of (1) to (7) above and an optical component mounted on the optical circuit board.

Explanation of Reference Numerals

[0055] 1 Optical circuit board 2 Wiring board 21a Conductor layer 21b Pad 3 Optical waveguide 31 First optical waveguide 311 First lower cladding 312 First core 313 First upper cladding 32 Second optical waveguide 321 Second lower cladding 322 Second core 322a First core end face 322b Second core end face 323 Second upper cladding 324 Gap 3a First end face 3b Second end face 4 Optical component 41 Optical transmission path (silicon waveguide (Si waveguide)) 5 Optical fiber 5a Optical connector 6 Electronic component 7 Solder 10 Optical component mounting structure

Claims

1. A wiring board, a first optical waveguide located on the wiring board, a second optical waveguide located on the wiring board adjacent to the first optical waveguide, comprising: the first optical waveguide includes a first lower cladding located on the wiring board, a first core extending from the outer edge side to the center side of the wiring board on the first lower cladding, and a first upper cladding covering at least a part of the first core; the second optical waveguide includes a second lower cladding located on the wiring board, a second core located along the first core on the second lower cladding, and a second upper cladding covering at least a part of the second core; the second optical waveguide has a first end face on the outer edge side of the wiring board where a first end face of the second core is exposed, and a second end face on the center side of the wiring board where a second end face of the second core is exposed; a gap exists between the second core and the second upper cladding at at least one of the first end face and the second end face, an optical circuit board.

2. the second core has a plurality of side faces connecting the first core end face and the second core end face, a gap exists between at least one of the plurality of side faces of the second core and the second upper cladding, the optical circuit board according to claim 1.

3. the gap exists continuously or intermittently from the first end face to the second end face, the optical circuit board according to claim 1.

4. a plurality of gaps exist at at least one of the first end face and the second end face, the optical circuit board according to claim 1.

5. the gap is in contact with the second lower cladding, the optical circuit board according to claim 1.

6. the plurality of side faces of the second core include a first side face and a second side face facing each other, the gap exists on both the first side face and the second side face, the optical circuit board according to claim 2.

7. the first lower cladding and the second lower cladding are integrated, the optical circuit board according to claim 1.

8. an optical circuit board according to any one of claims 1 to 7, an optical component mounted on the optical circuit board, an optical component mounting structure having the same.

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