Electromagnetic flux control member and communication module

Abstract

The present invention relates to providing an electromagnetic flux control member that is easy to manufacture by injection molding, while also functioning to suppress the reflection of electromagnetic waves. The electromagnetic flux control member according to the present invention has: a first area for allowing electromagnetic waves to enter or for allowing electromagnetic waves that have traveled through the interior to exit to the outside; a second area for allowing electromagnetic waves that have entered the first area to exit to the outside or for allowing electromagnetic waves to enter; a plurality of ribs arranged in the first area and / or the second area; and a gate vestige or gate mark on a lateral surface of the electromagnetic flux control member, wherein the plurality of ribs extend in the direction along the direction of the flow of material from the gate.

Description

Electromagnetic flux control member and communication module

[0001] The present invention relates to an electromagnetic flux control member and a communication module.

[0002] Components for controlling electromagnetic waves are known. For example, components for controlling light, which is a type of electromagnetic wave, are called optical elements, and optical elements control light by appropriately designing the shape of the surface where light enters and exits. For example, in Patent Document 1, a fine uneven shape is provided on part of the element surface of an optical element to provide an anti-reflection function.

[0003] Japanese Patent Application Laid-Open No. 2007-171857

[0004] The structure for suppressing the reflection of electromagnetic waves as described above is designed to have an optimal shape to exhibit the function of suppressing the reflection of electromagnetic waves. However, this shape for suppressing the reflection of electromagnetic waves may be undesirable from the viewpoint of manufacturing. For example, the fine uneven shape for suppressing reflection as described in Patent Document 1 is difficult to manufacture by injection molding.

[0005] An object of the present invention is to provide an electromagnetic flux control member that has the function of suppressing reflection of electromagnetic waves and that can be easily manufactured by injection molding, and a communication module that includes the electromagnetic flux control member.

[0006] The present invention relates to the following electromagnetic flux control member and communication module: [1] An electromagnetic flux control member having a first region for inputting electromagnetic waves or for outputting electromagnetic waves that have traveled inside the member to the outside, and a second region for outputting electromagnetic waves input in the first region or for inputting electromagnetic waves, the electromagnetic flux control member having a plurality of ribs arranged in at least one of the first region and the second region and gate remnants or gate marks on a side surface of the electromagnetic flux control member, the plurality of ribs extending in a direction along the inflow direction of material from a gate. [2] The electromagnetic flux control member according to [1], which is manufactured by an injection molding process and has a circular shape in plan view with cutouts that form chords by cutting out a circle, and the gate remnants or gate marks of the gate for inflowing resin used in the injection molding process are arranged in the cutouts. [3] The electromagnetic flux control member according to any one of [1] to [2], wherein the plurality of ribs are arranged in parallel in a plan view, the center-to-center distance of the plurality of ribs is 0.1 mm to 1 mm, and the height of the plurality of ribs is 0.05 mm to 1 mm in a plan view. [4] The electromagnetic flux control member according to any one of [1] to [3], wherein the dielectric constant of a material constituting the electromagnetic flux control member is 7 or more. [5] A communication module comprising a primary radiator and the electromagnetic flux control member according to any one of [1] to [4], wherein the direction in which the plurality of ribs extend intersects with the vibration direction of the electric field of the electromagnetic wave emitted from the primary radiator. [6] The communication module according to [5], wherein the gate remnant or gate mark is a positioning portion for determining the arrangement direction of the electromagnetic flux control member with respect to the vibration direction of the electric field of the electromagnetic wave. [7] A communication module having a primary radiator and the electromagnetic flux control member according to any one of [1] to [4], wherein a direction in which the plurality of ribs extend intersects with a vibration direction of an electric field of an electromagnetic wave emitted from the primary radiator, and the cutout portion is a positioning portion for determining an arrangement direction of the electromagnetic flux control member with respect to the vibration direction of the electric field of the electromagnetic wave. [8] The communication module according to any one of [5] to [7], wherein a wavelength of the electromagnetic wave emitted from the primary radiator is 0.1 mm to 10 mm.

[0007] According to the present invention, it is possible to provide an electromagnetic flux control member that has the function of suppressing reflection of electromagnetic waves and that can be easily manufactured by injection molding, and a communication module that has the electromagnetic flux control member.

[0008] FIG. 1 is a diagram showing a communication module according to an embodiment. FIGS. 2A and 2B are diagrams showing an electromagnetic flux control member according to an embodiment. FIG. 3A is a cross-sectional view of the electromagnetic flux control member, and FIGS. 3B and 3C are partially enlarged cross-sectional views of the electromagnetic flux control member. FIG. 4A is a diagram showing a gate of the electromagnetic flux control member, FIG. 4B is a diagram showing a gate remnant, and FIG. 4C is a diagram showing a gate mark. FIG. 5 is a diagram showing an electromagnetic flux control member having two cutout portions. FIG. 6A shows a state in which the gate remnant is used as a positioning portion for determining the arrangement direction of the electromagnetic flux control member, and FIG. 6B shows a state in which the cutout portion is used as a positioning portion for determining the arrangement direction of the electromagnetic flux control member.

[0009] 1 , communication module 100 according to the present embodiment has primary radiator 200 and electromagnetic flux control member 300. Communication module 100 may be used as a transmitting module or a receiving module.

[0010] When communication module 100 is used as a transmitting module, the electromagnetic waves radially propagating from primary radiator 200 are controlled to become substantially parallel electromagnetic waves by electromagnetic flux control member 300. The electromagnetic waves controlled to become substantially parallel are received by a receiving unit located at a distance.

[0011] When communication module 100 is used as a receiving module, electromagnetic waves emitted from a distant transmitter are controlled by electromagnetic flux control member 300 and converged on and received by primary radiator 200. Primary radiator 200 and electromagnetic flux control member 300 of communication module 100 will be described below.

[0012] (Primary Radiator) The primary radiator 200 may function as a transmitter that transmits electromagnetic waves, or as a receiver that receives electromagnetic waves. It is preferable that the primary radiator 200 can transmit or receive polarized waves.

[0013] The electromagnetic waves to be transmitted or received are not particularly limited, but are preferably millimeter waves, quasi-millimeter waves, or terahertz waves. More specifically, the band of the electromagnetic waves is preferably 30 GHz to 3 THz (wavelength of approximately 10 mm to approximately 0.1 mm), and more preferably 30 GHz to 300 GHz. Examples of primary radiator 200 include a horn antenna, a waveguide, and the like. In this embodiment, primary radiator 200 is a waveguide. By directly combining the waveguide and electromagnetic flux control member 300, the distance between the waveguide and electromagnetic flux control member 300 can be narrowed, and communication module 100 can be made more compact.

[0014] (Electromagnetic Flux Controlling Member) Fig. 2A is a plan view of electromagnetic flux controlling member 300, and Fig. 2B is a side view. Fig. 3A is a cross-sectional view taken along line AA in Fig. 2A, and Figs. 3B and 3C are partially enlarged views of the cross-sectional view.

[0015] The electromagnetic flux control member 300 controls electromagnetic waves from or to the primary radiator 200. The dielectric constant of the material constituting the electromagnetic flux control member 300 is preferably 7 or greater, more preferably 10 or greater. Achieving a dielectric constant of 7 or greater may require adding an additive to the material (e.g., thermoplastic resin) constituting the electromagnetic flux control member 300. This may result in the material constituting the electromagnetic flux control member 300 becoming highly viscous or a molded product using the material becoming brittle, making it difficult to manufacture the electromagnetic flux control member 300 by injection molding. However, according to the electromagnetic flux control member 300 of the embodiment of the present invention, as described below, multiple ribs 330 for suppressing electromagnetic wave reflection extend in a direction substantially parallel to the flow direction of the material from the gate. This allows the electromagnetic flux control member 300 to function as a reflection suppressor while also being easily manufactured by injection molding. Furthermore, the dielectric loss tangent of the material constituting the electromagnetic flux control member 300 is preferably less than 0.01. If the dielectric loss tangent of the material is less than 0.01, loss within electromagnetic flux control member 300 is small, and desired characteristics (desired gain) tend to be obtained. When electromagnetic flux control member 300 is manufactured by injection molding, it is preferable that the thickness be constant to maintain productivity. In this embodiment, the thickest part of the electromagnetic flux control member is 2.5 mm, and the thinnest part is 1.2 mm. The thicknesses of the thickest part and thinnest part of the electromagnetic flux control member are not limited to these values ​​as long as the desired characteristics (desired gain) can be obtained and productivity can be maintained.

[0016] 2A , in this embodiment, electromagnetic flux control member 300 has a substantially circular shape in a plan view. Electromagnetic flux control member 300 also has first region 310, second region 320, a plurality of ribs 330 arranged in at least one of first region 310 and second region 320, and gate remnant 341. Each of these will be described below.

[0017] <First Region> As shown in Fig. 1 , first region 310 is a region of communication module 100 that faces primary radiator 200. In the present embodiment, a plurality of ribs 330 for suppressing reflection of electromagnetic waves are arranged in first region 310. When communication module 100 is a transmitting module, first region 310 is a surface that causes electromagnetic waves from primary radiator 200 to enter electromagnetic flux control member 300. On the other hand, when communication module 100 is a receiving module, first region 310 is a surface that causes electromagnetic waves that have entered second region 320 and traveled inside electromagnetic flux control member 300 to exit.

[0018] The shape of first region 310 is not particularly limited and can be appropriately set together with the shape of second region 320 depending on the function required of electromagnetic flux control member 300. Here, the shape of first region 310 refers to the shape when it is assumed that multiple ribs 330 are not arranged in first region 310, even if multiple ribs 330 are arranged in first region 310. The shape of first region 310 may be a convex shape (convex surface), a concave shape (concave surface), or a flat shape (flat surface). In the present embodiment, first region 310 is concave.

[0019] 1 and 2B , second region 320 is a region of electromagnetic flux control member 300 that is located on the opposite side to first region 310. In the present embodiment, second region 320 has a plurality of ribs 330 arranged therein to suppress reflection of electromagnetic waves. When communication module 100 is a transmitting module, second region 320 is a surface that outputs electromagnetic waves that have entered electromagnetic flux control member 300 in first region 310 to the outside. On the other hand, when communication module 100 is a receiving module, second region 320 is a surface that outputs electromagnetic waves from the outside to electromagnetic flux control member 300.

[0020] The shape of second region 320 is not particularly limited and can be appropriately set together with the shape of first region 310 depending on the function required of electromagnetic flux control member 300. Here, the shape of second region 320 refers to the shape when it is assumed that multiple ribs 330 are not arranged in second region 320, even if multiple ribs 330 are arranged in second region 320. The shape of second region 320 may be a convex shape (convex surface), a concave shape (concave surface), or a flat shape (flat surface). In the present embodiment, second region 320 has a convex shape.

[0021] As described above, electromagnetic flux control member 300 has first region 310 and second region 320. First region 310 and second region 320 can be considered to correspond to the lens surfaces of an optical lens. Electromagnetic flux control member 300 having first region 310 and second region 320 can have a plano-convex lens shape, a biconvex lens shape, or a meniscus lens shape. In the present embodiment, first region 310 has a concave shape and second region 320 has a convex shape, so electromagnetic flux control member 300 has a meniscus lens shape.

[0022] <Ribs> The plurality of ribs 330 may be arranged in at least one of the first region 310 and the second region 320. In the present embodiment, the plurality of ribs 330 are arranged in both the first region 310 and the second region 320. The plurality of ribs 330 arranged in the first region 310 are intended to suppress reflection, at the first region 310, of electromagnetic waves incident on the first region 310 or electromagnetic waves emitted from the first region 310. Similarly, the plurality of ribs 330 arranged in the second region 320 are intended to suppress reflection, at the second region 320, of electromagnetic waves incident on the second region 320 or electromagnetic waves emitted from the second region 320. The ribs 330 suppress reflection of electromagnetic waves, thereby improving the gain of transmission and reception of electromagnetic waves.

[0023] The ribs 330 protrude from the first region 310 or the second region 320. In this embodiment, the plurality of ribs 330 arranged in the first region 310 have a generally rectangular parallelepiped shape that curves and extends to fit the concave first region 310. Similarly, in this embodiment, the plurality of ribs 330 arranged in the second region 320 have a generally rectangular parallelepiped shape that curves and extends to fit the convex second region 320. Therefore, in both regions, the cross-sectional shape of the plurality of ribs 330 in a direction perpendicular to the direction in which they extend is generally rectangular (see FIGS. 3B and 3C ).

[0024] 3A to 3C, the direction in which ribs 330 protrude is parallel to the thickness direction (the direction in which electromagnetic waves travel) of electromagnetic flux control member 300. In addition, in the present embodiment, when the electromagnetic flux control member is seen through a plan view, the plurality of ribs 330 in first region 310 and the plurality of ribs 330 in second region 320 substantially overlap. Note that the plurality of ribs 330 in first region 310 and the plurality of ribs 330 in second region 320 do not necessarily have to overlap.

[0025] 3B and 3C, in the present embodiment, in a cross-sectional view perpendicular to the direction in which the ribs 330 extend, the top surfaces of the ribs 330 have a shape different from the curved surface that forms the base of the ribs 330 (the surface when the ribs 330 are assumed to be removed from the first region 310 or the second region 320). Note that in the present embodiment, the top surfaces of the multiple ribs 330 all have the same shape. In the present embodiment, in a cross-sectional view perpendicular to the direction in which the ribs 330 extend, the top surfaces of the ribs 330 have a linear shape that is perpendicular to the thickness direction.

[0026] In this embodiment, there are 32 ribs 330 in each of the first region 310 and the second region 320. The dielectric constant of the material of the electromagnetic flux control member 300 is 11 (refractive index approximately 3.3), and the assumed wavelength of the electromagnetic wave is 1 mm. From the viewpoint of suppressing the reflection of electromagnetic waves of that wavelength while facilitating manufacturing by injection molding, the width of the top of the rib 330 is approximately 0.18 mm, and the width of the valley between two adjacent ribs 330 is approximately 0.12 mm. In this embodiment, in a cross section perpendicular to the rib extension direction, the rib top has a top surface represented by a straight line perpendicular to the thickness direction of the electromagnetic flux control member. The height of the rib is 0.05 mm to 1 mm. Note that the rib height is defined as the distance from the center of the top surface to the curved surface that serves as the base of the rib along the thickness direction of the electromagnetic flux control member, to the point where the straight line intersects with the curved surface of the first region or the second region in the cross section perpendicular to the rib extension direction. Furthermore, when electromagnetic flux control member 300 is viewed from above, the center-to-center distance between multiple ribs 330 (the period of ribs 330) is preferably approximately 0.1 mm to 1 mm. In the present embodiment, the center-to-center distance between multiple ribs 330 (the period of ribs 330) is 0.3 mm.

[0027] These values ​​are optimized based on the wavelength of the electromagnetic waves used and the dielectric constant of the material used in the lens (electromagnetic flux control member). The wavelengths expected for use in the present invention are 0.1 mm to 10 mm, with maximum effectiveness expected for wavelengths of approximately 1 mm to 5 mm. Furthermore, the dielectric constant of the material used is 7 or higher, preferably 10 or higher. A dielectric constant of 7 or higher tends to provide the desired refractive power and necessary gain. Furthermore, when manufacturing using injection molding, materials with a dielectric constant of less than 12 tend to satisfy mechanical properties and be usable. In other words, a dielectric constant of less than 12 is preferred. When using the wavelengths expected for use (1 mm to 5 mm), the width of the peak of the rib 330 is preferably 0.1 mm to 1 mm, the width of the valley between two adjacent ribs is preferably 0.1 mm to 1 mm, and the height of the rib is preferably 0.05 mm to 1 mm. However, these values ​​should not exceed the wavelength used / √(dielectric constant); [√(dielectric constant) = refractive index].

[0028] The plurality of ribs 330 are preferably arranged so as to be substantially parallel to one another when electromagnetic flux control member 300 is viewed in a plan view. Here, "substantially parallel" means that, when electromagnetic flux control member 300 is viewed in a plan view, two straight lines extending along the respective extension directions of two adjacent ribs 330 do not intersect (i.e., are parallel), or the angle formed by these two straight lines is 5° or less. In the present embodiment, the plurality of ribs 330 are arranged so as to be parallel to one another when electromagnetic flux control member 300 is viewed in a plan view.

[0029] From the viewpoint of suppressing reflection of electromagnetic waves, when electromagnetic flux control member 300 is viewed from above, the extending direction of multiple ribs 330 preferably intersects with, and is more preferably perpendicular to, the vibration direction of the electric field of the electromagnetic waves. More specifically, when viewed along the traveling direction of the electromagnetic waves, the angle formed between the extending direction of multiple ribs 330 and the vibration direction of the electric field of the electromagnetic waves is preferably 60° to 120°, and more preferably 75° to 105°, for example.

[0030] In this embodiment, the cross-sectional shape perpendicular to the extending direction of each of the multiple ribs 330 is substantially the same for all cross-sections. To be precise, being substantially the same shape means that the shapes are not completely the same because the curvature of the base curved surface changes.

[0031] From the viewpoint of facilitating manufacturing by injection molding, the plurality of ribs 330 preferably extend in a direction substantially parallel to the inflow direction of material from gate 340 shown in FIG. 4A (described later). Here, "substantially parallel" means that, when electromagnetic flux control member 300 is viewed in a plan view, a line parallel to the inflow direction of material and a line parallel to the extension direction of ribs 330 do not intersect (i.e., are parallel), or the angle formed by these two lines is 5° or less. In the present embodiment, when electromagnetic flux control member 300 is viewed in a plan view, a line parallel to the extension direction of ribs 330 is parallel to a line parallel to the inflow direction of material from gate 340. In addition, in this embodiment, ribs 330 on the convex surface (second region 320) side are connected to peripheral flange 350 over a wider area than the circular second region 320 (as shown in FIG. 2A , when electromagnetic flux control member 300 is viewed in a plan view, ribs 330 on the second region 320 side extend beyond the circular second region 320 and reach a portion of flange 350). This improves manufacturability.

[0032] The direction of material flow from gate 340 can be determined from gate remnant 341 or gate mark 342 shown in Figures 4B and 4C (described later). Specifically, in this embodiment, when electromagnetic flux control member 300 is viewed in a plan view, the direction opposite to the direction in which gate remnant 341 protrudes (shown in Figure 4B (described later)) can be defined as the direction of material flow from the gate. Alternatively, when electromagnetic flux control member 300 is viewed in a plan view, the direction opposite to the direction in which it can be determined that gate 340 would have protruded (shown in Figure 4C (described later)) can be defined as the direction of material flow from gate 340.

[0033] <Gate, Gate Remaining, Gate Trace> Figures 4A to 4C are diagrams for explaining the gate 340, the gate remaining 341, and the gate trace 342. These will be explained below with reference to Figures 4A to 4C.

[0034] Gate 340 corresponds to a path of material that is taken when electromagnetic flux control member 300 is injection molded, and is left in electromagnetic flux control member 300 after molding. Fig. 4A shows a state in which gate 340 remains after electromagnetic flux control member 300 has been injection molded, and Figs. 4B and 4C show electromagnetic flux control member 300 from which gate 340 has been cut. More specifically, Fig. 4B shows gate remainder 341, in which a portion of gate 340 remains in electromagnetic flux control member 300 after gate 340 has been cut, and Fig. 4C shows gate mark 342, which is a cut mark left in electromagnetic flux control member 300 after gate 340 has been cut so that no gate remains in electromagnetic flux control member 300.

[0035] Gate 340 is arranged on a side surface (side gate) of electromagnetic flux control member 300. Specifically, in the present embodiment, gate 340 is arranged on a side surface of flange 350 that exists so as to surround second region 320 when electromagnetic flux control member 300 is viewed in a plan view. In the present embodiment, electromagnetic flux control member 300 has a substantially circular shape in a plan view with notch 351 in flange 350, and gate 340 is arranged in notch 351.

[0036] In this embodiment, gate remainder 341 or gate mark 342 is disposed in notch 351 on the side of flange 350 of electromagnetic flux control member 300 by cutting gate 340 after molding. In this embodiment, electromagnetic flux control member 300 has an outer diameter of φ12 mm. The notch is disposed linearly at a distance of 5.5 mm from the center of electromagnetic flux control member 300. Furthermore, flange 350 has a thickness of 1.2 mm. Considering manufacturability, the flange thickness is preferably 0.5 mm or more. Furthermore, the thickness is preferably ¼ or more of the thickness of the thickest portion of the member. Furthermore, in this embodiment, electromagnetic flux control member 300 may have one notch 351 or multiple notches 351. FIG. 5 shows an example in which electromagnetic flux control member 300 has multiple notches 351. 5 , electromagnetic flux control member 300 has two cutout portions 351 that are arranged facing each other across the center of electromagnetic flux control member 300 when electromagnetic flux control member 300 is viewed in plan view. In Fig. 5 , one of two cutout portions 351 has gate remainder 341, and the other has throwaway tab remainder 343, which is a portion of a throwaway tab (also referred to as a "resin reservoir portion") that remains in electromagnetic flux control member 300 after the throwaway tab is cut off.

[0037] Gate remainder 341, gate mark 342, or notch 351 as described above can be used as a positioning portion for determining the arrangement direction of electromagnetic flux control member 300 so that rib 330 of electromagnetic flux control member 300 intersects with the vibration direction of the electric field of the electromagnetic wave. For example, when manufacturing communication module 100 by arranging electromagnetic flux control member 300 relative to primary radiator 200, the manufacturing device can determine the circumferential (rotational) position of electromagnetic flux control member 300 using gate remainder 341, gate mark 342, or notch 351 as a mark. By incorporating the electromagnetic flux control member of this embodiment into the communication module in this way, it is possible to obtain a higher gain.

[0038] FIG. 6A shows a case where the arrangement direction of rib 330 of electromagnetic flux control member 300 is determined by gate remnant 341 so that it intersects with the vibration direction of the electric field of the electromagnetic wave, and FIG. 6B shows a case where the arrangement direction of electromagnetic flux control member 300 is determined by cutout portion 351 so that it intersects with the vibration direction of the electric field of the electromagnetic wave. As shown in FIGS. 6A and 6B , electromagnetic flux control member 300 has gate remnant 341 or cutout portion 351 and is non-circular in plan view. Taking advantage of the fact that electromagnetic flux control member 300 is non-circular, the arrangement direction can be determined as follows. That is, holding member 300a (e.g., a housing) for holding electromagnetic flux control member 300 is configured to have a non-circular shape in plan view and a recess 300b that fits into electromagnetic flux control member 300. Then, the arrangement direction (particularly the rotational direction) of electromagnetic flux control member 300 can be determined by fitting electromagnetic flux control member 300 into the recess.

[0039] Electromagnetic flux control member 300 may further have a throwaway tab on the opposite side of gate remainder 341, gate mark 342 or notch 351 across the center of electromagnetic flux control member 300 in plan view.

[0040] Electromagnetic flux control member 300 may further have a positioning structure on either side of the center of electromagnetic flux control member 300 in a plan view, opposite gate remnant 341, gate mark 342, or notch 351. The positioning structure is, for example, notch 351, a throwaway tab, a throwaway tab remnant that is a part of the throwaway tab that remains in electromagnetic flux control member 300 after the throwaway tab is cut off, or a throwaway tab mark that is a cutting mark that remains in electromagnetic flux control member 300 after the throwaway tab is cut so that it does not remain in electromagnetic flux control member 300.

[0041] In the present embodiment, it is particularly preferable that electromagnetic flux control member 300 be as follows. That is, electromagnetic flux control member 300 is manufactured by an injection molding process, and in plan view, has a circular shape having cutouts that form chords by cutting out the circle, and gate remains or gate marks of a gate for inflowing resin used in the injection molding process are located in the cutouts. Furthermore, electromagnetic flux control member 300 in plan view has multiple ribs 330 that are arranged in parallel with each other, and the center-to-center distance between multiple ribs 330 is 0.1 mm to 1 mm, and the height of multiple ribs 330 is 0.05 mm to 1 mm, in plan view.

[0042] Simulation A simulation was performed to examine the anti-reflection function of electromagnetic flux control member 300 having a plurality of ribs 330. The simulation used radio waves of 270 GHz radiated from a rectangular waveguide.

[0043] In the simulation of the example, the maximum gain was examined using a communication module having electromagnetic flux control member 300 in which multiple ribs 330 were arranged so as to be perpendicular to the vibration direction of the electric field of the electromagnetic waves of primary radiator 200. On the other hand, as a communication module of comparative example 1, the maximum gain was examined using a communication module having electromagnetic flux control member 300 in which multiple ribs 330 were arranged so as to be parallel to the vibration direction of the electric field of the electromagnetic waves of primary radiator 200. As a communication module of comparative example 2, the maximum gain was examined using a communication module having an electromagnetic flux control member without ribs.

[0044] The maximum gain of the communication module of the example was 24.6 dBi. In contrast, the maximum gain of Comparative Example 1 was 22.7 dBi, and that of Comparative Example 2 was 22.8 dBi. As such, it was found that the maximum gain was large and the reflection of electromagnetic waves was suppressed in the communication module of the example. This is thought to be because, in the communication module of the example, the electromagnetic flux control member was arranged so that multiple ribs were perpendicular to the vibration direction of the electric field of the electromagnetic waves of the primary radiator, thereby suppressing the reflection of electromagnetic waves.

[0045] (Effects) According to the embodiment of the present invention, it is possible to provide an electromagnetic flux control member that has the function of suppressing reflection of electromagnetic waves and that can be easily manufactured by injection molding.

[0046] This application claims priority from Japanese Patent Application No. 2023-151865, filed September 20, 2023. The contents of the specification and drawings of this application are incorporated herein by reference in their entirety.

[0047] The communication module and electromagnetic flux control member according to the present invention are useful for communication using electromagnetic waves.

[0048] REFERENCE SIGNS LIST 100 Communication module 200 Primary radiator 300 Electromagnetic flux control member 300a Holding member 300b Recess 310 First region 320 Second region 330 Rib 340 Gate 341 Gate remainder 342 Gate mark 343 Temporary tab remainder 350 Flange 351 Cutout portion

Claims

1. An electromagnetic flux control member having a first region for inputting electromagnetic waves or for emitting to the outside electromagnetic waves that have traveled inside, and a second region for emitting to the outside the electromagnetic waves inputted in said first region or for inputting electromagnetic waves, wherein the electromagnetic flux control member has a plurality of ribs arranged in at least one of said first region and said second region, and a gate remnant or gate mark on a side of said electromagnetic flux control member, and the plurality of ribs extend in a direction along the flow direction of material from the gate.

2. The electromagnetic flux control member according to claim 1, wherein the electromagnetic flux control member is manufactured by an injection molding process, and when viewed in a plan view, has a circular shape having a cut-out portion such that a chord is formed by cutting out a circle, and a gate residue or gate mark of the gate for inflowing resin used in the injection molding process is located in the cut-out portion.

3. The electromagnetic flux control component according to claim 1, wherein, in a plan view, the multiple ribs are arranged parallel to each other, the center distance between the multiple ribs is 0.1 mm to 1 mm, and the height of the multiple ribs is 0.05 mm to 1 mm.

4. The electromagnetic flux control member according to claim 1, wherein the dielectric constant of the material constituting said electromagnetic flux control member is 7 or more.

5. A communications module comprising: a primary radiator; and an electromagnetic flux control member according to any one of claims 1 to 4, wherein the direction in which the multiple ribs extend intersects with the vibration direction of the electric field of the electromagnetic wave emitted from the primary radiator.

6. A communications module according to claim 5, wherein the gate remains or gate marks are positioning portions for determining the arrangement direction of the electromagnetic flux control member relative to the vibration direction of the electric field of the electromagnetic wave.

7. A communications module comprising: a primary radiator; and an electromagnetic flux control member as described in claim 2, wherein the direction in which the plurality of ribs extend intersects with the vibration direction of the electric field of the electromagnetic wave emitted from the primary radiator, and the cutout portion is a positioning portion for determining the arrangement direction of the electromagnetic flux control member relative to the vibration direction of the electric field of the electromagnetic wave.

8. The communication module according to claim 5, wherein the wavelength of the electromagnetic wave emitted from the primary radiator is from 0.1 mm to 10 mm.

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