Optical module and optical receptacle

Abstract

The invention relates to an optical module and an optical receptacle. This optical module is provided with a light-receiving element, a light-emitting element, an optical transmission body, and an optical receptacle for causing received light from the end surface of the optical transmission body to reach the light-receiving element and causing transmitted light from the light-emitting element to reach the end surface of the optical transmission body. A chief ray of the received light and a chief ray of the transmitted light between the transmissive-reflective portion and the first optical surface are closer in a direction along an optical path between the second optical surface and the transmissive-reflective portion. The first optical surface refracts the received light and the transmitted light such that the received light and the transmitted light approach an extension line of a central axis of the optical transmission body.

Description

Technical Field

[0001] The invention relates to an optical module and an optical socket. Background Art

[0002] An optical socket is known for optically coupling light from an optical transmission body such as an optical fiber to a light receiving element arranged on a substrate, and optically coupling light from a light emitting element arranged on a substrate to the optical transmission body. This method of communicating using light toward the light receiving element and light from the light emitting element through one optical transmission body is called bidirectional communication. In bidirectional communication performed through one optical transmission body, it is not necessary to use an optical transmission body for transmission and an optical transmission body for reception, and the device can be simplified. For example, Patent Document 1 discloses an optical transmission module having an optical component (optical socket) for bidirectional communication performed through one optical transmission body as described above.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2009-251375 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] Figure 1 A cross-sectional schematic diagram of a conventional optical module 1 used for bidirectional communication as described above is shown. The optical module 1 includes a light receiving element 20 and a light emitting element 30 arranged on a substrate 10 , an optical receptacle 40 , and an optical transmission body 50 .

[0008] The bidirectional communication in such an optical module 1 is as follows.

[0009] That is, the reception light from the optical transmission body 50 toward the light receiving element 20 is incident on the inside of the optical socket 40 from the first optical surface 41 of the optical socket 40, is reflected by the transmissive reflective portion 40a, is emitted from the optical socket 40 at the second optical surface 42, and reaches the light receiving element 20. On the other hand, the transmission light from the light emitting element 30 toward the optical transmission body 50 is incident on the inside of the optical socket 40 from the third optical surface 43, is reflected by the reflective portion 44, is refracted and transmitted in the transmissive reflective portion 40a, and is emitted from the optical socket 40 at the first optical surface 41 to reach the end face of the optical transmission body 50.

[0010] Here, it is preferable that the light from the light emitting element 30 stably reaches the light transmission body 50. Therefore, in order to make the light from the light emitting element 30 stably reach the end face of the light transmission body 50, sometimes, as Figure 1As shown, the end face of the optical transmission body 50 is tilted. If the end face of the optical transmission body 50 is tilted in this way, the occurrence of so-called return light, which is the situation where the transmission light from the light emitting element 30 emitted from the first optical surface 41 is reflected at the end face of the optical transmission body 50 and returns to the light emitting element 30, can be suppressed, thereby stabilizing the operation of the light emitting element 30.

[0011] However, the inventors of the present invention have found that if the end face of the optical transmission body 50 is tilted, the following problem will occur. That is, if the end face of the optical transmission body 50 is tilted, light will be refracted at the end face. Specifically, the transmitted light will be refracted when it is incident on the end face of the optical transmission body 50, and the received light will be refracted when it is emitted from the end face of the optical transmission body 50.

[0012] As described above, the inventors of the present invention have found that if the end surface of the optical transmission body 50 is inclined, light will be refracted, and as a result, it will become difficult to align the optical receptacle 40 with respect to the light receiving element 20 and the light emitting element 30 arranged on the substrate 10. Figure 2A , Figure 2B Provide explanation.

[0013] Figure 2A is a graph showing changes in the coupling efficiency of received light and transmitted light caused by positional deviation of the optical receptacle 40 when the end face of the optical transmission body 50 is not inclined. Figure 2B This is a graph showing changes in the coupling efficiency of received light and transmitted light due to positional deviation of optical receptacle 40 when the end surface of optical transmission body 50 is inclined.

[0014] exist Figure 2A , Figure 2B In the figure, the solid line indicates the change in the coupling efficiency of the received light when the optical socket 40 is moved in the Z direction with the center of the second optical surface 42 aligned with the center of the light receiving element 20 as the reference (movement amount 0 μm); the dotted line indicates the change in the coupling efficiency of the transmitted light when the optical socket 40 is moved in the Z direction with the center of the third optical surface 43 aligned with the center of the light emitting element 30 as the reference (movement amount 0 μm). Figure 2A , Figure 2B In FIG. 1 , the coupling efficiency is expressed as a convex curve, but the top of the curve has a substantially linear portion where the coupling efficiency remains almost unchanged even if the moving distance changes.

[0015] This substantially linear portion is related to a positional deviation tolerance range when optical receptacle 40 is aligned with respect to light receiving element 20 and light emitting element 30 disposed on substrate 10 .

[0016] Specifically, from the viewpoint of expanding the positional deviation tolerance range, it is preferable to design optical receptacle 40 so that the substantially straight portion is longer. In addition, from the viewpoint of suppressing the reduction in coupling efficiency even when positional deviation occurs in either of the two directions along the Z axis, it is preferable to design optical receptacle 40 so that the change in coupling efficiency is the same regardless of whether it moves in the + direction or the - direction in the graph. That is, it is preferable that the midpoint of the substantially straight portion (hereinafter also referred to as the tolerance center) is located near the line of the movement amount of 0 μm, and the curve representing the coupling efficiency is bilaterally symmetrical with respect to the line of the movement amount of 0 μm.

[0017] Here, from Figure 2A and Figure 2B As can be seen from the comparison, when the end face of the optical transmission body 50 is not tilted, the tolerance center is close to the line of the movement amount 0 (refer to Figure 2A ), but if the end face of the optical transmission body 50 is tilted, the tolerance center will be away from the line of the movement amount 0 (refer to Figure 2B ). For example, in Figure 2B In the example shown, the light receiving element 20 or the light emitting element 30 is easily affected by the positional deviation in the + direction relative to the optical receptacle 40. If the positional deviation occurs in this direction, the coupling efficiency will be greatly reduced. Figure 2A , Figure 2B This is a diagram for explaining changes in the tolerance range, and the numerical values ​​are hypothetical.

[0018] An object of the present invention is to provide an optical module capable of suppressing the deviation of a tolerance range even when an end face of an optical transmission body is inclined, and an optical receptacle used for the optical module.

[0019] Solutions to the problem

[0020] The present invention relates to the following optical module and optical socket.

[0021] [1] An optical module comprising: a light receiving element; a light emitting element; an optical transmission body; and an optical socket for allowing received light from an end face of the optical transmission body to reach the light receiving element, and for allowing transmitted light from the light emitting element to reach the end face of the optical transmission body, wherein the optical socket comprises: a first optical surface for allowing the received light from the end face of the optical transmission body to enter the interior of the optical socket, and for allowing the transmitted light after passing through the interior of the optical socket to be emitted toward the end face of the optical transmission body; and a second optical surface for allowing the received light after passing through the interior of the optical socket to be emitted toward the light receiving element, or for allowing the transmitted light from the light emitting element to be emitted toward the end face of the optical transmission body. The optical receptacle is provided with a third optical surface, which is arranged at a position farther from the first optical surface than the second optical surface, and is used to make the transmitted light from the light emitting element be incident on the interior of the optical receptacle, or to make the received light after passing through the interior of the optical receptacle be emitted toward the light receiving element; and a transmission and reflection portion, which is used to make the received light incident through the first optical surface be reflected toward the second optical surface and make the transmitted light incident on the interior of the optical receptacle through the third optical surface be transmitted, or make the transmitted light incident on the interior of the optical receptacle through the second optical surface be reflected toward the first optical surface and make the transmitted light incident on the interior of the optical receptacle through the first optical surface be transmitted. The received light is transmitted, in a cross-section containing the central axis of the light transmission body and parallel to the optical axis of the light-emitting element, the end face of the light transmission body opposite to the first optical surface is inclined relative to a surface perpendicular to the central axis of the light transmission body, and compared with a comparative optical module, the main light ray of the received light between the transmission and reflection portion and the first optical surface and the main light ray of the transmitted light are closer in a direction along the following optical path, which is an optical path between the second optical surface and the transmission and reflection portion. The comparative optical module is an optical module constructed in such a way that the optical axis of the light emitted from the first optical surface coincides with the central axis of the light transmission body, and the comparison optical module is an optical module constructed in such a way that the optical axis of the light emitted from the first optical surface coincides with the central axis of the light transmission body. The intersection point of the principal ray of the received light and the first optical surface is set as the first intersection point, the intersection point of the principal ray of the transmitted light and the first optical surface is set as the second intersection point, and when the principal ray of the received light, the principal ray of the transmitted light, the first intersection point and the second intersection point are projected onto the cross-section, the first intersection point and the second intersection point are located in the same area of ​​two areas divided into two by the extension line of the center axis of the optical transmission body, and the first optical surface refracts the principal ray of the received light and the principal ray of the transmitted light in such a way that the principal ray of the received light and the principal ray of the transmitted light are close to the extension line of the center axis of the optical transmission body.

[0022] [2] The optical module according to [1], wherein the cross section includes an optical path between the first optical surface and the transmissive reflector, and an optical path between the second optical surface and the transmissive reflector.

[0023] [3] An optical module as described in [1] or [2], wherein, in the cross-section, the center of the first optical surface is located at a position that does not overlap with the extension line of the central axis of the optical transmission body, and the central axis of the first optical surface is inclined in a manner that the closer it is to the transmissive reflection portion, the closer it is to the extension line of the central axis of the optical transmission body.

[0024] [4] The optical module according to any one of [1] to [3], wherein a principal ray of the received light overlaps a principal ray of the transmitted light between the first optical surface and the transmissive reflector.

[0025] [5] The optical module according to any one of [1] to [4], wherein between the first optical surface and the transmissive reflector, the principal ray of the received light and the principal ray of the transmitted light are parallel to the bottom surface of the optical receptacle.

[0026] [6] An optical module as described in any one of [1] to [5], wherein the main light ray of the received light or the transmitted light between the second optical surface and the light receiving element or the light emitting element, and the main light ray of the transmitted light or the received light between the third optical surface and the light emitting element or the light receiving element are both perpendicular to the bottom surface of the optical socket.

[0027] [7] An optical module as described in any one of [1] to [6], further comprising a reflection portion, which is arranged on the optical path between the third optical surface and the transmission and reflection portion, and is used to reflect the transmitted light from the third optical surface toward the transmission and reflection portion, or to reflect the received light from the transmission and reflection portion toward the third optical surface.

[0028] [8] An optical socket used for the optical module described in any one of [1] to [7].

[0029] Effects of the Invention

[0030] According to the present invention, it is possible to provide an optical module capable of suppressing the deviation of the tolerance range even when the end face of an optical transmission body is inclined, and an optical receptacle used for the optical module. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a diagram showing a conventional (for comparison) optical module;

[0032] Figure 2A , Figure 2B is a graph for illustrating a situation where the tolerance range of an optical socket is biased;

[0033] Figure 3A to Figure 3D is a diagram showing an optical module according to Embodiment 1;

[0034] Figure 4A , Figure 4B is a diagram showing an optical module according to Embodiment 1;

[0035] Figure 5A , Figure 5B is a diagram showing an optical path in an optical module according to Embodiment 1;

[0036] Fig. 6A , Figure 6B is a graph showing simulation results;

[0037] Fig. 7A , Figure 7B is a graph showing simulation results;

[0038] Figures 8A to 8D is a diagram showing an optical module according to Embodiment 2;

[0039] Fig. 9A , Fig. 9B is a diagram showing an optical module according to Embodiment 2;

[0040] FIG. 10A to FIG. 10D is a diagram showing an optical receptacle according to Embodiment 3;

[0041] Fig.11A , Fig. 11B is a diagram showing an optical receptacle according to Embodiment 3;

[0042] FIG. 12A to FIG. 12D is a diagram showing an optical module according to Embodiment 4;

[0043] Fig.13A , Fig. 13B is a diagram showing an optical module according to Embodiment 4;

[0044] FIG. 14A to FIG. 14D is a diagram showing an optical receptacle according to Embodiment 5;

[0045] Fig.15A , Fig. 15B This is a diagram showing an optical receptacle according to a fifth embodiment.

[0046] Description of Reference Numerals

[0047] 1. 100, 100a, 100c, 100d: optical module;

[0048] 10: Substrate;

[0049] 20: light receiving element;

[0050] 30: light emitting element;

[0051] 40, 400, 400a, 400b, 400c, 400d: optical sockets;

[0052] 40a, 450: transmissive reflective portion;

[0053] 41, 410, 410a: first optical surface;

[0054] 42, 420: second optical surface;

[0055] 43, 430: third optical surface;

[0056] 44, 440: reflection part;

[0057] 50, 50a: light transmission body;

[0058] 60, 60a: casing;

[0059] 401b: concave part;

[0060] 401d: slot;

[0061] 402d: cover;

[0062] 410b, 411b: first transmission surface;

[0063] 420b, 421b: second transmission surface;

[0064] 430b, 431b: third transmission surface. DETAILED DESCRIPTION

[0065] [Implementation Method 1]

[0066] [Structure of optical module]

[0067] Hereinafter, an optical module according to Embodiment 1 of the present invention will be described in detail with reference to the drawings.

[0068] Figure 3A is a top view of the optical module 100 according to the first embodiment of the present invention. Figure 3B This is a bottom view. Figure 3C is the main view, Figure 3D It is a side view. Figure 4A So Figure 3C The cross-section diagram taken along line AA of Figure 4B yes Figure 4A A partial enlarged view of . Figure 5A , Figure 5B The diagram is for schematically explaining the optical path in the optical module 100 , and does not represent an actual scale or the like.

[0069] exist Figure 3A to Figure 3D , Figure 4A In the embodiment, the light receiving element, the light emitting element and the light transmitting body are omitted. Figure 4B , Figure 5A , Figure 5BIn FIG. 1 , a light receiving element 20, a light emitting element 30 and a light transmission body 50 are shown, and the optical paths between these are also shown.

[0070] like Figure 3A to Figure 5B As shown, the optical module 100 includes: a light receiving element 20 and a light emitting element 30 disposed on a substrate 10 ; an optical transmission body 50 ; a sleeve 60 ; and an optical receptacle 400 .

[0071] Figure 5A , Figure 5B The light receiving element 20 and the light emitting element 30 are arranged differently on the substrate 10 . Figure 5A The case where the light receiving element 20 is located on the substrate 10 closer to the light transmission body 50 than the light emitting element 30 is is shown. Figure 5B The case where the light emitting element 30 is located on the substrate 10 closer to the light transmission body 50 than the light receiving element 20 is is shown. Figure 5A , Figure 5B The optical paths for bidirectional communication in the illustrated embodiment are respectively as follows.

[0072] That is, in 5A, in a section that includes the central axis CA1 of the optical transmission body and is parallel to the optical axis of the light emitting element 30 (hereinafter, this section is also referred to as a "reference section"), the end face of the optical transmission body 50 that is opposite to the first optical surface 410 is inclined relative to the surface that is perpendicular to the central axis of the optical transmission body 50. As a result, the received light from the end face of the optical transmission body 50 is refracted and emitted. Figure 5A In the example shown, the end face of the optical transmission body 50 is inclined in such a manner that the closer it is to the optical socket 400 (the farther it is from the substrate 10). As a result, the received light is refracted and emitted at the end face of the optical transmission body 50 in a manner that it is directed upward (on the side opposite to the substrate 10) relative to the extension line of the central axis of the optical transmission body 50. The received light emitted in this way is refracted at the first optical surface 410 of the optical socket 400 and is incident on the interior of the optical socket 400, is reflected at the transmission reflection portion 450, and is emitted from the optical socket 400 at the second optical surface 420 to reach the light receiving element 20. It should be noted that in Figure 5A , Figure 5B In the figure, the reference section is a plane parallel to the YZ plane in the XYZ coordinates formed by the mutually orthogonal X-axis, Y-axis, and Z-axis, when the axis parallel to the central axis CA1 of the light transmission body 50 is taken as the Z-axis. In addition, in this specification, the "optical axis of the light emitting element 30" refers to the light ray at the center of the three-dimensional output light beam from the light emitting element 30.

[0073] On the other hand, the transmission light emitted from the light emitting element 30 enters the interior of the optical socket 400 from the third optical surface 430 of the optical socket 400, is reflected by the reflection portion 440, is refracted and transmitted through the transmission reflection portion 450, is refracted by the first optical surface 410, is emitted from the optical socket 400, and reaches the end surface of the optical transmission body 50. At this time, the transmission light is refracted and emitted from the first optical surface 410 in a manner from a position above the extension line of the central axis of the optical transmission body 50 toward one side (lower side) of the extension line of the central axis of the optical transmission body 50.

[0074] exist Figure 5B In the embodiment, the end face of the optical transmission body 50 is also inclined, and the received light from the end face of the optical transmission body 50 is refracted and emitted. As described above, the received light is refracted and emitted in a manner that is directed upward (opposite to the substrate 10) from the extension line of the central axis of the optical transmission body 50 at the end face of the optical transmission body 50. The received light emitted in this way is refracted at the first optical surface 410 of the optical socket 400 and enters the interior of the optical socket 400, refracted and transmitted in the transmissive reflector 450, and reflected at the reflector 440, and then emitted from the optical socket 400 at the third optical surface 430 to reach the light receiving element 20.

[0075] On the other hand, the transmission light emitted from the light emitting element 30 enters the interior of the optical socket 400 from the second optical surface 420, is reflected by the transmissive reflector 450, is refracted at the first optical surface 410, is emitted from the optical socket 400, and reaches the end surface of the optical transmission body 50. At this time, the transmission light is refracted at the first optical surface 410 and emitted in a manner from a position above the extension line of the central axis of the optical transmission body 50 toward one side (lower side) of the extension line of the central axis of the optical transmission body 50.

[0076] Here, in Figure 5A , Figure 5B In the optical module 100 shown in FIG. Figure 1 In contrast, by changing the optical path in the following manner, it is possible to suppress the deviation of the tolerance range.

[0077] That is, according to Figure 5A , Figure 5B and Figure 1 It can be seen that the optical axis of the light emitted from the first optical surface 41 is coincident with the central axis of the optical transmission body 50 in the comparative optical module (see Figure 1 ), the principal ray of the received light and the principal ray of the transmitted light between the transmission and reflection portion 450 and the first optical surface 410 are closer in the direction along the following optical path, which is the optical path between the second optical surface 420 and the transmission and reflection portion 450 (hereinafter, this situation is also referred to as "optical path condition 1").

[0078] The optical path condition 1 can also be expressed as follows. That is, when the principal ray of the received light and the principal ray of the transmitted light between the transmissive reflector 450 and the first optical surface 410 are projected onto the reference cross section, the principal ray of the received light and the principal ray of the transmitted light in the optical module 100 of the present invention are closer in position than the principal ray of the received light and the principal ray of the transmitted light in the comparative optical module 1.

[0079] In addition, according to Figure 5A , Figure 5B It can be seen that when the intersection of the principal ray of the received light and the first optical surface 410 is set as the first intersection point P1, the intersection of the principal ray of the transmitted light and the first optical surface 410 is set as the second intersection point P2, and the principal ray of the received light, the principal ray of the transmitted light, the first intersection point P1 and the second intersection point P2 are projected onto the reference section, the first intersection point P1 and the second intersection point P2 are located in the same area of ​​the two areas divided into two by the extension line of the central axis of the optical transmission body, and the first optical surface 410 refracts the principal ray of the received light and the principal ray of the transmitted light in such a way that the principal ray of the received light and the principal ray of the transmitted light are close to the extension line of the central axis of the optical transmission body (hereinafter, this situation is also referred to as "optical path condition 2"). In addition, in the present embodiment, the reference section includes the optical path between the first optical surface 410 and the transmission and reflection portion 450 and the optical path between the second optical surface 420 and the transmission and reflection portion 450.

[0080] It should be noted that “a case where the projected light is projected onto the reference cross section” includes a case where the principal ray of the received light and the principal ray of the transmitted light exist on the reference cross section.

[0081] In addition, as an example of a case where the main ray of received light and / or the main ray of transmitted light does not exist on the above-mentioned reference cross section, an optical module of embodiment 3 described later can be cited. By satisfying optical path conditions 1 and 2, the deviation of the tolerance range can be suppressed. The details will be described later.

[0082] It should be noted that, more preferably, the arrangement of the main ray of the received light and the main ray of the transmitted light is as follows.

[0083] That is, Figure 5A , Figure 5B As shown, preferably, between the first optical surface 410 and the transmissive reflective portion 450, the principal ray of the received light coincides with the principal ray of the transmitted light. Figure 5A , Figure 5B As shown, preferably, the principal ray of received light and the principal ray of transmitted light between the first optical surface 410 and the transmissive reflector 450 are parallel to the bottom surface of the optical receptacle 400. Thus, the deviation of the tolerance range can be further suppressed.

[0084] Next, each structure of the optical module 100 according to the first embodiment will be described.

[0085] (Substrate)

[0086] The substrate 10 is not particularly limited as long as it can be provided with the light receiving element 20 and the light emitting element 30. Examples of the substrate 10 include a glass composite substrate, a glass epoxy substrate, a flexible substrate, and the like.

[0087] (Light-receiving element and light-emitting element)

[0088] The photoreceiving element 20 is not particularly limited as long as it can receive light (receive light). The photoreceiving element 20 may be one or more. In the present embodiment, there are multiple (for example, 12) photoreceiving elements 20, which are arranged in a row in the X direction. In addition, examples of the photoreceiving element 20 include photodiodes and the like. The light-emitting element 30 is not particularly limited as long as it can emit light (send light). The light-emitting element 30 may be one or more. In the present embodiment, there are multiple (for example, 12) light-emitting elements 30, which are arranged in a row in the X direction. In addition, examples of the light-emitting element 30 include VCSELs and the like.

[0089] It should be noted that not all light receiving elements 20 need to be arranged in a row, and not all light emitting elements 30 need to be arranged in a row. For example, in an optical module 100, four light receiving elements 20 and four light emitting elements 30 can be arranged in a row. Figure 5A As shown in FIG. 1 , the four second optical surfaces 420 and the four third optical surfaces 430 are respectively arranged opposite to each other, and the other four light receiving elements 20 and the other four light emitting elements 30 can be arranged as shown in FIG. Figure 5B As shown in the figure, they are arranged in a manner opposite to the other four third optical surfaces 430 and the other four second optical surfaces 420. That is, the four light receiving elements 20 and the four light emitting elements 30 are arranged in a row in the X direction in a manner opposite to the plurality of second optical surfaces 420, and the other four light emitting elements 30 and the other four light receiving elements 20 are arranged in a row in the X direction in a manner opposite to the plurality of third optical surfaces 430.

[0090] (Light Transmitter)

[0091] There is no particular limitation on the type of the optical transmission body 50. Examples of the type of the optical transmission body 50 include optical fibers and optical waveguides. The optical transmission body 50 can be set to one or more according to the number of the light receiving elements 20 and the light emitting elements 30. In the present embodiment, the number of the optical transmission bodies 50 corresponds to the number of the light receiving elements 20 and the light emitting elements 30, which is a plurality (for example, 12), and the optical transmission bodies 50 are arranged in a row in the X direction. As described above, in the above-mentioned reference section, the end face of the optical transmission body 50 opposite to the first optical surface 410 is inclined relative to the surface perpendicular to the central axis of the optical transmission body 50. Figure 5A , Figure 5B In the example shown, the end surface of optical transmission body 50 is inclined so as to come closer to optical receptacle 400 as it goes upward (gets farther from substrate 10 ).

[0092] (casing)

[0093] The sleeve 60 is a component that holds the end of the optical transmission body 50 and positions the optical transmission body 50 relative to the optical socket 400. In this embodiment, the sleeve 60 is mounted on the optical socket 400 by positioning pins, etc., so that the end surface of the optical transmission body 50 is aligned with the first optical surface 410.

[0094] (Optical socket)

[0095] Next, the structure of optical receptacle 400 included in optical module 100 will be described.

[0096] Optical receptacle 400 has a first optical surface 410 , a second optical surface 420 , a third optical surface 430 , a reflective portion 440 , and a transmissive reflective portion 450 .

[0097] Optical receptacle 400 is formed of a material that is translucent to light of a wavelength used for optical communication (transmitted light and received light). Examples of such a material include transparent resins such as polyetherimide (PEI) and cyclic olefin resin. Optical receptacle 400 is manufactured, for example, by injection molding.

[0098] Next, each component of optical receptacle 400 will be described.

[0099] <First Optical Surface>

[0100] First optical surface 410 is a surface facing the end surface of optical transmission member 50 . First optical surface 410 allows received light from the end surface of optical transmission member 50 to enter optical receptacle 400 , and allows transmitted light passing through optical receptacle 400 to be emitted toward the end surface of optical transmission member 50 .

[0101] In the present embodiment, first optical surface 410 is configured to control received light and transmitted light so as to satisfy the above-described optical path conditions 1 and 2. This can suppress the deviation of the tolerance range of optical receptacle 400 .

[0102] In this embodiment, the first optical surface 410 is a convex lens surface. Figure 5A , Figure 5B As shown, the center C2 is located in a position that does not overlap with the extension line of the central axis CA1 of the optical transmission body 50 in the reference cross section. Figure 5A , Figure 5BIn the example shown, the center C2 of the first optical surface 410 is located above the extension line of the center axis CA1 of the optical transmission body 50 (on the side opposite to the substrate 10). In addition, the center axis CA2 of the first optical surface 410 is inclined so as to be closer to the extension line of the center axis CA1 of the optical transmission body 50 as it approaches the transmissive reflective portion 450.

[0103] <Second Optical Surface>

[0104] The second optical surface 420 is disposed at a position closer to the first optical surface 410 than the third optical surface 430, and is aligned with the light receiving element 20 (see Figure 5A ) or light emitting element 30 (refer to Figure 5B In this embodiment, the second optical surface 420 is a convex lens surface that is convex toward the light receiving element 20 or the light emitting element 30, so that the received light passing through the interior of the optical socket 400 is emitted toward the light receiving element 20 (refer to Figure 5A ), or the transmission light from the light emitting element 30 is incident on the interior of the optical receptacle 400 (refer to Figure 5B In this embodiment, the received light after passing through the interior of the optical receptacle 400 is parallel light, and the second optical surface 420 converges the parallel light and makes it reach the light receiving element 20 (see Figure 5A Alternatively, in the present embodiment, the second optical surface 420 converts the light radially emitted from the light emitting element 30 into parallel light so that the light is incident on the inside of the optical socket 400 (see Figure 5B ).

[0105] <Third optical surface>

[0106] The third optical surface 430 is disposed at a position farther from the first optical surface 410 than the second optical surface 420 and is aligned with the light emitting element 30 (see Figure 5A ) or the light receiving element 20 (refer to Figure 5B In this embodiment, the third optical surface 430 is a convex lens surface that is convex toward the light emitting element 30 or the light receiving element 20, so that the transmission light from the light emitting element 30 is incident on the inside of the optical socket 400 (see Figure 5A ), or emits the received light after passing through the interior of the optical receptacle 400 to the light receiving element 20 (refer to Figure 5B In this embodiment, the third optical surface 430 converts the transmitted light radially emitted from the light emitting element 30 into parallel light so that the transmitted light is incident on the inside of the optical receptacle 400 (see Figure 5A Alternatively, in this embodiment, the received light after passing through the interior of the optical receptacle 400 is parallel light, and the third optical surface 430 converges the parallel light and reaches the light receiving element 20 (see Figure 5B ).

[0107] <Transmissive Reflective Section>

[0108] Transmissive reflector 450 reflects received light incident from first optical surface 410 toward second optical surface 420 and transmits transmitted light incident from third optical surface 430 into optical receptacle 400 (see Figure 5A ), or the transmission light incident from the second optical surface 420 to the interior of the optical receptacle 400 is reflected toward the first optical surface 410, and the reception light incident from the first optical surface 410 is transmitted (refer to Figure 5B The transmissive reflector 450 may reflect one of the received light and the transmitted light having different wavelengths and transmit the other. An example of such a transmissive reflector 450 includes a wavelength separation filter. The wavelength separation filter is made by, for example, performing a multi-layer coating process on glass.

[0109] like Figure 5A , Figure 5B As shown, in this embodiment, transmissive reflector 450 is disposed in a rectangular parallelepiped recess 401b recessed from the top surface of optical receptacle 400. Recess 401b is used to temporarily extract received light and transmitted light to the outside of optical receptacle 400 and allow them to reach transmissive reflector 450 to control the optical path.

[0110] The inner surface of the recess 401b has a transmissive surface. Specifically, the inner surface of the recess 401b has: a first transmissive surface 410b located opposite to the first optical surface 410 ; a second transmissive surface 420b located opposite to the second optical surface 420 ; and a third transmissive surface 430b located opposite to the reflective portion 440 .

[0111] exist Figure 5A In the example shown, the received light incident on the interior of optical receptacle 400 from first optical surface 410 is transmitted through first transmission surface 410b and enters recess 401b, and is reflected by transmission reflection portion 450. The reflected received light is transmitted through second transmission surface 420b and enters the interior of optical receptacle 400, and is emitted from optical receptacle 400 at second optical surface 420.

[0112] On the other hand, the transmission light incident from the third optical surface 430 into the interior of the optical socket 400 is reflected by the reflection portion 440, transmitted through the third transmission surface 430 b and enters the recess 401 b, refracted and transmitted in the transmission reflection portion 450, transmitted through the first transmission surface 410 b and enters the interior of the optical socket 400, and then emitted from the optical socket 400 by the first optical surface 410.

[0113] exist Figure 5BIn the example shown, the received light incident on the interior of optical receptacle 400 from first optical surface 410 transmits through first transmission surface 410b and enters recess 401b, is refracted and transmitted through transmission reflection portion 450, transmits through third transmission surface 430b and enters the interior of optical receptacle 400. The received light entering optical receptacle 400 is reflected by reflection portion 440 and is emitted from optical receptacle 400 by third optical surface 430.

[0114] On the other hand, the transmission light incident on the interior of optical receptacle 400 from second optical surface 420 transmits through second transmission surface 420b and enters recess 401b, is reflected by transmission reflection portion 450, transmits through first transmission surface 410b, and enters the interior of optical receptacle 400. The transmission light entering the interior of optical receptacle 400 is emitted from optical receptacle 400 at first optical surface 410.

[0115] Here, preferably, the above-mentioned Figure 5A , Figure 5B The transmissive reflector 450 is configured in the manner of the optical path conditions 1 and 2 shown in the figure. Specifically, it is preferred that, for example, the optical paths of the received light and the transmitted light be as follows: Figure 5A , Figure 5B The transmissive reflector 450 is configured by appropriately designing the thickness of the transmissive reflector 450 in such a manner as to form the optical path.

[0116] <Reflection section>

[0117] Reflection unit 440 is disposed on the optical path between third optical surface 430 and transmissive reflector 450, and reflects the transmitted light from third optical surface 430 toward transmissive reflector 450 (see Figure 5A ), or reflect the received light from the transmissive reflector 450 toward the third optical surface 430 (refer to Figure 5B ). Reflection portion 440 is not particularly limited as long as it can perform the above-mentioned function. In the present embodiment, reflection portion 440 is a plane (inclined surface) inclined at an angle of 45° with respect to the bottom surface of optical receptacle 400 .

[0118] (simulation)

[0119] Fig. 6A It means that in Figure 5A FIG. 1 is a graph showing changes in the coupling efficiency of received light when the center of light receiving element 20 is moved in the Z direction and the Y direction relative to the center of second optical surface 420 in optical module 100 of Embodiment 1. Fig. 6A In FIG. 1 , the solid line indicates the case of movement in the Z direction, and the dotted line indicates the case of movement in the Y direction.

[0120] Likewise, Figure 6B It means that in Figure 1FIG. 2 is a graph showing changes in the coupling efficiency of received light when the center of light receiving element 20 is moved relative to the center of second optical surface 42 in the Z direction and the Y direction in optical module 1 of the comparative example shown. Figure 6B In FIG. 1 , the solid line indicates the case of movement in the Z direction, and the dotted line indicates the case of movement in the Y direction.

[0121] on the other hand, Fig. 7A It means that in Figure 5A FIG. 1 is a graph showing changes in the coupling efficiency of transmitted light when the center of light emitting element 30 is moved relative to the center of third optical surface 430 in the Z direction and the Y direction in optical module 100 of Embodiment 1. Fig. 7A In FIG. 1 , the solid line indicates the case of movement in the Z direction, and the dotted line indicates the case of movement in the Y direction.

[0122] Likewise, Figure 7B It means that in Figure 1 FIG. 4 is a graph showing changes in the coupling efficiency of received light when the center of light emitting element 30 is moved relative to the center of third optical surface 430 in the Z direction and the Y direction in optical module 1 of the comparative example shown. Figure 7B In FIG. 1 , the solid line indicates the case of movement in the Z direction, and the dotted line indicates the case of movement in the Y direction.

[0123] exist Fig. 6A , Figure 6B In FIG. 1 , the point where the movement amount is 0 μm indicates that the center of the light receiving element 20 and the center of the second optical surface 420 coincide with each other when viewed from the Y direction. Fig. 7A , Figure 7B In FIG. 1 , a point where the movement amount is 0 μm indicates that the center of light emitting element 30 coincides with the center of the third optical surface when viewed from the Y direction.

[0124] according to Fig. 6A and Figure 6B Comparison and Fig. 7A and Figure 7B It can be seen from the comparison that in the optical module 100 of the present embodiment, the line with a movement amount of 0 μm and the center of the straight line portion where the coupling efficiency does not change (the tolerance center) are closer than those in the optical module 1 of the comparative example. That is, in the optical module 100 of the present embodiment, the bias of the tolerance range is suppressed. Specifically, Figures 6A to 7B In the example shown, the bias of the tolerance range (vulnerability to positional deviation in the + direction) is suppressed, which is a situation where the coupling efficiency drops sharply when the light receiving element 20 and the light emitting element 30 are moved a certain distance in the + direction. This is because Figure 1 In comparison, the optical module 100 is Figure 5A As shown, optical path conditions 1 and 2 are met.

[0125] (Effect)

[0126] According to the optical module 100 of the present embodiment, by satisfying the optical path conditions 1 and 2, the deviation of the tolerance range is suppressed.

[0127] [Other embodiments]

[0128] Next, embodiments 2 to 5 that satisfy optical path conditions 1 and 2 similarly to embodiment 1 will be described. Embodiments 2 to 5 will be described mainly in terms of differences from embodiment 1. In embodiments 2 to 5, the same components as those of embodiment 1 are denoted by the same reference numerals and description thereof will be omitted.

[0129] [Implementation Method 2]

[0130] Fig. 8A is a top view of an optical module 100a according to Embodiment 2 of the present invention. Figure 8B This is a bottom view. Figure 8C is the main view, Fig.8D It is a side view. Fig. 9A is along Figure 8C The cross-section diagram of line AA, Fig. 9B yes Fig. 9A A partial enlarged view of .

[0131] In the optical module 100a, the inclination direction of the end surface of the optical transmission body 50a is different from that of the optical module 100 of Embodiment 1. Accordingly, in the optical module 100a, the position and inclination direction of the first optical surface 410a are different from those of Embodiment 1. Specifically, Fig. 9B As shown in FIG. 1 , in the optical module 100a, the end surface of the optical transmission body 50a is inclined so as to be closer to the optical receptacle 400a as it is directed downward (closer to the substrate 10). As a result, the received light is refracted and emitted at the end surface of the optical transmission body 50a in a manner that it is directed downward (toward the substrate 10) relative to the extension line of the central axis CA1 of the optical transmission body 50a (compare and refer to FIG. 1 ). Fig. 9B and Figure 4B ). In the present embodiment, the center of the first optical surface 410a is located on the lower side (substrate 10 side) than the extension line of the center axis CA1 of the optical transmission body 50a. In addition, the center axis of the first optical surface 410a is inclined in a manner that the closer it is to the transmissive reflector 450, the closer it is to the extension line of the center axis CA1 of the optical transmission body 50a. In this way, the optical socket 400a of the optical module 100a only needs to be configured to satisfy optical path conditions 1 and 2 with respect to the received light refracted downward at the end face of the optical transmission body 50a. That is, as Fig. 9BAs shown, in the optical module 100a, in the cross section including the optical path, the lower area of ​​the two areas divided into two by the extension line of the central axis CA1 of the optical transmission body 50 satisfies the optical path conditions 1 and 2. It should be noted that in the first embodiment, the upper area of ​​the two areas divided into two satisfies the optical path conditions 1 and 2. Therefore, the second embodiment suppresses the bias of the tolerance range in the same way as the first embodiment (compare and refer to Fig. 9B and Figure 4B ).

[0132] (Effect)

[0133] The optical module 100 a according to the second embodiment has the same effects as the optical module 100 according to the first embodiment.

[0134] [Implementation method 3]

[0135] Fig. 10A 4 is a top view of optical receptacle 400b according to Embodiment 3 of the present invention. Fig. 10B This is a bottom view. Fig. 10C is the main view, Fig. 10D It is a side view. Fig.11A So Fig. 10C The cross-section diagram taken along line AA of Fig. 11B yes Fig.11A A partial enlarged view of .

[0136] Recess 401b included in optical receptacle 400b differs from recess 401b included in Embodiment 1 in that recess 401b has a structure for suppressing return light. Recess 401b will be described below.

[0137] like Fig. 11B As shown, the concave portion 401b has a first transmissive surface 411b, a second transmissive surface 421b and a third transmissive surface 431b. Fig. 10A As shown, in the concave portion 401b, the first transmission surface 411b and the second transmission surface 421b are inclined relative to a vertical plane perpendicular to the central axis CA1 of the optical transmission body 50. Specifically, as shown in FIG. Fig. 10AAs shown, in the present embodiment, when looking down at the optical socket 400b, the first transmission surface 411b is inclined in such a manner that one end thereof is closer to the front face of the optical socket 400b, while the other end thereof is farther away from the front face of the optical socket 400b. Similarly, the second transmission surface 421b is inclined in such a manner that one end thereof is closer to the front face of the optical socket 400b, while the other end thereof is farther away from the front face of the optical socket 400b. It should be noted that, in the present embodiment, the first transmission surface 411b and the second transmission surface 421b are parallel. Thus, since the first transmission surface 411b and the second transmission surface 421b are inclined, the received light and the transmitted light will not be transmitted vertically through the first transmission surface 411b and the second transmission surface 421b. Specifically, in Embodiment 3, the received light and the transmitted light after transmitting through the first transmission surface 411b and / or the second transmission surface 421b are refracted in such a manner as to be away from the above-mentioned reference section or to be close to the above-mentioned reference section (towards Figure 5A , Figure 5B refraction in the X direction).

[0138] Thus, so-called return light, in which the received light and the transmitted light are reflected on the first transmission surface 411b and the second transmission surface 421b and return, is suppressed. From the viewpoint of suppressing the return light, the tilt angle may be appropriately set.

[0139] (Effect)

[0140] Optical receptacle 400b according to Embodiment 3 has the effect of suppressing the deviation of the tolerance range similarly to Embodiment 1. In addition, optical receptacle 400b according to Embodiment 3 has the effect of suppressing the return light.

[0141] [Implementation Method 4]

[0142] Fig. 12A is a top view of an optical module 100c according to a fourth embodiment of the present invention. Fig. 12B This is a bottom view. Fig. 12C is the main view, Fig.12D It is a side view. Fig.13A So Fig. 12C The cross-section diagram taken along line AA of Fig. 13B yes Fig.13A A partial enlarged view of .

[0143] The optical module 100c of the fourth embodiment includes an optical receptacle 400c. Fig.13A As shown, optical receptacle 400c differs from optical receptacle 400 in Embodiment 1 in that it has no reflecting portion and has third optical surface 430 on the back surface of optical receptacle 400c.

[0144] like Fig. 13BAs shown, in the optical module 100c of the fourth embodiment, when the third optical surface 430 is opposite to the light receiving element 20, the received light from the optical transmission body 50 is incident on the inside of the optical receptacle 400c from the first optical surface 410, is transmitted through the transmissive reflector 450, and is emitted from the third optical surface 430 to the light receiving element 20. On the other hand, when the third optical surface 430 is opposite to the light emitting element 30, the transmitted light from the light emitting element 30 is incident on the third optical surface 430, is transmitted through the transmissive reflector 450, and is emitted from the first optical surface 410 to the end surface of the optical transmission body 50.

[0145] (Effect)

[0146] The optical module 100 c according to the fourth embodiment has the effect of suppressing the deviation of the tolerance range similarly to the first embodiment.

[0147] [Implementation method 5]

[0148] Fig.14A 4 is a top view of optical receptacle 400d according to Embodiment 5 of the present invention. Fig. 14B This is a bottom view. Fig. 14C is the rear view, Fig.14D It is a side view. Fig.15A So Fig. 14C Cross-section view taken along line AA. Fig. 15B yes Fig.15A A partial enlarged view of .

[0149] The optical socket 400d is different from the optical socket 400 of the first embodiment in that it has a groove 401d for holding the optical transmission body 50 instead of the sleeve 60. In this embodiment, there are a plurality of grooves 401d extending from the front side to the back side of the optical socket 400d. Fig. 15B As shown, the optical transmission member 50 disposed in the groove 401d is pressed by the cover 402d.

[0150] (Effect)

[0151] The optical module 100d of the fifth embodiment has the effect of suppressing the deviation of the tolerance range similarly to the first embodiment. In the optical module 100d of the fifth embodiment, the optical transmission member 50 can be held by the groove 401d.

[0152] Industrial Applicability

[0153] The optical module and the optical receptacle of the present invention are useful for optical communications using an optical transmission element, for example.

Claims

1. An optical module, comprising: Light receiving element; Light emitting element; Light transmission body; as well as an optical socket for allowing the received light from the end face of the optical transmission body to reach the light receiving element and for allowing the transmitted light from the light emitting element to reach the end face of the optical transmission body, The optical module is characterized in that: The optical socket has: a first optical surface for causing the received light from the end surface of the optical transmission body to be incident on the interior of the optical socket, and causing the transmitted light after passing through the interior of the optical socket to be emitted toward the end surface of the optical transmission body; a second optical surface for causing the received light passing through the interior of the optical socket to be emitted toward the light receiving element, or causing the transmitted light from the light emitting element to be incident on the interior of the optical socket; a third optical surface, arranged at a position farther from the first optical surface than the second optical surface, for allowing the transmitted light from the light emitting element to be incident on the inside of the optical socket, or for allowing the received light passing through the inside of the optical socket to be emitted toward the light receiving element; as well as a transmissive reflector for reflecting the received light incident through the first optical surface toward the second optical surface and transmitting the transmitted light incident through the third optical surface to the interior of the optical socket, or reflecting the transmitted light incident through the second optical surface to the first optical surface and transmitting the received light incident through the first optical surface to the interior of the optical socket, In a cross section including the central axis of the optical transmission body and parallel to the optical axis of the light emitting element, an end face of the optical transmission body facing the first optical surface is inclined relative to a surface perpendicular to the central axis of the optical transmission body. Compared to a comparative optical module, the principal ray of the received light and the principal ray of the transmitted light between the transmissive reflector and the first optical surface are closer in a direction along the optical path between the second optical surface and the transmissive reflector, and the comparative optical module is an optical module configured in such a way that the optical axis of the light emitted from the first optical surface coincides with the central axis of the optical transmission body, When the intersection of the principal ray of the received light and the first optical surface is set as the first intersection, the intersection of the principal ray of the transmitted light and the first optical surface is set as the second intersection, and the principal ray of the received light, the principal ray of the transmitted light, the first intersection and the second intersection are projected onto the cross-section, the first intersection and the second intersection are located in the same area of ​​two areas divided into two by the extension line of the center axis of the optical transmission body, and the first optical surface refracts the principal ray of the received light and the principal ray of the transmitted light in such a way that the principal ray of the received light and the principal ray of the transmitted light approach the extension line of the center axis of the optical transmission body.

2. The optical module according to claim 1, wherein: The cross section includes an optical path between the first optical surface and the transmissive reflective portion, and an optical path between the second optical surface and the transmissive reflective portion.

3. The optical module according to claim 1, wherein: In the cross section, the center of the first optical surface is located at a position that does not overlap with an extension line of the central axis of the optical transmission body. The central axis of the first optical surface is inclined so as to be closer to an extension line of the central axis of the light transmission body as it approaches the transmissive reflective portion.

4. The optical module according to claim 1, wherein: Between the first optical surface and the transmissive reflective portion, a principal ray of the received light overlaps with a principal ray of the transmitted light.

5. The optical module according to claim 1, wherein: Between the first optical surface and the transmissive reflector, the principal ray of the received light and the principal ray of the transmitted light are parallel to the bottom surface of the optical receptacle.

6. The optical module according to claim 1, wherein: The main ray of the received light or the transmitted light between the second optical surface and the light receiving element or the light emitting element, and the main ray of the transmitted light or the received light between the third optical surface and the light emitting element or the light receiving element are both perpendicular to the bottom surface of the optical socket.

7. The optical module according to claim 1, wherein: A reflecting portion is further provided, which is arranged on an optical path between the third optical surface and the transmissive reflecting portion and is used to reflect the transmitted light from the third optical surface toward the transmissive reflecting portion or to reflect the received light from the transmissive reflecting portion toward the third optical surface.

8. An optical socket, characterized in that: Used in the optical module according to any one of claims 1 to 7.

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