Optical Receptacles and Optical Modules

Abstract

To provide an optical receptacle capable of suppressing a decrease in accuracy of an optical surface position in spite of ambient temperature change.SOLUTION: An optical receptacle 140 comprises: an optical receptacle body 120 that has a first optical surface 121 for making light which is emitted from a photoelectric conversion element package 110, incident on inside of the optical receptacle 140 or for making light which has advanced through inside of the optical receptacle 140, emitted toward the photoelectric conversion element package 110, and a second optical surface 122 for making the light which has advanced through the inside of the optical receptacle 140, emitted toward the optical transmission body 150 or for making the light which is emitted from the optical transmission body 150, incident on the inside of the optical receptacle 140; and a deformation restraining member 130 that is configured to surround the optical receptacle body 120 and is made of a material having a linear expansion coefficient smaller than that of the optical receptacle body 120.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an optical receptacle and an optical module. [Background technology]

[0002] Optical modules equipped with a light-emitting element such as a surface-emitting laser (for example, a vertical cavity surface-emitting laser (VCSEL)) and a light-receiving element such as a photodetector have been used for optical communications using optical transmission bodies such as optical fibers and optical waveguides. An optical module has one or more photoelectric conversion elements (light-emitting elements or light-receiving elements) and an optical receptacle for transmission, reception, or transmission and reception.

[0003] Patent Document 1 describes a resin lens structure (optical receptacle) including an objective surface (first optical surface) and an image surface (second optical surface). In the lens structure described in Patent Document 1, a light source or a photodetector is fixed to the lens structure so as to face the objective surface, and an optical fiber is fixed to the lens structure so as to face the image surface. The lens structure described in Patent Document 1 guides light emitted from the light source to an end face of the optical fiber, and guides light emitted from the optical fiber to the photodetector. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-163372 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, the lens structure described in Patent Document 1 is used in the field of optical communication. Therefore, it is expected that the lens structure will be used in a high-temperature environment or a low-temperature environment. However, since the lens structure described in Patent Document 1 is made of resin, it expands in a high-temperature environment and contracts in a low-temperature environment. In this way, the lens structure expands or contracts, and the positional accuracy of the light source or the light detection device relative to the lens structure cannot be maintained, the optical coupling efficiency decreases, and there is a risk that optical communication cannot be performed appropriately. Similarly, the positional accuracy of the optical fiber relative to the lens structure cannot be maintained, and the optical coupling efficiency decreases, and there is a risk that optical communication cannot be performed appropriately.

[0006] An object of the present invention is to provide an optical receptacle that can suppress deterioration in the positional accuracy of an optical surface regardless of changes in the ambient temperature. Another object of the present invention is to provide an optical module having the optical receptacle. [Means for solving the problem]

[0007] An optical receptacle according to one embodiment of the present invention is an optical receptacle for optically coupling a photoelectric conversion element and an optical transmission body when disposed between the photoelectric conversion element package including the photoelectric conversion element and the optical transmission body, the optical receptacle having an optical receptacle body and a deformation suppressing member configured to surround the optical receptacle body and made of a material having a smaller linear expansion coefficient than the optical receptacle body, the optical receptacle body causing light emitted from the photoelectric conversion element package to enter the interior of the optical receptacle body. and a second optical surface for emitting light that has traveled inside the optical receptacle body toward the optical transmission body or for causing light emitted from the optical transmission body to enter the inside of the optical receptacle body, wherein at least a portion of the optical path between the first optical surface and the second optical surface is surrounded by the deformation suppression member, and the deformation suppression member is joined to the optical receptacle body.

[0008] An optical module according to one embodiment of the present invention includes a photoelectric conversion element package including a photoelectric conversion element, and the above-described optical receptacle for optically coupling the photoelectric conversion element and an optical transmission body. Effect of the Invention

[0009] According to the present invention, it is possible to provide an optical receptacle that can suppress deterioration in the positional accuracy of the optical surface even if the temperature around the optical receptacle changes. Also, according to the present invention, it is possible to provide an optical module that includes this optical receptacle. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1A is a cross-sectional view of an optical module according to embodiment 1, and FIGS. 1B and 1C are diagrams for explaining how positional deviation of an optical surface due to temperature change is suppressed in the optical module according to embodiment 1. [Diagram 2] FIG. 2 is a cross-sectional view of the optical module according to the second embodiment. [Diagram 3] FIG. 3A is a cross-sectional view of an optical module according to a third embodiment, and FIG. 3B is a cross-sectional view of an optical module according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Optical modules and optical receptacles according to embodiments of the present invention will be described in detail below with reference to the drawings.

[0012] [Embodiment 1] (Optical module configuration) 1A is a cross-sectional view showing optical module 100 having photoelectric conversion element package 110 including photoelectric conversion element 112, and optical receptacle 140 for optically coupling photoelectric conversion element 112 and optical transmission body 150. This cross-sectional view is a cross-sectional view including first central axis CA1 of first optical surface 121 and second central axis CA2 of second optical surface 122, which will be described later.

[0013] 1A, optical module 100 includes photoelectric conversion element package 110 and optical receptacle 140. In optical module 100, photoelectric conversion element 112 of photoelectric conversion element package 110 and optical transmission body 150 are optically coupled by optical receptacle 140.

[0014] Optical module 100 may be an optical module for transmission or an optical module for reception. When optical module 100 is an optical module for transmission, optical receptacle 140 guides light emitted from photoelectric conversion element package 110 to an end face of optical transmission body 150. When optical module 100 is an optical module for reception, optical receptacle 140 guides light emitted from an end face of optical transmission body 150 to photoelectric conversion element package 110.

[0015] Photoelectric conversion element package 110 includes housing 111, photoelectric conversion element 112, and leads 113. Photoelectric conversion element 112 is disposed inside housing 111. Photoelectric conversion element package 110 is fixed to optical receptacle 140. In the present embodiment, photoelectric conversion element package 110 is fixed to optical receptacle 140 such that a portion of photoelectric conversion element package 110 is housed in cylindrical portion 126. More specifically, in the present embodiment, photoelectric conversion element package 110 is fixed to cylindrical portion 126 via adhesive 10.

[0016] The photoelectric conversion element 112 is a light emitting element 114 or a light receiving element 115, and is disposed inside the housing 111. When the optical module 100 is an optical module for transmission, the photoelectric conversion element 112 is a light emitting element 114. When the optical module 100 is an optical module for reception, the photoelectric conversion element 112 is a light receiving element 115. The light emitting element 114 is, for example, a vertical cavity surface emitting laser (VCSEL). The light receiving element 115 is, for example, a photodetector.

[0017] One end of the lead 113 is connected to the photoelectric conversion element 112. The lead 113 is arranged so as to protrude from the bottom surface of the housing 111. The number of the leads 113 is not particularly limited. In the present embodiment, the number of the leads 113 is three. Furthermore, in the present embodiment, the three leads 113 are arranged so as to be equally spaced in the circumferential direction when the photoelectric conversion element package 110 is viewed from the bottom.

[0018] When optical receptacle 140 is disposed between photoelectric conversion element package 110 and optical transmission body 150, it optically couples photoelectric conversion element package 110 including light emitting element 114 or light receiving element 115 to an end face of optical transmission body 150. When optical module 100 is a transmitting optical module 100, optical receptacle 140 receives light emitted from photoelectric conversion element 112, which is light emitting element 114, and outputs the received light toward an end face of optical transmission body 150. When optical module 100 is a receiving optical module 100, optical receptacle 140 receives light emitted from an end face of optical transmission body 150, and outputs the light toward a light receiving surface of photoelectric conversion element 112, which is light receiving element 115.

[0019] The type of the optical transmission body 150 is not particularly limited. Examples of the type of the optical transmission body 150 include an optical fiber and an optical waveguide. In this embodiment, the optical transmission body 150 is an optical fiber. The optical fiber may be a single mode type or a multimode type. In this embodiment, the optical transmission body 150 is accommodated inside the ferrule 151, and the optical transmission body 150 is connected to the optical receptacle 140 via the ferrule 151. The ferrule 151 is a substantially cylindrical member configured to surround the optical transmission body 150. The ferrule 151 is accommodated in a ferrule accommodating portion 129 of the optical receptacle 140 described later with the optical transmission body 150 accommodated therein.

[0020] (Optical receptacle configuration) As shown in FIG. 1A, optical receptacle 140 has optical receptacle body 120 and deformation suppressing member 130.

[0021] Optical receptacle body 120 has first optical surface 121, second optical surface 122, cylindrical portion 126, and ferrule receiving portion 129.

[0022] Optical receptacle body 120 is a substantially cylindrical optical member. In the present embodiment, photoelectric conversion element package 110 is fixed to one end of optical receptacle body 120 via cylindrical portion 126, and ferrule 151 housing optical transmission body 150 is fixed to the other end via ferrule housing portion 129.

[0023] Optical receptacle 140 is formed using a material that is translucent to light of a wavelength used in optical communication. Examples of materials for optical receptacle 140 include transparent resins such as polyetherimide (PEI) such as Ultem (registered trademark) and cyclic olefin resin. Optical receptacle 140 can be manufactured by integral molding, for example, by injection molding.

[0024] First optical surface 121 is an optical surface for allowing light emitted from photoelectric conversion element package 110 (light-emitting element 114) to enter inside optical receptacle 140, or for allowing light that enters second optical surface 122 and travels inside optical receptacle 140 to exit toward photoelectric conversion element package 110 (light-receiving element 115). The shape of first optical surface 121 is not particularly limited. First optical surface 121 may be a convex lens surface that is convex toward photoelectric conversion element package 110, a concave lens surface that is concave toward photoelectric conversion element package 110, or a flat surface. In this embodiment, first optical surface 121 is a convex lens surface that is convex toward photoelectric conversion element package 110. The shape of first optical surface 121 in plan view is not particularly limited. The shape of first optical surface 121 in plan view may be a circular shape or an elliptical shape. In this embodiment, the shape of first optical surface 121 in plan view is a circular shape.

[0025] The first central axis CA1 of the first optical surface 121 may or may not be perpendicular to the surface of the photoelectric conversion element 112 (the light emitting surface of the light emitting element 114). In this embodiment, the first central axis CA1 is perpendicular to the surface of the photoelectric conversion element 112 (the light emitting surface of the light emitting element 114). In addition, it is preferable that the first central axis CA1 of the first optical surface 121 coincides with the center of the surface of the photoelectric conversion element package 110 (the light emitting surface of the light emitting element 114).

[0026] The cylindrical portion 126 is disposed so as to surround the first optical surface 121. The cylindrical portion 126 accommodates at least a portion of the photoelectric conversion element package 110 such that the first optical surface 121 faces the photoelectric conversion element 112. In the present embodiment, the cylindrical portion 126 and the photoelectric conversion element package 110 are joined with an adhesive 10.

[0027] In this embodiment, the cross-sectional shape of first optical surface 121 of cylindrical portion 126 perpendicular to first central axis CA1 is ring-shaped.

[0028] Second optical surface 122 is an optical surface for emitting light that has entered first optical surface 121 and traveled inside optical receptacle 140 toward the end face of optical transmission body 150, or for allowing light emitted from the end face of optical transmission body 150 to enter the inside of optical receptacle 140. The shape of second optical surface 122 is not particularly limited. Second optical surface 122 may be a convex lens surface that is convex toward optical transmission body 150, a concave lens surface that is concave toward optical transmission body 150, or a flat surface. In this embodiment, second optical surface 122 is a flat surface. The planar shape of second optical surface 122 is not particularly limited. The planar shape of second optical surface 122 may be a circular shape or an elliptical shape. In this embodiment, the planar shape of second optical surface 122 is a circular shape.

[0029] The second central axis CA2 of the second optical surface 122 may or may not be perpendicular to the end face of the optical transmission body 150. In the present embodiment, the second central axis CA2 is perpendicular to the end face of the optical transmission body 150. It is preferable that the second central axis CA2 of the second optical surface 122 coincides with the center of the end face of the optical transmission body 150.

[0030] The ferrule accommodating portion 129 accommodates the ferrule 151. By accommodating the ferrule 151 in the ferrule accommodating portion 129, the end of the optical transmission body 150 and the second optical surface 122 are disposed at a position facing each other. The ferrule accommodating portion 129 may have any shape that is complementary to the ferrule 151. In the present embodiment, since the ferrule 151 is cylindrical, the ferrule accommodating portion 129 is cylindrical including a space capable of accommodating the ferrule 151.

[0031] Deformation suppressing member 130 is configured to surround optical receptacle body 120 and is joined to optical receptacle body 120. In the present embodiment, deformation suppressing member 130 is an annular member and is joined to optical receptacle body 120 by, for example, adhesion, welding, or the like. In the present embodiment, deformation suppressing member 130 is joined so as to follow tubular portion 126 of optical receptacle body 120. Deformation suppressing member 130 is disposed so as to surround at least a part of the optical path between first optical surface 121 and second optical surface 122. In the present embodiment, the entire optical path between first optical surface 121 and second optical surface 122 is surrounded by deformation suppressing member 130. In order to increase the joining strength, an uneven shape may be disposed on the outer periphery of optical receptacle body 120 (including the outer periphery of tubular portion 126), which is the joining surface with deformation suppressing member 130.

[0032] Deformation suppressing member 130 is made of a material having a smaller linear expansion coefficient than optical receptacle body 120. Examples of materials having a smaller linear expansion coefficient than optical receptacle body 120 include metal and resin. When deformation suppressing member 130 has the above-described configuration, optical receptacle body 120 is suppressed from expanding or contracting due to temperature change, and the position of first optical surface 121 is suppressed from shifting relative to photoelectric conversion element 112 of photoelectric conversion element package 110.

[0033] The end of the deformation suppressing member 130 on the optical transmission body 150 side is preferably located closer to the second optical surface 122 than the edge of the first optical surface 121. Moreover, it is more preferable that the end of the deformation suppressing member 130 on the optical transmission body 150 side is closer to the optical transmission body 150 than the second optical surface 122. Moreover, it is preferable that the end of the deformation suppressing member 130 on the photoelectric conversion element package 110 side is located closer to the photoelectric conversion element package 110 than the top of the first optical surface 121. By positioning the two ends of the deformation suppressing member 130 as described above, the deformation suppressing member 130 is positioned so as to surround the first optical surface 121, which makes it easier to more reliably suppress positional deviation of the first optical surface 121.

[0034] (Suppression of misalignment of optical surfaces at high and low temperatures) 1B and 1C are diagrams for explaining how deformation suppressing member 130 suppresses the occurrence of positional shifts of the center of first optical surface 121 at high and low temperatures, respectively.

[0035] As shown in FIG. 1B, at high temperatures, the expansion of optical receptacle body 120 causes forces to act on first optical surface 121 and second optical surface 122 in directions away from first central axis CA1 of first optical surface 121 and second central axis CA2 of second optical surface 122. However, the presence of deformation suppression member 130 suppresses the expansion of optical receptacle body 120.

[0036] On the other hand, as shown in FIG. 1C, at low temperatures, due to the contraction of optical receptacle body 120, forces act on first optical surface 121 and second optical surface 122 in directions toward first central axis CA1 and second central axis CA2 of first optical surface 121. However, the presence of deformation suppression member 130 suppresses the contraction of optical receptacle body 120.

[0037] As described above, deformation suppressing member 130 suppresses the occurrence of positional shifts of the center of first optical surface 121 at high and low temperatures.

[0038] (effect) According to the optical receptacle according to the first embodiment, even if the temperature around the optical receptacle changes, it is possible to suppress misalignment of the first optical surface and suppress a decrease in optical coupling efficiency.

[0039] [Embodiment 2] 2 is a diagram showing optical module 200 according to embodiment 2. Optical module 200 according to embodiment 2 differs from optical module 100 according to embodiment 1 in that optical receptacle 240 does not have cylindrical portion 126. In addition, optical module according to embodiment 2 differs from optical module 100 according to embodiment 1 in that one end of deformation suppressing member 230 is configured to surround optical receptacle body 220, and the other end is configured to accommodate at least a part of photoelectric conversion element package 110 such that first optical surface 121 and photoelectric conversion element 112 face each other.

[0040] Deformation suppressing member 230 may be one part or two parts. When deformation suppressing member 230 is two parts, deformation suppressing member 230 is composed of a first deformation suppressing member and a second deformation suppressing member, where the first deformation suppressing member is configured to surround optical receptacle body 220, and the second deformation suppressing member is configured to accommodate at least a part of photoelectric conversion element package 110 such that first optical surface 121 and photoelectric conversion element 112 face each other. Note that an end of the first deformation suppressing member on the first optical surface 121 side and an end of the second deformation suppressing member on the first optical surface 121 side may be joined by, for example, welding.

[0041] In the optical module 200 according to the second embodiment, the same members as those in the optical module 100 according to the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

[0042] Deformation suppressing member 230 may be joined to optical receptacle body 220 by adhesion, welding, or the like. In the present embodiment, deformation suppressing member 230 is adhered to optical receptacle body 220 by adhesive 10.

[0043] The deformation suppressing member 230 may have the following configuration similar to that of the deformation suppressing member 130, except that it is configured to accommodate at least a portion of the photoelectric conversion element package 110.

[0044] That is, deformation suppressing member 230 is configured to surround optical receptacle body 220, and may be made of a material having a smaller linear expansion coefficient than optical receptacle body 220. Furthermore, at least a portion of the optical path between first optical surface 121 and second optical surface 122 may be surrounded by deformation suppressing member 230.

[0045] Moreover, one end of the deformation suppressing member 230 is preferably located closer to the second optical surface 122 than the edge of the first optical surface 121 .

[0046] (effect) According to the optical receptacle according to the second embodiment, even if the temperature around the optical receptacle changes, it is possible to suppress misalignment of the first optical surface and suppress a decrease in optical coupling efficiency. In addition, the photoelectric conversion element package and the optical receptacle body can be fixed by deformation suppression member 230.

[0047] [Embodiment 3] 3A is a diagram showing optical module 300 according to embodiment 3. Optical module 300 according to embodiment 3 differs from optical module 200 according to embodiment 2 in that optical receptacle body 320 has protection portion 326 for first optical surface 121 that is arranged around first optical surface 121.

[0048] In the optical module 300 according to the third embodiment, the same members as those in the optical module 200 according to the second embodiment are denoted by the same reference numerals and the description thereof will be omitted.

[0049] As described above, in the optical module according to the third embodiment, optical receptacle body 320 has protective portion 326. This protects first optical surface 121 and prevents it from being damaged. Protective portion 326 is disposed so as to surround first optical surface 121. Protective portion 326 may be cylindrical or may be a convex portion. When protective portion 326 is a convex portion, there are two or more convex portions. The end portion of protective portion 326 on the photoelectric conversion element package 110 side is configured to be located closer to photoelectric conversion element package 110 than the top of first optical surface 121.

[0050] (effect) According to the optical receptacle according to the third embodiment, even if the temperature around the optical receptacle changes, it is possible to suppress displacement of the first optical surface and suppress a decrease in the optical coupling efficiency. In addition, first optical surface 121 can be protected by protective portion 326.

[0051] [Embodiment 4] 3B is a diagram showing optical module 400 pertaining to embodiment 4. In optical module 400, optical receptacle body 420 has groove portion 127 arranged around first optical surface 121. In optical module 400, members similar to those in optical module 100 are given the same reference numerals and descriptions thereof will be omitted.

[0052] Nothing may be disposed in groove portion 127, or deformation suppressing material 128 may be disposed therein. In the present embodiment, deformation suppressing material 128 is disposed in groove portion 127 as shown in FIG. 3B.

[0053] The depth of groove 127 is preferably greater than the width of groove 127. By making groove 127 relatively deep, first optical surface 121 becomes independent of the expansion and contraction of the surrounding material, and the position of first optical surface 121 is further prevented from shifting due to temperature changes. In this embodiment, the bottom of groove 127 is located closer to optical transmission body 150 than second optical surface 122.

[0054] Deformation suppressing material 128 is a material having a smaller linear expansion coefficient than optical receptacle body 420. Examples of deformation suppressing material 128 include an adhesive (cured product). Because deformation suppressing material 128 is a material having a smaller linear expansion coefficient than optical receptacle body 420, it suppresses expansion and contraction of the optical receptacle, and further suppresses displacement of the position of first optical surface 121.

[0055] (effect) According to the optical receptacle according to the fourth embodiment, even if the temperature around the optical receptacle changes, it is possible to suppress misalignment of the first optical surface and suppress a decrease in optical coupling efficiency. [Industrial Applicability]

[0056] The optical receptacle and optical module according to the present invention are useful for optical communications using an optical transmission medium. [Explanation of symbols]

[0057] 10. Adhesive 100, 200, 300, 400 Optics Modules 110 Photoelectric conversion element package 111 Cabinet 112 Photoelectric conversion element 113 Leads 114 Light emitting element 115 Photodetector 120, 220, 320, 420 Optical receptacle body 121 1st optical surface 122 Second optical surface 126 Cylindrical part 127 Groove 128 Deformation-suppressing materials 129 Ferrule receiving section 130, 230 Deformation suppression member 140, 240, 340, 440 Optical Receptacle 150 Optical transmission body 151 Ferrule 326 Protection Department CA1 1st center axis CA2 2nd center axis

Claims

1. An optical receptacle for optically coupling a photoelectric conversion element and an optical transmission body when disposed between the photoelectric conversion element package including the photoelectric conversion element and the optical transmission body, comprising: An optical receptacle body; a deformation suppression member configured to surround the optical receptacle body and made of a material having a linear expansion coefficient smaller than that of the optical receptacle body; having The optical receptacle body includes: a first optical surface for allowing light emitted from the photoelectric conversion element package to enter an interior of the optical receptacle body or for allowing light that has traveled through the interior of the optical receptacle body to exit toward the photoelectric conversion element package; a second optical surface for emitting light that has traveled inside the optical receptacle body toward the optical transmission body or for causing light emitted from the optical transmission body to enter the optical receptacle body; and having at least a portion of an optical path between the first optical surface and the second optical surface is surrounded by the deformation suppression member, the deformation suppression member is joined to the optical receptacle body, one end of the deformation suppression member is configured to surround the optical receptacle body and the other end is configured to accommodate at least a portion of the photoelectric conversion element package such that the first optical surface and the photoelectric conversion element face each other; The deformation suppressing member includes a first deformation suppressing member and a second deformation suppressing member, the first deformation suppression member is configured to surround the optical receptacle body, the second deformation suppressing member is configured to accommodate at least a portion of the photoelectric conversion element package such that the first optical surface faces the photoelectric conversion element; Optical receptacle.

2. The optical receptacle according to claim 1 , wherein an end of the deformation suppression member facing the optical transmission body is located closer to the second optical surface than an edge of the first optical surface.

3. The optical receptacle according to claim 1 , wherein the optical receptacle body and the deformation suppression member are joined by adhesive.

4. The optical receptacle according to any one of claims 1 to 3, wherein the optical receptacle body further has a cylindrical portion arranged to surround the first optical surface, for accommodating at least a portion of the photoelectric conversion element package so that the first optical surface faces the photoelectric conversion element.

5. a photoelectric conversion element package including a photoelectric conversion element; The optical receptacle according to any one of claims 1 to 4 for optically coupling the photoelectric conversion element and the optical transmission body; An optical module comprising:

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