JP2014211555A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module capable of suppressing damage to a positioning hole and a positioning pin.SOLUTION: An optical module includes: a transparent substrate 20 into which light can penetrate; a photoelectric conversion element 31 that is mounted on the transparent substrate 20 and emits light toward the transparent substrate 20 or receives light that penetrated the transparent substrate 20; and a supporting member 40 that supports optical fiber 50 and forms an optical path between the photoelectric conversion element and optical fiber 50 with the transparent substrate 20. In the supporting member 40, a positioning pin 43 having a tapered surface is formed. In the transparent substrate 20, a non-penetrating positioning hole 23 is formed having the tapered surface of the same angle as the tapered surface of the positioning pin 43. Under a state where the tapered surface of the positioning pin 43 comes into contact with the tapered surface of the positioning hole 23, the positioning pin 43 of the supporting member 40 is inserted into the positioning hole 23 of the transparent substrate 20.

Description

  The present invention relates to an optical module.

  In the field of high-speed optical communication using an optical fiber, an optical transceiver is used as a component that mutually converts an electrical signal and an optical signal. The specifications (shape, dimensions, pin assignment, etc.) of pluggable optical transceivers are standardized by MSA (Multi Source Agreement) agreed by an industry group that handles optical transceivers. According to these pluggable optical transceivers, a cage is installed on a main board on the communication device side (host side), and an optical module incorporating a photoelectric conversion element and a circuit board is detachably inserted into the cage. When the optical module is inserted into the cage, the circuit board in the optical module is electrically and mechanically connected to the electrical interface connector in the cage. Thereby, the optical signal transmitted and received by the optical fiber and the electric signal processed by the main board on the communication device side can be converted into each other by the photoelectric conversion element and the circuit board in the optical module.

  Patent Document 1 describes an optical module in which a positioning pin (symbol 9) is inserted into a substrate (symbol 1) on which a positioning hole (symbol 11) is formed to align an optical axis.

JP 2005-17684 A

  In Patent Document 1, the positioning hole has a constant diameter, and the positioning pin also has a constant diameter. When the positioning hole and the positioning pin have such a cylindrical shape, a clearance is required between the positioning hole and the positioning pin due to the fit tolerance, and a positioning error is generated by this clearance.

  On the other hand, when the positioning pin has a conical shape like the conical protrusions (reference numerals 4A and 4B) of Patent Document 1, the positioning pin can be brought into contact with the positioning hole without a gap, but the taper surface of the positioning pin is positioned. Point contact is made with the corner of the hole, and stress is concentrated at the point contact portion. Patent Document 1 also describes that the conical protrusions (reference numerals 4A and 4B) are plastically deformed by the corners in the vicinity of the openings of the recesses (reference numerals 5A and 5B) (see paragraphs 0021 and 0027 of Patent Document 1). ). As described above, when the contact area between the positioning hole and the positioning pin is reduced, the mechanical strength of the positioning hole and the positioning pin is lowered, and the positioning hole and the positioning pin may be damaged.

  An object of the present invention is to suppress damage to positioning holes and positioning pins.

  The main invention for achieving the above object is a transparent substrate capable of transmitting light, and photoelectric conversion mounted on the transparent substrate and emitting light toward the transparent substrate or receiving light transmitted through the transparent substrate. And a support member that supports the optical fiber and forms an optical path between the photoelectric conversion element and the optical fiber together with the transparent substrate, and a positioning pin having a tapered surface is formed on the support member. The transparent substrate is formed with a non-penetrating positioning hole having a taper surface having the same angle as the taper surface of the positioning pin, and the taper surface of the positioning pin and the taper surface of the positioning hole. In the optical module, the positioning pin of the support member is inserted into the positioning hole of the transparent substrate.

  Other characteristics of the present invention will be made clear by the description and drawings described later.

  According to the present invention, damage to the positioning hole and the positioning pin can be suppressed.

FIG. 1 is an explanatory diagram of a pluggable optical transceiver. FIG. 2A is a perspective view of the circuit board 10 and the like in the housing 1A of the optical module 1 as viewed obliquely from above. FIG. 2B is a perspective view of the circuit board 10 and the like as viewed obliquely from below. FIG. 3 is a schematic configuration diagram of the optical module 1 inserted into the cage 2. 4A to 4C are schematic explanatory views showing that the positioning pins 43 of the optical path converter 40 are inserted into the positioning holes 23 of the glass substrate 20 and the glass substrate 20 and the optical path converter 40 are positioned. 5A and 5B are sectional views of the positioning hole 23 and the positioning pin 43 of the reference example. 6A and 6B are sectional views of the positioning hole 23 and the positioning pin 43 of the first embodiment. FIG. 7A is an enlarged view of the vicinity of the root of the positioning pin 43 of the first embodiment. FIG. 7B is an enlarged view of the vicinity of the root of the positioning pin 43 of the reference example. 8A and 8B are sectional views of the positioning hole 23 and the positioning pin 43 of the second embodiment. 9A and 9B are sectional views of the positioning hole 23 and the positioning pin 43 of the third embodiment. 10A and 10B are sectional views of the positioning hole 23 and the positioning pin 43 of the fourth embodiment.

  At least the following matters will be apparent from the description and drawings described below.

A transparent substrate capable of transmitting light, a photoelectric conversion element mounted on the transparent substrate, emitting light toward the transparent substrate or receiving light transmitted through the transparent substrate, and supporting an optical fiber; A support member that forms an optical path between the conversion element and the optical fiber together with the transparent substrate; and a positioning pin having a tapered surface is formed on the support member, and the positioning signal is formed on the transparent substrate. A non-penetrating positioning hole having a tapered surface having the same angle as the tapered surface of the pin is formed, and the tapered surface of the positioning pin is in contact with the tapered surface of the positioning hole. The optical module is characterized in that the positioning pin of the support member is inserted into the positioning hole.
According to such an optical module, damage to the positioning hole and the positioning pin can be suppressed.

  It is desirable that the support member has a recess around the base of the positioning pin. As a result, even when the corner portion of the positioning pin is rounded when the positioning pin is manufactured, high-precision positioning is possible without being affected by the roundness of the corner portion.

As for the side wall surface inside the said recessed part, it is desirable to become the extension surface of the said taper surface of the said positioning pin. Thereby, since the taper surface is formed to the inner side than the surface of the support member, highly accurate positioning is possible without being affected by the roundness of the root of the positioning pin.

  It is desirable that the tapered surface of the positioning hole is formed at an opening of the positioning hole. Alternatively, it is desirable that chamfering is performed on the opening side of the positioning hole with respect to the tapered surface.

  The positioning pins are preferably formed in a truncated cone shape. Thereby, all the side surfaces of the positioning pins become tapered surfaces, and the contact area between the positioning holes and the positioning pins can be increased.

=== First Embodiment ===
<Overall configuration>
FIG. 1 is an explanatory diagram of a pluggable optical transceiver. An optical transceiver having both an optical transmitter and an optical receiver is sometimes referred to as an optical transceiver, but here, an optical transceiver having only one is also referred to as an optical transceiver. The pluggable optical transceiver in the figure is of the QSFP type (QSFP: Quad Small Form Factor Pluggable) defined by MSA (Multi Source Agreement). The pluggable optical transceiver has an optical module 1 and a cage 2.

  In the drawing, two types of optical modules 1 are depicted. As shown in the drawing, an optical fiber (including a cord) may be fixed to the optical module 1 or may be detachable. One of the two cages 2 in the figure is drawn with the heat sink 3 removed and partially broken so that the inside can be seen.

  In the following description, as shown in FIG. 1, front and rear, up and down, and left and right are defined. That is, the insertion port side of the cage 2 into which the optical module 1 is inserted is referred to as “front”, and the opposite side is referred to as “rear”. In the optical module 1, the side from which the optical fiber (including the cord) extends is referred to as “front”, and the opposite side is referred to as “rear”. Further, when viewed from the main board on which the cage 2 is provided, the side of the surface on which the cage 2 is provided is “upper”, and the opposite side is “lower”. Also, the direction orthogonal to the front-rear direction and the up-down direction is referred to as “left-right”.

  A cage 2 is installed on the main board on the communication device side (host side). The cage 2 is provided on a main board of a blade server in the data center, for example.

  The optical module 1 is detachably inserted into the cage 2. The optical module 1 includes a photoelectric conversion element 31 and a circuit board 10 in a housing 1A, and mutually converts an optical signal transmitted / received by an optical fiber and an electric signal processed by a main board on a communication device side. To do.

  The cage 2 accommodates the optical module 1 in a detachable manner. The cage 2 is a box-shaped member having a rectangular section in the front-rear direction with an insertion slot for inserting the optical module 1 on the front side. The cage 2 is formed by bending a metal plate so as to open the front side. An accommodating portion for accommodating the optical module 1 is formed in the cage 2 by bending the metal plate into a rectangular cross section. A connector 2 </ b> A is provided on the rear side inside the cage 2. When the optical module 1 is inserted into the cage 2, the circuit board in the optical module 1 is electrically and mechanically connected to the connector 2 </ b> A in the cage 2. Thereby, an electrical signal is transmitted between the optical module 1 and the main board.

  The upper surface of the cage 2 has an opening, and a heat sink 3 is attached so as to close the opening. The heat sink 3 includes a large number of heat radiation fins (heat radiation pins) for radiating the heat of the optical module 1 inserted into the cage 2 to the outside.

<Internal configuration of optical module 1>
FIG. 2A is a perspective view of the circuit board 10 and the like in the housing 1A of the optical module 1 as viewed obliquely from above. FIG. 2B is a perspective view of the circuit board 10 and the like as viewed obliquely from below. FIG. 3 is a schematic configuration diagram of the optical module 1 inserted into the cage 2. 4A to 4C are schematic explanatory views showing that the positioning pins 43 of the optical path converter 40 are inserted into the positioning holes 23 of the glass substrate 20 and the glass substrate 20 and the optical path converter 40 are positioned.

  As shown in the figure, the optical module 1 includes a circuit board 10, a glass substrate 20, and an optical path changer 40 in a housing 1A.

  The circuit board 10 is a plate-like printed board that constitutes an electronic circuit. A connection portion 11 (card edge connector) for connecting to a connector 2A (connector socket) in the cage 2 is formed at the rear end portion of the circuit board 10. The connection portion 11 is formed on both upper and lower surfaces of the circuit board 10 and a large number of terminals are formed side by side in the left-right direction.

  An accommodation window 12 for accommodating the optical path converter 40 is formed in the circuit board 10. A circuit board side electrode 13 is formed on the upper surface of the circuit board 10 so as to surround the housing window 12. A glass substrate 20 is mounted on the upper surface of the circuit board 10 so as to close the accommodation window 12. In other words, the housing window 12 of the circuit board 10 is positioned below the glass substrate 20, and the housing window 12 of the circuit board 10 is closed by the lower surface of the glass substrate 20. A glass substrate side electrode 22 is formed on the lower surface of the glass substrate 20, and the glass substrate 20 is connected to the circuit substrate side electrode 13 and the glass substrate side electrode 22 while closing the housing window 12 of the circuit substrate 10. It is mounted on the circuit board 10.

  The housing window 12 is a through hole (opening) formed in the circuit board 10. The upper portion of the optical path changer 40 is inserted into the accommodation window 12. The lower part of the optical path changer 40 protrudes downward from the receiving window 12, and the optical fiber 50 extends forward from the protruding part. However, when the optical path changer 40 is thinner than the circuit board 10, the lower part of the optical path changer 40 does not protrude downward from the receiving window 12. In this case, if the reflecting portion 42 is configured to reflect light at an obtuse angle, the optical fiber 50 can be easily pulled out from the optical path converter 40.

  The glass substrate 20 is a transparent glass substrate that can transmit light. The glass substrate 20 is comprised from glass materials, such as quartz glass and borosilicate glass, for example, and the borosilicate glass is employ | adopted here. A plurality of through vias 21 are formed in the glass substrate 20 along the shape of the receiving window 12 of the circuit board 10.

  A glass substrate side electrode 22 is formed on the lower surface of the glass substrate 20 (the surface opposite to the mounting surface on which the light emitting unit 31 is mounted). The glass substrate side electrode 22 is formed outside the through via 21. Further, the glass substrate side electrode 22 is formed along the outside of the accommodation window 12 of the circuit board 10. The glass substrate side electrode 22 is electrically connected to the circuit substrate side electrode 13 on the upper surface of the circuit substrate 10. The through via 21 is used for wiring between the glass substrate side electrode 22, the light emitting unit 31, and the driving element 32.

  Two positioning holes 23 for positioning the optical path changer 40 are formed on the lower surface of the glass substrate 20. The positioning hole 23 does not penetrate the glass substrate 20 and is formed to be a non-through hole. By making the positioning hole 23 a non-through hole, it becomes possible to mount a component (for example, the drive element 32) on the upper side of the positioning hole 23 and to arrange a wiring to the component. The degree of freedom of component mounting and wiring on the upper surface is increased.

  If the positioning hole 23 is a through hole, an opening having a small diameter is formed on the upper surface of the glass substrate 20 when the tapered surface 23A is formed in the positioning hole 23 as described later, and the diameter is small. Stress tends to concentrate on the opening, and the mechanical strength of the glass substrate 20 decreases. On the other hand, if the positioning hole 23 is a non-through hole, an opening (a small diameter opening) is not formed on the upper surface of the glass substrate 20 even if the tapered surface 23A is formed in the positioning hole 23. The mechanical strength of can be maintained.

  A light emitting unit 31 is mounted on the upper surface of the glass substrate 20. A driving element 32 for driving the light emitting unit 31 is also mounted on the upper surface of the glass substrate 20 (the mounting surface of the light emitting unit 31). The light emitting unit 31 and the driving element 32 are disposed inside the through via 21. In other words, the light emitting unit 31 and the driving element 32 are mounted on the upper surface of the glass substrate 20 so as to be positioned above the receiving window 12 of the circuit board 10.

  The light emitting unit 31 is a photoelectric conversion element that converts an optical signal and an electrical signal. Here, a VCSEL (Vertical Cavity Surface Emitting Laser) that emits light perpendicular to the substrate is employed as the light emitting unit 31. Note that a light receiving unit that converts an optical signal into an electrical signal may be mounted on the glass substrate 20 as a photoelectric conversion element. Further, both the light emitting unit and the light receiving unit may be mounted on the glass substrate 20.

  The light emitting unit side electrode 31A and the light emitting surface 31B of the light emitting unit 31 are formed on the lower surface (the surface on the glass substrate 20 side). The light emitting unit 31 is flip-chip mounted on the glass substrate 20 and irradiates light toward the glass substrate 20. Since the light emitting unit side electrode 31A and the light emitting surface 31B of the light emitting unit 31 are located on the same side (the lower surface on the side of the glass substrate 20), if the light emitting unit 31 is flip-chip mounted on the glass substrate 20, the light emitting surface 31B. Faces the glass substrate 20, and the light emitting surface 31B is not exposed to the outside.

  3 shows one light emitting surface 31B of the light emitting unit 31, the light emitting unit 31 includes a plurality of (for example, four) light emitting surfaces 31B arranged in a direction perpendicular to the paper surface.

  The optical path converter 40 is an optical component that converts the optical path of the light emitted from the light emitting unit 31. The optical path converter 40 also functions as a support member that supports one end of the optical fiber 50 and forms the optical path between the light emitting unit 31 and the optical fiber 50 together with the transparent substrate. The optical path changer 40 is a member that is positioned and attached to the glass substrate 20. The optical path changer 40 is inserted into the receiving window 12 from the lower side of the circuit board 10.

  The optical path changer 40 includes a lens unit 41 and a reflection unit 42. The lens unit 41 is formed on the upper surface of the optical path changer 40. The reflection part 42 is formed on the lower surface of the optical path changer 40.

  The lens portion 41 is a portion formed in a convex lens shape so that light can be focused. However, the lens portion 41 is formed in a concave portion recessed from the upper surface so as not to protrude from the upper surface of the optical path changer 40. Since the lens portion 41 is formed to be recessed from the upper surface of the optical path changer 40, the lens portion 41 is prevented from coming into contact with the lower surface of the glass substrate 20. The lens unit 41 focuses the light emitted from the light emitting unit 31, guides the light to the reflecting unit 42, and causes the light to enter the optical fiber 50. When the light receiving unit is mounted on the glass substrate 20, the lens unit 41 focuses the light reflected from the reflecting unit 42 on the light receiving unit. The lens unit 41 faces the light emitting surface 31B of the light emitting unit 31 with the glass substrate 20 interposed therebetween.

  The reflection part 42 is a part for reflecting light. The optical axis of the light emitted from the light emitting unit 31 is the vertical direction (the direction perpendicular to the substrate such as the circuit board 10 or the glass substrate 20), but the optical axis of the light reflected by the reflecting unit 42 is the front-rear direction (circuit (Direction parallel to the substrate such as the substrate 10 or the glass substrate 20). The light reflected by the reflection unit 42 enters the optical fiber 50 attached to the optical path changer 40. When the light receiving part is mounted on the glass substrate 20, the reflecting part 42 reflects the light emitted from the optical fiber 50, guides it to the lens part 41, and focuses it on the light receiving part.

  In addition, the reflection part 42 in a figure is drawn so that the optical axis of reflected light may become the front-back direction (direction parallel to substrates, such as the circuit board 10 and the glass substrate 20). However, the reflection part 42 is not restricted to what reflects light at 90 degree | times. The reflection unit 42 may be configured to reflect light at an obtuse angle (for example, about 100 degrees). The light whose optical axis is in the vertical direction (direction perpendicular to the substrate such as the circuit board 10 or the glass substrate 20) has a component in the front-rear direction (direction parallel to the substrate such as the circuit board 10 or the glass substrate 20). It only has to be reflected. For example, when the root of the optical fiber 50 is relatively above the optical path converter 40 or when the thickness of the optical path converter 40 is thinner than the thickness of the circuit board 10, the optical fiber 50 is pulled out from the optical path converter 40. In order to facilitate, it is preferable that the reflecting portion 42 be configured to reflect light at an obtuse angle.

  The optical fiber 50 is aligned and attached so as to have a predetermined positional relationship with respect to the lens portion 41 and the reflecting portion 42 of the optical path changer 40.

  In the optical path changer 40 in the figure, a lens portion 41 is provided only at a site where light enters. However, a lens part may be provided also in a part where light is emitted (part facing the end of the optical fiber 50), and the optical path converter 40 may be provided with two lens parts. If the two lens portions are collimator lenses, parallel light can be propagated in the optical path changer 40.

  On the upper surface of the optical path changer 40, two positioning pins 43 for insertion into the positioning holes 23 of the glass substrate 20 are formed so as to protrude. The positioning pin 43 of the optical path converter 40 is fitted into the positioning hole 23 of the glass substrate 20, whereby the optical axis of the lens unit 41 of the optical path converter 40 and the optical axis of the light emitting unit 31 mounted on the glass substrate 20. Alignment is performed.

  The optical path converter 40 is integrally formed of resin. That is, the lens part 41, the reflection part 42, and the positioning pin 43 of the optical path changer 40 are integrally formed of resin. Moreover, the optical path changer 40 is shape | molded by resin which can permeate | transmit light, and here polyetherimide resin is used.

  The optical path changer 40 is a thicker part than the other parts in order to secure the area of the reflection part 42 and to secure the area for connecting the end of the optical fiber 50. However, when the circuit board 10, the glass substrate 20, and the optical path changer 40 are simply stacked by arranging the upper part of the thick optical path changer 40 in the housing window 12 (or via a relay board). Compared with the case where the glass substrate 20 and the optical path changer 40 are attached to the circuit board 10), the height of the optical module is reduced.

<About the shapes of the positioning hole 23 and the positioning pin 43>
5A and 5B are sectional views of the positioning hole 23 and the positioning pin 43 of the reference example. This sectional view shows a cross section of a plane including the central axis of the positioning hole 23 and the positioning pin 43. In the figure, θ 2 is an angle formed by the inner surface of the positioning hole 23 that contacts the positioning pin 43 and the lower surface of the glass substrate 20. Further, the angle θ4 in the figure is an angle formed between the generatrix of the tapered surface 43A of the frustoconical positioning pin 43 and the upper surface of the optical path changer 40.

  In the reference example, the angle θ2 is larger than the angle θ4 (θ2> θ4). As a result, when the positioning pin 43 is inserted into the positioning hole 23, the positioning hole 23 and the positioning pin 43 come into point contact as shown in the region surrounded by the dotted line in FIG. 5B, and stress is concentrated on this point contact portion. Resulting in. Thus, when the contact area between the positioning hole 23 and the positioning pin 43 is reduced, the mechanical strength of the positioning hole 23 and the positioning pin 43 is reduced, and the positioning hole 23 and the positioning pin 43 are likely to be damaged.

  6A and 6B are sectional views of the positioning hole 23 and the positioning pin 43 of the first embodiment. This sectional view also shows a cross section of a plane including the central axes of the positioning holes 23 and the positioning pins 43. Similar to the above-described reference example, the optical path changer 40 is formed with a frustoconical positioning pin 43 having a tapered surface 43A. In the figure, θ4 is an angle formed by the bus of the tapered surface 43A of the positioning pin 43 and the upper surface of the optical path converter 40.

  In the first embodiment, a tapered surface 23 </ b> A is formed on the inner surface of the positioning hole 23. In the first embodiment, the tapered surface 23 </ b> A of the positioning hole 23 is formed at the opening of the positioning hole 23. The tapered surface 23A is an inner surface of a conical shape (conical truncated cone shape). In the figure, θ 2 is an angle formed by the generatrix of the tapered surface 23 A of the positioning hole 23 and the lower surface of the glass substrate 20.

  In the first embodiment, the angle θ2 is the same as the angle θ4 (θ2 = θ4). That is, the positioning hole 23 having the tapered surface 23A having the same angle as the tapered surface 43A of the positioning pin 43 is formed on the lower surface of the glass substrate 20. As a result, when the positioning pin 43 is inserted into the positioning hole 23, the tapered surface 23A of the positioning hole 23 and the tapered surface 43A of the positioning pin 43 come into surface contact as shown in FIG. 6B. For this reason, compared with the reference example, the contact area of the positioning hole 23 and the positioning pin 43 becomes large. Thereby, the stress is dispersed, and damage to the positioning holes 23 and the positioning pins 43 can be suppressed.

The positioning hole 23 is formed by subjecting the glass substrate 20 to sandblasting. According to the sandblasting, it is possible to form the positioning hole 23 in a non-penetrating manner or to form the tapered surface 23 </ b> A in the positioning hole 23. However, after forming the positioning hole 23 by sandblasting, the tapered surface 23A may be formed using a micro drill. In addition, after forming the positioning hole 23 and the tapered surface 23 </ b> A using a processing tool, the inner surface of the positioning hole 23 may be subjected to a surface treatment such as etching.
Compared with processing (sand blasting) of the tapered surface 23A of the positioning hole 23, processing (resin molding) of the tapered surface 43A of the positioning pin 43 is easier. For this reason, it is desirable to design the taper surface 43A of the positioning pin 43 so as to match the angle of the taper surface 23A of the positioning hole 23. For example, when the angle θ2 of the taper surface 23A of the positioning hole 23 by sandblasting is 70 degrees, the angle of the taper surface 43A of the positioning pin 43 that can be molded into an arbitrary shape with resin may be designed to 70 degrees.

  The state in which the angle of the taper surface 23A of the positioning hole 23 and the angle of the taper surface 43A of the positioning pin 43 is the same indicates not only the state in which the angles coincide in all the regions of the taper surface 23A and the taper surface 43A. This includes a state in which the angles coincide with each other in a part of the tapered surface 23A and the tapered surface 43A. This is because if the angle is the same in a partial region of the tapered surface 23A and the tapered surface 43A, the contact area at the contact portion between the tapered surface 23A and the tapered surface 43A is larger than that of the reference example.

  When the angle θ2 of the taper surface 23A and the angle θ4 of the taper surface 43A have a tolerance, the range of the angle θ2 and the range of the angle θ4 overlap with the state where the angles of the taper surface 23A and the taper surface 43A are the same. Includes state. In particular, the tolerance of the angle θ2 of the taper surface 23A by sandblasting is larger than the tolerance of the angle θ4 of the taper surface 43A by resin molding. In such a case, the range of the angle θ2 includes the range of the angle θ4. Good. Thereby, a contact area becomes larger than a reference example in the contact part of taper surface 23A and taper surface 43A.

  Further, when the tapered surface 23A is a rough surface and the generatrix of the taper surface 23A (intersection line between an arbitrary plane including the central axis and the taper surface) is not a straight line, the pair including the generatrix and having the smallest interval. The angle between the parallel straight line and the lower surface of the glass substrate 20 is defined as θ2. Similarly, when the generatrix of the taper surface 43A is not a straight line, an angle formed by a pair of parallel straight lines including the generatrix and having a minimum interval and the upper surface of the optical path changer 40 is defined as θ4. Even in such a case, if the angle θ2 and the angle θ4 are the same, the contact area at the contact portion between the tapered surface 23A and the tapered surface 43A is larger than that of the reference example.

  FIG. 7A is an enlarged view of the vicinity of the root of the positioning pin 43 of the first embodiment. FIG. 7B is an enlarged view of the vicinity of the root of the positioning pin 43 of the reference example.

  Generally, since the resin shrinks when the resin is molded, the surface shape of the resin molded product does not directly reflect the shape of the inner surface of the mold. For example, the corner of the molded product may be rounded. As already described, the optical path changer 40 of the first embodiment is formed integrally with a transparent resin, and the positioning pins 43 are also formed integrally with other parts of the optical path changer 40. And like the reference example shown to FIG. 7B, the corner | angular part (part shown by the arrow in a figure) of the base of the positioning pin 43 may be rounded. Since this roundness is not formed uniformly around the positioning pin 43 (because the roundness at the base of the positioning pin 43 cannot be controlled), when this portion comes into contact with the positioning hole 23, the positioning hole 23 or the positioning pin 43 The optical axis on the glass substrate 20 side (the optical axis of the light emitted from the light emitting unit 31 and the optical axis on the optical path converter 40 side (the light of the lens unit 41) This may cause a positional deviation from the axis.

  Therefore, as shown in FIG. 7A, in the first embodiment, an annular recess 43 </ b> B is formed on the upper surface of the optical path changer 40 so as to surround the base of the positioning pin 43. Furthermore, the inner side wall surface of the recess 43 </ b> B is an extended surface of the tapered surface 43 </ b> A of the truncated conical positioning pin 43. That is, the taper surface 43 </ b> A of the positioning pin 43 is formed to the inner side (the side opposite to the side where the positioning pin 43 protrudes) from the upper surface of the optical path changer 40. Thereby, even if the corner of the base of the positioning pin 43 is rounded, the portion is positioned below the upper surface of the optical path converter 40. In this way, the rounded corners of the positioning pins 43 are prevented from coming into contact with the positioning holes 23.

=== Second Embodiment ===
In the first embodiment described above, the tapered surface 23A of the positioning hole 23 is formed in the opening of the positioning hole 23 (see FIG. 6A). However, the tapered surface 23A of the positioning hole 23 is not limited to being formed in the opening.

  8A and 8B are sectional views of the positioning hole 23 and the positioning pin 43 of the second embodiment.

  In the second embodiment, chamfering is performed on the opening side of the tapered surface 23A. For this reason, the tapered surface 23 </ b> A of the positioning hole 23 of the second embodiment is formed above the opening of the positioning hole 23. According to the second embodiment, since the chamfering process is performed on the opening of the positioning hole 23, the operation of inserting the positioning pin 43 into the positioning hole 23 is facilitated.

  Also in the second embodiment, the angle θ2 is the same as the angle θ4 (θ2 = θ4). As a result, when the positioning pin 43 is inserted into the positioning hole 23, the tapered surface 23A of the positioning hole 23 and the tapered surface 43A of the positioning pin 43 come into surface contact as shown in FIG. 8B. For this reason, compared with the reference example of FIG. 6B, the contact area of the positioning hole 23 and the positioning pin 43 becomes large. Thereby, the stress is dispersed, and damage to the positioning holes 23 and the positioning pins 43 can be suppressed.

  Also in the second embodiment, like the positioning pin 43 of the first embodiment shown in FIG. 7A, an annular recess 43 </ b> B may be formed so as to surround the base of the positioning pin 43. In this case, the side wall surface inside the recess 43B is preferably an extension surface of the tapered surface 43A of the truncated conical positioning pin 43.

=== Third Embodiment ===
In the first embodiment described above, the positioning pin 43 is formed in a truncated cone shape (see FIG. 6A). That is, in the first embodiment, the side surfaces of the positioning pins 43 are all tapered surfaces 43A. However, the shape of the positioning pin 43 is not limited to the truncated cone shape, and all the side surfaces of the positioning pin 43 may not be the tapered surface 43A.

  9A and 9B are sectional views of the positioning hole 23 and the positioning pin 43 of the third embodiment. In the third embodiment, a taper surface 43A is formed at the base of the positioning pin 43, and the upper side of the taper surface 43A (the tip side of the positioning pin 43) is a curved surface.

  Also in the third embodiment, the angle θ2 is the same as the angle θ4 (θ2 = θ4). As a result, when the positioning pin 43 is inserted into the positioning hole 23, the tapered surface 23A of the positioning hole 23 and the tapered surface 43A of the positioning pin 43 are in surface contact as shown in FIG. 9B. For this reason, compared with the reference example of FIG. 6B, the contact area of the positioning hole 23 and the positioning pin 43 becomes large. Thereby, the stress is dispersed, and damage to the positioning holes 23 and the positioning pins 43 can be suppressed.

  Instead of forming the taper surface 43A at the base of the positioning pin 43, the taper surface 43A may be formed at the tip end side of the positioning pin 43, and the base side of the taper surface 43A may be a curved surface. Further, a curved surface may be formed on both the base side and the tip side of the tapered surface 43A of the positioning pin 43.

=== Fourth Embodiment ===
In the first embodiment described above, the positioning hole 23 is formed as a non-through hole whose back is narrowed by sandblasting. However, the positioning hole 23 is not limited to the shape with a deep back.

  10A and 10B are sectional views of the positioning hole 23 and the positioning pin 43 of the fourth embodiment.

  The positioning hole 23 of the fourth embodiment has a tapered surface 23 </ b> A formed by chamfering the opening after the diameter is formed in a cylindrical shape with a constant diameter. Even in such a shape, if the angle θ2 of the tapered surface 23A of the positioning hole 23 is the same as the angle θ4, the tapered surface 23A of the positioning hole 23 and the tapered surface 43A of the positioning pin 43 are in surface contact. For this reason, compared with the reference example of FIG. 6B, the contact area of the positioning hole 23 and the positioning pin 43 becomes large. Thereby, the stress is dispersed, and damage to the positioning holes 23 and the positioning pins 43 can be suppressed.

=== Others ===
The above-described embodiments are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be modified and improved without departing from the gist thereof, and it goes without saying that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<Positioning hole and positioning pin>
The positioning hole 23 described above is a deep non-through hole formed by sandblasting, but may be a positioning hole formed by another processing method or a positioning hole of another shape. However, the positioning hole 23 is preferably a non-through hole. By making the positioning hole 23 a non-through hole, the degree of freedom of component mounting and wiring on the upper surface of the glass substrate 20 is increased. If the positioning hole 23 is a non-through hole, an opening (opening having a small diameter) is not formed on the upper surface of the glass substrate 20 even if the tapered surface 23A is formed in the positioning hole 23. Strength can be maintained.

<About optical path converter>
In the above-described embodiment, the optical path changer (optical component) is made of resin. However, the optical component having the positioning pin may not be made of resin.

<About optical modules>
In the above embodiment, the QSFP type optical module has been described. However, the present invention is not limited to this type. It is also possible to apply to other types of optical modules (for example, CXP type and SFP type).

1 optical module, 1A housing,
2 cage, 2A connector, 3 heat sink,
10 circuit boards, 11 connections,
12 receiving window, 13 circuit board side electrode,
20 glass substrate (transparent substrate), 21 through via,
22 glass substrate side electrode, 23 positioning hole, 23A taper surface,
31 light emitting part, 31A light emitting part side electrode, 31B light emitting surface, 32 drive element,
40 optical path changer (supporting member), 41 lens part, 42 reflecting part,
43 positioning pin, 43A taper surface, 43B recess,
50 optical fiber

Claims (6)

A transparent substrate capable of transmitting light;
A photoelectric conversion element mounted on the transparent substrate and emitting light toward the transparent substrate or receiving light transmitted through the transparent substrate;
A support member that supports an optical fiber and forms an optical path between the photoelectric conversion element and the optical fiber together with the transparent substrate;
A positioning pin having a tapered surface is formed on the support member,
In the transparent substrate, a non-penetrating positioning hole having a tapered surface having the same angle as the tapered surface of the positioning pin is formed,
The optical module, wherein the positioning pin of the support member is inserted into the positioning hole of the transparent substrate in a state where the tapered surface of the positioning pin is in contact with the tapered surface of the positioning hole. The optical module according to claim 1,
An optical module, wherein the support member is formed with a recess around the base of the positioning pin. The optical module according to claim 2,
The optical module according to claim 1, wherein the inner side wall surface of the recess is an extension surface of the tapered surface of the positioning pin. The optical module according to any one of claims 1 to 3,
The optical module, wherein the tapered surface of the positioning hole is formed in an opening of the positioning hole. The optical module according to any one of claims 1 to 3,
A chamfering process is performed on the opening side of the positioning hole with respect to the tapered surface. An optical module according to any one of claims 1 to 5,
The optical module, wherein the positioning pin is formed in a truncated cone shape.

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