JP6506138B2 - Optical module and receptacle for optical module - Google Patents

Description

  The present invention relates to an optical module and a receptacle for the optical module.

  When optically connecting a photoelectric conversion element mounted on a circuit board and an optical fiber, alignment by active alignment (active alignment) may be performed. In the active alignment, for example, the photoelectric conversion element and the optical fiber are moved relative to each other so that light is most strongly incident on the optical fiber in a state where the photoelectric conversion element emits light, and alignment of both is performed. . Such active alignment takes a long process time, resulting in low productivity and high cost.

  There is a method of performing passive alignment for active alignment. For example, Patent Document 1 describes a method of passively aligning the optical axis of the optical fiber on the optical connector side by fitting the positioning hole of the optical connector to the positioning pin of the connector holder on the circuit board. There is.

Patent No. 4970608

  In Patent Document 1, an optical connector holds an end of a multi-core optical fiber tape, and two positioning holes (positioning portions) of the optical connector are arranged to sandwich optical axes of a plurality of optical signals. There is. In such an arrangement, since the optical axes of the plurality of optical signals and the two positioning portions are arranged in a line, the optical connector and the connector holder become wide. When the layout on the circuit board is restricted, the optical connector and the connector holder may not be made wide, and the optical axes of the plurality of optical signals and the two positioning portions may not be arranged in a line.

  As described later, in the case where the positioning unit is disposed offset with respect to the alignment direction of the optical axes of the plurality of optical signals, the distance between the positioning unit and the optical axis of the optical signal changes according to the temperature change. There will be new problems. As a result, when the environmental temperature changes, the optical axis on the circuit board side and the optical axis on the optical connector side may be shifted, and the optical loss may increase.

  An object of the present invention is to suppress an optical loss due to a temperature change while arranging a positioning portion in a staggered manner with respect to the alignment direction of the optical axes of a plurality of optical signals.

  The main invention for achieving the above object is to fit a receptacle having a substrate on which a plurality of optical signal input / output ends are lined up, a receptacle side positioning part, fixed to the substrate, and the receptacle side positioning part An optical connector having a connector-side positioning portion and holding an end of a plurality of optical fibers, and a surface of the optical connector on the side of the receptacle has a plurality of optical signal input / output portions in a first direction The connector-side positioning portion is arranged in a line in the second direction crossing the first direction with respect to the input / output portion, and the receptacle is a body portion fixed to a substrate, and the body portion And a projecting portion which protrudes in the second direction, the receptacle side positioning portion is disposed on the projecting portion, and the position of the receptacle side positioning portion in the second direction is It is an optical module, characterized in that positioned on the end side of the projecting portion than said input and output ends.

  Other features of the present invention will become apparent from the description of the specification and the drawings described below.

  According to the optical module according to the present invention, it is possible to suppress the light loss due to the temperature change while disposing the positioning portion in a shifted manner in the alignment direction of the optical axes of the plurality of optical signals.

FIG. 1A is a perspective view of the optical connector 20 of the first embodiment. FIG. 1B is a perspective view of the optical connector 20 of the comparative example. FIG. 2 is a cross-sectional view of the optical module 100 according to the first embodiment. FIG. 3 is a cross-sectional view of the optical module 100 according to the second embodiment. FIG. 4 is a perspective view of the optical connector 20 'of the third embodiment.

  At least the following matters will be clear from the description of the specification and drawings to be described later.

  It has a substrate on which the input and output ends of a plurality of optical signals are lined up, a receptacle side positioning part, a receptacle fixed to the substrate, and a connector side positioning part to be fitted with the receptacle side positioning part And an optical connector for holding an end of the fiber, wherein a plurality of optical signal input / output units are arranged in a first direction on the surface of the optical connector on the receptacle side, and the connector side positioning unit is inserted The receptacle is disposed offset in a second direction intersecting the first direction with respect to the output part, and the receptacle includes a main body fixed to a substrate, and a projection projecting from the main body in the second direction And the receptacle side positioning portion is disposed on the projecting portion, and the position of the receptacle side positioning portion in the second direction is an end side of the projecting portion with respect to the input / output end. It becomes clear that the light module, characterized in that position. According to such an optical module, it is possible to suppress an optical loss due to a temperature change while disposing the positioning portion in a staggered manner in the arrangement direction of the optical axes of the plurality of optical signals.

The linear expansion coefficient of the receptacle is a value smaller than the linear expansion coefficient of the optical connector,
The spacing in the second direction from the end of the fixing portion of the main body portion fixed to the substrate to the receptacle-side positioning portion is greater than the spacing in the second direction from the input / output portion to the connector-side positioning portion Long is desirable. Thereby, the light loss due to the temperature change can be suppressed.

  It is preferable that a contact portion capable of coming into contact with the substrate when the optical connector is attached is formed in the protrusion. As a result, even if the protrusion is subjected to a force when the optical connector is attached, deformation of the protrusion can be suppressed.

The linear expansion coefficient of the receptacle is a value larger than the linear expansion coefficient of the optical connector,
The spacing in the second direction from the end of the fixing portion where the main body portion is fixed to the substrate to the receptacle side positioning portion is greater than the spacing in the second direction from the input / output portion to the connector side positioning portion Short is desirable. Thereby, the light loss due to the temperature change can be suppressed.

  It is desirable that the main body portion has a housing portion for housing a photoelectric conversion element to be the input / output terminal. Thus, the input / output end of the optical signal can be positioned closer to the main body than the fixed end of the receptacle.

  A receptacle for an optical module, wherein an input / output end of a plurality of optical signals is fixed to a substrate aligned in a first direction, and the optical connector is positioned with respect to the substrate. A receptacle-side positioning portion that includes a projecting portion that protrudes in a second intersecting direction and that is fitted to the connector-side positioning portion of the optical connector is disposed in the projecting portion, and the second of the receptacle-side positioning portions The optical module receptacle is characterized in that the directional position is located closer to the end of the protrusion than the input / output end. According to such an optical module receptacle, light loss due to temperature change can be suppressed.

=== First Embodiment ===
FIG. 1A is a perspective view of the optical connector 20 of the first embodiment. FIG. 2 is a cross-sectional view of the optical module 100 according to the first embodiment.

  In the following description, each direction is defined as follows. The input / output direction (optical path direction) of the optical signal between the optical connector 20 and the receptacle 10 is "vertical direction", the side of the optical connector 20 with respect to the receptacle 10 is "upper", and the opposite side is "lower". Do. Further, the direction in which the plurality of optical fibers 5A (see FIG. 1A) constituting the optical fiber tape 5 are arranged is referred to as "left-right direction". Further, a direction perpendicular to the vertical direction and the lateral direction is referred to as "longitudinal direction", the side from which the optical fiber 5A extends from the optical connector 20 is referred to as "rear", and the opposite side is referred to as "front". In addition, the thing of the left-right direction may be called "1st direction", and the thing of the front-back direction may be called "2nd direction." In the second direction (front-rear direction), the side of the end of the projecting portion 13 protruding from the main body 12 of the receptacle 10 may be referred to as the “tip side” and the opposite side may be referred to as the “body side”. .

  The optical module 100 has a circuit board 1, a receptacle 10, and an optical connector 20, as shown in FIG. The optical module 100 is a device that performs at least one of transmission and reception of an optical signal. The optical module 100 may be an optical transmitter module (transmitter) that transmits an optical signal, or an optical receiver module (receiver) that receives an optical signal, or an optical that performs both transmission and reception of an optical signal. It may be a transceiver module (transmitter / receiver).

  The circuit board 1 is a board provided with input and output ends of a plurality of optical signals. Here, the photoelectric conversion element 3 is mounted on the upper surface of the circuit board 1, and the light emitting unit or the light receiving unit on the upper surface of the photoelectric conversion element 3 is an input / output terminal of an optical signal. However, a light guide may be formed on the circuit board 1 and an end of the light guide may be an input / output end of an optical signal. The optical axis of the optical signal at the input / output end is a direction (vertical direction) perpendicular to the circuit board 1. Further, the direction in which the plurality of input / output terminals are arranged is the left-right direction (the direction perpendicular to the sheet of FIG. 2: the first direction). Other elements (not shown in FIG. 2) such as drive elements for driving the photoelectric conversion elements 3 are also mounted on the upper surface of the circuit board 1. The receptacle 10 is fixed in advance to the upper surface of the circuit board 1 to form a circuit board with a receptacle. The circuit board 1 is, for example, a glass substrate, and the linear expansion coefficient α0 of the circuit board 1 is sufficiently smaller than that of the resin receptacle 10 and the optical connector 20 (for example, about 1/10).

  The receptacle 10 is a member that aligns the optical connector 20 with the circuit board 1 (here, mainly the photoelectric conversion element 3 of the circuit board 1). The receptacle 10 has a positioning hole 11 (a receptacle side positioning portion), and is fixed to the top surface of the circuit board 1. By fitting the positioning pins 21 of the optical connector 20 into the positioning holes 11 of the receptacle 10, the optical connector 20 is aligned with the circuit board 1. The upper surface of the receptacle 10 is a mounting surface on which the optical connector 20 is mounted, and faces the lower surface of the optical connector 20. The receptacle 10 may constitute a connector holder by providing a holder for fixing and holding the optical connector 20 on the upper surface of the receptacle 10.

  The receptacle 10 has two positioning holes 11, and the two positioning holes 11 are arranged side by side in the left-right direction (the direction perpendicular to the paper surface of FIG. 2). The positioning hole 11 is a hole parallel to the up and down direction (incoming and outgoing direction of the light signal). Here, the positioning hole 11 is a through hole, but may be a non-through hole.

  The receptacle 10 is formed of a transparent resin capable of transmitting an optical signal, and the optical signal input / output between the photoelectric conversion element 3 and the optical connector 20 passes through the receptacle 10. However, a through hole 14 (see FIG. 3 of the second embodiment described later) may be formed in the receptacle 10, and an optical signal may be passed through the through hole 14. In this case, the receptacle 10 is formed of an opaque material. It is possible. The receptacle 10 of the present embodiment is made of, for example, glass-containing polycarbonate, and the linear expansion coefficient α1 of the receptacle 10 is, for example, 1.5 to 3.0 × 10 ^ (-5).

  In the present embodiment, the receptacle 10 has a main body 12 and a protrusion 13. The main body portion 12 is a portion fixed to the circuit board 1. The main body portion 12 is fixed (here, adhesively fixed) to the upper surface of the circuit board 1 in the fixing portion 121. The protruding portion 13 is a portion protruding from the main body 12 along the upper surface of the substrate. Here, the protrusion 13 protrudes from the main body 12 to the rear side (second direction). The protrusion 13 is formed in a cantilever shape without being fixed to the circuit board 1, and an end on the front side (main body side) is supported by the main body 12. Although the contact part 13A which protruded to the circuit board 1 side is formed in the lower surface of the projection part 13, this contact part 13A is not fixed to the circuit board 1. As shown in FIG. The protrusion 13 will be described later.

  The optical connector 20 is a member for holding an end of the optical fiber 5A for transmitting an optical signal. The optical connector 20 of this embodiment is made of, for example, polyetherimide, and the linear expansion coefficient α2 of the optical connector 20 is, for example, 5.0 × 10 ^ (-5).

  The optical connector 20 has a positioning pin 21 (connector-side positioning portion). The optical connector 20 has two positioning pins 21, and the two positioning pins 21 are arranged side by side in the left-right direction (see FIG. 1A). The positioning pin 21 protrudes from the lower surface of the optical connector 20. The positioning pin 21 is a pin that is parallel to the up-down direction (in and out direction of the light signal).

  As shown in FIG. 2, the optical connector 20 has a plurality of optical fiber holes 22, an optical fiber insertion port 23, an optical signal surface 24, and a reflection surface 25.

The optical fiber hole 22 is a hole for inserting the end of the optical fiber 5A. The bare fiber which removed the coating | cover from the optical fiber core wire is inserted in the optical fiber hole 22, and the edge part of optical fiber 5A is being fixed to the optical connector 20 by the adhesive agent. A plurality of optical fiber holes 22 are formed side by side in the left-right direction (the direction perpendicular to the paper surface of FIG. 2).
The optical fiber insertion port 23 is an insertion port into which a plurality of optical fibers 5A (optical fiber tapes 5) are inserted.

  The light signal surface 24 is a surface on which a plurality of light signals are incident or emitted, and is formed on the lower surface of the optical connector 20 (see also FIG. 1A). When the optical connector 20 is attached to the receptacle 10, the optical signal surface 24 corresponds to the photoelectric conversion element 3 (input and output end of the circuit board 1) with the receptacle 10 interposed therebetween. A plurality of lenses 24A are formed on the light signal surface 24, and each lens 24A is disposed on the optical axis of each light signal. As shown in FIG. 1A, the lenses 24A, which are input / output units for a plurality of light signals, are arranged side by side in the left-right direction. In addition, the optical axis of the lens 24A, which is an input / output unit of an optical signal, is the optical axis of the optical signal entering / exiting at the optical signal surface 24. In addition, the input / output part of an optical signal may be formed in planar shape instead of lens shape.

  The reflective surface 25 is a surface that reflects an optical signal. A recess is formed on the upper surface of the optical connector 20, and a reflecting surface 25 is formed by the inclined surface of the recess. The reflecting surface 25 may be a plane, or a lens surface may be formed on the optical axis of each light signal. When an optical signal is emitted from the end face of the optical fiber 5A, the optical signal is reflected by the reflection surface 25 and emitted downward from the optical signal surface 24 (to the side of the receptacle 10). When an optical signal is incident from the optical signal surface 24, the optical signal is reflected by the reflection surface 25 and is incident on the end face of the optical fiber 5A. The optical connector 20 functions as an optical path conversion unit by having the reflection surface 25.

FIG. 1B is a perspective view of the optical connector 20 of the comparative example. On the lower surface of the optical connector 20 of the comparative example, a plurality of lenses 24A are arranged in the left-right direction, and two positioning pins 21 are disposed so as to sandwich the plurality of lenses 24A. When the positioning pin 21 and the plurality of lenses 24A are arranged in a line as in the comparative example, the distance between the two positioning pins 21 becomes wide, and the optical connector 20 becomes wide (the dimension in the horizontal direction becomes long ). Moreover, in the comparative example, it is necessary to widen the space in the left-right direction of the two positioning holes 11 (receptacle side positioning portions) of the receptacle 10, and the receptacle 10 also becomes wide. However, when the layout on the circuit board 1 is restricted, it may not be permitted to fix the wide receptacle 10 to the circuit board 1.
On the other hand, in the present embodiment, as shown in FIG. 1A, the plurality of lenses 24A (input / output units for light signals) are arranged in the left-right direction (first direction), and the positioning pins 21 (connector-side positioning units) The lens 24 </ b> A (an input / output unit for an optical signal) is disposed so as to be offset in the front-rear direction (second direction). Thus, in the present embodiment, the distance between the two positioning pins 21 can be narrowed as compared with the comparative example, and the width of the optical connector 20 can be narrowed. Further, in the present embodiment, it is possible to narrow the distance between the two positioning holes 11 (receptacle side positioning portions) of the receptacle 10 in the left-right direction.

  In the present embodiment, the distance between the two positioning pins 21 in the left-right direction (first direction) is shorter than the length of the plurality of lenses 24A aligned in the left-right direction. More specifically, the inner dimensions of the two positioning pins 21 (the distance between the insides of the pins where the distance between the two positioning pins 21 is the narrowest) is shorter than the length of the plurality of lenses 24A aligned in the left-right direction (first direction) . However, in order to make the distance between the two positioning pins 21 narrower than the length in the left-right direction of the plurality of lenses 24A (plurality of input / output units) as described above, the positioning pins 21 are shifted in the front-rear direction with respect to the lenses 24A. Need to be placed.

In the case where the positioning pin 21 is arranged to be displaced in the front-rear direction with respect to the lens 24A, a new problem arises that the distance between the positioning pin 21 and the lens 24A changes in the front-rear direction when a temperature change occurs. . That is, as shown in FIG. 2, when the linear expansion coefficient of the optical connector 20 is α2 and the distance between the positioning pin 21 and the lens 24A in the front-rear direction is L2, if the temperature change ΔT occurs, the positioning pin 21 and the lens The amount of change Δ2 of the distance L2 in the front-rear direction with 24A is as follows.
Δ2 = α2 × L2 × ΔT

  If the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side deviate by the amount of change Δ2, the optical loss will increase. Therefore, in the present embodiment, the positioning hole 11 is disposed in the protruding portion 13 of the receptacle 10, and the position of the positioning hole 11 is closer to the tip end (the protruding portion 13) than the photoelectric conversion element 3 (input / output end of optical signal) By arranging on the side, the influence of the change amount Δ2 of the optical connector 20 is alleviated by utilizing the fact that the length of the protrusion 13 also changes when the temperature changes. Hereinafter, this point will be described.

First, in order to simplify the description, the case where the linear expansion coefficient α0 of the circuit board 1 is sufficiently small to be negligible will be described (α0 = 0).
As shown in FIG. 2, in the first embodiment, the linear expansion coefficient α1 of the receptacle 10 is a value smaller than the linear expansion coefficient α2 of the optical connector 20 (α1> α2). Assuming that the distance between the fixed end 121A of the receptacle 10 (the end on the tip side of the fixed portion 121 of the main body 12) and the positioning hole 11 is L1, photoelectric conversion element 3 (input and output) The amount of change Δ1 of the distance between the end) and the positioning hole 11 in the front-rear direction is as follows (however, the linear expansion coefficient α0 of the circuit board 1 is zero).
Δ1 = α1 × L1 × ΔT

Then, if Δ1 = Δ2 is satisfied, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be offset, and the deviation between the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side can be eliminated. Become. In order to satisfy Δ1 = Δ2, the interval L1 is as follows.
L1 = (α2 / α1) × L2

  In the first embodiment, since the linear expansion coefficient α1 of the receptacle 10 is a value smaller than the linear expansion coefficient α2 of the optical connector 20 (α1 <α2), α2 / α1 becomes a value larger than one. For this reason, as shown in FIG. 2, the distance L1 in the front-rear direction from the fixed end 121A of the receptacle 10 to the positioning hole 11 is longer than the distance L2 in the front-rear direction from the lens 24A to the positioning pin 21.

Even if Δ1 = Δ2 is not completely established, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change may be suppressed. That is, when the absolute value of the difference between the change amount Δ2 and the change amount Δ1 is smaller than the change amount Δ2, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be suppressed. In other words, if 0 <Δ1 <2 × Δ2 holds, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be suppressed. In order to satisfy 0 <Δ1 <2 × Δ2, the interval L1 is as follows.
0 <L1 <2 × (α2 / α1) × L2

  That is, the distance L1 is desirably greater than zero and desirably less than twice of (α2 / α1) × L2. When the interval L1 satisfies the condition of the above equation, the influence of the change amount Δ2 on the side of the optical connector 20 at the time of temperature change can be suppressed, and the deviation between the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side can be suppressed. .

Next, the case of considering the linear expansion coefficient α0 of the circuit board 1 is also considered. When considering the linear expansion coefficient α0 of the circuit board 1, when the temperature change ΔT occurs, the photoelectric conversion element 3 (input of an optical signal) from the fixed end 121A of the receptacle 10 (the end on the tip end of the fixed portion 121 of the main body 12). The change amount Δ0 of the distance L0 to the output end) corresponds to α0 × L0 × ΔT. Therefore, the change amount Δ1 of the distance between the photoelectric conversion element 3 (input and output end) and the positioning hole 11 in the front-rear direction when the temperature change ΔT occurs is as follows.
Δ1 = α1 × L1 × ΔT − α0 × L0 × ΔT

Therefore, in order to satisfy the condition of Δ1 = Δ2 which is a condition for canceling out the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change, the interval L1 is as shown in the following equation.
L1 = (α2 / α1) × L2 + (α0 / α1) × L0

Since L1 = L2 + L0, as shown in FIG. 2, the interval L1 can be rewritten as in the following equation.
L1 = {(α2-α0) / (α1-α0)} × L2

  In addition, in order to suppress the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change, 0 <Δ1 <2 × Δ2 may be established as described above.

  According to the above-described first embodiment, the positioning hole 11 (receptacle side positioning portion) of the receptacle 10 is disposed in the projecting portion 13 protruding from the fixing portion 121 and the front-rear direction (second direction) of the positioning hole 11 The position of is located on the tip side (end side of the protrusion 13) than the photoelectric conversion element 3 (input / output end). Since the positioning hole 11 of the receptacle 10 is positioned on the tip side of the photoelectric conversion element 3, the positioning pin 21 of the optical connector 20 at the time of fitting is positioned on the tip side of the lens 24A (input / output unit) become. As a result, even if the distance L2 between the lens 24A of the optical connector 20 and the positioning pin 21 changes at the time of temperature change, the length of the protrusion 13 also changes temperature to utilize the optical axis and light of the circuit board 1 side. Misalignment with the optical axis on the connector 20 side can be suppressed.

  Further, as in the first embodiment, when the linear expansion coefficient α1 of the receptacle 10 is smaller than the linear expansion coefficient α2 of the optical connector 20 (α1 <α2), the fixed end 121A of the receptacle 10 (main portion 12 It is desirable that the distance L1 in the front-rear direction from the end on the tip side of the fixed portion 121: the root of the protrusion 13 to the positioning hole 11 be longer than the distance L2 in the front-rear direction from the lens 24A to the positioning pin 21. Thereby, even when the temperature changes, it is possible to suppress the deviation between the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side.

  Further, in the first embodiment, as shown in FIG. 2, the contact portion 13 </ b> A protruding toward the circuit board 1 is formed on the lower surface on the tip end side of the protrusion 13. Thus, even if the cantilevered protrusion 13 receives a force when the optical connector 20 is attached, the contact 13A contacts the upper surface of the circuit board 1, thereby suppressing the deformation of the protrusion 13. In particular, when the gap L1 is longer than the gap L2 as in the first embodiment, it is advantageous to form the contact portion 13A on the lower surface of the protrusion 13. The contact portion 13A may be formed at the tip of the projection 13, may be formed in the vicinity of the positioning hole 11, or may be formed between the positioning hole 11 and the photoelectric conversion element 3.

=== Second Embodiment ===
FIG. 3 is a cross-sectional view of the optical module 100 according to the second embodiment. In the second embodiment, the linear expansion coefficient α1 of the receptacle 10 is a value larger than the linear expansion coefficient α2 of the optical connector 20 (in contrast, in the first embodiment, α1 <α2).

  Also in the second embodiment, the direction in which the input and output ends of the plurality of optical signals of the circuit board 1 are aligned in the left and right direction (first direction), and the plurality of lenses 24A (input and output portions of optical signals) are in the left and right direction (The direction perpendicular to the sheet of FIG. 3: the first direction). The positioning pin 21 (connector-side positioning unit) is disposed to be offset in the front-rear direction (second direction) with respect to the lens 24A (input / output unit for light signal). Thereby, also in the second embodiment, the widths of the optical connector 20 and the receptacle 10 can be narrowed as in the first embodiment.

  Also in the second embodiment, when a temperature change occurs, there arises a problem that the distance between the positioning pin 21 and the lens 24A in the front-rear direction changes. Assuming that the linear expansion coefficient of the optical connector 20 is α2 and the distance between the positioning pin 21 and the lens 24A in the front-rear direction is L2, as shown in FIG. 2, when the temperature change ΔT occurs, the positioning pin 21 and the lens 24A As in the first embodiment, the change amount Δ2 of the distance L2 in the front-rear direction of the distance is Δ2 = α2 × L2 × ΔT.

  Therefore, also in the second embodiment, the positioning hole 11 is disposed in the projecting portion 13 of the receptacle 10, and the position of the positioning hole 11 is closer to the tip end (the projecting portion 13) than the photoelectric conversion element 3 (input / output end of optical signal). By arranging at the end portion side, the influence of the change amount Δ2 of the optical connector 20 is alleviated by utilizing the fact that the length of the protrusion 13 also changes when the temperature changes.

  Also in the second embodiment, when the space L1 in the front-rear direction from the fixed end 121A of the receptacle 10 (the end on the tip end side of the fixed portion 121 of the main body 12) to the positioning hole 11 is photoelectrically generated As in the first embodiment, the change amount Δ1 of the distance between the conversion element 3 (input / output end) and the positioning hole 11 in the front-rear direction is Δ1 = α1 × L1 × ΔT (provided that α0 = 0. ). Then, if Δ1 = Δ2 is satisfied, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be offset, and the deviation between the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side can be eliminated. Become. In order to satisfy Δ1 = Δ2, the interval L1 is L1 = (α2 / α1) × L2, as in the first embodiment.

  In the second embodiment, since the linear expansion coefficient α1 of the receptacle 10 is larger than the linear expansion coefficient α2 of the optical connector 20 (α1> α2), α2 / α1 is smaller than 1. Therefore, as shown in FIG. 3, the distance L1 in the front-rear direction from the fixed end 121A of the receptacle 10 to the positioning hole 11 is shorter than the distance L2 in the front-rear direction from the lens 24A to the positioning pin 21.

  Thus, in the second embodiment, since the distance L1 is shorter than the distance L2, the photoelectric conversion element 3 (input / output end of optical signal) is closer to the main body side (front side in the figure) than the fixed end 121A of the receptacle 10. It will be located. For this reason, as shown in FIG. 3, it is desirable to form the accommodating part 122 in the main-body part 12 of the receptacle 10, and to accommodate the photoelectric conversion element 3 in the accommodating part 122. As shown in FIG. Then, it is desirable that the main body 12 be fixed to the circuit board 1 in the front and rear fixing portions 121 of the housing portion 122.

  Even if Δ1 = Δ2 is not completely established, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change may be suppressed. That is, when the absolute value of the difference between the change amount Δ2 and the change amount Δ1 is smaller than the change amount Δ2, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be suppressed. In other words, if 0 <Δ1 <2 × Δ2 holds, the influence of the change amount Δ2 on the optical connector 20 side at the time of temperature change can be suppressed. In order to satisfy 0 <Δ1 <2 × Δ2, the interval L1 may be within the range of 0 <L1 <2 × (α2 / α1) × L2, as in the first embodiment. That is, the distance L1 is desirably greater than zero and desirably less than twice of (α2 / α1) × L2.

  According to the second embodiment described above, the positioning hole 11 (receptacle side positioning portion) of the receptacle 10 is disposed in the projecting portion 13 protruding from the fixing portion 121 and the front-rear direction (second direction) of the positioning hole 11 The position of is located on the tip side (end side of the protrusion 13) than the photoelectric conversion element 3 (input / output end). Since the positioning hole 11 of the receptacle 10 is positioned on the tip side of the photoelectric conversion element 3, the positioning pin 21 of the optical connector 20 at the time of fitting is positioned on the tip side of the lens 24A (input / output unit) become. As a result, even if the distance L2 between the lens 24A of the optical connector 20 and the positioning pin 21 changes at the time of temperature change, the length of the protrusion 13 also changes temperature to utilize the optical axis and light of the circuit board 1 side. Misalignment with the optical axis on the connector 20 side can be suppressed.

  When the linear expansion coefficient α1 of the receptacle 10 is larger than the linear expansion coefficient α2 of the optical connector 20 as in the second embodiment (α1> α2), the fixed end 121A of the receptacle 10 (main portion 12) It is desirable that the distance L1 in the front-rear direction from the end on the tip side of the fixing portion 121 to the positioning hole 11 be shorter than the distance L2 in the front-rear direction from the lens 24A to the positioning pin 21. Thereby, even when the temperature changes, it is possible to suppress the deviation between the optical axis on the circuit board 1 side and the optical axis on the optical connector 20 side.

  The receptacle 10 of the second embodiment has a through hole 14 for passing an optical signal. Thereby, the receptacle 10 of the second embodiment can be formed of an opaque material.

=== Third Embodiment ===
FIG. 4 is a perspective view of the optical connector 20 'of the third embodiment. In the optical connector 20 'of the third embodiment, the optical fiber 5A extends from the upper end side (in contrast to the above embodiment, the optical fiber 5A extends from the rear side of the optical connector 20). Further, the optical connector 20 'of the third embodiment has a positioning hole 21' as a connector-side positioning portion (in contrast, in the above embodiment, the connector-side positioning portion is the positioning pin 21). The optical connector 20 'of the third embodiment does not have the above-described reflection surface 25 and does not have a function as an optical path conversion unit.

Also in the third embodiment, the direction in which the input and output ends of the plurality of optical signals of the circuit board 1 are aligned in the left and right direction (first direction), and the plurality of lenses 24A (input and output units for optical signals) (The direction perpendicular to the sheet of FIG. 4: the first direction). The positioning hole 21 ′ (connector-side positioning portion) is disposed to be offset in the front-rear direction (second direction) with respect to the lens 24A (input / output portion for light signal). Therefore, also in the third embodiment, there is a problem that the distance between the positioning hole 21 ′ and the lens 24A in the front-rear direction changes when a temperature change occurs.
Therefore, also in the third embodiment, it is desirable to attach the optical connector 20 'to the receptacle 10 of the first embodiment or the second embodiment.

=== Other Embodiments ===
The embodiments described above are to facilitate the understanding of the present invention, and are not to be interpreted as limiting the present invention. It goes without saying that the present invention can be modified and improved without departing from the gist thereof, and that the present invention includes equivalents thereof.

1 circuit board, 3 photoelectric conversion element (input and output end),
5 optical fiber tape, 5A optical fiber,
10 receptacles, 11 positioning holes,
12 main unit,
121 fixed part, 121 A fixed end, 122 accommodating part,
13 protrusions, 13A contacts, 14 through holes,
20 optical connectors, 21 positioning pins,
22 fiber optic holes, 23 fiber optic inserts,
24 light signal surface, 24A lens (input and output section),
25 reflective surfaces, 100 light modules

Claims (6)

A substrate on which a plurality of optical signal input / output terminals are arranged;
A receptacle having a receptacle side positioning part, and fixed to the substrate;
An optical connector having a connector-side positioning portion fitted with the receptacle-side positioning portion, and holding an end of a plurality of optical fibers;
In the surface on the receptacle side of the optical connector, a plurality of optical signal input / output units are arranged in a first direction, and the connector side positioning unit intersects the first direction with respect to the input / output unit. They are arranged in two directions,
The receptacle has a main body portion fixed to a substrate, and a protruding portion protruding from the main body portion in the second direction.
The receptacle side positioning portion is disposed on the projecting portion,
The position of the said receptacle direction positioning part of the said 2nd direction is located in the edge part side of the said protrusion part rather than the said input-output end, The optical module characterized by the above-mentioned. The optical module according to claim 1, wherein
The linear expansion coefficient of the receptacle is a value smaller than the linear expansion coefficient of the optical connector,
The spacing in the second direction from the end of the fixing portion of the main body portion fixed to the substrate to the receptacle-side positioning portion is greater than the spacing in the second direction from the input / output portion to the connector-side positioning portion A light module characterized by long. The optical module according to claim 2, wherein
An optical module characterized in that a contact portion capable of coming into contact with the substrate when the optical connector is mounted is formed in the projecting portion. The optical module according to claim 1, wherein
The linear expansion coefficient of the receptacle is a value larger than the linear expansion coefficient of the optical connector,
The spacing in the second direction from the end of the fixing portion where the main body portion is fixed to the substrate to the receptacle side positioning portion is greater than the spacing in the second direction from the input / output portion to the connector side positioning portion A light module characterized by its shortness. The optical module according to claim 4, wherein
The said main-body part has an accommodating part which accommodates the photoelectric conversion element used as the said input-output end, The optical module characterized by the above-mentioned. An optical module receptacle for fixing an optical connector with respect to a substrate, wherein an input / output end of a plurality of optical signals is fixed to the substrate arranged in the first direction,
A body portion fixed to the substrate;
And a protruding portion protruding in a second direction intersecting the first direction,
A receptacle-side positioning portion to be fitted to the connector-side positioning portion of the optical connector is disposed on the projecting portion,
The receptacle for an optical module, wherein the position in the second direction of the receptacle-side positioning portion is positioned closer to the end of the projecting portion than the input / output end.

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