JP2005326884A - Optical module and optical connector equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module which is capable of suppressing deterioration of the efficiency of optical coupling, even with a temperature change and permits efficient optical communication, and to provide an optical connector equipped with the optical module. <P>SOLUTION: The optical module 1 is made by integrally molding an aspheric lens 11 and a holder 2 with plastic and is set so as to engage a photoelectric conversion element package 3 to a cylindrical part 8 of a holder 2. A flange part 15 which abuts against an opening end surface 16 of the cylindrical part 8 is formed on the photoelectric conversion element package 3. Then, the flange part 15 and the opening end surface 16 of the cylindrical part 8 are adhered and fixed, such that a gap is formed between the outer peripheral surface 18 of a cap 12 of the photoelectric conversion element package 3 and the inner peripheral surface of the cylindrical part 8. Further, the optical module 1 is constituted, such that a temperature change amount Δd2 of the distance d2, from the apex P1 of the aspheric lens 11 to the focus P2, is approximately equal to a temperature change amount ΔL of the length L of the axial direction from the apex P1 of the aspheric lens 11 to the opening end surface 16 of the cylindrical part 8. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical module for optical fiber communication and an optical connector including the same.

  An optical module for optical fiber communication includes a photoelectric conversion element package (for example, a package containing a semiconductor light emitting element such as a semiconductor laser or a semiconductor light receiving element such as a photodiode), a ferrule, a lens, and a holder that accommodates these. It is equipped with.

  Such an optical module is configured such that a photoelectric conversion element (semiconductor light-emitting element or semiconductor light-receiving element) in a photoelectric conversion element package and an optical fiber of a ferrule are optically coupled via a lens. It is.

  For example, in the optical modules disclosed in Patent Document 1 and Patent Document 2, since the components of the photoelectric conversion element package, the spherical lens, and the optical fiber of the ferrule are separate from each other, alignment is performed when accommodated in the holder. The work is done so that the optical axes of the parts are aligned.

JP-A-10-300994 (see paragraph numbers 0016 to 0019, FIGS. 6 and 7). JP 2002-43675 A (see paragraph numbers 0021 to 0025, FIG. 4).

  However, in the prior art disclosed in Patent Document 1 and Patent Document 2, as described above, each component of the photoelectric conversion element package, the spherical lens, and the optical fiber of the ferrule is separate, and each of these components is held in a holder. When assembling, the aligning work must be performed so that the optical axes of the respective parts are aligned, and the aligning work is difficult, so that the work efficiency is poor.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical module capable of improving the efficiency of alignment work during assembly and facilitating assembly, and an optical connector including the same.

  According to the first aspect of the present invention, a ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the optical fiber mounting hole and the cylindrical portion, and the ferrule and the photoelectric conversion element package are optically connected via the lens. An optical module coupled to the lens, wherein the lens and the holder are integrally formed of plastic.

  According to the second aspect of the present invention, a ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the optical fiber mounting hole and the cylindrical portion, and the ferrule and the photoelectric conversion element package are optically connected via the lens. It is related with the optical module couple | bonded with. In the optical module, the lens and the holder are integrally formed of plastic, and the photoelectric conversion element package is formed with a flange portion that abuts against an opening end surface of the cylindrical portion, and the flange portion and the cylindrical shape are formed. An opening end surface of the portion is bonded and fixed, and a gap is provided between the outer peripheral surface of the light source conversion element package and the inner peripheral surface of the cylindrical portion. Further, this optical module has a temperature change amount (Δd2) of a distance (d2) from the apex of the lens to the focal point and a temperature in an axial direction length (L) from the apex of the lens to the opening end surface of the cylindrical portion. The amount of change (ΔL) is almost equal.

  According to a third aspect of the present invention, a ferrule is fitted into an optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the optical fiber mounting hole and the cylindrical portion, and the ferrule and the photoelectric conversion element package are optically connected via the lens. It is related with the optical module couple | bonded with. In this optical module, the lens and the holder are integrally formed of plastic, and the cylindrical portion and the photoelectric conversion element package are bonded and fixed at the opening end of the cylindrical portion, and the light source conversion element package A gap is provided between the outer peripheral surface and the inner peripheral surface of the cylindrical portion. The optical module also includes a temperature change amount (Δd2) of a distance (d2) from the apex of the lens to the focal point and a temperature change amount of an axial length (L) from the apex of the lens to the bonded and fixed portion. (ΔL) is substantially equal.

  According to a fourth aspect of the present invention, a ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the optical fiber mounting hole and the cylindrical portion, and the ferrule and the photoelectric conversion element package are optically connected via the lens. It is related with the optical module couple | bonded with. In this optical module, the lens and the holder are integrally formed of plastic, and the opening end of the cylindrical portion and the photoelectric conversion element package are detachably engaged with each other, and the outer periphery of the light source conversion element package A gap is provided between the surface and the inner peripheral surface of the cylindrical portion. Further, this optical module has a temperature change (Δd2) of a distance (d2) from the apex of the lens to the focal point and a temperature change of an axial length (L) from the apex of the lens to the uneven engagement portion. The feature is that the quantity (ΔL) is substantially equal.

  A fifth aspect of the present invention relates to an optical connector comprising the optical module according to any of the first to fourth aspects of the present invention, and a housing that accommodates and holds the optical module.

  As described above, according to the present invention, since the aspheric lens is integrally formed with the holder, it is not necessary to align the optical axis of the aspheric lens with the axis of the holder, and the optical module is assembled. Work becomes easier and productivity of the optical module is improved.

  Further, according to the present invention, the number of parts can be reduced, and the productivity is improved as described above, so that the product price of the optical module can be reduced.

  Further, the present invention can reduce the deviation between the focal position of the aspherical lens and the position of the surface of the photoelectric conversion element package even when the ambient environmental temperature changes, thereby improving the optical coupling efficiency. Therefore, efficient optical communication becomes possible.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
1 and 2 are diagrams for explaining an optical module 1 according to an embodiment of the present invention. Among these, FIG. 1 is a longitudinal sectional view of a holder 2 constituting the optical module 1. FIG. 2 is a longitudinal sectional view schematically showing a state in which the photoelectric conversion element package 3 is attached to the holder 2.

  As shown in these drawings, the holder 2 is formed by injection molding a light-transmitting plastic (for example, PEI, PC, PMMA, etc.). An optical fiber attachment hole 6 for removably engaging the ferrule 5 is formed on one end side in the direction along the axis 4 of the holder 2. The optical fiber attachment hole 6 is opened on one end side in the direction along the axis 4 of the holder 2, and the ferrule 5 is accommodated and held therein. On the other end side in the direction along the axis 4 of the holder 2, a cylindrical portion 8 that accommodates and holds a photoelectric conversion element package (a semiconductor light emitting element or a package that accommodates a semiconductor light receiving element as a photoelectric conversion element) 3 is formed. ing.

  In addition, the holder 2 has an aspheric lens 11 projecting toward the photoelectric conversion element package 3 accommodated in the cylindrical portion 8 on the partition wall 10 positioned between the cylindrical portion 8 and the optical fiber mounting hole 6. It is integrally formed. The aspherical lens 11 is formed so that its optical axis coincides with the axis 4 of the holder 2 and has a shape represented by the following equation (Equation 1) (see FIG. 6).

光電変換素子パッケージ３は、略円筒状のキャップ１２の内部に収容した図示しない半導体発光素子（例えば、半導体レーザ等）から光を発光するか、又は図示しない半導体受光素子（フォトダイオード等）で光を受光するようになっている。そして、この光電変換素子パッケージ３のリード１３が突出するキャップ端面１４側には、キャップ１２の外周に突出する略円環状の鍔部１５が一体形成されている。この光電変換素子パッケージ３の鍔部１５は、ホルダ２の筒状部８の開口端面１６に突き当てられるようにして、ホルダ２の筒状部８の開口端面１６に接着剤１７で接着固定されるようになっている。また、この光電変換素子パッケージ３のキャップ１２は、その略円筒状の外周面１８がホルダ２の筒状部８の穴２０内に隙間嵌合しており、その略円筒状の外周面１８とホルダ２の筒状部８の内周面９との間に隙間が生じるようになっている。尚、キャップ１２は、プラスチック製のホルダ２と異なり、プラスチックよりも熱変形量が小さな金属で形成されている。

The photoelectric conversion element package 3 emits light from a semiconductor light emitting element (not shown) (for example, a semiconductor laser) accommodated in a substantially cylindrical cap 12 or light is emitted from a semiconductor light receiving element (photodiode or the like) not shown. Light is received. Then, a substantially annular flange portion 15 protruding to the outer periphery of the cap 12 is integrally formed on the cap end surface 14 side from which the lead 13 of the photoelectric conversion element package 3 protrudes. The flange portion 15 of the photoelectric conversion element package 3 is bonded and fixed to the opening end surface 16 of the cylindrical portion 8 of the holder 2 with an adhesive 17 so as to abut against the opening end surface 16 of the cylindrical portion 8 of the holder 2. It has become so. Further, the cap 12 of the photoelectric conversion element package 3 has a substantially cylindrical outer peripheral surface 18 fitted in a gap 20 in the hole 20 of the cylindrical portion 8 of the holder 2. A gap is formed between the inner peripheral surface 9 of the cylindrical portion 8 of the holder 2. Note that, unlike the plastic holder 2, the cap 12 is formed of a metal having a smaller amount of thermal deformation than plastic.

  Here, in the present embodiment, even when the temperature of the optical module 1 changes, the positional deviation between the focal point P2 of the aspheric lens 11 and the surface (light emitting surface or light receiving surface) 21 of the photoelectric conversion element package 3 is small. Thus, the dimensions of the holder 2 are determined. Note that the surface 21 of the photoelectric conversion element package 3 shown in FIG. 2 schematically represents the light emitting surface of the semiconductor light emitting element accommodated therein or the light receiving surface of the semiconductor light receiving element for convenience of explanation. Therefore, in FIG. 2, the focal point P <b> 2 of the aspherical lens 11 coincides with the light emitting surface of the semiconductor light emitting element accommodated inside the photoelectric conversion element package 3 or the light receiving surface of the semiconductor light receiving element.

  That is, the dimension (d2) from the apex P1 of the aspherical lens 11 to the focal point P2 of the aspherical lens 11 increases / decreases according to the refractive index and the lens thickness that change in response to the temperature change, for example, the temperature is Δt. When it rises, it changes to (d2 + Δd2). The axial length (L) from the apex P1 of the aspherical lens 11 to the opening end surface 16 of the cylindrical portion 8 increases or decreases due to the expansion or contraction of the plastic that is the material of the holder 2, and the linear expansion coefficient of the plastic The amount of increase / decrease (ΔL) varies depending on the amount of change in temperature and the amount of change in temperature. For example, when the temperature rises by Δt, it changes to (L + ΔL). On the other hand, the cap 12 made of metal (for example, SUS) engaged with the holder 2 has a ratio (α1 / α2) between the linear expansion coefficient α1 and the linear expansion coefficient α2 of the holder 2 made of plastic (for example, PEI). Since it is about (α1 / α2 = 0.12 to 0.18), it is assumed that it is not temperature-deformed. As a result, when ΔL = Δd2, the position of the focal point P2 of the aspherical lens 11 and the surface 21 of the photoelectric conversion element package 3 can be approximately matched, and the focal point P2 of the aspherical lens 11 and the photoelectric conversion element The positional deviation from the surface 21 of the package 3 can be reduced.

  As described above, in the optical module 1, when ΔL = Δd2, the position of the focal point P2 of the aspherical lens 11 and the position of the surface 21 of the photoelectric conversion element package 3 are substantially matched, and the optical coupling efficiency is good. Become. Here, Δd2 is uniquely determined according to the temperature change Δt by appropriately determining the material, shape, and focal length (d2) of the aspheric lens 11. This is because the refractive index and the linear expansion coefficient are values inherent to the material of the aspherical lens 11.

  Therefore, the dimension (L) such that ΔL = Δd2, that is, the axial length (L) of the cylindrical portion 8 from the apex P1 of the aspherical lens 11 to the bonded portion is obtained as follows. it can.

尚、ホルダ２の光ファイバ取付穴６の底部には、フェルール５の光ファイバ７の先端がホルダ２に接触して傷付くのを防止するため、光ファイバ取付穴６よりも小径の逃がし穴２２が形成されている。

In addition, in order to prevent the tip of the optical fiber 7 of the ferrule 5 from coming into contact with the holder 2 and being damaged at the bottom of the optical fiber mounting hole 6 of the holder 2, an escape hole 22 having a smaller diameter than the optical fiber mounting hole 6. Is formed.

  According to the optical module 1 of the present embodiment configured as described above, since the aspherical lens 11 can be formed integrally with the holder 2, the optical axis of the aspherical lens 11 and the axis 4 of the holder 2 are Is not necessary, the assembly work of the optical module 1 is facilitated, and the productivity of the optical module 1 is improved.

  Further, according to the present embodiment, the number of parts can be reduced, and the productivity can be improved as described above, so that the product price of the optical module 1 can be reduced.

  In addition, according to the present embodiment, since the aspherical lens 11 is formed integrally with the holder 2, there is no possibility of dust entering between the aspherical lens 11 and the photoelectric conversion element package 3, and optical communication is performed. It can be done reliably. However, according to the conventional example in which a separate lens is bonded and fixed to the holder, there is a possibility that dust may enter between the lens and the photoelectric conversion element package through a gap in a portion where uneven adhesion occurs.

  Further, according to the optical module of the present embodiment, even if the ambient environmental temperature changes, the position of the focal point P2 of the aspherical lens 11 and the position of the surface 21 of the photoelectric conversion element package 3 substantially coincide with each other. Since efficient coupling efficiency is improved, efficient optical communication is enabled.

  Further, according to the present embodiment, the amount of deviation between the position of the focal point P2 of the aspherical lens 11 and the surface 21 of the photoelectric conversion element package 3 due to temperature change can be reduced, so that the lens magnification can be increased. it can. On the other hand, when the amount of deviation of the focal length of the lens due to temperature change is large, the optical coupling efficiency is lowered, so that the lens magnification cannot be increased.

  Further, according to the present embodiment, as described above, since the magnification of the aspherical lens 11 can be increased, light having a wider light emitting angle can be emitted from the optical fiber as compared with the case where a lens with a small magnification is used. 7 so that strong light can be transmitted.

  In addition, since the optical module 1 of the present embodiment can increase the magnification of the aspherical lens 11 as described above, a single mode optical fiber is used as compared with the case where a lens with a low magnification is used. In some cases, more efficient optical communication is possible.

  The optical module 1 shown in FIG. 2 is accommodated in the housing 23 as the light emitting optical module 1 or the light receiving optical module 1 as shown in FIG. The optical connector 24 is configured by being soldered to the electric board that is not to be used.

  Moreover, since the optical module 1 of this Embodiment can enlarge the magnification of the aspherical lens 11, it is especially effective when used as the optical module 1 for light emission.

(Second Embodiment)
FIG. 3 is a view for explaining the optical module 1 according to the second embodiment of the present invention, and is a longitudinal sectional view schematically showing a state in which the photoelectric conversion element package 3 is attached to the holder 2. In the present embodiment, components that are substantially the same as those of the optical module 1 of the first embodiment described above are denoted by the same reference numerals, and descriptions that are the same as those of the first embodiment are omitted. To do.

  In the optical module 1 of the present embodiment, the adhesive portion 25 formed at the opening end of the cylindrical portion 8 of the holder 2 and the fitting portion with the cap 12 of the photoelectric conversion element package 3 is bonded and fixed by the adhesive 26. In addition, a gap is formed between the inner peripheral surface 9 of the cylindrical portion 8 other than the adhesive portion 25 and the outer peripheral surface 18 of the cap 12 so that thermal deformation of the cylindrical portion 8 is allowed.

  The optical module 1 of the present embodiment can obtain the same effects as the optical module 1 of the first embodiment described above.

(Third embodiment)
FIG. 4 is a view for explaining the optical module 1 according to the third embodiment of the present invention, and is a longitudinal sectional view schematically showing a state in which the photoelectric conversion element package 3 is attached to the holder 2. In the present embodiment, components that are substantially the same as those of the optical module 1 of the first embodiment described above are denoted by the same reference numerals, and descriptions that are the same as those of the first embodiment are omitted. To do.

  The optical module 1 of the present embodiment is arranged on the inner peripheral side of the cylindrical portion 8 so that the cap end surface 14 of the photoelectric conversion element package 3 is flush with the opening end surface 16 of the cylindrical portion 8 of the holder 2. The cap 12 is fitted with a gap. A hollow disk-shaped ring 27 is fixed to the opening end surface 16 of the cylindrical portion 8 and the outer peripheral end portion of the cap end surface 14 with an adhesive 28. A gap is formed between the inner peripheral surface 9 of the cylindrical portion 8 and the outer peripheral surface 18 of the cap 12 so that thermal deformation of the cylindrical portion 8 is allowed.

  The optical module 1 of the present embodiment can obtain the same effects as the optical module 1 of the first embodiment described above.

(Fourth embodiment)
FIG. 5 is a view for explaining the optical module 1 according to the fourth embodiment of the present invention, and is a longitudinal sectional view schematically showing a state in which the photoelectric conversion element package 3 is attached to the holder 2. In the present embodiment, components that are substantially the same as those of the optical module 1 of the first embodiment described above are denoted by the same reference numerals, and descriptions that are the same as those of the first embodiment are omitted. To do.

  In the optical module 1 of the present embodiment, a protrusion 30 is formed on the inner peripheral surface 9 on the opening end side of the cylindrical portion 8 of the holder 2. On the other hand, on the outer peripheral surface 18 of the cap 12 of the photoelectric conversion element package 3 fitted to the cylindrical portion 8 of the holder 2, a concave portion 31 that engages with the protrusion 30 of the holder 2 is formed. The cylindrical portion 8 of the holder 2 is formed with a plurality of slits 32 extending from the opening end to the root portion along the axis 4 so that the protrusion 30 can be engaged with the concave portion 31 of the cap 12. Can be elastically deformed (expanded deformation). In the optical module 1 having such a structure, the cap 12 is fitted into the cylindrical portion 8 of the holder 2, and the protrusion 30 of the cylindrical portion 8 is engaged with the concave portion 31 of the cap 12, thereby photoelectric conversion to the holder 2. The element module 3 can be detachably fixed.

  In the present embodiment, the axial length (L) of the cylindrical portion 8 is the distance from the apex P1 of the aspherical lens 11 to the protrusion 30. In the present embodiment, a gap is formed between the inner peripheral surface 9 of the cylindrical portion 8 of the holder 2 and the outer peripheral surface 18 of the cap 12 so as to allow thermal deformation of the cylindrical portion 8. ing. Moreover, although this Embodiment illustrated the aspect which forms the protrusion 30 in the cylindrical part 8, and forms the recessed part 31 in the cap 12, it is not restricted to this, A protrusion is formed in the cap 12, and the cylindrical part 8 is formed. A concave portion may be formed in the concave portion, and the projection of the cap 12 and the concave portion of the cylindrical portion 8 may be engaged with each other.

  The optical module 1 of the present embodiment having such a configuration can obtain the same effects as those of the first embodiment described above.

It is a longitudinal cross-sectional view of the holder which comprises the optical module which concerns on the 1st Embodiment of this invention. It is a figure which shows the optical module which concerns on the 1st Embodiment of this invention, Comprising: It is a longitudinal cross-sectional view which shows typically the state which attached the photoelectric conversion element package to the holder. It is a figure which shows the optical module which concerns on the 2nd Embodiment of this invention, Comprising: It is a longitudinal cross-sectional view which shows typically the state which attached the photoelectric conversion element package to the holder. It is a figure which shows the optical module which concerns on the 3rd Embodiment of this invention, Comprising: It is a longitudinal cross-sectional view which shows typically the state which attached the photoelectric conversion element package to the holder. It is a figure which shows the optical module which concerns on the 4th Embodiment of this invention, Comprising: It is a longitudinal cross-sectional view which shows typically the state which attached the photoelectric conversion element package to the holder. It is a figure which shows the cross-sectional shape of an aspherical lens. It is a figure which shows simply the optical connector which uses the optical module of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical module, 2 ... Holder, 3 ... Photoelectric conversion element package, 4 ... Axis, 5 ... Ferrule, 6 ... Optical fiber attachment hole, 8 ... Cylindrical part, 9 ... Inner peripheral surface 11 …… Aspherical lens (lens), 15 …… Hut, 16 …… End face, 18 …… Outer peripheral surface, 23 …… Housing, 24 …… Optical connector

Claims (5)

A ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, and the optical fiber mounting hole in the holder and the A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the cylindrical portion and the optical module that optically couples the ferrule and the photoelectric conversion element package via the lens. And
An optical module, wherein the lens and the holder are integrally formed of plastic. A ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, and the optical fiber mounting hole in the holder and the A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the cylindrical portion and the optical module that optically couples the ferrule and the photoelectric conversion element package via the lens. And
The lens and the holder are integrally formed of plastic,
The photoelectric conversion element package is formed with a flange portion that abuts against the opening end surface of the cylindrical portion, and the flange portion and the opening end surface of the cylindrical portion are bonded and fixed, and the outer peripheral surface of the light source conversion element package and the A gap is provided between the inner peripheral surface of the cylindrical part,
A temperature change amount (Δd2) of a distance (d2) from the top of the lens to the focal point and a temperature change amount (ΔL) of an axial length (L) from the top of the lens to the opening end surface of the cylindrical portion are approximately An optical module characterized by equality. A ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, and the optical fiber mounting hole in the holder and the A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the cylindrical portion and the optical module that optically couples the ferrule and the photoelectric conversion element package via the lens. And
The lens and the holder are integrally formed of plastic,
The cylindrical portion and the photoelectric conversion element package are bonded and fixed at the opening end of the cylindrical portion, and a gap is provided between the outer peripheral surface of the light source conversion element package and the inner peripheral surface of the cylindrical portion,
The temperature change amount (Δd2) of the distance (d2) from the vertex of the lens to the focal point and the temperature change amount (ΔL) of the length (L) in the axial direction from the vertex of the lens to the bonded portion are made substantially equal. An optical module characterized by that. A ferrule is fitted into the optical fiber mounting hole on one end side in the axial direction of the holder, a photoelectric conversion element package is engaged in a cylindrical portion on the other end side in the axial direction of the holder, and the optical fiber mounting hole in the holder and the A smooth curved lens projecting toward the photoelectric conversion element package is disposed between the cylindrical portion and the optical module that optically couples the ferrule and the photoelectric conversion element package via the lens. And
The lens and the holder are integrally formed of plastic,
The opening end of the cylindrical portion and the photoelectric conversion element package are detachably engaged with each other, and a gap is provided between the outer peripheral surface of the light source conversion element package and the inner peripheral surface of the cylindrical portion,
The temperature change amount (Δd2) of the distance (d2) from the apex of the lens to the focal point is substantially equal to the temperature change amount (ΔL) of the axial length (L) from the apex of the lens to the uneven engagement portion. An optical module characterized by that.   An optical connector comprising: the optical module according to any one of claims 1 to 4; and a housing that accommodates and holds the optical module.

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