JP2010217706A - Optical module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module capable of reducing damage generation in packaging parts by making shock waves generated at the collision of a ferrule and a fiber stub relax, when inserting an optical connector. <P>SOLUTION: The optical module includes a package body part mounted with an optical element and a sleeve part 3 for inserting a ferrule 41 of an optical connector, and a fiber stub for optically coupling the optical element; and the ferrule 41 in the sleeve part 3 includes a first fiber stub 21, disposed slidably in the axial direction in the sleeve part 3 and a second fiber stub 22, fixed in the axial direction with respect to the sleeve part 3. The first fiber stub 21 and the second fiber stub 22 are coupled in the axial direction with a buffer member 24. Impact of insertion of an optical connector 40 is relaxed by retracting of the first fiber stub 21 and by the deformation of the buffer member 24. The buffer member 24 is formed with a butyl rubber etc., of a hollow cylindrical shape. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical module including a package main body portion on which an optical element such as a light emitting element is mounted and a sleeve portion into which a ferrule of an optical connector is inserted.

  As an optical module used for optical communication, there is an optical transmission module that transmits signal light, an optical reception module that receives signal light, or an optical transmission / reception module that has both functions of transmission and reception of signal light. These optical modules are mounted on a small pluggable optical transceiver or the like, and are used for high-speed (for example, 10 Gbps) optical communication.

  6A is a diagram showing an example of an optical module (optical transmission module) disclosed in Patent Document 1, for example, and FIG. 6B is a diagram showing an outline of its internal structure. The optical transmission module 1 includes a package body portion 2 on which a light emitting element such as a laser diode is mounted, and a sleeve portion 3 for forming optical coupling with an optical connector of an optical fiber cable serving as an optical transmission path. In the package body 2, a laser diode (LD) 5 and a monitoring photodiode (PD) 6 constituting an optical transmitter are mounted in a box-shaped housing 4 by carrier members 7 and 8.

  The carrier member 7 on which the LD 5 serving as a heat source is mounted is mounted via an electronic cooler 9, and a temperature measuring element 10 for cooling control is mounted. In addition, a circuit element 11 and the like for driving the LD 5 at a high frequency are mounted on the carrier member 7, and a collimating lens 12 for emitting the signal light from the LD 5 to the sleeve portion 3 as collimated light is mounted. A lead pin 13 for connecting to a signal source of an external circuit or a power source is provided on the outer surface or outer end surface of the housing 4.

  The sleeve portion 3 is formed by, for example, a coupling member 16 that houses and holds the condenser lens 14 and the isolator 15 and a sleeve member 17 into which a ferrule of an optical connector is inserted. A fiber stub 19 in which a sleeve 18 into which a ferrule is inserted and an optical fiber element 20 is embedded is inserted into the sleeve member 17. The signal light from the LD 5 is collected and incident on the inner end of the optical fiber element 20 of the fiber stub 19, and the outer end is optically connected to the optical fiber end of the optical connector ferrule.

JP-A-2005-294808

  As shown in FIG. 7, the ferrule 41 of the optical connector 40 is elastically held in a connector housing 42 so as to be movable in the axial direction by a spring 43. When the ferrule 41 is inserted into the sleeve member 17 of the optical module, a physical contact (PC) is established in which the optical fiber 44 of the ferrule 41 contacts the end face of the fiber stub 19 and physically contacts the optical fiber element 20. It is configured as follows.

  However, for some reason, for example, the axis of the ferrule 41 and the sleeve member 17 is shifted or the insertion angle is changed, the insertion may be caught. When the catch occurs, a deterring force against the insertion of the ferrule 41 works and the smooth insertion is suppressed. For this reason, the spring 43 which supports the ferrule 41 in the optical connector 40 is compressed, and the pushing force for insertion into the ferrule 41 is increased.

  When the pushing force of the ferrule 41 becomes larger than the deterring force and the hook for the insertion of the ferrule is released, the ferrule 41 that is biased by the spring 43 jumps out in the axial direction and collides with the fiber stub 19. Since the ferrule 41 and the fiber stub 19 are usually formed of a hard ceramic material such as zirconia, when the ferrule 41 collides with the fiber stub 19, a shock wave composed of high acceleration and high-frequency vibration is generated. This shock wave becomes a pulse wave having an ultrasonic frequency component of 20 kHz to 60 kHz.

  In a high-power optical module as shown in FIG. 6, a two-lens optical system is indispensable for efficiently condensing optical power. In order to configure this optical system, a lens holding structure having a coaxial cylindrical structure and a sleeve holding structure for an optical connector are required. It has been elucidated that the natural frequency of a structure derived from this structure may substantially coincide with the frequency component of the pulse wave.

  For this reason, the generation of the shock wave as described above may propagate through the sleeve portion to excite the casing of the package main body portion and damage the mounted components inside. For example, the end face of the optical fiber 44 held in the ferrule 41, the end face of the optical fiber element 20 held in the fiber stub 19, the optical elements of LD5 and PD6 built in the package main body 2, and the optical element for these optical elements Electronic and electrical parts may be damaged or fall off.

  In order to eliminate such catching of the ferrule 41, there is a method of forming the insertion opening of the sleeve member 17 and the tip end portion of the ferrule 41 with a taper to make the insertion smooth, but the catching cannot be completely eliminated. . In addition, there is a method of increasing the mounting strength of the mounted component, but there is a limit.

  The present invention has been made in view of the above-mentioned circumstances, and provides an optical module that reduces the impact caused by the collision between the ferrule and the fiber stub when the optical connector is inserted, and reduces the occurrence of damage to the mounted components. Objective.

  The optical module of the present invention is an optical module having a package body portion on which an optical element is mounted and a sleeve portion into which a ferrule of an optical connector is inserted, and a fiber stub that optically couples the optical element and the ferrule within the sleeve portion. The fiber stub includes a first fiber stub that is slidably disposed in the axial direction within the sleeve portion, and a second fiber stub that is fixedly disposed in the axial direction with respect to the sleeve portion. The second fiber stub is connected in the axial direction via a buffer member.

  The buffer member may be a hollow cylinder. Further, the first fiber stub and the second fiber stub may hold a common optical fiber element, and the optical fiber element may be slidably held along the through hole of the second fiber stub. Further, the optical module may include a stopper member that restricts deformation of the buffer member in the axial direction, and the stopper member may be configured by a protruding portion provided in the second fiber stub.

  According to the optical module of the present invention, the ferrule collides with the first fiber stub by the insertion of the optical connector, but the first fiber stub slides in the axial direction, and between the first fiber stub and the second fiber stub. Since the shock-absorbing member provided on the stub is deformed, the impact caused by the collision between the ferrule and the fiber stub is mitigated, and the occurrence of damage to the mounted component can be mitigated. Further, since the axial movement of the first fiber stub is defined by the stopper member, the optical fiber element held in common by the first fiber stub and the second fiber stub does not break.

It is a figure which shows an example of the sleeve part of the optical module by this invention. FIG. 3 is a diagram for explaining the action of the buffer member when the ferrule and the fiber stub are coupled in the optical module of FIG. 1. It is a figure which shows an example of the buffer member in this invention. It is a figure for demonstrating the effect | action of the buffer member at the time of the coupling | bonding of a ferrule and a fiber stub in the other example of the optical module by this invention. It is a figure for demonstrating the effect | action of the buffer member at the time of the coupling | bonding of a ferrule and a fiber stub in the further another example of the optical module by this invention. It is a figure which shows the structural example of the conventional optical module. It is a figure for demonstrating the problem which the conventional optical module should solve.

Embodiments of the present invention will be described below with reference to the drawings.
The basic structure of the optical module according to the present invention is the same as that shown in FIG. 6. For example, the package main body 2 on which a light emitting element such as a laser diode is mounted, and an optical fiber cable serving as an optical transmission line. It consists of an optical connector and a sleeve portion for forming optical coupling. In the package body, a laser diode (LD), a monitoring photodiode (PD), and the like constituting an optical transmitter are mounted in a box-shaped housing by a carrier member.

(Embodiment 1)
FIG. 1 is a view showing a sleeve portion of an optical module according to an embodiment of the present invention. The sleeve portion 3 is formed by the coupling member 16 and the sleeve member 17 into which the ferrule 41 of the optical connector 40 is inserted.
The sleeve member 17 includes a sleeve 18, a first fiber stub 21, a second fiber stub 22, a sleeve shell 23, a buffer member 24, an optical fiber element 25, and a stopper member 27. Here, a split sleeve or a precision sleeve is used as the sleeve 18, but it is desirable that the sleeve 18 be a precision sleeve in order to realize smooth movement of the first fiber stub 21 in the optical axis direction.

  In the present embodiment, the first fiber stub 21 and the second fiber stub 22 hold a common (one) optical fiber element 25, and the optical fiber element 25 is attached to the first fiber stub 21 and the second fiber stub 22. Each is fixed. The outer end of the optical fiber element 25 penetrating the first fiber stub 21 is optically connected to the end of the optical fiber 44 of the ferrule 41 of the optical connector 40. Further, the signal light from the LD is collected and incident on the inner end of the optical fiber element 25 that passes through the center hole of the second fiber stub 22. Further, the optical fiber element 25 between the first fiber stub 21 and the second fiber stub 22 is given some bending in advance in order to have flexibility.

FIG. 2 is a view for explaining the action of the buffer member when the ferrule and the fiber stub are coupled. FIG. 2 (A) is a diagram showing the ferrule 41 being inserted, and the relationship between the constituent members will be described in more detail with reference to FIG.
The first fiber stub 21 is slidably disposed in the sleeve 18 in the axial direction, and the second fiber stub 22 is fixedly disposed to the optical module by being fixed to a sleeve shell (not shown), for example. . A buffer member 24 is disposed between the first fiber stub 21 and the second fiber stub 22.

  As shown in the front view of FIG. 2A and the cross-sectional view of FIG. 2B, the buffer member 24 has a hollow cylindrical shape whose outer diameter is smaller than that of the first fiber stub 21 and the second fiber stub 22. However, it is not limited to a hollow cylindrical shape, and may be a plurality of columnar buffer members. In addition, rubber materials such as butyl and silicon are used as the material, but the elasticity of the material is selected so that it deforms against a large force due to impact and the shape returns against the subsequent pressing force. It is desirable.

  The buffer member 24 is fixed to the front and rear first fiber stubs 21 and the second fiber stub 22 with adhesives. Accordingly, the first fiber stub 21 is supported by the buffer member 24 so as to be movable in the axial direction within the sleeve 18. Further, a stopper member 27 that defines a minimum distance between the first fiber stub 21 and the second fiber stub 22 is disposed between the first fiber stub 21 and the second fiber stub 22. The stopper member 27 may be fixed to the first fiber stub 21 or may be fixed to the second fiber stub 22. Further, the stopper member 27 may be provided on the outer peripheral side of the buffer member 24 and fixed to the sleeve.

  When the ferrule 41 is further inserted from the state of FIG. 2A, the PC surface 45 of the ferrule 41 first contacts the PC surface 26 of the first fiber stub 21 as shown in FIG. 2B. . At this time, the first fiber stub 21 resists the pressing force received from the PC surface 45 of the ferrule 41 by the repulsive force of the buffer member 24, and the PC surface 26 of the first fiber stub 21 is ferruled by a predetermined force. The optical fiber 44 and the optical fiber element 25 are optically coupled in contact with the PC surface 45 of 41.

  Further, when the ferrule 41 collides with the first fiber stub 21, the shock absorbing member 24 that cannot resist a large force for a short time due to the impact is compressed and deformed, and the first fiber stub 21 is retracted in the axial direction. The PC surface 45 of the ferrule 41 is received. At this time, the second fiber stub 22 is fixed to the optical module and does not move. However, the impact of the collision of the PC surface 45 of the ferrule 41 is significantly attenuated by the backward movement of the first fiber stub 21 and the deformation of the buffer member 24. And since it is transmitted to the 2nd fiber stub 22 and also the optical module main body side, an impact is not directly transmitted to these members, but is relieved.

  When the ferrule 41 is further inserted by the spring force that urges the ferrule 41, the buffer member 24 is compressed and deformed, and the first fiber stub 21 moves backward. As the distance between the first fiber stub 21 and the second fiber stub 22 becomes smaller, the optical fiber element 25 bends and responds.

  Then, as shown in FIG. 2C, when the first fiber stub 21 comes into contact with the stopper member 27, the movement of the first fiber stub 21 stops. As described above, since the minimum distance between the first fiber stub 21 and the second fiber stub 22 is difficult to be defined only by the repulsive force against the compression deformation of the buffer member 24, the stopper member 27 is disposed, By defining the distance from the two fiber stubs 22, it is possible to prevent the optical fiber from being bent excessively and causing disconnection or excessive loss.

  When the ferrule 41 is removed from the sleeve 18, the first fiber stub 21 is advanced by the restoring force of the buffer member 24 that has been compressed and deformed, so that the state shown in FIG.

(Embodiment 2)
FIG. 4 is a view for explaining the action of the buffer member when the ferrule and the fiber stub are coupled in an optical module according to another embodiment of the present invention.
In this embodiment, as shown in FIG. 4A, the first fiber stub 21 is arranged so as to be slidable in the sleeve 18 in the axial direction, as in the embodiment 1, and the second fiber stub 22 is For example, it is fixedly arranged to the optical module by being fixed to a sleeve shell (not shown). A buffer member 24 is disposed between the first fiber stub 21 and the second fiber stub 22.

  In the present embodiment, the stopper member 28 is configured by a small diameter portion of the second fiber stub 22, in other words, a protruding portion from the second fiber stub 22. The buffer member 24 has a hollow cylindrical shape and is made of a rubber material, and is disposed concentrically outside the stopper member 28. The shape of the buffer member 24 is not limited to the hollow cylindrical shape, and a plurality of columnar shapes may be used. However, when the ferrule 41 is completely inserted, the first fiber stub 21 and the second fiber stub 22 contact each other. It is desirable to select a material whose hardness changes in shape to the extent.

  The fiber element 25 is held by the first fiber stub 21 and the second fiber stub 21, but is fixed (fixed) in the through hole 21 a of the first fiber stub 21, while the protrusion constituting the stopper member 28. It is not fixed in the through hole 22a of the second fiber stub 22 including the portion. Accordingly, the optical fiber element 25 slides along the through hole 22 a of the second fiber stub 22 in conjunction with the sliding of the first fiber stub 21.

  When the ferrule 41 is further inserted from the state of FIG. 4A, the PC surface 45 of the ferrule 41 comes into contact with the PC surface 26 of the first fiber stub 21 as shown in FIG. 4B. At this time, the first fiber stub 21 resists the pressing force received from the PC surface 45 of the ferrule 41 by the repulsive force of the buffer member 24, and the PC surface 26 of the first fiber stub 21 is ferruled by a predetermined force. The optical fiber 44 and the optical fiber element 25 are optically coupled in contact with the PC surface 45 of 41.

  Further, when the ferrule 41 collides with the first fiber stub 21, the shock absorbing member 24 that cannot resist a large force for a short time due to the impact is compressed and deformed, and the first fiber stub 21 is retracted in the axial direction. The PC surface 45 of the ferrule 41 is received. At this time, the second fiber stub 22 is fixed to the optical module and does not move. However, the impact at the time of the collision of the PC surface 45 of the ferrule 41 is remarkably caused by the backward movement of the first fiber stub 21 and the deformation of the buffer member 24. Since it attenuates and is transmitted to the second fiber stub 22 and further to the optical module main body, the impact is mitigated without being directly transmitted to these members.

  When the ferrule 41 is further inserted along the sleeve 18 by the spring force that urges the ferrule 41, the buffer member 24 is compressed and deformed, and the first fiber stub 21 moves backward. As the first fiber stub 21 is retracted, the optical fiber element 25 fixed to the first fiber stub 21 is also retracted. Since the optical fiber element 25 is slidably provided with respect to the second fiber stub 22, no great stress is applied to the optical fiber element 25.

  Further, when the ferrule 41 is inserted, the movement of the first fiber stub 21 stops when the first fiber stub 21 comes into contact with the stopper member 28 as shown in FIG. At this time, the amount of compressive deformation of the buffer member 24 is maximized. Further, since the receding distance of the optical fiber element 25 is also maximized, the optical fiber element 25 is focused on the inner end of the optical fiber element 25 (not shown) on the right side of FIG. The length has been adjusted.

  When the ferrule 41 is removed from the sleeve 18, the first fiber stub 21 is advanced by the restoring force of the buffer member 24 that has been compressed and deformed, so that the state shown in FIG.

(Embodiment 3)
FIG. 5 is a view for explaining the action of the buffer member when the ferrule and the fiber stub are coupled in an optical module according to still another embodiment of the present invention.
In the present embodiment, as shown in FIG. 5A, the first fiber stub 21 is slidably disposed in the sleeve 18 in the axial direction as in the first and second embodiments. For example, 22 is fixedly disposed to the optical module by being fixed to a sleeve shell (not shown). A buffer member 24 is disposed between the first fiber stub 21 and the second fiber stub 22.

  Further, the stopper member 28 is constituted by a small diameter portion of the second fiber stub 22, in other words, a protruding portion from the second fiber stub 22. Since the arrangement configuration of the first fiber stub 21, the second fiber stub 22, the stopper member 28, and the buffer member 24 is the same as that of the second embodiment, the description thereof is omitted.

  In the present embodiment, the fiber elements provided in the first fiber stub 21 and the second fiber stub 22 are not common, and the fiber element 25 a is provided in the through hole 21 a of the first fiber stub 21 to project the stopper member 28. A fiber element 25b is provided in the through hole 22a of the second fiber stub 22 including the portion. The fiber element 25a and the fiber element 25b are fixed (fixed) in the through hole 21a of the first fiber stub 21 and in the through hole 22a of the second fiber stub 22, respectively.

  When the ferrule 41 is further inserted from the state of FIG. 5A, the PC surface 45 of the ferrule 41 comes into contact with the PC surface 26 of the first fiber stub 21 as shown in FIG. 5B. At this time, the first fiber stub 21 resists the pressing force received from the PC surface 45 of the ferrule 41 by the repulsive force of the buffer member 24, and the PC surface 26 of the first fiber stub 21 is ferruled by a predetermined force. In contact with the PC surface 45 of 41, optical coupling between the optical fiber 44 and the optical fiber element 25a is performed.

  Further, when the ferrule 41 collides with the first fiber stub 21, the shock absorbing member 24 that cannot resist a large force for a short time due to the impact is compressed and deformed, and the first fiber stub 21 is retracted in the axial direction. The PC surface 45 of the ferrule 41 is received. At this time, the second fiber stub 22 is fixed to the optical module and does not move. However, the impact at the time of the collision of the PC surface 45 of the ferrule 41 is remarkably caused by the backward movement of the first fiber stub 21 and the deformation of the buffer member 24. Since it attenuates and is transmitted to the second fiber stub 22 and further to the optical module main body, the impact is mitigated without being directly transmitted to these members.

  When the ferrule 41 is further inserted along the sleeve 18 by the spring force that urges the ferrule 41, the buffer member 24 is further compressed and deformed, and the first fiber stub 21 moves backward, as shown in FIG. Furthermore, when the PC surface 29 of the first fiber stub 21 contacts the PC surface 30 of the stopper member 28, the movement of the first fiber stub 21 stops.

At this time, optical coupling between the fiber element 25a provided in the first fiber stub 21 and the fiber element 25b provided in the second fiber stub 21 is performed, and as a result, optical coupling between the optical fiber 44 and the optical fiber element 25b occurs. Done.
For this reason, it is desirable that the buffer member 24 is selected from a material whose hardness changes so that the first fiber stub 21 and the stopper member 28 come into contact with each other when the insertion of the ferrule 41 is completed. The impact when the PC surface 29 of the first fiber stub 21 abuts against the PC surface 30 of the stopper member 28 is sufficient because the movement of the first fiber stub 21 is decelerated by the compression deformation of the buffer member 24. Will be attenuated.

  When the ferrule 41 is removed from the sleeve 18, the first fiber stub 21 is advanced by the restoring force of the buffer member 24 that has been compressed and deformed, so that the state shown in FIG.

DESCRIPTION OF SYMBOLS 1 ... Optical module, 2 ... Package main-body part, 3 ... Sleeve part, 4 ... Case, 5 ... Laser diode (LD), 6 ... Photodiode, 7, 8 ... Carrier member, 9 ... Electronic cooler, 10 ... Measurement Temperature element, 11 ... Circuit element, 12 ... Collimating lens, 13 ... Lead pin, 14 ... Condensing lens, 15 ... Isolator, 16 ... Connecting member, 17 ... Sleeve member, 18 ... Sleeve, 19 ... Fiber stub, 20, 25 ... Optical fiber element, 21 ... first fiber stub, 22 ... second fiber stub, 23 ... sleeve shell, 24 ... buffer member, 26, 29, 30, 45 ... PC surface, 27,28 ... stopper member, 40 ... optical connector , 41 ... ferrule, 42 ... connector housing, 43 ... spring, 44 ... optical fiber.

Claims (7)

An optical module comprising a package body portion on which an optical element is mounted and a sleeve portion into which a ferrule of an optical connector is inserted,
A fiber stub that optically couples the optical element and the ferrule in the sleeve portion, the fiber stub being disposed in the sleeve portion so as to be slidable in the axial direction and the sleeve portion. An optical module comprising: a second fiber stub fixedly disposed in the axial direction, wherein the first fiber stub and the second fiber stub are coupled in the axial direction via a buffer member.   The optical module according to claim 1, wherein the buffer member has a hollow cylindrical shape.   The optical module according to claim 1, further comprising a stopper member that defines a minimum axial distance between the first fiber stub and the second fiber stub.   The optical module according to claim 3, wherein the stopper member is constituted by a protrusion provided on the second fiber stub.   The optical module according to claim 1, wherein the first fiber stub and the second fiber stub hold a common optical fiber element.   6. The optical module according to claim 5, wherein the common optical fiber element is slidably held along the through hole of the second fiber stub.   5. The optical module according to claim 4, wherein each of the first fiber stub and the second fiber stub has an optical fiber element.

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