JP2011066402A - Optical transmitter module and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmitter module that is a ceramic package type optical transmitter module, facilitates the installation and alignment of a lens and an optical filter, and reduces the cost, and to provide a method of manufacturing the same. <P>SOLUTION: In the optical transmitter module, a signal light output from a laser diode 13 is concentrated by an optical lens 16 and reflected by an optical filter 15, and then emitted into a sleeve which connects an optical fiber. The optical lens 16 and the optical filter 15 are assembled into a one-piece filter lens carrier 14, and mounted within a ceramic package 1 together with the laser diode. The laser diode 13 can be mounted through an electronic cooling machine 11 which regulates the temperature. The filter lens carrier 14 is mounted so as to be supported on a multilayer substrate 1b of the ceramic package 1, or to be supported on the electronic cooling machine 11. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a ceramic package type optical transmission module used for optical communication and a method for manufacturing the same.

  An optical transmission module used for optical communication uses light from a laser diode (LD) as signal light. The signal light is collected by a lens and is transmitted to an optical fiber for communication through an optical window of a package. Are connected. In an optical transmission module equipped with a temperature adjustment device (hereinafter referred to as TEC), a TEC is fixed on the base of a package, and a laser diode (hereinafter referred to as LD) is mounted on the TEC via a carrier. Further, the signal light is emitted in a predetermined direction by bending the direction of the optical axis by using a prism or an optical filter as necessary.

  As a form of the optical transmission module, there are those called a CAN package type and a butterfly type. The CAN package type optical transmission module has, for example, a configuration in which an optical window is provided on the upper end side of a circular metal package that accommodates an LD, and lead pins extend from the lower end side (see, for example, Patent Document 1). . The butterfly type optical transmission module is one size larger than the CAN package type, and has an optical window provided at the front end portion of the rectangular parallelepiped shape, and lead pins extend from the side portion and the rear end portion (for example, Patent Document 2).

JP 2004-2537779 A JP 2005-236298 A

As shown in XFP and SFPplus, which are standards for removable optical transceivers, optical transceivers are becoming smaller, lower power, and lower in cost. Has been.
Recently, in addition to the optical modules having the forms shown in Patent Documents 1 and 2, a smaller and cheaper ceramic package type optical transmission module has been considered. In this case, the space in the package is greatly limited as compared to the above. For this reason, there are various things such as the installation of lenses mounted in relation to the arrangement of LDs, the arrangement of optical filters or reflecting surfaces for bending the optical axis in a predetermined direction, alignment of optical systems, ease of mounting, cost, etc. Consideration from the point of view is required.

  The present invention has been made in view of the above-described points, and is a ceramic package type optical transmission module, in which a lens and an optical filter can be easily installed and aligned, and the cost can be reduced. And its manufacturing method.

  An optical transmission module according to the present invention is an optical transmission module in which signal light output from a laser diode is collected by an optical lens, reflected by an optical filter, and emitted into a sleeve connecting optical fibers. The lens and the optical filter are mounted on a single filter lens carrier and mounted in a ceramic package together with a laser diode.

  The laser diode can be mounted via an electronic cooler that adjusts the temperature. The filter lens carrier is mounted so as to be supported on the laminated substrate of the ceramic package or to be supported on the electronic cooler. The optical lens is an aspherical lens or a spherical lens, and the optical filter is formed by vapor-depositing a total reflection film on a glass or ceramic surface. Further, instead of the optical filter, the reflecting surface of the filter lens carrier may be directly plated with Au.

Further, the method of manufacturing an optical transmission module according to the present invention includes: an optical transmission module in which signal light output from a laser diode is collected by an optical lens, reflected by an optical filter, and emitted into a sleeve connecting optical fibers. A manufacturing method of
The optical lens and the optical filter are positioned and mounted on a single filter lens carrier, and then the laser diode and the filter lens carrier are positioned and mounted in a ceramic package.

  According to the present invention, an optical lens and an optical filter can be automatically positioned and fixed to a single filter lens carrier, and installation and alignment with respect to a ceramic package having variations in manufacturing is easy. Thus, a small and accurate optical transmission module can be obtained.

It is a figure which shows an example of the external appearance of the optical transmission module of this invention. It is a figure explaining the component mounting form in the ceramic package by this invention. It is a figure explaining the mounting example of the lens which has a square holding | maintenance part, and an optical filter. It is a figure explaining the mounting example of the lens which has a circular holding | maintenance part, and an optical filter. It is a figure explaining the example of mounting of the ball lens and optical filter which do not have a holding part. It is a figure explaining the other example of mounting of the lens which has a square holding part, and an optical filter. It is a figure explaining the other example of mounting of the lens or spherical lens which has a circular holding part, and an optical filter. It is a figure explaining the other mounting example of the lens which has a square holding | maintenance part, and an optical filter. It is a figure explaining the other mounting example of the lens or spherical lens which has a circular holding | maintenance part, and an optical filter. It is a figure explaining another example of mounting of a lens which has a circular holding part, and an optical filter. It is a figure which shows an example of the mounting method of the lens which has a circular holding | maintenance part. It is a figure which shows an example which aligns and mounts a filter lens carrier in a ceramic package.

  In the optical transmission module according to the present invention, for example, as shown in FIG. 1, an optical fiber is inserted and connected to a lid 2 for sealing the inside of the package on the upper surface of a ceramic package 1 and a joint sleeve 3 to the lid 2. The sleeve 4 is connected. The lid 2 is integrally formed with a holder portion 2a fitted to the joint sleeve 3 at the center on the upper surface side, and has an optical window (not shown) for transmitting signal light. It is sealed and fixed.

  The joint sleeve 3 aligns the optical path length with the end of the optical fiber by adjusting the position of the holder portion 2a in the Z-axis direction, and adjusts the position of the joint surface 3a with the sleeve 2 in the XY direction to adjust the end of the optical fiber. Alignment with respect to the positional deviation is performed. After the alignment between the signal light and the end of the optical fiber is performed via the joint sleeve 3, the respective adjustment portions are fixed by an adhesive or welding. The sleeve 4 is provided with a receptacle part 4a to which an optical connector attached to the end of the optical fiber is fitted and connected, a support part 4b to be held and fixed to an optical transceiver or the like.

  As shown in FIG. 2, the ceramic package 1 is, for example, a laminate in which a rectangular bottom ceramic substrate 1a and a plurality of ceramic rectangular frame-like package frames 1b are sequentially laminated, and a metal frame 1c is arranged at the uppermost end. A structure can be used. Note that FIG. 2 is a view in which a part of the package wall is removed in order to make the structure easy to understand. Further, the ceramic package 1 is formed in a box shape having a length of about a (vertical a = 5.5 mm, a horizontal b = 4.5 mm, a height c = 2.5 mm) as shown in FIG. Mounted components to be described later are mounted inside.

  The bottom ceramic substrate 1a of the ceramic package 1 has a function as a stem serving as a support for an electronic component mounted in the package, a base of the package, and an electrical connection port to an external circuit. The package frame 1b can set the package height c to a desired value depending on the number of stacked layers. The package frame 1b located in the middle is, for example, a signal supply board 1d in which conductors and pads for power supply and electrical signals are formed to electrically connect electronic components mounted in the package, or electronic components The component mounting board 1e provided with a region for mounting can be obtained. The metal frame 1c is for fixing the metal lid 2 shown in FIG. 1 by welding or soldering, and may be omitted when the resin is bonded.

  The storage chamber 10 of the ceramic package 1 is formed in a rectangular shape. For example, an electronic cooler 11 (hereinafter referred to as a TEC) is mounted on the bottom ceramic substrate 1a (or a metal heat dissipation substrate). The TEC 11 has a heat absorbing plate 11b on the upper surface side of an electronic cooling element 11a such as a Peltier device, and has a heat radiating plate 11c on the lower surface side, and is arranged so that the heat radiating plate 11c contacts the bottom ceramic substrate 1a. An LD 13 is mounted on the heat absorbing plate 11b via an LD carrier 12 (also referred to as a submount). Note that the TEC 11 is not mounted in a non-temperature-controlling optical transmission module that does not perform temperature control of the LD.

  The signal light from the LD 13 is emitted in the direction parallel to the mounting surface, then reflected in the orthogonal direction and coupled to the optical fiber, and the monitor light is extracted from the back side opposite to the signal light emission side. The light is received by a monitoring photodiode (hereinafter referred to as monitor PD). The monitor PD (not shown) is mounted so as to be able to receive the back light of the LD 13 using, for example, the component mounting board 1e incorporated in the above-described package frame by stacking. In addition, electric circuit wiring such as the power source and signal lines of the monitor PD and LD 13 is formed using the signal supply substrate 1d.

  The signal light from the LD 13 is condensed or converted into parallel light by the optical lens 16, reflected by the optical filter 15, and emitted to the end of the optical fiber in the sleeve 4 of FIG. The optical filter 15 may be one that reflects light of a predetermined wavelength and transmits light of other wavelengths (a multiplexing / demultiplexing filter, also referred to as a WDM filter). In the case where only the signal light is reflected, the optical filter 15 may be one in which a total reflection film is deposited on a glass surface. As the reflection film, a highly reliable Ag vapor deposition film is used, and the reflectance can be 98% or more.

  In addition, as the optical filter 15 for reflecting the signal light, a ceramic material plated with Au can be used. As the ceramic material at this time, the same ceramic material as that used as the carrier material on which the LD is mounted can be used. Further, the mounting surface of the inclined optical filter of the filter lens carrier to be described later can be directly plated with Au to replace the optical filter.

The optical lens 16 may be a lens having a configuration in which the outer peripheral holding portion is square or circular and has an aspherical lens or a spherical lens on the center side of the holding portion. An aspherical lens is used in the high-power specification optical transmission module, and a spherical lens is used in the low-output specification optical transmission module.
The optical lens 16 may be arranged between the optical filter 15 and the optical fiber, but the height of the ceramic package 1 increases due to the arrangement space. Further, when using an LD with a large numerical aperture (NA), it is necessary to place the lens as close to the LD as possible, and when high coupling efficiency (-2 dB or more) of the lens is required, the LD 13 and the optical filter 15 It is desirable to arrange the optical lens 16 between them.

  In the present invention, by disposing the optical lens 16 between the LD 13 and the optical filter 15, the ceramic package 1 can be further downsized with high coupling efficiency. And in said structure, by mounting the optical filter 15 and the optical lens 16 on the common carrier which consists of a single body, these installation and alignment are made easy, and a small and highly accurate optical module is obtained. Is possible. In the present invention, a common carrier on which the optical filter 15 and the optical lens 16 are mounted will be referred to as a filter lens carrier.

3 to 5 are diagrams showing examples in which an optical filter and various optical lenses are mounted on the filter lens carrier 14, FIG. 3 shows an example in which a holding part is mounted with a square lens, and FIG. 4 shows a holding part. Shows an example of mounting a circular lens, and FIG. 5 shows an example of mounting a spherical lens with the holding portion omitted.
The filter lens carrier 14 includes a horizontal portion 14a and a vertical portion 14b, and can be formed of metal, ceramic, or resin by molding / pressing or machining. The filter lens carrier 14 is formed with an outer shape of, for example, about (vertical e = 1.6 mm, horizontal g = 2.2 mm, height f = 1.0 mm).

  The lower surface (back surface) of the horizontal portion 14a is used as a reference surface as the first surface 20a, and the filter lens carrier 14 is bonded to the mounting surface of the ceramic package 1 to adjust the distance between the LD and the lens as will be described later. Used for. In the vertical portion 14b, a second surface 20b having an angle of, for example, 45 ° with respect to the first surface 20a is formed. An optical filter 15 that reflects (bends) the signal light is bonded and fixed to the second surface 20b with an ultraviolet curable (UV) resin or the like.

  When the base material of the optical filter 15 is made of ceramic, AuSn solder is vapor-deposited on the back surface of the optical filter 15, and Ni / Au plating is applied to the second surface 20b, thereby optically. The filter 15 can be fixed using an automatic die bonder in the same manner as the LD. In addition, it can be fixed with a solder material by reflow soldering using a dedicated jig, and can be assembled at low cost without being costly for processing parts. The optical filter 15 is formed in a square of about (vertical h = 1.5 mm, horizontal i = 1.5 mm), for example.

  A third surface 20c parallel to the first surface 20 is formed on the upper surface side of the horizontal portion 14a. Various lenses 16a to 16c, which will be described later, are placed on the third surface 20c, and are bonded and fixed with UV resin or the like. This bonding and fixing can be performed off-line together with the optical filter 15 before the filter lens carrier 14 is mounted on the ceramic package 1.

  As shown in FIG. 3, when using a rectangular lens 16a as the holding portion, one side is placed on the third surface 20c, and its end portion is aligned in parallel with the front end edge of the horizontal portion 14a to perform positioning in the front-rear direction. What is necessary is just to adhere and fix. In this case, in order to position the lens 16a at the center position, a stop jig for preventing the movement of the lens in the side surface direction may be disposed, or a groove or a protrusion is formed on the third surface 20c. It may be provided and positioned at the center position. The lens 16a is formed with an outer shape of, for example, a height (k = 1.0 mm, width j = 1.0 mm, thickness m = 0.8 mm).

  FIG. 4 shows a case where a lens 16b having a circular holding portion is used. For example, a shallow V-shaped groove 20d is preferably provided in the center of the third surface 20c of the horizontal portion 14a. The side surface of the lens 16b may be placed in the groove 20d, and the end portion may be aligned and fixed to the front end edge of the horizontal portion 14a, and the lens 16b is positioned at the center position by the groove 20d. The lens 16b is formed with an outer shape of about (outer diameter p = 1.0 mmΦ, thickness n = 0.8 mm), for example.

  FIG. 5 shows a case where a spherical lens 16c having no holding portion is used. As in the case of FIG. 4, it is preferable to provide a shallow V-shaped groove 20d at the center of the third surface 20c of the horizontal portion 14a. . The lens 16b is placed in the groove 20d, and the position in the front-rear direction may be bonded and fixed by arranging a stop jig for preventing the movement of the lens on the front end side of the horizontal portion 14a. The lens 16c is formed of, for example, a sphere having a diameter of about (q = 1.5 mmΦ).

  6 to 7 show other embodiments, FIG. 6 shows an example using a lens having a square holding part, FIG. 7A shows an example using a lens having a circular holding part, and FIG. (B) shows an example using a spherical lens having no holding portion. In this example, the filter lens carrier 17 is composed of a horizontal portion 17a and a vertical portion 17b as in the examples of FIGS. 3 to 5, and metal, ceramic, and resin are formed with the same external dimensions by molding, pressing, or machining. can do. Although this example is different from the examples of FIGS. 3 to 5 in that the horizontal portion 17a is formed by a pair of arms, other configurations can be the same.

  The lower surface (back surface) of the pair of arms forming the horizontal portion 17a is used as a reference surface as the first surface 20a, as in the examples of FIGS. 3 to 5, and the filter lens carrier 17 is bonded to the mounting surface of the ceramic package 1. Thus, it is used for alignment of the optical path in the package. In the vertical portion 17b, a second surface 20b having an angle of, for example, 45 ° with respect to the first surface 20a is formed. An optical filter 15 that reflects (bends) the signal light is fixed to the second surface 20b as in the examples of FIGS.

  As shown in FIG. 6C, the horizontal portion 17a is placed on the jig 30, and the insides of the pair of arms serve as the fourth surface 20e. The distance r between the fourth surfaces 20e is, for example, slightly larger (about +0.02 mm) than the width of the lens 16a. The lens 16 a is positioned by placing the lens 16 a on the jig 30 so that the front end of the lens coincides with the tip of the horizontal portion 17 a between the opposing fourth surfaces 20 e of the pair of arms. In this state, an adhesive is applied between the lens 16a and the fourth surface 20e to fix them.

  FIG. 7A shows a case where a lens 16b having a circular holding portion is used. As in FIG. 6, a jig base is placed on the lower surface of the horizontal portion 17a composed of a pair of arms, and the lens 16b is formed inside the pair of arms. Is placed between the formed fourth surfaces 20e. Then, the front end of the lens is aligned with the front end of the horizontal portion 17a and positioned by the fourth surface 20e, and an adhesive is applied between the lens 16b and the fourth surface 20e to fix them.

  FIG. 7B shows a case where a spherical lens 16c having no holding portion is used. As in FIG. 6, a jig base is placed on the lower surface of the horizontal portion 17a composed of a pair of arms, and the lens is formed inside the pair of arms. Is placed between the formed fourth surfaces 20e. Then, using a stop jig or the like that regulates the position of the tip from the horizontal portion 17a, an adhesive is applied between the lens 16c and the fourth surface 20e to be bonded and fixed.

  8 to 9 show other examples, FIG. 8 shows an example using a lens having a square holding part, FIG. 9A shows an example using a lens having a circular holding part, and FIG. (B) shows an example using a spherical lens having no holding portion. In this example, the filter lens carrier 18 includes a horizontal portion 18a and a vertical portion 18b as in the examples of FIGS. 6 to 7, and metal, ceramic, and resin can be formed by molding / pressing or machining. Although this example is different from the examples of FIGS. 6 to 7 in that an overhanging part 20f that restricts the axial position of the lens is formed on the horizontal part 18a composed of a pair of arms, other configurations may be the same. it can.

  The lower surfaces (back surfaces) of the pair of arms forming the horizontal portion 18a are used as a reference surface as the first surface 20a, and the filter lens carrier 18 is bonded to the mounting surface of the ceramic package 1 to adjust the optical path in the package. Used for the heart. In the vertical portion 18b, a second surface 20b having an angle of, for example, 45 ° with respect to the first surface 20a is formed. An optical filter 15 that reflects (bends) signal light is attached and fixed to the second surface 20b in the same manner as in the examples of FIGS.

  As shown in FIG. 8, the horizontal portion 18a is placed on a jig in the same manner as in the example of FIG. 6C, and the inside of the pair of arms serves as the fourth surface 20e. The interval between the fourth surfaces 20e is slightly larger than the width of the lens 16a, as in the example of FIG. In this example, an overhanging portion 20f that projects from the fourth surface 20e is formed, and the front end surface is inserted between the opposing fourth surfaces 20e of the pair of arms so as to coincide with the front end of the horizontal portion 17a. And it positions by making the back surface of the lens 16a contact | abut to the overhang | projection part 20f. In this state, an adhesive is applied between the lens 16a and the fourth surface 20e to fix them.

  FIG. 9A shows a case where the lens 16b has a circular holding portion. Like FIG. 8, a jig base is placed on the lower surface of the horizontal portion 18a composed of a pair of arms, and the cylindrical lens is placed inside the pair of arms. It is placed between the fourth surfaces 20e formed in the above. And it positions by making it contact | abut to the overhang | projection part 20f. In this state, an adhesive is applied between the lens 16c and the fourth surface 20e to fix them.

  FIG. 9B shows a case where a spherical lens 16c having no holding portion is used. As in FIG. 8, a jig base is placed on the lower surface of the horizontal portion 18a composed of a pair of arms, and the spherical lens is placed inside the pair of arms. It is placed between the formed fourth surfaces 20e. And it positions by making a spherical lens contact | abut to the overhang | projection part 20f. In this state, an adhesive is applied between the ball lens 16c and the fourth surface 20e to fix them.

  FIG. 10 is a diagram showing another example of a filter lens carrier and an example in which an optical filter and a lens are used for the carrier. The filter lens carrier 19 of this example has a shape similar to the example of FIGS. 6 to 7, and is shown as an example using the lens 16b having the circular holding portion of FIG. As shown in FIG. 10, the filter lens carrier 19 includes a pair of side wall portions 19a and an intermediate portion 19b between the side wall portions, and in the same manner as in the above-described example, metal, ceramic, and resin are formed, pressed, or machined. Can be formed.

  The lower surface of the filter lens carrier 19 is a first surface 20a that is a reference surface for mounting on the ceramic package, as in the above-described example, and is placed on the mounting surface of the ceramic package to adjust the optical path in the package. Used for the heart. For example, a second surface 20b having an angle of 45 ° with respect to the first surface 20a is formed in the intermediate portion 19b, and an optical filter that reflects signal light is formed on the second surface 20b. 15 is pasted and fixed. The inner wall of the side wall portion 19a is a fourth surface 20e for adhering and fixing the lens 16b in the form as shown in FIG. 7A, and the upper portion of the fourth surface 20e is an inner wall surface whose thickness is reduced. A stepped portion 21b is formed by 21a.

  The fourth surface 20e of this example is divided by the stepped portion 21b, and the adhesive 22 is applied to the portion that contacts the holding portion of the lens 16b. The filter lens carrier 19 is placed on a jig, and the lens 16b is positioned between the stepped portion 21b and the lower fourth surface 20e in the same form as in FIG. 7A, and is placed on the front end of the side wall 19a. The front end of the lens is matched to be bonded by the adhesive 22.

  FIG. 11 is a diagram illustrating an example of a method of mounting the lens 16b on the filter lens carrier 19 described in FIG. FIG. 11A shows an example in which an adhesive 22 is applied to the fourth surface 20e. For example, an adhesive made of an ultraviolet curable resin is supplied from a nozzle 31 of a dispenser (in the form similar to a syringe). The nozzle 31 is moved so as to be in contact with the thinned inner wall surface 21a of the side wall portion 19a, and is pushed down to abut the tip portion against the stepped portion 21b. In this state, a predetermined amount of the adhesive material 22 is applied to the fourth surface 20e below the step portion 21b. The adhesive 22 can remain in the applied position without dripping down on the surface of the fourth surface 20e due to viscosity.

  Subsequently, as shown in FIG. 11B, the filter lens carrier 19 to which the adhesive 22 is applied is the jig 30 shown in FIG. 6C assuming a mounting surface such as TEC or the jig described next. The lens 16b is set between the fourth surfaces 20e of the side wall 19a. The lens 16b is set so that the front surface thereof substantially coincides with the front surface of the side wall portion 19a, and is temporarily held so as to push the adhesive material 22 away. At this stage, the adhesive 22 is in an uncured state, and the lens 16b is not completely fixed and is movable.

  The lens 16b accommodated in the filter lens carrier 19 is placed on a jig and positioned in the vertical direction (height direction position) orthogonal to the optical axis, and orthogonal to the optical axis between the fourth surfaces 20e. Positioning in the horizontal direction (lateral position) is performed. Note that the gap between the fourth surface 20e and the holding surface of the lens 16b is set to about 5 μm, and even if a tilt within this range occurs, there is no effect in an allowable range, and high-accuracy positioning is mechanically performed. Yes.

  The lens 16 b is positioned in the axial direction on the jig 32 shown in FIG. 11C in a state where the lens 16 b is housed and temporarily held in the filter lens carrier 19. The lens 16b may be stored and set with the filter lens carrier 19 placed on the placement surface 32a of the jig 32. The jig 32 has a mounting surface 32a that contacts the first surface (reference surface) 20a of the filter lens carrier 19 and an abutting surface 32b that contacts the front end of the side wall portion 19a. The abutting surface 32b includes a lens 16b. A circular hole 32c is provided so that the swelled portion of the hole does not hit.

  The filter lens carrier 19 placed on the placement surface 32 a of the jig 32 is urged so that the front end of the side wall portion 19 a is in contact with the abutting surface 32 b by the pressing member 33. Then, vacuuming is performed through the circular hole 32c formed in the abutting surface 32b, and the lens 16b is sucked. The lens 16b moves so that the central bulge portion enters the circular hole 32c, the flat surface portion around the lens 16b contacts the abutting surface 32b, and the flat surface portion around the lens is urged by the pressing member 33 to abut the lens 16b. It is aligned with the front end of the filter lens carrier 19 in contact with the surface 32b, and the axial position of the lens 16b is set. In this aligned state, the lens 16b is bonded and fixed by irradiating the adhesive 22 with ultraviolet rays and solidifying.

  The example of FIGS. 6 to 10 described above requires the use of a jig 30 as shown in FIG. 6C, but the height of the filter lens carrier is higher than that of the examples of FIGS. f (see FIG. 3) can be reduced. However, instead of using the jig 30, horizontal portions 17a and 18a comprising a pair of arms shown in FIGS. 6 to 9 are formed on the upper surface of the horizontal portion 14a shown in FIGS. Thus, it may be uniquely positioned with respect to the lateral direction of the lens and further to the front-rear direction.

  As shown in FIGS. 3 to 11, the optical filter 15 and the lenses (16a, 16b, 16c) can be pre-positioned and fixed to the filter lens carrier (14, 17, 18, 19) offline. . In addition, the optical filter 15 can be automatically positioned and fixed by the inclined second surface 20b, and the lenses (16a, 16b, 16c) are also mechanically positioned and fixed by using a jig. can do.

  The filter lens carrier (14, 17, 18, 19) on which the optical filter 15 and the lenses (16a, 16b, 16c) are mounted is then placed in the storage chamber 10 of the ceramic package 1 as described with reference to FIG. Installed. When the TEC 11 is mounted in the storage chamber 10, it may be mounted together with the LD carrier 12 on the heat absorbing plate 11 b. However, in this case, since the heat dissipation capacity of the TEC increases and the power consumption increases, in order to avoid this, the filter lens carrier is mounted floating from the TEC 11. As a method of mounting by floating from the TEC 11, for example, an overhanging portion on which a filter lens carrier is placed in an appropriate package frame 1b is provided and supported by the overhanging portion.

  Further, the filter lens carrier (14, 17, 18, 19) on which the optical filter 15 and the lenses (16a, 16b, 16c) are mounted has an observation device such as a CCD camera directly above the ceramic package 1, and an LD end face. Measure the distance between the lens and the opposite end face of the lens. Then, the first surface 20a of the filter lens carrier is moved and adjusted with respect to the mounting surface so that the distance becomes a predetermined value. Thereby, alignment on the optical path in the ceramic package 1 is completed, and the upper surface of the package is sealed by the lid 2.

  FIG. 12 is a diagram illustrating an example of a jig (collet) 34 that holds the filter lens carrier 19 on which the optical filter 15 and the lens 16 b are mounted and is mounted in the ceramic package 1. The collet 34 includes a pair of support legs 34 a formed at predetermined intervals and a pressing member 34 b that presses the back surface of the filter lens carrier 19. The support leg 34a is provided with a recess having a vertical surface 34c that abuts the front end of the side wall 19a of the filter lens carrier 19 and a horizontal surface 34d that abuts the upper end of the side wall 19a.

  The collet 34 urges the back surface of the filter lens carrier 19 with the pressing member 34b so that the front end of the side wall portion 19a of the filter lens carrier 19 abuts on the vertical surfaces 34c of the support legs 34a on both sides, and the filter lens carrier 19 Is held between the vertical surface 34c and the pressing member 34b. Further, the lower surface (reference surface) of the filter lens carrier 19 is prevented from rising from the mounting surface in the ceramic package 1 by contacting the upper end of the side wall portion 19a of the filter lens carrier 19 with the horizontal surface 34d of the support legs 34a on both sides. . Then, the collet 34 is moved in the XY direction to perform alignment on the optical path.

  Although the example in which the lens 16b having a circular holding portion is mounted on the filter lens carrier 19 has been described with reference to FIG. 12, by changing the shape of the support leg 34a, other filter lens carriers (14, 17, 18) and Also, the lens 16a having a flat holding part or the spherical lens 16c having no holding part can be used.

  In the above-described embodiment, the angle of the second surface 20b on which the optical filter 15 is mounted is described as 45 °. However, the present invention is not limited to this. The end face of the optical fiber is usually cut obliquely (5 to 7 °) with respect to its optical axis in order to prevent the light reflected by the end face from entering the LD again and becoming noise light. The incident angle of light that gives the optimum coupling efficiency to the end face of the oblique cut is about 2.8 °. Since the incident angle of the light reflected by the optical filter 15 on the mounting surface gives only 0 °, when the angle is 45 °, the optical axis (center axis) of the lens 16 is offset with respect to the optical axis of the LD 13, and the LD 13 Is incident on the lens 16 obliquely, and the angle of the light emitted from the lens 16 is made to be at an angle with respect to the optical axis of the lens 16, thereby realizing the optimum incident angle.

However, by setting the angle of the mounting surface of the optical filter 15 to 46.4 ° or 43.6 °, the optical axis of the LD 13 and the optical axis of the lens 16 are matched, and the light emitted from the lens 16 has an angle. In this case, the optical axis of the light reflected by the optical filter 15 can be tilted with respect to the optical axis of the optical fiber. While maintaining the optical axis of the optical fiber in the vertical direction and the optical axes of the LD 13 and the lens 16 in the horizontal direction, the incident angle with respect to the optical fiber having the oblique cut end surface can be optimized.
The mounting surface angles of 46.4 ° and 43.6 ° are angles corresponding to the case where the angle of the fiber end surface is inclined 6 ° with respect to the optical axis, and the end surface angle is 5 to 7 °. When it is adjusted within the range, it may be changed according to the end face angle.

DESCRIPTION OF SYMBOLS 1 ... Ceramic package, 1a ... Bottom ceramic board, 1b ... Package frame, 1c ... Metal frame, 1d ... Signal supply board, 1e ... Component mounting board, 2 ... Lid, 2a ... Holder part, 3 ... Joint sleeve, 3a ... Joining Surface, 4 ... Sleeve, 4a ... Receptacle part, 4b ... Support part, 10 ... Storage chamber, 11 ... Electronic cooler (TEC), 11a ... Electronic cooling element, 11b ... Heat absorption plate, 11c ... Heat dissipation plate, 12 ... LD carrier , 13: Laser diode (LD), 14, 17, 18, 19 ... Filter lens carrier, 14a, 17a, 18a ... Horizontal portion, 14b, 17b, 18b ... Vertical portion, 15 ... Optical filter, 16 ... Optical lens, 16a ... Square lens, 16b ... Cylindrical lens, 16c ... Spherical lens, 19a ... Side wall part, 19b ... Intermediate part, 20a ... First surface, 20b 2nd surface, 20c ... 3rd surface, 20d ... V-shaped groove, 20e ... 4th surface, 20f ... Overhang part, 21a ... Inner wall surface, 21b ... Stepped part, 22 ... Adhesive, 30, 32 ... Jig, 31 nozzle, 32a ... Placing surface, 32b ... Abutting surface, 32c ... Circular hole, 33 ... Pressing member, 34 ... Collet, 34a ... Support leg, 34b ... Pressing member, 34c ... Vertical surface, 34d ... horizontal.

Claims (9)

An optical transmission module that outputs signal light output from a laser diode, reflected by an optical filter after being collected by an optical lens, and emitted into a sleeve connecting an optical fiber,
The optical transmission module, wherein the optical lens and the optical filter are mounted on a single filter lens carrier and mounted in a ceramic package together with the laser diode.   The optical transmission module according to claim 1, wherein the laser diode is mounted via an electronic cooler that performs temperature adjustment.   The optical transmission module according to claim 1, wherein the filter lens carrier is mounted so as to be supported on a laminated substrate of the ceramic package.   The optical transmission module according to claim 2, wherein the filter lens carrier is mounted so as to be supported on the electronic cooler.   The optical transmission module according to claim 1, wherein the optical lens is an aspheric lens.   The optical transmission module according to claim 1, wherein the optical lens is a spherical lens.   The optical transmission module according to claim 1, wherein the optical filter is formed by depositing a reflective film on a glass or ceramic substrate.   The optical transmission module according to claim 1, wherein the optical filter is formed by directly performing Au plating on a reflection surface of the filter lens carrier. A method of manufacturing an optical transmission module in which signal light output from a laser diode is collected by an optical lens, reflected by an optical filter, and emitted into a sleeve connecting an optical fiber,
An optical transmission module comprising: positioning and mounting the optical lens and the optical filter on a single filter lens carrier; and positioning and mounting the laser diode and the filter lens carrier in a ceramic package. Manufacturing method.

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