JP2013171161A - Optical receiving module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized optical receiving module for optical wavelength multiplex communication, capable of decreasing a cost and the number of mounting processes by decreasing the number of components, and reducing superposition of position variation of a plurality of structure components of the optical receiving module.SOLUTION: A package portion of an optical receiving module 10 is mounted with one positioning block 40 on which an optical demultiplexer 31 for demultiplexing wavelength multiplex light incident from a first lens 18 into a plurality of signal light having different wavelength, a reflector 32 for reflecting demultiplexing signal light demultiplexed by the optical demultiplexer 31 toward a package bottom wall direction; a plurality of second lenses 33 for collecting the demultiplexing signal light reflected by the reflector 32 and a plurality of light-receiving elements 34 for respectively receiving the demultiplexing signal light are mounted. On the package portion, a preamplifier circuit 36 can be mounted, too.

Description

  The present invention relates to an optical receiver module used for optical reception such as an optical transceiver.

  In recent years, an increase in the amount of information flowing on a network and an increase in communication speed are progressing. As a result, the speed of optical transmission / reception modules used in optical transceivers and the like mounted on optical transmission equipment has been increased, and currently, transmission speeds of 40 Gbps and 100 Gbps are required. Such a high transmission rate is difficult to follow with a single optical device, and a communication method using wavelength multiplexing is used.

  For example, in Patent Document 1, in order to realize high-speed transmission of 40 Gbps, four sets of optical transmission sub-assemblies (TOSA) operating at a speed of 10 Gbps and an optical multiplexer (MUX) serve as a transmission unit. An optical transceiver is disclosed in which four sets of receiver optical sub-assemblies (ROSA) operating at a speed of 10 Gbps and an optical demultiplexer (De-MUX) are used as receiving units.

In Patent Document 2, a plurality of signal lights having different wavelengths that have been wavelength-multiplexed are separated into respective wavelengths using a wavelength separation unit (light De-MUX), and light wavelengths received by the respective light receiving elements. An optical receiver module for multiplex communication is disclosed.
FIG. 11 is a diagram schematically showing a part of the optical receiver module disclosed in Patent Document 2. In FIG. As shown in FIG. 11A, the wavelength-multiplexed signal light emitted from the optical fiber 1 is collected by the first lens 3 disposed on the substrate 2 and passes through the light reflecting portion 4. The light enters the wavelength separation unit 5.

  The signal light incident on the wavelength separation unit 5 is transmitted through the optical block 5c and reflected by the total reflection surface 5a, and only the signal light having the first wavelength is transmitted by the wavelength filter 5b, and the signal light having other wavelengths is transmitted. Reflect. The first wavelength signal light that has passed through the wavelength filter 5 b is received by the second lens 6 by the predetermined light receiving element 7 a of the light receiving unit 7. The signal light reflected by the wavelength filter 5b is reflected again by the total reflection surface 5a, and only the signal light of the next second wavelength is transmitted by the wavelength filter 5b, and the signal light of other wavelengths is reflected. The signal light having the second wavelength that has passed through the wavelength filter 5b is received by the second lens 6 by the predetermined light receiving element 7a. Hereinafter, similarly, multiplexed signal lights having different wavelengths are separated into signal lights having respective wavelengths and received by the respective light receiving elements 7a of the light receiving unit 7.

  Further, as shown in FIG. 11 (B), after being demultiplexed into a plurality of signal lights having different wavelengths by the wavelength separation unit 5 and condensed by the second lens 6, the direction of the light is changed by the reflection block 8. Thus, it is also disclosed that light is received by the light receiving element 7a. In this case, the light receiving element 7a and the reflection block 8 are mounted on a circuit board 9 different from the board 2 on which the wavelength separation unit 5 is mounted, but these optical components are arranged on the same plane.

JP 2011-118337 A JP 2009-198958 A

  In recent years, while responding to the demand for high-speed transmission of optical communications, there is a strong demand for miniaturization of optical transceivers, and standardization of CFP2, CFP4, QSFP +, etc., which has a smaller outer shape of the industry standard CFP-MSA, has been studied. . In this case, the accommodation area allocated to TOSA or ROSA is reduced. For example, ROSA needs to accommodate the above-described optical components in a package having a width of 7 mm or less. In order to cope with this, in the structure in which a plurality of TOSA and ROSA are arranged as in Patent Document 1, it is difficult to cope with the increase in external dimensions of the package. For this reason, it is necessary to make it the form which integrates and integrates several optical components etc. like patent document 2. FIG.

  In this case, since the output of the light receiving element constituting the ROSA is weak and susceptible to ambient noise, the light receiving element and a preamplifier (amplifier circuit) for amplifying the signal are also incorporated in the same package and arranged at a short distance. It is preferable. However, as shown in FIG. 8, in the structure in which the first lens, the wavelength separation unit, the second lens, the reflection block, and the light receiving element are arranged on the same plane, a sufficient plane area for mounting components can be obtained. Absent. For this reason, in order to mount a preamplifier circuit and to perform wiring by bonding wires, there is a problem that the package must be enlarged and downsizing is difficult.

  Further, since the wavelength separation unit 5 and the second lens 6 are mounted on the substrate 2, and the light receiving element 7 a and the reflection block 8 are mounted on the circuit board 9, the wavelength separation unit 5 and the second lens 2 are mounted on the substrate 2. After positioning and installing the lens 6, the board 2 must be positioned and installed with respect to the circuit board 9, and since there are many parts, variation during positioning is superimposed in the mounting process, and assembly accuracy is increased. There was a problem that it was difficult to improve.

  The present invention has been made in view of the above-described situation, and by reducing the number of components, the cost can be reduced, the mounting process is small, and the overlapping of position variations of a plurality of components of the optical receiver module is reduced. An object of the present invention is to provide a small optical receiver module for optical wavelength division multiplexing communication.

  An optical receiver module according to the present invention includes a receptacle portion to which an optical fiber is connected, a rectangular package portion that houses a light receiving element and an optical component, and a terminal portion that performs electrical connection with an external circuit. This is an optical receiver module that demultiplexes multiplexed light into a plurality of signal lights having different wavelengths, and converts the demultiplexed signal lights into electrical signals.

  A first lens that collimates the light emitted from the optical fiber is disposed on the receptacle of the optical receiver module. The package unit includes an optical demultiplexer for demultiplexing the wavelength multiplexed light incident from the first lens into a plurality of signal lights having different wavelengths, and a demultiplexed signal light demultiplexed by the optical demultiplexer, respectively. Mounted with a reflector that reflects toward the bottom wall, a plurality of second lenses that collect the demultiplexed signal light reflected by the reflector, and a plurality of light receiving elements that respectively receive the demultiplexed signal light One positioning block is mounted.

  The positioning block is integrally formed with a cubic part and a concave part having a concave cross section having a bottom wall part and a side wall part extending in the same direction from the cubic part. A waver is mounted. An alignment marker for mounting the optical demultiplexer is provided on the upper surface of the cube. This alignment marker is formed by a metal vapor deposition film or plating, for example. A reflector is mounted on the upper surface of the side wall of the recess of the positioning block, and a plurality of second lenses and a plurality of light receiving elements are mounted at predetermined intervals inside the recess.

  The plurality of second lenses may have an array shape in which a plurality of lens surfaces are integrally formed, and the plurality of light receiving elements may have an array shape in which a plurality of light receiving elements are integrally formed. In addition, the positioning block may be constituted by a structure in which a plurality of ceramic substrates are stacked, and at that time, a capacitor may be provided together with the electrode pattern on the ceramic substrate on which the plurality of light receiving elements are mounted. Further, a preamplifier circuit for amplifying an output signal from the light reception signal may be housed in the package portion.

  According to the present invention, since the optical demultiplexer, the reflector, the plurality of second lenses, and the plurality of light receiving elements are mounted on one positioning block, the number of components for component mounting is reduced. Can do. For this reason, a mounting process can be reduced and the superimposition of the position variation of each component can be reduced. Furthermore, the plane area can be reduced, and the optical receiver module can be reduced in size.

It is sectional drawing which looked at an example of the optical receiver module by this invention from the upper part. It is sectional drawing which looked at the optical receiver module of FIG. 1 from the side surface. It is a figure for demonstrating an example of the optical demultiplexer used for this invention, and its demultiplexing operation | movement. It is a perspective view which shows an example of the positioning block which mounts the optical demultiplexer, the reflector, the some 2nd lens, and the some light receiving element in the optical receiver module by this invention. It is the figure which looked at the positioning block of FIG. 4 from the upper part. It is a figure for demonstrating the aligning method of the reflector using the positioning block of the optical receiver module by this invention. It is a figure for demonstrating the influence on the optical characteristic by the position of a reflector. It is a figure for demonstrating the alignment method of the optical demultiplexer using the positioning block of the optical receiver module by this invention. It is a perspective view which shows the other example of the positioning block which mounts the optical demultiplexer, the reflector, the some 2nd lens, and the some light receiving element in the optical receiver module by this invention. FIG. 10 is a top view of a case where a preamplifier circuit is connected to the positioning block of FIG. 9. It is a figure for demonstrating a prior art.

  Hereinafter, preferred embodiments of the optical receiver module of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of an example of an optical receiver module according to the present invention as viewed from above, and FIG. 2 is a cross-sectional view of the optical receiver module of FIG.

  In the figure, 10 is an optical receiver module, 11 is a receptacle part, 12 is a package part, 13 is a terminal part, 14 is a sleeve, 15 is a joint sleeve, 16 is a holder, 17 is a stub, 18 is a first lens, and 19 is Optical window, 20 is a package housing, 21 is a package bottom wall, 22 is a package lid, 23 is a bush, 31 is an optical demultiplexer, 32 is a reflector, 33 is a second lens, 34 is a light receiving element, and 35 is A preamplifier circuit 40 is a positioning block.

  The optical receiver module 10 includes a receptacle part 11 to which an optical fiber is connected, a package part 12 in which a light receiving element, an optical component, and the like are accommodated, and a terminal part 13 for electrical connection with an external circuit. The receptacle part 11 includes, for example, a sleeve 14 into which a ferrule of an optical connector (not shown) is inserted, a joint sleeve 15 for coupling in an alignable manner, and a holder 16 that forms a coupling with the package part 12.

The package part 12 is formed in a rectangular box shape. For example, a light receiving element or an optical component, which will be described later, is accommodated in a housing part including a metal package housing 20, a metal package bottom wall 21, and a package lid body 22. It is equipped with. The package bottom wall 21 can be made of a material such as copper molybdenum or copper tungsten, and heat dissipation can be enhanced by using a material having good thermal conductivity. The package lid 22 (see FIG. 2) is fixed in order to keep the package housing 20 in a hermetically sealed state after receiving and wiring the mounted components.
The terminal portion 13 is formed, for example, by laminating a plurality of ceramic substrates and assembled in a form that fits into the rear side of the package housing 20, and an electrode for forming an electrical connection is formed at the exposed end. Has been.

  The holder 16 is fixed to the package part 12 via a bush 23 provided on the front side of the package housing 20. A sleeve 14 is coupled to the holder 16 via a joint sleeve 15, and alignment in the axial direction and the radial direction is performed by the joint sleeve 15. A stub 17 that forms an optical coupling is disposed in the sleeve 14, and a first lens 18 that condenses the signal light emitted from the optical fiber in the stub 17 to be parallel light is disposed on the holder 16. The The signal light from the first lens 18 is emitted into the package portion 12 through an optical window 19 provided in a sealed shape in the bush 23.

  A positioning block 40 is mounted in the package unit 12, and an optical demultiplexer that demultiplexes wavelength multiplexed light emitted from the first lens 18 into a plurality of signal lights having different wavelengths. 31 (also referred to as optical DeMUX) and a reflector 32 formed by a prism or the like that reflects the demultiplexed signal light (hereinafter referred to as demultiplexed signal light) to the package bottom wall side (lower side in FIG. 2). A plurality of second lenses 33 for condensing the demultiplexed signal light reflected by the reflector 32, and a plurality of light receiving elements 34 for receiving the demultiplexed signal light through the second lens 33, respectively. Is installed and implemented.

  Although details of the positioning block 40 will be described later, in the optical receiver module having the above-described configuration, as shown in FIG. 2, the optical demultiplexer 31 and the reflector 32 are parallel to the height direction from the plane of the package bottom wall 21. It is mounted on the mounting surface of the positioning block 40 that is spaced apart from each other. Then, the second lens 33 and the light receiving element 34 are mounted by being arranged in the vertical direction while being spaced apart from the flat surface of the package bottom wall 21 in the height direction using the space of the hollow portion provided in the positioning block 40. The In other words, the reflector 32, the second lens 33, and the light receiving element 34 are arranged so as to overlap in the vertical direction in the package portion, and the arrangement space in the planar direction is reduced.

  As a result, compared with the conventional configuration in which the optical component is mounted on the same plane as shown in FIG. 11B, the plane area for mounting the component of the package portion 12 can be substantially increased. For this reason, it is possible to mount the preamplifier circuit 32 close to the light receiving element 29 without increasing the outer dimension of the package unit 12, and to reduce noise generation. In addition, when mounting the same number of parts as the conventional one, it becomes possible to further downsize the package part.

Here, the optical demultiplexer 31 will be described. FIG. 3 is a diagram showing an example in which an example of the optical demultiplexer 31 and the reflector 32 used in the present invention are integrally assembled on the support substrate 25.
The optical demultiplexer 31 is an example in which a single reflecting member 31a and a plurality of wavelength filters 31b are integrated by a transparent optical member 31c. The reflection member 31a has a reflection surface that reflects light of all wavelengths, and the wavelength filter 31b is formed of an optical element having a different wavelength for each wavelength filter.

  As shown in FIG. 3, the multiplexed signal lights having different wavelengths (λ1, λ2, λ3, λ4) are first applied to the wavelength filter 31b arranged first, and the signal light having the wavelength λ1 is transmitted. However, signal lights (λ2, λ3, λ4) of other wavelengths are reflected. The reflected signal light is applied to the second wavelength filter 31b by the reflecting member 31a, the signal light having the wavelength λ2 is transmitted, and the signal light having other wavelengths (λ3, λ4) is reflected. Thereafter, transmission and reflection are similarly repeated, and the wavelength-multiplexed signal light is demultiplexed into a plurality of signal lights having different wavelengths.

  The reflector 32 is an optical element formed of, for example, a prism, and the reflection surface 32a is mounted at the end of the support substrate so as to face the direction of the optical demultiplexer 31 at an angle of 45 degrees. . Respective signal lights having different wavelengths are reflected by the reflecting surface 32a of the reflector 32 in the orthogonal direction, and are received by the light receiving element through the second lens 33 as described above.

  FIG. 4 is a perspective view illustrating an example of a positioning block in which an optical demultiplexer, a reflector, a plurality of second lenses, and a plurality of light receiving elements are mounted in the optical receiver module according to the present invention. It is the figure which looked at the positioning block of FIG. 4 from the upper part.

  The positioning block 40 is made of a ceramic material such as aluminum oxide (alumina) or an insulating material such as glass, and has a cube-shaped cube portion 40a, and a low wall portion 46 and a side wall extending in the same direction from the cube portion 40a. It has a recessed portion 40 b having a concave section and having a portion 47. An optical demultiplexer 41 and a reflector 32 are mounted on the mounting surface 41 on the upper surface of the cube portion 40a and the mounting surface 42 on the upper surface of the side wall portion 47 of the recess 40b, respectively, on the same plane. On the mounting surface 41 of the optical demultiplexer 31, for example, a triangular alignment marker 51 for positioning the optical demultiplexer 31 is provided. The alignment marker 51 is not limited to a triangular shape, and may be an L-shaped marker having a side 51a or a linear marker indicating the side 51a.

  A mounting surface 43 for mounting the plurality of second lenses 33 is formed in the recess 40b of the positioning block 40, and the plurality of light receiving elements 34 mounted on the mounting surface 44 of the low wall portion 47 of the recess 40b. The plurality of second lenses 33 are mounted in the space 45 of the recess 40b with a predetermined interval. The mounting surface 44 of the light receiving element 34 is provided with an alignment marker 52 for mounting the light receiving element 34.

  Here, the plurality of second lenses 33 may be formed by bonding and fixing a plurality of lenses 33 to a transparent glass substrate at intervals, and the plurality of second lenses 33 are integrated with the glass substrate. A lens array formed in the above may be used. The plurality of light receiving elements 34 may be individually formed and arranged on the mounting surface 44. However, the plurality of light receiving elements 34 are integrally formed to form a light receiving element array. May be used.

  As described above, since the optical demultiplexer 31, the reflector 32, the plurality of second lenses 33, and the plurality of light receiving elements 34 are mounted on one positioning block 40, each of them is coupled with a decrease in the number of parts. Positioning work between mounted parts becomes easy, and the mounting process can be reduced. And the superimposition of the position variation of each component can be reduced. In addition, the positioning block 40 on which the optical element is mounted can be handled as one component, and can be easily assembled in the package part 12, and the workability of assembling the entire optical receiving module can be improved.

  Next, with respect to the alignment method when mounting the optical demultiplexer 31, the reflector 32, the plurality of second lenses 33, and the plurality of light receiving elements 34 on the positioning block 40, a lens array and a light receiving element A case where an array is used will be described. FIG. 6 is a diagram for explaining a reflector alignment method using the positioning block of the optical receiver module according to the present invention.

  First, a light receiving element array having a plurality of light receiving elements 34 is mounted on the mounting surface 44 of the recess 40 b of the alignment block 40. At that time, the alignment marker 52 formed on the mounting surface 44 can be used. Next, a lens array having a plurality of second lenses is mounted on the mounting surface 43. In this case, assuming that the radius of the light receiving surface of each light receiving element 34 is d, the center of each second lens 33 is set. Is positioned so that the mounting position falls within the range of ± d from the center of the light receiving surface of the corresponding light receiving element 34.

  Next, the reflector 32 is mounted on the mounting surface 42 on the upper surface of the side wall 47 of the positioning block 40. At this time, after adjusting by a method such as image recognition so that the end 33a of the lens array of the second lens 33 positioned directly below the reflector and the end 32a of the reflector 32 are parallel, the reflector 32 is adjusted. Is fixed to the mounting surface 42.

  Here, for example, as shown in FIG. 6A, the end 32b of the reflector 32 and the end 33a of the lens array of the second lens 33 are shifted, but as shown in FIG. 6B. In addition, by designing the light λ reflected by the reflector 32 so as to pass through the center of the lens 33 at a position where both ends coincide with each other, for example, the value of the photocurrent flowing through the light receiving element 34 is maximized. It is possible to omit the alignment process of the minute reflector 32.

  FIG. 7 is a diagram for explaining the influence of the position of the reflector on the optical characteristics. As shown in FIG. 7B, when the end 33a of the lens array of the second lens 33 is the reference position X and the end 32b of the reflector 32 is at the reference position X, the second lens 33 If the focal position is set to the center of the light receiving surface of the light receiving element 33, for example, when the reflector 32 is shifted to the right as shown in FIG. 6A, or as shown in FIG. 6C. Even when the reflector 32 is shifted to the left side, the light collection position of the light receiving element 33 does not change.

  As described above, the position where the parallel light reflected by the reflector 32 is collected by the second lens 33 does not depend on the incident position of the parallel light with respect to the lens when the inclination of the lens is ignored. By accurately mounting the lens on the light receiving surface, the influence of the positional deviation of the reflector 32 on the optical characteristics of the light receiving module becomes minor.

FIG. 8 is a diagram for explaining a method of aligning an optical demultiplexer using the positioning block of the optical receiving module according to the present invention.
First, the optical demultiplexer 31 is gripped by an adsorption jig, a jig for mechanically sandwiching, or the like. These jigs include a rotation mechanism for adjusting the side 51a of the alignment marker 51 on the positioning block 40 and the optical demultiplexer 31 in parallel, and the optical demultiplexer 31 separately from the rotation mechanism. A moving mechanism that can move in parallel with the side 51a is provided.

  The jig holding the optical demultiplexer 31 is first moved so that the end of the optical demultiplexer 31 is parallel to the side 51 a of the alignment marker 51 formed on the upper surface of the block 40, and then the position The position of the optical demultiplexer 32 is moved in a direction parallel to the side 51a of the alignment marker 51 (A direction in the figure). At that time, the alignment reference light λ1 is incident from the outside of the package 20, and the reference light λ1 that is passed through the optical demultiplexer 31 and turned back 90 degrees by the reflector 32 is incident on the light receiving element 34. Then, the position of the optical demultiplexer 31 that maximizes the photocurrent value in the light receiving element 34 is determined as the alignment position, and the optical demultiplexer 31 is aligned and fixed to the mounting surface 41 of the positioning block 40.

  Next, another example of the positioning block will be described. FIG. 9 is a perspective view showing another example of a positioning block in which an optical demultiplexer, a reflector, a plurality of second lenses, and a plurality of light receiving elements are mounted in the optical receiver module according to the present invention. These are the figures which looked at the case where a preamplifier circuit is connected to the positioning block of FIG.

  The positioning block 40 ′ has a structure in which a plurality of ceramic substrates are stacked. Similar to the positioning block shown in FIG. 4, the cubic block 40′a and the cubic portion 40′a are arranged in the same direction. It has a recessed section 40′b having a concave cross section having an extended low wall section 46 ′ and a side wall section 47 ′. The optical demultiplexer 31 and the reflector 32 are spaced from each other on the mounting surface 41 ′ on the upper surface of the cube 40 ′ a and the mounting surface 42 ′ on the upper surface of the side wall 47 ′ of the recess 40 ′ b. It is mounted with a gap. On the mounting surface 41 ′ of the optical demultiplexer 31, for example, a triangular alignment marker 51 for positioning the optical demultiplexer 31 is provided.

  A mounting surface 43 ′ for mounting the plurality of second lenses 33 is formed in the recess 40′b of the positioning block 40 ′, and the mounting surface 44 ′ of the low wall portion 46 ′ of the recess 40′b is formed. A plurality of mounted light receiving elements 34 and a plurality of second lenses 33 are mounted at predetermined intervals. Here, the electrode pattern 36 is formed in advance on the ceramic substrate, and the electrode pattern 36 is provided with wiring for transmitting the output from the light receiving element 34 to the preamplifier circuit 35 in the subsequent stage, as shown in FIG. The

  Further, the ceramic substrate may include not only the terminals oriented in the longitudinal direction but also the terminals for the light receiving element 34 oriented sideways. For this reason, the low wall portion 46 ′ has an extending portion 40 ′ C protruding from the positioning block 40 ′ with respect to the arrangement direction of the light receiving elements 33 that is the width direction of the positioning block 40 ′. An electrode pattern 36 is also formed on 'C. The electrode pattern 36 of the extended portion 40'C can be used as an electrode pad for applying a voltage from the external power source to the light receiving element 34, for example. Further, a capacitor 37 for removing high-frequency components that cause noise may be mounted on the mounting surface 44 'in front of the electrode that applies a voltage to each light receiving element 33. Alternatively, the capacitor 37 may be integrated with the ceramic substrate. You may make it form.

DESCRIPTION OF SYMBOLS 10 ... Optical receiver module, 11 ... Receptacle part, 12 ... Package part, 13 ... Terminal part, 14 ... Sleeve, 15 ... Joint sleeve, 16 ... Holder, 17 ... Stub, 18 ... First lens, 19 ... Optical window, DESCRIPTION OF SYMBOLS 20 ... Package housing | casing, 21 ... Package bottom wall, 22 ... Package cover body, 23 ... Bush, 31 ... Optical demultiplexer, 32 ... Reflector, 33 ... 2nd lens, 34 ... Light receiving element, 35 ... Preamplifier circuit, 36 ... Electrode pattern, 37 ... Capacitor, 40 ... Positioning block, 41, 42, 43, 44 ... Mounting surface, 45 ... Space, 46 ... Low wall part, 47 ... Side wall part, 51, 52 ... Positioning marker.

Claims (12)

A receptacle part to which an optical fiber is connected, a rectangular package part for receiving a light receiving element and an optical component, and a terminal part for electrical connection with an external circuit, the received wavelength multiplexed light having a plurality of different wavelengths An optical receiver module that demultiplexes into signal light and converts each demultiplexed signal light into an electrical signal,
The receptacle portion is provided with a first lens that collimates the light emitted from the optical fiber,
The package unit includes an optical demultiplexer for demultiplexing the wavelength multiplexed light incident from the first lens into a plurality of signal lights having different wavelengths, and a demultiplexed signal light demultiplexed by the optical demultiplexer. A reflector that reflects the light toward the bottom wall of the package, a plurality of second lenses that respectively collect the demultiplexed signal light reflected by the reflector, and a plurality that respectively receive the demultiplexed signal light An optical receiving module, wherein one positioning block on which the light receiving element is mounted is mounted.   The positioning block is integrally formed with a cubic part, and a recessed part having a concave cross section having a bottom wall part and a side wall part extending in the same direction from the cubic part. 2. The optical receiving module according to claim 1, wherein an optical demultiplexer is mounted.   The optical receiving module according to claim 2, wherein an alignment marker for mounting the optical demultiplexer is provided on an upper surface of the cube portion of the positioning block.   4. The optical receiver module according to claim 2, wherein the reflector is mounted on an upper surface of a side wall portion of the hollow portion of the positioning block. 5.   5. The device according to claim 2, wherein the plurality of second lenses and the plurality of light receiving elements are mounted at predetermined intervals in a hollow portion of the positioning block. The optical receiver module described.   The optical receiving module according to claim 1, wherein an alignment marker for mounting the light receiving element is provided on the positioning block. The optical receiving module according to claim 1, wherein the plurality of second lenses have an array shape in which a plurality of lens surfaces are integrally formed. The optical receiver module according to claim 1, wherein the plurality of light receiving elements have an array shape in which a plurality of light receiving elements are integrally formed.   The optical receiving module according to claim 1, wherein the positioning block includes a structure in which a plurality of ceramic substrates are stacked.   The optical receiving module according to claim 9, wherein an electrode pattern is formed on a ceramic substrate of the mounting portion of the plurality of light receiving elements of the positioning block. The optical receiver module according to claim 10, wherein a capacitor is provided in the vicinity of the electrode pattern.   The optical receiver module according to claim 1, wherein a preamplifier circuit for amplifying an output signal from the light receiving element is housed in the package unit.

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