JP2004117793A - Optical transmitting and receiving module, its mounting method and optical transmitter-receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmitting and receiving module in which optical coupling of light emitting/receiving elements with an optical fiber can be realized by only adjustment using one condensing lens and in which miniaturization is made easy. <P>SOLUTION: The optical films 103d, 103e of a prism element 103 transmit, in the direction of the upper face 1032 of the prism element, the transmission light entered from the lower face 1031 of the prism element while reflecting, to obliquely the upside of the prism element, the reception light entered from the upper face of the prism element. The optical coupling is performed by one condensing lens 106 installed between the upper face of the prism element and the optical fiber 107. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical transceiver module connected to an optical fiber transmission line for transmitting and receiving an optical signal, a mounting method thereof, and an optical transceiver.
[0002]
[Prior art]
When bidirectional transmission is performed using one optical fiber in an optical transmission system, transmission light emitted from a light emitting element is coupled to an optical fiber, and reception light emitted from the optical fiber is received by a light receiving element. However, various methods have been devised for the method of bonding.
[0003]
What is described in the following Patent Document 1 is one example. This conventional example will be described with reference to FIG. FIG. 17 is described in the above publication and is a view showing a configuration of an optical transmitting and receiving module in a conventional optical signal transmission system. As shown in FIG. 17, a first wavelength λ is placed on the optical axis of the tip surface of the ferrule 41 containing the fiber 42. ₁ Is transmitted in the optical axis direction, and the second wavelength λ ₂ A prism-type wavelength multiplexing / demultiplexing coupler 43 that reflects the received light in the direction perpendicular to the optical axis is fixed, and the light emitting element 22 and the light receiving element 31 are arranged in the optical axis direction and in the direction perpendicular to the optical axis, respectively. A single case member 11 is fixed and supported, and lenses 13 and 33 are arranged on each optical axis between the wavelength multiplexing / demultiplexing coupler 43 and the light emitting element 22 and the light receiving element 31. Transmission light λ from light emitting element 22 ₁ Is transmitted through the wavelength multiplexing / demultiplexing coupler 43 in the optical axis direction as it is to the optical fiber 42, while the received light λ from the optical fiber 42 is ₂ Is reflected by the wavelength multiplexing / demultiplexing coupler 43 in a direction perpendicular to the optical axis and received by the light receiving element 31.
[0004]
[Patent Document 1]
JP 2000-180671 A
[0005]
[Problems to be solved by the invention]
However, in the above-mentioned conventional optical transmitting and receiving module, it is necessary to finely adjust the two lenses 13, 33 and the ferrule 41 in order to accurately perform the optical coupling between the light emitting element 22, the light receiving element 31, and the optical fiber 42. In addition to the large number of adjustment locations, the light-emitting element 22 and the light-receiving element 31 are each mounted on a cylindrical package and fixed in a case, so that it is difficult to reduce the size of the module.
[0006]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. Optical coupling between a light emitting element, a light receiving element, and an optical fiber can be realized only by adjustment (alignment) using a single condenser lens, and miniaturization can be achieved. An object of the present invention is to provide an easy optical transmitting / receiving module, a mounting method thereof, and an optical transmitting / receiving device.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 achieves the above object,
A prism element having at least two light-transmissive substrates bonded thereto and having parallel upper and lower surfaces;
Arranged at an interface between the two substrates, transmitting light incident from the lower surface of the prism element in the direction of the upper surface of the prism element, and receiving light incident from the upper surface of the prism element obliquely above the prism element. An optical film that reflects light to
It has an upper surface parallel to the lower surface of the prism element and a surface perpendicular to the upper surface, and the lower surface of the prism element is fixed to the upper surface, or the lower surface parallel to the upper surface is fixed on the main substrate or A radiating substrate integrally formed with the main substrate, and a light emitting element attached to a vertical surface of the radiating substrate and emitting transmission light toward a lower surface of the prism element;
A light receiving element attached to receive the received light reflected obliquely above the prism element on the upper surface of the prism element,
A condenser lens provided between the upper surface of the prism element and the optical fiber,
Configuration.
With the above-described configuration, the heat dissipation substrate on which the light emitting element is mounted, and the prism element having the optical film, on which the light receiving element is mounted, each having a simple shape, can be miniaturized by sequentially integrating and mounting on the main substrate. In addition, the optical coupling between the light emitting element, the light receiving element and the optical fiber can be realized only by adjustment (alignment) using one condensing lens. In addition, on the optical fiber side surface of the prism element, that is, on the upper surface, the position of the light receiving element with respect to the center point of the optical film is uniquely determined, and passive alignment of the light receiving element becomes possible.
[0008]
According to a second aspect of the present invention, in the optical transceiver module according to the first aspect,
The optical film transmits transmission light emitted from the light emitting element at a certain rate, and receives light emitted from the optical fiber and collected by the condenser lens at a certain rate. It is a half mirror that reflects light to the light receiving element side.
With the above configuration, the present invention can be applied to a transmission / reception module for time multiplex communication having the same wavelength.
[0009]
According to a third aspect of the present invention, in the optical transceiver module according to the first aspect,
The optical film transmits the transmission light of the first wavelength emitted from the light-emitting element completely, and the second wavelength is different from the first wavelength emitted from the optical fiber and collected by the condenser lens. It is a wavelength filter that totally reflects received light of a wavelength.
According to the above configuration, the present invention can be applied to a transmission / reception module for wavelength division multiplexing communication in which a transmission wavelength and a reception wavelength are different, and by using a wavelength filter, loss of light emitted from a light emitting element and light incident to a light receiving element can be reduced.
[0010]
According to a fourth aspect of the present invention, in the optical transceiver module according to the third aspect,
The light receiving element is characterized in that the light receiving sensitivity of the receiving wavelength as the second wavelength has a sufficiently large light receiving sensitivity wavelength dependency with respect to the light receiving sensitivity of the transmitting wavelength as the first wavelength.
According to the above configuration, it is possible to improve optical crosstalk caused by a part of the transmission light entering the light receiving element.
[0011]
According to a fifth aspect of the present invention, in the optical transmission / reception module according to any one of the first to fourth aspects,
The light emitting element is mounted on a heat radiating substrate such that an emission direction of transmission light is slightly inclined with respect to an optical axis of an optical fiber.
According to the above configuration, it is possible to suppress multiple reflection of light emitted from the light emitting element and received light from the optical fiber between the both end faces of the prism element and both end faces of the light emitting element.
[0012]
According to a sixth aspect of the present invention, in the optical transceiver module according to any one of the first to fifth aspects,
An anti-reflection film is coated on the outer wall surface of the prism element at a position where transmission and reception light is transmitted.
With the above configuration, reflection of transmission / reception light and the like can be suppressed.
[0013]
According to a seventh aspect of the present invention, in the optical transceiver module according to any one of the first to sixth aspects,
A light-shielding film is provided on an upper surface which is a surface opposite to a light-receiving surface of the light-receiving element.
With the above configuration, waveform deterioration due to a part of the received light directly entering the light receiving element without passing through the optical film, and optical crosstalk due to stray light of the transmitted light entering from the optical fiber side of the light receiving element. Can be reduced.
[0014]
According to an eighth aspect of the present invention, in the optical transceiver module according to any one of the first to seventh aspects,
An output monitoring light-receiving element is mounted at a position on the main substrate at which the rear emission light of the light-emitting element can be received.
With the above configuration, further integration including the output monitoring light receiving element is possible.
[0015]
According to a ninth aspect of the present invention, in the optical transceiver module according to any one of the first to seventh aspects,
An output monitoring light receiving element is mounted on a side surface of the prism element capable of receiving the light reflected by the optical film on the transmission light emitted from the light emitting element.
According to the above configuration, in the transmission / reception module for time multiplex communication or the transmission / reception module for wavelength multiplex communication, the distance from the main substrate to the upper surface of the prism element can be reduced, and the size can be further reduced.
[0016]
According to a tenth aspect of the present invention, in the optical transceiver module according to any one of the second to fifth aspects,
The light receiving element receives both the reception light and the transmission light, and also serves as an output monitoring light reception element of the light emitting element.
With the above configuration, in time-multiplexed bidirectional communication, the light receiving element functions as an output monitor during transmission and functions as a reception during reception, so that the number of components can be reduced, and the configuration can be simplified and cost can be reduced. it can.
[0017]
According to an eleventh aspect of the present invention, in the optical transceiver module according to any one of the first to tenth aspects,
The light emitting element is configured to emit transmission light in a direction perpendicular to a mounting surface, and is mounted on the main substrate instead of the vertical surface of the heat dissipation substrate.
According to the above configuration, since the angular accuracy of the side surface of the heat radiating substrate does not affect the emission direction of the light emitting element, the angular accuracy of the side surface of the heat radiating substrate can be reduced, and the distance from the main substrate to the upper surface of the prism element can be shortened. , More compact.
[0018]
According to a twelfth aspect of the present invention, in the optical transceiver module according to any one of the first to tenth aspects,
A preamplifier is mounted near the light receiving element on the upper surface of the prism element, and an output current of the light receiving element is amplified and output.
According to the above configuration, further integration including a preamplifier can be performed, and electric crosstalk between transmission and reception signals during high-speed modulation can be reduced.
[0019]
According to a thirteenth aspect, in the optical transceiver module according to the twelfth aspect,
The upper surface side of the heat dissipation substrate is formed so that the side surface and the lower surface of the prism element can be fitted together, and the upper surface of the heat dissipation substrate and the upper surface of the prism element are substantially flush with each other. It is characterized in that it is mounted on the upper surface of the heat dissipation substrate instead of the upper surface of the element.
According to the above configuration, since the prism element is fixed on two surfaces, the mounting process such as the position adjustment of the prism element can be simplified, and the heat radiation of the preamplifier can be improved because the preamplifier is mounted on the heat dissipation board.
[0020]
According to a fourteenth aspect of the present invention, in the optical transceiver module according to any one of the first to thirteenth aspects,
The optical film, instead of reflecting the transmission light incident from the upper surface of the prism element obliquely upward of the prism element, and arranged to reflect in a substantially horizontal direction, and the light receiving element of the upper surface of the prism element Instead, the prism element is arranged on the side surface in the same direction as the light emitting element.
According to the above configuration, since the mounting surfaces of the light emitting element and the light receiving element are in the same direction, the mounting process can be simplified.
[0021]
According to a fifteenth aspect of the present invention, in the optical transceiver module according to the fourteenth aspect,
The angle of the optical film with respect to the main substrate is an acute angle shifted from 135 degrees.
With the above configuration, it is possible to suppress the reception light emitted from the optical fiber from being reflected by the end face of the light receiving element and returning to the optical fiber side.
[0022]
The invention according to claim 16 is the optical transceiver module according to claim 14 or 15,
The optical film is configured to reflect a part of the transmission light incident from the lower surface of the prism element in a direction opposite to the light receiving element, and on a side surface of the prism element opposite to the light receiving element mounting surface. A light receiving element for output monitoring is mounted. With the above configuration, further integration including the output monitoring light receiving element can be performed without changing the distance from the main substrate to the upper surface of the prism element, that is, the external dimensions of the entire module.
[0023]
The invention according to claim 17 is the optical transmission / reception module according to any one of claims 14 to 16, wherein
The upper surface side of the heat radiating substrate is formed so that the side surface and the lower surface of the prism element can be fitted together, and the side surface of the heat radiating substrate and the side surface of the prism element are substantially the same, and the light receiving element, A preamplifier is mounted on each of the side surfaces of the prism element and the heat dissipation board.
According to the above configuration, since the mounting surfaces of the light emitting element, the light receiving element, and the preamplifier are in the same direction, the mounting process can be simplified.
[0024]
The invention according to claim 18 is the optical transceiver module according to any one of claims 1 to 17,
The condensing lens is integrally formed on the upper surface of the prism element, and optically coupled directly from the prism element to the optical fiber.
With the above configuration, the prism element can also have the function of a condenser lens, and the configuration can be simplified.
[0025]
According to a nineteenth aspect of the present invention, in the optical transceiver module according to any one of the first to seventeenth aspects,
The heat dissipation substrate and the prism element mounted on the main substrate are hermetically sealed by covering with a cap, and the condenser lens is provided in an opening window on the optical fiber side of the cap.
According to the above configuration, the cap for sealing can also have the function of the fixture for the condenser lens, and the configuration can be simplified.
[0026]
According to a twentieth aspect of the present invention, there is provided a method for mounting the optical transceiver module according to any one of the first to nineteenth aspects,
The light-emitting element is mounted on the heat-dissipating substrate located on the main substrate, and the light-receiving element is mounted in alignment with a center point of the optical film on the prism element, and the light-emitting element and Electrical connection of the light receiving element to enable power supply,
Next, the prism element is mounted on the heat dissipation substrate with the emission point of the light emitting element and the center point of the optical film being aligned with each other,
Next, the light emitting element emits light, and the condenser lens is fixed to the main substrate so that coupling with the condenser lens is maximized,
Finally, the position of the optical fiber is finely adjusted so that the coupling efficiency of the light emitted from the light emitting element to the optical fiber is maximized, and the optical fiber is fixed to the main substrate.
According to the above method, the coupling of the light emitting element and the light receiving element to the optical fiber can be realized by only one condensing lens and optical adjustment of the optical fiber.
[0027]
According to a twenty-first aspect of the present invention, there is provided an optical transceiver including one or more optical transceiver modules according to any one of the first to eighteenth aspects.
With the above configuration, the size of the optical transceiver can be reduced, and a multi-port optical transceiver having integrated optical transceiver modules can be realized.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
<First embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. FIG. FIG. 1 is a diagram of the optical transceiver module of the present invention viewed from the side, and FIG. 2 is a diagram of FIG. 1 viewed from the right side (the optical fiber 107 is not shown). 1 and 2, a main substrate 101 is a substrate having high thermal conductivity, and has pins 101a on its lower surface for electrical connection to the outside.
[0029]
On the upper surface (surface on the optical fiber 107 side) 101b of the main substrate 101, a heat radiation substrate 102 is mounted or integrated with the main substrate 101, and a reference surface (the optical fiber 107 side) which is the upper surface of the heat radiation substrate 102 is provided. The prism element 103 is mounted on the surface 102a. The heat radiating substrate 102 is made of a material having high thermal conductivity and a small coefficient of thermal expansion. ₂ It has a structure in which a dielectric multilayer film is deposited on two substrates (described later with reference to FIG. 3) having optical transparency.
[0030]
Each of the heat dissipation substrate 102 and the prism element 103 has a shape such as a rectangular parallelepiped having a surface perpendicular to the upper surface 101b of the main substrate 101, and upper and lower surfaces parallel thereto. A light emitting element 104 is mounted on a surface 102b of the heat radiation substrate 102 which is perpendicular to the main substrate 101 such that an emission direction faces a direction of the prism element 103 (a direction toward the optical fiber 107). The light receiving element 105 is mounted on the upper surface 1032 (the surface on the side of the optical fiber 107) of the prism element 103 such that the light receiving surface faces down. Further, the electrodes of the light emitting element 104 and the light receiving element 105 are electrically connected directly or indirectly to the output pins 101a of the main substrate 101 (not shown).
[0031]
Here, with respect to the emission direction of the light emitting element 104, if the light emitting element 104 is mounted so as to be inclined by several degrees with respect to the vertical line of the lower surface 1031 of the prism element 103 as shown in FIG. Multiple reflection of the received light between the lower surface 1031 and the upper surface 1032 of the prism element 103 and the emission surface of the light emitting element 104 can be suppressed.
[0032]
FIG. 3 is an exploded perspective view showing two substrates (a first substrate 103b and a second substrate 103c) of the prism element 103. As shown in FIG. 3, the prism element 103 has a structure in which a first substrate 103b and a second substrate 103c are joined, and a right surface of the first substrate 103b in FIG. And the angle θ of the left surface of the second substrate 103c with respect to the reference surface 103a. ₁ Has a predetermined acute angle of 45 degrees or less, and has a half mirror 103d at the interface between the first substrate 103b and the second substrate 103c. Therefore, the half mirror 103 d reflects the received light incident from the upper optical fiber 107 via the upper surface 1032 of the prism element 103 obliquely above the prism element 103. The optical film denoted by reference numeral 103e will be described in a second embodiment.
[0033]
In addition, a light-shielding film (not shown) is provided on the surface of the light receiving element 105 on the side of the optical fiber 107 (the surface opposite to the light receiving surface), so that a part of the received light is converted into an optical film (half mirror 103d). The optical crosstalk and other noise caused by directly entering the light receiving element 105 without passing through the optical fiber and stray light of the transmission light entering from the optical fiber side surface of the light receiving element 105 can be reduced. Furthermore, by making the light receiving element 105 have a sufficiently large light receiving sensitivity wavelength dependency of the light receiving sensitivity at the receiving wavelength with respect to the light receiving sensitivity at the transmitting wavelength, optical crosstalk due to receiving stray light of the transmitting light is reduced. Can be done. Further, for the purpose of suppressing the reflection of the transmitted / received light, an antireflection film (not shown) is coated on the outer wall of the prism element 103 at a position where the transmitted / received light is transmitted.
[0034]
Next, a description will be given of a procedure for mounting the optical transceiver module having the above configuration. The light emitting element 104 is mounted on the vertical surface 102b which is the side surface of the heat radiation substrate 102 mounted on or integrated with the main substrate 101, and the light receiving element 105 is mounted on the upper surface 1032 of the prism element 103 with respect to the center point of the half mirror 103d. After that, the light emitting / receiving element and the heat radiation substrate 102 and the prism element 103 or the main substrate 101 are electrically connected to each other so that power can be supplied.
[0035]
Next, after mounting the prism element 103 on the reference surface 102a of the heat dissipation substrate 102 so that the emission point of the light emitting element 104 and the center point of the half mirror 103d of the prism element 103 are aligned, the light emitting element 104 emits light and the condensing lens The condenser lens 106 is fixed to the main substrate 101 so that the coupling with the optical fiber 107 is maximized, and finally the optical fiber 107 is coupled with the optical fiber 107 so that the coupling efficiency of the light emitted from the light emitting element 104 to the optical fiber 107 is maximized. The position is finely adjusted and fixed to the main board 101.
[0036]
Here, since the light receiving element 105 is mounted in advance with accurate positioning with respect to the center point of the half mirror 103d, optical coupling between the light receiving element 105 and the optical fiber 107 can be realized at the same time. The mounting method described above can be realized in a similar manner in all of the following embodiments.
[0037]
Next, the operation of the optical transceiver module will be described. First, light emitted from the light emitting element 104 passes through the half mirror 103d of the prism element 103 toward the optical fiber 107 at a certain ratio, and the remaining light is reflected. The transmitted light is collected by the condenser lens 106, coupled to the optical fiber 107, and transmitted. On the other hand, the received light transmitted via the optical fiber 107 is condensed by the condenser lens 106 and is reflected at a certain rate by the half mirror 103d of the prism element 103, and the remaining light is directed to the light emitting element 104 side. To Penetrate. The received light reflected by the half mirror 103d enters the light receiving element 105. Note that the transmission signal and the reception signal in the present embodiment are burst signals, and are transmitted by being divided by time (time division multiplexing).
[0038]
As described above, the light emitting element 104 for transmission is mounted on the vertical surface 102b of the heat radiation substrate 102 which is perpendicular to the main substrate 101, and the light receiving element 105 for reception is mounted on the upper surface 1032 of the prism element 103 having the half mirror 103d. The prism element 103 is mounted so as to be aligned with the center point of the half mirror 103 d with high positional accuracy, and the center point of the half mirror 103 d of the prism element 103 and the emission point of the light emitting element 104 are collated. By mounting it on the optical transmission / reception module, it is possible to integrate and reduce the size of the optical transmission / reception module. And the optical fiber 107 can be realized at the same time, and the mounting can be simplified.
[0039]
<Second embodiment>
Hereinafter, a second embodiment of the present invention will be described with reference to FIG. The main configuration is the same as that of the first embodiment, but a wavelength filter 103e is inserted instead of the mounting position of the half mirror 103d of the prism element 103 in the first embodiment. Also, the transmission wavelength at which the light emitting element 104 oscillates is different from the reception wavelength at which the light receiving element 105 receives light, and the wavelength filter 103e has a characteristic that the transmission wavelength is completely transmitted and the reception wavelength is totally reflected.
[0040]
The operation of the present embodiment will be described below. First, the light emitted from the light emitting element 104 passes through the wavelength filter 103e to the optical fiber 107 side. The transmitted light is collected by the condenser lens 106, coupled to the optical fiber 107, and transmitted. On the other hand, the received light transmitted via the optical fiber 107 is condensed by the condenser lens 106, totally reflected by the wavelength filter 103 e, and enters the light receiving element 105. As described above, by using the wavelength filter 103e instead of the half mirror 103d and setting the transmission wavelength and the reception wavelength to be different from each other, it is possible to reduce the loss of the outgoing light of the light emitting element 104 and the incident light of the light receiving element 105. The present invention can be applied to a duplex wavelength multiplexing communication transmitting / receiving module.
[0041]
<Third embodiment>
Hereinafter, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 shows the configuration of the optical transceiver module according to the third embodiment. The main configuration is the same as in the first and second embodiments, except that the output monitoring light-receiving element 108 is mounted on the upper surface 101b of the main substrate 101 at a position where a part of the light emitted backward from the light-emitting element 104 can be received. are doing. Regarding the operation of the present embodiment, the transmission and reception are the same as those of the first and second embodiments, so the description is omitted here, and the output control operation of the light emitting element 104 by the output monitoring light receiving element 108 will be described next. Will be described.
[0042]
The light emitting element 104 also emits light backward with respect to the transmission light emission direction. The output current of the light receiving element 108 which has received a part of the backward emission light is monitored, and such that the output current becomes constant. By controlling the bias current of the light emitting element 104, control is performed to keep the output light level constant. As described above, by mounting the output monitoring light-receiving element 108 at the position on the main substrate 101 where the backward emission light of the transmission light-emitting element 104 can be received, the optical transmission / reception module can be further integrated and the mounting is simplified. Can be
[0043]
<Fourth embodiment>
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 shows the configuration of the optical transceiver module according to the fourth embodiment. The main configuration is the same as that of the first embodiment. However, in the first embodiment, the output monitor is provided on the vertical side surface of the prism element 103 in the same direction as the mounting surface of the light emitting element 104 of the heat radiation substrate 102. The light receiving element 108 is mounted. The optical film denoted by reference numeral 103f will be described in a fifth embodiment.
[0044]
The operation of this embodiment is almost the same as the first and third embodiments, except for the light receiving path of the light emitted from the light emitting element 104 to the output monitoring light receiving element 108. A part of the light emitted from the light emitting element 104 and reflected by the half mirror 103d enters the output monitoring light receiving element 108. As described above, by mounting the output monitoring light receiving element 108 on the side surface of the prism element 103 in the same direction as the vertical surface 102b on which the light emitting element 104 is mounted on the heat radiation substrate 102, the transmission / reception module for time multiplex communication can be realized. In addition, the distance from the upper surface 101b of the main substrate 101 to the upper surface 1032 of the prism element 103 can be reduced, and the size can be further reduced.
[0045]
<Fifth embodiment>
Hereinafter, a fifth embodiment of the present invention will be described with reference to FIGS. 5 and 6, similarly to the fourth embodiment. The main configuration is the same as that of the fourth embodiment, except that a wavelength filter 103f is mounted instead of the mounting position of the half mirror 103d of the prism element 103 in the fourth embodiment. Here, the wavelength characteristic of the wavelength filter 103f is shown in FIG. 6, and has a characteristic that the light is totally reflected at the reception wavelength, transmitted at a certain rate at the transmission wavelength, and reflects the remaining light.
[0046]
The operation of the present embodiment is the same as that of the fifth embodiment. The light received from the optical fiber 107 is totally reflected by the wavelength filter 103f and enters the light receiving element 105, while the light emitted from the light emitting element 104 is emitted. Is transmitted through the second wavelength filter 103f at a certain rate, the rest is reflected, and a part of the reflected light is received by the output monitoring light receiving element 108. As described above, the transmittance of the wavelength filter 103f that transmits the light emitted from the light emitting element 104 to the optical fiber 107 side is partially reflected as a certain value, and a part of the reflected light is In the wavelength multiplexing communication transmitting / receiving module, the light is received by the output monitoring light receiving element 108 mounted on the prism element in the same direction as the mounting surface of the light emitting element, as in the fourth embodiment. The distance from 101b to the upper surface 1032 of the prism element 103 can be reduced, and the size can be further reduced.
[0047]
<Sixth Embodiment>
Hereinafter, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 7 shows the configuration of the optical transceiver module according to the sixth embodiment. The main configuration is the same as in the first and second embodiments, except that a part of the transmission light transmitted through the optical film 103d (or 103e) and the reception light reflected from the optical film 103d (or 103e). The light receiving element 105 is mounted at a position where both can receive light, and the operation of the light receiving element 105 functions as an output monitoring light receiving element during transmission and functions as a reception light receiving element during reception. Other operations are the same as those of the first, third, and fourth embodiments.
[0048]
As described above, by mounting the light receiving element 105 at a position on the prism element 103 at which a part of the received light and the transmitted light can be received, one light receiving element 105 can function as an output monitor and a receiver. Thus, the number of components can be reduced.
[0049]
<Seventh embodiment>
Hereinafter, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 8 shows the configuration of the optical transceiver module according to the seventh embodiment. The main configuration is the same as in the first to sixth embodiments, except that the light emitting element 109 is a surface light emitting element and the surface light emitting element 109 is mounted on the upper surface 101b of the main substrate 101.
[0050]
The operation of this embodiment is the same as that of the first to sixth embodiments, and the surface emitting element 109 emits the emitted light to the prism element 103 side, which is the upper direction of the element, and outputs the half mirror 103d or the wavelength filter 103e. Alternatively, the light passes through 103f, is condensed by the condenser lens 106, and is coupled to the optical fiber 107.
[0051]
As described above, by mounting the surface light emitting element 109 on the upper surface 101b of the main substrate 101 as the light emitting element, the angular accuracy of the vertical surface 102b of the heat radiation substrate 102 does not affect the emission direction of the light emitting element 109. The angle accuracy of the vertical surface 102b of the substrate 102 can be reduced, and the distance from the main substrate 101 to the upper surface 1032 of the prism element 103 can be shortened, so that the size can be further reduced.
[0052]
<Eighth Embodiment>
Hereinafter, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 9 shows the configuration of the optical transceiver module according to the eighth embodiment. The main configuration is the same as that of the first or second embodiment except that a preamplifier 110 is mounted near the light receiving element 105 on the upper surface 1032 of the prism element 103, and the input terminals of the light receiving element 105 and the preamplifier 110, the preamplifier 110 And the output pins 101a of the main board 101 are electrically connected (not shown).
[0053]
The operation of this embodiment is almost the same as that of the first or second embodiment, except that the output current of the light receiving element 105 is amplified by the preamplifier 110 and output to the output pin 101a of the main board 101. It was done. As described above, by mounting the preamplifier 110 near the light receiving element 105, electric crosstalk can be reduced.
[0054]
<Ninth embodiment>
Hereinafter, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 10 shows the configuration of the optical transceiver module according to the ninth embodiment. The main configuration is the same as that of the first or second embodiment, except that the shape of the heat dissipation board 111 is different, and the heat dissipation board 111 is located on the upper surface of the heat dissipation board 111 on the optical fiber 107 side at a position away from the mounting surface of the light emitting element 104. It has a stepped shape provided with a rectangular projection 111a. The height of the projection 111a is substantially the same as the height of the prism element 103. The prism element 103 is formed by the upper surface 1111 of the lower step formed by the projection 111a of the heat radiation substrate 111 and the side surface 1112 of the projection 111a. Fixed to. In addition, the preamplifier 110 is mounted on the upper surface 1113 of the upper stage formed by the protrusion 111a.
[0055]
The operation of the present embodiment is the same as that of the eighth embodiment, and will not be described here. As described above, since the prism element 103 is fixed on the two surfaces of the flat surface 1111 of the heat dissipation substrate 102 other than the projection 111a on the optical fiber 107 side and the side surface 1112 of the rectangular parallelepiped projection 111a, the position adjustment of the prism element 103 is performed. In addition, the mounting process such as the above can be simplified, and since the preamplifier 110 is mounted on the heat dissipation board 102, the heat dissipation of the preamplifier 110 can be improved.
[0056]
<Tenth embodiment>
Hereinafter, a tenth embodiment of the present invention will be described with reference to FIG. FIG. 11 shows the configuration of the optical transceiver module according to the tenth embodiment. The main configuration is the same as that of the first or second embodiment, but the reflection angle of the optical film 112a in the prism element 112 is different by about 180 degrees. That is, the angle θ of the optical film 112a with respect to the main substrate 101 ₂ Is different from the optical film in the first and second embodiments in that the optical film is an acute angle of 45 degrees or less, but is obtuse, and the light receiving element 105 is the same as the mounting surface of the heat radiation substrate 102 on which the light emitting element 104 is mounted. It is configured to be mounted on the side surface of the prism element 112 in the orientation.
[0057]
Note that the angle θ of the optical film 112a with respect to the main substrate is ₂ By making the angle shifted by about 10 degrees with respect to 135 degrees, it is possible to suppress the reflected light of the reception light emitted from the optical fiber 107 at the end face of the light receiving element from returning to the optical fiber 107 side.
[0058]
The operation of the present embodiment is almost the same as that of the first and second embodiments, except that only the incident path of the received light to the light receiving element 105 is different. The reception light emitted from the optical fiber 107 is condensed by the condenser lens 106, reflected by the optical film 112 a toward the light receiving element 105, that is, in the right-hand direction as viewed in the drawing, and received by the light receiving element 105. As described above, the angle of the prism element 112 with respect to the main substrate 101 is set to a predetermined obtuse angle, and the light-receiving element 105 is mounted on the side of the prism element in the same direction as the mounting surface of the light-emitting element of the heat radiation substrate 102, so that the light-emitting element 104 Since the mounting surfaces of the light receiving elements 105 are in the same direction, the mounting process can be simplified.
[0059]
<Eleventh embodiment>
Hereinafter, an eleventh embodiment of the present invention will be described with reference to FIG. FIG. 12 shows the configuration of the optical transceiver module according to the eleventh embodiment. The main configuration is the same as that of the tenth embodiment. In the tenth embodiment, the output monitoring light receiving element 108 is mounted on the side surface of the prism element 112 opposite to the mounting surface of the light receiving element 105. . The operation of this embodiment is almost the same as that of the tenth embodiment except that the output of the light emitted from the light emitting element 104 is reflected by the optical film 112a in the direction opposite to the mounting direction of the light receiving element 105. The monitor light receiving element 108 receives a part of the light. The optical film 112a is the half mirror 103d described above or the wavelength filter 103f having the characteristics shown in FIG.
[0060]
As described above, by mounting the output monitoring light receiving element 108 on the side surface of the prism element 112 opposite to the mounting surface of the light receiving element 105, the distance from the main substrate 101 to the upper surface of the prism element 112, that is, the outer shape of the entire module Without changing the dimensions, further integration including the output monitoring light receiving element 108 can be performed.
[0061]
<Twelfth embodiment>
Hereinafter, a twelfth embodiment of the present invention will be described with reference to FIG. FIG. 13 is a diagram of the optical transceiver module according to the twelfth embodiment viewed from the mounting surface side of the light emitting element 104 and the light receiving element 105. The main configuration is the same as that of the ninth embodiment shown in FIG. 10, but the shape of the heat radiation substrate 113 is different, and the vertical shape of the light receiving element 105 of the prism element 112 is provided on the upper surface of the heat radiation substrate 113 on the optical fiber 107 side. A rectangular parallelepiped projection 113a is provided along the adjacent surface 112b which is a side surface perpendicular to the horizontal direction with respect to the mounting surface.
[0062]
The height of the projection 113a is substantially the same as the height of the prism element 112, and the prism element 112 is fixed by the upper surface 1131 of the lower step formed by the projection 113a of the heat radiation substrate 113 and the side surface 1132 of the projection 113a. Have been. Further, in the prism element 112, the preamplifier 110 is mounted on the same surface as the mounting surface of the light emitting element 104, which is the side surface of the projection 113a, and as close as possible to the light receiving element 105.
[0063]
The operation of the present embodiment is the same as that of the eighth embodiment, and will not be described here. As described above, the heat radiating substrate 113 has a shape including the rectangular parallelepiped protrusion 113a provided along the side surface of the prism element 112, and the prism element 112 is mounted on the side surface of the protrusion 113a and on the same surface as the mounting surface of the light emitting element. By doing so, the mounting surfaces of the light emitting element 104, the light receiving element 105, and the preamplifier 110 are in the same direction, and the mounting process can be simplified.
[0064]
<Thirteenth embodiment>
Hereinafter, a thirteenth embodiment of the present invention will be described with reference to FIG. FIG. 14 shows the configuration of the optical transceiver module according to the thirteenth embodiment. The shapes and mounting positions of the heat radiation substrates 102, 111, 113, the prism elements 103, 112, and the mounting positions of the light emitting element 104, the light receiving element 105, the output monitoring light receiving element 108, the surface light emitting element 109, and the preamplifier 110 are the first to twelfth. Which is one of the embodiments. FIG. 14 shows the configuration of the tenth embodiment.
[0065]
The difference from the first to twelfth embodiments is that a lens portion 112c is integrally formed on the upper surface 1032 on the optical fiber 107 side in the prism element 112 according to the tenth embodiment. That is, there is no need to separately provide the condenser lens 106, and the prism element 112 has a function also serving as the condenser lens 106. As described above, by integrally forming the lens portion 112c on the upper surface 1032 of the prism element 112 on the optical fiber 107 side, the number of components can be reduced.
[0066]
<Fourteenth embodiment>
Hereinafter, a fourteenth embodiment of the present invention will be described with reference to FIG. FIG. 15 shows the configuration of the optical transceiver module according to the fourteenth embodiment. The shapes and mounting positions of the heat radiation substrates 102, 111, 113, the prism elements 103, 112, and the mounting positions of the light emitting element 104, the light receiving element 105, the output monitoring light receiving elements 108, 109, and the preamplifier 110 are the same as those of the first to twelfth embodiments. One of the forms. FIG. 15 shows a configuration in the case of the tenth embodiment.
[0067]
A method for fixing the condenser lens 106 according to the tenth embodiment will be described below. In FIG. 15, the main board 101 on which all the components are mounted is hermetically sealed by a sealing cap 114 in order to enhance the moisture resistance. However, the sealing between the prism element 112 and the optical fiber 107 is performed. The condenser lens 106 is set in the opening window of the stop cap 114. However, the height of the cap needs to be determined in advance so that the position of the condenser lens 106 is the same as in each embodiment. As described above, by installing the condenser lens 106 in the opening window located between the prism element 112 and the optical fiber 107 of the sealing cap 114 mounted on the main substrate 101, sealing for maintaining airtightness is achieved. The cap 114 can also function as a holder for the condenser lens 106, and the configuration can be simplified.
[0068]
<Fifteenth embodiment>
Hereinafter, a fifteenth embodiment of the present invention will be described with reference to FIG. FIG. 16 shows the configuration of the optical transceiver of the present invention. The configuration inside the optical transceiver module 115 is any of the first to fourteenth embodiments. FIG. 16 shows the configuration in the case of the fourteenth embodiment. One or a plurality of optical transmission / reception modules 115 are mounted on a main resin substrate 116 of the optical transmission device, and are housed in an optical transmission / reception device housing 117. An optical fiber connector plug 118 having an optical input / output port function is attached to a front panel of the housing 117. As described above, by housing the optical transceiver module including the main board, the heat radiation board, and the prism element in the optical transceiver apparatus housing, the optical transceiver apparatus can be downsized. A port optical transmission / reception device can be realized.
[0069]
【The invention's effect】
According to the first aspect of the present invention, as described above, the main substrate includes a heat dissipation substrate on which a light emitting element is mounted and a prism element having an optical film on which a light receiving element is mounted, each having a simple shape. The size can be reduced by being integrated and mounted in the above order, and the optical coupling between the light emitting element, the light receiving element and the optical fiber can be realized only by adjustment (alignment) using one condensing lens. In addition, on the upper surface of the prism element on the optical fiber side, the position of the light receiving element with respect to the center point of the optical film is uniquely determined, and passive alignment of the light receiving element becomes possible.
According to the second aspect of the present invention, the present invention can be applied to a transmission / reception module for time multiplex communication of the same wavelength.
According to the third aspect of the present invention, the present invention can be applied to a transmission / reception module for wavelength division multiplexing communication in which a transmission wavelength and a reception wavelength are different from each other. Can be reduced.
According to the fourth aspect of the invention, it is possible to improve optical crosstalk caused by a part of the transmission light entering the light receiving element.
According to the fifth aspect of the invention, it is possible to suppress multiple reflections of light emitted from the light emitting element and received light from the optical fiber between both end faces of the prism element and both end faces of the light emitting element.
According to the invention described in claim 6, reflection of transmission / reception light and the like can be suppressed.
According to the invention as set forth in claim 7, deterioration of the waveform due to part of the received light directly entering the light receiving element without passing through the optical film, and stray light of the transmitted light from the optical fiber side surface of the light receiving element Optical crosstalk due to incidence can be reduced.
According to the eighth aspect of the present invention, further integration including the output monitoring light receiving element is possible.
According to the ninth aspect of the present invention, in the transmission / reception module for time multiplex communication or the transmission / reception module for wavelength multiplex communication, the distance from the main substrate to the upper surface of the prism element can be reduced, and the size can be further reduced.
According to the tenth aspect of the present invention, in time multiplex bidirectional communication, the light receiving element functions as an output monitor during transmission and functions as a reception during reception, so that the number of components can be reduced and the configuration can be simplified. And cost can be reduced.
According to the eleventh aspect of the present invention, since the angular accuracy of the side surface of the heat radiating substrate does not affect the emission direction of the light emitting element, the angular accuracy of the side surface of the heat radiating substrate can be reduced, and the angle accuracy of the main substrate to the upper surface of the prism element can be reduced. The distance can be shortened, and the size can be further reduced.
According to the twelfth aspect of the present invention, the integration including the preamplifier can be further performed, and the electric crosstalk between the transmission and reception signals during high-speed modulation can be reduced.
According to the thirteenth aspect of the present invention, since the prism element is fixed on two surfaces, mounting steps such as position adjustment of the prism element can be simplified, and heat radiation of the preamplifier is also improved because the preamplifier is mounted on the heat dissipation substrate. Can be done.
According to the fourteenth aspect, the mounting surfaces of the light emitting element and the light receiving element are in the same direction, so that the mounting process can be simplified.
According to the fifteenth aspect, it is possible to suppress the reception light emitted from the optical fiber from being reflected by the end face of the light receiving element and returning to the optical fiber side. According to the sixteenth aspect, further integration including the output monitoring light receiving element can be performed without changing the distance from the main substrate to the upper surface of the prism element, that is, the external dimensions of the entire module.
According to the seventeenth aspect, since the mounting surfaces of the light emitting element, the light receiving element, and the preamplifier are in the same direction, the mounting process can be simplified.
According to the eighteenth aspect, the prism element can also have the function of the condenser lens, and the configuration can be simplified.
According to the nineteenth aspect, the cap for sealing can also have the function of the fixture for the condenser lens, and the configuration can be simplified.
According to the twentieth aspect, the coupling of the light emitting element and the light receiving element to the optical fiber can be realized only by the optical adjustment of one condenser lens and the optical fiber.
According to the twenty-first aspect of the present invention, it is possible to reduce the size of the optical transmission / reception device and to realize a multi-port optical transmission / reception device in which the optical transmission / reception module is integrated.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of an optical transceiver module according to first and second embodiments of the present invention as viewed from a side.
FIG. 2 is a diagram showing a configuration of the optical transceiver module of FIG.
FIG. 3 is an exploded perspective view showing two substrates of a prism element according to the first and second embodiments of the present invention.
FIG. 4 is a diagram showing a configuration of an optical transceiver module according to a third embodiment of the present invention as viewed from a side.
FIG. 5 is a diagram showing a configuration of an optical transmitting and receiving module according to fourth and fifth embodiments of the present invention as viewed from the side.
FIG. 6 is a diagram illustrating transmittance characteristics of a second wavelength filter according to a fifth embodiment of the present invention.
FIG. 7 is a diagram showing a configuration of an optical transceiver module according to a sixth embodiment of the present invention as viewed from the side.
FIG. 8 is a diagram showing a configuration of an optical transceiver module according to a seventh embodiment of the present invention as viewed from the side.
FIG. 9 is a diagram showing a configuration of an optical transceiver module according to an eighth embodiment of the present invention as viewed from the side.
FIG. 10 is a diagram showing a configuration of an optical transceiver module according to a ninth embodiment of the present invention as viewed from the side.
FIG. 11 is a diagram showing a configuration of an optical transceiver module according to a tenth embodiment of the present invention as viewed from the side.
FIG. 12 is a diagram showing a configuration of an optical transceiver module according to an eleventh embodiment of the present invention viewed from the side.
FIG. 13 is a diagram showing a configuration of an optical transceiver module according to a twelfth embodiment of the present invention as viewed from the side.
FIG. 14 is a diagram showing a configuration of an optical transceiver module according to a thirteenth embodiment of the present invention as viewed from the side.
FIG. 15 is a diagram showing a configuration of an optical transceiver module according to a fourteenth embodiment of the present invention as viewed from the side.
FIG. 16 is a diagram showing a configuration of an optical transceiver according to a fifteenth embodiment of the present invention.
FIG. 17 is a diagram showing a configuration of a conventional optical transceiver module.
[Explanation of symbols]
101 Main board
101a pin
101b Top surface of main board
102, 111, 113 heat dissipation board
102a Reference surface of heat dissipation board
102b Vertical plane of main board
103, 112 Prism element
103a Reference plane of prism element
103b First substrate of prism element
103c Second substrate of prism element
103d Half mirror (optical film) in prism element
103e, 103f Wavelength filter (optical film) in prism element
104 light emitting element
105 light receiving element
106 condenser lens
107 Optical fiber
108 Output monitor photo detector
109 surface emitting element
110 preamplifier
112a Optical film of prism element
112b Adjacent surface of heat dissipation board protrusion 113a in prism element
112c Lens part of prism element
114 Cap for sealing
115 Optical transceiver module
116 Main resin board
117 Optical transmission / reception device housing
118 Optical fiber connector plug
1031 Lower surface of prism element
1032 Top surface of prism element

Claims (21)

A prism element having at least two light-transmissive substrates bonded thereto and having parallel upper and lower surfaces;
Arranged at an interface between the two substrates, transmitting light incident from the lower surface of the prism element in the direction of the upper surface of the prism element, and receiving light incident from the upper surface of the prism element obliquely above the prism element. An optical film that reflects light to
It has an upper surface parallel to the lower surface of the prism element and a surface perpendicular to the upper surface, and the lower surface of the prism element is fixed to the upper surface, or the lower surface parallel to the upper surface is fixed on the main substrate or A radiating substrate integrally formed with the main substrate, and a light emitting element attached to a vertical surface of the radiating substrate and emitting transmission light toward a lower surface of the prism element;
A light receiving element attached to receive the received light reflected obliquely above the prism element on the upper surface of the prism element,
A condenser lens provided between the upper surface of the prism element and the optical fiber,
Optical transmitting and receiving module having. The optical film transmits transmission light emitted from the light emitting element at a certain rate, and receives light emitted from the optical fiber and collected by the condenser lens at a certain rate. The optical transceiver module according to claim 1, wherein the optical transceiver module is a half mirror that reflects light toward the light receiving element. The optical film completely transmits transmission light of a first wavelength emitted by the light emitting element, and has a second wavelength different from the first wavelength emitted from the optical fiber and condensed by the condenser lens. The optical transceiver module according to claim 1, wherein the optical transceiver module is a wavelength filter that totally reflects received light having a wavelength. 4. The light receiving element according to claim 3, wherein the light receiving element has a light receiving sensitivity at a receiving wavelength as the second wavelength and a light receiving sensitivity wavelength dependency sufficiently larger than a light receiving sensitivity at a transmitting wavelength as the first wavelength. An optical transceiver module as described in the above. The optical transceiver according to any one of claims 1 to 4, wherein the light emitting element is mounted on a heat dissipation board so that an emission direction of transmission light is slightly inclined with respect to an optical axis of an optical fiber. module. The optical transmission / reception module according to any one of claims 1 to 5, wherein an antireflection film is coated on a position on the outer wall surface of the prism element through which transmission / reception light is transmitted. The optical transceiver module according to any one of claims 1 to 6, wherein a light shielding film is provided on an upper surface that is a surface opposite to a light receiving surface of the light receiving element. The optical transceiver module according to any one of claims 1 to 7, wherein an output monitoring light receiving element is mounted at a position on the main substrate at which the rear emission light of the light emitting element can be received. 8. A light-receiving element for output monitoring is mounted on a side surface of the prism element capable of receiving the light reflected by the optical film on the transmission light emitted from the light-emitting element. The optical transmitting / receiving module according to claim 1. 8. The optical transceiver according to claim 2, wherein the light receiving element receives both the reception light and the transmission light and also serves as a light receiving element for monitoring the output of the light emitting element. module. 11. The light emitting device according to claim 1, wherein the light emitting element has a structure for emitting transmission light in a direction perpendicular to a mounting surface, and is mounted on the main substrate instead of the vertical surface of the heat radiation substrate. The optical transceiver module according to any one of the above. The optical transceiver module according to any one of claims 1 to 10, wherein a preamplifier is mounted near the light receiving element on the upper surface of the prism element to amplify and output an output current of the light receiving element. . The upper surface side of the heat dissipation substrate is formed so that the side surface and the lower surface of the prism element can be fitted together, and the upper surface of the heat dissipation substrate and the upper surface of the prism element are substantially flush with each other. 13. The optical transceiver module according to claim 12, wherein the optical transceiver module is mounted on the upper surface of the heat dissipation board instead of the upper surface of the element. The optical film, instead of reflecting the transmission light incident from the upper surface of the prism element obliquely upward of the prism element, and arranged to reflect in a substantially horizontal direction, and the light receiving element of the upper surface of the prism element 14. The optical transceiver module according to claim 1, wherein the light transmitting and receiving module is disposed on a side surface of the prism element in the same direction as the light emitting element. 13. The optical transceiver module according to claim 14, wherein an angle of the optical film with respect to the main substrate is an acute angle shifted from 135 degrees. The optical film is configured to reflect a part of the transmission light incident from the lower surface of the prism element in a direction opposite to the light receiving element, and on a side surface of the prism element opposite to the mounting surface of the light receiving element. 16. The optical transceiver module according to claim 14, wherein a light receiving element for output monitoring is mounted. The upper surface side of the heat radiating substrate is formed so that the side surface and the lower surface of the prism element can be fitted together, and the side surface of the heat radiating substrate and the side surface of the prism element are substantially the same, and the light receiving element, 17. The optical transceiver module according to claim 14, wherein a preamplifier is mounted on each of the side surfaces of the prism element and the heat dissipation board. The optical transceiver module according to any one of claims 1 to 17, wherein the condenser lens is integrally formed on an upper surface of the prism element, and optically coupled directly from the prism element to the optical fiber. . The heat radiation substrate and the prism element mounted on the main substrate are hermetically sealed by covering with a cap, and the condenser lens is provided in an opening window on the optical fiber side of the cap. 18. The optical transceiver module according to any one of 1 to 17. The light-emitting element is mounted on the heat-dissipating substrate located on the main substrate, and the light-receiving element is mounted in alignment with a center point of the optical film on the prism element, and the light-emitting element and Electrical connection of the light receiving element to enable power supply,
Next, the prism element is mounted on the heat dissipation substrate with the emission point of the light emitting element and the center point of the optical film being aligned with each other,
Next, the light emitting element emits light, and the condenser lens is fixed to the main substrate so that coupling with the condenser lens is maximized,
Finally, the position of the optical fiber is finely adjusted so that the coupling efficiency of the light emitted from the light emitting element to the optical fiber is maximized, and the optical fiber is fixed to the main substrate. Item 20. A method for mounting the optical transceiver module according to any one of Items 1 to 19. An optical transmitting / receiving apparatus comprising one or more optical transmitting / receiving modules according to any one of claims 1 to 18.

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