JP3349631B2 - Optical transceiver module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission / reception module for optical communication, and more particularly to an optical transmission / reception module in which a light emitting element, a light receiving element, and an optical branching element are integrated.

[0002]

2. Description of the Related Art With the spread of digital telephone lines and CATV (cable television) capable of transmitting high-speed and large-capacity information to the general public, not only in trunk systems but also in terminal subscriber systems. In addition, a shift from a conventional transmission method using a metallic cable to a transmission method using an optical fiber cable is being advanced.

FIG. 11 shows one of transmission systems using an optical fiber, in which a connection between a station side device 101 and a subscriber side device 102 is established.
A transmission method in which two optical communications are performed by being tied by one optical fiber 103 is shown. In this method, light in the 1.3 μm band is
Light in the 1.55 μm band is used for one-way communication such as CATV broadcasting for bidirectional communication such as digital telephone and ISDN (Integrated Services Digital Network). In order to connect a plurality of subscribers, it is necessary to further branch the transmission line by a star coupler or the like, but this is omitted in FIG. In FIG. 11, the same components of the optical line terminal 101 and the subscriber side device 102 are denoted by the same reference numerals.

In this transmission system, a transmission optical signal (dashed arrow) in the 1.55 μm band emitted from a light emitting element 104 in a station side device 101 passes through an optical fiber 103 and enters a subscriber side device 102. , Through a multiplexing / demultiplexing element 105 that separates wavelengths of light in the 1.3 μm band and light in the 1.55 μm band, and is received by the light receiving element 106 in the 1.55 μm band. Further, a 1.3 μm band transmission optical signal (solid arrow) emitted from the light emitting element 107 in the optical line terminal 101 or the subscriber side device 102 passes through the optical fiber 103, and the multiplexing / demultiplexing element 105 of the other party respectively. Through the light splitting element 108 and 1.
The light is received by the 3 μm band light receiving element 109.

FIG. 12 shows an example (NT) of a conventional optical transmission / reception module on the subscriber side used in the information transmission system as described above.
T Technical Report Vol. 42 No. 7, 1993). In the optical transmission / reception module 200 on the subscriber side, the optical fiber 2
The optical signals of 1.3 μm band and 1.55 μm band transmitted through 09 are wavelength-separated by a Mach-Zehnder multiplexer / demultiplexer 201 formed on the waveguide, and the optical signal of 1.55 μm band is Is taken out of the package 212 through
It is detected by a 1.55 μm band receiving optical module (not shown) provided in front of it. On the other hand, an optical signal in the 1.3 μm band travels straight through the waveguide and is branched into two by the directional coupler 202.
A part thereof is detected by the photodiode 204. Here, the reason why the 1.55 μm band receiving optical module is not integrated with the 1.3 μm band optical transmitting / receiving module 200 is that the 1.55 μm band receiving optical module can be detached according to the usage form of the subscriber. It is.

A 1.3 μm band optical signal emitted from the subscriber side laser diode 205 passes through the spherical fiber 211, the directional coupler 202, and the multiplexing / demultiplexing element 201, and then passes through the optical fiber 20.
It is transmitted to the optical line terminal through 9.

FIG. 13 (a) is a view similar to that of FIG.
Japanese Unexamined Patent Publication No.
FIG. 13 (b) is an enlarged view of a hologram optical element 327 which constitutes a part of the optical transmission / reception module described in JP-A-138322. In FIGS. 13 (a) and 13 (b), 1.3 μm transmitted from the station side is used.
The optical signals of the m band and the 1.55 μm band pass through an optical fiber 309 held by an optical fiber holder 320, enter a package 312, and enter a collimating lens 3 serving as a condensing element.
After being converted into a parallel light beam by the hologram optical element 327, the light beam enters the interference film filter 325 formed on the surface of the trapezoidal column glass substrate 327a of the hologram optical element 327. And in the optical signal
Only the light beam in the 1.55 μm band is
The reflected light 330 is reflected by another collimating lens 3
The light is taken out of the package 312 through the optical fiber 310 and the optical fiber 310, and is detected by a receiving optical module (not shown) provided at the end. On the other hand, light in the 1.3 μm band that is not reflected by the interference film filter 325 passes through the interference film filter 325, and the lens 3 formed on the glass substrate 327a.
After being condensed by 24, the light is diffracted by a hologram diffraction grating 326 formed on the back surface of the glass substrate 327a, becomes a first-order diffracted light 332, and is condensed on the photodiode 304 and detected.

On the other hand, an optical signal 331 in the 1.3 μm band emitted from the semiconductor laser 305 on the subscriber side is a hologram diffraction grating.
The light passes through 326 as the 0th-order diffracted light, is converted into parallel light by a lens 324, and is transmitted to a station side device (not shown) via a collimator lens 322 and an optical fiber 309. In the optical transceiver module 300 of FIG. 13, the interference film filter 325 is used as a multiplexing / demultiplexing element.
A hologram diffraction grating 326 is used as each of the light splitting elements.

FIGS. 14 (a) and 14 (b) show still another conventional example of an optical transmitting / receiving module on the subscriber side.
No. 104154 is disclosed. In this optical module, multiplexing / demultiplexing and branching of light are simultaneously performed by a hologram optical element 426. That is, at the time of reception, the long wavelength λ incident from the optical fiber 409 is used.
_{Since the} signal light including the light beam 433 of ₂ (1.55 μm) and the light beam 434 of short wavelength λ ₁ (1.3 μm) passes through the lens 422 and is collected, the diffraction angle varies depending on the length of the wavelength. Then, the light is separated into a light beam 435 and a light beam 436 as first-order hologram diffracted light by the diffraction grating of the hologram optical element.
Each is incident on 04 and detected. Also, when sending,
As shown in FIG. 14B, the light beam 431 of wavelength λ ₁ emitted from the semiconductor laser element 405 is
The light passes through 26, passes through the lens 422 as hologram 0th-order diffracted light, enters the optical fiber 409 as signal light 432, and is transmitted to the optical line terminal (not shown).

[0010]

The conventional optical transmission / reception modules shown in FIGS. 12 and 13 each have a structure in which an optical module dedicated to reception can be attached and detached, so that a module according to the usage form of the subscriber can be provided. There is an advantage. However, the optical transceiver module shown in FIG.
The 200 uses a waveguide-type element as a multiplexing / demultiplexing element or an optical branching element, and many manufacturing processes such as core layer formation, photolithography, etching, cladding deposition and sintering are used to form a waveguide. Since it is required, there is a problem that it is difficult to reduce the cost and the optical transmitting and receiving module becomes expensive.

In the conventional optical transceiver module 300 shown in FIG. 13, an interference film filter 325 as a multiplexing / demultiplexing element and a hologram diffraction grating 326 as an optical branching element are formed on a glass substrate 327a polished into a trapezoidal column shape. Therefore, it is not possible to perform a batch process for each of the steps of “fabrication of lens (ion exchange method) and fabrication of interference film filter (vapor deposition method)” or “production of hologram diffraction grating” for each wafer. It is possible. Therefore, mass production of the hologram optical element 327 is difficult, and the production cost increases.

Further, in the case of the conventional optical transmitting / receiving module shown in FIG. 14, a hologram optical element 426 is used similarly to the optical transmitting / receiving module 300 of FIG. 13, but this hologram optical element 426 has a diffraction grating on a flat substrate. , Mass production on a wafer basis is possible.
Therefore, the production cost can be reduced accordingly. However, the long wavelength light 433 in the 1.55 μm band and the short wavelength light 434 in the 1.3 μm band are respectively transmitted to the photodiode 40.
There is the following problem because it is configured to detect at 3,404. That is, in the case of receiving a weak and high-frequency signal, from the viewpoint of suppressing noise, it is preferable that the amplifier circuit and the detection circuit be mounted in the immediate vicinity of the photodiodes 403 and 404.
It is difficult to separately install the 55 μm band receiving optical module. Therefore, 1.55μ depending on the usage form of the subscriber
It is difficult to make the m-band optical receiving module detachable, and there is a problem that an optical transmitting and receiving module having a wide price system cannot be provided.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical transmitting / receiving module in which a receiving-only optical module can be detachably mounted and which can be manufactured easily and at low cost.

[0014]

According to a first aspect of the present invention, there is provided an optical transceiver module comprising: first and second optical fiber connection ports provided in a package; and a first optical fiber connection port. A condensing element for condensing the light of the first wavelength and the light of the second wavelength sent into the package from the light source, and a light of the first wavelength and a light of the second wavelength condensed by the light condensing element. A hologram optical element that diffracts light in different directions, a light-receiving element that receives the light of the first wavelength that is first-order diffracted by the transmission hologram optical element, and the light that is first-order diffracted by the transmission hologram optical element. Upon receiving the light of the second wavelength, regardless of the angle of incidence of the light of the second wavelength, the reflected light is directed to enter the second optical fiber connection port via the hologram optical element and the condensing element. A parabolic mirror as a light reflecting element which is characterized by comprising a light emitting element that emits light of a first wavelength sent out from the first optical fiber connection port.

In the optical transceiver module having the above configuration, the first wavelength light and the second wavelength light sent into the package from the first optical fiber connection port pass through the light-collecting element and then pass through the transmission type. The light enters the hologram optical element. This transmission type hologram optical element diffracts incident light at a diffraction angle corresponding to the wavelength, thereby forming light of the first wavelength and light of the second wavelength.
Separate into light of wavelength. At the same time, the transmission type hologram optical element diffracts light of each wavelength as each order diffracted light, and makes only the first order diffracted light incident on the light receiving element and the light reflecting element, respectively. In other words, the transmission hologram optical element performs both wavelength separation (light splitting) and light branching. Therefore, the number of components is smaller than that of a conventional optical transmission / reception module in which these two functions are realized by separate components, and the transmission hologram optical element can be mass-produced on a wafer basis. It is possible to reduce the size and cost.

The light of the second wavelength separated by the transmission hologram optical element is reflected by a rotating parabolic mirror as a light reflecting element. This light reflecting element has its second
Irrespective of the incident angle of the wavelength, the reflected light is reflected so as to be incident on the second optical fiber connection port via the hologram optical element and the light condensing element. Even if the generated light is displaced, the light of the second wavelength efficiently enters the second optical fiber connection port. Accordingly, a decrease in the detection light intensity is suppressed. Further, since the light of the second wavelength incident on the second optical fiber connection port is taken out of the package of the optical transmission / reception module, a dedicated module for receiving the light of the second wavelength can be detachably attached. Therefore, it is possible to provide a low-cost module omitting the second-wavelength light receiving function according to the use mode.

According to a second aspect of the present invention, the light transmitting / receiving module is characterized in that the condensing element and the transmission hologram optical element are integrated.

According to the second aspect of the present invention, it is possible to further reduce the size of the module, and to reduce the number of adjustment points and the adjustment time when assembling the module. Further, by simultaneously manufacturing the light-collecting element and the transmission hologram optical element, the number of manufacturing steps can be reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments.

FIG. 1 is a sectional view of a subscriber-side optical transceiver module according to a first embodiment of the present invention, and FIG. 2 is a perspective view thereof. FIG. 3A is an enlarged sectional view of a main part of the optical transceiver module. 1 and 2, a semiconductor laser 1 as a light emitting element, a photodiode 2 as a light receiving element, and a rotating parabolic mirror 3 as a light reflecting element are provided on a submount 4, and the submount 4 is mounted on a package 12. It is mounted on a fixed stem 5.

The above submount 4 is shown in FIGS. 3 and 7 (a).
As shown in the figure, the front surface has an inclined surface 4a of about 10 °, and the rotating parabolic mirror 3 is formed on the inclined surface 4a.
The photodiode 2 is formed on a flat surface following the inclined surface 4a, and the semiconductor laser 1 is formed on a side surface of the submount 4 adjacent to the flat surface. The semiconductor laser 1, the photodiode 2, and the rotating parabolic mirror 3 are arranged as shown in FIG.
As shown in the figure, they are arranged on a straight line at an interval from each other. The semiconductor laser 1, the photodiode 2, and the paraboloid of revolution 3 are hermetically sealed by a cap 7 to which a hologram optical element 6 is attached. As shown in FIGS. 3A and 5, the hologram optical element 6 includes a glass substrate 6a and a hologram diffraction grating 6b having a rectangular cross section formed on the glass substrate 6a. A lens 8 as a light condensing element is fixed to the package 12 adjacent to the hologram optical element 6. The semiconductor laser 1 is located on the optical axis of the lens 8. Stem 5 of package 12
On the opposite end, a 1.3 μm transmission / reception optical fiber 9 is provided.
A fiber holder 11 for connecting and fixing the receiving optical fiber 10 in the 1.55 μm band is attached. The optical fiber 9 is connected to an optical line terminal (not shown), and the optical fiber 10 is connected to a 1.55 μm band receiving optical module (not shown) that is detachable according to the application.

The rotary parabolic mirror 3 is manufactured by cutting and polishing a copper block to produce a submount 4, and then providing a concave portion in the shape of a parabolic mirror by etching on the inclined surface 4a of the submount 4. It is manufactured by depositing gold on this concave surface.

The hologram diffraction grating 6b is manufactured by forming a resist pattern on a glass wafer by photolithography and then performing reactive ion etching. Therefore, in the method of manufacturing the hologram optical element 6 described above, several hundred hologram optical elements 6 can be simultaneously manufactured at a time, so that the manufacturing cost can be reduced.

FIG. 6 shows the diffraction angle θ of the hologram diffraction grating 6b.
And the relationship between the distance L and the focusing position h. In the figure, the hologram diffraction grating 6b is provided on the right side of the glass substrate 6a, but may be provided on the left side. The relationship between the diffraction angle θ of the primary light of the hologram optical element for each wavelength λ and the pitch の of the hologram diffraction grating 6b (see FIG. 5B) is generally expressed by the following equation.

Sin θ = λ / Λ where the pitch of the hologram diffraction grating 6 b Λ = 7.5 μm,
Distance L = 1 between semiconductor laser 1 and hologram diffraction grating 6b
0 mm, light beam wavelength λ ₁ = 1.31 μm, λ ₂ = 1.55 μm
, The diffraction angles θ1 = 10.0 °, θ2 = 11.9 °, the condensing positions h1 = 1.76 mm, h2 = 2.11 mm, and the light reflecting element 3
And the photodiode 2 can be separated by 0.35 mm.

FIG. 3A shows the propagation path of a light beam during transmission.
(White arrow) and the propagation path of the light beam during reception (black arrow). FIGS. 3B and 3C are diagrams showing the propagation paths of the 1.3 μm band and 1.55 μm band light beams incident on the lens optical axis in the case of reception. With reference to these figures, the operation of the optical transceiver module of the present invention will be described below.

As shown by the white arrow in FIG. 3A, when transmission is performed, the 1.3 μm band transmission light beam 20 emitted from the semiconductor laser 1 enters the hologram optical element 6.
The 0-order diffracted light transmitted through the hologram optical element 6 is condensed by the lens 8 and becomes a light beam 21 as indicated by an arrow B in the figure.
, And enters the optical fiber 9 (see FIG. 1) and is transmitted to the optical line terminal.

On the other hand, when performing reception, as shown by the black arrow in FIG.
The m-band and the 1.55 μm-band receiving light beam 21 travel in the opposite direction to the above-described transmission, that is, in the direction of arrow A in the figure,
The light is condensed by the lens 8 and enters the hologram optical element 6. The incident light beam passes through the diffraction grating 6b of the hologram optical element 6, and is diffracted at different angles depending on the wavelength and is separated from each other. As a result, the 1.3 μm band light beam (1.3 μm band first-order diffracted light) 22 represented by the dashed line is condensed on the photodiode 2 and detected by the photodiode 2. Meanwhile, 1.
The 55 μm band light beam (1.55 μm band first-order diffracted light) 23 is
The light is focused on the rotating parabolic mirror 3. On the other hand, the light 23 incident on the rotating parabolic mirror 3 is reflected by the rotating parabolic mirror 3, travels in the direction of arrow B, and enters the hologram optical element 6 again. This incident 1.55 μm band light beam 2
3 is 1 by the diffraction grating 6b of the hologram optical element 6.
The 0th-order diffracted light 24 indicated by the broken line is incident on the optical fiber 10 (see FIG. 1), and the 1.55 μm band receiving optical module (not shown) is divided therefrom.
Is propagated to

By the way, generally, when there is a change in the wavelength,
The diffraction angle of the light by the hologram optical element 6 changes, and the light incident position on the light reflecting element 3 shifts. Alternatively, even if the wavelength does not change, if the interval between the hologram diffraction gratings changes due to a change in temperature, the diffraction angle of the light changes, and the light to the light reflecting element 3 is changed in the same manner as when the wavelength changes. Is shifted. However, in the present embodiment, since the light reflecting element is constituted by the rotating parabolic mirror, even if the light beam incident on the light reflecting element 3 is displaced due to a change in the diffraction angle, the light reflecting element 3 is incident. Light can be reflected in a direction close to the design position, the reflected light can be efficiently incident on the optical fiber end 10, and a decrease in detected light intensity can be suppressed.

As described above, in the optical transceiver module according to this embodiment, one hologram optical element 6 has two functions, that is, the multiplexing / demultiplexing and branching of the light beam. Therefore, the number of components can be reduced, and the size of the module can be reduced. The hologram optical element 6
Can be manufactured in wafer units since the diffraction grating 6b is formed on the flat glass substrate 6a, and the manufacturing cost of the module can be reduced. Further, since the received light in the 1.55 μm band is taken out of the optical transceiver module by being reflected by a rotating parabolic mirror,
A band receiving module (not shown) can be made detachable.

In the above-described embodiment, a rotating parabolic mirror, which is a kind of a concave mirror, is used as the light reflecting element. However, the reflecting element may have any shape that allows reflected light to efficiently enter the end of the optical fiber 10. Any other concave mirror may be used.

In the above-described embodiment, the submount 4 is formed by one block. However, as shown in FIG. 7B, a triangular block 4b having the parabolic mirror 3 is formed in advance. Alternatively, the submount 4 may be manufactured by attaching this to a rectangular parallelepiped block.

FIG. 8A shows a light reflecting element according to the second embodiment of the present invention. Since the components other than the light reflecting element are the same as those in the first embodiment,
Description is omitted.

This light reflection element is made of a reflection type hologram optical element. The reflection type hologram optical element 3b shown in FIG. 8 (a) is mounted on the inclined surface 4a of the submount 4, and the cross-sectional shape of the diffraction grating is the same as the transmission type hologram diffraction grating 6b shown in FIG. 5 (b). It is also rectangular, but gold is deposited on the surface on the hologram diffraction grating side.
This reflection type hologram optical element 3b is
The pattern is designed to perform the same function as,
The incident light is first-order diffracted by the reflection type hologram optical element 3b. Thereafter, as shown in FIG. 3A, the light enters the transmission hologram optical element 6 again, and enters the optical fiber 10. On the other hand, in FIG. 8B, the reflection hologram optical element 3c is mounted on a rectangular parallelepiped submount 4 'having no inclined surface 4a. Reflection type hologram optical element 3c
Has a hologram diffraction grating pattern different from that of the reflection type hologram optical element 3b of FIG. 8 (a), and can perform the same function as that provided on the inclined surface even when located on the horizontal plane. . In this case, the processing of the inclined surface of the submount can be omitted, and the thickness of the submount can be reduced. Further, since the concave mirror 3 such as the rotating parabolic mirror used in the first embodiment is formed directly on the submount 4,
Although it is necessary to fabricate the reflective hologram optical elements 3b and 3c in a large amount by using a wafer, the production cost can be reduced.

FIG. 9 shows a lens 80 with a hologram diffraction grating in which a hologram diffraction grating 6b is integrally formed on the exit surface side of the lens 8a as a third embodiment. This hologram diffraction grating-equipped lens 80 is manufactured by a method of simultaneously manufacturing a lens and a hologram diffraction grating by resin injection molding,
Alternatively, the hologram diffraction grating is formed by a method using a stamper called a 2P method after forming a lens, and a method of forming a hologram diffraction grating with an ultraviolet curable resin. By integrating the hologram diffraction grating 6b and the lens 8a, it is possible to reduce the size of the module and reduce the number of adjustment points and adjustment time during assembly.

FIG. 10 shows a hologram optical element 6 'used in place of the hologram optical element shown in FIG. The grating groove pitch の of the diffraction grating 6c of the hologram optical element 6 'is the same as that shown in FIG. 5, but has a sawtooth cross section. In the present optical transceiver module, signal detection is performed using only the first-order diffracted light.
It is desirable to increase only the intensity of the second order diffracted light. Therefore,
In the hologram optical element 6 'shown in FIG. 10, the hologram diffraction grating 6c has a sawtooth cross-sectional shape, and the first-order diffracted light and -1
By changing the intensity balance of the light with the second-order diffracted light, only the intensity of the first-order diffracted light is increased. FIG.
, The light beam 21 in the 1.3 μm band that has passed through the lens 8
Enters the sawtooth-shaped hologram diffraction grating 6c, and branches into a 0th-order diffracted light 20, a 1st-order diffracted light 22, and a -1st-order diffracted light 25. The first-order diffracted light 22 in the 1.3 μm band is detected by the photodiode 2 installed on the submount 4. This saw-tooth hologram diffraction grating 6c provides
The intensity of the second-order diffracted light 22 can be reduced to about 30% of the total diffracted light, and the intensity of the unnecessary -1st-order diffracted light 25 can be reduced to about 10% or less.
Detection efficiency can be improved.

The case where the first-order diffracted light 22 having a wavelength of 1.3 μm enters the photodiode 2 has been described above. The same applies to the case where the first-order diffracted light 23 having a wavelength of 1.55 μm enters the light reflecting element 3. Is obtained, that is, the intensity of the first-order diffracted light is increased, and the detection efficiency of the light beam can be improved.

Also, in the reflection type hologram optical elements 3b and 3c shown in FIG. 8 and the lens with hologram diffraction grating 80 shown in FIG. 9, the diffraction grating has a sawtooth cross-sectional shape so that the diffraction light to be detected can be detected. The intensity can be increased, and the detection efficiency of the light beam can be improved.

In each of the above embodiments, the 1.3 μm band and the 1.55 μm band are used.
Although the transmission and reception of the m-band optical signal has been described, it is needless to say that the present invention can be applied to the transmission and reception of an optical signal of another wavelength.

[0040]

As is apparent from the above description, the optical transceiver module of the first aspect allows the transmission hologram optical element to perform two functions of wavelength separation (optical demultiplexing) and optical branching. The number of components is smaller than that of a conventional optical transmission / reception module in which two functions are realized by separate components, so that the transmission type can be reduced in size and cost, and can be mass-produced in wafer units. Since the hologram optical element is used, the cost can be reduced.

In the optical transmitting / receiving module according to the first aspect of the present invention, the second wavelength light separated by the transmission hologram optical element is converted into a second wavelength light by a rotating parabolic mirror serving as a light reflecting element. Irrespective of the angle of incidence, the reflected light is reflected so as to be incident on the second optical fiber connection port via the hologram optical element and the condensing element, so that the light incident on the light reflecting element due to a manufacturing error or a temperature change. Even if the position shift occurs, the light of the second wavelength efficiently enters the second optical fiber connection port, and a decrease in the detection light intensity can be suppressed.

Further, the optical transceiver module of the first aspect of the present invention takes out the light of the second wavelength incident on the second optical fiber connection port out of the package of the optical transceiver module, thereby receiving the light of the second wavelength. A dedicated module can be made detachable, and a low-cost module without the second-wavelength light receiving function can be provided according to the use form.

In the optical transmission / reception module according to the second aspect, since the light-collecting element and the transmission-type hologram optical element are integrated, the module can be further reduced in size. Can be reduced. In addition, since the light-collecting element and the transmission hologram optical element are manufactured at the same time, the number of manufacturing steps can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an optical transceiver module according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the first embodiment.

FIG. 3 is an explanatory diagram showing propagation of a light beam in the first embodiment.

FIG. 4 is a plan view of a submount provided with a paraboloid of revolution, a photodiode, and a semiconductor laser according to the first embodiment.

5A and 5B show the hologram optical element according to the first embodiment, wherein FIG. 5A is a front view thereof, and FIG. 5B is a sectional view taken along line bb of FIG. 5A.

FIG. 6 is a diagram showing a relationship among a hologram diffraction grating, a diffraction angle, and a light-converging position in the first embodiment.

FIG. 7 is a perspective view of a submount including a paraboloid of revolution, a photodiode, and a semiconductor laser according to the first embodiment.

FIG. 8 is a perspective view of a submount including a reflection hologram optical element according to a second embodiment of the present invention.

FIG. 9 shows a hologram diffraction grating-integrated condensing element according to a third embodiment of the present invention.
(b) is a perspective view.

FIG. 10 is a cross-sectional view of a peripheral portion of a hologram optical element showing a relationship between a sawtooth hologram diffraction grating and diffracted light according to a fourth embodiment of the present invention.

FIG. 11 is a diagram showing an example of an optical fiber communication system between a station side and a subscriber side.

12 is a configuration diagram showing a conventional example of an optical transmission / reception module used for the communication system of FIG.

FIG. 13 is a configuration diagram showing another conventional example of an optical transceiver module.

FIG. 14 is a configuration diagram showing another conventional example of an optical transceiver module.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor laser, 2 ... Photodiode, 3 ... Rotating parabolic mirror, 3b, 3c ... Reflection type hologram optical element,
4, 4 ': submount, 5: stem, 6, 6': transmission hologram optical element, 6a: glass substrate, 6b, 6
c: hologram diffraction grating, 7: cap, 8, 8a
… Lens, 9… 1.3μm band optical fiber for transmission and reception, 10
… 1.55μm receiving optical fiber, 11… Fiber holder, 12… Package.

Claims (2)

(57) [Claims] A first optical fiber connection port provided in the package; and a first wavelength light and a second wavelength light sent into the package from the first optical fiber connection port. A condensing element that emits light; a transmission hologram optical element that diffracts the light of the first wavelength and the light of the second wavelength condensed by the light condensing element in different directions; A light receiving element that receives the diffracted light of the first wavelength; and a light receiving element that receives the light of the second wavelength that is first-order diffracted by the transmission hologram optical element and reflects the light regardless of the incident angle of the light of the second wavelength. A rotating parabolic mirror as a light reflecting element for reflecting light so as to be incident on a second optical fiber connection port via the hologram optical element and the light condensing element, and transmitted from the first optical fiber connection port. Optical transceiver module, characterized by comprising a light emitting element that emits light of a first wavelength issued. 2. The light-collecting element and the transmission-type hologram light.
2. The element according to claim 1 , wherein the element is integrated.
The optical transceiver module according to item 1.