JP2003069124A - Bidirection optical transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem; the difficulty of miniaturization of an optical transmission device since an optical transmitting/receiving device is separate and two optical fibers are used. SOLUTION: Two spot-faced grooves 18A, 18B which stand in a line along an optical transmission direction are formed in an upper surface of one base substrate 16 with a through-hole electrode 17. An LED 7 or an LD is mounted on a bottom of one spot-faced groove 18A, and an IC 12 which is a photosensitive element is mounted on a bottom of the other spot-faced groove 18B. A partition 16A formed between two spot-faced grooves 18A, 18B constitutes a light screening wall which prevents optical interference between both chips. Plating coating 19 is applied to a surface of the spot-faced grooves 18a, 18b. A block 20 (metal/plastic) is sub-mounted on a rear of the IC 12. An optical transmission hole of a transmitting/receiving device 15 is airtightly closed by a lens 23 (glass/plastic). A miniaturized and inexpensive single bidirection optical transmission device which enables surface mounting can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bidirectional optical transmission device capable of communicating by engaging an optical fiber plug with an optical minijack or an optical transmission module, and more specifically, to a single-core optical fiber. The present invention relates to a single-core bidirectional optical transmission device for transmitting optical signals as data.

[0002]

2. Description of the Related Art In recent years, there have been minijacks and transceiver type modules in which a light emitting device and a light receiving device are combined in a housing. Minijack modules are used in CD players, MD players, notebook PCs, etc., and transceiver modules are used in home appliances such as routers, modem stations, notebook PCs, and the like. These optical transmission modules currently on the market use one optical fiber, one-core one-way communication with a light emitting device and a light receiving device facing each other, and two optical fibers, and separate transceiver modules (two). There is a two-core two-way communication structure, both of which are large and lead frame type. No small-sized, surface-mount type, one-core bidirectional optical transmission module is found.

5 and 6 show the structure of a conventional general bidirectional optical transmission device, and FIG. 5 is a cross-sectional view of a main part of a bidirectional optical transmission module. FIG. 6 is an explanatory view from the direction of arrow A in FIG.

In FIGS. 5 and 6, reference numeral 1 is an optical fiber plug, and the optical fiber plug 1 has a housing part 2
Book optical fibers 2a and 2b are stored.

Reference numeral 3 denotes an optical transmission module. In the optical transmission module 3, a light emitting device 5 in which a light emitting chip is mounted inside a housing 4 and a light receiving device 10 in which a light receiving chip is mounted are integrated by a single housing 4. It has become. The light emitting device 5 includes three lead frames 6
Light emitting diode (LED) 7 or laser (LD) as a light emitting chip on the surface of (6a, 6b, 6c) (FIG. 6)
And a drive IC 8 for controlling the LED 7 or LD
Are mounted, and electrical continuity with the lead frames 6a, 6b, 6c is achieved by wires. The LED 7 or LD, the IC 8 and the wire are sealed with a transparent sealing resin 9.

In the light receiving device 10, a photodiode (PDi) having a function of converting an optical signal into an electric signal is integrated on the surface of three lead frames 11 (11a, 11b, 11c) (FIG. 6). IC12 is mounted,
Wires are used to connect to the lead frames 11a, 11b, 11c. The IC 12 and the wires are sealed with a translucent sealing resin 9.

The three lead frames 6a on the light emitting side,
6b, 6c and three lead frames 11a on the light receiving side,
Both 11b and 11c are arranged in parallel on the same plane and project downward from the lower surface of the housing 4.

The three lead frames 6a on the light emitting side,
Of 6b and 6c, the lead frame 6a is a signal input terminal, the lead frame 6b is a power supply terminal, and the lead frame 6
c is a ground terminal. Also, of the three lead frames 11a, 11b, 11c on the light receiving side, the lead frame 1
Reference numeral 1a is a power supply terminal, lead frame 11b is a ground terminal, and lead frame 11c is a signal output terminal.

With the configuration described above, an electric signal is input to the lead frame 6a on the light emitting device 5 side and converted into an optical signal by the IC 8 and LED 7 in the light emitting device 5. L
The light emitted from the ED 7 enters the optical fiber 2a of the optical fiber plug 1 and is transmitted. Next, the optical fiber 2
The light transmitted from b is the IC 12 in the light receiving device 10.
It is incident on the photodiode part of the above and is converted into an electric signal and outputted to the lead frame 11c.

[0010]

However, the bidirectional optical transmission device described above uses two optical fibers, which increases the cost. Further, since the optical transmission / reception device is separate, it is difficult to miniaturize the optical transmission device.
Furthermore, since the optical transmission / reception device is an insertion mounting component using a lead frame, there are various problems such as a large number of mounting steps.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to integrate an optical transmission / reception device, prevent optical interference, and efficiently transmit an optical input / output. Enables optical transmission. It is a surface-mount type device that is compatible with reflow and provides a small-sized and inexpensive single-core bidirectional optical transmission device.

[0012]

In order to achieve the above object, a one-core bidirectional optical transmission device according to the present invention mounts a light emitting chip and a light receiving chip and integrates them by a single housing to electrically connect with the outside. An optical minijack or an optical transmission module having electrode terminals for connection, and a bidirectional optical transmission device in which an optical fiber plug is engaged with the optical minijack or the optical transmission module, wherein the optical minijack or the optical transmission module is Two grooves arranged in parallel along the light transmission direction at a predetermined position between both chips mounted on the upper surface of one base substrate having through-hole electrodes which are electrode terminals for electrical connection with the outside. -Shaped counterbore groove is formed, the light emitting chip is mounted on the bottom surface of the one counterbored groove, and the light receiving chip is mounted on the bottom surface of the other counterbored groove to form the respective optical transmission lines. The partition formed between the two counterbore grooves has a function of a light blocking wall for preventing optical interference between the chips, and a single-core optical fiber plug is engaged with the optical minijack or the optical transmission module. It is characterized by.

Further, the present invention is characterized in that the surfaces of the two counterbore grooves formed on the base substrate are plated.

Further, a block made of a metal block or a plastic block is sub-mounted on the back surface of the light receiving chip.

Further, the block is characterized by being a heat-dissipating / conductive member.

Further, the present invention is characterized in that the optical transmission hole formed in the front surface of the case of the optical minijack or the optical transmission module is sealed with a lens made of glass or plastic.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A bidirectional optical transmission device according to the present invention will be described below with reference to the drawings. 1 to 4 relate to a bidirectional optical transmission device according to an embodiment of the present invention, FIG. 1 is a cross-sectional view of a main part of a one-core bidirectional optical transmission device, FIG. 2 is a perspective view of a transmission / reception device, 3 is a top view of the transmission / reception device housed in the case, and FIG. 4 is a cross-sectional view of the transmission / reception device taken along the line AA of FIG. In the drawings, the same members as those in the conventional technique are designated by the same reference numerals.

In FIG. 1, an optical fiber plug 1A has a single-core optical fiber 2 made of, for example, a plastic material, built in a housing portion. On the other hand, inside the housing 4 of the optical transmission module 3A, a transmission / reception device 15 in which a transmission device and a reception device are integrated on one base substrate is housed, and the front end side of the optical fiber 2 and the front side of the optical element are accommodated. And are placed as close together as possible.

1 to 4, a plurality of semicircular through-hole electrodes 17, which are electrode terminals for electrical connection with the outside, are provided on the side surface of a base substrate 16 made of glass epoxy resin or ceramic. Has been formed. On the upper surface side of the base substrate 16, two grooved countersinks 18A and 18B are formed in parallel at a predetermined position along the light transmission direction, and light is reflected on the surfaces of these countersinks 18A and 18B. A plating coating 19 is applied to improve efficiency. Then, a light emitting diode (LED) 7 or a laser (L) is formed as a light emitting chip on the bottom surface of one of the countersunk grooves 18A.
D) is mounted, and electrical continuity with the upper surface electrode formed on the substrate is performed by a wire. The countersunk groove 18A constitutes a transmission line of the LED 7.

Further, a light receiving chip is mounted on the bottom surface of the other countersunk groove 18B, and the IC 12 having a function of converting a light signal into an electric signal by mounting a photodiode (PDi) and an IC as a light receiving chip is mounted. . The IC1
A plastic block or a metal block as the block 20 on the back surface of the IC 12 in order to make the light receiving surface of 2 stand vertically
Submount. At the same time, the drive IC 8 for controlling the LED 7 is die-bonded and wire-bonded.
Then, the distance dimension between the front surface of the transmission / reception device 15 and the end surface of the optical fiber 2 can be set as small as possible. Partition wall 16A formed between the two countersunk grooves
Forms a light shielding wall for preventing optical interference between both chips, which is a feature of the present embodiment.

In addition, as shown in FIGS. 2 to 4, a cover 21 made of a resin or a metal member is adhered to the upper surface of the base substrate 16 on which the light receiving / light emitting device is mounted by an adhesive agent or the like so that the bidirectional optical transmission device is formed. Make up fifteen. The bidirectional optical transmission device 15 has a dust-proof / moisture-proof function by sealing the optical transmission path 22 formed on the front surface of the cover 21 with a lens 23 made of a translucent material such as plastic or glass. Is to have. The optical transmission path 22 also serves as a positioning guide for the tip of the optical fiber 2. When the optical transmission path 22 is not sealed with the lens 23, the light receiving / light emitting element is coated or sealed with a translucent resin.

With the above-described structure, the partition wall formed by the two counterbore grooves formed on the substrate prevents optical interference between the light receiving and light emitting portions, and at the same time, each counterbore groove serves as an optical transmission path from the light emitting chip. The emitted light is efficiently guided by the optical transmission line and prevented from entering the light receiving chip by the partition wall. In addition, the through-hole electrode formed on the substrate can be surface-mounted to enable reflow. Furthermore, by forming a transmission / reception device in which the light emitting device and the light receiving device are integrated, a small-sized one-core bidirectional optical transmission device can be supported.

[0023]

As described above, the optical transmitter / receiver device is integrated, and at the same time, the partition wall can prevent optical interference and efficiently transmit the optical output. The surface mount type enables reflow, and is small and inexpensive. It is possible to provide a single-core bidirectional optical transmission device.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a one-core bidirectional optical transmission device according to an embodiment of the present invention.

FIG. 2 is a perspective view of the transmitting / receiving device of FIG. 1 seen through.

3 is a cross-sectional view of the transmission / reception device of FIG.

FIG. 4 is a cross-sectional view of the main parts of FIG.

FIG. 5 is a sectional view of an essential part showing the structure of a conventional two-core bidirectional optical transmission module.

6 is an explanatory view from the direction of arrow A in FIG.

[Explanation of symbols]

1A optical fiber plug 2 optical fiber 3A optical transmission module 4 housing 7 LED (or LD) 8 IC 12 IC (light receiving) 15 Transmitting / receiving device 16 base substrate 16A bulkhead 17 Through-hole electrode 18A, 18B counterbore groove 19 Plating coating 20 blocks (metal block or plastic) 21 cover 22 Optical transmission hole 23 Lens (glass or plastic)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuaki Kayonuma             Yamanashi Prefecture Fujiyoshida City Kamigure 1-23-1             Citizen Electronics Co., Ltd. F term (reference) 2H037 AA01 BA03 BA12 CA08 DA03                       DA04 DA06 DA15 DA31                 5F041 AA47 DA13 DA20 DA77 DA83                       EE04 EE24 FF14                 5F073 AB27 AB28 BA02 FA07 FA08                       FA30                 5F088 BB01 EA09 JA05 JA11 JA12                       JA14 JA20

Claims (5)

[Claims] 1. An optical minijack or an optical transmission module having a light-emitting chip and a light-receiving chip mounted and integrated in a single housing and provided with electrode terminals for electrical connection to the outside, and the optical minijack or optical. In a bidirectional optical transmission device in which an optical fiber plug is engaged with a transmission module, the optical minijack or the optical transmission module has one base substrate having a through-hole electrode which is an electrode terminal for electrical connection with the outside. To be mounted on the upper surface of the chip at a predetermined position between the two chips, which are arranged in parallel along the optical transmission direction.
Two grooved countersunk grooves are formed, a light emitting chip is mounted on the bottom surface of one of the countersunk grooves, and a light receiving chip is mounted on the bottom surface of the other countersunk groove to form an optical transmission path. A partition formed between the countersunk grooves has a function of a light shielding wall for preventing optical interference between both chips, and a single-core optical fiber plug is engaged with the optical minijack or the optical transmission module. Optical transmission device. 2. The bidirectional optical transmission device according to claim 1, wherein the surfaces of the two counterbore grooves formed on the base substrate are plated. 3. The bidirectional optical transmission device according to claim 1, wherein a block composed of a metal block or a plastic block is sub-mounted on the back surface of the light receiving chip. 4. The bidirectional optical transmission device according to claim 3, wherein the block is a heat dissipation / conductive member. 5. The bidirectional optical transmission device according to claim 1, wherein the optical transmission hole formed in the front surface of the case of the optical minijack or the optical transmission module is sealed with a lens made of glass or plastic. .