JPH07209556A - Optical transmission and reception module - Google Patents

Abstract

PURPOSE:To mount parallel transmitted light modules with high density and facilitate aligning operation by using a receptacle type optical fiber array which has array light emitting elements and array light receiving elements couple together with an optical fiber array or optical waveguide and does not has a ribbon of optical fibers. CONSTITUTION:The optical transmission and reception module which performs optical parallel transmission has an LD array (light emitting element) 12 and a PD array (light receiving element) 13 formed at specific positions and the optical fiber array 10 or light guide which is connected to both the array element altogether is constituted. The LD array 12 and PD array 13 are formed on parallel axes respectively and connected to an IC 14 for LDs and an IC 15 for PDs. The LD array 12 and PD array 13 are manufactured independently of each other and aligned with and positioned at an integrated optical fiber array 10 through an array lens 11 at need. Consequently, the mount density can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transceiver module for optical parallel transmission for transmitting optical signals to a plurality of lines at the same time.

[0002]

2. Description of the Related Art Conventionally, a parallel transmission optical module of a light emitting element and a light receiving element has been formed separately. An LD or an LED is used as a light emitting element, and a PD is used as a light receiving element independently of these, and light is collimated by an array lens as necessary to be incident on an optical fiber array.

[0003]

As described above, in the prior art, as shown in FIG. 6, the light emitter module (transmission module) and the light receiver module (reception module) are separately formed. In general, in order to transmit signals bidirectionally, it is necessary to mount a transmission module such as a device board and a reception module, which is an obstacle to high-density mounting.

FIG. 6 is a schematic diagram for explaining the structure of a conventional optical module. In addition, most of the cost of these modules is due to the work of aligning them with the optical fiber array and packaging costs, and the most important issue is to reduce the mounting cost of these modules in order to achieve low prices. Became.

[0005]

As a result of various studies on the above-mentioned problems, the present inventor has integrated an array light-emitting element and an array light-receiving element into an optical fiber array or an optical waveguide, and has no optical fiber tape. It was found that the use of a receptacle type optical fiber array facilitates high-density mounting and centering of parallel transmission optical modules.
The present invention has been completed.

That is, the present invention is: In an optical transceiver module for optical parallel transmission, an array of light emitting elements and an array of light receiving elements are formed at predetermined positions, and an optical fiber array or an optical waveguide that collectively connects both array elements. An optical transceiver module is provided. Further, the optical transmission line of the optical fiber or the optical waveguide in the optical fiber array or the optical waveguide is also characterized in that the array light emitting element and the array light receiving element are formed on the same axis or on the parallel axis, respectively. Have. Also,

The optical transmission line of the optical fiber or the optical waveguide formed on the parallel axis is also characterized in that it is two-dimensionally arranged. Further, the optical fiber array or the optical waveguide has a feature in that it has a light receiving / light emitting element coupling surface and an optical connector coupling surface, and has a coupling positioning guide with the optical connector. Another feature is that the light emitting elements and the light receiving elements are formed in a mixed manner and are formed into an array as a whole. It is also characterized in that the MFD at the tip of the optical fiber of the optical fiber array or the optical waveguide or the MFD at the tip of the optical connector coupled to the optical fiber array or the optical waveguide is converted corresponding to the coupling. Further, the optical fiber array or the optical waveguide is characterized in that a lens array is formed integrally with the transmission / reception type at the tip of the optical fiber array and is coupled to the light receiving / light emitting element via the lens array.

The present invention will be described below in detail with reference to the drawings. (I) Structure of Optical Transmitting / Receiving Module: FIG. 1 is a schematic diagram illustrating the basic configuration of the optical transmitting / receiving module of the present invention.
In FIG. 1, 10 is an optical fiber array, 11 is a lens array, 12 and 13 are LD arrays and PD arrays formed on parallel axes, and 14 and 15 are LD ICs connected to them. , PD IC. In addition, 10 may be formed by an optical waveguide. An optical fiber array will be described below as a representative.

As shown in FIG. 1, the LD array (light emitting element) and the PD array (light receiving element) are manufactured independently of each other, and are necessary for the integrated optical fiber array 10 when mounting (mounting). Accordingly, alignment and positioning are set via the array lens. In this case, the module is a transmission / reception integrated type, and the optical fiber array is also an integrated type.

Examples of this are LD-PD and LD-L
It also includes examples in which various optical elements such as D and LD-PD-LD are mixed. With such a configuration, as compared with the conventional method shown in FIG. 6, (i) downsizing of the module, (ii) shortening of mounting work, (iii) cost reduction of the optical fiber array (polishing) It is possible to improve the mounting density and reduce the mounting cost (such as mounting the optical fiber and the optical fiber all at once).

The optical fiber array according to the present invention is joined to the lens array, the LD array, the optical waveguide, etc., even if it is aligned and fixed with an adhesive or by welding with a solder or a YAG laser. Alternatively, a guide pin may be used. The optical fiber array of the present invention and the optical connector may be coupled with a guide pin, but may be coupled with a clip.

(II) Structure of Optical Fiber Array Constituting Module: FIG. 2 is a schematic view for explaining the basic configuration of the optical fiber array. In FIG. 2, an optical fiber V groove 2 is formed on a Si chip to form a lower plate 6,
The optical fibers 1 are arrayed and positioned with an accuracy of 1 μm or less. Further, a guide pin V groove 3 is formed in the lower plate 6, and the guide pin 4 is inserted into the guide pin V groove hole between the lower plate 6 and the upper plate to form an optical connector (not shown).
It is positioning with.

Metal flanges 9 (see FIG. 5) are provided on the outer peripheral sides of the upper and lower plates 5 and 6, and are fixed by soldering or YAG welding to the module. The module can be hermetically sealed by soldering part or all of the attachment of the optical fiber 1 to the optical fiber array section. Further, the end face of the optical fiber array is not limited to a flat end face, but may be obliquely angled by oblique polishing (for example, 5 to 10).
°) is also possible, and a non-reflective coating is also possible.

As a fixing material for fixing the optical fiber, an adhesive having high heat resistance, for example, an adhesive having a gas generation amount of 1% or less by weight when heated at 260 ° C. for 10 seconds, or a hermetic material such as solder or low melting glass. A seal member is preferred. The hermetic seal member is important for reliability management of the optical fiber array and the module.

As the solder material, solder suitable for joining optical fiber glass, ordinary Pb-Sn alloy, Zn,
Examples thereof include those to which additives such as Sb, Al, Ti, Si and Cu are added. In order to facilitate soldering to the optical fiber 1, it is preferable to apply a metal coat or a carbon coat to improve reliability.

Reference numeral 7 denotes an optical fiber pressing plate, which serves to press the optical fiber 1 into the optical fiber V groove 2 from a pressing member such as a clip (not shown) through the optical fiber pressing window 8. The guide pin V groove 3 may be separately processed from both ends of the optical fiber array.

The guide pin V groove 3 need not have any other positioning means, but may further have a push-pull type housing mechanism outside the optical fiber array. Metal flange 9 used in the present invention
The shape may be square or round, and the material of the metal flange is preferably amber or copearl alloy whose thermal expansion is relatively equal to that of the optical fiber array.

FIG. 3 is a schematic view showing the end face enlargement of the optical fiber array. In FIG. 3, the optical fibers 1 are arranged in 5 channels (5 cores) at a pitch of 250 μm, and LD and PD are made to correspond, and these 5 channel blocks are arranged linearly coaxially at a pitch of 12 mm. With such a configuration, LD and P based on the optical fiber array are used.
Can align and position the D array. Of course, if necessary, an array lens may be formed at the tip of the optical fiber array.

FIG. 4 shows an example of arrangement of the light receiving / light emitting elements (a).
It is a schematic diagram which shows (d). The present invention is not limited to the same straight line arrangement (a) shown in FIG. 4, and can be freely combined, for example, parallel straight line arrangement, two-dimensional arrangement, mixed arrangement, and the like. These may be designed in consideration of LD, PD productivity, and assemblability. In the above case, the optical element is L
Although description has been made using D and PD, it is of course applicable to an array of LEDs and other light emitting / receiving elements.

FIG. 5 is a schematic diagram for explaining a structural example of an optical fiber array corresponding to a two-dimensional array. It can also be applied to GI optical fibers. FIG. 7 is a schematic diagram illustrating an example of MFD enlargement conversion or MFD reduction conversion on the optical fiber array side and the optical connector side for coupling the optical fiber array.

As shown in FIG. 7, in the case of using the SM optical fiber, in order to facilitate coupling with the light emitting / receiving element,
The MFD of the optical fiber may be enlarged and converted [FIG. 7- (a)] (or reduced and converted: FIG. 7- (b)). Further, the MFD at the tip of the optical connector coupled to the optical fiber array may be enlarged (or reduced). In such a case, the optical connector and the optical fiber array have a small loss change with respect to the axis shift, and as a result, low loss coupling can be achieved, and it is desirable from the viewpoint of attachment / detachment stability.

[0022]

The present invention will be described in detail with reference to the following examples, which do not limit the scope of the present invention. A 10-ch LD array and a 10-ch PD array were coupled to a 20-ch single mode optical fiber array through a lens array to perform alignment. The MFD of the optical fibers in the optical fiber array is formed to be about 30 μm, and is designed so that the XY tolerance of alignment is increased.

A low thermal expansion alloy housing (metal flange) of amber or kovar alloy or the like was formed on the outer circumference of the optical fiber array, and hermetically joined to the module housing. Φ0.7 for optical fiber array
A groove corresponding to the guide pin of mm was machined, the guide pin was fixed here, and this portion was also hermetically sealed in the same manner. On the other hand, an external multi-core optical connector is formed inside the push-pull housing so that it can be connected to the transceiver module with one touch.

The MFD of a normal single-mode optical fiber is about 9.5 μm. Therefore, an MFD converter as shown in FIG. A multi-fiber optical connector converted to 0.5 μm was created. The conversion of the MFD was realized by fusion splicing the residual stress relaxation type optical fiber.

The resulting transceiver module has a coupling loss,
The transmission characteristics showed no problem, and it was more than double the mounting density on the printed circuit board. Although all of the optical fiber arrays have been described above, it is possible to form the optical fiber array with, for example, a quartz optical waveguide.

[0026]

As described above, according to the present invention, (i)
By packaging the LD array and PD array in one package, the density of mounting on the printed board was improved. (Ii) Conventionally, two sets of package housings and optical fiber arrays were required, but only one set is required, and mounting work can be performed at one time, which enables cost reduction. (Iii) MF of optical fiber array or multi-fiber optical connector
By converting D, the tolerance of alignment and the optical connector coupling is increased, and it is possible to improve the aligning workability and stabilize the optical connector coupling loss.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating a basic configuration of an optical transceiver module.

FIG. 2 is a schematic diagram illustrating a basic configuration diagram of an optical fiber array.

FIG. 3 is a schematic diagram showing an end face enlargement of an optical fiber array.

FIG. 4 is a schematic diagram showing array examples (a) to (d) of light receiving / light emitting elements.

FIG. 5 is a schematic diagram illustrating a structural example of an optical fiber array corresponding to a two-dimensional array.

FIG. 6 is a schematic diagram illustrating a configuration of a conventional optical module.

FIG. 7 is a schematic diagram illustrating an example of MFD enlargement conversion or MFD reduction conversion for the optical fiber array side and the optical connector side for coupling the optical fiber array.

[Explanation of symbols]

 1 optical fiber 1'two-dimensional array optical fiber 2 optical fiber V groove 3 guide pin V groove 3'guide pin V groove hole 4 guide pin 4'adjustment guide pin 5 upper plate 6 lower plate 7 optical fiber pressure plate 8 light Fiber holding window 9 Metal flange 10 Optical fiber array 10 'Optical fiber array with optical fiber tape 11 Array lens 12 LD array 13 PD array 14 LD IC 15 PD IC 16 Optical fiber tape 17 Optical connector

Claims (7)

[Claims] 1. An optical transmission / reception module for optical parallel transmission, wherein an array light emitting element and an array light receiving element are formed at predetermined positions, and an optical fiber array or an optical waveguide is formed to collectively couple with both array elements. An optical transmitter / receiver module characterized by being installed. 2. The optical transmission line of the optical fiber or the optical waveguide in the optical fiber array or the optical waveguide is formed on the same axis or on the parallel axis for the array light emitting element and the array light receiving element, respectively. The optical transceiver module according to claim 1, characterized in that 3. The optical transceiver module according to claim 2, wherein the optical transmission lines of the optical fibers or optical waveguides formed on the parallel axis are two-dimensionally arranged. 4. The optical fiber array or the optical waveguide receives light.
The optical transceiver module according to any one of claims 1 to 3, further comprising a light emitting element coupling surface and an optical connector coupling surface, and a coupling positioning guide for coupling with the optical connector. 5. The optical transmitter / receiver module according to claim 1, wherein the light emitting element and the light receiving element are formed in a mixed manner and are arrayed as a whole. 6. The MFD at the tip of the optical fiber of the optical fiber array or the optical waveguide or the MFD at the tip of the optical connector coupled to the optical fiber array or the optical waveguide is converted corresponding to the coupling. , Claims 1-5
The optical transceiver module according to any one of 1. 7. A transmission / reception integrated lens array is formed at the tip of the optical fiber array or the optical waveguide, and the lens array is coupled to the light receiving / light emitting element via the lens array. 7. The optical transceiver module according to any one of 6 to 6.