JPS6258211A - Photocoupler - Google Patents

Abstract

PURPOSE:To make disassemblage of a photocoupler possible to as to reutilize an optical element, by constituting the photocoupler of the 1st base which holds one optical element to be optically coupled with another optical element, 2nd base which is fixed to the 1st base under a removable condition, and the another optical element held by the 2nd base. CONSTITUTION:The 2nd base 16 is newly fixed to an LD stem (1st base) 7, to which an LD 1 is fixed, by means of screws 17 and a holder 10 is fixed to the 2nd base 16 by soldering 8. Therefore, when any trouble occurs in the assemblage of this LD module, the 2nd base 16 can be separated from the LD stem 7 by loosening the screws 17 and the expensive LD 1, 1st lens 2, and an LD package in which a holder 9 is enclosed can be reutilized.

Description

[Detailed Description of the Invention] (Technical Field) The present invention allows optical elements such as 4' conductor lasers, isolators, lenses, etc. to be aligned with high precision while maintaining optical coupling, and to be assembled and fixed with a high yield. This invention relates to an optical coupling device.

(Prior art) In the optical fiber transmission system, it is important to align the light source, lens system, optical fiber, etc. with high precision and to assemble and fix them at a high yield in order to reduce the cost of the optical coupling device. Guaru.

In the case of an LD module that uses a semiconductor laser (LD) as a light source and a single mode optical fiber (SMF) as an optical fiber, an optical coupling lens system is used.
The confocal compound lens system shown in the figure (Saruwatari et al., IE E
E J OLJ r na I of Q
u a'ntum Electron, vol, QE
-17, pp, 1021-1027. June 19
81), second lens segmented confocal compound lens system (Kono et al.: IEEE Journal of Light
wave Technol, vol, LT-3, Au
a, scheduled to be published in 1985), pseudo-confocal compound lens system (A
DE)1. opt, VO1, 24, pp, 984-98
9. Apr, 1985) etc. have been proposed.

In FIG. 2, the beam emitted from L D 1 is converted into almost parallel light by the second lens 2, and enters the SMF 4 by the second lens 3. Figure 3 shows the second lens 3
- It has a configuration divided into a lens and a 2nd-2nd lens,
A second lens 5 causes the parallel light to enter a second lens 6 integrated with the SMF 4. In FIG. 4, the lens 2 narrows down the beam a little and avoids the I beam from entering the 2-2 lens 6, which is integrated with the SMF 4.

In the lens system shown in Figures 3 and 4, the fiber section (SMF4 and
-2 lens 6)) is more relaxed than in the case of one SMF71B body.

In these lens systems, the tolerance for axis misalignment of the optical system components (lens, fiber, or fiber section) is determined by the tip of the taber (Kuwabara et al., App+, opt, vol. 19.
It is much looser than microlens systems such as pp, 2578-2583°1980>. However, it is difficult to assemble LD modules with a yield of 100%. The cause of this will be explained below.

(Problems to be Solved by the Invention) FIG. 5 shows a configuration diagram of an LD module manufactured by soldering and fixing using a confocal compound lens system with a split second lens. 7 in the figure is an LD with l-01 fixed.
A holder 9, which is a stem (first base) and further has the first lune 2 fixed thereto, is fixed to the LD stem 7 by a half 1f18. The holder 10 to which the second lune 5 is fixed is also L
It is fixed to the D stem 7 with a half fl18. 2-2
The core 11 to which the lens 6 and the SMF 4 are fixed is fixed to the holder 12 for integration using a technique 18, and the holder 12 for integration is further fixed to the holder 10 of the lens 2-1 via the holder 13 with solder 8. has been done.

A high-frequency induction heating device is generally used for fixing the solder, but if the mutual positional relationship between the induction coil, the solder, and the holder deviates from the optimal state, the heating of the half 111 and the holder will not be sufficient, and the wettability of the half 11 will be reduced. As a result, a highly reliable LD module that can be put to practical use cannot be realized. Also, in this case, since half of the holder 10 of the second lunse 5 is fixed to the LD stem 7, the LD stem 7 etc. to which the holder 9 of the LD1 and the second lunse are fixed cannot be reused, and the LD stem 7 is fixed to the LD stem 7.
A disadvantage is that if the yield of the module is poor, the price becomes significantly high. Furthermore, the above-mentioned drawbacks also exist when laser welding or adhesives are used as the fixing method. In addition,
Since the tolerance for the axis misalignment of the second lun is large, the fixation of the holder 9 of the second lun to the LD Sdem 7 is almost 100%.
It has been confirmed that it can be done with a yield of . Further, the holder 9 to which the LDl and the second lunz are fixed is fixed to the LD stem 7, and then filled with N2 gas and hermetically sealed with a package 15 with a glass window 14 (hereinafter referred to as
These are called LD packages).

(Object of the Invention) The object of the present invention is to solve the conventional problem that if 1-0 module assembly fails, expensive LDs cannot be reused and the price of the LD module becomes high. l
- Yield 10 for about 1 after forming the package
The purpose is to provide 11 structures of optical coupling devices that can manufacture LD modules at 0% production.

(Means for Solving the Problems) In order to solve the problems mentioned above, the present invention provides a first base that holds one optical element to be optically coupled, and a detachable device that can be attached to the first base. a second base movably fixed;
The optical element is held via a base of the optical element and the other optical element to be combined with the optical element.

(Function) According to the present invention, if any problem occurs in assembling the optical coupling device, the second base can be removed from the first base and the optical coupling device can be disassembled, and the optical element can be reused. can.

(Embodiment) FIG. 1 is a diagram for explaining one embodiment of the present invention,
Components that are the same as those of the conventional example are denoted by the same reference numerals. That is, 1 is the LD, 2 is the second lun, 3 is the second lens, 4 is the SMF, 5 is the second lun, 6 is the second-second lens, 7 is the ID stem, 8 is the solder, and 9 is the second lun. holder, 10
11 is a holder for the second lune 5, 11 is an opening, 12 is an integration holder, 13 is a holder for fixing the integration holder 12, 14 is a window, and 15 is a hermetic package.

In this example as well, I fixed Iro and 01, and U') Stem 7
A second base 16 is newly fixed to the first base (the first base) with screws 17, and the holder 10 is fixed to the second base 16 with a half 018.The other configuration is shown in FIG. This is the same as the conventional example shown. Further, the assembly after fixing the second base 16 to the first base 7 with the screws 17 can be performed in exactly the same manner as in the case of the conventional LD module shown in FIG.

Since it is configured as described above, if any problem occurs in assembling the LD module, the LD stem 7 to which the lens holder 9 is fixed can be separated from the base 16 by loosening the screw 17 shown in the figure. , the ID package containing the inexpensive Dl, the second runz 2, and the holder 9 can be reused. Therefore, the yield is 100 for +-n packages.
%, which is effective in reducing the price of the LD module. This improvement effect becomes even more remarkable when the present invention uses an extremely expensive FB or the like as LD1. L f) Package window 14 and second lens 5
In addition to the case where a spherical focusing rod lens is used in place of the second lens 2 in FIG. When using a glass plate with an IF film (AR), or using its spherical converging rod lens and AR cocoon.
The present invention can be easily applied to cases where an isolator is inserted between plates, or to optical coupling devices using other optical elements.

Further, after assembling the 1-D seven wheels, the LD stem 7 and the base 16 may be fixed by laser welding or the like to reinforce the temporary fixation by the screws 17. Note that instead of using the screws 17, temporary fixation may be performed using an adhesive.

The 1-n module may be configured such that it is fixed to the first base and only the semiconductor laser is enclosed in an inert gas.

The embodiments of the present invention have been described above as an optical coupler that couples light emitted from a semiconductor laser, which is a light emitting element, to an optical fiber, but conversely, it can also be used as an optical coupler that couples output light from an optical fiber to a light receiving element. It goes without saying that the structure of the optical coupler of the present invention is also effective.

(Effects of the Invention) As explained above, according to the present invention, a first base holding one optical element to be optically coupled;
The second base is removably fixed to the base of Even if some trouble occurs, the base on which the hexavalent optical element is fixed can be easily separated from the rest of the optical system, and the expensive optical element can be reused. This combination has the advantage that a yield of 100% can be achieved for this optical element, and the cost of the optical coupling device can be significantly reduced. Further, after assembling the optical coupling device, if the two bases fixed with screws or the like are reinforced and fixed by laser welding or the like, a highly reliable optical coupling device can be realized.

[Brief explanation of the drawing]

Fig. 1 is a partially vertical side view of an optical coupling device showing an embodiment of the present invention, and Fig. 2.3.4 is a side view of an optical coupling device showing an embodiment of the present invention.
An explanatory diagram of the lens system of the module, FIG. 5 is a conventional configuration diagram of an LO 7 lens system using a second lens split type confocal compound lens system. 1... LD, 2... 2nd lens, 3... 2nd lens, 4... SMF15... 2nd-lens, 6... 2nd-2nd lens, 7... LD stem (first base),
8...Solder, 9...Luns holder, 10...
2nd lunes holder, 11... Sheet, 12... Holder for integration, 13... Holder for fixing and covering the holder for integration, 14... Window, 15... Hermetic package. , 16...Second base for assembling an optical system other than the ID package

Claims (2)

[Claims] (1) A first base holding one optical element to be optically coupled, a second base removably fixed to the first base, and the second base held through,
An optical coupling device comprising the optical element and another optical element to be coupled. (2) The first base has a semiconductor laser fixed to the base, and a hermetic package with an output window that covers the semiconductor laser and is hermetically sealed to the first base, and inside the hermetic package. 2. The optical coupling device according to claim 1, wherein an inert gas is sealed in the optical coupling device.