JPS60191212A - Optical circuit device - Google Patents

Abstract

PURPOSE:To obtain a stable, low-power consumption, and small-capacity optical circuit device by arranging an optical circuit substrate having an optical waveguide and a semiconductor laser connected to the optical waveguide on a holding member having a low heat conductibility and a holding member having a high heat conductibility, which form a holding base body, respectively and short- circuiting thermally the latter holding member to a casing. CONSTITUTION:An optical circuit substrate 12 having an optical waveguide 11 is arranged on the first holding member of a holding base body 33 provided with the first holding member 31 consisting of low-heat conduction materials and the second holding member 32 consisting of high-heat conduction materials, and a semiconductor laser 13 coupled optically to the optical waveguide 11 is arranged on the second holding member 32, and the second holding member 32 is short- circuited thermally to a part of a casing 15. Heat of the semiconductor laser is radiated through the casing, and the optical circuit substrate 12 is insulated thermally from the casing 15 used as a radiating plate, and thus, stable characteristics are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to optical circuit devices. In particular, it relates to an optical circuit device that integrates a semiconductor laser and an optical integrated circuit.

Conventional Structure and Problems Conventionally, a device integrated with a semiconductor laser and a seven-light integrated circuit has been considered to have the structure shown in FIG. That is,
A semiconductor laser 13 optically coupled to an optical waveguide 12 on an optical circuit board 11 is fixed on the same substrate 14, and a housing 16 is filled with nitrogen to prevent oxidation deterioration of the light emitting end face of the semiconductor laser.
The configuration was maintained as follows. Since a semiconductor laser generates heat when excited with laser light, the excitation wavelength changes. Therefore, the semiconductor laser 13 radiates heat in the housing 15 via the base 14. However, heat dissipation from the semiconductor laser 13 causes non-uniform thermal expansion of the base 14, resulting in problems such as a decrease in optical coupling and a change in the characteristics of the optical waveguide 11.

In addition, especially when using a high-output semiconductor laser, the second
The composition of the diagram was considered. 11+12.13,14 in the same figure
．． 15 is the same as in FIG. That is, the configuration is such that the cooling surface of the semiconductor cooling element 21 is attached to the casing 16, and the heat sink 22 is attached to the heat generating surface. In this configuration, the housing 1
Since the semiconductor laser 5 itself is cooled, not only the semiconductor laser 13 but also the base 14 are cooled. Therefore, non-uniformity in thermal expansion of the base body 14 was small, optical coupling efficiency was high, and characteristics of the optical waveguide were stable. However, in order to cool the entire housing 16, the operating current of the semiconductor cooling element 21 is also required to be at least 100 amperes, and the heat sink 22 is also required to have a large area. It is difficult to reduce power consumption and size of the device, which greatly limits the applications of optical circuit devices. In addition, the structure shown in FIG. 2 is possible even in the case of a low-power semiconductor laser.

However, it is also necessary to cool the entire housing 15, which poses a problem in reducing power consumption and downsizing the device. It can be made small and lightweight with low power consumption, and has stable characteristics.

Purpose of the Invention The purpose of the present invention is to improve the instability of conventional characteristics, high power consumption, and large volume, and to create a low power consumption and large volume with stable characteristics.
This provides a small volume optical circuit device.

Structure of the Invention The present invention provides a holding base having a first holding part made of a low heat conductive material and a second holding part made of a high heat conductive material.
An optical circuit board having an optical waveguide is installed in the first holding part, a semiconductor laser is arranged in the second holding part to be optically coupled to the optical waveguide, and the second holding part is heated to a part of the housing. It has a short-circuited structure.

In particular, a structure is adopted in which a semiconductor cooling element is provided with a thermal short circuit in the second holding part, and the semiconductor cooling element is thermally short-circuited to a part of the casing, and the semiconductor cooling element is used for i-degree control. Is going.

Description of examples The present invention will be explained based on the embodiment shown in FIG.

In between, 11, 12, 13 and 14, 15 are the same as in FIG. In the structure according to the present invention, in a holding base 33 having a first holding part 31 made of a low heat conductive material and a second holding part 32 made of a high heat conductive material, the first holding part 31
An optical circuit board 12 having an optical waveguide 11 is installed on the second
A semiconductor laser 13 is arranged in the holding part 32 to be optically coupled to the optical waveguide 11, and the second holding part 32 is thermally short-circuited to a part of the casing 15.

In the above configuration according to the present invention, the semiconductor laser 13
When the output was 1 mW or less, the heat generated by the semiconductor laser 13 was sufficiently generated by the casing 16, and there was no problem with the deviation of the excitation wavelength. However, the optical coupling between the optical waveguide 11 and the semiconductor laser 13 was stable, and changes in the characteristics of the leading waveguide did not cause any problems. This is considered to be because, unlike the conventional configuration, the casing 15 used as a heat sink and the optical circuit board 12 are thermally insulated, so that the change in thermal expansion is reduced. Furthermore, although the details are unknown, it is believed that the first holding part 31 is less bent due to thermal expansion due to the temperature difference between the optical circuit board 12 side and the housing 16 side, thereby preventing a decrease in optical coupling efficiency. Therefore, it was confirmed that the same effect could be obtained even if the present configuration was changed as shown in FIG. In the same figure, 11.12. '13,1'5,31
．． It is the same as Figure 3 for ores 32 and 33. That is, the same effect was obtained when the gap 41 was provided between the first holding part 31 and the housing 15 to further ensure thermal insulation.

Furthermore, in order to stabilize the optical circuit device, it is preferable to use a semiconductor cooling element as explained in the conventional example. However, the conventional example was insufficient in terms of energy saving, but the present inventors improved the arrangement of the semiconductor cooling element to the above configuration and invented a new optical circuit device with low power consumption and excellent characteristics. did. That is, the explanation will be based on the embodiment shown in FIG. In the same figure, 11.12, 13, 15, 31.32
33 is the same as in FIG. In the figure, a semiconductor cooling element 61 is provided by being thermally short-circuited to the second holding part 32, and further, the semiconductor cooling element 51 is thermally short-circuited to a part of the casing 16. In this configuration of the present invention, which is completely different from the conventional example, the semiconductor cooling element 51 is used for cooling.
It is only the holding part 32. Moreover, since only the second holding part 32 was cooled, stable optical characteristics were obtained by using only the housing 15 as a heat sink. For example, wavelength 0
．． A semiconductor laser of 83 μm and an output of 25 mW was used, a sapphire substrate was used as the optical circuit board 12, and a PLZ
A total reflection type optical switch consisting of a T-thin film optical waveguide was constructed. The first holding part 31 is made of stainless steel, which is a low thermal conductive material (
1a/s) (0,151J7hrS-K) using
The second holding part 32 is made of copper (417cm-
A 7/l/mini ram (2,4, I/car S-K) is used in the housing 15, and the interior of the housing is filled with zero nitrogen to prevent deterioration of the emission end face of the semiconductor laser 13. We prototyped a circuit device. A constant temperature control of, for example, 25° C. was possible with a current capacity of about 1 A in the semiconductor cooling element 61, and there was no change in the excitation wavelength of the semiconductor laser 13, which was good. This enables much lower power consumption and miniaturization than conventional cooling, which requires about 5 A and also requires a separate heat sink. Furthermore, since the semiconductor element 13 is housed within the housing 15, a decrease in cooling efficiency due to non-uniform temperature distribution of the semiconductor element 13 itself due to outside air convection is also prevented, making such high efficiency possible. It was also confirmed that there was little change in the optical coupling efficiency, and that the characteristics of the total reflection type optical switch were such that a driving voltage of 5 V and an extinction ratio of 15 dB were stably obtained.

As is clear from the relationship between the embodiment shown in FIG. 3 and the second embodiment shown in FIG. 4, the third embodiment shown in FIG. Examples were also possible. 6th
Circles in the figure are 11' and 12.

13.15, 31.32, 33, and 51 are the same as in FIG. That is, it has been confirmed that even if the gap 61 is used between the first holding part 31 and the housing 61 to ensure thermal insulation, the same effect as in the third embodiment can be obtained.

The shape of the second holding part according to the present invention may be made of a highly thermally conductive material that can fix the semiconductor laser.
The structure shown in the figure is also possible and is included in the present invention. Go to the same figure, 11° 12.13, 15, 31.3
2,33.51 is the same as in FIG. Second holding part 32
Similar effects were obtained even when the structure was made smaller by making the structure U-shaped and providing a drive section for the semiconductor laser 13 inside the U-shape. As is clear from the following explanation, the 9g2 holding portion 32 can be formed in a U-shape or in any other shape.

In the above explanation, the optical circuit board was directly provided on the first holding part, but in the structure according to the present invention, if the optical circuit board is fixed to the first holding part made of a low thermal conductive material, The effects included in the present invention are realized. For example, the configuration shown in FIG. 8 is also naturally included in the present invention.

In the same figure, 11, 12, 13, 15, 31.

32.33.51 are the same as in FIG. That is, the same effect was obtained with the configuration in which the tapered support body 81 was inserted between the optical circuit board 12 and the second holding portion 31 in the same figure. It is clear that the use of the tapered support 81 facilitates optical coupling between the semiconductor laser 13 and the optical waveguide 11.

All of the embodiments described above are examples in which a semiconductor laser and an optical circuit board are combined as an optical transmission path within the housing.

However, the effect of the present invention is that the optical characteristics of the optical circuit board and the semiconductor laser are stabilized, and the effect is the same even if an optical fiber is optically coupled to the optical waveguide, which is included in the present invention. It is. That is, an example thereof is shown in FIG. 9. In the same figure, 11°12.13,15,31.
32.33 are the same as in FIG. By optically coupling the optical fiber 91 to the output end of the optical waveguide 11 and taking the other end of the optical fiber 91 out of the housing, for example,
When using a total reflection type optical switch made of LZT thin film,
A modulated light source with an ON-OFF digital optical output was constructed. In this case as well, it was confirmed that the characteristics of a driving voltage of 5 V and an extinction ratio of 1 sdB could be stably obtained.

In all of the above embodiments, the semiconductor laser and the optical waveguide were optically coupled by end-face excitation. However, the effects of the present invention are the same regardless of the difference in optical coupling method.

Therefore, similar effects were obtained even when an optical lens was inserted between the semiconductor laser and the guide waveguide for optical coupling. In addition, the same applies to a method called taper coupling.

Effects of the Invention As is clear from the above explanation, the present invention provides an optical circuit device configuration that is small, low-power, and has stable optical characteristics, greatly expands the field of application of the optical circuit device, and has high practical value. It is something.

[Brief explanation of the drawing]

Figures 1 and 2 are cross-sectional views of main parts of conventional optical circuit devices.
FIG. 3 is a cross-sectional view of a main part of an optical circuit device according to an embodiment of the present invention, FIG. 4 is a cross-sectional view of a main part of an optical circuit device according to a second embodiment of the present invention, and FIG. 6 is a cross-sectional view of a main part of an optical circuit device according to a fourth embodiment of the present invention, and FIG. 7 is a cross-sectional view of a main part of a device according to a fifth embodiment of the present invention. 8(a) and 8(b) are a sectional view and a side sectional view of a main part of a device according to a sixth embodiment of the present invention, respectively, and FIG. 9 is a sectional view of a main part of a device according to a seventh embodiment of the present invention. FIG. 2 is a sectional view of a main part of the device. 11... Optical waveguide, 12... Optical circuit board, 13... Semiconductor laser, 15...
Housing, 31... First holding part, 32...
Second holding part, 33... Holding base f 41...
...Gap, 61...Semiconductor cooling element, 61...
...Gap, 81... Taper support, 91.
...Optical fiber. Figure 1 I Figure 3 1 3 Figure 4 1 Figure 5 3 3 Figure 6 3

Claims (2)

[Claims] (1) An optical circuit board having an optical waveguide in the first holding part is installed on a holding base having a first holding part made of a low thermal conductive material and a second holding part made of a high thermal conductive material, and the second holding part An optical circuit device, characterized in that a semiconductor laser is arranged to be optically coupled to the optical waveguide, and the second holding part is thermally short-circuited to a part of the casing. (2) A semiconductor cooling element is thermally short-circuited to the second holding part, and the semiconductor cooling element is thermally short-circuited to a part of the casing. Optical circuit device described in section.