JP2003315606A - Waveguide type optical module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waveguide type optical module which has a low power consumption and is low in cost. <P>SOLUTION: The heat of a sheet heater 3 is confined by an optical waveguide 1, a gel-state silicone adhesive 10, and positioning members 4 and 5, so the heat can efficiently be conducted to the optical waveguide 1. Further, the module is of simple constitution such that the optical waveguide 1 is fixed with the gel-state silicone adhesive 10, so there is no influence of external forces of vibration, a shock, etc., and the cost is reducible. Further, there is not stress caused before by a setting shrinkage of an adhesive. Further, no heterogeneous material is used, so stress due to thermal strain of a package exerts no influence on optical characteristics of the optical waveguide 1. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveguide type optical module.

[0002]

2. Description of the Related Art With the development of WDM transmission technology, optical device products using optical waveguides are being rapidly put into practical use.
The optical waveguide is an optical circuit obtained by depositing a quartz core, which is an optical signal transmission line, on a quartz or silicon substrate.
The refractive index changes with changes in temperature and physical stress exerted on the core, and the optical characteristics change. Therefore, such an optical waveguide is always housed in a module having a function of adjusting the temperature within a certain temperature range. Further, the structure for accommodating the optical waveguide must be such that no stress is exerted on the optical waveguide or the change in thermal stress is small. As a method of maintaining the optical waveguide at a constant temperature, there is a method of incorporating a heater or a Peltier element in the module to adjust the temperature.

[0003]

By the way, in recent years, while the demand for low power consumption is increasing, the power required for temperature control is set to about 2 to 6 W. In this case, how to efficiently heat and hold the optical waveguide is a technical subject, and researches are being actively conducted at present. Up to now, the package of the optical module has a double structure to keep the heat dissipation of the optical waveguide low, or the package wall is doubled and the atmosphere inside the wall is filled with a gas with a low thermal conductivity to release the optical waveguide. It is reported that the amount of heat is kept low.

However, the above-mentioned conventional techniques have the problems of high power consumption and high cost.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a waveguide type optical module with low power consumption and low cost.

[0006]

In order to achieve the above object, the invention of claim 1 is a waveguide type optical module in which the temperature is adjusted by a heater so that the optical waveguide is within a predetermined temperature range. Attach a planar heater to the optical waveguide,
A gel-like member is filled in the recess of the lower positioning member, at least one of the optical waveguide and the planar heater is immersed in the gel-like member, and the lower positioning member is covered with the upper positioning member.

According to the invention of claim 2, in addition to the structure of claim 1, it is preferable that the upper positioning member and the lower positioning member are made of a resin such as calcium silicate, hard urethane or phenol foam.

According to the present invention, since the heat of the planar heater is confined in the upper positioning member and the lower positioning member by the optical waveguide and the gel-like member, the heat of the planar heater can be efficiently supplied to the optical waveguide. it can. In addition, since the optical waveguide is fixed with a flexible gel-like member, there is no effect of external force such as vibration and shock, cost reduction can be achieved, and it can be fixed with an adhesive as in the past. In comparison, there is no stress due to curing shrinkage. Further, since no different materials as in the conventional case are used, stress due to thermal strain of the package does not affect the optical characteristics of the optical waveguide.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a diffusion exploded perspective view of a waveguide type optical module of the present invention.

In the present waveguide module, the planar heater 3 is attached to the optical waveguide 1, and the concave portion 4a of the lower positioning member 4 is filled with the silicone adhesive 10 as a gel-like member.
At least one of the optical waveguide 1 and the planar heater 3 is dipped in the gel silicone adhesive 10 and the lower positioning member 4 is covered with the upper positioning member 5, so that the optical waveguide 1 is within a predetermined temperature range (60 The temperature is controlled so that the temperature becomes 80 ° C).

A temperature sensor 2 is fixed to the optical waveguide 1,
It is connected to a control device (not shown). The lower positioning member 4 is housed in the base component 6, and the upper positioning member 4
Are covered with a cover part 7.

The present waveguide type optical module includes a planar heater 3
Since the heat of the sheet is confined by the optical waveguide 1, the gel-like silicone adhesive 10 and the positioning members 4 and 5, the planar heater 3
The heat can be efficiently supplied to the optical waveguide 1. The temperature inside the positioning members 4 and 5 is detected by the temperature sensor 2,
A control device (not shown) controls so that necessary electric power is supplied to the planar heater 3. For this reason,
The temperature of the optical waveguide 1 is controlled within a predetermined temperature range.

Further, since the optical waveguide 1 is fixed by the gel-like silicone adhesive 10 having flexibility, the gel-like silicone adhesive 10 is not affected by external force such as vibration and impact, and stress is generated due to curing shrinkage of the gel-like silicone adhesive 10. Absent. Furthermore, unlike the prior art, since different materials are not used, stress due to thermal strain of the package does not affect the optical characteristics of the optical waveguide 1. In the figure, 8 is an optical fiber, and 9 is an optical fiber array.

[0015]

EXAMPLE 1 FIG. 2 is a perspective view showing an example of a waveguide type optical module of the present invention.

The optical waveguide 1 is connected to an optical fiber array 9 formed by arranging optical fibers 8 in a line with optical axis alignment,
A temperature sensor (not shown) is fixed on the front surface, and the planar heater 3 is bonded and fixed on the rear surface.

The temperature sensor is an RTD (platinum side temperature resistor), and the sheet heater 3 is a silicon rubber heater or AIN.
Ceramic heaters such as (aluminum nitride) heaters.

The lower positioning member 4 has a recess 4a having a size such that it does not come into contact with the optical waveguide 1, the fiber array 9 and the planar heater 3, and the optical fiber 8 is taken out at the edge. A step portion is formed. By filling the gel-like silicone adhesive 10 in the recess 4a, the gel-like silicone adhesive 10 is pooled.

Here, the gel-like silicone adhesive 10 is
It means a low elasticity silicone material.

The optical waveguide 1 has an optical axis with the optical fiber 8 when the silicone adhesive 10 is cured (has some flexibility even when cured) in a state of floating on the gel silicone adhesive 10. Is held in a straight line. The positioning members 4 and 5 are low heat conductive members such as foamable plastics having a function as a heat insulating member, and are materials that liquid does not penetrate.

In this case, the heat of the planar heater 3 is applied to the optical waveguide 1, the gel-like silicone adhesive 10, the positioning member 4,
Since most of the light is confined within 5, the heat can be efficiently supplied to the optical waveguide 1.

Further, since the silicone adhesive 10 for fixing the optical waveguide 1 is gel-like and is very flexible,
External force such as stress, vibration and impact due to curing shrinkage of the adhesive,
The stress due to the thermal strain of the package due to the use of different materials has little influence on the optical characteristics of the optical waveguide.

(Embodiment 2) FIG. 3 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

In this waveguide type optical module, only the planar heater 3 is immersed in the gel silicone adhesive 10, and the optical waveguide 1 is in contact with only the positioning member 4. In this waveguide type optical module, the positioning work of the optical waveguide 1 can be performed more easily than in the case of the first embodiment.

However, the positioning member 4 by the external force
Deformation or the like may be directly transmitted to the optical waveguide 1 and affect the optical characteristics. In addition, it is necessary to fully consider the type of the optical waveguide 1 and the thermal and mechanical characteristics of the positioning members 4, 5.

Therefore, this waveguide type optical module can achieve the same effects as those of the first embodiment on the assumption that the design is made in consideration of thermal and mechanical characteristics.

(Embodiment 3) FIG. 4 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

In this waveguide type optical module, the volume of the concave portion 4a of the lower positioning member 4 is smaller than that in the second embodiment, and only the back surface of the planar heater 3 comes into contact with the gel-like silicone adhesive 10 and the planar shape is obtained. The heater 3 has a structure in which parts of both sides of the heater 3 come into contact with the positioning member 4.

This waveguide type optical module has a smaller bonding area with the gel-like silicone adhesive 10 than in the case of the second embodiment. However, when the ceramic heater is used, the highly rigid sheet heater 3 receives an external force, and therefore the influence of the external force on the optical characteristics of the optical waveguide 1 is smaller than that in the second embodiment.

Therefore, this waveguide type optical module can achieve the same effect as that of the first embodiment on the assumption that the design is made in consideration of thermal and mechanical characteristics.

(Embodiment 4) FIG. 5 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

In this waveguide type optical module, the planar heater 3 is attached to the surface (core side) of the optical waveguide 1, and only the optical waveguide 1 is brought into contact with the gel silicone adhesive 10. That is, the positions of the optical waveguide 1 and the planar heater 3 shown in Example 1 are reversed.

In this waveguide type optical module, the heat from the planar heater 3 passes through the core and the gel-like silicone adhesive 1
It is becoming conductive to zero. Although the thermal efficiency is better than that of the first embodiment, since the planar heater 3 is directly attached to the core, it is necessary to carefully select the adhesive for fixing the planar heater 3 so as not to adversely affect the core. .

Therefore, in this waveguide type optical module, the same effect as that of the first embodiment can be obtained on the assumption that the adhesive is carefully selected.

(Embodiment 5) FIG. 6 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

In this waveguide type optical module, the volume of the concave portion 4a of the positioning member 4 is made smaller than that of the fourth embodiment, and only the back surface of the optical waveguide 1 is covered with the gel-like silicone adhesive 10.
To the positioning member 4 by contacting part of both sides of the optical waveguide 1.
It has a structure in contact with.

Also in this waveguide type optical module, the same effect as that of the first embodiment can be obtained.

(Embodiment 6) FIG. 7 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

This waveguide type optical module has a structure in which the size of the planar heater 3 is larger than that of the optical waveguide 1 and only the optical waveguide 1 is immersed in the recess 4a.

Although the thermal efficiency is slightly lower than that of the fifth embodiment, when the ceramic heater is used, the positioning is easy and the influence of the external force on the optical characteristics of the optical waveguide 1 is smaller than that of the fifth embodiment.

In the above, according to the present invention, (1) a waveguide type optical module in which the temperature of the optical waveguide is adjusted within the temperature range of 60 to 80 ° C. A base member that forms the outer shape, a cover member, and a positioning member that is fixed with a silicone adhesive inside each are arranged, and
The lower positioning member has an area wider than the area including the optical waveguide element in which the planar heater and the temperature sensor are adhesively fixed on the front surface or the back surface thereof, the fiber array and the planar heater.
In addition, each part has a recess of a size that does not come into contact with the positioning member, and a pool of silicone adhesive formed by filling the recess with a gel-like silicone adhesive, With the package structure characterized in that the heater and the fiber array are floatingly bonded and fixed, it is possible to provide a waveguide type optical module with stable optical characteristics.

(2) When the positioning member is calcium silicate, hard urethane, phenol foam, or the like, it is possible to provide a heating and holding waveguide type optical module with low power consumption.

[0043]

In summary, according to the present invention, a waveguide type optical module with low power consumption and low cost is provided.

[Brief description of drawings]

FIG. 1 is a diffusion exploded perspective view of a waveguide type optical module of the present invention.

FIG. 2 is a perspective view showing an embodiment of a waveguide type optical module of the present invention.

FIG. 3 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

FIG. 4 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

FIG. 5 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

FIG. 6 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

FIG. 7 is a perspective view showing another embodiment of the waveguide type optical module of the present invention.

[Explanation of symbols]

1 Optical waveguide 2 Temperature sensor 3-sided heater 4 Lower positioning member 4a recess 5 Upper positioning member 6 base parts 7 Cover parts 8 optical fibers 9 Optical fiber array 10 Gel Silicone Adhesive (Gel Member)

Claims (2)

[Claims] 1. A waveguide type optical module in which the temperature of the optical waveguide is adjusted by a heater so that the optical waveguide is within a predetermined temperature range. A planar heater is attached to the optical waveguide, and the planar heater is provided in the recess of the lower positioning member. A waveguide type in which a gel-like member is filled, at least one of the optical waveguide and the planar heater is immersed in the gel-like member, and the lower positioning member is covered with an upper positioning member. Optical module. 2. The waveguide type optical module according to claim 1, wherein the upper positioning member and the lower positioning member are made of a resin such as calcium silicate, hard urethane or phenol foam.