JP2003318298A - Vacuum package and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum package having such a structure as a high vacuum state can be brought about in the package easily and the focus of a condensing lens can be adjusted simultaneously when a light receiving sensor, e.g. an infrared sensor, is contained. <P>SOLUTION: A stem 2 for supporting the infrared sensor 5 while compressing a telescopic bellows 11 and a lens holder 7 bonded with the condensing lens 10 are coupled through the bellows 11 such that an airtight space surrounded by the stem 2, the lens holder 7 and the bellows 11 becomes the interior 1a of the package. The interior 1a of the package is brought into high vacuum state by moving the lens holder 7 in the direction receding from the stem 2 thereby increasing the volume of the interior 1a of the package. The position for fixing the lens holder 7 to the stem 2 is fixed using a screw member 6. <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 vacuum package that accommodates a sensor chip such as an infrared sensor in a vacuum environment.

[0002]

2. Description of the Related Art Conventionally, infrared cameras which detect infrared rays emitted from an object by an infrared sensor and output them as electric signals have been widely used. The infrared sensor used in such an infrared camera has a property that it is easily affected by heat from the outside. Therefore, the infrared sensor, as disclosed in JP-A-8-21764,
It is generally housed and used in a package kept in a high vacuum state. As described above, by housing the infrared sensor inside the package kept in a high vacuum state, heat transfer from the outside to the infrared sensor is blocked, and high detection sensitivity can be obtained.

In the conventional structure disclosed in Japanese Patent Laid-Open No. 8-21764, an infrared sensor is housed inside a mechanically strong container. The container is opened at a position facing the infrared sensor housed inside, and the airtightness is ensured by blocking the opening with a condenser lens. Then, the inside of this container is evacuated by a vacuum pump to be in a high vacuum state. The condenser lens is for condensing infrared radiation emitted from an object on an infrared sensor housed inside the container.

[0004]

By the way, in the conventional structure as described above, the inside of the container is brought into a high vacuum state by the vacuum exhaust using the vacuum pump. There is a problem that it is difficult to obtain a degree of vacuum that can completely block the heat transfer of the. Further, if the degree of vacuum inside the container is raised to a certain degree and the degree of vacuum is further increased by vacuum evacuation using a vacuum pump, there is a problem that it takes a long time for the evacuation.

Such a problem is not limited to the infrared sensor, but a sensor chip required to be used in a vacuum environment, for example, a yaw rate sensor using a vibration type gyro is housed in a container, and the inside of the container is vacuumed by a vacuum pump. This is a common problem when exhausting air.

Further, in the conventional structure as described above, since the condenser lens is fixed to the container for accommodating the infrared sensor, the focus caused by manufacturing variations of the condenser lens and other members. There is also a problem that it cannot cope with the gap. Especially when the optical system is telephoto, the detection sensitivity of the infrared sensor will be substantially reduced even if the focus of the condenser lens is slightly shifted.
There is a strong demand for a structure that allows delicate focus adjustment of the condenser lens.

The present invention was devised in view of the above conventional circumstances, and when the inside of the package can be easily brought to a high vacuum state and a light receiving sensor such as an infrared sensor is housed, It is an object of the present invention to provide a vacuum package having a structure capable of adjusting the focus of a condenser lens at the same time as increasing the vacuum inside the package.

[0008]

According to a first aspect of the present invention, there is provided a vacuum package in which a sensor chip is housed in a package in a high vacuum state and heat transfer to the sensor chip from the outside of the package is cut off. A supporting member that supports the sensor chip, an opposing member that is disposed so as to face the supporting member, and an extendable side trunk member that connects the supporting member and the opposing member while maintaining airtightness. A positioning member that fixes the position of the facing member with respect to the support member, and moves the facing member in a direction in which the facing member is separated from the support member while extending the side trunk member, By fixing the position with respect to the support member, the inside of the package surrounded by the support member, the facing member, and the side body member can be in a high vacuum state. The one in which the features.

The invention described in claim 2 is the same as claim 1.
In the vacuum package described in the above item 1, the positioning member has a screw mechanism for fixing the facing member with respect to the supporting member at an arbitrary position while continuously changing the position thereof.

The invention described in claim 3 is the same as claim 1
Alternatively, in the vacuum package according to the second aspect, a bellows-shaped bellows is used as the side body member.

The invention described in claim 4 is the same as claim 1.
4. In the vacuum package according to any one of 3 to 3, the sensor chip is an infrared sensor that detects incident infrared light from the outside of the package, an opening hole is provided in the facing member, and the incident hole enters the opening hole. A condensing lens for condensing infrared light on the infrared sensor is hermetically bonded.

The invention according to claim 5 is the same as claim 4
In the vacuum package according to claim 7, between the support member and the positioning member, the position of the facing member with respect to the support member is finely adjusted to adjust the focus position of the condenser lens to the infrared sensor. Is provided.

The invention according to claim 6 is the same as claim 5
In the vacuum package described in [1], a piezo driver is used as the focus adjusting means.

The invention according to claim 7 is a method of manufacturing a vacuum package, wherein a sensor chip is housed inside a package in a high vacuum state, and heat transfer to the sensor chip from outside the package is shut off. A first step of mounting the sensor chip on a support member and air-tightly joining one end side of a side trunk member that is expandable and contractable to the support member so as to surround the sensor chip; and compressing the side trunk member. In this state, the other end of the package is hermetically bonded to a facing member arranged to face the supporting member under a predetermined vacuum environment, and the inside of the package surrounded by the supporting member, the facing member, and the side body member is closed. The second step of sealing in a state of being evacuated, and moving the facing member in a direction of separating from the supporting member while extending the side body member to reduce the internal volume of the package. A third step of increasing the degree of vacuum was large and, is characterized in that it has a fourth step of fixing the positioning member position relative to the support member of the opposing member.

[0015]

According to the vacuum package of the first aspect of the invention, the sensor can be obtained by increasing the volume inside the package by moving the opposing member away from the supporting member while extending the expandable side trunk member. Since the structure is such that the degree of vacuum inside the package that contains the chips is raised, compared to the case where the degree of vacuum is raised by vacuum exhaustion using a vacuum pump, the inside of the package can be in a desired high vacuum state easily and in a short time It is possible to increase the sensitivity of the sensor chip.

Further, according to the second aspect of the invention, the position of the facing member with respect to the supporting member can be continuously changed and fixed at a desired position by the screw mechanism of the positioning member, so that the inside of the package is optimal. The high vacuum state can be set, and the optimum high vacuum state can be appropriately maintained.

According to the vacuum package of the third aspect, since the bellows-shaped bellows is used as the side body member that connects the supporting member and the facing member, the height between the supporting member and the facing member is high. It is possible to easily move the facing member while ensuring airtightness, and it is possible to extremely easily bring the inside of the package into a desired high vacuum state.

According to the vacuum package of the fourth aspect, since the condenser lens for condensing the incident infrared rays on the infrared sensor is airtightly joined to the opening hole of the opposing member, the opposing member is moved to move the inside of the package. When increasing the vacuum degree, the focus of the condenser lens can be adjusted, and the detection sensitivity of the infrared sensor can be further increased.

Further, according to the fifth aspect of the present invention, since the focus adjusting means is provided between the supporting member and the positioning member, the vacuum package is assembled not only when the vacuum package is manufactured but also when it is used. The focus of the optical lens can be constantly adjusted.

Further, according to the sixth aspect of the present invention, since the piezo driver is used as the focus adjusting means and the focus adjustment of the condenser lens can be performed by electrical control, the focus adjustment of the condenser lens is extremely performed. It can be performed with high precision.

Further, according to the method of manufacturing a vacuum package of claim 7, the expandable side body member is compressed to bring the support member and the opposing member into close proximity to each other, and the inside of the package is sealed in a vacuumed state. After that, by extending the side body member and moving the facing member in a direction away from the support member to increase the volume inside the package, the degree of vacuum inside the package in which the sensor chip is housed is increased. Therefore, the inside of the package can be easily brought to a desired high vacuum state in a short time, as compared with the case where the degree of vacuum is increased by vacuum evacuation using a vacuum pump.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the drawings used in the following description are shown in a partially deformed form in order to facilitate understanding of the features of the present invention, and the dimensional ratios and the like of the respective portions do not necessarily match the actual ones. Further, the structure and the like of each unit described below show a specific example to which the present invention is applied, and can be appropriately changed according to design conditions and the like.

(First Embodiment) FIG. 1 is a sectional view showing an example of a vacuum package to which the present invention is applied. The vacuum package 1 shown in FIG. 1 includes a stem (support member) 2 formed into a circular plate shape. The stem 2 has a thickness capable of maintaining sufficient strength to withstand a high vacuum state,
A pair of pin insertion holes 2a are formed so as to penetrate in the thickness direction. Terminal pins 3 serving as external connection terminals are inserted into the pin insertion holes 2a, and these terminal pins 3 are made into a stem 2 by a hermetic 4 having a high airtightness.
It is fixed to.

An infrared sensor 5 is die-bonded to one main surface portion of the stem 2 at a substantially central portion thereof. The pad of the infrared sensor 5 and the terminal pin 3
The tip end of the infrared sensor 5 is connected by wire bonding, and the terminal pin 3 functions as an external connection terminal of the infrared sensor 5. Further, on the outer peripheral side of the stem 2, a screw hole 2b is formed penetrating in the thickness direction thereof, into which a tip portion of a screw member 6 described later is screwed. This screw hole 2b
Has a female screw shape corresponding to the male screw shape of the screw member 6.

A lens holder (opposing member) 7 is arranged at a position facing one main surface portion of the stem 2. The lens holder 7 is formed in a circular plate shape having substantially the same diameter as that of the stem 2, and has a thickness sufficient to withstand a high vacuum state, like the stem 2.

An opening hole 7a is provided at a substantially central portion of the lens holder 7 so as to penetrate in the thickness direction thereof. And
An end edge of the opening 7a on the one main surface portion side of the lens holder 7 facing the stem 2 is formed as a flange portion 8 so as to project toward the stem 2 side. A condenser lens 10 is airtightly bonded to the other main surface portion of the lens holder 7 by an airtight adhesive material 9 such as low melting point glass. With this condenser lens 10, an opening hole 7a of the lens holder 7 is formed.
Is shielded. The condenser lens 10 is for condensing incident infrared light from the outside of the package on the infrared sensor 5. Furthermore, on the outer peripheral side of the lens holder 7,
A screw insertion hole 7b is formed so as to pass through in the thickness direction and through which the proximal end side of the screw member 6 is inserted. The screw insertion hole 7b is slightly larger in diameter than the screw member 6 so that the screw member 6 can be loosely inserted.

A bellows (side body member) 11 is arranged between the opposing surfaces of the stem 2 and the lens holder 7 so as to cover the infrared sensor 5 supported by the stem 2 and the opening hole 7a of the lens holder 7. ing. The bellows 11 is made of a material having airtightness and formed into a bellows shape. One end of the bellows 11 is airtightly joined to one main surface of the stem 2 and the other end of the bellows 11 is one main surface of the lens holder 7. The stem 2 and the lens holder 7 are connected to each other while maintaining airtightness by being airtightly joined to the flange portion 8 formed on the. Then, the stem 2 and the lens holder 7
By being connected by the bellows 11, the bellows 11 can be moved in the directions of approaching and separating from each other while expanding and contracting the bellows 11, and the distance between the facing surfaces of both can be made variable.

In the vacuum package 1 to which the present invention is applied,
An airtight space surrounded by the stem 2, the lens holder 7, and the bellows 11 is a package interior 1a, and the infrared sensor 5 is arranged in the package interior 1a. Then, the bellows 11 is compressed to reduce the volume of the package interior 1a, and
a is set to a vacuum state to some extent, and the bellows 11 is extended to move the lens holder 7 in a direction in which the lens holder 7 is separated from the stem 2 to increase the volume inside the package 1a, thereby increasing the vacuum degree inside the package 1a. It is designed to be in a high vacuum state.

When the lens holder 7 is separated from the stem 2 and the inside of the package 1a is in a high vacuum state, the position of the lens holder 7 with respect to the stem 2 is fixed by a screw member (positioning member) 6. . The screw member 6 has its proximal end inserted through a screw insertion hole 7 b provided in the lens holder 7, and its distal end has the stem 2
It is screwed into the screw hole 2b provided in the. The lock nut 6a supports one main surface side of the lens holder 7 to fix the position of the lens holder 7 with respect to the stem 2. The screw member 6
In order to maintain the parallelism between the stem 2 and the lens holder 7 and suppress the optical axis tilt of the condenser lens 10, it is desirable to fix the stem 2 and the lens holder 7 at at least three places. Further, in order to uniformly disperse the stress due to the high vacuum inside the package 1a, it is desirable that the screw members 6 are arranged at equal intervals.

In the vacuum package 1 to which the present invention having the above-described structure is applied, the lens holder 7 is moved in the direction in which it is separated from the stem 2 while expanding the expandable bellows 11 to increase the volume of the inside 1a of the package. As a result, the degree of vacuum inside the package 1a in which the infrared sensor 5 is arranged is raised to a high vacuum state. For example, the infrared sensor is arranged inside a mechanically strong container. As compared with the conventional structure in which the inside of this container is evacuated to high vacuum by using a vacuum pump, the inside 1a of the package can be easily evacuated to high vacuum in a short time. Particularly, since the degree of vacuum can be easily improved from a high vacuum state, which is difficult to realize with the conventional structure, in a short time, the sensitivity of the infrared sensor 5 can be made extremely excellent.

Further, in this vacuum package 1, since the position of the lens holder 7 with respect to the stem 2 is fixed by using the screw member 6, while the position of the lens holder 7 with respect to the stem 2 is continuously changed. It can be fixed at the desired position. Therefore, the package interior 1a surrounded by the stem 2, the lens holder 7, and the bellows 11 can be set to an optimum high vacuum state, and the optimum high vacuum state can be appropriately maintained.

Further, in this vacuum package 1, the stem 2 and the lens holder 7 are connected by a bellows-shaped bellows 11 so that the bellows 11 can be expanded and contracted.
Since the space between the facing surfaces of the stem 2 and the lens holder 7 can be adjusted by moving, the airtightness between the stem 2 and the lens holder 7, that is, the airtightness of the inside 1a of the package can be improved. It is possible to bring the inside 1a of the package into a desired high vacuum state very easily while ensuring good conditions.

Further, in this vacuum package 1, the stem 2 is disposed so as to face the stem 2 supporting the infrared sensor 5.
The condenser lens 10 for condensing the incident infrared rays on the infrared sensor 5 is hermetically joined to the lens holder 7 whose distance between the lens holder 7 and the lens holder 7 is variable. Move it inside the package 1
When increasing the degree of vacuum of a, the focus of the condenser lens 10 can be adjusted, and the detection sensitivity of the infrared sensor 5 can be further increased. Particularly, in this vacuum package 1, the screw member 6 is used as a member for fixing the position of the lens holder 7, and the position of the lens holder 7 with respect to the stem 2 can be continuously changed and fixed at a desired position. Therefore, the focus adjustment of the condenser lens 10 can be performed with extremely high accuracy.

Here, a method of manufacturing the vacuum package 1 as described above will be described with reference to FIGS.

To manufacture the vacuum package 1, first,
The infrared sensor 5 is die-bonded on one main surface portion of the stem 2, and the terminal pin 3 is inserted into the pin insertion hole 2a of the stem 2.
Through and fix with Hermetic 4. Then, the pad of the infrared sensor 5 and the tip of the terminal pin 3 are connected by wire bonding.

Next, the bellows 11 in a compressed state is
The infrared sensor 5 is mounted on one main surface portion of the stem 2 so as to surround the infrared sensor 5, and one end of the infrared sensor 5 is hermetically joined to the one main surface portion of the stem 2 by welding or the like. Further, on the other main surface portion of the lens holder 7, an airtight adhesive material 9 such as low melting point glass is formed.
Is used to hermetically bond the condenser lens 10, and the condenser lens 10 shields the opening hole 7a of the lens holder 7.

Next, as shown in FIG. 2, the condenser lens 10
The lens holder 7 to which is joined is brought close to the stem 2,
The other end of the bellows 11 joined to the stem 2 in a compressed state is airtightly joined to the flange portion 8 of the lens holder 7 by electron beam welding or the like. As a result, the infrared sensor 5
The stem 2 on which is mounted and the lens holder 7 to which the condenser lens 10 is joined are connected by the bellows 11 in a compressed state, and the stem 2, the lens holder 7 and the bellows 1 are connected.
1 and 1 form an airtight space, and this airtight space is the inside 1a of the package. At this time, the airtight bonding between the bellows 11 and the lens holder 7 is performed in a predetermined vacuum environment. Thereby, the package interior 1a surrounded by the stem 2, the lens holder 7 and the compressed bellows 11
Will be hermetically sealed while being evacuated.

Next, the stem 2 and the lens holder 7 connected by the bellows 11 are taken out under atmospheric pressure. At this time, since the bellows 11 is in a compressed state, the bellows 1
The inconvenience that 1 is abruptly compressed by the atmospheric pressure to cause deformation is suppressed in advance.

Next, as shown in FIG. 3, the screw member 6 is inserted into the screw insertion hole 7b of the lens holder 7 to attach the lock nut 6a, and the tip end thereof is screwed into the screw hole 2b of the stem 2. . Then, by rotating the lock nut 6 a, the lens holder 7 is moved in a direction in which it is separated from the stem 2. At this time, the bellows 11 connecting the stem 2 and the lens holder 7 expands, and the volume of the package interior 1a increases. As a result, the degree of vacuum inside the package 1a is increased. Further, the lens holder 7 and the infrared sensor 5 to which the condenser lens 10 is joined.
The focus of the condenser lens 10 is also adjusted by adjusting the distance from the stem 2 on which the is mounted.

After setting the position of the lens holder 7 with respect to the stem 2 to a desired position, the screw member 6 is then tightened toward the stem 2 while maintaining the position of the lock nut 6a. As a result, the position of the lens holder 7 with respect to the stem 2 is fixed by the screw member 6, and the vacuum package 1 shown in FIG. 1 is completed.

Vacuum package 1 manufactured as described above
The volume of the package inside 1a hermetically sealed under a predetermined vacuum environment is increased by atmospheric pressure, and
Since the degree of vacuum in this package is increased, 1
The sensitivity of the infrared sensor 5 housed in a can be made extremely good. Here, the relationship between the sensor sensitivity and the degree of vacuum will be described with reference to FIG. 4, taking a thermopile type infrared sensor that utilizes thermoelectromotive force of a thermocouple as an example. Note that the relationship between the sensor sensitivity and the degree of vacuum shown in FIG. 4 is similarly applied to other types of infrared sensors, such as a bolometer-type infrared sensor that utilizes a resistance value change of a resistor due to a temperature change. Is.

This infrared sensor, as shown in FIG.
When the degree of vacuum is further increased at the boundary of 5 Torr, the sensor sensitivity is improved due to a sharp change. Here, the infrared sensor is housed in the package interior 1a of the vacuum package 1 described above, and after the package interior 1a is hermetically sealed under a vacuum environment of, for example, about 500 mTorr, the volume of the package interior 1a is increased five times by atmospheric pressure. , The vacuum degree inside the package 1a is P1 · V1 / T1 = P2 ·
From Boyle-Charles' law expressed by V2 / T2 (P is pressure, V is volume, T is temperature, and pressure is inversely proportional when volume is changed at constant temperature).
It can be seen that it becomes about Torr.

In the high vacuum state of 100 mTorr, the infrared sensor described above has an extremely high sensor sensitivity corresponding to almost the saturation level. Thus, by using the vacuum package 1 to which the present invention is applied, the sensitivity of the infrared sensor can be significantly improved. Moreover, since the vacuum package 1 can easily and quickly increase the vacuum inside the package 1a as described above, it is extremely useful as a package for accommodating an infrared sensor in a vacuum environment.

In the above, the example in which the present invention is applied to the vacuum package 1 which houses the infrared sensor 5 for detecting the infrared radiation emitted from the object and converting it into an electric signal has been specifically described. The present invention is not limited to the above example, and can be effectively applied to a vacuum package that accommodates any sensor chip required to be used in a vacuum environment, such as a yaw rate sensor using a vibration gyro.

The vacuum package 1 described above is
It shows one specific configuration example to which the present invention is applied, and various modifications of the detailed mechanism and the like are possible without departing from the spirit of the present invention.

For example, in the above-mentioned vacuum package 1,
Although the screw member 6 is used as a positioning member for fixing the position of the lens holder 7 with respect to the stem 2,
Instead of the screw member 6, as shown in FIGS.
Lens holder 7 for stem 2 using cylindrical member 12
The position of may be fixed.

In this example, a thread groove 7c functioning as a male screw is formed on the outer peripheral end of the lens holder 7 to which the condenser lens 10 is joined. The inner diameter of the cylindrical member 12 is substantially the same as the outer dimension of the lens holder 7, and the inner peripheral wall of the cylindrical member 12 has a thread groove 12a as a female screw corresponding to the thread groove 7c of the lens holder 7. Has been formed. Then, the lens holder 7 is screwed into the inside of the cylindrical member 12.

In this example, the stem 2 and the lens holder 7 are connected by the compressed bellows 11 and the inside 1a of the package is hermetically sealed at a predetermined vacuum degree, as shown in FIG. The cylindrical member 12 is attached from the 7 side. The lens holder 7 is housed inside the cylindrical member 12, and the thread groove 7 c of the lens holder 7 and the cylindrical member 12 are accommodated.
The cylindrical member 12 is engaged with the screw groove 12a of
When the lens holder 7 is rotated, the lens holder 7
1 is extended and is moved in a direction away from the stem 2. This allows the inside of the package 1
The degree of vacuum of “a” is increased, and the focus of the condenser lens 10 joined to the lens holder 7 is adjusted.

The lens holder 7 for the stem 2
When the rotating operation of the cylindrical member 12 is stopped when the position of is set to the desired position, the cylindrical member 12 receives the stress due to the vacuum state of the package interior 1a, and the cylindrical member 12 is urged toward the stem 2 side, and the lens holder 7 moves. The position with respect to the stem 2 is fixed, and the inside 1a of the package is maintained in a high vacuum state.

At this time, it is desirable that one end of the bellows 11 that is airtightly joined to the stem 2 be in a state of being projected to the outside of the cylindrical member 12. If one end side of the bellows 11 is projected to the outside of the cylindrical member 12 in this way, the one end side of the bellows 11 will be sandwiched between the stem 2 and the cylindrical member 12, as shown in FIG. It is possible to prevent inconvenience that the airtightness of the inside 1 a of the package is impaired due to the peeling off of the welding 11 or the like.

As described above, when the position of the lens holder 7 with respect to the stem 2 is fixed by using the cylindrical member 12, the position of the lens holder 7 with respect to the stem 2 can be adjusted only by rotating the cylindrical member 12. Since the adjustment can be performed, the work of adjusting the focus of the condenser lens 10 can be extremely easily performed while increasing the degree of vacuum inside the package 1a. Further, in this example, since the cylindrical member 12 is arranged on the outer peripheral side of the bellows 11, the cylindrical member 12 can also protect the bellows 11.

In the above example, the lens holder 7 is screwed into the inside of the cylindrical member 21, and the stem 2 receives the biasing force acting on the cylindrical member 21 due to the stress due to the vacuum state inside the package 1a. However, conversely, the structure in which the stem 2 is screwed into the inside of the cylindrical member 21 and the lens holder 7 receives the biasing force acting on the cylindrical member 21 due to the stress due to the vacuum state of the package interior 1a is also the same. The effect of can be obtained. In this case, the external dimensions of the stem 2 are designed so as to substantially match the internal diameter of the cylindrical member 21, and the thread groove 12 a of the cylindrical member 12 is formed at the outer peripheral end of the stem 2.
Therefore, a thread groove corresponding to is formed.

By the way, in order to always use the infrared sensor 5 in an optimum state, the focus of the condenser lens 7 can be instantly adjusted not only when the vacuum package 1 is manufactured but also when it is used. Is desirable. In order to satisfy such a requirement, as shown in FIG. 7, between the stem 2 and the cylindrical member 12 as a positioning member, the position of the lens holder 7 with respect to the stem 2 is finely adjusted to adjust the position of the condenser lens 7. A height adjusting mechanism (focus adjusting means) 13 for performing focus adjustment may be provided. As in this example, the height adjusting mechanism 13 is provided between the stem 2 and the cylindrical member 12, and the height adjusting mechanism 13 is provided.
By making it possible to finely adjust the position of the lens holder 7 with respect to the stem 2, the focus of the condenser lens 7 can be constantly adjusted, and the infrared sensor 5 can always be used in an optimum state.

Here, as the height adjusting mechanism 13, for example, a piezo driver capable of changing the volume according to the driving voltage is suitable. When this piezo driver is used as the height adjustment mechanism 22, the focus adjustment of the condenser lens 7 can be performed electrically. Therefore, the focus adjustment of the condenser lens 7 can be performed instantaneously and with extremely high accuracy. You can

[Brief description of drawings]

FIG. 1 is a sectional view of a vacuum package to which the present invention is applied.

FIG. 2 is a cross-sectional view illustrating a method of manufacturing the vacuum package, showing how the other end of a bellows, one end of which is airtightly joined to a stem, is airtightly joined to a lens holder in a compressed state.

FIG. 3 is a view for explaining the method of manufacturing the vacuum package, and is a cross-sectional view showing a state of fixing the position of the lens holder with respect to the stem using a screw member.

FIG. 4 is a diagram showing the relationship between the sensitivity of an infrared sensor and the degree of vacuum.

FIG. 5 is a view showing another vacuum package to which the present invention is applied, and is a cross-sectional view showing how the position of the lens holder with respect to the stem is fixed by using a cylindrical member.

FIG. 6 is a cross-sectional view of the vacuum package in which the position of the lens holder with respect to the stem is fixed by the cylindrical member.

FIG. 7 is a sectional view showing still another vacuum package to which the present invention is applied.

[Explanation of symbols]

1 vacuum package 2 stems 5 infrared sensor 6 screw members 7 lens holder 10 Condensing lens 11 Bellows 12 Cylindrical member

Claims (7)

[Claims] 1. A vacuum package in which a sensor chip is housed inside a package in a high vacuum state and heat transfer to the sensor chip from the outside of the package is blocked, a support member for supporting the sensor chip, and the support. A facing member disposed so as to face the member, a stretchable side trunk member that connects the supporting member and the facing member while maintaining airtightness, and a position of the facing member with respect to the supporting member is fixed. A positioning member, and moving the facing member away from the supporting member while extending the side trunk member, and fixing the position of the facing member with respect to the supporting member by the positioning member, thereby supporting the supporting member. A vacuum package, characterized in that a high vacuum state is created inside a package surrounded by a member, the facing member, and the side body member. 2. The positioning member has a screw mechanism for fixing the facing member with respect to the supporting member at an arbitrary position while continuously changing the position of the facing member. Vacuum package. 3. The vacuum package according to claim 1, wherein a bellows-shaped bellows is used as the side body member. 4. The sensor chip is an infrared sensor that detects incident infrared light from the outside of the package, and an opening hole is provided in the facing member, and the infrared light sensor detects the incident infrared light in the opening hole. 4. A condensing lens for condensing the light on the surface is airtightly bonded.
The vacuum package according to any one of 1. 5. A focus adjustment unit is provided between the support member and the positioning member to finely adjust the position of the facing member with respect to the support member to adjust the focus position of the condenser lens to the infrared sensor. The vacuum package according to claim 4, wherein the vacuum package is provided. 6. The vacuum package according to claim 5, wherein a piezo driver is used as the focus adjusting means. 7. A method of manufacturing a vacuum package, wherein a sensor chip is housed inside a package in a high vacuum state, and heat transfer to the sensor chip from the outside of the package is shut off. A first step of mounting and mounting the one end side of the side trunk member which is expandable and contractible to the support member so as to surround the sensor chip, and the other end side of the side trunk member in a compressed state. The opposing member, which is disposed so as to face the member, is airtightly bonded in a predetermined vacuum environment, and the inside of the package surrounded by the supporting member, the opposing member and the side body member is sealed in a vacuumed state. A second step; and a step of moving the facing member away from the support member while extending the side trunk member, increasing the volume inside the package and increasing the vacuum degree. And a fourth step of fixing the position of the facing member with respect to the support member by a positioning member.