JP6727564B2 - Imaging device for vacuum container - Google Patents

Description

The present invention relates to an image pickup apparatus for a vacuum container, and more particularly, to an image pickup apparatus configured to be able to take an image inside a vacuum container depressurized to a high vacuum or an ultrahigh vacuum.

Work such as film formation on a substrate, which is carried out during semiconductor manufacturing, which requires to be performed in a state where impurities are not mixed in or a reaction (for example, oxidation) with impurities is excluded is usually performed by vacuuming the inside. It is performed in a vacuum container.

Generally, such a vacuum container is provided with a peep window for observing the inside of the vacuum container from the atmosphere side. Through this peep window, the object to be treated is processed in the vacuum container. It is possible to observe the state of the processing being performed and the state of change, or to take an image.

However, in the observation and photographing performed through such a viewing window, it is not possible to observe the inside of the vacuum container in a wide range because the field of view is limited by the window frame, and the object to be processed is viewed from outside the vacuum container. Since it is observed, many restrictions are involved, such as being unable to approach the object to be processed for close-up photography.

Therefore, in order to be able to observe the object to be processed at a position closer to the inside of the vacuum container, it has been proposed to photograph the object to be processed by an imaging device arranged in the vacuum container.

As such an image pickup device, in Japanese Patent Application Laid-Open No. 2004-242242, an image pickup mechanism 110 including an optical system component such as a CCD camera is arranged in a vacuum container 103 in a state of being enclosed in a hermetically sealed container 104, and image pickup is performed. The imaging device 100 is described in which a display device 116 for displaying an image captured by the mechanism 110 and a recording circuit unit 115 are provided outside the vacuum container 103.

JP-A-9-93474

In the image pickup device 100 described in Patent Document 1 configured as described above, the image pickup mechanism 110 such as a CCD camera is introduced into the vacuum container 103 in a state of being enclosed in the closed container 104, and the display device 116 and the recording circuit are provided. Since the portion 115 is provided outside the vacuum container 103, the image capturing mechanism 110 such as a CCD camera is disposed inside the vacuum container 103 while preventing the atmospheric air from entering the vacuum container 103 from the outside. The object 102 can be photographed from a closer position.

However, even if the imaging device 100 described in Patent Document 1 can be used in the vacuum container 103 having a relatively low vacuum degree, it can be used in the high-vacuum or ultrahigh-vacuum vacuum container 103. Not not.

That is, the degree of vacuum in the vacuum container is increased so that a clean space with less impurities is required to generate a space with a higher degree of vacuum. Therefore, the introduction of a pollution source into the vacuum container is prevented. While it will be more strictly regulated, as the degree of vacuum inside the vacuum container becomes higher, what becomes a pollution source under atmospheric pressure or in a space of a low vacuum degree becomes a pollution source.

Here, looking at the image pickup device 100 described in Patent Document 1, the image pickup mechanism 110 and sensors housed in the closed container 104 arranged in the vacuum container 103, and the display device 116 provided outside the vacuum container 103. A part of the lead wire 125 connecting the recording circuit section 115 and the recording circuit section 115 is directly arranged in the vacuum container 103. However, the resin-based material such as vinyl covering the surface of the lead wire 125 has moisture on its surface and inside. When a polymer containing a gas or a gas source is placed in a space of high vacuum or ultra-high vacuum, these water and molecules are released into the vacuum space and pollute the space.

The closed container 104 that houses the image pickup mechanism 110 such as a CCD camera has the same problem as the lead wire 125 when it is made of resin itself or is coated with resin such as paint. In addition, even if the closed container 104 is made of metal, when it is placed in a space of high vacuum or ultrahigh vacuum, residual gas on the surface is released into the vacuum space and becomes a pollution source. obtain.

Therefore, in order to make such an image pickup apparatus 100 applicable to photographing inside a vacuum container which is set to a high vacuum or an ultrahigh vacuum, the hermetically sealed container 104 which houses the image pickup mechanism 110 is airtightly configured. This is not enough, and the closed container 104 itself needs to have a surface structure that does not become a pollution source.

Further, the image pickup apparatus 100 described in Patent Document 1 described above is configured so that the closed container 104 can be moved back and forth within the vacuum container 103, and thereby, the object to be processed 102 is approached and separated. However, depending on this configuration, only one direction of the processing object 102 can be photographed, and the photographing direction cannot be changed. Be restricted.

In order to solve such a problem, in addition to the forward and backward movement, the closed container 104 can be moved vertically and horizontally, and the closed container 104 can be moved at any position before and after the movement. Although it is necessary to provide a structure for holding the structure so that it does not move, the above-mentioned Patent Document 1 does not disclose or suggest such a structure.

Further, in the image pickup apparatus 100 described in the above-mentioned Patent Document 1, when the processing performed in the vacuum container 103 is processing such as film formation, the vapor deposition material adheres to the lens 111 provided in the CCD camera or the like. When it is contaminated, there is a problem that photography cannot be performed, and the heat resistance is not sufficient.

Therefore, the present invention has been made in order to solve the above-mentioned drawbacks of the prior art, and a first object of the present invention is to prevent at least one atmosphere from being introduced into the vacuum container while at least one of the image pickup devices. The inside of the vacuum container can be photographed by inserting the part, and even if it is arranged in a high-vacuum or ultra-high-vacuum vacuum container, it does not become a source of impurity gas, Therefore, it is an object of the present invention to provide an imaging device for a vacuum container, which can maintain the cleanliness of the vacuum container.

Another object of the present invention is, in addition to the above objects, that the observation direction with respect to the object to be processed is variable, that the posture can be maintained in a state where the observation direction is changed, and that the observation direction is changed by a vacuum. Any one or more, preferably all, of being able to be operated from the outside of the container, being able to prevent photography from being disabled due to contamination of the lens, and improving heat resistance. An object of the present invention is to provide an imaging device for a vacuum container that can realize the above.

The means for solving the problems will be described below together with the reference numerals used in the embodiments for carrying out the invention. This code is provided to clarify the correspondence between the description of the claims and the description of the modes for carrying out the invention, and needless to say, is limited to the interpretation of the technical scope of the present invention. It is not used.

In order to achieve the above-mentioned object, the imaging device 10 for a vacuum device of the present invention comprises:
In an image pickup device 10 including an image pickup mechanism 30 including an image pickup device and a casing 20 that is disposed in the vacuum container 50 and that houses at least a part of the image pickup mechanism 30, the image pickup device 10 is used for photographing in the vacuum container 50. ，
The casing 20 has a window 28 formed on one end 20a side, a sealing body 29 that seals the window 28 and is made of a translucent material such as glass or sapphire, and a housing formed inside the window 28. A space 23 and a flange 24 provided on the other end 20b side,
The one end 20a side (the side where the window 28 is formed) of the casing 20 is directed into the vacuum container 50, and the casing 20 is inserted into the opening 52 formed in the wall surface 51 of the vacuum container 50 from the outside of the vacuum container 50. While maintaining the airtightness of the vacuum container 50 by sealing the opening 52 by attaching the flange 24 to the fixing flange 54 attached to the opening 52 on the outside of the container 50, The casing 20 is configured to be arranged in the vacuum container 50,
The image pickup mechanism 30 includes a light guide member (lens 32 of the camera module 31 and fiberscope 33 in the embodiment) that transmits the received light and emits the light toward the image pickup element. By accommodating the light receiving portion (the light receiving surface of the lens 32, the tip portion 33a of the fiber scope 33) in the housing space 23 so as to face the sealing body 29, the inside of the vacuum container 50 can be photographed. The
The casing 20 is made of stainless, the outer surface of surface roughness were polished until the 0.4~0.8μm in Ra, and electrolytic polishing treatment, by vacuum degassing process involving heating above 300 ° C., throughput in outgassing rate after room temperature exhaust 10 hours ^{2 × 10 -7 (Pa · m} 3 / sm 2) below in the outgassing rate measurement by law, and the gas release rate after 6 hours baked at a temperature of 120 ° C. Is formed to have a detection sensitivity of 1×10 ⁻⁹ (Pa·m ³ /sm ² ) or less (claim 1).

The image pickup mechanism 30 can be configured by a camera module 31 such as a CCD camera module or a CMOS camera module. In this case, the light receiving surface of a lens 32 provided in the camera module 31 is connected to the image pickup mechanism 30. As the light receiving portion of the light guide member, a configuration may be adopted in which the camera module 31 is housed in the housing space 23 so as to face the sealing body 29 (claim 2: see FIG. 2 ).

In the present invention, the “camera module” is a module in which an image pickup device such as a CCD image sensor or a CMOS image sensor and components necessary for image pickup by the image pickup device are modularized, and is configured together with the image pickup device. Examples of the elements include a lens arranged in front of the image sensor, an AD converter for converting an output signal of the image sensor into a digital signal, and a driver for driving a vertical shift register when the image sensor is a CCD image sensor. A pulse generator that generates a timing pulse for driving the image sensor or various signal processing, an image processing LSI, or the like can be used, but the camera module does not need to include all of the components listed here. Further, it may include components not listed here.

As described above, in the configuration in which the camera module 31 is arranged as the imaging mechanism 30 in the housing space 23 in the casing 20, a wireless device (not shown) capable of wirelessly outputting the image data generated by the camera module 31 is used. A driving battery (not shown) for driving the camera module 31 and the wireless device may be housed in the housing space 23 of the casing 20 (claim 3).

Alternatively, instead of this configuration, one end of a USB cable 34 capable of outputting the image data generated by the camera module 31 and capable of supplying driving power to the camera module 31 is connected to the camera module 31. The other end of the USB cable 34 may be extended from the other end 20b of the casing 20 to the outside of the casing 20 (claim 4: see FIGS. 2 to 4).

Further, as described above, a fiberscope 33 is provided as the light guide member of the image pickup mechanism 30 instead of the structure in which the camera module 31 is housed in the housing space 23 of the casing 20.
The tip portion 33a of the fiberscope 33 is disposed as the light receiving portion so as to face the sealing body 29 and is disposed in the housing space 23 in the casing 20, and the other end of the fiberscope 33 is disposed in the casing 20. A configuration may be adopted in which it is extended from the other end 20b to the outside of the casing 20 and is arranged on the front surface of the image pickup device (the camera module 31 incorporating the image pickup device in the illustrated example) arranged outside the casing 20. (Claim 5: See FIG. 5).

The casing 20 includes a neck portion 21 formed on the flange 24 side and a head portion 22 provided on the tip end side of the neck portion 21,
The accommodation space 23 may be formed in the head portion 22 and the neck portion 21 may be formed of a flexible tube (claim 6: FIGS. 2 to 4 and 6 ).

Further, when the neck portion 21 is formed of a flexible tube, the operation knob 61 provided outside the vacuum container 50 is connected to the head portion 22 at one end and is connected to the operation knob 61 at the other end. A swing mechanism 60 that includes the member 62 and swings the head portion 22 by operating the operation knob 61 may be included in the configuration of the imaging device 10 (claim 7: see FIG. 6).

The connecting member 62 of the swinging mechanism 60 can be configured by a connecting rod, but a wire may be used as the connecting member 62 instead of this configuration (claim 8).

Further, the swinging mechanism 60 may be formed of a commercially available wobble stick (claim 9).

A detachably attached attachment 40 is provided at the one end 20a of the casing 20, and is attached to the front of the sealing body 29 by the attachment 40 in a detachable manner and is made of a transparent material such as glass or sapphire. The protective cover 41 may be provided [Claim 10: see FIG. 8(A)].

Further, a metal cover such as stainless steel or gold surrounding each casing may be provided on the outer periphery of the casing 20 as a heat shield layer (claim 11).

When the anti-adhesion protector 41 is provided, it may be made of lead glass so that the anti-adhesion protector 41 has the function of an X-ray filter.

As described above, in the configuration in which the camera module 31 is provided in the accommodation space 23, it is preferable to provide the cooling structure 70 for cooling the camera module 31 (claim 12: see FIGS. 3 and 4).

The cooling structure 70 includes a cooling block 71 that covers the camera module 31 in the accommodation space 23, a refrigerant introduction pipe 72 that communicates with an inlet of a refrigerant passage provided in the cooling block 71, and the refrigerant. The refrigerant discharge pipe 73 communicates with the outlet of the flow path, and the refrigerant introduction pipe 72 and the refrigerant discharge pipe 73 are extended from the other end 20b of the casing 20 to the outside of the vacuum container 50. (Claim 13: see FIG. 3).

Further, instead of the above configuration, as the cooling structure 70, one end is opened toward the camera module 31 in the accommodation space 23, and the other end is extended from the other end 20b of the casing 20 to the outside of the vacuum container 50. A refrigerant gas introduction pipe 75 may be provided, and an air release hole 76 may be provided in the other end 20b of the casing 20 to release the gas in the casing 20 to the outside of the vacuum container 50 (claim 14). : See FIG. 4).

With the configuration of the present invention described above, according to the imaging device 10 for a vacuum container of the present invention, the following remarkable effects can be obtained.

The casing 20 of the imaging device 10 is made of metal such as stainless steel, copper, and aluminum, and the surface of the casing is smoothed by electrolytic polishing to reduce the surface area, and dirt and oxide film are removed to expose the background. And the release of adsorbed gas molecules and gases (helium, hydrogen, etc.) in the material by vacuum degassing process, the gas release rate after 10 hours at room temperature exhaust in the gas release rate measurement by the throughput method. Is 2×10 ^-7 (Pa·m ³ /sm ² ) or less, or the gas release rate after baking at a temperature of 120°C for 6 hours is 1×10 ^-9 (Pa·m ³ /sm ² ) or less By processing so that the gas release rate is extremely low, it is possible not only to shoot in a vacuum container with a low degree of vacuum but also to shoot in a high-vacuum or ultra-high-vacuum space. Thus, it is possible to provide the imaging device 10 which does not release the impurity gas into the vacuum space and can be used even in a high-vacuum or ultra-high-vacuum vacuum container which cannot be used conventionally.

In this image pickup apparatus 10, a lens 32 provided in a camera module 31 such as a CCD camera module or a CMOS camera module is used as a light guide member for the image pickup element, and a light receiving surface of the lens 32 faces the sealing body 29. With the configuration in which the module 31 is housed in the housing space 23, the inside of the vacuum container 50 can be directly photographed by the camera module 31, and high-resolution photographing can be performed, and image processing such as digital zoom and autofocus is easy. Is.

On the other hand, in the configuration in which the fiberscope 33 is provided as a light guide member for the image pickup element, the tip portion 33a of the fiberscope 33 is arranged in the housing space 23 inside the casing 20 so as to face the sealing body 29, and at the same time, the casing 20 In the configuration in which the other end of the fiberscope 33 extending outside is arranged so as to face the image sensor (camera module 31), the image observed through the fiberscope 33 is captured, so the resolution of the image is Although the temperature may decrease, the camera module 31 with a restriction on the operating temperature range can be arranged outside the vacuum container 50, and therefore, compared to the case where the camera module 31 is arranged inside the casing 20, and thus inside the vacuum container 50, more. It is possible to take an image even in the high or low temperature vacuum container 50.

Further, as described above, in the configuration in which the camera module 31 such as the CCD camera module or the CMOS camera module is housed in the casing 20, a wireless device (not shown) that wirelessly outputs the image data generated by the camera module 31 is used. By housing the camera module 31 and a battery (not shown) for driving the radio in the housing space 23 of the casing 20, it is not necessary to provide wiring extending inside and outside the casing 20, and Since the module 31 and the wireless device for short-distance communication (for example, “Bluetooth” (registered trademark)) can be operated for a relatively long time even when driven by a battery, the inside of the vacuum container 50 is observed for a long time. It is also possible.

In addition, when the output of the image data generated by the camera module 31 and the power supply to the camera module 31 are performed by a cable, when the USB cable 34 is adopted as this cable, the other end of the casing 20 is connected to the outside of the vacuum container 50. By connecting the USB cable 34 extended to the personal computer to a personal computer (not shown), the personal computer can be used as a display unit and a recording unit of the image photographed by the camera module 31, and a separate power source is provided. Instead, a personal computer can be used as a power source for the camera module 31.

The casing 20 is configured to include a neck portion 21 provided on the flange 24 side and a head portion 22 provided on the tip end side of the neck portion 21, and the accommodation space 23 is formed in the head portion 22. In addition, in the configuration in which the neck portion 21 is formed of a flexible tube, the position and orientation of the head portion 22 can be freely changed by deforming the neck portion 21 formed of the flexible tube, and a neck made of a flexible tube is also provided. Since the portion 21 has a shape-retaining property, the posture of the head portion 22 can be maintained at the position before and after the change.

In this case, by providing the operating knob 61 provided outside the vacuum container 50 and the swinging mechanism 60 including the connecting member 62 that connects the operating knob 61 and the head portion 22, it is possible to operate the operating knob 61. The direction and position of the head portion 22 can be changed from outside the vacuum container 50.

The connecting member 62 of the swing mechanism 60 may be configured by providing a wire, a connecting rod, or the like, but by using a commercially available wobble stick as the swing mechanism 60, the swing mechanism 60 60 could be provided relatively easily.

In the configuration in which the attachment 40 detachably attached to the one end 20a of the casing 20 is provided and the attachment protection body 41 is detachably attached to the front of the sealing body 29 by the attachment 40, vapor deposition is performed on the attachment protection body. While the sealing body 29 can be prevented from being soiled by adhering an object, when the anti-adhesion protection body 41 is contaminated, it can be easily replaced by attaching and detaching the attachment 40.

Furthermore, in the structure in which the casing 20 is provided with the heat shield layer, even if the temperature in the vacuum container 50 is high or low, the equipment housed in the casing 20 is protected from heat. I was able to.

In the imaging device provided with the cooling structure 70 for cooling the camera module 31 housed in the housing space 23, the camera module can be suitably protected from heat received during baking, etc. It could be used in a higher temperature environment.

(A) is a left side view, (B) is a front view, (C) is a right side view of the imaging device of this invention. II-II sectional view taken on the line of FIG. 1(B). (A) is a left side view of another image pickup apparatus of the present invention having a cooling structure, (B) is a front cross-sectional view of one end side, (C) is a front cross-sectional view with the cooling structure removed, (D). Is the right side view. (A) is a left side view, (B) is a front sectional view, and (C) is a right side view of an image pickup apparatus of the present invention having another cooling structure. The partial cross section front view of another imaging device of this invention. The front view of the imaging device of the present invention provided with the rocking mechanism. The front view of the imaging device of the present invention which shows the example of change of the formation position of a window. It is an expanded sectional view of the tip of a casing (head part), (A) shows an example of sealing using an O ring, and (B) shows an example of sealing using a metal seal. Explanatory drawing of the measuring device used for measurement of a gas release rate. The graph of the measurement result of a gas release rate. Explanatory drawing of the conventional imaging device (it corresponds to FIG. 1 of patent document 1).

1 and 2 show an embodiment of the image pickup apparatus 10 of the present invention.

The image pickup device 10 includes an image pickup device (not shown) such as a CCD sensor or a CMOS sensor, and the photoelectric conversion function of the image pickup device converts light (image) into image data which is an electric signal and outputs the image data. Of the mechanism 30 and the light guide member (member that transmits received light and emits it to the image pickup device) provided in the image pickup mechanism 30, at least a light receiving portion that receives light is stored in the vacuum container 50. A casing 20 for inserting and arranging in a vacuum container 50 is provided while maintaining a vacuum.

The casing 20 has a window 28 sealed on one end 20a side with a sealing body 29 formed of a translucent material such as glass or sapphire (glass in this embodiment), and is housed inside the window 28. A space 23 is formed, and a flange 24 projecting in the direction orthogonal to the longitudinal direction is provided on the other end 20b side.

Then, with one end 20a side (the side where the window 28 is formed) of the casing 20 facing inward, an opening 52 (see FIG. 2) formed in the wall surface 51 of the vacuum container 50 is provided inside the vacuum container 50 from outside the vacuum container 50. The casing 20 is inserted through the casing 20, and the flange 24 is attached to the fixing flange 54 attached to the opening 52 to seal the opening 52, so that the casing 20 is vacuum-tight while maintaining the airtightness of the vacuum container 50. It is configured so that it can be arranged in 50.

In the embodiment shown in FIGS. 1 and 2, the above-described image pickup mechanism 30 is arranged on an image pickup device such as a CCD sensor or a CMOS sensor and components necessary for image pickup by this image pickup device, for example, in front of the image pickup device. A sealing body configured by a camera module 31 in which an AD converter for converting an output signal of a lens and an image pickup device into a digital signal is modularized, and a lens 32 provided in the camera module 31 seals a window 28. By accommodating the camera module 31 in the accommodating space 23 in a state of being opposed to 29, it is possible to capture an image inside the vacuum container 50.

Therefore, in the configuration shown in FIGS. 1 and 2, the lens 32 provided in the camera module 31 forms a light guide member of the image pickup mechanism 30 that transmits the received light and emits the light to the image pickup element. The light receiving surface serves as the light receiving portion of the light guide member described above.

As shown in FIG. 5, the image pickup mechanism 30 is configured to include a fiberscope 33 as a light guide member in front of the camera module 31, as shown in FIG. 5, instead of the configuration shown in FIGS. 1 and 2. Alternatively, the tip end portion 33a of the fiberscope 33 may be disposed in the housing space 23 formed in the casing 20 as a light receiving portion of the above-described light guide member so as to face the sealing body 29 and the casing 20 The other end of the fiber scope 33 may be extended outside the casing 20 from the other end 20b side (the side where the flange 24 is formed), and the camera module 31 may be arranged facing the other end of the fiber scope 33.

As described with reference to FIGS. 1 and 2, in the configuration in which the camera module 31 is housed in the casing 20, the vacuum container 50 is housed in the casing 20 by housing the camera module 31 capable of high-resolution imaging. While it is possible to take a clear picture of the inside and easily add functions such as digital zoom and autofocus, the usable temperature of the camera module 31 is, for example, about -5°C to 50°C. With this configuration, there is a limit to imaging in a high or low temperature vacuum container.

On the other hand, as shown in FIG. 5, in a configuration in which a fiberscope 33 as a light guide member is provided in addition to the camera module 31 as the image pickup mechanism 30, the image captured by the camera module 31 is an image observed through the fiberscope 33. Therefore, the resolution of the captured image may be reduced, but with this configuration, the camera module 31 having a limited operating temperature range can be arranged outside the vacuum container 50. Even in the vacuum container 50 of higher or lower temperature, it is possible to take an image without damaging the camera module 31.

In addition, as described above, in the configuration in which the camera module 31 having a limited operating temperature range is housed in the housing space 23 of the casing 20, in order to protect the camera module 31 from heat applied during baking to be described later, The imaging device 10 may be provided with a cooling structure 70 for cooling the camera module 31.

An example of the configuration of the imaging device 10 including such a cooling structure 70 is shown in FIGS. 3 and 4.

The imaging device 10 shown in FIG. 3 includes, as the cooling structure 70 described above, a cooling block 71 formed of a metal having a high heat conductivity such as copper or aluminum and having a coolant passage formed therein, and the cooling block 71. A cooling medium introduction pipe 72 communicating with the cooling medium inlet provided and a cooling medium discharge pipe 73 communicating with the cooling medium outlet provided in the cooling block 71 are provided.

The cooling block 71 described above is housed in the housing space 23 of the casing 20, and the cooling block 71 covers the outer periphery of the tip end portion of the camera module 31 and the shooting light 36 housed in the housing space 23. The above-mentioned refrigerant introduction pipe 72 and refrigerant discharge pipe 73 for introducing and discharging the refrigerant to and from the cooling block 71 are extended from the other end 20b of the casing 20 to the outside of the casing 20, and thus to the outside of the vacuum container 50.

By including the cooling structure 70 configured as described above, in the imaging device 10 shown in FIG. 3, while introducing a coolant such as cooling water from the outside of the vacuum container 50 into the cooling block 71 through the coolant introduction pipe 72. By discharging the refrigerant that has passed through the cooling block 71 through the refrigerant discharge pipe 73, the camera module 31 and the photographing light 36 can be protected from the heat during baking, and the occurrence of a failure due to heat can be prevented. It can be prevented appropriately.

In the camera module 31 thus cooled, a temperature detecting means 74 such as a K-type thermocouple for detecting the temperature of the camera module 31 is arranged in contact with the camera module 31, and the temperature is detected. By allowing the detection signal of the means 74 to be received outside the vacuum container 50, the temperature of the camera module 31 can be monitored.

In addition, in the imaging device 10 described with reference to FIG. 3, the configuration in which the camera module 31 is cooled by the water cooling type cooling mechanism has been described, but the cooling of the camera module 31 is not limited to the cooling by water cooling, and other It may be cooled by the refrigerant.

FIG. 4 shows a configuration example of the image pickup apparatus 10 including the air-cooling type cooling structure 70 that cools the camera module 31 by blowing air.

The imaging device 10 shown in FIG. 4 includes a refrigerant gas introduction pipe 75 that opens toward the camera module 31 housed in the housing space 23 of the casing 20, and the refrigerant gas introduction pipe 75 is connected to the other end 20 b of the casing 20. It is extended to the outside of the casing 20, and hence the vacuum container 50, via the.

Further, the other end 20b of the casing 20 is provided with a vent hole 76, and after the refrigerant gas introduced into the casing 20 by the above-mentioned refrigerant gas introducing pipe 75 cools the inside of the casing 20, the vent hole 76 is provided. It is configured to be released to the atmosphere via the.

With such a configuration, in the imaging device 10 shown in FIG. 4, a relatively low temperature refrigerant gas, for example, dry air is introduced into the casing 20 through the refrigerant gas introduction pipe 75 and is blown to the camera module 31. The refrigerant gas introduced into the casing 20 is stored in the storage space 23 by releasing the refrigerant gas to the outside of the casing 20 (outside the vacuum container 50) through the air release hole 76 provided in the other end 20b of the casing 20. The camera module 31 and the photographing light (not shown) can be cooled and protected from heat.

Also in the configuration shown in FIG. 4, the temperature detection means 74 such as a thermocouple for measuring the temperature of the camera module 31 may be provided so that the temperature of the camera module 31 can be monitored from outside the vacuum container.

The cooling structure 70 described above may be used to heat the camera unit 31 and the photographing light 36 to the operating temperature range of these devices when the imaging device 10 of the present invention is used in a low temperature environment. it can.

In addition, as shown in FIGS. 1 to 4, in the configuration in which the camera module 31 is housed in the housing space 23 formed in the casing 20, as shown in FIGS. Alternatively, a cable 34 for outputting image data converted into an electric signal by photoelectric conversion by the image pickup device of the camera module 31 is connected to the housing space 23 through a hollow space 25 formed in the casing 20. The casing 20 may be extended from the other end 20b side to the outside.

In the illustrated embodiment, a USB cable is used as such a cable 34, and the end portion of the USB cable 34 extended outside the casing 20 is a personal computer in which predetermined software is installed in advance. By connecting the personal computer to a computer (not shown), the personal computer can be used as a display device or a recording device for an image captured by the imaging device 10 of the present invention, and the personal computer can be used as a power source for the camera module 31. It is possible to do so, and it is not necessary to secure a separate power supply.

It should be noted that, as shown in FIGS. 1 to 4, instead of the wired connection using the USB cable 34, although not shown, in the housing space 23 formed in the casing 20, together with the camera module 31, for example, "Bluetooth. , Etc. and a battery (not shown) for driving the camera module 31 and the wireless communication unit (not shown), and the USB cable 34 described above is not provided. It may be configured.

As described above, even when the camera module 31 and the wireless communication unit are driven by the battery housed in the housing space 23 formed in the casing 20, the camera module 31 is used as a mobile phone, for example. In addition to the existing CMOS camera module and the wireless communication unit for short-range communication such as "Bluetooth" mentioned above, it can be driven for a relatively long time even when it is driven by a battery. It is possible to monitor the inside of the vacuum container 50 for a long time.

The above-mentioned casing 20 adopts a cylindrical configuration having a substantially constant diameter as a whole except for the portion where the flange 24 is formed, as shown in FIG. 5, for the purpose of not requiring a variable shooting direction. However, as shown in FIGS. 1 to 4, it is preferable that the photographing direction is variable.

In the embodiment shown in FIGS. 1 to 4, the casing 20 has a neck portion 21 formed on the side where the flange 24 is formed and a head portion formed on the tip side of the neck portion 21 in order to make the photographing direction variable. The neck portion 21 is divided into 22, and the neck portion 21 is formed by a flexible tube made of stainless steel.

With this configuration, it is possible to change the orientation of the head portion 22 by appropriately deforming the neck portion 21 appropriately, and to maintain the posture after deformation by the shape retention of the metal flexible tube, It is possible for the head portion 22 to maintain the changed orientation.

In addition, in the configuration shown in FIGS. 1 and 2, the neck portion 21 is formed to have a smaller diameter than the head portion 22. However, the weight of the head portion 22 is heavy and the flexible tube having a small diameter is used. When it is difficult to maintain the posture, for example, when the neck portion 21 is formed with the head portion 22, the posture changes due to the weight of the head portion 22, and as shown in FIGS. The diameter of the flexible tube to be used may be expanded to the same extent as that of the head portion 22, and further, the neck portion 21 has a double tube structure in which a small diameter flexible tube is inserted into a large diameter flexible tube. You may increase shape power.

In addition, in the embodiment shown in FIGS. 1 to 4, a configuration is employed in which one end 20a of the casing 20 is provided with a window 28 that opens in the longitudinal direction of the casing 20, but this window 28 is For example, as shown in FIG. 7, the casing 20 may be opened in a direction orthogonal to the longitudinal direction, and the formation position of the window 28 can be appropriately changed according to the application.

The sealing body 29 for sealing the window 28 is a method capable of maintaining the airtightness of the vacuum container 50 without connecting the accommodation space 23 formed in the casing 20 and the space inside the vacuum container 50. Install.

As such a method, in the embodiment shown in FIGS. 1 and 2, as shown in FIG. 8A, a sealing body 29 for sealing the window 28 and a front surface of the sealing body 29 are provided. To prevent the sealing body 29 from being contaminated by vapor deposition or the like when disposed, the deposition-preventing protection body 41 formed of a translucent material (glass in this embodiment) such as glass or sapphire is provided in the casing 20. Adopting a structure in which the attachment 40 attached to one end and a sealing body fixing ring 43 housed inside thereof are detachably attached, not only sealing the window 28 by the sealing body 29, but also the anti-adhesion protection body 41. This makes it possible to protect the sealing body 29 and prevent it from becoming dirty.

Either one or both of the sealing body 29 and the anti-adhesion protection body 41 may be made of lead glass. With this configuration, the X-ray inspection performed in the vacuum container is performed. Even when an image of the situation such as the above is taken, the lead glass serves as an X-ray filter to prevent the generation of noise or damage to the image pickup element that may be caused by the incident X-rays on the solid-state image pickup element. You can

In order to allow the window 28 to be sealed by the sealing body 29, in the embodiment shown in FIG. 8A, a cylindrical portion 28b protruding forward from the outer periphery of the opening edge 28a of the window 28 is provided. After inserting the O-ring 42 and the sealing body 29 into the 28b, the female screw formed on the inner circumference of the cylindrical portion 28b is screwed with the male screw formed on the outer circumference of the sealing body fixing ring 43 to seal. By fixing the stopper body fixing ring 43 in the cylindrical portion 28b, the window 28 can be sealed by the sealing body 29.

Further, the attachment 40 described above is formed into a cylindrical shape as a whole as shown in FIG. 8(A), and an attachment protection body 41 is attached to a flange 40a protruding toward the inner peripheral side at one end side. By inserting the head portion 22 of the casing 20 into the attachment 40 and screwing the male screw 26 formed on the outer periphery of the head portion 22 and the female screw formed on the inner periphery of the attachment 40, The attachment 40 is configured to be detachably attached to one end side, and the front of the sealing body 29 can be covered by the attachment protection body 41 by mounting the attachment 40. ..

With this configuration, vapor deposition on the sealing body 29 that seals the window 28 can be suppressed by the deposition protection body 41, while the deposition protection body 41 contaminated by vapor deposition or the like can be attached to or detached from the attachment 40. Since it can be easily replaced by, it is possible to suitably prevent the inside of the vacuum container 50 from being unable to be imaged due to vapor deposition.

The O-ring 42 sandwiched between the sealing body 29 and the opening edge 28a of the window 28 does not become a source of impurity gas even when it is arranged in a space of high vacuum or ultra-high vacuum. It is possible to use those that have been degassed in advance.

The sealing of the window 28 by the sealing body 29 is less likely to be a source of generation of impurity gas than the sealing through the O-ring described above, and brazing with metal or low melting point glass (melting point about 400 to 500° C.) Sealing by welding may be performed.

Further, in the embodiment shown in FIG. 3, the structure shown in FIG. 8B is adopted as a method of sealing the window 28.

In the configuration shown in FIG. 8(B), the viewing port of the viewing port flange (ICF flange) 45 is the window 28 described above, and the viewing port 28 is preliminarily provided with metal brazing, low melting point glass, or the like. Thin film of soft metal (for example, Au or Al) that has a microcrystalline structure such as surface activation bonding that is performed by welding or activating the surfaces of the bonding parts in vacuum and then stacking them. After film formation, the sealing body 29 made of glass, sapphire, or the like is sealed by room temperature bonding such as atomic diffusion bonding performed by stacking.

The flange 45 with the viewing port to which the sealing body 29 is attached in this manner is attached to the head portion 22 of the casing 20 through the metal seal 48 such as a metal gasket or a helicopter, to the vacuum bolt 46 and the vacuum washer. By using 47, the airtightness can be improved and the generation of impurity gas from the sealed portion can be reduced as compared with the sealing by the O-ring 42 described with reference to FIG. Therefore, it can withstand use in a higher vacuum space.

As in the imaging device 10 described with reference to FIGS. 1 to 4, in the configuration in which the neck portion 21 of the casing 20 is formed of a flexible tube and the orientation of the head portion 22 is variable, the head is exposed from outside the vacuum container 50. A swinging mechanism 60 capable of swinging the portion 22 to change its direction may be further provided (see FIG. 6).

The swinging mechanism 60 includes an operating knob 61 provided outside the vacuum container 50 and a connecting member 62 such as a wire or a connecting rod for connecting the operating knob 61 and the head portion 22. By operating the operation knob 61 outside, the posture of the head portion 22 of the casing 20 can be changed according to the operation of the operation knob 61.

The swing mechanism 60 may be configured by using a commercially available wobble stick as shown in FIG.

In the configuration shown in FIG. 6, a flange 63, an operation knob 61 which penetrates the flange 63 and swings around the penetrating portion of the flange 63 as a fulcrum, and a connecting rod 62 formed continuously with the operation knob 62 are provided. A bullstick is provided as the swinging mechanism 60, and the tip of the connecting rod 62 is attached to the stay 64 attached to the head portion 22 of the casing 20 to swing the operation knob 61. The head portion 22 of the casing 20 can be changed in direction.

As described above, the photographing light 36 may be provided inside the window 28 in the accommodation space 23. In the present embodiment shown in FIG. 7, an LED light is used as the photographing light 36. doing.

As shown in FIG. 3, the photographing light 36 may be configured by an optical fiber having one end opposed to the sealing body 29 and the other end extending from the other end 20b of the casing 20 to the outside. The light from the light source provided outside the casing 20 (outside the vacuum container 50) via the optical fiber may be irradiated from the tip of the optical fiber.

When the image pickup device 10 is used for photographing inside the vacuum container 50 which has been set to a high temperature or a low temperature, in addition to the cooling structure 70 described with reference to FIGS. The other end 20b is provided with a cooling air (or warm air) guiding/discharging port for adjusting the temperature inside the casing 20, and at the same time, cooling air (or warm air) is guided/discharging, thereby The temperature may be maintained, for example, in the operating temperature range of the camera module 31.

Also, instead of or in addition to this configuration, the casing 20 may be surrounded by a heat blocking layer made of a metal cover such as stainless steel or gold to protect the equipment housed in the casing 20 from heat. good.

In the image pickup apparatus 10 of the present invention configured as described above, the outer surface of the casing 20 does not become a source of generation of impurity gas even when it is placed in a space of high vacuum or ultrahigh vacuum. By removing the residual gas by vacuum degassing process while smoothing the surface by electrolytic polishing, the gas release rate after room temperature evacuation 10 hours in the gas release rate measurement by the throughput method is 2×10 ⁻⁷ (Pa·m ³ /sm ² ) or less, or the gas release rate after baking at a temperature of 120° C. for 6 hours is 1×10 ⁻⁹ (Pa·m ³ /sm ² ) or less.

In the present embodiment, the casing 20 described above is formed of SUS304, which is austenitic stainless steel, and electrolytic polishing and vacuum degassing treatment are performed under the conditions described below to obtain the low gas release rate as described above. Has been realized.

Electrolytic polishing Electrochemical polishing is performed by immersing the casing 20 and a counter electrode in an electrolytic solution, flowing a direct current through the electrolytic solution with the casing 20 as a positive electrode and the counter electrode as a negative electrode, and thereby chemically dissolving the surface of the casing 20. This is a simple polishing method. By doing so, cracks, pinholes, and other fine irregularities formed on the surface of the casing by a physical polishing method such as buffing are removed to form a smooth surface. The surface area is reduced to form a surface on which impurities hardly adhere. In the case where the surface of the casing 20 has rough irregularities, the surface is preliminarily polished and adjusted by physical polishing such as buffing using abrasive grains of about #300 to 1000 before electrolytic polishing. Also good.

In the present embodiment, electrolytic polishing using a phosphoric acid-based electrolytic solution is performed under the following conditions, and the surface of the casing is polished until the surface roughness Ra is 0.4 to 0.8 μm. did.
Condition of casing surface before electrolytic polishing: buffing #400, surface roughness Ra 0.4 to 0.8 μm
Electrolyte temperature 40-85 ℃
Voltage 3-10V
Energizing time 3 to 10 minutes

After the electrolytic polishing as described above, the casing was washed with washing water to remove the residual electrolytic solution and the like, and then subjected to the vacuum degassing treatment described later.

Vacuum degassing process The vacuum degassing process is a process of releasing (desorbing) the adhering gas remaining on the surface of the casing by placing the casing in vacuum.

Furthermore, when stainless steel such as SUS304 or SUS316L, preferably SUS316L is used by processing in a high temperature environment of 300°C or higher, Cr and Ni are deposited by heating and a passivation film of chromium oxide is formed. Can also reduce gas emissions.

In this embodiment, the vacuum degassing process was performed under the following conditions.
Pressure in vacuum vessel 10 ^-4 Pa or less (when heating), 10 ^-7 or less (at room temperature)
Heating temperature 300℃
Heating time 24-72h

Gas Release Rate and Measuring Method Therefor As described above, the gas release rate of the casing 20 is measured by performing the electrolytic polishing process and the vacuum degassing process. Rate is 2×10 ⁻⁷ (Pa·m ³ /sm ² ) or less, or 1×10 ⁻⁹ (Pa·m ³ /sm ² ) as the gas release rate after baking treatment at a temperature of 120° C. for 6 hours. I was able to:

Here, the measurement of the gas release rate by the throughput method was performed using a vacuum container in which the sample side chamber and the pump side chamber were connected via an orifice as shown in FIG. 9, and was provided in the pump side chamber. The differential pressure of the vacuum degree between the two chambers when the pump side chamber and the sample chamber are evacuated via the pump, when the measurement sample (casing in this case) is placed in the sample chamber, and when the measurement sample is placed The difference between the pressure change when the measurement sample is not placed and the pressure change when the sample is present is measured as the gas flow rate released from the measurement sample.

FIG. 10 shows a graph of the measurement result of the gas release rate of the casing 20 measured by this throughput method.

In the graph of FIG. 10, “(1)” indicates the gas release rate of the casing of the image pickup apparatus of the present invention that has been electropolished and vacuum degassed under the above-described conditions, and “(2)” indicates the electrolysis under the same conditions. The gas release rate of the casing that was only polished, “(3)” is the gas release rate of the casing that was only degreased and washed, and “(4)” is the temperature change of the measurement sample (the casing of the imaging device). ..

From the graph of FIG. 10, in the casing only subjected to electrolytic polishing [graph (2)] and the casing only subjected to degreasing cleaning [graph (3)], the gas release rate after 10 hours at room temperature (10 hours) was It is about 1×10 ⁻⁶ (Pa·m ³ /sm ² ), which is the gas release rate of the casing [graph (1)] of the present invention that has been subjected to both electrolytic polishing and vacuum degassing treatment, 2×10 ^−7. (Pa·m ³ /sm ² ) is significantly exceeded, and it was confirmed that the amount of gas released was significantly reduced in the casing of the present invention.

As described above, in the image pickup apparatus of the present invention, gas release is suppressed, and it is possible to cope with high vacuum or ultra high vacuum.

In the case of the casing of the present invention [graph (1)] that has undergone electrolytic polishing and vacuum degassing, the gas release rate has already reached 6 hours (30 hours) after reaching the temperature of 120° C. after the start of baking. In the casing [Graph (3)], which was only degreased and washed, the baking was completed at 120°C for 24 hours, whereas the detection sensitivity was reduced to below the detection sensitivity (1 x 10 ^-9 Pa·m ³ /sm ² or less). Even after (44h), during the measurement period, the release of the gas was detected all the time, and it was not possible to eliminate the release of the impurity gas by baking (less than the detection sensitivity).

Also, in the case of the casing (graph (2)) only subjected to electrolytic polishing, although the gas release rate could be reduced to below the detection sensitivity (1×10 ⁻⁹ Pa·m ³ /sm ² or less) by baking, After baking at 120°C for 24 hours (44h), and after a lapse of time (50h), the gas release rate below the detection sensitivity (1×10 ^-9 Pa·m ³ /sm ² or less) was finally obtained. It was confirmed that it takes a long time to reduce the release rate of the impurity gas as compared with the casing of the present invention [graph (1)].

Thus, in the image pickup apparatus 10 of the present invention, baking is performed at a relatively low temperature of about 120° C. that does not destroy the camera module and the like, and at a relatively short time of about 6 hours, if necessary, so that the impurity gas is not consumed. It is possible to suppress the occurrence of the above in a very low range below the detection sensitivity (1×10 ⁻⁹ Pa·m ³ /sm ² or less).

10 Imaging Device 20 Casing 20a One End (of Casing)
20b The other end (of the casing)
21 neck part 22 head part 23 accommodation space 24 flange 25 hollow space 26 male screw 28 window (or viewing port)
28a Opening edge (of window)
28b Cylindrical part 29 Sealing body 30 Imaging mechanism 31 Camera module 32 Lens 33 Fiberscope 33a Tip part (of fiberscope)
34 cable (USB cable)
36 Shooting light 40 Attachment 40a Flange (of attachment)
41 Anti-Protection Body 42 O-ring 43 Sealing Body Fixing Ring 44 Female Screw 45 Flange with Viewing Port 46 Vacuum Bolt 47 Vacuum Washer 48 Metal Seal 50 Vacuum Vessel 51 Wall Surface (Vacuum Vessel)
52 opening 54 fixing flange 60 swinging mechanism 61 operation knob 62 connecting member (connecting rod)
63 flange 64 stay 70 cooling structure 71 cooling block 72 refrigerant introduction pipe 73 refrigerant discharge pipe 74 temperature detection means 75 refrigerant gas introduction pipe 76 vent hole 100 image pickup device 102 object to be treated 103 vacuum container 104 closed container 110 imaging mechanism 111 lens 115 recording Circuit part 116 Display device 125 Lead wire

Claims (14)

An imaging device used for imaging in a vacuum container, comprising an imaging mechanism including an imaging element, and a casing for accommodating at least a part of the imaging mechanism and arranged in a vacuum container,
The casing includes a window formed at one end side, a sealing body made of a translucent material for sealing the window, a housing space formed inside the window, and a flange provided at the other end side. Prepare,
By inserting the one end side of the casing into the vacuum container, inserting the casing from the outside of the vacuum container into the opening formed in the wall surface of the vacuum container, and sealing the opening with the flange from the outside of the vacuum container. , While maintaining the airtightness of the vacuum container, the casing can be arranged in the vacuum container,
The imaging mechanism includes a light guide member that transmits received light and emits the light toward the image sensor, and a light receiving portion of the light guide member is housed in the housing space so as to face the sealing body. Therefore, the inside of the vacuum container can be photographed,
Said casing is made of stainless steel, an outer surface roughness is polished until the 0.4~0.8μm in Ra, the vacuum degassing treatment with the electrolytic polishing, heat above 300 ° C., by throughput method in outgassing rate after room temperature exhaust 10 hours in outgassing rate measurement ^{2 × 10 -7 (Pa · m} 3 / sm 2) below, and detected outgassing rate after 6 hours baked at a temperature of 120 ° C. An imaging device for a vacuum container, which is formed to have a sensitivity of 1×10 ⁻⁹ (Pa·m ³ /sm ² ) or less. The imaging mechanism is composed of a camera module,
The camera module is housed in the housing space, with a light receiving surface of a lens provided in the camera module facing the sealing body as the light receiving portion of the light guide member of the imaging mechanism. An imaging device for a vacuum container according to claim 1. A wireless device capable of wirelessly outputting image data generated by the camera module, and a drive battery for driving the camera module and the wireless device are housed in the housing space of the casing. Item 2. An imaging device for a vacuum container according to item 2. One end of a USB cable capable of outputting image data generated by the camera module and capable of supplying driving power to the camera module is connected to the camera module, and the other end of the USB cable is connected to the casing. The imaging device for a vacuum container according to claim 2, wherein the imaging device extends from the other end to the outside of the casing. The imaging mechanism includes a fiberscope as the light guide member,
The tip end of the fiberscope is arranged as the light receiving portion so as to face the sealing body in the housing space inside the casing, and the other end of the fiberscope extends outside the casing from the other end of the casing. The image pickup device for a vacuum container according to claim 1, wherein the image pickup device is provided on a front surface of an image pickup element arranged outside the casing. The casing includes a neck portion formed on the flange side and a head portion provided on the tip side of the neck portion,
The imaging device for a vacuum container according to claim 1, wherein the accommodation space is formed in the head portion and the neck portion is formed of a flexible tube. An operation knob provided outside the vacuum container,
A connecting member having one end connected to the head portion and the other end connected to the operation knob;
7. The image pickup apparatus for a vacuum container according to claim 6, further comprising a swinging mechanism that swings the head portion by operating the operation knob. The imaging device for a vacuum container according to claim 7, wherein the connecting member is a wire. The image pickup apparatus for a vacuum container according to claim 7, wherein the swing mechanism is a wobble stick. An attachment detachably attached to the one end of the casing is provided, and an attachment preventive body made of a translucent material is detachably attached to the front of the sealing body by the attachment. The imaging device for a vacuum container according to claim 1. The imaging device for a vacuum container according to claim 1, further comprising a heat shield layer provided on an outer periphery of the casing. The imaging device for a vacuum container according to claim 2, further comprising a cooling structure that cools the camera module housed in the housing space. The cooling structure communicates with a cooling block that covers the camera module in the accommodation space, a refrigerant introduction pipe that communicates with an inlet of a refrigerant passage provided in the cooling block, and an outlet of the refrigerant passage. The imaging device for a vacuum container according to claim 12, further comprising a refrigerant discharge pipe, wherein the refrigerant introduction pipe and the refrigerant discharge pipe are extended from the other end of the casing to the outside of the vacuum container. .. The cooling structure has a refrigerant gas introduction pipe having one end opened toward the camera module in the accommodation space and the other end extending outside the vacuum container from the other end of the casing; and the other of the casing. 13. The image pickup apparatus for a vacuum container according to claim 12, further comprising an air vent hole provided at an end for venting gas inside the casing to the outside of the vacuum container.

Images