JP2007274288A - Cooling container for imaging element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling container for an imaging element which can easily cool imaging element (image sensor), prevent dew condensation of a transparent plate on the subject side or in the container, and cope with wide-ranging applications. <P>SOLUTION: This cooling container for an imaging element comprises a metallic external container 8, having a window opening and a bottom opening smaller than the window opening on its bottom surface; a container bottom 12 in which a group of conductive terminals 11 and a thermally conductive support member thermally, coupled to an imaging element 14 on its one end and to a heat-absorbing portion of a cooler on the other end are supported hermetically, so that one ends of the conductive terminals 11 appear in the inside and the other ends appear in the outside of the container, and one ends of the thermally conductive supporting member (metal rod 13) appear in the inside of the container and the other ends appear in the outside of the container, and which is hermetically coupled to the bottom opening of the external container 8; an inside container 10 surrounding a space 15 at the center of the external container 8, to form a thermally insulated space 9 between the external container 8 and an internal peripheral wall; and double glass window assemblies (5, 3, 7) in close contact with the window opening that are replaceable. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging element cooling container in which an imaging element (image sensor) is accommodated in a container having a transparent window and can be operated in a cooled state.

  In high-sensitivity CCD imaging, element cooling is indispensable, and the CCD imaging element is cooled. However, when the temperature is lowered, moisture in the atmosphere is condensed, and the light receiving surface is cloudy, and imaging cannot be performed. In order to solve these problems, a method of flowing a dry gas around the image sensor or storing it in a vacuum container is generally employed (Patent Documents 1 to 3). In the method of flowing gas, in order not to cause dew condensation, an apparatus for producing dry air having a dew point temperature equal to or lower than the cooling temperature becomes large, and it is necessary to purchase gas, resulting in an increase in running cost.

On the other hand, the method of storing the CCD in the vacuum vessel does not incur a running cost, but because different materials such as glass and metal are joined, if the structure and manufacturing accuracy are poor, the effect of temperature changes such as cooling during use and normal temperature after use. Etc., distortion is likely to occur, the degree of vacuum gradually decreases, and the heat insulation effect also decreases. In such a case, it is necessary to evacuate again to cause condensation. Further, when the internal element is destroyed, the entire container cannot be used.
Japanese Patent Laid-Open No. 7-7668 JP-A-8-205007 JP 2002-40554 A

An object of the present invention is to provide an imaging device cooling container that is inexpensive and easy to maintain, that it can respond to different demands of various imaging devices, and that the cost required for maintenance can be minimized.
An object of the present invention is to introduce a combination of new configurations, so that an image sensor such as an image sensor can be easily cooled, and condensation on a transparent plate in a subject side or a container can be prevented. An object of the present invention is to provide an imaging element cooling container that can be applied to applications.

In order to achieve the object, an imaging element cooling container according to claim 1 according to the present invention is provided.
A metallic outer container having a window opening and a bottom opening on the bottom;
The conductive terminal group and a thermally conductive support member thermally coupled to the image sensor at one end and the heat absorbing portion of the cooling device at the other end, the one end side of the conductive terminal group inside the container and the other end outside the container, the thermal conductivity A container bottom that supports one end of the support member in an airtight manner so that the other end appears outside the container and is airtightly coupled to the bottom opening of the outer container;
An inner container that surrounds a central space of the outer container and forms a heat insulating space between inner peripheral walls of the outer container;
A glass window assembly that is exchangeably attached to the window opening.

The imaging device cooling container according to claim 2 according to the present invention is the imaging device cooling container according to claim 1,
The imaging device can be a CCD or CMOS image sensor,
The heat absorption part of the cooling device can be a heat absorption part of a Peltier element,
The heat insulating space between the inner container surrounding the central space of the container and the inner peripheral wall of the outer container can be a vacuum space,
The window portion of the glass window assembly may be a double glass window assembly that forms a heat insulating space on the window side.

Since the imaging device cooling container according to the present invention is configured as described above, the following specific effects can be obtained.
A. Since the container according to the present invention does not house the image sensor in the vacuum heat insulating portion, there is no room for problems due to conventional vacuum sealing. The problem of dew condensation in the container is solved, and if a double glazing structure is used, dew condensation on the surface can be prevented.
I. When the space is sealed after the image sensor is attached, it is not necessary to use heat to join the glass and the heat insulating container, so that the element can be prevented from being damaged.
C. Since the pressure difference between the space inside the container and the outside is small, it is possible to reduce entry of undesirable components such as moisture from the outside after sealing.
D. If the container is made to correspond to the socket of the connector and the bottom is prepared for each type of image sensor, it is possible to handle a wide variety of image sensors without designing the container individually.
E. Even if a defect occurs in the image sensor, it can be replaced.

Embodiments of an apparatus according to the present invention will be described below with reference to the drawings.
FIG. 1 is a central sectional view showing an embodiment of an image sensor cooling container according to the present invention. The imaging element cooling container according to the present invention forms a cylindrical or substantially rectangular imaging element and its connection space.
The outer container 8 is obtained by processing aluminum, and has a window opening that opens in the drawing and a bottom opening smaller than the opening at the bottom. The window opening is subjected to a window assembly which will be described later, and an annular groove for receiving an O-ring 4 for keeping airtightness is machined. The bottom opening is an opening that receives a container bottom 12 described later.

The heat conductive support member made of the conductive terminal group 11 and the metal rod 13 such as copper having high heat conductivity is airtightly held by the container bottom 12 made of a material having excellent heat insulation and insulation properties such as foamed styrene. . The container bottom 12 is configured such that the thermally conductive support member (metal rod 13) can be thermally coupled to the back surface of the image sensor 14 at one end and thermally coupled to the heat absorbing unit 16 of the external cooling device at the other end. Further, one end side of the conductive terminal group 11 is supported in the container and the other end appears outside the container, and the bottom opening of the outer container 8 is sealed.
The inner container 10 is an aluminum flanged tubular body, and surrounds the central space 15 of the outer container 8, and forms a heat insulating space 9 between the inner container 10 and the inner peripheral wall of the outer container 8. This insulating space can be evacuated.
A double glass window assembly (5, 5) formed by enclosing a dry gas (air or nitrogen gas) or vacuum space 6 between the optical glass plates 5 and 7 and the glass double glass sealing part 3. 3, 7) is dropped into the upper opening of the outer container 8, and the glass holding plate 2 made of aluminum is hermetically and detachably fixed with a plurality of bolts 1.

Next, an example of assembling the container will be briefly described.
A. The inner container 10 made of an aluminum plate is dropped into the outer container 8 as shown in the figure, attached, and the upper part is joined by welding or brazing.
B. A wax is put on the lower joint portion of the outer container 8 and the inner container 10 and placed in a vacuum furnace to heat and heat-insulating space 9 is sealed in a vacuum.
C. The conductive terminal group 11 and a metal rod 13 such as copper or aluminum having good thermal conductivity are fixed to the container bottom 12 with resin or the like, and the container bottom 12 is hermetically fixed to the opening at the bottom of the outer container.
D. An image sensor 14 such as a CCD or CMOS sensor is fixed to the metal rod 13.
At that time, a metal paste or the like is applied between the image sensor 14 and the metal rod 13 or a metal foil or the like is sandwiched in order to improve heat conduction.
E. Necessary terminals of the conductive terminal group 11 and necessary terminals of the image sensor 14 are electrically connected.

F. A dry gas such as air or nitrogen is introduced into the inner space 6 of the light transmitting portion surrounded by the glass double glass sealing portion 3 between the optical glass plate 5 (outer glass) and the optical glass plate 7 (inner glass). Filling or, in some cases, a vacuum to enhance the heat insulation effect and prevent condensation.
From the relationship between the cooling temperature from the outside of the metal rod 13 and the heat conduction of the gas in the container internal space 15 in which a gas such as dry air or nitrogen is sealed, the two glasses 5 and 7 as shown in FIG. It is not always necessary to have a single glass.
G. In a gas atmosphere such as dry air, a container in which an image sensor up to E is incorporated and the glass of F are sealed with a rubber or resin O-ring 4.
A metal glass retainer 2 and a metal glass retainer bolt 1 are used to seal the container internal space 15 in which a gas such as dry air or nitrogen is enclosed.

  The image pickup device cooling container is provided with a cooling device heat absorption part 16 such as a Peltier element attached to an external portion of the metal rod 13 of the container, cools the image pickup element 14 to a required temperature, and passes through an external optical system (not shown). Thus, the subject can be projected onto the image sensor to capture an image.

Various modifications can be made to the embodiment described in detail within the scope of the present invention. FIG. 2 is a partial cross-sectional view showing a modification of the connection mode of the outer container, the container bottom, and the heat conducting member. In order to strengthen the connection between the outer container and the container bottom, in the case of mass production, uneven grooves are provided on the inner periphery of the outer container 8 and the outer periphery of the heat conducting member 13, respectively, and a resin is poured between them. The container bottom 12 can be formed integrally.
As still another modification, the inner periphery of the outer container 8 and the container bottom 12 can be screwed together, and the container bottom 12 and the heat conducting member 13 can be screwed together. In this case, a certain degree of hermeticity can be maintained only by screw connection, but an adhesive may be applied to improve hermeticity. According to this structure, replacement | exchange of the container bottom part 12 grade | etc., Becomes easy.

  The imaging device cooling container according to the present invention can easily cool the imaging device (image sensor or the like), can prevent condensation on the object side or in the transparent plate in the container, and can correspond to various applications. Therefore, it can be used in the field of evaluation of various image sensors, the acquisition of image data in a poor environment, and the field of measurement.

It is a center sectional view of the example of the image sensor cooling container by the present invention. It is a fragmentary sectional view which shows the modification of the connection aspect of an outer side container, a container bottom part, and a heat conductive member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bolt 2 Glass holding plate 3 Glass double glass sealing part 4 Rubber or resin O-ring 5,7 Optical glass board 6 Dry gas or vacuum space 8 Outer container 9 Thermal insulation space 10 Inner container 11 Conductive terminal 12 Container bottom 13 Heat conduction member (metal bar)
14 Image sensor 15 Container internal space 16 Cooling device heat absorption part

Claims (2)

A metallic outer container having a window opening and a bottom opening on the bottom;
The conductive terminal group and a thermally conductive support member thermally coupled to the image sensor at one end and the heat absorbing portion of the cooling device at the other end, the one end side of the conductive terminal group inside the container and the other end outside the container, the thermal conductivity A container bottom that supports one end of the support member in an airtight manner so that the other end appears outside the container and is airtightly coupled to the bottom opening of the outer container;
An inner container that surrounds a central space of the outer container and forms a heat insulating space between inner peripheral walls of the outer container;
An image sensor cooling container comprising: a glass window assembly that is exchangeably attached to the window opening. The image sensor is a CCD or CMOS image sensor,
The heat absorption part of the cooling device is a heat absorption part of a Peltier element,
The heat insulating space between the inner container surrounding the central space of the container and the inner peripheral wall of the outer container is a vacuum space,
The imaging device cooling container according to claim 1, wherein the window portion of the glass window assembly is a double glass window assembly that forms a heat insulating space on the window side.

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