JP3944446B2 - Digital camera for optical equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera for an optical apparatus suitable for an optical apparatus such as a microscope.
[0002]
[Prior art]
In microscopic observation, high-quality images are required for performing pathological diagnosis in which diagnosis is performed according to cell morphology, fluorescence imaging in which changes in specimens are measured by weak fluorescence, and the like. As a means for obtaining an image, there is a digital camera system using a solid-state image pickup device such as a CCD device (hereinafter referred to as “CCD device”) instead of a conventional camera system using a silver salt film as an image pickup medium. It has come to be used.
[0003]
A CCD element as an imaging medium has a dark current in which a minute output current flows even when there is no light input. The dark current increases depending on the temperature rise and becomes noise to the image signal, and as a result, SN is lowered. For this reason, a method is adopted in which the dark current is reduced by cooling the CCD element to improve the SN of the image signal.
[0004]
However, when the outside of the CCD element is touched with high humidity in the cooled state, the surface of the CCD element is condensed and moisture is attached. As a result, the image deteriorates or the peripheral device malfunctions. For this purpose, a sealed structure is adopted in which the CCD element is arranged in a sealed container with low humidity.
[0005]
The following technique is known as a conventional sealed structure (see Japanese Patent Laid-Open No. 6-45570).
[0006]
That is, this sealed structure is configured as follows. There is no air permeability, and the cable is drawn out from between the sealed containers divided into two using a cable made of a thin film material. And by inserting an O-ring between the cables, the gap is filled and sealed.
[0007]
However, since the above-described sealed structure has to produce a dedicated cable, it is expensive and it is difficult to increase its current capacity.
[0008]
By the way, since the CCD element includes light receiving elements arranged in a two-dimensional manner, the resolution is determined by the total number of light receiving elements. However, if the number of CCD elements is increased by increasing the number of the CCD elements in order to increase the resolution of the light receiving elements, the sensitivity is lowered and the cost is increased.
[0009]
As a means to improve the image quality of the image signal acquired by the CCD element, the CCD element with a small number of pixels is moved two-dimensionally to improve the number of pixels without lowering the sensitivity, thereby improving the image quality. A technique to be realized is disclosed (see Japanese Patent Laid-Open No. 9-21867).
[0010]
In the above technique, a plate-like metal member is bent and a CCD element is assembled to a displacement mechanism using the elastic force. Then, by moving the CCD element two-dimensionally via the displacement mechanism, the number of pixels is improved without reducing the sensitivity.
[0011]
However, no means for reducing the dark current of the CCD element has been proposed as means for improving the image quality of the CCD element.
[0012]
As described above, the conventional sealed structure of the CCD element requires the production of a dedicated connection cable and has a limitation of the substrate configuration due to the current capacity. In addition, the means for improving the image quality of the conventional CCD element is not possible. Although the resolution can be improved, the dark current increases and the SN is lowered.
[0013]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide a digital camera for an optical device that has a simple configuration, can improve the current capacity, and can prevent the occurrence of dark current and promote the enhancement of image quality. And
[0014]
[Means for solving the problems]
A digital camera for an optical apparatus according to the present invention includes a solid-state image sensor for imaging an object, a solid-state image sensor cooling means for cooling the solid-state image sensor , a printed circuit board for electric signal wiring, and the electric signal wiring. The printed circuit board for use constitutes a part of the sealing means for sealing the solid-state image sensor and the solid-state image sensor cooling means.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0016]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0017]
FIG. 1 is a diagram showing a microscope equipped with a digital camera for an optical device according to a first embodiment of the present invention. The microscope main body 201 is provided with a stage 202 that can position the specimen 206 so as to be movable up and down in the optical axis direction. Further, the microscope body 201 is combined with an objective lens 203 for enlarging a specimen image facing the stage 202 and a lens barrel 205 equipped with an imaging lens 207 and an eyepiece lens 204 for visual observation. The A camera main body 208 that constitutes a digital camera for an optical apparatus is disposed downstream of the imaging lens 207.
[0018]
With the above configuration, when acquiring a specimen image, the specimen 206 is placed on the stage 202, the stage 202 is moved up and down, and the specimen is aligned with the focal position of the objective lens 203. Thus, an enlarged image of the specimen can be observed. At the same time, an enlarged image of the specimen is formed on the imaging surface 209a of the CCD element (solid-state imaging element) 209 of the camera body 208 by the imaging lens, and a specimen image is acquired.
[0019]
The camera body 208 includes a lower exterior 106 and an upper exterior 117 as shown in FIG. On the lower exterior 106 constituting the sealed container, a female screw portion 108 for attachment is provided corresponding to a male screw (not shown) provided in the lens barrel 205. The female screw portion 108 is screwed into the male screw of the lens barrel 205 and assembled to the microscope main body 201.
[0020]
The CCD element 209 is mounted by soldering on the CCD element printed board 101 accommodated in the camera body 208. A Peltier element 102 that moves heat by applying a voltage is thermally coupled to the back surface 209b of the CCD element 209 via a thermally conductive elastic member 103 having a high thermal conductivity. The Peltier element 102 is attached to a displacement member 105 described later. The material of the elastic member 103 with high thermal conductivity is not particularly limited. For example, any material can be used as long as it is an elastic member with excellent thermal conductivity such as a high thermal conductive rubber sheet manufactured by Shin-Etsu Silicone Co., Ltd. May be used.
[0021]
A spacer 104 is interposed between the displacement member 105 and the CCD element printed board 101. The spacer is shorter than the length of the Peltier element 102 and the high thermal conductive elastic member 103 by adding the length of the mounting surface 101a of the CCD element printed circuit board 101 and the spacer 104 from the back surface 209b of the CCD element 209. A length of 104 is set. As a result, when the displacement member 105 and the printed board 101 are fixed using the screws 120a, the Peltier element 102 is in a state where the high thermal conductive elastic member 103 is deformed and brought into close contact with the printed board 101 to the displacement member 105. Fixed. Therefore, the thermal resistance between each member is fixed in a low state. The displacement member 105 is fixed to the lower exterior 106 using screws.
[0022]
In addition, a glass member 115 for capturing an image is fixedly arranged in the lower exterior 106 in the female screw portion 108 of the lower exterior 106 via a fixing member 107. In order to enhance the sealing between the glass member 115 and the lower exterior 106, a groove 106 a is formed in the lower exterior 106 so as to face one surface of the glass member 115. An O-ring 110 made of an elastic rubber material is inserted into the groove 106a.
[0023]
The wire diameter of the O-ring 110 is set to be approximately 30% thicker than the depth of the groove 106a. When the O-ring 110 is accommodated in the groove 106a, the O-ring 110 is fixed in a state of being crushed on one surface of the glass member 115. Thereby, since a small gap can be filled, it becomes possible to obtain high sealing performance.
[0024]
Further, the lower exterior 106 is provided with a groove 106 b on the opposite side to the female screw portion 108. An O-ring 112 is inserted into the groove 106b. Then, the inner lid 109 is attached from above the groove 106b. The sizes of the groove 106b and the O-ring 112 are set to the same size as the groove 106a and the O-ring 110, respectively, and are installed so as to have a desired hermeticity as described above. A state in which the cable 111 is connected to the substrate 114 via the inner lid 109 is shown in FIG. FIG. 3 is an exploded perspective view showing a portion A of FIG. 2 in an enlarged manner.
[0025]
As shown in FIG. 3, the inner lid 109 is provided with a rectangular long hole 109a for inserting a cable. Around the long hole 109a, six substrate fixing studs 113 and two positioning studs 301 for positioning the O-ring 302 are fixed at predetermined intervals by welding or the like. Between the positioning studs 301, the O-ring 302 is attached in a stretched state.
[0026]
The height of the studs 113 and 301 and the wire diameter of the O-ring 302 are
The wire diameter of the O-ring 302> the height of the stud 113> the height of the stud 301 is set. As a result, when the control printed board 114 is fixed to the inner lid 109 with the screws 120b, the O-ring 302 is crushed evenly to the height of the stud 113.
[0027]
The control printed circuit board 114 is externally connected to an external personal computer (not shown) via the external connector 118. A surface mount type connector 304 is mounted on the inner surface of the control printed circuit board 114 as shown in FIG. The connector 304 is electrically connected to the CCD element printed board 101 via the cable 111.
[0028]
In the printed circuit board 114 for control, the screw hole 303 corresponds to the stud 113 and is within the contact range of the O-ring 302 (the part surrounded by the broken line A in FIGS. 3 and 4. ) (See FIG. 4), and the screw 120b is screwed and fixed to the stud 113 through the screw hole 303.
[0029]
That is, in the control printed board 114, in addition to the screw hole 303, a through hole 400 for conducting each layer in the multilayer board is formed outside the contact range (broken line A). Further, since the connector 304 used for the control printed circuit board 114 is a surface mounting type as described above, there is no hole in the contact range (broken line A) and there is almost no air permeability. The printed circuit board for control 114 is coated with a resist film made of a resin material on the surface in manufacturing the board. For this reason, even if it is formed of a breathable glass epoxy material, there is no hole passing through the resist film within the contact range (broken line A), which is a range used as a sealed container. Therefore, the printed circuit board 114 functions as a part of the sealed container, and a desired sealed structure is realized.
[0030]
With the above configuration, the CCD element 209, the Peltier element 102, and the high thermal conductive elastic member 103 are composed of the lower exterior 106, the glass member 115, the inner lid 109, the control printed board 114, and the O-rings 110 and 112 that constitute the sealed container. , 302 are sealed from the outside air.
[0031]
A predetermined amount of a desiccant 116 such as silica gel is attached to the inner surface of the inner lid 109 constituting the sealed container. As a result, the moisture taken in during the work and the moisture that enters through a slight gap are dehumidified by the desiccant 116 and the inside of the sealed container is kept at a low humidity. As a result, dew condensation does not occur on the imaging surface 209a of the CCD element 209 without affecting the external humidity, unless it is cooled to a temperature lower than the dew point due to moisture in the sealed container.
[0032]
Further, a part of the hermetic container is constituted by a control printed board 114 having no holes such as through holes. Thereby, it is not necessary to provide a special part such as a conventional flat cable for electrical connection inside and outside the sealed container. Therefore, a large current capacity can be obtained, and various configurations can be adopted.
[0033]
Here, the displacement member 105 will be described. As shown in FIG. 5, the displacement member 105 includes a displacement part 105a, a fixed part 105b, and a hinge part 105c that connects both, and is integrally formed by, for example, a wire cutting method. In two perpendicular directions between the displacement part 105a and the fixed part 105b, the piezo element 500 constituting the displacement means is bonded.
[0034]
The piezo element 500 has the property of being displaced in proportion to the applied voltage. And the displacement part 105a of the displacement member 105 can be displaced by arbitrary amount by controlling an applied voltage via the control part which is not shown in figure. As a result, the CCD element 209 supported by the displacement portion 105 a is controlled to move in two dimensions in conjunction with the displacement of the piezo element 500.
[0035]
Further, a CCD element 209 and a high thermal conductive elastic member 103 are attached to the displacement member 105 by being thermally coupled. As a result, the displacement member 105 transmits the heat moved by the Peltier element 102 to cool the CCD element 209. Then, the heat transmitted by the displacement member 105 is transmitted to the lower exterior 106 and is finally radiated to the outside air. As described above, the heat dissipation path of the Peltier element 102 includes the displacement member 105 and the lower exterior 106. Thereby, it is possible to realize a heat dissipation path with a low thermal resistance by configuring the heat dissipation path only with mechanical coupling with a small number of components.
[0036]
As described above, the digital camera for an optical apparatus according to the present embodiment is a part of a sealed container that seals the CCD element 209 for photographing and the Peltier element 102 constituting the CCD element cooling means for cooling the CCD element 209. Are formed on the control printed circuit board 114.
[0037]
According to this, external connection becomes possible via the printed circuit board 114 for control which comprises a part of airtight container. This eliminates the need for a sealed structure using a dedicated cable as an external connection component as in the prior art. For this reason, a reduction in dark current and prevention of condensation can be realized, and a substrate configuration that is not restricted by current capacity can be realized.
[0038]
In the digital camera for an optical apparatus according to the present embodiment, a CCD element 209 and a displacement member 105 that supports the CCD element 209 so as to be displaceable are configured via a Peltier element 102.
[0039]
Thereby, the heat moved by the Peltier element 102 to cool the CCD element 209 is transmitted to the lower exterior 106 constituting the sealed container via the displacement member 105 and radiated. Thereby, since it is not necessary to newly provide a heat dissipation path for the Peltier element 102, the load on the displacement member can be reduced, and the number of parts can be reduced.
[0040]
In the first embodiment, the case where a part of the hermetic container is configured by the inner lid 109 and the control printed board 114 has been described. However, the present invention is not limited to this, and the control printed board as shown in FIG. It is also possible to configure the sealed container by directly closing the lower exterior at 600. FIG. 6 is a block diagram showing a main part of a digital camera for an optical apparatus according to the second embodiment of the present invention. However, in FIG. 6, for convenience, the same parts as those in FIGS. 1 to 5 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0041]
That is, an O-ring 112 is inserted into the groove 106b of the lower exterior 106, and the control printed circuit board 600 is screwed from above. As a result, the unevenness on the control printed circuit board 600 and the small gap in the lower exterior 106 are sealed in the same manner as in the first embodiment to form a sealed structure.
[0042]
According to the second embodiment, the inner lid 109 and the O-ring 112 in the first embodiment can be omitted. In the second embodiment, the connection between the layers of the printed circuit board 600 for control does not provide a hole penetrating between all the boards. For example, in a four-board structure, a hole penetrating only three is provided. Provided, a conductive member called a buried via is inserted into the hole, and means for conducting three sheets is used.
[0043]
In each of the above-described embodiments, the description has been given of the case where the optical device is applied to a microscope. However, the present invention is not limited to this and can be applied to other optical devices. In the above embodiment, the Peltier element 102 is attached to the displacement member 105. However, if high resolution is not required, the thermal conductivity for simply transferring the heat from the Peltier element 102 to the lower exterior 106 is described. The member may be a metal plate such as aluminum or brass.
[0044]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.
[0045]
A digital camera for an optical device according to an aspect of the present invention includes a solid-state image sensor for imaging an object, a solid-state image sensor cooling means for cooling the solid-state image sensor, and a printed circuit board for electric signal wiring. A sealing means for sealing the solid-state image sensor and the solid-state image sensor cooling means is provided. In addition, it is preferable that the said solid-state image sensor cooling means has a Peltier device and a heat conductive member.
[0046]
Preferred embodiments of the digital camera for an optical device according to one aspect of the present invention are as follows. The following embodiments may be applied independently or may be applied in appropriate combination.
[0047]
(1) An elastic member having a good thermal conductor disposed between the Peltier element and the solid-state imaging element is further provided.
[0048]
(2) The printed circuit board includes a connector for electrical connection, a through hole, and an attachment hole, and the connector is attached to a portion that functions as a lid portion of the sealing means, The attachment hole should be attached to a place other than the portion functioning as the lid of the sealing means.
[0049]
(3) In (2), the exterior includes an inner lid having an opening through which a connector wiring connected to the connector of the printed board passes, and the printed board seals the opening of the inner lid. thing.
[0050]
(4) The sealing means further includes an exterior covering the solid-state image sensor cooling means, and the printed circuit board functions as a lid for sealing the opening of the exterior.
[0051]
(5) In (4), the heat generated in the solid-state imaging device is released to the outside through the elastic member, the Peltier device, the heat conductive member, and the exterior.
[0052]
(6) In (5), the thermally conductive member is a displacement member.
[0053]
(7) In (4), the printed circuit board has a connector for electrical connection, a through hole, and an attachment hole, and the connector is attached to the opening of the exterior, and the through hole and The attachment hole should be attached to a place other than the opening of the exterior.
[0054]
According to the embodiment described above, external connection is possible from the printed circuit board constituting a part of the sealed container, so that a sealed structure using a dedicated cable is not used as a connection component for external connection. Therefore, it is possible to realize a substrate configuration that is not restricted by current capacity while preventing dark current and preventing condensation.
[0055]
According to the above embodiment, the heat generated in the solid-state image sensor by the solid-state image sensor cooling means is dissipated to the outside through the displacement means. Therefore, after improving the resolution, the dark current of the solid-state image sensor is reduced. Mitigation is possible.
[0056]
According to the above embodiment, it is possible to configure a sealing means in which a part is directly closed with a printed circuit board. As a result, the number of parts can be reduced, and the assembly work can be simplified.
[0057]
In addition, for example, even if some structural requirements are deleted from all the structural requirements shown in each embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the effect of the invention Can be obtained as an invention.
[0058]
For example, a digital camera used in an optical device based on the above embodiment, an integrated displacement member having an elastic hinge for finely displacing a CCD element, and a drive for displacing the displacement member by a small amount A printed circuit board comprising: a means; a cooling means for cooling the CCD element; and a sealed container that blocks a cooling part cooled by the cooling means from outside air, wherein a part of the sealed container is made of glass epoxy. It is possible to provide a digital camera for an optical device characterized by comprising
[0059]
In the above-described embodiment, the glass member 115 is fixed to the lower exterior 106 for the purpose of sealing. However, a filter function such as an IR cut filter function is added to the glass member 115 for purposes other than sealing. Is also possible.
[0060]
By doing so, for example, when the function of the IR cut filter is required in the first embodiment, the glass member 115 fixedly disposed on the lower exterior 106 does not have a filter function. Is fixedly arranged in the optical path as a separate optical member. However, since the filter function is integrally added to the glass member itself, it is not necessary to provide a separate optical member, and the configuration is simple. And cost reduction can be realized.
[0061]
【The invention's effect】
As described above in detail, according to the present invention, the image sensor can be cooled efficiently and reliably, the configuration can be simplified, and a configuration that is not restricted by the current capacity is possible, and the generation of dark current is possible. Thus, it is possible to provide a digital camera for an optical apparatus that can promote the enhancement of the image quality.
[Brief description of the drawings]
FIG. 1 is a layout view showing a state in which a digital camera for an optical device according to a first embodiment of the present invention is assembled to a microscope.
FIG. 2 is a configuration diagram showing a digital camera for an optical device according to the first embodiment of the present invention.
FIG. 3 is a detailed explanatory view showing an enlarged main part of FIG. 2;
4 is a detailed explanatory view showing the control printed circuit board shown in FIG. 2 taken out. FIG.
FIG. 5 is a detailed explanatory view showing the displacement member in FIG. 2 taken out.
FIG. 6 is a configuration diagram showing a main part of a digital camera for an optical device according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 101a ... Mounting surface 101 ... Printed circuit board 102 ... Peltier element 103 ... Elastic member 104 ... Spacer 105 ... Displacement member 105a ... Displacement part 105b ... Fixing part 105c ... Hinge part 106 ... Lower exterior 106a, 106b ... Groove 107 ... Fixing member 108 ... female screw 109 ... inner lid 109a ... long hole 110 ... O-ring 111 ... cable 112 ... O-ring 113 ... stud 114 ... printed circuit board 115 ... glass member 116 ... desiccant 117 ... upper exterior 118 ... external connector 120a ... screw 120b ... Screw 201 ... Microscope body 202 ... Stage 203 ... Objective lens 204 ... Eyepiece lens 205 ... Lens barrel 206 ... Sample 207 ... Imaging lens 208 ... Camera body 209 ... CCD element 209a ... Imaging surface 209b ... Back surface 301 ... Stud 302 ... O-ring 303 ... Screw hole 304 Connector 400 ... through hole 500 ... piezoelectric elements 600 ... printed circuit board

Claims (9)

A solid-state image sensor for imaging an object;
A solid-state image sensor cooling means for cooling the solid-state image sensor;
A printed circuit board for electrical signal wiring;
The digital camera for an optical apparatus, wherein the printed circuit board for electrical signal wiring constitutes a part of a sealing means for sealing the solid-state image sensor and the solid-state image sensor cooling means . The digital camera for an optical apparatus according to claim 1, wherein the solid-state imaging element cooling means includes a Peltier element and a heat conductive member. 3. The digital camera for an optical apparatus according to claim 2, further comprising an elastic member having a good thermal conductor disposed between the Peltier element and the solid-state imaging element. In the digital camera for optical devices according to claim 1 or 2,
The printed circuit board has a connector for electrical connection, a through hole, and a mounting hole,
The connector is attached to a portion that functions as a lid of the sealing means,
The digital camera for an optical device, wherein the through hole and the attachment hole are attached to a place other than a portion functioning as a lid portion of the sealing means. In the digital camera for optical devices according to claim 4,
Comprises a inner lid of the wiring connector is connected to a printed circuit board connector having an opening therethrough,
The digital camera for an optical device, wherein the printed circuit board seals an opening of the inner lid. The digital camera for an optical device according to any one of claims 1, 2 and 3,
The sealing means further includes an exterior covering the solid-state image sensor cooling means,
The digital camera for an optical apparatus, wherein the printed circuit board functions as a lid for sealing the opening of the exterior. 7. The digital camera for an optical device according to claim 6, wherein heat generated by the solid-state imaging device is released to the outside through the elastic member, the Peltier device, a heat conductive member, and the exterior. Digital camera for optical devices. 8. The digital camera for an optical device according to claim 7, wherein the heat conductive member is a displacement member. The digital camera for an optical device according to claim 6,
The printed circuit board has a connector for electrical connection, a through hole, and a mounting hole,
The connector is attached to the opening of the exterior,
The digital camera for an optical device, wherein the through hole and the attachment hole are attached to a place other than the opening of the exterior.

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