JP2006014248A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera capable of preventing bad influence caused by steam broken into a sealed space. <P>SOLUTION: The camera comprises a CCD 11 to be housed in the sealed space 10, and a Peltier element 13 for cooling the CCD 11, wherein a water absorption component 12 for absorbing a waterdrop generated in an adjacent portion to be cooled by the Peltier element 13 of the CCD 11 is disposed in the sealed space 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a camera provided with an image sensor.

Conventionally, a CCD (Charge Coupled Device), a Peltier element that cools the CCD, first and second covers that form a sealed space that accommodates the CCD and the Peltier element, and a first cover and a second cover A camera provided with an O-ring as a sealing member disposed on the joint surface is known (see JP-A-6-45570).
JP-A-6-45570

  The performance of the CCD can be maintained by cooling the CCD. However, when the CCD is cooled when the outside air is hot and humid, there may be a problem such as condensation on the imaging surface of the CCD and blurring of the image.

  Therefore, the increase in the humidity in the sealed space is suppressed by improving the sealing rate of the sealed space or enclosing a gas such as nitrogen, thereby preventing condensation.

  However, for example, the O-ring deteriorates with aging. In addition, a repetition of expansion / contraction due to a temperature change may cause a gap between the O-ring and the cover, or a minute air hole may be formed in the O-ring itself. For this reason, it is difficult to completely prevent the outside air from entering the sealed space by a sealing member such as an O-ring.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a camera that can prevent the adverse effects of water vapor that has entered a sealed space.

  In order to solve the above-described problems, the invention described in claim 1 is a camera including an image sensor housed in a sealed space and a cooling unit that cools the image sensor, and is cooled by the cooling unit of the image sensor. It is characterized by having a water absorbing member that absorbs water droplets generated in the vicinity of the portion to be formed.

  According to a second aspect of the present invention, in the camera according to the first aspect, the water absorbing member is in contact with at least one of the imaging element and the cooling means.

  According to a third aspect of the present invention, in the camera according to the first or second aspect, the water absorbing member surrounds the imaging element.

  According to a fourth aspect of the present invention, in the camera according to any one of the first to third aspects, the water absorbing member is disposed in the sealed space.

  According to a fifth aspect of the present invention, in the camera according to the first aspect, the one end and the other end of the water absorbing member have a temperature difference, and the temperature of the one end close to at least one of the imaging element and the cooling means is the The temperature is lower than the temperature at the other end.

  According to a sixth aspect of the present invention, there is provided an imaging device that is accommodated in a sealed space formed by a housing and an optical filter fixed to the housing, and that faces the optical filter, and a cooling unit that cools the imaging device. The camera is provided with a water absorbing member that absorbs water droplets generated in the optical filter when the cooling operation of the cooling means is stopped.

  According to the camera of the present invention, it is possible to prevent an adverse effect due to water vapor entering the sealed space.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a first embodiment of the present invention.

  A sealed container that is the appearance of the camera is formed of a first casing 18 and a second casing 19.

  A sealed space 10 for accommodating a CCD (imaging device) 11 and a Peltier device (cooling means) 13 is formed in the sealed container by the first casing 18, the optical filter 16, the substrate 21, and the heat transfer member 14. Yes.

  The optical filter 16 is pressed against the lower portion of the first housing 18 by a member 20. An O-ring 17 </ b> A is disposed on the joint surface between the first housing 18 and the optical filter 16.

  The substrate 21 is used to supply power to the CCD 11 and the Peltier element 13 and to output an image signal obtained by the CCD 11 to the outside.

  The substrate 21 is sandwiched between the first housing 18 and the heat transfer member 14. The heat transfer member 14 is joined to the first housing 18 by screws 22.

  An O-ring 17 </ b> B is disposed on the joint surface between the substrate 21 and the first housing 18. An O-ring 17 </ b> C is disposed on the joint surface between the substrate 21 and the heat transfer member 14.

  The inside of the sealed space 10 formed as described above is once depressurized, and a gas such as nitrogen is sealed therein. However, outside air may enter the sealed space 10 due to the generation of voids due to aging of the O-rings 17A, 17B, and 17C.

  One end surface of the heat transfer member 14 is in pressure contact with one end surface of the Peltier element 13 via the heat transfer sheet 15A. The other end surface of the heat transfer member 14 is in pressure contact with the second housing 19 via the heat transfer sheet 15B.

  FIG. 2 is a partially enlarged view of FIG.

  The Peltier element 13 is mounted on the substrate 21.

  The CCD 11 is attached to the other end surface of the Peltier element 13 via a heat transfer sheet 15C. The supply current to the Peltier element 13 is controlled so that the CCD 11 becomes a predetermined temperature or less.

  A water absorbing member 12 is disposed so as to surround the CCD 11. The water absorbing member 12 contacts the CCD 11 and the Peltier element 13. The water absorbing member 12 is attached to the substrate 21 with a double-sided tape (not shown).

  As the water absorbing member 12, a special urethane sponge (for example, Soflas (trademark) / H type (Aion Co., Ltd.)), Japanese paper, nonwoven fabric, or the like is used.

  When a current is supplied to the Peltier element 13, the heat transfer member 14 is heated through the heat transfer sheet 15A by the Peltier effect. The heat of the heat transfer member 14 is radiated to the outside of the sealed container through the heat transfer sheet 15B and the second casing 19.

  Further, the heat generated in the CCD 11 is absorbed by the Peltier effect, and the CCD 11 is cooled. When the water vapor in the sealed space 10 becomes saturated, the water vapor condenses and water droplets are generated. This water droplet adheres to the vicinity of the part where the CCD 11 and the Peltier element 13 are in contact (the part where the temperature is the lowest inside the sealed space 10).

  As described above, the water absorbing member 12 surrounds and contacts the CCD 11 and the Peltier element 13, so that water droplets are absorbed by the water absorbing member 12.

  According to this embodiment, the O-ring deteriorates due to secular change, and even if outside air enters the sealed space 10 from the generated gap and water droplets adhere to the vicinity of the CCD 11, the water droplets are absorbed by the water absorbing member 12. Therefore, condensation can be prevented.

  Further, the water absorbing member 12 is disposed in the sealed space 10, and moisture is sealed in the sealed space 10 by a temperature difference between a portion (the other end) far from the Peltier element 13 and a portion (one end) near the Peltier element 13 of the water absorbing member 12. Circulates inside (the water absorbed by the water absorbing member 12 evaporates to become water vapor).

  At this time, a portion of the water absorbing member 12 far from the Peltier element 13 is relatively hotter than a portion near the Peltier element 13. This is because a temperature difference occurs in the water absorbing member 12 as the temperature in the vicinity of the Peltier element 13 becomes lower in the sealed space 10 than in places other than the vicinity.

  When the water vapor pressure in the sealed space 10 rises as the water absorption member 12 evaporates, and the water vapor pressure and the external air pressure are in an equilibrium state, outside air does not enter the sealed space 10 anew. No water droplets are generated in 10.

  FIG. 3 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a second embodiment of the present invention. The same reference numerals are given to the parts common to the first embodiment, and the description thereof is omitted. .

  The sealed container includes a housing 32 and a holder 30.

  A sealed space 40 for accommodating the CCD 11 and the Peltier element 13 is formed by the housing 32 and the optical filter 16 in the sealed container.

  The optical filter 16 is pressed against the lower part of the housing 32 by a holder 30. An O-ring 17 is disposed on the joint surface between the housing 32 and the optical filter 16.

  The substrate 31 is used to supply power to the CCD 11 and the Peltier element 13 and to output an image signal obtained by the CCD 11 to the outside. The substrate 31 is supported on the housing 32 via support members 33A and 33B.

  One end surface of the heat transfer member 34 is in pressure contact with one end surface of the Peltier element 13 via a heat transfer sheet 35A. The other end surface of the Peltier element 13 is in pressure contact with the housing 32 via a heat transfer sheet 35B.

  The CCD 11 mounted on the substrate 31 is attached to the other end surface of the heat transfer member 34.

  The water absorbing member 12 is disposed so as to surround the heat transfer member 34. The water absorbing member 12 contacts the CCD 11. In this embodiment, the Peltier element 13 and the heat transfer member 34 constitute a cooling means. The water absorbing member 12 is affixed to the substrate 31 with a double-sided tape (not shown).

  According to this embodiment, the same effects as those of the first embodiment can be obtained.

  In each of the above-described embodiments, the water absorbing member 12 is brought into contact with the CCD 11, but it is not always necessary to bring them into contact with each other, and the water absorbing member 12 is interposed via a gap capable of adsorbing water droplets to the CCD 11 and the Peltier element 13. May be arranged.

  FIG. 4 is a conceptual diagram showing an enlarged cross section of a Peltier element of a camera according to a third embodiment of the present invention.

  Since the structure of 3rd Embodiment and the structure of 1st Embodiment are the same except the Peltier device and the water absorption member 112, description about the same component is abbreviate | omitted.

  The Peltier element 113 is formed by sandwiching a circuit 113A made of a combination of two kinds of metals between a ceramic plate 113B and a ceramic plate 113B. The heat absorption side and the heating side of the Peltier element 113 are determined by the direction of the current flowing through the circuit 113A.

  A heat transfer member 14 is attached to the heating-side ceramic plate 113C via a heat transfer sheet 15A (see FIG. 1).

  Further, the CCD 11 is attached to the heat absorption side ceramic plate 113B via a heat transfer sheet 15C (see FIG. 1).

  The ceramic plate 113B on the heat absorption side is larger than the ceramic plate 113C on the heating side. A water absorbing member 112 for absorbing water droplets is disposed on the ceramic plate 113B so as to surround the circuit 113A.

  There is a gap between the water absorbing member 112 and the circuit 113A. The water absorbing member 112 is formed when the Peltier element 113 is manufactured.

  The water absorbing member 112 is formed by spraying and hardening a resin polymer having water absorption on the ceramic substrate 113B.

  According to this embodiment, the same effects as those of the first embodiment can be obtained, and the water absorption member 112 is formed on the ceramic substrate 113B when the Peltier element 113 is manufactured.

  In addition, since the water absorbing member 12 is manually attached to the substrate 21 during the assembly of the camera, the water absorbing member 12 needs to be larger than the size required for the sealed space 10 in order to smoothly perform the operation. . On the other hand, in this embodiment, since the water absorbing member 112 is formed integrally with the Peltier element 113 when it is manufactured, it is not necessary to attach the water absorbing member 112 to the substrate 21. As a result, the volume of the sealed space 10 can be reduced.

  The water absorbing member 112 may be brought into contact with the circuit 113A.

  Further, the material of the water absorbing member 112 may be the same as that of the first embodiment instead of the resin polymer. In this case, the water absorbing member 112 is fixed to the ceramic substrate 113B with an adhesive or a double-sided tape.

  FIG. 5 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a fourth embodiment of the present invention. The same reference numerals are given to the same parts as those in the first embodiment, and the description thereof is omitted. .

  The sealed container includes a housing 232 and a holder 230.

  A sealed space 240 for accommodating the CCD 11 and the Peltier element 13 is formed by the housing 232 and the optical filter 216 in the sealed container. An O-ring 217 is disposed on the joint surface between the housing 232 and the optical filter 216.

  The optical filter 216 and the CCD 11 are opposed to each other through a gap. The optical filter 216 is pressed against the lower portion of the housing 232 by the holder 230.

  Further, water absorbing members 212 and 213 are arranged on one surface of the optical filter 216 (surface on the sealed space 240 side).

  The water absorbing member 212 is formed in an annular shape so as not to block the optical path. The outer peripheral surface of the water absorbing member 212 is in contact with the inner peripheral surface of the housing 232. The water absorbing member 212 is attached to the optical filter 216 with a double-sided tape (not shown) or the like.

  The water absorbing member 213 is disposed inside the O-ring 217 so as to surround the sealed space 240. The water absorbing member 213 is compressed by the housing 232 and the optical filter 216. The water absorbing member 213 is in contact with the housing 232, the optical filter 216, and the O-ring 217.

  As the material of the water absorbing members 212 and 213, the same material as in the first embodiment can be used.

  The substrate 231 is used to supply power to the CCD 11 and the Peltier element 13 and to output an image signal obtained by the CCD 11 to the outside. The substrate 231 is supported by the housing 232 via support members 233A and 233B.

  One end surface of the heat transfer member 234 is in pressure contact with one end surface of the Peltier element 13 via the heat transfer sheet 235A. The other end surface of the Peltier element 13 is in pressure contact with the housing 232 via the heat transfer sheet 235B.

  The CCD 11 mounted on the substrate 231 is attached to the other end surface of the heat transfer member 234. In this embodiment, the Peltier element 13 and the heat transfer member 234 constitute a cooling means.

  When the supply of current to the Peltier element 13 is stopped, the temperature of the part cooled by the Peltier element 13 of the CCD 11 gradually increases, and the temperature of the optical filter 216 becomes the lowest in the sealed space 240. For this reason, water droplets adhere to one surface of the optical filter 216.

  As described above, since the water absorbing members 212 and 213 are positioned on one surface of the optical filter 216, water droplets on one surface of the optical filter 216 are absorbed by the water absorbing members 212 and 213. As a result, condensation is prevented.

  According to this embodiment, the same effect as that of the first embodiment is obtained, and even when a gap due to aging of the O-ring 217 or the like is generated, it is included in the outside air that enters the sealed space 240 through the gap. The absorbed water vapor is absorbed by the water absorbing member 213, so that the intrusion of the water vapor into the sealed space 240 is suppressed, and the water absorbing members 212 and 213 can be replaced simply by removing the holder 230 and the optical filter 216 from the housing 232. Workability is improved.

  In the above embodiment, the water absorbing member 213 is disposed inside the O-ring 217. However, as long as the water absorbing member 213 contacts the optical filter 216, the water absorbing member 213 may be positioned outside the O-ring 217.

  In the above embodiment, the water absorbing member 213 and the water absorbing member 212 are arranged on one surface of the optical filter 216. However, the present invention is not limited to this configuration, and either the water absorbing member 213 or the water absorbing member 212 is connected to the optical filter 216. You may arrange | position on one side of.

  Further, in each of the above embodiments, the CCD 11 is exemplified as an imaging unit, but the imaging element is not limited thereto. Moreover, although the Peltier device 13 was mentioned as an example as a cooling means, if it is an electronic cooling device which has the same function, an element will not be limited to this.

FIG. 1 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a first embodiment of the present invention. FIG. 2 is a partially enlarged view of FIG. FIG. 3 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a second embodiment of the present invention. FIG. 4 is a conceptual diagram showing an enlarged cross section of a Peltier element of a camera according to a third embodiment of the present invention. FIG. 5 is a conceptual diagram showing a cross-section of a sealed container that houses a CCD of a camera according to a fourth embodiment of the present invention.

Explanation of symbols

10, 40, 240 Sealed space 11 CCD (imaging device)
12, 112, 212, 213 Water absorbing member 13 Peltier element (cooling means)
34,234 Heat transfer member 216 Optical filter 232 Housing

Claims (6)

In a camera comprising an image sensor housed in a sealed space and a cooling means for cooling the image sensor,
A camera comprising a water absorbing member that absorbs water droplets generated in the vicinity of a portion cooled by the cooling means of the imaging device.   The camera according to claim 1, wherein the water absorbing member is in contact with at least one of the imaging element and the cooling means.   The camera according to claim 1, wherein the water absorbing member surrounds the imaging element.   The camera according to claim 1, wherein the water absorbing member is disposed in the sealed space.   The one end and the other end of the water absorbing member have a temperature difference, and the temperature of the one end close to at least one of the imaging element and the cooling unit is lower than the temperature of the other end. camera. In a camera that is housed in a sealed space formed by a housing and an optical filter that is fixed to the housing, and that includes an imaging device that faces the optical filter, and a cooling unit that cools the imaging device.
A camera comprising a water absorbing member that absorbs water droplets generated in the optical filter when the cooling operation of the cooling means is stopped.

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