JP2009060459A - Heating suppressing method of imaging device, cooling method of imaging device, and electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating suppressing method of an imaging device, cooling method of the imaging device and electronic camera in which the degree of freedom in disposing respective members is improved by reducing spatial volume occupied by a cooling member and power consumption due to the cooling member is suppressed. <P>SOLUTION: The present invention relates to a cooling method of an imaging device including: a temperature measuring step of measuring the temperature of a latent heat accumulating material disposed near an imaging device by means of a temperature sensor; a comparing step of comparing the measured temperature acquired in the temperature measuring step with a prescribed threshold; and a switching step of switching a period of an operating clock of the imaging device during a live view mode on the basis of a result of the comparison in the comparing step. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image sensor heat generation suppression method, an image sensor cooling method, and an electronic camera that efficiently cool the image sensor.

  In general, in an electronic camera such as an electronic camera, when an image pickup device that is an electronic component or a CPU (central processing unit) that constitutes a control circuit is installed, a countermeasure against heat is taken while providing dust resistance. It is requested.

  For example, in Patent Document 1, in a camera equipped with a variable focus lens device that changes the focal length by moving the photographing lens back and forth in the optical axis direction, dust or the like enters the casing by blowing outside air onto the surface of the lens barrel. A dustproof device that prevents this is disclosed.

  In the dustproof device disclosed in Patent Document 1, an air outlet is formed at the periphery of the hole portion through which the moving side barrel of the casing is inserted, and the air inlet and the air outlet formed at appropriate locations on the casing are connected to the air pipe. Communicate with each other. A suction fan and a filter are provided at the suction port to purify outside air and introduce it into the vent pipe. This suction fan is driven using the power of the lens barrel drive motor. Accordingly, the suction fan operates when the moving side lens barrel moves, and dust on the surface of the moving side lens barrel is blown away when dust easily enters.

  When the dustproofness is improved in this way, the temperature of the electronic component rises and the noise level rises. For example, in the case of an electronic camera device, the image quality is deteriorated. Such problems caused by the temperature rise of electronic components have become more serious with the recent enhancement of performance of image sensors and CPUs. Accordingly, the need for cooling methods and cooling structures in electronic cameras is increasing.

  By the way, as a cooling method and a cooling structure in such an electronic camera, for example, Patent Literature 2 and Patent Literature 3 disclose the following techniques.

  For example, Patent Document 2 discloses a technique of protecting a device in a television camera device by suppressing a temperature rise without stopping the operation of the camera device even when a cooling fan stops.

  That is, in the television camera device disclosed in Patent Document 2, a circuit that converts a video signal of an image sensor to a digital signal by an A / D converter, and then performs a digital process process to convert the signal to an analog signal by a D / A converter. In a camera apparatus having a cooling fan, the operation clock of the camera apparatus is switched from a basic clock signal to a clock signal divided by half of the basic clock signal in accordance with information that the cooling fan has stopped. .

  Patent Document 3 discloses a television camera device that aims to greatly reduce power consumption even at abnormally high temperatures.

That is, in the television device disclosed in Patent Document 3, the clock signal supplied to the A / D converter and the video process circuit is set to the same frequency as the horizontal transfer frequency of the image sensor during normal operation. In addition, when an abnormal rise in ambient temperature is detected in the temperature detection circuit, control is performed by the frequency division ratio in the frequency divider so that the frequency becomes 1/2 or less of the horizontal transfer frequency of the image sensor. The clock signal divided by the frequency divider is input to the lower bit processing circuit only during normal operation. If an abnormal increase in ambient temperature is detected in the temperature detection circuit, switch operation Stop.
JP-A-8-339017 JP 2002-271663 A Japanese Patent Laid-Open No. 10-271365

  However, according to the techniques disclosed in Patent Document 2 and Patent Document 3, no special consideration is given to the space volume occupied by the members required for cooling.

  Accordingly, the space between the electronic camera (such as an image sensor and AFE (Analog Front End) IC) that is a heating element and the temperature sensor is reduced due to the space volume in the electronic camera being narrowed by a member required for cooling. It can be considered that the distance becomes shorter than necessary. In such a case, of course, appropriate temperature management becomes difficult.

  Furthermore, for example, in an electronic camera, the amount of heat generated by the heating element in various modes such as the continuous shooting mode differs in each mode. Therefore, cooling should be performed by performing temperature management corresponding to each of these modes. For example, when driving a fan for cooling, control should be performed in consideration of power consumption by the fan.

  The present invention has been made in view of the above circumstances, and by performing temperature management based on a predetermined temperature of the latent heat storage material, an instantaneous temperature increase around the image sensor can be suppressed, and live performance can be suppressed. An object of the present invention is to provide a method for suppressing heat generation of an image sensor, a method for cooling the image sensor, and an electronic camera, in which heat generation from the image sensor due to clock switching in view mode is suppressed.

  In order to achieve the above object, the image sensor heat generation suppression method according to the first aspect of the present invention measures the temperature of a predetermined latent heat storage material disposed in the vicinity of the image sensor using a temperature sensor. An operation clock for the live view mode based on the temperature measurement step, the comparison step for comparing the measured temperature acquired in the temperature measurement step with the phase change temperature of the latent heat storage material and a predetermined threshold, and the comparison result in the comparison step And a switching step for switching the period.

  In order to achieve the above object, a cooling method for an image sensor according to a second aspect of the present invention includes a temperature measurement step in which a temperature sensor measures a phase change temperature of a latent heat storage material arranged in the vicinity of the image sensor, and The comparison step of comparing the measured temperature acquired in the temperature measurement step with a predetermined threshold value, and the predetermined threshold values are a first threshold value T1, a second threshold value T2, and a third threshold value T3, and the temperature measurement step If the measured temperature acquired in step t is t, when it is determined in the comparison step that the measured temperature t satisfies T1 <t ≦ T2, the operation clock cycle of the image sensor is not switched in the switching step. , T ≦ T1 is satisfied, the operation clock cycle of the image sensor is set to the basic clock cycle in the switching step. When it is determined that the measured temperature t satisfies T2 <t, in the switching step, the period of the operation clock of the image sensor is set to twice the period of the basic clock, and T3 <t is set to the measured temperature t. Is determined to satisfy the above condition, the period of the operation clock of the image sensor is set to twice the period of the basic clock and the forced air cooling device is driven in the switching step.

  In order to achieve the above object, an electronic camera according to a third aspect of the present invention includes an imaging device, a latent heat storage material and a temperature sensor arranged in the vicinity of the imaging device, and a temperature measured by the temperature sensor. Comparing means for comparing with the phase change temperature of the latent heat storage material, and control means for switching the cycle of the operation clock in the live view mode based on the comparison result by the comparing means.

  In order to achieve the above object, an electronic camera according to a fourth aspect of the present invention includes a latent heat storage material disposed in the vicinity of an imaging device, a temperature sensor that measures a phase change temperature of the latent heat storage material, and the temperature Comparison means for comparing the temperature measured by the measurement sensor with a predetermined threshold, and the predetermined threshold are a first threshold T1, a second threshold T2, and a third threshold T3, and the measurement measured in the temperature measurement step When the temperature is t, when the comparison unit determines that the measured temperature t satisfies T1 <t ≦ T2, the control unit does not switch the cycle of the operation clock of the image sensor, and t If the comparison means determines that ≦ T1 is satisfied, the control means sets the period of the operation clock of the image sensor to the period of the basic clock, and determines that T2 <t is satisfied by the comparison means. In this case, the control means sets the period of the operation clock of the image sensor to a period twice that of the basic clock, and if the comparison means determines that T3 <t is satisfied, the control means The means is characterized in that, in the switching step, the period of the operation clock of the image sensor is set to a period twice the period of the basic clock and the forced air cooling device is driven.

  According to the present invention, an instantaneous temperature rise around the image sensor can be suppressed by performing temperature management based on a predetermined temperature of the latent heat storage material, and from the image sensor by clock switching in the live view mode. It is possible to provide a method for suppressing heat generation of an image sensor that suppresses heat generation, an image sensor cooling method using a forced air cooling device, and an electronic camera.

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

[First embodiment]
FIG. 1A is a longitudinal sectional view showing the main configuration of the electronic camera according to the first embodiment of the present invention. In the following description, the subject side in the optical axis O direction of the photographing lens shown in FIG. 1A is defined as the front, and the imaging surface side (imaging surface side) is defined as the rear. The Y direction perpendicular to the optical axis O is the vertical direction, and the + side is the upward direction.

  The electronic camera according to the first embodiment includes a camera body 1A and an interchangeable lens barrel 1B having an optical member (imaging lens 3) that can be attached to and detached from the camera body 1A.

  An imaging device is accommodated in the camera exterior 2 of the camera body 1A, and the imaging device is fixedly supported by the camera exterior 2, and has a main body structure 4 having a central opening 4a along the optical axis O; A body side mount 14 as a photographing lens support member to which the interchangeable lens barrel is attached and detached, and a main mirror 5 as a constituent member disposed along the optical axis O in the central opening 4 a of the main body structure 4. A focal plane shutter (hereinafter simply referred to as a shutter) 6, an imaging module 8 having a cooling structure, a fixed screen supported on the upper side of the main body structure 4, and a focusing screen 9 as a member constituting the finder device, a penta A prism 10, an eyepiece lens 11, a monitor display window 13, and a liquid crystal monitor device (hereinafter referred to as an LCD) disposed inside the monitor display window 13 Referred) includes a 12, a.

  An LCD 12 is arranged inside the monitor display window 13 on the back side of the camera exterior 2.

  The main body structure 4 is a frame that supports the imaging module 8, and is connected to the imaging element support plate 122. The main body structure 4 is a member that can be reduced in weight and reduced in cost. For example, a polycarbonate resin or a PPS (polyphenylene sulfide) resin in which a filler such as carbon fiber is mixed as a material having high thermal conductivity is used. Become.

  The main mirror 5 rotates between a down position (position shown in FIG. 1A) for reflecting the subject luminous flux toward the upper focusing screen 9 and an up position retracted from the subject optical path of the optical axis O shown in FIG. It is provided as possible.

  The shutter 6 is provided on the optical axis O and disposed at a rear position of the main mirror 5 at the down position.

  The body side mount 14 is fixed and provided in a state of being applied to the front surface of the main body structure 4.

  The heat generated in the vicinity of the image sensor 121 is partly stored by the latent heat storage material sheet 122 a included in the image sensor support plate 122 connected to the main body structure 4. As a result, it is possible to eliminate the need for a separate space for disposing a heat sink for dissipating heat generated in the vicinity of the image sensor 121.

  Here, the main body structure 4 is provided with the latent heat storage material 104a, which is made of a phase change material and close to the imaging element support plate 122, and is thermally coupled by, for example, insert molding. Yes.

  The latent heat storage material 104a is filled with an organic heat storage material such as paraffin, carbon fiber made of a material that easily conducts heat, or a paraffin filled with a gel that can be held in a solid form even at a melting temperature or higher, or a polymer. It is composed of so-called heat storage microcapsules covered with a core material such as paraffin or inorganic hydrated salt, and is formed so that it can be melted and solidified by changing its phase at a temperature below the use limit temperature of the image sensor 121, for example, 60 to 70 ° C. ing. Thereby, the latent heat storage material 104a holds the main body structure 4 at a constant temperature of 60 to 80 ° C. which is lower than the use limit temperature of the image sensor 121, and thermally controls the image sensor 121 to a desired value.

  The organic heat storage material constituting the latent heat storage material 104a is formed, for example, of paraffin filled with paraffin or carbon fiber having high thermal conductivity. Moreover, it is also possible to use a core material or a synthetic material mixed with a synthetic resin as a heat storage microcapsule containing paraffin or inorganic hydrate salt coated with a polymer. Moreover, although melting | fusing point of the latent heat storage material 104a was 60 degreeC or more, as a substance which melt | dissolves at 45 degreeC-59 degreeC, it is also possible to replace with inorganic type (for example, sodium acetate pentahydrate). In this way, by using an adhesive molding method in which the latent heat storage material 104a is joined to the PPS resin by an insert molding method or a metal material, the area of the heat radiating plate material can be reduced and the plate thickness can be reduced, thereby reducing the size. It becomes possible.

  That is, the latent heat storage material 104a is formed so as to be capable of melting / solidifying by changing phase at a temperature lower than the use limit temperature of the image sensor 121, for example, about 60 ° C. to 70 ° C. Thereby, the latent heat storage material 104a keeps the main body structure 4 at a constant temperature of 60 ° C. to 70 ° C. which is lower than the use limit temperature of the image sensor 121, and thermally controls the image sensor 121 to a desired value. Contribute to.

  And it becomes possible to enclose the said image pick-up element 121 which is one of the heat sources with the said latent heat storage material 104a and the said latent heat storage material sheet | seat 122a from three directions.

  By the way, in a normal photographing state, the heat generated from the image sensor 121 rises from below the electronic camera, and the temperature near the reinforcing rib 4b provided near the pentaprism 10 of the main body structure 4 rises.

  However, according to the cooling method and the electronic camera of the image sensor according to the first embodiment, the heat generated in the image sensor 121 is stored by the latent heat storage material 104a. A significant increase can be prevented, and the temperature inside the electronic camera can be suppressed from becoming an abnormally high temperature.

  The effect may be further enhanced by joining a member in which the latent heat storage material 104a is formed in a sheet shape to the joint surface between the main body structure 4 and the image sensor support plate 122.

  By the way, the main body structure 4 is provided with concave and convex reinforcing ribs 4b on the wall surface in a direction perpendicular to the paper surface. Therefore, even when the latent heat storage material 104a is liquefied, the strength of the main body structure 4 is ensured by the reinforcing rib 4b.

  Hereinafter, the imaging module 8 will be described in detail with reference to FIG.

  The imaging module 8 is arranged at a rear position of the shutter 6 and is directly supported in close contact with the main body structure 4, and an imaging element support plate 122 constituting a holding member, and a front side of the imaging element 121 An image sensor 121 whose non-imaging surface (back surface) side is bonded and fixed to the image sensor support plate 122 via an extremely thin insulating sheet 128, and a non-imaging surface side of the image sensor 121. A connection flexible printed circuit board (hereinafter referred to as a connection FPC) 135 that is attached and connected and connected to the printed circuit board 140 of the imaging circuit via a connector 139 and the non-imaging surface behind the image sensor 121 is imaged. An image sensor cooling unit 130 supported by the element support plate 122, and a printed circuit board 140 for an image sensor disposed behind the latent heat storage material sheet 122a. Consisting of.

  Here, the dust-proof mechanism 119 includes a base 123 fixed to the main body structure 4, a dust-proof glass 124 supported by the base 123 via a support member 127 made of an elastic body, a rubber frame (non- And a piezoelectric element 126 mounted on the tip of the dust-proof glass 124 via an optical filter 125 supported by a pressing plate on the back surface side of the base 123. The dust-proof mechanism 119 prevents dust from entering the imaging surface side surface of the imaging element 121 surrounded by the dust-proof glass 124 and the base 123.

  Further, the dust-proof glass 124 is driven to vibrate by the piezoelectric element 126, whereby dust adhering to the dust-proof glass 124 is removed.

  The printed circuit board 140 includes a connector 139 connected to the connection FPC 135, a control circuit unit (CPU) 141, an AFE (analog front end) IC element 42 as an image processing circuit component, and the latent heat storage material sheet 122a. And a drive circuit (not shown in FIG. 1A) for driving a fan or pump that is a forced air cooling device (not shown).

  The imaging element support plate 122 is formed of an aluminum plate or a stainless steel plate, and holds the imaging element 121 and also has a heat dissipation function of the imaging element. In addition, the imaging element support plate 122 is fixedly attached to the back surface of the main body structure 4, and the latent heat storage material sheet 122 a is provided on a surface opposite to the surface facing the imaging element 121. Is provided.

  In addition, as a material of the image pick-up element support plate 122, for example, a material having a high thermal conductivity which is the same material as that of the main body structure 4 and a polycarbonate or PPS resin mixed with a filler such as carbon fiber is used. May be. As this PPS resin, for example, a molded product of polyphenylene sulfide resin filled with spherical graphite and amorphous (glass) fibers or carbon fibers is used.

  The insulating sheet 128 is a sheet having a predetermined thickness and a very thin thickness, and is provided with an adhesive application hole (not shown). Specifically, as the insulating sheet 128, for example, an insulating sheet coated with an infrared cut filter (not shown), an infrared cut filter (not shown), or a white paint sheet (emissivity 0.1 to 0.6 or less). An insulating sheet joined with is used.

  The image pickup device 121 is a bare chip type (non-package) image pickup device, and a bump for connection to the connection FPC 135 is provided on the surface of the image pickup surface (photoelectric conversion surface). The imaging surface side surface is located at a predetermined distance from the non-imaging surface side surface that is the surface opposite to the imaging surface side.

  Here, the main body structure 4 is connected to the image sensor support plate 122. A part of the heat generated around the image sensor 121 is stored by the latent heat storage material sheet 122a included in the image sensor support plate 122.

  Hereinafter, an external configuration of the electronic camera according to the first embodiment of the present invention will be described with reference to FIG. 1B.

  As shown in the figure, the electronic camera according to the first embodiment includes a camera body 1A and an interchangeable lens barrel (FIG. 1A) mounted by being interchangeably mounted at the front center of the camera body 1A. (Not shown in FIG. 1B).

  Here, the camera body 1A constituting the external shape of the electronic camera is formed in a slightly horizontally long shape as a whole, and includes a photographing lens at a substantially central position on the front side on the optical axis of the photographing lens. A ring-shaped body-side mount portion 3 for loading the interchangeable lens barrel interchangeably is provided.

  A lens attaching / detaching button 51 is provided in the vicinity of the mount portion 3. In addition, the camera body 1 is formed in a grip shape that appropriately protrudes at an end portion that is deviated to the left from a vertical plane including the optical axis when viewed from the front side so as to be held by the right hand of the operator during shooting. A grip portion 52 serving as a holding region.

  On the top of the grip portion 52, a shutter button 53 and an exposure correction button 54 that are operated with a fingertip while holding the grip portion 52 are provided. Further, the camera body 1A includes a mode dial 55 and a control dial 56 including a power switch at the upper left side when viewed from the front side, and setting switching of various modes and the like is possible.

  The camera body 1A includes an AF (Auto Focus) frame selection button, a one-touch white balance button, an adjustment button such as white balance and AF, and an OK button on the back side of the grip portion 52.

  Further, the camera body 1A includes a monitor display window 13 (see FIG. 1A) at a position on the optical axis adjacent to the grip portion 52 on the back side. This monitor display window 13 is a TFT (Thin Film Transistor) type monitor that displays various settings and adjustment items in addition to the photographed image, and is a large rectangular display panel that occupies about half of the rear side area. is there.

  The camera body 1A includes a play button, an erase button, a menu button, an information display button, and the like on the left side of the monitor display window 13 when viewed from the back side. Furthermore, the camera body 1A includes an optical finder 57 that the operator looks into at the time of shooting and a hot shoe 58 to which an external flash is attached at the top of the monitor display window 13 when the camera is turned upside down.

  Further, in the camera body 1A, a sponge-like filter member having air permeability with respect to the intake holes 81, 87 and the exhaust holes 82 is provided in close contact with the inner surface of the exterior cover.

  By providing these filter members, dust or the like can enter the camera body 1A from the intake holes 81 and 87 and the exhaust hole 82 when an air flow flows by driving the cooling fan 71 that is an air cooling fan or when the air cooling fan is stopped. Intrusion is prevented.

  Further, as the cooling fan 71 is driven, the air is sucked from the suction holes 81 and 87 formed on the outer surface of the camera body 1A by being arranged at the upper and lower positions of the monitor display window 13, and passes through the flow path around the printed circuit board 140. As a result, an air flow exhausted from the exhaust hole 82 to the side of the camera body 1 is also generated, so that the forced cooling of the printed circuit board 140 can be performed efficiently over the entire surface.

  Hereinafter, the electric control unit of the electronic camera according to the first embodiment will be described with reference to FIG.

  As shown in FIG. 2, the electric control unit of the camera body 1 </ b> A and the interchangeable lens barrel 1 </ b> B is connected to the CPU 141, which is a control unit that controls each part of the camera body 1 </ b> A and the interchangeable lens barrel 1 </ b> B. And various control elements that are controlled by the CPU 141 or that output detection signals to the CPU 141. The CPU 141 is connected to the temperature sensor 143 and includes a ROM 246 in which melting temperature data of various latent heat storage materials and a temperature offset amount due to a positional shift between the temperature sensor and the latent heat storage material are stored.

  Specifically, the control element drives a shutter charge drive circuit 232 for driving the shutter drive motor 209, a shutter drive circuit 234 for driving the shutter control magnet 211, and a main mirror drive motor 210. Main mirror drive circuit 233, fan drive circuit 230 for driving fan drive motor 201, which is a motor attached to cooling fan 71 (see FIG. 1B), which is one of forced air cooling devices, and image sensor shift. An image sensor shift driving circuit 231 for driving the drive motor 203, a focusing drive circuit 237 for driving the focusing drive motor 224, and a distance measuring sensor (ranging element) 216 are driven, and an output of the sensor is captured. A distance measuring circuit 236 that performs distance measurement for phase difference AF, and the image sensor 1 1 and captures an image signal from the image sensor 121 and performs image processing, an image recording unit 239 for recording the captured image signal in the memory unit, and the LCD 12 to display a live view image. An LCD driving circuit 241 for image capturing, a photographing mode changeover switch 242 which is a switching means for instructing switching between the optical finder mode and the live view mode, and a photographing signal generating means which is a first for performing focusing. A first release switch 243 for outputting a shooting signal, a 2nd release switch 244 for outputting a second shooting signal for performing imaging (exposure) following the first shooting signal, an image processing circuit 238, A bus line 245 composed of input / output signal lines such as an image recording unit 239 and an LCD drive circuit 241; Obtain.

  Instead of the fan drive circuit 230 for driving the fan drive motor 201, a pump drive circuit for driving a pump to be described later may be provided, or of course both of them may be provided.

  By the way, the main mirror 5 is rotatably supported by a mirror support shaft (not shown) in the mirror box of the camera body 1A, and a sub mirror (not shown) is rotatably supported on the back surface portion. Yes. When the main mirror 5 is driven to be charged by the main mirror drive motor 210, the main mirror 5 is rotated to a down position located in an oblique state on the optical path of the imaging light of the imaging optical axis O of the interchangeable lens barrel 1B. When the charging state is released, the state is rotated to the up position retracted from the optical path of the photographing light. In conjunction with the rotational movement, the sub mirror (not shown) is positioned obliquely on the optical axis O on the back surface of the main mirror 5 in the down state (the main mirror 5 is in the down position). In the up state (the state in which the main mirror 5 is in the up position), the main mirror 5 is folded and positioned.

  When the main mirror 5 is in the down position, the photographing light flux along the optical axis O is reflected by the main mirror 5 toward the upper focusing screen 9 along the optical axis O, and passes through the pentaprism 10 and the eyepiece 11. Thus, the subject image is observed at the eye (not shown) of the photographer. At the same time, a part of the photographing light beam that has passed through the half mirror part (semi-transmissive part), which is the transmission surface at the center of the main mirror, is reflected obliquely downward along the distance measuring optical axis O by the sub mirror (not shown). Then, it enters a distance measuring lens (not shown) as a distance measuring light beam, forms an image on a light receiving surface of a distance measuring sensor (not shown), and outputs a distance measuring signal for phase difference AF.

  When the main mirror 5 is in the up position, the photographing light flux along the optical axis O reaches the shutter 6. When the shutter is in the open state, the photographic light beam is imaged on the imaging surface of the image sensor 121, and exposure (imaging) is performed.

  The shutter 6 opens and closes the shutter opening by the movement of the front curtain and the rear curtain, but the shutter drive motor 209 is charged to the non-exposure shutter closed state (the front curtain is in the closed position and the rear curtain is in the open position). To go to). In the shutter closed state, when the front curtain side magnet among the shutter control magnets 211 is driven to release, the shutter opening is opened and the exposure state is set. After the shutter time elapses, the shutter opening is closed when the rear curtain magnet is driven to release.

  On the LCD 12, the subject imaging signal captured by the imaging device 121 in the live view mode is processed by the image processing circuit 238 and displayed as a live image by the LCD driving circuit 241 under the control of the live view means of the CPU 141. In addition, a captured subject image is displayed in the optical viewfinder mode and the live view mode.

  The image sensor shift drive motor 203 is a motor of a drive mechanism provided in the vicinity of the image sensor 121 to perform so-called shift drive for image blur correction. The image pickup device shift drive circuit 231 performs shift drive by causing a current to flow through the drive mechanism based on the shake of the optical axis and the like, thereby suppressing the shake of the image formed on the image pickup device 121.

  The fan drive motor 201 is a motor attached to a cooling fan 71 (see FIG. 1B) which is one of forced air cooling devices for cooling the image sensor 121 and the like. The fan drive motor 201 is driven by the fan drive circuit 230 under the control of the CPU 141.

  Hereinafter, operation control by the CPU 141 in the electronic camera according to the first embodiment will be described with reference to a flowchart shown in FIG. Here, in order to focus on the operation control unique to the electronic camera according to the first embodiment, for the sake of convenience of explanation, description of the operation control similar to that of the conventional electronic camera is basically omitted.

  First, when the power of the electronic camera is turned on, the electronic camera system is initialized (step S100). The setting mode at this time is an optical finder mode.

  Subsequently, it is determined whether or not a shooting mode switching operation has been performed by the user (a mode switching switch (not shown) has been operated) (step S110). When step S110 is branched to NO, the process branches to step S120 described later.

  On the other hand, when step S110 is branched to YES, it is determined whether or not the operation performed by the user in step S110 is a switching operation to the live view mode (step S111).

  When step S111 is branched to NO, the optical finder mode is set (step S112). Then, the main mirror 5 is driven to the down position (step S113). If a live view operation has been performed, the live view operation is also stopped in step S113. When the process in step S113 is completed, the process proceeds to step S120 described later.

  When step S111 is branched to YES, the live view mode is set (step S114). Subsequently, it is determined whether or not the temperature t measured by the temperature sensor 143 satisfies the following equation (step S115).

t> T2 (Formula 1)
Here, T2 is a threshold for switching the frame rate in the live view display in the live view mode (details will be described later).

  When step S115 is branched to YES, the live view display frame rate is set to 15 ftp (step S117), and the process proceeds to step S118 described later. On the other hand, when step S115 is branched to NO, the frame rate for live view display is set to 30 ftp (step S116), and the process proceeds to step S118 described later.

  In other words, in the electronic camera according to the first embodiment, when the temperature t measured by the temperature sensor 143 satisfies the condition shown in (Formula 1), the subject in the live view mode is used to suppress heat generation. The cycle of the operation clock signal of the image sensor 121 that captures the imaging signal is switched to a cycle that is ½ of the cycle of the basic clock signal.

  On the other hand, if the temperature t measured by the temperature sensor 143 does not satisfy the condition shown in (Expression 1), there is no need to suppress heat generation, so the period of the operation clock signal of the image sensor 121 is as follows. The period of the basic clock signal is maintained.

  Of course, if the cycle of the operation clock signal of the image sensor 121 is switched to a short cycle, the frame rate in the live view display is increased. Conversely, if the cycle of the operation clock signal of the image sensor 121 is switched to a long cycle, The frame rate in live view display is low.

  In step S118, the main mirror 5 is driven to the up position, and a normal live view operation is started.

  After the processing in step S118 or step S113 is completed, or when step S110 is branched to NO, the temperature t measured by the temperature sensor 143 is compared with the following predetermined threshold including T2. Based on the comparison result, the process proceeds to the next four operation controls (step S120). Specifically, the following processing is performed in step S120.

  That is, the predetermined threshold values are T1, T2, and T3, and it is determined which of the following conditional expressions the temperature t satisfies. It is assumed that T1 <T2 <T3.

T1 <t ≦ 2 (Formula 2)
t ≦ T1 (Formula 3)
T2 <t (Formula 4)
T3 <t (Formula 5)
If it is determined in step S120 that the temperature t satisfies the (formula 2), the process proceeds to step S130 described later.

  In step S120, when it is determined that the temperature t satisfies the (formula 3), it is determined whether the live view mode is set and the frame rate of the live view display is 15 ftp ( Step S125). When step S125 is branched to YES, the frame rate of the live view display is set to 30 ftp (step S126). When step S125 is branched to NO or after the processing in step S126 is completed, it is determined whether or not the fan is in a driving state (step S127). When step S127 is branched to NO, the process proceeds to step S130 described later. On the other hand, when this step S127 is branched to YES, the driving of the fan is stopped (step S128), and the process proceeds to step S130 described later.

  If it is determined in step S120 that the temperature t satisfies the (formula 4), it is determined whether the viewfinder mode is set to the live view mode and the frame rate of the live view display is 30 ftp. Judgment is made (step S123). When step S123 is branched to YES, the frame rate of the live view display is set to 15 ftp (step S124). When step S123 is branched to NO or after the processing in step S124 is completed, the process proceeds to step S130 described later.

  If it is determined in step S120 that the temperature t satisfies the (formula 5), it is determined whether or not the fan is being driven (step S121). When step S121 is branched to NO, the fan is started to be driven (step S122). When step S121 is branched to YES or after the process in step S122 is completed, the process proceeds to step S130 described later.

  In step S130, it is determined whether or not a release switch (not shown) has been pressed by the user (step S130). When step S130 is branched to NO, the process proceeds to step S133 described later.

  On the other hand, when step S130 is branched to YES, a normal photographing preparation operation (AE, AF, etc.) is performed (step S131), and then a normal photographing operation is performed (step S132). Note that the shooting preparation operation performed in step S131 and the shooting operation performed in step S132 are the same as those performed in a normal electronic camera, and thus detailed description thereof is omitted here.

  After the processing in step S132 is completed or when step S130 is branched to NO, it is determined whether or not a power switch (not shown) of the electronic camera is turned off (step S133). When step S133 is branched to NO, the process returns to step S110 described above. On the other hand, when the step S133 is branched to YES, the system of the electronic camera is stopped (step S134).

  As described above, in the electronic camera according to the first embodiment, the period of the operation clock signal of the image sensor 121 is appropriately switched based on the temperature t measured by the temperature sensor 143, so that it can be used in the live view mode. Change the frame rate for live view display appropriately. Thereby, excessive heat generation of the image sensor 121 can be suppressed.

  The frame rate switching timing will be described below with reference to FIG. 4, which is a graph showing how the frame rate is switched in the live view display described above. In the graph, the vertical axis represents temperature and the horizontal axis represents time.

  As shown in the figure, when the temperature t is equal to or lower than the T1 and the electronic camera is set to the live view mode, the temperature inside the electronic camera is subjected to a special cooling measure. Assuming that the temperature is not necessary, the frame rate for live view display is set to 30 ftp and the driving of the fan is also stopped.

  Further, when the temperature t is higher than the T2 and the electronic camera is set to the live view mode, the temperature inside the electronic camera needs to be subjected to a special cooling measure. Heat generation is suppressed by setting the frame rate of the live view display to 15 ftp assuming that the temperature is a certain temperature.

  Further, when the temperature t becomes a value higher than the T3, the driving of the fan is started assuming that the temperature inside the electronic camera is a temperature at which the cooling by the fan needs to be performed.

  On the other hand, when the temperature t is a value larger than the T1 and not more than the T2, the frame rate switching and the fan driving start / stop described above are not performed. In this way, when the temperature t is equal to or lower than a predetermined temperature, a dead zone region in which no cooling control is performed is provided to prevent the operation control of the electronic camera from becoming complicated.

  As described above, according to the first embodiment, the method for suppressing heat generation of the imaging element that reduces the space volume occupied by the cooling member, increases the degree of freedom of arrangement of each member, and suppresses power consumption by the cooling member. An imaging device cooling method and an electronic camera can be provided.

  The frame rates of 15 ftp and 30 ftp described above are examples, and the frame rate value is not limited to these values. That is, 15 ftp may be read as “low frame rate”, and 30 ftp may be read as “high frame rate”, and a desired value may be set for each. In addition, when the temperature is equal to or higher than T2, it is possible to stop the operation cycle at a low frame rate. At this time, the temperature is detected at regular intervals from a temperature sensor 143 arranged opposite to the latent heat storage material sheet 122a, and for example, a cooling fan drive time and a stop time are selectively driven by a timer (not shown). You can also By doing in this way, the power consumption of a battery can be suppressed. Further, the CPU 141 monitors the remaining battery level. If the remaining battery level is equal to or lower than a predetermined value, the CPU 141 warns the user that the remaining battery level is low and then forcibly turns off the main power switch.

[Second Embodiment]
Hereinafter, an image sensor heat generation suppression method, an image sensor cooling method, and an electronic camera according to a second embodiment of the present invention will be described.

  For the sake of convenience of explanation, explanations common to the image sensor heat generation suppression method, image sensor cooling method, and electronic camera according to the first embodiment will be omitted, and differences will be described.

  FIG. 5 is a cross-sectional view showing a configuration of the imaging module 8 in the electronic camera according to the second embodiment.

  A so-called bare chip type imaging device 121 has a back-side insulating sheet 128 having a predetermined shape attached to the back side thereof by adhesion or the like.

  Note that a heat reflecting member, which is an infrared reflecting member (not shown), for example, is preferably bonded onto the back side insulating sheet 128 of the imaging element. The heat reflecting member is made of, for example, an aluminum material and is mirror-finished, and a coating such as a metal foil, a metal oxide, an infrared cut filter, or a sheet of white paint is bonded to the surface of the heat reflecting member so that the emissivity is 0. A surface treatment of 1 to 0.6 or less is performed. Since this heat reflecting member radiates heat from the image sensor 121 as infrared rays and reflects infrared rays from the outside, it is possible to suppress an increase in re-temperature of the image sensor 121 due to radiant heat.

  The imaging element 121 has a rear insulating sheet 128 facing the FPC board 300 facing a heat radiation opening 311 provided in a flexible printed wiring board (hereinafter referred to as an FPC board) 300 that can be elastically deformed, for example. It is mounted and electrically connected to the FPC board 300 via the lead terminal 302.

  In this image sensor 121, an optical low-pass filter 313 assembled in a rubber frame 312 is coaxially disposed on the light receiving surface. The rubber frame 312 of the optical low-pass filter 313 is made of a heat conductive material such as a molding material filled with granular graphite and carbon or glass fiber, which is a lens frame constituting the device casing, and filled with carbon or glass fiber. It is supported by a holding portion 315 provided in a frame member 314 made of an excellent material. The shutter 6 is assembled at the front end of the frame member 314 so as to face the optical low-pass filter 313.

  A transparent glass substrate 317 constituting a dust-proof mechanism is placed on the holding portion 315 of the frame member 314 between the optical low-pass filter 313 and the shutter 6 on the optical low-pass filter 313, for example, with a piezoelectric element. With the vibration member 318 interposed, the upper surface side of the vibration member 318 is pressed by the pressing member 319 so as to be freely vibrated, and is arranged in an airtight manner. The transparent glass substrate 317 vibrates in an airtight state against the elastic force of the pressing member 319 when the vibration member 318 is driven and vibrated via a drive control unit (not shown). Dust and the like adhering to the upper surface and the like are removed to prevent entry into the optical low-pass filter 313.

  In addition, on the back side of the image sensor 121, an element support member 320 constituting a heat radiating member formed of a material having excellent thermal conductivity such as aluminum, stainless steel, or a PPS resin molding material is disposed. For the element support member 320, when aluminum or stainless steel is used for the back side of the FPC board 300, the FPC board 300 is used when using the technique such as the adhesive 333 having high thermal conductivity, or the PPS resin. They are joined and assembled by a direct support insert molding (without using the adhesive 333).

  Here, the frame member 314 is a synthetic resin material having excellent thermal conductivity mixed with a filler such as metal oxide or ceramic, for example, PPS (polyphenylene sulfide) resin in which spherical graphite is filled with glass fiber, carbon resin or the like. It is formed. In the frame member 314, a latent heat storage material 104a that changes in phase and is made of a phase change material in the vicinity of the element support member 320 is thermally coupled by, for example, insert molding. The latent heat storage material 104a is filled with an organic heat storage material such as paraffin, carbon fiber made of a material that easily conducts heat, or a paraffin filled with a gel that can be held in a solid form even at a melting temperature or higher, or a polymer. It is composed of so-called heat storage microcapsules covered with a core material such as paraffin or inorganic hydrated salt, and is formed so that it can be melted and solidified by changing its phase at a temperature below the use limit temperature of the image sensor 121, for example, 60 to 80 ° C. ing. As a result, the latent heat storage material 104a keeps the frame member 314 at a constant temperature of 60 to 80 ° C., which is equal to or lower than the use limit temperature of the image sensor 121, and thermally controls the image sensor 121 to a desired value.

  The organic heat storage material constituting the latent heat storage material 104a is formed of paraffin filled with, for example, paraffin or carbon fiber having high thermal conductivity. Moreover, it is also possible to use a core material or a synthetic material mixed with a synthetic resin as a heat storage microcapsule containing paraffin or inorganic hydrate salt coated with a polymer. Moreover, although melting | fusing point of the latent heat storage material 104a was 60 degreeC or more, as a substance which melt | dissolves at 45 degreeC-59 degreeC, it is also possible to replace with inorganic type (for example, sodium acetate pentahydrate). In this way, by using an adhesive molding method in which the latent heat storage material 104a is joined to the PPS resin by an insert molding method or a metal material, the area of the heat radiating plate material can be reduced and the plate thickness can be reduced, thereby reducing the size. It becomes possible.

  The frame member 314 is provided with reinforcing ribs 341 that are concave and convex in the direction perpendicular to the paper surface on the wall surface, and the strength in a state where the latent heat storage material 104a is liquefied is secured by the reinforcing ribs 341.

  The element support member 320 is provided with an opening 301 corresponding to the back-side insulating sheet 128 of the imaging element 121, and heat transfer is performed using the phase change of the working fluid so as to face the opening 301. A part of, for example, a loop-shaped flat plate type heat pipe 321 constituting the phase change flow path is disposed to face each other. Examples of the flat plate heat pipe 321 include pipes such as “1 mm-thick micro heat pipe” disclosed in Furukawa Electric Time Report No. 114 and “heat pipe excellent in thermal conductivity” manufactured by Nippon Metal Industry Co., Ltd. A flat plate or rod-shaped member having a so-called wick on the inner wall is used.

  The condensing part (heat radiation side) of the heat pipe 321 is provided with a pump connection member using a metal material having high thermal conductivity such as aluminum or stainless steel described later. Moreover, although the heat pipe 321 uses copper or a copper alloy, it can be replaced with an insert-molded product by PPS resin filled with alumina powder, glass fiber, or carbon fiber in granular graphite due to plasticity, mass productivity, and the like. is there.

  Further, a heat conductive rubber material 339 containing a latent heat storage material (not shown) or bonded with a latent heat storage material sheet (not shown) is thermally coupled on the element support member 320 as shown in FIG. A second temperature sensor 143B is provided in the thermally conductive rubber material 339. The second temperature sensor 143B is solder-bonded to the FPC board 300 and connected to the CPU 141. With such a configuration, the temperature of the latent heat storage material 104a can be indirectly measured by the second temperature sensor 143B. And various control (detailed in 1st Embodiment) by CPU141 based on this measurement result is attained.

  The element support member 320 has, for example, a recess (not shown) formed at a position where the heat pipe 321 is disposed, and a double-sided tape or the like is interposed in the recess (not shown) with, for example, a heat conductive material having excellent thermal conductivity. A part of the heat pipe 321 is accommodated to be positioned with respect to each other. Thereby, the heat pipe 321 can be easily assembled and arranged with respect to the element support member 320. When the PPS resin insert-molded product is used for the element support member 320, the heat pipe 321 is directly embedded in the element support member 320. By using a double-sided tape or the like, the heat pipe 321 can be used. The thermal coupling (heat conduction) to the element support member 320 is significantly improved.

  Here, heat from the image sensor 121 is transmitted to the element support member 320 and the heat pipe 321. Then, this heat is temporarily absorbed by the latent heat storage material 104a of the frame member 314, and the latent heat storage material 104a is melted and solidified below the use limit of the image sensor 121, for example, around 60 to 80 ° C. as a melting point. The member 314 is kept at a constant temperature. As a result, the temperature of the FPC board 300 including the image sensor 121 can be prevented from rising rapidly.

  The heat pipe 321 is thermally coupled, for example, by the heat dissipation member 322 supporting the periphery of the opening 301 of the element support member 320 on the heat absorption side. For this heat pipe 321, pure water, alcohol, or a known latent heat storage material or a microcapsule dispersion containing a reversible thermochromic pigment capable of starting and storing color at a high temperature (for example, 59 ° C.) is used. The working fluid is accommodated, absorbs heat radiated from the back-side insulating sheet 128 of the image sensor 121, transfers the heat by phase change, and performs heat dissipation by reversing the phase change.

  The heat radiating member 322 is formed of, for example, a synthetic resin material having excellent thermal conductivity similar to that of the frame member 314, and the latent heat storage material 104a changing in phase is thermally formed therein by a technique such as insert molding. Combined and arranged. The heat radiating member 322 is attached to the element support member 320 using an adhesive or a screw member. As a result, when heat from the imaging element 121 is transferred from the heat pipe 321 and the element support member 320, the heat dissipation member 322 radiates heat in a state where the latent heat storage material 104a once absorbs heat and is held at a constant temperature. Execute.

  In addition, the heat pipe 321 includes a heat circulating member in a known synthetic resin pump or pump and a heat radiating member 322 disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-28068. A piezoelectric pump (or a trochoid type small pump) 23, which is one of the forced air cooling devices interposed, is disposed, and the pump connection is made via the piezoelectric pump 323 that is thermally disconnected from the heat radiating member 322. There is a member 331. This pump connection member 331 becomes a condensing part.

  Here, when the wick described above is formed in the condensing unit, for example, the piezoelectric pump 323 can be omitted. In this case, if the pump connection member 331 becomes a condensing part of the heat pipe 321 and a heat insulating member (replacement of the piezoelectric pump 323) is interposed between the condensing part and the heat radiating member 322, the heat of the heat radiating member 322 is connected to the pump. It is possible to suppress heat conduction to the member 331.

  Further, the heat pipe 321 is configured to circulate the working fluid between the heat absorption side and the heat dissipation side by utilizing the phase change without disposing the piezoelectric pump 323 as the fluid circulation means. May be.

  The heat pipe 321 has a heat absorbing material 335 that is a member that absorbs infrared rays, for example, bonded to an outer wall facing the back-side insulating sheet 128 of the imaging element 121. The heat absorbing material 335 is formed of an aluminum alloy material, and has a black alumite treatment, spline processing on the surface side, or a PPS resin filled with the above-mentioned granular graphite and carbon or glass fiber, and a graining treatment for scattering infrared rays. If the heat absorption surface 334 having an emissivity of 0.9 or more, a low infrared reflectance, and a high heat absorption property is formed by performing an embossing (regular or irregular uneven shape) treatment or the like, an even better effect is obtained. Be expected. Accordingly, the heat pipe 321 efficiently absorbs heat that is transferred by heat dissipation and convection from the back-side insulating sheet 128 of the image sensor 121 through the opening 301 of the element support member 320 by the heat absorption surface 334. Highly efficient phase change (vaporization) by working fluid can be realized.

  Here, when the heat from the back side insulating sheet 128 of the image sensor 121 is transferred to the heat pipe 321 by heat conduction, for example, heat absorption of the back side insulating sheet 128 and the heat pipe 321 is performed using a heat conductive rubber material. The surface 334 is configured to be thermally coupled. As a result, the heat pipe 321 has the same length as the back-side insulating sheet 128 of the image sensor 121, is heat-transferred by heat conduction, and can further improve the cooling efficiency.

  Further, the back-side insulating sheet 128 of the image sensor 121 may be configured to be connected to the outer wall of the heat pipe 321.

  For example, the pump connection member 331 that is thermally disconnected from the heat radiating member 322 is thermally coupled to the heat pipe 321 on the heat radiating side. As a result, the heat pipe 321 has a sufficient phase change area on the heat absorption side and the heat dissipation side, and can efficiently absorb and dissipate the heat transferred by the heat convection and heat radiation. It becomes possible to realize highly efficient cooling of the element 121.

  In addition, the FPC board 300 is thermally coupled to the element support member 320, and heat generated in the imaging element 121 and heat of other electronic components mounted on the FPC board 300 are transmitted via the FPC board 300. Heat is transferred by heat conduction. The heat conducted to the element support member 320 is transferred from the element support member 320 to an equipment casing (not shown) to be dissipated.

  With the above configuration, the heat generated in the image sensor 121 is transferred from the back insulating sheet 128 to the heat absorption surface 334 of the heat pipe 321 by convection and heat conduction, and is also transferred to the element support member 320 by heat conduction. The Here, the heat pipe 321 absorbs heat at the heat absorption surface 334, the working fluid is phase-changed and vaporized, moves into the flow path, is liquefied, and dissipates heat. The heat of 121 is exhausted and cooled.

  At the same time, the heat generated in the image sensor 121 is transferred to the element support member 320 by heat conduction, and is exhausted to the device housing (not shown) or the like through the element support member 320 to be radiated. Thereby, highly efficient thermal control of the image sensor is possible.

  As described above, the imaging module 8 includes the heat radiation member 322 that is thermally coupled to the FPC board 300 and the image sensor 121 and is formed of a synthetic resin material having excellent thermal conductivity. On the other hand, the latent heat storage material 104a that changes phase by insert molding is configured to be thermally coupled.

  According to this, when the image sensor 121 is driven, the heat is transferred from the rear insulating sheet 128 through the opening 311 of the FPC board 300 to the heat radiating member 322, and the latent heat storage of the heat radiating member 322 is performed. The material 104a undergoes a phase change. Thereby, the heat radiating member 322 is maintained at a constant temperature and radiates the heat transferred to thermally control the image sensor 121 to a desired value. As a result, it is possible to efficiently dissipate the heat of the printed wiring board including the heat of the image sensor through the resin heat dissipating member with a simple configuration, realizing high-efficiency cooling, and manufacturing including the thermal design of the module The degree of freedom can be improved.

  By the way, a connection flexible printed circuit board (not shown; hereinafter referred to as a connection FPC) is attached and connected to the non-imaging surface side of the image sensor 121 and is connected to the printed circuit board 140 of the image pickup circuit via connectors 139A and 139B. .

  Here, the printed circuit board 140 includes connectors 139A and 139B for connection to the connection FPC (not shown), a control circuit unit (CPU) 141, an AFEIC element 42 as an image processing circuit component, and the latent heat. There is provided a first temperature sensor 143A soldered to a surface facing the heat storage material sheet 122a.

  Here, as shown in FIG. 5, the imaging module 8 having two temperature sensors, that is, the first temperature sensor 143A and the second temperature sensor 143B has been described as an example. One is enough.

  Hereinafter, advantages of the first temperature sensor 143A and the second temperature sensor 143B will be described.

(1) Advantages of the first temperature sensor 143A • Easy assembly.

  However, since it is not near the latent heat storage material 104a, a predetermined offset must be added to the measured temperature.

(2) Advantages of the second temperature sensor 143B-Since the heat sensor is located in the vicinity of the latent heat storage material 104a, the measurement accuracy of the temperature of the latent heat storage material 104a is high. Therefore, as in the case of the first temperature sensor 143A described above, it is not necessary to add a predetermined offset to the measured temperature, and a memory for storing the offset value is not required.

  However, the first temperature sensor 143A is more easily assembled.

  According to the electronic camera according to the second embodiment, the same operation control as that of the electronic camera according to the first embodiment described above with reference to FIG. 3 is adopted. The cooling efficiency of the image sensor can be further increased as compared with the electronic camera according to the first embodiment.

Here, the distance between the image sensor 121 and the latent heat storage material 104a disposed on the heat radiating member 322 is d1, and the first temperature disposed in the vicinity of the image sensor 121 and the element support member 320. When the distance from the sensor 143A or the second temperature sensor 143B is d2, the d1 and the d2 are
d1 ≦ d2 (Formula 6)
It is preferable from the viewpoint of ease of assembly.

  By the way, the temperature rise due to conduction heat, radiant heat, and the like caused by high-speed driving of the image sensor 121 is provided on the printed circuit board 140 from the element support member 320 and the heat dissipation member 322 through a gap (space). Provided by being included in the first temperature sensor 143A or a heat conductive rubber material 339 (not shown but containing a latent heat storage material or a latent heat storage material sheet is bonded) bonded to the element support member 320. Measurement is performed by temperature detection by the second temperature sensor 143B.

  Specifically, the temperature of the imaging element 121 rises as shown in FIG. 4 on the back-side insulating sheet 128 provided immediately below. The temperature T2 is reached at time t1 when the melting of the latent heat storage material 104a is completed. Here, during the melting of the latent heat storage material 104a, the temperature of the element support member 320 and the heat dissipation member 322 is maintained at a substantially constant temperature (melting temperature), and the temperature of the imaging element 121 is also maintained at the melting temperature. Is done. When the temperature becomes equal to or higher than T3, the piezoelectric pump 323 is driven and controlled so that the working fluid is forcedly circulated so as not to stop. Thereby, the temperature in the vicinity of the image sensor 121 is effectively cooled, and the heat of the heat storage latent heat agent 104a is released to the space of the gap. When the temperature in the vicinity of the image sensor 121 decreases as at time t3 shown in FIG. 4, a phase change from liquid to solid occurs in the latent heat storage material 104a.

  As described above, according to the second embodiment, the method for cooling the image sensor according to the first embodiment described above, the method for suppressing the heat generation of the image sensor, which has higher cooling efficiency than the electronic camera, and the image sensor. A cooling method and an electronic camera can be provided.

[Third Embodiment]
Hereinafter, an image sensor heat generation suppressing method, an image sensor cooling method, and an electronic camera according to a third embodiment of the present invention will be described.

  For the sake of convenience of explanation, explanations common to the image sensor heat generation suppression method, image sensor cooling method, and electronic camera according to the first embodiment will be omitted, and differences will be described.

  FIG. 6 is a cross-sectional view showing a configuration of the imaging module 8 in the electronic camera according to the third embodiment.

  The module structure shown in FIG. 6 is mounted and electrically connected to the FPC board 411 so that the back-side insulating sheet 128 of the bare chip type image pickup device 121 is accommodated in the opening 414 provided in the FPC board 411. On the back side of the opening 414 of the FPC board 411, a loop-shaped flat plate heat pipe 421 constituting the phase change flow path (for example, the outer shape is a loop shape, the pipe width is smaller than the dimension of the image sensor 121, A part (heat absorption part) of the back side insulating sheet 128 is disposed so as to face the back side insulating sheet 128. On the back side of the FPC board 411, a cylindrical element support insert-molded with a synthetic resin material having excellent thermal conductivity such as PPS resin filled with alumina powder, glass fiber or carbon fiber in granular graphite is supported. A member 430 is disposed and one end thereof is thermally coupled.

  In addition, the space between the back-side insulating sheet 128 of the image sensor 121 and a first heat radiation member 432 described later is output from the second temperature sensor 408 that detects the ambient temperature in the vicinity of the image sensor 121 and the image sensor 121. Electronic components such as AFEIC elements for holding and controlling gain of image signals are arranged.

  The heat pipe 421 is subjected to black alumite treatment or the like at a portion of the outer peripheral portion facing the back-side insulating sheet 128 to form a heat absorption surface 422. The heat absorption surface 422 is disconnected from the opening 401 of the element support member 430 by heat conduction, and heat from the back side insulating sheet 128 of the image sensor 121 is transferred by heat convection and heat radiation. . A part of both sides of the heat absorption surface 422 of the heat pipe 421 is supported by being bonded to the element support member 430 via an adhesive 494 and thermally coupled by heat conduction.

  The element support member 430 is provided with a fin guide groove 402 on an inner wall portion thereof, and the fin guide groove 402 includes first and second heat radiation members 432 constituting a heat radiation member sandwiching a phase change latent heat storage material. , 433 are movably accommodated. The first and second heat radiating members 432 and 433 are, for example, PPS in which glass fiber, carbon resin, or the like is filled in a synthetic resin material having excellent thermal conductivity mixed with a filler such as metal oxide or ceramic. (Polyphenylene sulfide) resin or the like.

  The latent heat storage material 104a is filled with an organic heat storage material such as paraffin, carbon fiber made of a material that easily conducts heat, or a paraffin or other organic heat storage material filled with a gel that can be held in a solid form even at a melting temperature or higher. It has a so-called heat storage microcapsule structure in which a core material such as paraffin or inorganic hydrated salt is covered with a container, and can be melted and solidified by changing the phase at a temperature lower than the use limit temperature of the image sensor 121, for example, 60 to 80 ° C. Is formed. Thereby, the latent heat storage material 104a holds the first and second heat radiating members 432 and 433 at a constant temperature of 60 to 80 ° C. which is equal to or lower than the use limit temperature of the image sensor 121, and sets the image sensor 121 to a desired value. Control heat.

  The first and second heat radiating members 432 and 433 are provided with a plurality of fins 441 and 442 facing each other, and are thermally coupled to each other via the latent heat storage material 104a. Of these, the second heat dissipating member 433 is provided with a mounting portion 456 having a through hole 455 at one end thereof, and the through hole 455 of this mounting portion 456 is a screw hole (not shown) provided in the element support member 430. Is placed on the element support member 430.

  A spacer member 434 having a through hole 461 is stacked on the mounting portion 456, and a part of the FPC board 411 that is folded back so as to wrap the element support member 430 is placed on the spacer member 434. Is placed. On the FPC board 411, for example, a pressing member 435 made of stainless steel or aluminum is stacked and arranged.

  The FPC board 411 and the pressing member 435 are provided with through holes 471 and 451 corresponding to the through holes 461 of the spacer member 434, and screw members 436 are provided in the through holes 451, 471, 341 and 455, respectively. The element support member 430 is inserted and screwed into screw holes (not shown) drilled on both sides of the heat pipe 421 and is thermally coupled to the element support member 430 and positioned.

  In addition, for example, a first temperature sensor 437 is mounted on the FPC board 411, and the temperature in the first and second heat radiating members 432 and 433 (the temperature of the latent heat storage material 104 a) is detected by the temperature sensor 437. The The first temperature sensor 437 detects the ambient temperature (the temperature of the latent heat storage material 104a) in the first and second heat radiating members 432 and 433 and outputs it to a CPU (not shown). This CPU is provided on a printed circuit board (not shown) to which an FPC board 411 is connected via a connector (not shown). And this control part performs various control demonstrated in the said 1st Embodiment based on the detection signal of the 1st temperature sensor 437. FIG.

  Further, the image pickup device 121 includes, for example, a glass fiber or a glass fiber on the periphery of the image pickup surface, for example, granular graphite constituting the camera shake prevention mechanism shown in FIGS. 4 and 5 of Japanese Patent Application No. 2006-222709. The holding member 439 supported by the moving frame 438 insert-molded with PPS resin filled with carbon fiber is engaged, and the surface direction thereof is maintained constant, and the two-dimensionally passes through the moving frame 438. By being moved, so-called camera shake correction is possible. The moving frame 438 is thermally coupled to the pressing member 439 through, for example, a coupling unit (not shown), and the heat accompanying the driving is exhausted through the coupling unit.

  Note that, for example, during continuous shooting and live view mode, when the image sensor 121 is driven at high speed, the temperature in the vicinity of the insulating sheet 128 disposed immediately below the back surface of the image sensor 121 increases, and the latent heat storage material When 104a reaches, for example, 48 ° C. or 58 ° C. or higher, melting starts and heat is stored. The stored heat is received and detected by the temperature sensor 437 as conduction heat or radiant heat from the second heat radiation member 433.

  Incidentally, reference numeral 491 denotes a latent heat storage material sheet. The heat generated in the vicinity of the image sensor 121 is partly stored by the latent heat storage material sheet 491 through each member provided on the FPC board 411. As a result, it is possible to eliminate the need for a separate space for disposing a heat sink for dissipating heat generated in the vicinity of the image sensor 121.

  According to the electronic camera according to the third embodiment, the same operation control as that of the electronic camera according to the first embodiment described above with reference to FIG. 3 is adopted. The cooling efficiency of the image sensor can be further increased as compared with the electronic camera according to the first embodiment.

Here, in the electronic camera according to the third embodiment, the latent heat storage material 104a, the first temperature sensor 437, and the second temperature sensor 408 are arranged in the moving frame 438 which is a movable member. When the distance between the image sensor 121 and the latent heat storage material 104a is d3, and the distance between the image sensor 121 and the first temperature sensor 437 or the second temperature sensor 408 is d4, the d3 and the d4 are
d3 ≦ d4 (Expression 7)
It is preferable from the viewpoint of ease of assembly.

  Hereinafter, advantages of the first temperature sensor 437 and the second temperature sensor 408 will be described.

(1) Advantages of the first temperature sensor 437 and the second temperature sensor 408-Easy assembly.

  However, since it is not near the latent heat storage material 104a, a predetermined offset must be added to the measured temperature.

  However, the first temperature sensor 437 is easier to assemble.

  As described above, according to the third embodiment, the imaging element cooling method and the imaging element heat generation suppression method, the imaging element cooling efficiency higher than that of the above-described imaging element cooling method and electronic camera according to the first embodiment, and the imaging element. A cooling method and an electronic camera can be provided.

  Further, according to the third embodiment, the moving frame 438 can be reduced in weight by the above-described configuration, so that power consumption can be suppressed. In addition, since a TG (timing generator) and an AFEIC element can be arranged immediately below the image sensor 121, the connection line between the image sensor 121 and these electronic components can be shortened, and is less susceptible to external noise. Further, as can be seen from the above-described configuration, the assembly process of the imaging module can be simplified.

[Fourth Embodiment]
Hereinafter, an image sensor heat generation suppression method, an image sensor cooling method, and an electronic camera according to a fourth embodiment of the present invention will be described.

  For the sake of convenience of explanation, explanations common to the image sensor heat generation suppression method, image sensor cooling method, and electronic camera according to the first embodiment will be omitted, and differences will be described.

  FIG. 7 is a cross-sectional view showing the configuration of the imaging module 8 in the electronic camera according to the fourth embodiment.

  In the module structure shown in FIG. 7, the imaging device 121a is, for example, a bare chip type imaging device 121a, and a so-called hard type printed wiring board 561 is filled with granular graphite, carbon fiber, amorphous (glass) fiber, or the like. It is mounted via an image sensor support member 562 that is insert-molded with PPS resin. The imaging element support member 562 is provided with the phase change latent heat storage material 104a that is thermally coupled by insert molding. This latent heat storage material 104a has, for example, a so-called heat storage microcapsule structure in which an organic heat storage material such as paraffin or paraffin filled with carbon fiber, or a core material such as paraffin or inorganic hydrate salt filled with a polymer is covered with a container. However, it is formed to be capable of melting and solidifying by changing the phase at a temperature lower than the use limit temperature of the image sensor 121, for example, 60 to 80 ° C. As a result, the latent heat storage material 104 a holds the image sensor supporting member 562 at a constant temperature of 60 to 80 ° C., which is lower than the use limit temperature of the image sensor 121.

  Positioning pins 621 project from the imaging element support member 562 so as to face the printed wiring board 561, and the positioning pins 621 are inserted into the insertion holes 611 of the printed wiring board 561 so as to be positioned and assembled. . As a result, the image sensor 121a can be assembled with its light receiving surface aligned with the imaging lens in the optical axis.

  The image sensor supporting member 562 is provided with an opening 622 and an opening 601. A lead terminal 502a protruding from the back side of the image sensor 121a is inserted through the image sensor supporting member 562. The lead terminal 502a is electrically connected to the printed wiring board 561 by soldering or the like.

  On the back side of the printed wiring board 561, for example, a backlight member 563 and an LCD (Liquid Crystal Display) 564 that constitute an electronic camera are assembled using a fixture 566 and a screw member 567. It is attached. Further, the back side insulating sheet 128a of the image sensor 121a and the opening 622 and the opening 601 provided in the image sensor support member 562 are not provided, and the thermal coupling between the image sensor 121a and the image sensor support member 562 is a heat conduction. It can be only.

  The shield member 565 is formed of aluminum or the like having good thermal conductivity, and is assembled by being thermally coupled to the rear cover 568 constituting the electronic camera that is, for example, a device housing by thermal conduction. The rear cover 568 forms a camera housing with a front cover and a middle frame (not shown).

  The printed wiring board 561 is provided with openings 612 and notches 613 at predetermined intervals corresponding to the heat pipes 569. A loop-shaped heat pipe 569 constituting a phase change flow path is inserted into the opening 612 and the notch 613, and the heat pipe 569 is piped from the upper surface side to the back surface side of the printed wiring board 561.

  This heat pipe 569 is, for example, a heat pipe excellent in thermal conductivity made by the Nippon Metal Industry Co., Ltd. in which a wick is formed. When heat is applied from the back side of the image sensor 121a to the heat absorption side, The working fluid takes heat away by capillary action and evaporates, increasing the atmospheric pressure and utilizing the phase change flowing to the lower atmospheric pressure side at the other end side. On the back side of the printed wiring board 561, aluminum having good thermal conductivity is used. Are supported by the shield member 565 via a plurality of pipe support members 570 formed by, for example, and are thermally coupled by heat conduction.

  Here, in the heat pipe 569 having a capillary action called wick on the inner wall, the condensed working fluid is again refluxed to the heat absorption side by the capillary of the wick, and this evaporation, condensation, and reflux cycle is executed. The temperature rise of 121a can be suppressed. A temperature sensor 571 is mounted on the printed wiring board 561 by using, for example, a space between the pipe support members 570 (supported with a rubber material having a high thermal conductivity (not shown)). 711 is electrically connected.

  Here, when heat from the back-side insulating sheet 128a of the image sensor 121a is transferred by convection and heat radiation through the opening 601 and the opening 622 of the image sensor support member 562, the heat pipe 569 receives the working fluid. It absorbs heat and vaporizes due to the phase change, and is liquefied and exhausted on the heat dissipation side.

  Note that a piezoelectric pump 572 may be connected between the pipe support members 570 of the heat pipe 569 instead of the temperature sensor 571 as shown in FIG. Further, the heat pipe 569 is configured such that the vicinity of the portion supported by the pipe support member 570 is connected by piping using, for example, a bellows-type connection tube 573 that can be expanded and contracted in the axial direction. Can be performed.

  In addition, heat generated by electronic components such as a CPU (central processing unit) and AFEIC elements mounted on the printed wiring board 561 is generated between the back side of the component mounting portion of the printed wiring board 561 and the shield member 565. Thermally coupled to the shield member 565 directly through a heat conductive material such as a silicon sheet. As a result, the heat of the electronic component mounted on the printed wiring board 561 is suppressed from being conducted to the imaging element support member 562 and is efficiently radiated through the shield member 565, and the configuration of the imaging element support member 562 is simplified. Can be achieved.

  The heat pipe 569 may be configured to form a heat absorption surface by performing black alumite treatment or the like on the outer peripheral portion facing the opening 622 of the imaging element support member 562. This makes it possible to promote heat transfer to the heat pipe 569 due to heat convection and heat radiation from the image sensor 121a.

  According to the electronic camera according to the fourth embodiment, the same operation control as that of the electronic camera according to the first embodiment described above with reference to FIG. 3 is adopted. The cooling efficiency of the image sensor can be further increased as compared with the electronic camera according to the first embodiment.

In the electronic camera according to the fourth embodiment, a latent heat storage material 104a is joined to the shield member 565, and a temperature sensor 571 is disposed on the printed wiring board 561 facing the latent heat storage material 104a. Here, the distance between the image sensor 121 and the latent heat storage material 104a disposed on the shield member 565 is d5, and the temperature sensor 571 disposed on the image sensor 121 and the printed wiring board 561. Where d6 is d6 and d6 is
d5 <d6 (Formula 8)
It is preferable from the viewpoint of ease of assembly. The driving of the piezoelectric pump 572 to which the heat pipe 569 is connected is the same as that of the second embodiment, and will not be described.

  As described above, according to the fourth embodiment, the imaging element heat generation suppression method, the imaging element cooling method, and the imaging element having higher cooling efficiency than the electronic camera according to the first embodiment described above. A cooling method and an electronic camera can be provided.

  As mentioned above, although this invention was demonstrated based on 1st Embodiment thru | or 4th Embodiment, this invention is not limited to embodiment mentioned above, A various deformation | transformation and application are within the range of the summary of this invention. Of course it is possible.

(Appendix)
For example, the invention having the following configuration can be extracted from the specific embodiment.

(1)
A temperature measuring step for measuring by a temperature sensor based on a phase change temperature of a predetermined latent heat storage material arranged in the vicinity of the image sensor;
A comparison step of comparing the measured temperature acquired in the temperature measurement step with a predetermined threshold;
Based on the comparison result in the comparison step, an operation start step for starting driving the drive circuit of the forced air cooling device;
A cooling method for an image sensor, comprising:

(2)
A latent heat storage material disposed in the vicinity of the image sensor;
A temperature sensor for measuring a phase change temperature of the latent heat storage material;
A comparison means for comparing the temperature measured by the temperature measurement sensor with a predetermined threshold;
Control means for starting driving of the drive circuit of the forced air cooling device based on the comparison result by the comparison means;
An electronic camera comprising:

(3)
The electronic camera according to (2), wherein the forced air cooling device is a pump or a fan to which a heat pipe is connected.

  Further, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the 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 column of the effect of the invention Can be extracted as an invention.

1 is a longitudinal sectional view showing a main configuration of an electronic camera according to a first embodiment of the present invention. 1 is a diagram showing an external configuration of an electronic camera according to a first embodiment of the present invention. 1 is a block diagram showing an electric control unit of an electronic camera according to a first embodiment of the present invention. The figure which shows the flowchart which shows the operation control by CPU in the electronic camera which concerns on 1st Embodiment of this invention. The figure which shows the graph showing the timing of the switching of the frame rate of a live view display in the live view mode, and the start / stop of fan drive. Sectional drawing which shows the structure of the image pick-up element module in the electronic camera which concerns on 2nd Embodiment of this invention. Sectional drawing which shows the structure of the image pick-up element module in the electronic camera which concerns on 3rd Embodiment of this invention. Sectional drawing which shows the structure of the image pick-up element module in the electronic camera which concerns on 4th Embodiment of this invention. Sectional drawing which shows the modification of a structure of the image pick-up element module in the electronic camera which concerns on 4th Embodiment of this invention.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1A ... Camera body, 1B ... Interchangeable lens barrel, 3 ... Body side mount part, 2 ... Camera exterior, 4a ... Center opening part, 4 ... Main body structure, 4b ... Reinforcement rib, 5 ... Main mirror, 6 ... Focal Planar shutter, 8 ... Imaging module, 9 ... Focusing screen, 10 ... Pentaprism, 11 ... Eyepiece, 12 ... LCD, 13 ... Monitor display window, 14 ... Body side mount, 23 ... Piezoelectric pump, 42 ... AFEIC element 51 ... Lens attachment / detachment button 52 ... Grip part 53 ... Shutter button 54 ... Exposure compensation button 55 ... Mode dial 56 ... Control dial 57 ... Optical finder 58 ... Hot shoe 71 ... Cooling fan 81 87 ... Intake hole, 82 ... Exhaust hole, 104a ... Latent heat storage material 119 ... Dust-proof mechanism 121, 121a ... Imaging device 122 ... Imaging device support plate 122a ... Latent heat storage material sheet 123 ... Base 124 ... Dust-proof glass 125 ... Optical filter 126 ... Piezoelectric device 127 ... Support member, 128 ... Insulating sheet, 128a ... Back side insulating sheet, 130 ... Imaging element cooling unit, 135 ... Connection flexible printed circuit board, 139A, 139B ... Connector, 140 ... Printed circuit board, 141 ... CPU, 143A ... First temperature sensor , 143B ... second temperature sensor, 201 ... fan drive motor, 203 ... imaging element shift drive motor, 209 ... shutter drive motor, 210 ... main mirror drive motor, 211 ... shutter control magnet, 216 ... range sensor, 224 ... focusing Driving mode 230: Fan drive circuit, 231: Image sensor shift drive circuit, 232 ... Shutter charge drive circuit, 233 ... Main mirror drive circuit, 234 ... Shutter drive circuit, 236 ... Distance measuring circuit, 237 ... Focusing drive circuit, 238 ... Image Processing circuit 239 ... Image recording unit 241 ... LCD drive circuit 243 ... 1st release switch 244 ... 2nd release switch 245 ... Bus line 246 ... ROM 300 ... Flexible printed circuit board 301 ... Opening part 302 ... Lead terminal, 311 ... Opening for heat dissipation, 312 ... Rubber frame, 313 ... Optical low-pass filter, 314 ... Frame member, 315 ... Holding part, 317 ... Transparent glass substrate, 318 ... Excitation member, 319 ... Pressing member, 320 ... Element support member, 321... Heat Pipe, 322 ... Heat dissipation member, 323 ... Piezoelectric pump, 331 ... Pump connection member, 333 ... Adhesive, 334 ... Heat absorption surface, 335 ... Heat absorption material, 339 ... Thermally conductive rubber material, 341 ... Reinforcement rib, 401 DESCRIPTION OF SYMBOLS ... Opening part 402 ... Fin guide groove 408 ... Temperature sensor 411 ... FPC board | substrate 414 ... Opening part 421 ... Heat pipe 422 ... Heat absorption surface 430 ... Element support member 432 ... 1st thermal radiation member, 432, 433 ... second heat radiating member, 433 ... second heat radiating member, 494 ... adhesive, 434 ... spacer member, 436 ... screw member, 437 ... temperature sensor, 438 ... moving frame, 441.442 ... fin, 451 .471 ... Through hole, 455,461 ... Through hole, 471,451 ... Through hole, 491 ... Latent heat storage material sheet, 502a ... Lead Child, 561 ... printed wiring board, 562 ... imaging element support member, 563 ... backlight, 564 ... LCD, 565 ... shield member, 567 ... screw member, 568 ... rear cover, 569 ... heat pipe, 570 ... pipe support member, 571: Temperature sensor, 572: Piezoelectric pump, 573: Bellows connection pipe, 601 ... Opening, 611 ... Insertion hole, 612 ... Opening, 613 ... Notch, 621 ... Pin, 622 ... Opening, 711 ... Lead line.

Claims (8)

A temperature measurement step of measuring by a temperature sensor with reference to a predetermined temperature of the latent heat storage material arranged in the vicinity of the image sensor;
A comparison step of comparing the measurement temperature acquired in the temperature measurement step with a phase change temperature of the latent heat storage material and a predetermined threshold;
Based on the comparison result in the comparison step, a switching step for switching the cycle of the operation clock in the live view mode,
A method for suppressing heat generation of an image sensor, comprising: A temperature measurement step for measuring with a temperature sensor based on the phase change temperature of the latent heat storage material arranged in the vicinity of the image sensor;
A comparison step of comparing the measured temperature acquired in the temperature measurement step with a predetermined threshold;
The predetermined threshold values are a first threshold value T1, a second threshold value T2, and a third threshold value T3. When the measured temperature acquired in the temperature measuring step is t,
In the comparison step,
T1 <t ≦ T2
If the measured temperature t is determined to satisfy the above condition, the operation clock cycle of the image sensor is not switched in the switching step,
t ≦ T1
If it is determined that the condition is satisfied, the operation clock cycle of the image sensor is set to the basic clock cycle in the switching step,
T2 <t
Is determined to satisfy the measured temperature t, in the switching step, the period of the operation clock of the image sensor is set to twice the period of the basic clock,
T3 <t
When the measured temperature t is determined to satisfy the above condition, in the switching step, the period of the operation clock of the image sensor is set to twice the period of the basic clock, and the forced air cooling device is driven. A method for cooling an image sensor.   The method for cooling an imaging element according to claim 2, wherein a distance between the imaging element and the latent heat storage material is shorter than a distance between the imaging element and the temperature sensor. The temperature sensor is
The cooling method for an image pickup device according to claim 2, wherein the image pickup device is disposed on the printed board or between the printed board and the LCD shield plate. An image sensor;
A latent heat storage material and a temperature sensor disposed in the vicinity of the image sensor;
Comparison means for comparing the temperature measured by the temperature sensor with the phase change temperature of the latent heat storage material,
Control means for switching the period of the operation clock in the live view mode based on the comparison result by the comparison means,
An electronic camera comprising: A latent heat storage material disposed in the vicinity of the image sensor;
A temperature sensor for measuring a phase change temperature of the latent heat storage material;
A comparison means for comparing the temperature measured by the temperature measurement sensor with a predetermined threshold;
The predetermined threshold values are a first threshold value T1, a second threshold value T2, and a third threshold value T3, and when the measured temperature measured in the temperature measuring step is t,
The measured temperature t is
T1 <t ≦ T2
If it is determined by the comparison means that the condition is satisfied, the control means does not switch the cycle of the operation clock of the image sensor,
t ≦ T1
When it is determined by the comparison means that the condition is satisfied, the control means sets the period of the operation clock of the image sensor to the period of the basic clock,
T2 <t
When it is determined by the comparison means that the condition is satisfied, the control means sets the cycle of the operation clock of the image sensor to a cycle that is twice the cycle of the basic clock,
T3 <t
If it is determined by the comparison means that the condition is satisfied, the control means sets the period of the operation clock of the image sensor to twice the period of the basic clock and drives the forced air cooling device in the switching step. An electronic camera characterized by that.   The electronic camera according to claim 6, wherein a distance between the image sensor and the latent heat storage material is shorter than a distance between the image sensor and the temperature sensor. The temperature sensor is
The electronic camera according to claim 6, wherein the electronic camera is disposed on the printed board or between the printed board and the LCD shield plate.

Images