JP2008011233A - Photographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cool an image sensor without causing dew condensation. <P>SOLUTION: An internal heat sink holding the image sensor is cooled with a Peltier element. An internal heat sink is attached on a heat discharging surface of the Peltier element. An inside temperature sensor is provided in the inside of the internal heat sink, and an outside air temperature sensor for measuring the outside air temperature is provided on the external heat sink. If the inside temperature which is to be measured with the inside temperature sensor exceeds a predetermined temperature Ts, the Peltier element and a fan are operated to start cooling. When the inside temperature is lowered to the outside air temperature which is to be measured with the outside air temperature sensor during cooling, the cooling is stopped. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photographing apparatus incorporating an image sensor.

  2. Description of the Related Art A digital camera that converts a captured image taken using an image sensor into digital image data and records it on a recording medium such as a built-in memory or a memory card has become widespread. In addition, in order to facilitate handling of an interchangeable lens digital camera, a lens barrel with a built-in circuit such as an image sensor is known. In this case, the room in which the image sensor is arranged can be sealed, so that the problem that dust adheres to the image sensor can be solved. However, in the type in which the image sensor is built in the lens barrel side, the internal temperature rises because the image sensor and a circuit for driving the image sensor are arranged in a narrow space in the lens barrel. There was a problem that the performance of each part deteriorated. In particular, an image sensor which is a semiconductor product has a problem that noise increases due to temperature rise.

In order to solve the above problems, in Patent Documents 1 and 2, the CCD image sensor is controlled to be cooled by a Peltier element and cooled until the temperature of the CCD image sensor becomes lower than the set temperature. In this case, condensation may occur in the image sensor. Therefore, the CCD image sensor is cooled in the container in which the CCD image sensor is stored so that the package is cooler than the element itself, thereby causing condensation on the package and preventing the element itself from being condensed. Those are known (for example, see Patent Document 3). Further, it is known that a CCD image sensor is accommodated in a sealed space, and a dry gas such as nitrogen gas is sealed in the sealed space so that no condensation occurs on the CCD image sensor when cooled (for example, (See Patent Document 4).
JP 2000-228734 A JP 2000-228736 A JP-A-9-162379 JP 2004-260704 A

  However, in the case where dew condensation occurs in a container containing an image sensor as in Patent Document 3, a mechanism for treating water droplets generated by the dew condensation and measures to prevent the circuit from being short-circuited by the water droplets are necessary. There was a problem of becoming. Further, in the method using dry gas as in Patent Document 4, it is necessary to maintain the space in which the image sensor is accommodated in a very high sealed state, which causes an increase in the number of parts and special manufacturing for injecting dry gas. There was a problem that a process was necessary.

  An object of the present invention is to provide a photographing apparatus capable of cooling an image sensor while preventing condensation with a simple structure.

  In order to achieve the above object, in the photographing apparatus according to claim 1, a housing having thermal conductivity for holding the image sensor therein, and a temperature inside or in the housing in which the image sensor is arranged are measured. An internal temperature sensor that measures the external temperature, a Peltier element having an endothermic surface attached to the outer surface of the housing, a heat sink attached to the waste heat surface of the Peltier element, A cooling control means for comparing the internal temperature measured by the internal temperature sensor with the outside air temperature measured by the outside air temperature sensor, and driving and cooling the Peltier element only when the internal temperature is higher than the outside air temperature; It is provided.

  3. The photographing apparatus according to claim 2, wherein a housing having heat conductivity for holding the image sensor therein, an internal temperature sensor for measuring the temperature of the inside of the housing in which the image sensor is arranged or the housing, and the housing. A Peltier element with an endothermic surface attached to the outer surface of the body, a heat sink attached to the waste heat surface of the Peltier element, and a temperature measured by the internal temperature sensor immediately after the power is turned on, as a reference temperature And a cooling control means for comparing the reference temperature with the internal temperature measured by the internal temperature sensor and driving and cooling the Peltier element only when the internal temperature is higher than the reference temperature. .

  According to a third aspect of the present invention, the cooling control means starts the operation of the Peltier element when the internal temperature becomes equal to or higher than the predetermined temperature, and operates the cold Peltier element when the internal temperature reaches the external temperature. It is intended to stop.

  The imaging device according to claim 4, a housing having thermal conductivity for holding the image sensor therein, an internal temperature sensor for measuring a temperature inside or inside the housing in which the image sensor is disposed, and an external device An outside temperature sensor for measuring the temperature, a humidity sensor for measuring the humidity of the outside air, a Peltier element having an endothermic surface attached to the outer surface of the housing, and a heat sink attached to the waste heat surface of the Peltier element When the dew point is obtained from the outside air temperature measured by the outside air temperature sensor and the outside air humidity measured by the humidity sensor, the internal temperature measured by the internal temperature sensor is compared with the dew point, and the internal temperature is higher than the dew point. And a cooling control means for driving and cooling the Peltier element.

  Further, in the photographing apparatus according to claim 5, a housing having thermal conductivity for holding the image sensor inside, an internal temperature sensor for measuring the temperature inside the housing in which the image sensor is arranged or the housing, The humidity sensor for measuring the humidity inside the housing, the Peltier element with the heat absorbing surface attached to the outer surface of the housing, the heat sink attached to the waste heat surface of the Peltier element, and the power supply were turned on Immediately after that, the dew point is obtained from the temperature measured by the internal temperature sensor and the humidity measured by the humidity sensor, the internal temperature measured by the internal temperature sensor is compared with the dew point, and the internal temperature is higher than the dew point. And a cooling control means for driving and cooling the Peltier element.

  In the photographing apparatus according to claim 6, the cooling control means starts the operation of the Peltier element when the internal temperature becomes equal to or higher than the predetermined temperature, and stops the operation of the Peltier element when the internal temperature reaches the dew point. It is a thing. According to a seventh aspect of the present invention, there is provided a photographing device including a fan for allowing air around the heat sink to flow during driving of the Peltier element. The imaging apparatus according to claim 8, wherein a circuit board on which a circuit constituting cooling control means is formed is housed in a housing, and an internal temperature sensor is arranged on the circuit board. In the apparatus, a circuit board on which a circuit constituting cooling control means is formed is housed in a housing, and an internal temperature sensor and a humidity sensor are arranged on the circuit board.

  The photographing apparatus according to claim 10 is provided with display means for displaying information related to cooling. In the photographing apparatus according to claim 11, the fact that cooling is being performed is displayed on the display means. In the photographing apparatus described in item 12, at least temperature information measured by the internal temperature sensor is displayed on the display means. According to a thirteenth aspect of the present invention, the display surface for displaying the information related to cooling of the display means is provided so as to be inclined obliquely upward and the display surface is provided in the fourteenth aspect. It is movable between a horizontally tilted position and a position inclined obliquely upward. Further, in the photographing apparatus according to the fifteenth aspect, the display means is a film-like display plate provided along the outer peripheral surface. According to a sixteenth aspect of the present invention, the display means is a light emitting diode that is lit during cooling.

  According to a seventeenth aspect of the present invention, there is provided a photographing lens that forms a subject image on a light receiving surface of an image sensor, a circuit that drives the image sensor and performs signal processing on an image signal from the image sensor, and a camera body. And a mount portion for mounting.

  According to the photographing apparatus of the present invention, the internal temperature, the outside air temperature, the humidity and the like in which the image sensor is arranged are measured by the sensor, and the cooling is performed only while the internal temperature is higher than the outside air temperature or the dew point. Therefore, the image sensor can be cooled without causing dew condensation on the image sensor or the housing housing the image sensor. Thereby, the noise accompanying the temperature rise of an image sensor can be suppressed.

  A first embodiment of the present invention will be described. As shown in FIG. 1, the digital camera 2 includes a main body unit 4 as a camera body provided with a release button 3 and the like, and a lens unit 7 having a photographing lens 5 and an image sensor 6 (see FIG. 2). . Various signals are exchanged between the main body unit 4 and the lens unit 7, and an image photographed by the lens unit 7 based on the operation of the main body unit 4 is displayed on the main body unit 4, or predetermined It is designed to record on recording media. The lens unit 7 is detachable from the main unit 4, and a plurality of types of lens units 7 having different focal lengths and performances of the image sensor 6 can be selected and attached to the main unit 4.

  The lens unit 7 is provided with a mount portion 9 having a bayonet claw 8 formed on the back surface thereof, and the main body unit 4 is provided with a mount portion 12 having a bayonet groove 11 formed on the front surface thereof. The lens unit 7 is attached to the main unit 4 by aligning and pushing the bayonet claw 8 into the bayonet groove 11 and rotating it to a fixed position. Note that the light receiving surface of the image sensor 6 is in a horizontally long posture when the fixed position is set in this way.

  When the lens unit 7 is set to the fixed position, the lock pin 13 biased forward engages with the pin hole formed in the mount portion 9, whereby the rotation of the lens unit 7 is locked. Further, when the lock release button 14 is pressed, the engagement between the lock pin 13 and the pin hole is released, and the lens unit 7 is allowed to rotate and can be detached from the camera body 4.

  The mount lid 16 provided in the center of the mount portion 9 is biased forward, and when the lens unit 7 is not attached, the opening into which the bayonet claw 8 enters as shown in FIG. When the lens unit 7 is mounted, the lens unit 7 is allowed to be mounted by being pressed by the lens unit 7 and moving backward.

  The bayonet claw 8 is provided with a terminal portion 17 composed of a plurality of contacts. The terminal portion 17 is connected to a terminal portion 18 (see FIG. 3) provided inside the mount portion 12 when the lens unit 7 is attached to the main body unit 4. Thereby, the circuit built in the main unit 4 and the circuit built in the lens unit 7 are electrically connected.

  On the front surface of the main unit 4 is provided a strobe light emitting unit 19 that irradiates a subject with strobe light at the time of photographing. On the top surface, in addition to the release button 3 that is pressed when photographing, photographing for taking a still image is performed. A mode switching dial 20 is provided for switching between a mode and a reproduction mode for reproducing and displaying a captured image. Further, an LCD (liquid crystal display) or the like for displaying a through image display or a photographed image is provided on the back surface of the main unit 4.

  As will be described later, the lens unit 7 is provided with an intake port 22 and an exhaust port 23 for inhaling and exhausting outside air for enhancing the heat dissipation effect of heat generated when the image sensor 6 or the like is cooled. .

  As shown in FIG. 2, the lens unit 7 is roughly composed of a lens barrel portion 25, a sensor barrel portion 26, a fan unit 7, and a mount portion 9. The lens barrel section 25 includes a photographic lens 5, a photographic lens 5, a lens barrel 28 incorporating a shutter device, a diaphragm device, a focus adjustment mechanism, and the like. The sensor barrel portion 26 includes an image sensor 6, a circuit board 31, an inner heat sink 32, a Peltier element 33, and an outer heat sink 34.

  The inner heat sink 32 is for releasing heat generated by various circuits opened in the image sensor 6 and the circuit board 31 to the outside, and is made of a material having high thermal conductivity, such as aluminum or copper. The housing includes a sensor holder 37 and a substrate holder 38 formed of silver or the like and holds the image sensor 6 therein. The sensor holder 37 has a cylindrical shape having substantially the same diameter as that of the lens barrel 25, and is provided with a sensor holding plate 37a so as to partition the hollow interior in the front-rear direction. The image sensor 6 is attached to the center of the sensor holding plate 37a, that is, an opening provided at a position through which the optical axis of the photographing lens 6 passes.

The image sensor 6 is arranged with the light receiving surface 6a facing forward, and outputs an image signal obtained by photoelectrically converting a subject image formed by the photographing lens 6. As the image sensor 6, for example, a CCD image sensor is used. However, the image sensor 6 is not limited to this, and a MOS type image sensor can be used.
The image sensor 6 is configured such that heat from the image sensor 6 is easily transmitted to the sensor holder 37 by, for example, bringing the package into close contact with the sensor holder 37.

  The circuit board 31 communicates with a circuit that drives the image sensor 6 to perform various processing on the image signal, a drive circuit for driving a shutter device, a diaphragm device, a focus adjustment mechanism, and the like, and the main unit 4. A circuit or the like for performing is formed. The substrate holder 38 has a disk shape having substantially the same diameter as the outer diameter of the sensor holder 37, and holds the circuit board 31 on the inner surface of the sensor holder 37. Therefore, the circuit board 31 is arranged in a sealed sensor holder 37 in the same manner as the image sensor 6.

  The inside of the sensor holder 37 in which the image sensor 6 is arranged as described above is sealed by attaching the lens barrel portion 25 to the front end of the sensor holder 37 and the substrate holder 38 to the rear end. The substrate holder 38 is attached in close contact with the rear end of the sensor holder 37 so that heat from the sensor holder 37 is easily transmitted.

  As is well known, the Peltier element 33 can cool the endothermic surface side by passing a direct current and moving the heat of one surface, that is, the endothermic surface, to the other waste heat surface. It is provided to cool the sensor 6. The Peltier element 33 has its heat absorption surface in close contact with the back side of the substrate holder 38, and cools the image sensor 6 via the inner heat sink 32.

  The outer heat sink 34 is provided to efficiently dissipate heat from the waste heat surface of the Peltier element 30 to the outside, and is formed of a material having high thermal conductivity like the inner heat sink 32. The outer heat sink 34 is formed in a substantially cylindrical shape having an inner diameter larger than the outer diameter of the inner heat sink 32, and a plurality of heat radiation fins 34a elongated along the optical axis 6a are provided on the inner peripheral surface thereof. The space between the heat radiating fins 34a serves as a passage for the outside air sucked in, and the front end portion of the passage serves as the intake port 22 described above. Further, a rear end plate 34b is provided at the rear end of the outer heat sink 34. The rear end plate 34b guides the outside air from the intake port 22 to the fan unit 27 in a portion between the radiation fins 34a. Vent hole 34c is provided.

  The aforementioned inner heat sink 32 is disposed inside the outer heat sink 34. The waste heat surface of the Peltier element 30 is brought into close contact with the rear end plate 34b so that the Peltier element 33 is sandwiched between the substrate holder 38 and the rear end plate 34b, and the heat of the waste heat surface is easily transferred to the outer heat sink 34. It is. In addition, it is preferable that an appropriate interval is provided between the inner heat sink 32 and each radiating fin 34 a so that the heat of the outer heat sink 34 is not transmitted to the inner heat sink 32.

  A fan unit 27 is provided at the rear part of the outer heat sink 34, and a mount part 9 is provided at the rear part of the fan unit 27. The fan unit 27 has the same outer diameter as that of the outer heat sink 34, and has a fan 27b built in an outer cylinder 27a having an exhaust port 23 on the outer peripheral surface. As the fan 27 rotates, outside air is sucked from the air inlet 22 and flows between the heat radiating fins 34 a, flows into the fan unit 27 through the air holes 34, and is discharged from the air outlet 23. In this manner, the fan unit 27 promotes heat dissipation of the outer heat sink 34 by actively flowing outside air between the heat dissipating fins 34 a, that is, by causing air around the outer heat sink 34 to flow, and the Peltier element 33. In addition to enhancing the cooling effect, excessive temperature rise of the waste heat surface is prevented. In this example, there is also an effect of promoting heat dissipation of the inner heat sink 32 by flowing outside air between the heat radiating fins 34 a and simultaneously flowing outside air to the outside of the inner heat sink 32.

  In this example, the heat sink is constituted by the outer heat sink 34 and the fan 27b. However, as long as the heat dissipating means releases heat from the Peltier element 33 to the outside, another structure is adopted. be able to.

  The outside air temperature sensor 41 measures the outside air temperature sucked from the suction port 22. The outside air temperature sensor 41 is provided on the heat radiating fin 34a in the vicinity of the suction port 22. For example, by installing a heat insulating material between the heat radiating fin 34a, the heat of the heat radiating fin 34a is provided. The temperature of the outside air to be inhaled is measured without being affected by the above. The attachment position of the outside air temperature sensor 41 is not limited to the above, and may be anywhere as long as the outside air temperature can be measured.

  The internal temperature sensor 42 measures the temperature on the side cooled by the Peltier element 33 (hereinafter referred to as internal temperature). In this example, the temperature sensor 42 is attached to the inner surface of the substrate holder 38 and measures the temperature of the inner heat sink 32, in this case, the portion of the substrate holder 38. The temperature of the sensor holder 37 and the atmosphere inside the sensor holder 38 are measured. The temperature may be measured, and it is preferable to measure the temperature of the portion where the temperature is most lowered by the Peltier element as in this example from the viewpoint of preventing condensation. Various types of temperature sensors 41 and 42 can be used. In this example, a thermistor is used.

  As shown in FIG. 3, the lens unit 7 includes a photographing unit 46, a lens-side communication unit 47, a cooling unit 48, and a lens-side control unit 49 that control these in an integrated manner. These circuit components are mounted on the circuit board 31 described above. The imaging unit 46 includes an image sensor 6, a circuit that drives the image sensor 6, a correction circuit that performs correction processing on an image signal from the image sensor 6, and an A / D converter that converts the image signal into digital data by converting the image signal. Etc. The lens side communication unit 47 is connected to a circuit on the main unit 4 side through the terminal units 17 and 18 to exchange various data.

  As shown in FIG. 4, the cooling unit 48 includes a fan 27 b, a Peltier element 33, an outside air temperature sensor 41, an internal temperature sensor 42, and a cooling control circuit 50, and controls cooling by the Peltier element 33. An external temperature measured by the outside air temperature sensor 41 and an internal temperature measured by the internal temperature sensor 42 are input to the cooling control circuit 50. When the power is turned on, the cooling control circuit 50 refers to the internal temperature, and starts cooling the Peltier element 30 and the fan 27b by energizing the internal temperature when the internal temperature rises to a predetermined temperature Ts. . During cooling, in order to prevent condensation, the outside air temperature and the inside temperature are compared, and when the inside temperature falls to the outside air temperature, the Peltier device 30 and the fan are deenergized to stop the cooling. In this way, cooling starts when the internal temperature exceeds the specified temperature, continues cooling only while the internal temperature is higher than the outside temperature, and stops cooling when the internal temperature reaches the outside temperature. To do. The predetermined temperature Ts can be appropriately set in consideration of the characteristics of the image sensor, the measurement position of the internal temperature sensor, the structure of the sensor holder, and the like. In this example, when a CCD type or a CMOS type is used as the image sensor 6, 45C ° is set as the predetermined temperature Ts.

  As shown in FIG. 3, the main body unit 4 includes a main body side communication unit 52, a data processing unit 53, a display unit 54, a recording unit 55, a main body side control unit 56, and the like connected by a bus 51. The operation unit 57 includes the release button 3, the mode switch 20 and the like. The main body side control unit 56 controls each part of the main body unit 4 in response to the operation of the operation unit 57, and communicates with the lens unit 7 to execute photographing or the like. The main body side communication unit 52 is connected to the lens side communication unit 47 via the terminal units 18 and 17, and exchanges various data.

  The data processing unit 53 compresses or decompresses image data. The display unit 54 includes an LCD provided on the back surface of the main unit 4 and a circuit for driving the LCD based on image data, and displays a through image and a captured image on the LCD. The recording unit 55 is for recording image data obtained by photographing with the lens unit 7, and includes a recording medium, a media controller for recording and reading data on the recording medium, and the like.

  The power controller 58 transforms the output voltage of the battery 58b to a predetermined voltage in response to turning on of the power switch 58a, and supplies it to each part of the main unit 4. The power controller 58 supplies power to the power unit 59 of the lens unit 7 via the terminal units 18 and 17, and the power unit 59 supplies power to each part of the lens unit 7.

  Next, the operation of the above configuration will be described. When the photographing mode is selected by turning on the power switch 58a, the subject light that has passed through the photographing lens 5 is imaged on the light receiving surface of the image sensor 6, and the imaged subject image is photoelectrically converted and output as an image signal. After this image signal is converted into image data by the photographing unit 46, it is sent to the display unit 54 via the lens side communication unit 47 and the main body side communication unit 52, and a through image is displayed on the LCD. Since the photoelectric conversion by the image sensor 6 is repeatedly performed at a predetermined cycle, the through image is displayed as a moving image on the LCD.

  When the release button 3 is pressed, a signal corresponding to the operation is sent to the lens unit 7, and a still image is taken by the image sensor 6. Image data obtained by this photographing is sent to the data processing unit 53 of the main unit 4 and compressed, and then sent to the recording unit 55 where it is recorded on the recording medium. In this way, a still image is taken.

  By the way, when the photographing mode is selected, the image sensor 6 is always in operation, and each circuit provided on the circuit board 31 is also in operation, so these generate heat and the temperature rises. The temperature of the inner heat sink 32 also rises.

  On the other hand, after the power switch 58a is turned on, the internal temperature measured by the internal temperature sensor 42 is monitored by the cooling control circuit 50, and when the internal temperature reaches a predetermined temperature Ts as shown in FIG. Energization to the Peltier element 33 and the fan 27b is started.

  When energization to the Peltier element 33 is started, the inner heat sink 32 is thereby cooled, and each circuit on the image sensor 6 and the circuit board 31 is cooled accordingly. Further, when the fan 27b starts to rotate, the outside air from the intake port 22 passes between the radiation fins 34a of the outer heat sink 34 heated by the Peltier element 33, so that the waste heat of the Peltier element 33 is radiated by the radiation fins. The heat is efficiently radiated through 34a. The outside air thus heated flows into the fan unit 27 from the vent hole 34 c and is exhausted from each exhaust port 23.

  When the cooling is started as described above, the cooling control circuit 50 repeatedly obtains the outside temperature measured by the outside temperature sensor 41 and the inside temperature measured by the inside temperature sensor at a predetermined cycle. Compared to In this comparison, when the internal temperature is higher than the outside air temperature, the cooling is continued, but when the internal temperature becomes equal to the outside air temperature, the energization to the Peltier element 33 and the fan 27b is stopped and the cooling is stopped.

  After the cooling is stopped, the internal temperature is monitored, and when the internal temperature reaches a predetermined temperature Ts, energization to the Peltier element 33 and the fan 27b is started again to perform cooling. Thereafter, control for cooling is similarly performed. As a result, the image sensor 6 and the inner heat sink 32 are not cooled below the outside air temperature, so that no condensation occurs.

  Next, a second embodiment in which control is performed using only the internal temperature sensor will be described. Since the configuration of the lens unit in the second embodiment is the same as that of the first embodiment except that no external temperature sensor is provided, the illustration of the configuration is omitted. In this example, the cooling control circuit 50 assumes that the temperature measured by the internal temperature sensor 42 is equal to the temperature of the outside air when the power switch 58a is turned on as shown in FIG. When the internal temperature measured by the internal temperature sensor 42 has dropped to the reference temperature after the start of cooling, the cooling is controlled to stop. According to this, since only one temperature sensor needs to be used, the number of parts can be reduced.

  FIG. 7 shows a third embodiment in which a humidity sensor is provided in addition to an outside air temperature sensor and an internal temperature sensor. In addition, since it is the same as that of 1st Embodiment except being demonstrated below, the same code | symbol is attached | subjected to the same structural member and the description is abbreviate | omitted. A humidity sensor 61 is provided in the vicinity of the air inlet 22 of the radiating fin 34a to measure the humidity of the outside air to be taken in. The humidity sensor 61 can measure the humidity of the outside air without being affected by the heat from the heat radiating fins 34a, for example, by arranging a heat insulating material between the heat radiating fins 34a in the same manner as the outside air temperature sensor 41. As shown in FIG. 8, the cooling control circuit 50 calculates the dew point of the outside air based on the external temperature measured by the outside air temperature sensor 41 and the humidity of the outside air measured by the humidity sensor 61, and the internal temperature sensor 42. Control is performed to stop cooling when the internal temperature measured in step 1 drops to the dew point. According to this, the internal temperature can be further lowered within a range where condensation does not occur, and the noise accompanying the temperature rise of the image sensor can be further reduced.

  As in the second embodiment, the outside air temperature sensor is omitted, the internal temperature sensor and the humidity sensor are provided inside the inner heat sink, and the internal temperature sensor and the humidity sensor are measured when the power switch 58a is turned on. The dew point may be obtained using the measured temperature and humidity, and cooling may be controlled by comparing the dew point with the internal temperature.

  In each of the above embodiments, the internal temperature sensor is arranged on the substrate holder that is a part of the inner heat sink. However, for example, as shown in FIG. 9, the internal temperature sensor 42 may be provided on the circuit board 31. In this way, the internal temperature sensor 42 and the cooling control circuit 50 on the circuit board 31 can be connected using the wiring pattern of the circuit board 31, so that a harness can be eliminated and the number of components can be reduced. .

  FIG. 10 shows a fourth embodiment provided with an indicator indicating that the cooling operation is being performed. In addition, since it is the same as that of 1st Embodiment except being demonstrated below, the same code | symbol is attached | subjected to the same structural member and the description is abbreviate | omitted. Moreover, although the example which provided the indicator in the structure of 1st Embodiment is demonstrated, it cannot be overemphasized that it can comprise similarly about the other example demonstrated above.

  An LED (light emitting diode) 64 is provided on the circuit board 31, and the LED 64 is lit during cooling, that is, while the Peltier element 33 and the fan 27b are operating. The light guide 65 is provided through the outer heat sink 34 and the sensor holder 32 so that one end thereof faces the LED 64 and the other end is exposed to the outer peripheral surface of the outer heat sink 34. Thereby, the lighting and extinguishing of the LED 64 can be confirmed from the outside via the light guide 65, and the user can know whether or not the cooling is in progress. Alternatively, the LED 64 may be provided outside the lens unit 7 without providing the light guide 65 so that the lighting and extinguishing of the LED 64 can be directly recognized. In this example, the LED 64 is used as an indicator, but it may be displayed that cooling is being performed using another light source or display means.

  FIG. 11 shows a fifth embodiment in which temperature display is performed. In this example, a display portion 67 is provided on the outer peripheral surface of the sensor barrel portion 26 of the lens unit 7. The display unit 67 includes an LCD 67a and the like, and displays various information related to cooling on the LCD 67a under the control of the cooling control circuit 50. As shown in an example of the temperature display in FIG. 12, in this example, the outside air temperature measured by the outside air temperature sensor 41 and the inside temperature measured by the inside temperature sensor 42 are displayed as information related to cooling. In addition, as information regarding cooling, various things, such as the dew point of external air, the information whether it is during cooling, a temperature change, can be employ | adopted. By displaying the cooling status in this way, the user can check the status, and the user can predict battery consumption to some extent.

  The display unit for displaying various information related to cooling is preferably highly visible to the operator. Like the display unit 68 shown in FIG. 13, the LCD 68a is horizontally tilted as shown in FIG. As shown by the dotted line, the LCD 68a may be tilted at an appropriate angle from the storage position so that the LCD 68a can be moved between the tilted position in the rearward and upward direction so that the user can easily confirm from behind. Further, like the display unit 69 shown in FIG. 14, the LCD 69 a may be inclined at an appropriate angle so as to be inclined obliquely upward.

  Furthermore, as shown in FIG. 15, if a film-like display board 71 is provided along the outer peripheral surface of the outer heat sink 34, for example, and information related to cooling is displayed, the appearance design may be affected. Absent. As the film-like display board 71, for example, a flexible display device using an organic EL element can be used.

  In 6th Embodiment shown in FIG. 16, the cooling cancellation | release button 73 which stops cooling operation is provided with the display part 72 which displays the information regarding cooling. By pressing the cooling release button 73 during the cooling operation, the cooling by the Peltier element 33 and the fan 27b is forcibly stopped. Thereby, when the battery is depleted, the cooling release button 73 is pressed to stop the cooling, so that the number of times of photographing can be increased or the photographing time can be lengthened. In addition, as information regarding cooling, the remaining amount of the battery, the remaining time that can be photographed based on that, and the number of times that photography can be performed may be displayed.

  In each of the embodiments described above, in the digital camera in which the lens unit is detachably attached to the main unit, the case where the lens unit is used as a photographing device and an image sensor or the like built in the lens unit is cooled has been described. The present invention can also be used for conventional digital cameras in which the camera is integrated, and photographing apparatuses such as interchangeable lens digital cameras provided with an image sensor on the main unit side.

It is a perspective view which shows the external appearance of the digital camera which implemented this invention. It is a fragmentary sectional view which shows the structure of a lens unit. It is a block diagram which shows the electric constitution of a digital camera. It is a block diagram which shows the structure of a cooling unit. It is a flowchart which shows the process sequence of control of cooling. It is a flowchart which shows the process sequence of the control of cooling in the example which provided only the internal temperature sensor. It is a fragmentary sectional view which shows the structure of the lens unit of the example which provided the humidity sensor. It is a flowchart which shows the process sequence of the control of cooling in the example which provided the humidity sensor. It is a fragmentary sectional view which shows the structure of the lens unit of the example which provided the internal temperature sensor on the circuit board. It is a fragmentary sectional view which shows the structure of the lens unit of the example which provided LED which turns on during cooling. It is a perspective view which shows the external appearance of the lens unit of the example which provided the display part which performs temperature display. It is explanatory drawing which shows the example of a display of a display part. It is a perspective view which shows the external appearance of an example lens unit by making the display part which performs temperature display into a movable type. It is a perspective view which shows the external appearance of the lens unit of the example which inclined the display surface of the display part which performs temperature display. It is a perspective view which shows the external appearance of the lens unit of the example which provided the display board along the outer peripheral surface of an outer side heat sink. It is a perspective view which shows the external appearance of the lens unit of the example which provided the cooling cancellation | release button.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Digital camera 4 Camera main body 5 Shooting lens 6 Image sensor 7 Lens unit 9 Mount part 27b Fan 32, 34, Heat sink 33 Peltier element 41 Outside temperature sensor 42 Internal temperature sensor 50 Cooling control circuit 61 Humidity sensor

Claims (17)

In an imaging device including an image sensor that photoelectrically converts a subject image to generate an image signal,
A housing having thermal conductivity for holding the image sensor inside; an internal temperature sensor for measuring the temperature inside or inside the housing in which the image sensor is arranged; and an outside air temperature sensor for measuring an external temperature; , Measured by the Peltier element having the heat absorption surface attached to the outer surface of the housing, the heat sink attached to the waste heat surface of the Peltier element, the internal temperature measured by the internal temperature sensor, and the outside air temperature sensor And a cooling control means for driving and cooling the Peltier element only when the internal temperature is higher than the outside air temperature. In an imaging device including an image sensor that photoelectrically converts a subject image to generate an image signal,
A housing having thermal conductivity for holding the image sensor inside, an internal temperature sensor for measuring the temperature inside or inside the housing in which the image sensor is disposed, and a heat absorbing surface on an outer surface of the housing Peltier element to which is attached, a heat sink attached to the waste heat surface of the Peltier element, and the temperature measured by the internal temperature sensor immediately after the power is turned on as a reference temperature, the reference temperature and the internal temperature An imaging apparatus comprising: cooling control means for comparing the internal temperature measured by a sensor and driving and cooling the Peltier element only when the internal temperature is higher than a reference temperature. The cooling control unit starts the operation of the Peltier element when the internal temperature becomes equal to or higher than a predetermined temperature, and stops the operation of the Peltier element when the internal temperature reaches the external temperature. Or the imaging device of 2. In an imaging device including an image sensor that photoelectrically converts a subject image to generate an image signal,
A housing having thermal conductivity for holding the image sensor inside; an internal temperature sensor for measuring the temperature inside or inside the housing in which the image sensor is arranged; and an outside air temperature sensor for measuring an external temperature; Measured by a humidity sensor for measuring the humidity of the outside air, a Peltier element having a heat absorbing surface attached to the outer surface of the housing, a heat sink attached to the waste heat surface of the Peltier element, and an outside temperature sensor The dew point is obtained from the outside air temperature and the humidity of the outside air measured by the humidity sensor, the internal temperature measured by the internal temperature sensor is compared with the dew point, and the Peltier element is driven only when the internal temperature is higher than the dew point. And a cooling control means for cooling. In an imaging device including an image sensor that photoelectrically converts a subject image to generate an image signal,
A housing having heat conductivity for holding the image sensor therein, an internal temperature sensor for measuring the temperature inside or inside the housing in which the image sensor is arranged, and a humidity sensor for measuring the humidity inside the housing And a Peltier element having an endothermic surface attached to the outer surface of the housing, a heat sink attached to the waste heat surface of the Peltier element, and measured by the internal temperature sensor immediately after the power was turned on. The dew point is obtained from the temperature and the humidity measured by the humidity sensor, the internal temperature measured by the internal temperature sensor is compared with the dew point, and the Peltier element is driven and cooled only when the internal temperature is higher than the dew point. An imaging apparatus comprising a cooling control means. The cooling control means starts the operation of the Peltier element when the internal temperature becomes equal to or higher than a predetermined temperature, and stops the operation of the Peltier element when the internal temperature reaches a dew point. 4. The photographing apparatus according to 4 or 5.   The photographing apparatus according to claim 1, further comprising a fan that causes the air around the heat sink to flow during driving of the Peltier element.   8. A circuit board on which a circuit constituting the cooling control means is formed in the housing, and the internal temperature sensor is arranged on the circuit board. The imaging device according to item.   6. The photographing according to claim 5, wherein a circuit board on which a circuit constituting the cooling control means is formed is housed in the housing, and the internal temperature sensor and the humidity sensor are arranged on the circuit board. apparatus.   10. The photographing apparatus according to claim 1, further comprising display means for displaying information related to cooling.   The imaging apparatus according to claim 10, wherein the display unit displays that cooling is in progress.   The photographing apparatus according to claim 10, wherein the display unit displays at least temperature information measured by an internal temperature sensor.   The photographing apparatus according to any one of claims 10 to 12, wherein the display means is provided so that a display surface for displaying information on cooling is inclined obliquely upward.   14. The display unit according to claim 13, wherein the display means is movable between a position where a display surface for displaying information related to cooling is tilted horizontally and a position inclined obliquely upward. Shooting device.   14. The photographing apparatus according to claim 13, wherein the display means is a film-shaped display plate provided along the outer peripheral surface.   12. The photographing apparatus according to claim 11, wherein the display means is a light emitting diode that is lit during cooling.   A photographic lens that forms a subject image on a light receiving surface of the image sensor; a circuit that drives the image sensor to perform signal processing on an image signal from the image sensor; and a mount unit that is attached to the camera body. The imaging apparatus according to claim 1, further comprising: an imaging apparatus according to claim 1.

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