JP2003143449A - Solid-state image pickup device and method for operating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state image pickup device capable of reliably preventing occurrence of moisture condensation when a solid-state image pickup element is operated at a lower temperatures than the room temperatures, and to provide a method for operating the solid-state image pickup device. SOLUTION: A solid-state image pickup device 1 contains a solid-state image pickup elements 21, 22, 23 for photoelectrically transferring the lights; Peltier elements 31, 32, 33 for cooling each of the solid-state image pickup elements; a casing 2 for accommodating at least each of the solid-state image pickup elements and each of the Peltier elements; an electric decomposition cell 8f for advancing an electrochemical oxidative decomposition reaction of vapor within the casing; and an image processing part 7 equipped with a controller. The controller controls the output of each of the Peltier elements; adjusts the operating temperatures of each of the solid-state image pickup elements to a predetermined temperature of an external environmental temperature or below; and independently controls each timing to start and stop the solid-state image pickup elements, the Peltier elements, and the electric decomposition cell so as to satisfy conditions that a vapor pressure within the casing becomes a predetermined value of a saturated vapor pressure or below at operating temperatures.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state imaging device using a solid-state imaging device and a method for operating the solid-state imaging device.

[0002]

2. Description of the Related Art In order to obtain a clear image in a solid-state image pickup device using a solid-state image pickup device such as a CCD, it is important to prevent an increase in dark current due to a temperature rise of the solid-state image pickup device during operation. Therefore, the solid-state imaging device has
A cooling mechanism having a Peltier element, a radiator, or the like for cooling the operating solid-state image sensor to prevent its temperature rise is provided.

However, when the cooling mechanism as described above is provided, there is a problem that dew condensation occurs on the image pickup element surface of the solid-state image pickup device under a high temperature and high humidity environment. As a method for solving this problem, it is conceivable to increase the airtightness in the housing in which the solid-state image pickup device of the solid-state image pickup device is mounted.
There is a problem that it is necessary to increase the part processing accuracy, the part cost increases, and maintainability and long-term repeated use cannot be endured.

Therefore, for example, Japanese Patent Laid-Open No. 6-13322.
In Japanese Patent Publication No. 8, a Peltier element for dehumidification different from the Peltier element for cooling the image pickup device is arranged in the vicinity of the image pickup surface, and the temperature of the Peltier element for dehumidification is set to a temperature lower than that of the Peltier element for cooling the image pickup device. An image pickup apparatus control method has been proposed in which the Peltier element for dehumidification is controlled to condense dew to dehumidify.

Further, in Japanese Patent Laid-Open No. 10-56587, in order to prevent dew condensation on the image pickup surface of a television camera including an image pickup device and a cooling device for cooling the image pickup device, the power of the television camera is turned on. There has been proposed a method for controlling a cooling device for a television camera, which is characterized in that a Peltier element of the cooling device is operated after a predetermined time has elapsed.

[0006]

However, the solid-state image pickup device control method described in Japanese Patent Laid-Open No. 6-133228 described above requires a Peltier element for dehumidification in addition to the Peltier element for cooling the image pickup device, and thus dehumidification is performed. However, there is a problem that the cooling efficiency is reduced due to the Peltier device for the vehicle. Further, there is a drawback that a space for a Peltier element for dehumidification is required and the apparatus configuration is complicated and the cost is high. Further, when the humidity of the external environment is high, there is a problem that dew condensation occurs due to the Peltier device for dehumidification.

Further, the control method for a cooling device for a television camera disclosed in Japanese Patent Laid-Open No. 10-56587 discloses a case where a solid-state image pickup element is cooled to a temperature lower than an external environmental temperature (for example, room temperature) to operate. There is a problem of dew condensation, which is still insufficient for obtaining a good picked-up image.

The present invention has been made in view of the above problems of the prior art, and it is possible to reliably prevent dew condensation even when the solid-state image pickup device is operated at a temperature lower than room temperature. An object is to provide a solid-state imaging device and a method for operating the solid-state imaging device.

[0009]

The present invention is directed to a solid-state image sensor for photoelectrically converting light, a cooling element for cooling the solid-state image sensor, which is arranged adjacent to the solid-state image sensor, and the solid-state image sensor. A case that houses at least the element, an electrolysis cell that promotes an electrochemical oxidative decomposition reaction of water vapor in the case, and an output of the cooling element to control the operating temperature of the solid-state image sensor to a predetermined temperature equal to or lower than the external environmental temperature. Adjust to temperature,
Further, control for independently controlling the start and stop timings of the solid-state imaging device, the cooling element, and the electrolysis cell so that the water vapor pressure in the case satisfies a predetermined value that is equal to or lower than the saturated water vapor pressure at the operating temperature. A solid-state imaging device, comprising: a device.

When the cooling element is used to operate the solid-state image sensor at a predetermined temperature below the external environmental temperature,
Condensation in the solid-state imaging device is particularly likely to occur when the solid-state imaging device is started and stopped, but the solid-state imaging device, the cooling element, and the electrolysis cell are staggered at different start and stop timings in the case. By adjusting the partial pressure of water vapor so as to satisfy the above condition, it is possible to prevent the occurrence of dew condensation and obtain a good captured image.

Here, the "external environment temperature" refers to the temperature of the external environment of the case that houses at least the solid-state image sensor and the cooling element.

In the present invention, from the viewpoint of sufficiently suppressing the increase of dark current in the solid-state image pickup device, the operating temperature of the solid-state image pickup device is preferably set to a predetermined value lower than the external environment temperature. It is more preferable to adjust the temperature to be 20 ° C. or more lower than the temperature. More specifically, the operating temperature of the solid-state imaging device is preferably set to 0 ° C. or lower.

Further, in the present invention, from the viewpoint of sufficiently preventing the occurrence of dew condensation, it is preferable that the water vapor pressure in the case is set to a predetermined value lower than the saturated water vapor pressure at the above-mentioned operating temperature. It is more preferably adjusted to 10% or less when converted into relative humidity (expressed as a percentage) at temperature, and further preferably adjusted to 5% or less.

In the above case, at the time of activation, the control device activates the solid-state image pickup element and the electrolysis cell first before the cooling element, and then activates the cooling element after a predetermined time when the above conditions are satisfied. Is preferred. As described above, by delaying the activation timing of the cooling element with respect to the activation timing of the solid-state imaging device and the electrolysis cell, it is possible to more reliably prevent the occurrence of dew condensation. In this case, the solid-state imaging device and the electrolysis cell may be activated at the same timing, or either one may be activated first.

Further, in the above-mentioned case, at the time of stop, the control device stops the solid-state image pickup element and the cooling element before the electrolysis cell, and then stops the electrolysis cell after a predetermined time when the above conditions are satisfied. It is preferable.

As described above, by delaying the stop timing of the electrolysis cell with respect to the stop timing of the solid-state image pickup element and the cooling element, it is possible to more reliably prevent the occurrence of dew condensation, and the solid-state image pickup device is again provided. It can be started promptly when it is started. In this case, the solid-state image sensor and the cooling element may be stopped at the same time, or either one may be stopped first, but it is preferable to stop the cooling element before the solid-state image sensor.

Further, in the solid-state image pickup device of the present invention,
A humidity sensor that detects the water vapor pressure in the case is further provided, and the control device controls the start and stop timings of the solid-state imaging device, the cooling element, and the electrolysis cell based on the water vapor pressure detected by the humidity sensor. May be controlled independently. By using the humidity sensor, it is possible to more reliably prevent the occurrence of dew condensation.

The optimum value of the time from the activation of the solid-state imaging device and the electrolysis cell to the activation of the cooling element and the optimum time from the stop of the solid-state imaging device and the cooling element to the termination of the electrolysis cell are previously determined by experimental data and the like. Keep in mind that a timer or the like is connected instead of the humidity sensor to automatically start the cooling element in response to the activation of the solid-state imaging element and the electrolysis cell, and stop the electrolysis cell for the solid-state imaging element and the cooling element. It may be set.

In the solid-state image pickup device of the present invention,
A temperature sensor for detecting the temperature of the solid-state image sensor is further provided, and the control device starts and stops the solid-state image sensor, the cooling element, and the electrolysis cell based on the temperature of the solid-state image sensor detected by the temperature sensor. May be controlled independently of each other, and the output of the cooling element after activation may be controlled.

As a result, it is possible to reduce fluctuations in the temperature of the solid-state image pickup device during operation. In addition, when stopping the solid-state imaging device, first stop the solid-state imaging device and the cooling element, and then when stopping the electrolysis cell, stop the solid-state imaging device and the cooling element, and then use the temperature sensor to perform the solid-state imaging. If the temperature of the device is monitored and the electrolysis cell is stopped after the temperature of the solid-state imaging device has risen sufficiently,
Condensation can be prevented more effectively.

Further, in the solid-state image pickup device of the present invention,
The electrolysis cell applies an anode that is a gas diffusion electrode, a cathode that is a gas diffusion electrode, a polymer electrolyte membrane arranged between the anode and the cathode, and a predetermined voltage between the anode and the cathode. It may be characterized by having a voltage application part.

As described above, an electrolysis cell having a structure in which a voltage applying section serving as an external power source is connected to a gas diffusion electrode of a so-called polymer electrolyte fuel cell (PEFC) is easy to reduce in size and weight, and thus solid-state imaging is possible. The device can be made compact. Further, the electrolysis cell having this configuration has high energy efficiency and extremely rapidly oxidizes and decomposes water vapor even at a very low temperature (eg, −20 ° C.) to obtain a desired humidity (eg, a relative humidity at an operating temperature of 5%). %
The following) can be easily dehumidified.

In this case, from the viewpoint of efficiently oxidizing and decomposing the water vapor in the case, the electrolysis cell provided in the case is such that the surface of the anode which is not in contact with the polymer electrolyte membrane faces the inside of the case. It is preferable that the cathode is arranged so that the surface of the cathode that is not in contact with the polymer electrolyte membrane is exposed to the outside of the case.

In the solid-state image pickup device of the present invention,
The cooling element may be a Peltier element. By using the Peltier device as the cooling device, it is possible to easily and efficiently cool the solid-state imaging device to a predetermined temperature equal to or lower than the external environment temperature. Further, since the Peltier device can be constructed in a lightweight and compact form and requires a small installation space, the solid-state imaging device can be constructed in a lightweight and compact form.

The present invention also provides a method for operating a solid-state image pickup device having a solid-state image pickup device for photoelectrically converting light, a cooling device for cooling the solid-state image pickup device, and a case for accommodating at least the solid-state image pickup device and the cooling device. That is, the output of the cooling element is adjusted to adjust the operating temperature of the solid-state imaging element to a predetermined temperature equal to or lower than the external environmental temperature, and an electrolysis cell is provided to electrochemically oxidize and decompose the water vapor in the case. By doing so, it is possible to independently adjust the start and stop timings of the solid-state imaging element, the cooling element, and the electrolysis cell so that the water vapor pressure in the case satisfies a predetermined value equal to or lower than the saturated water vapor pressure at the operating temperature. A method of operating a characteristic solid-state imaging device is provided.

In the above case, it is preferable that the solid-state image pickup device and the electrolysis cell are activated before the cooling device at the time of activation, and then the cooling device is activated after a lapse of a predetermined time when the above conditions are satisfied.

Further, in the above case, it is preferable to stop the solid-state image sensor and the cooling element before the electrolysis cell at the time of stop, and then stop the electrolysis cell after a predetermined time when the conditions are satisfied.

Further, in the operating method of the present invention, a humidity sensor for detecting the water vapor pressure in the case is provided, and based on the obtained water vapor pressure, the start and stop timings of the solid-state image pickup element, the cooling element and the electrolysis cell. May be adjusted independently.

Further, in the operating method of the present invention, a temperature sensor for detecting the temperature of the solid-state image pickup element is provided, and the solid-state image pickup element, the cooling element and the electrolysis cell are activated based on the obtained temperature of the solid-state image pickup element. The output timing of the cooling element after starting may be adjusted while adjusting the stop timing independently.

Further, in the operating method of the present invention, the electrolysis cell comprises an anode which is a gas diffusion electrode, a cathode which is a gas diffusion electrode, and a polymer electrolyte membrane which is arranged between the anode and the cathode. It may be characterized in that it has a voltage application unit for applying a predetermined voltage between the anode and the cathode.

Further, the operating method of the present invention may be characterized in that the cooling element is a Peltier element.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings will be denoted by the same reference numerals.

FIG. 1 is a perspective view showing a preferred embodiment of the solid-state image pickup device of the present invention. FIG. 2 is a front view of the solid-state imaging device shown in FIG. FIG. 3 is a rear view of the solid-state imaging device shown in FIG. FIG. 4 is a sectional view showing a schematic basic configuration of the solid-state imaging device taken along line II-II of FIG.

The solid-state image pickup device 1 of this embodiment is shown in FIGS.
As shown in FIG. 7, mainly, the color separation prism 10 and the solid-state image pickup elements 21, 22, 23 arranged on the light emission surfaces F11, F12, F13 of the color separation prism 10, respectively.
And the back surfaces F21, F22, F2 of these solid-state imaging devices
Peltier elements 31, 32, 3 respectively arranged on 3
3, cooling blocks 41, 42, 43 respectively arranged on the back surfaces of these Peltier elements, and heat pipes 51, 52, 53, 5 connected to these cooling blocks.
4, 55, 56, an image processing unit 7 for processing electric signals sent from each solid-state image pickup device, and a case 2 for accommodating each of the above-mentioned image pickup parts.

As shown in FIGS. 1 to 3, a case 2 having a substantially rectangular parallelepiped shape has a case body 3 having a U-shaped cross section.
The case cover 4 has a U-shaped cross section and is detachably attached to the case body.

The case 3 main body has a front panel 3a having an opening H2 formed therein, a rear panel 3b arranged so as to face the front panel 3a, and the above-described components for image pickup placed on the upper surface. And a bottom panel 3 in which a front panel 3a and a rear panel 3b are erected on opposite edges of the upper surface.
and c.

On the other hand, the case cover 4 has a front panel 3a and a rear panel 3b when the case 2 having a substantially rectangular parallelepiped shape is formed.
Two side panels forming a side surface between the top panel and the bottom panel are integrated. When the solid-state imaging device 1 is assembled, the case cover 4 includes cooling blocks 41, 42, 43 and heat pipes 51, 52, 53, 54 for supporting the cooling blocks 41, 42, 43.
55 and 56 are integrally connected beforehand. This allows
The work for mounting the color separation prism 10 in which the respective solid-state image pickup devices 21, 22, and 23 are mounted in the case 2 becomes easy.

The case cover 4 functions as a heat radiating plate, and a groove formed substantially parallel to the normal direction of the front panel 3a is formed on the outer surface of each panel constituting the case cover 4. The stripes are formed at predetermined intervals. By forming the groove in this way, the heat dissipation efficiency of the case cover 4 can be improved.

Then, the case body 3 and the case cover 4
And are connected by, for example, screwing. Also,
Each of the panels forming the case body 3 and the case cover 4 is formed of a heat conductive constituent material such as aluminum.

Opening H of the front panel 3a of the case 3 body
Reference numeral 2 is for collecting incident light to be incident on the color separation prism 10 described later, and has a substantially circular shape.
Further, a lens attachment portion 5 for detachably attaching a photographing optical system (not shown) to the solid-state imaging device 1 is provided outside the opening H2 of the front panel 3a. This photographing optical system is composed of various types of lenses and the like according to the application of the solid-state imaging device 1.

Further, the lens attachment portion 5 is formed with a substantially circular opening coaxial with the opening H2 of the front panel 3a. Further, a groove or the like for detachably mounting the photographing optical system is formed in the opening of the lens attachment section 5. Then, the opening H2 of the front panel 3a
A cover glass 6 made of optical glass is arranged in the solid-state imaging device 1 so as to prevent dust and the like from entering the solid-state imaging device 1.

The rear panel 3b is provided with a vent hole H3b for discharging gases such as water vapor and oxygen discharged from the electrolysis cell 8 described later to the outside of the case 2. Further, inside the back panel 3b of the case 2, an electrolysis cell 8 for arranging an electrochemical oxidative decomposition reaction of water vapor in the case 2 is arranged.

The electrolysis cell 8 will be described below.
FIG. 5 is a cross-sectional view schematically showing an example of the basic configuration of the electrolysis cell provided in the solid-state imaging device shown in FIG.

As shown in FIG. 5, the electrolysis cell 8 includes an anode 81 which is a gas diffusion electrode, a cathode 82 which is a gas diffusion electrode, and a polymer electrolyte membrane which is arranged between the anode 81 and the cathode 82. 83 and a voltage applying section 84 for applying a predetermined voltage between the anode 81 and the cathode 82.
The electrolysis cell 8 has a surface F81 on the side of the anode 81 which is not in contact with the polymer electrolyte membrane 83.
Is arranged so as to face the inside of the case 2, and the cathode 82
The surface F82 on the side not in contact with the polymer electrolyte membrane 83 is disposed so as to be exposed to the outside of the case 2.

The polymer electrolyte membrane 83 is not particularly limited as long as it is an ion exchange membrane which exhibits good ion conductivity in a wet state. Examples of the solid polymer material forming the polymer electrolyte membrane include a perfluorocarbon polymer having a sulfonic acid group (hereinafter referred to as a sulfonic acid type perfluorocarbon polymer), a polysulfone resin, a phosphonic acid group or a carboxylic acid group. A perfluorocarbon polymer or the like can be used. Of these, a sulfonic acid type perfluorocarbon polymer is preferable.

The anode 81 and the cathode 82 may be gas diffusion electrodes, and their structures are not particularly limited. For example, each of the anode 81 and the cathode 82 may have a configuration including a gas diffusion layer and a catalyst layer formed on these gas diffusion layers. As a constituent material of the gas diffusion layer, for example, a porous body having electron conductivity (for example, carbon cloth or carbon paper) is used. Further, the catalyst layer may have a structure mainly containing a fluorine-containing ion exchange resin and an aggregate of the catalyst coated with this fluorine-containing ion exchange resin. In this case, the catalyst used (catalyst in which metal is supported on carbon) is not particularly limited, but the metal supported on carbon is preferably a platinum group metal such as platinum or an alloy thereof. The carbon as the carrier is not particularly limited.

Further, the on-exchange resin contained in the catalyst layer is
It is preferably a sulfonic acid type perfluorocarbon polymer. The sulfonic acid-type perfluorocarbon polymer enables chemically stable and rapid proton conduction in the catalyst layer for a long period of time. And this anode 8
The ion exchange resin contained in 1 and the cathode 82 may be made of the same resin as the ion exchange resin constituting the polymer electrolyte membrane, or may be made of a different resin.

The voltage applying section 84 has a power source (not shown).
And a voltage control circuit (not shown) for controlling the applied voltage supplied from the power supply between the anode 81 and the cathode 82. Further, the voltage applying unit 84 is the image processing unit 7.
It is electrically connected to the central control unit 71 (see FIG. 9).

In the case of this electrolysis cell 8, the voltage applying section 8
By adjusting the applied voltage applied between the anode 81 and the cathode 82 from No. 4, the oxidation reaction of water represented by the following formula (1) is advanced in the anode, and the hydrogen ion represented by the following formula (2) is formed in the cathode. Promotes the reduction reaction of oxygen with oxygen. 2H ₂ O → 4H ⁺ + O ₂ ++ 4e ⁻ (1) 4H ⁺ + O ₂ ++ 4e ⁻ → 2H ₂ O (2) By adjusting the applied voltage, the hydrogen ion of the hydrogen ion shown in the following formula (3) The reduction reaction may be allowed to proceed, but from the viewpoint of operating the electrolysis cell 8 under the condition of lower power consumption, the formula (2) is used in the cathode.
It is preferable to proceed the reaction shown in. 2H ⁺ + 2e ⁻ → H ₂ (3) The magnitude of the applied voltage applied by the voltage applying unit 84 to advance the electrode reaction represented by the above formulas (1) and (2) is, for example, In addition to the overvoltage of each electrode reaction in the thermodynamic data such as the redox potential of the electrode reaction between the anode 81 and the cathode 82, the constituent material of the anode 81 and the cathode 82, the constituent material of the polymer electrolyte membrane 83, and the like. It is appropriately determined theoretically or experimentally in consideration of the water content, the temperature and humidity of the usage environment, and the like.

The electrolysis cell 8 is arranged on the inner side of the apparatus 1 than the electrolysis cell 8 and a fixing member 81 made of a continuous annular body and on the outer side of the apparatus 1 than the electrolysis cell 8. It is sandwiched between a fixed member 83 made of a continuous annular body. The fixing members 81 and 83 are integrated by screwing the respective outer edge portions with screws 83. The fixing member 81 is fixed to the bottom panel 3c.

The color separation prism 10 shown in FIG. 4 has a light receiving surface F10 facing the opening H2 of the front panel 3a, and the incident light L10 incident from the light receiving surface F10 is divided into, for example, three color components. The light L1 (for example, green light), L2 (for example, blue light), and L3 (for example, red light) are decomposed. The color separation prism 10 is made of, for example, an aluminum die cast material having high thermal conductivity.

The color separation prism 10 includes three compound prisms (dichroic prisms) assembled with a dichroic film (not shown) that reflects light of a specific wavelength interposed therebetween.
Of the color component optical paths 11, 12 and 13. For example, the dichroic film used in the color separation prism 10 shown in FIG. 4 includes one for red reflection that reflects a light component of a wavelength in the red region and one for blue reflection that reflects a light component of a wavelength in the blue region. Also transmits light components of wavelengths in the green region.

Therefore, the green light L1 goes straight in the color component optical path 11 in a direction parallel to the incident light L10, and the blue light L2 and the red light L3 are incident on the incident light L10 in accordance with the angle of the installation surface of the corresponding dichroic film. It travels in a direction different from the parallel direction. In the case of the color separation prism 10 shown in FIG. 4, the red light L3 travels in the color component optical path 13 toward the bottom panel 3c side, and the blue light L2 travels in the color component optical path 12 of the case cover 4. It is set to proceed toward the side.

The light L1, L2 and L3 of each color component
Are emitted from the light emission surfaces F11, F12, and F13 provided in the color component optical paths 11, 12 and 13, respectively for each of these color component lights.

As shown in FIG. 4, on the light emitting surfaces F11, F12 and F13 of the color separation prism 10, for example, CC
Solid-state imaging device 21, such as D (CHARGE COUPLED DEVICE),
22 and 23 are arranged adjacent to each other. The solid-state imaging devices 21, 22 and 23 are for converting the intensities of the lights L1, L2 and L3 of the respective color components incident on the respective light receiving surfaces into electric signals and outputting them to the image processing unit 7 which will be described later. This makes it possible to capture a one-dimensional or two-dimensional optical image. Each solid-state image pickup device 21, 22 and 2
The light receiving surfaces 3 are adhered to the light emitting surfaces F11, F12 and F13 of the color separation prism 10 in close contact with each other.

Further, as shown in FIG. 4, temperature sensors 91, 92 and 93 for detecting respective operating temperatures are connected to the solid-state image pickup devices 21, 22 and 23, respectively, and further, these temperatures are detected. The sensor is electrically connected to the central control unit 71 (see FIG. 9) of the image processing unit 7. Further, as shown in FIG. 4, a humidity sensor 9 for detecting the water vapor pressure (or relative humidity) in the case 2 is connected to the case 2, and the humidity sensor 9 is also connected to the image processing unit 7. Is electrically connected to the central control unit 71.

Further, as shown in FIG. 4, Peltier elements 31, 32 and 33 are arranged adjacent to the back surfaces F21, F22 and F23 of the solid-state image pickup elements 21, 22 and 23, respectively.

FIG. 6 is a system diagram schematically showing an example of the basic structure of the Peltier device shown in FIG. As shown in FIG. 6, in these Peltier elements 31, 32, and 33, a P-type semiconductor 36 is arranged between a metal plate 34 and a metal plate 37a, and an N-type semiconductor 36 is arranged between the metal plate 34 and the metal plate 37b. Semiconductor 3
It has a basic configuration in which 5 are arranged. Furthermore, the metal plate 3
7a and 37b are electrically connected by a conducting wire 38, and a constant current source 39 is electrically arranged in series on the conducting wire 38 between the metal plates 37a and 37b.

The Peltier elements 31 and 32 shown in FIG.
In accordance with the required cooling performance, 33 and 33 are a unit structure composed of the above-mentioned metal plate, P-type semiconductor, and N-type semiconductor, in which the P-type semiconductor and the N-type semiconductor are electrically connected in series, Specifically, it is configured by connecting a plurality of units in parallel.

Then, each Peltier element 31, 32 and 3
The constant current source 39 causes a direct current to flow from the metal plate 37b to the metal plate 37a through the metal plate 34, so that the metal plate 34 is interposed between the metal plate 34 and the metal plates 37a and 37b. A temperature difference that causes the metal plates 37a and 37b to have a low temperature can be generated. That is,
The Peltier elements 31, 32, and 33 are the solid-state image sensor 2
Heat h21 is pumped from 1, 22, and 23, and the metal plate 37
Each cooling block 41, 42 described later from the surface of a, 37b
And 43 to act as a heat pump that releases heat h41.

Further, each Peltier element 31, 32 and 33
Are electrically connected to the central control unit (see FIG. 9) of the image processing unit 7, and the output of each constant current source 39 is controlled. Furthermore, each solid-state image sensor 21,
Grease is applied between the back surfaces F21, F22, F23 of 22 and 23 and the surfaces of the metal plates 37a, 37b of the Peltier elements 31, 32, 33, respectively.
2 and 23 and the respective Peltier elements 31, 32 and 33 are in close contact with each other.

As shown in FIG. 4, each Peltier element 31,
Cooling blocks 41, 42, and 43 are arranged adjacent to each other on the back surfaces of 32 and 33, respectively. Further, inside the cooling block 41, a plastically deformable heat pipe 51 extending from one side panel of the case cover 4 is connected, and a plastically deformable heat pipe 52 extending from the other side panel is connected. . The heat pipes 51 and 52 are arranged substantially parallel to the normal line direction of the side panel to which they are connected, and the portion on the side connected to each cooling block 41 is the cooling block 41.
It is inserted in the inside of it while maintaining thermal contact.

Further, under the same arrangement conditions as the cooling block 41 and the heat pipes 51 and 52, the cooling block 4 is
Heat pipes 53 and 54 which can be plastically deformed are inserted in the interior of the cooling block 2 while keeping thermal contact with each other.
Heat pipes 55 and 56 are inserted into the interior of the unit 3 while maintaining thermal contact.

The cooling blocks 41, 42 and 43, and the heat pipes 5 will be described below with reference to FIGS. 4, 7 and 8.
1, 52, 53, 54, 55 and 56 will be described.

FIG. 7 is a perspective view showing a schematic basic structure of the cooling block shown in FIG. 1 and the heat conducting member (heat pipe) connected thereto. In particular, FIG. 7 shows the cooling block 41 shown in FIG. 1 and the heat pipes 53 and 54 inserted therein. Further, FIG. 8 is a sectional view schematically showing an example of the basic configuration of the heat pipe shown in FIG.

First, the heat pipes 51, 52, 53,
The configuration of 54, 55 and 56 will be described. Since the shape and configuration of each heat pipe are all the same, the heat pipe 51 will be described in the following description.

Each heat pipe 51, 52, 53, 54,
Reference numerals 55 and 56 connect the cooling blocks 41, 42 and 43 to the case cover 4 serving as a heat radiating plate, fix the positions of the solid-state image pickup devices 21, 22 and 23 in the case 2 and the cooling blocks 41, 42. It is a plastically deformable columnar heat conducting member including a heat transfer mechanism for transferring the heat of 42 and 43 toward the case cover 4.

As shown in FIG. 7, the heat pipe 51 is
For example, the pipe 57 is made of copper or the like and has a substantially circular ring-shaped cross section, and a working fluid (for example, water) enclosed in the pipe 57.
The working fluid is enclosed in a state in which the liquid 59 and the vapor 58 thereof coexist. The heat transfer mechanism of the heat pipe 51 utilizes the difference in enthalpy (latent heat) caused by the phase change between the liquid 59 and the vapor 58 of the working fluid enclosed in the pipe 57 to efficiently generate heat. From one to the other.

That is, the heat pipe 51 is the pipe 5
One of the ends of 7 is connected to a member to be cooled (cooling block 41 in this case) in a state of being capable of thermal contact,
The other is connected to a member (here, the case cover 4) for releasing heat pumped from the member to be cooled in a state capable of being in thermal contact. Here, as shown in FIG. 8, a portion of the end portion of the heat pipe 51 that comes into contact with the member to be cooled is the evaporation portion R1, and the other end portion on the opposite side of the evaporation portion R1 is the condensation portion R3. . Further, a region of the pipe 57 between the evaporating portion R1 and the condensing portion R3 of the heat pipe 51 is a heat insulating portion R2 for improving cooling efficiency.

Then, as shown in FIG. 8, vaporization of the working fluid preferentially progresses in the evaporation section R1, and liquefaction of the working fluid preferentially progresses in the condenser section R3. As a result, the water vaporized in the evaporating section R of the heat pipe 51 becomes a vapor flow FV, and this vapor flow FV is transmitted to the condensing section R3 via the heat insulating section R2 due to the difference in vapor pressure in the heat pipe 51, and then there. Liquefaction causes heat transfer. Due to the heat transfer using the vaporized vapor stream and the condensation by liquefaction, a much larger amount of heat is transferred than the heat transfer in the metal.

Next, each cooling block 41, 42 and 43
The configuration of will be described.

The cooling block 41 is for absorbing the heat emitted from the Peltier element 31 and radiating it to the evaporation portion R1 of the heat pipes 51 and 52. The cooling block 42 is for absorbing the heat emitted from the Peltier element 32 and radiating the heat to the evaporation portions R1 of the heat pipes 53 and 54. Further, the cooling block 43 is for absorbing the heat emitted from the Peltier element 33 and radiating the heat to the evaporation portions R1 of the heat pipes 55 and 56. Hereinafter, the cooling block 41 will be described as a representative.

As shown in FIGS. 4 and 7, the cooling block 41 is a substantially rectangular parallelepiped block, and one smooth surface of the cooling block 41 is in close contact with the back surface of the Peltier element 31. Further, as shown in FIG. 7, the cooling block 41 has two insertion holes 44 for inserting the heat pipes 51 and 52.
And 45 are formed.

These insertion holes 44 and 45 are respectively
It is a substantially columnar cavity that penetrates from one surface perpendicular to the surface of the cooling block 41 that is in close contact with the back surface of the Peltier element 31 to the surface facing this surface. Also, two insertion holes 44
And 45 are formed so as to be substantially parallel to each other.
Further, the cooling block 4 in which the insertion holes 44 and 45 are formed
The pair of surfaces of the case cover 4 facing each other face the inner surfaces of the side panels of the case cover 4 facing each other.

As shown in FIG. 7, the heat pipe 51 is connected to one of the surfaces of the case cover 4 which face each other so that the side of the condenser R3 can be thermally contacted. The side of the evaporation portion R1 is inserted into the cooling block 41.

The condenser R3 of the heat pipe 51 and the side panel of the case cover 4 are connected by a fixing member 61. The fixing member 61 is arranged in a groove (not shown) formed in the side panel of the case cover 4 and has a fitting insertion portion into which the condensation portion R3 of the heat pipe 51 is inserted. The fitting portion has a structure in which the portion of the condensing portion R3 of the heat pipe 51 is tightened from the side surface with the screw 71. Further, the screw 71 is attached to the case cover 4
It has a structure that fits into the groove formed in the.

On the other hand, the heat pipe 52 also has its condenser R3.
Is connected to the other surface of the side panels facing each other of the case cover 4 which is not connected to the heat pipe 51 by a fixing member 62 having a screw 72 so as to be capable of thermal contact and evaporation. The side of the portion R1 is inserted into the cooling block 41.

Here, the size and shape of the cross section of the insertion holes 44 and 45 are set so as to make thermal contact with the heat pipes 51 and 52 to be inserted, and preferably, these insertion holes are formed. The relationship between the size and shape of the cross section of the heat pipe and the heat pipe is set so as to be in the "tight fit" state in the "fitting method" of the hole and the shaft.

Further, as shown in FIGS. 6 and 7, a cutout portion is provided in a region near the case cover 4 in the insertion hole 44 of the cooling block 41. A part of the region of the cooling block 41 near the case cover 4 is shaved off, and a part of the side surface of the cylindrical cavity of the insertion hole 44 is opened to the outside.

As a result, when the heat pipe 51 is plastically deformed, the portion of the portion near the case cover 4 of the portion on the side of the evaporation portion R1 inserted into the insertion hole 44 projects outside the cooling block 41. Is possible. for that reason,
The degree of freedom of plastic deformation of the heat pipes 51 and 52 is further increased. As a result, when the color separation prism 10 to which the solid-state imaging device 21 and the Peltier device 31 are connected is mounted in the case 2, the solid-state imaging device 21 can be mounted smoothly without lowering the mounting position accuracy.

Furthermore, since the heat pipes 51 and 52 which are plastically deformed when the color separation prism 10 is attached do not apply any pressure to the solid-state image pickup device 21 during the operation of the apparatus 1, they do not apply pressure to the solid-state image pickup device 21. The element can be operated stably.

Here, a portion of the cooling block 41 that is cut off to form the cutout portion and a part of the insertion holes 44 and 45 is opened to the outside is a cooling block 41 that is in close contact with the back surface of the Peltier element 31. It is preferable that it is a portion on the side opposite to the surface.

By arranging the heat pipes 51 and 52 so as to satisfy the above arrangement conditions, the solid-state image pickup device 21 can be operated regardless of the posture of the solid-state image pickup device 1.
Can always be cooled efficiently. If the heat pipes 51 and 52 are arranged so as to satisfy the above arrangement condition, the installation space for the heat pipes 51 and 52 can be made sufficiently small.

Here, as shown in FIG. 4, the cooling blocks 42 and 43 are different in shape from each other.
Is a prismatic block having a pentagonal cross section, and the cooling block 42 is a prismatic block having a trapezoidal cross section.
The cooling block 41 has the same configuration as that of the above-described cooling block 41, and the cooling blocks 42 and 43 are also formed with insertion holes having the same shapes as the insertion holes 44 and 45 shown in FIGS. Has been done.

The image processing section 7 shown in FIG.
The solid-state image pickup devices 21, 22 and 23, the Peltier devices 31, 32 and 33, and the electrolysis cell 8 based on the detection signals sent from the sensors 1, 92 and 93 and the detection signal sent from the humidity sensor 9. Central controller 7 for controlling output
1 (see FIG. 9).

Further, the image processing section 7 shown in FIG. 4 is provided with an integrating circuit (not shown) for integrating the current signals output from the solid-state image pickup devices 21, 22 and 23 and converting them into voltage values. ing. As a result, in the solid-state imaging device 1,
A current signal having a value corresponding to the incident light intensity is applied to each solid-state image sensor 2
1, 22 and 23 respectively, the voltage value corresponding to the integrated value of this current signal is output from the integrating circuit, and the incident light intensity distribution is obtained and imaged based on this voltage value.

Further, the image processing section 7 includes the solid-state image pickup device 1
Even if the main power source (not shown) is turned off, a backup power source such as a secondary battery for performing a stop operation described later to prevent the occurrence of dew condensation is provided. The secondary battery is connected to a charge / discharge switching means (not shown) that is charged while the solid-state imaging device 1 is operating and discharges when the solid-state imaging device 1 is stopped. Is controlled by.

Further, the image processing section 7 may be provided with an A / D conversion circuit for converting the voltage value (analog value) output from the integration circuit into a digital value. In this case, the incident light intensity is obtained as a digital value, and it becomes possible to perform image processing by a computer or the like.

The central control unit 71 has a CPU, a ROM, and a RAM (none of which are shown). The CPU is composed of a microprocessor or the like and performs various kinds of arithmetic processing. A program for control / arithmetic processing is stored in the ROM in advance, and a RAM is used for reading / writing various data during the control / arithmetic processing.

Further, the central control unit 71 uses, for example, CP
It has an input / output port (not shown) connected to U. The solid-state imaging devices 21, 22, and 23 are connected to the input / output port.

The electrolysis cell 8 is connected to the input / output port via a control circuit for controlling the voltage applied to the electrolysis cell 8. Further, the Peltier elements 31, 32, and 33 are connected to the input / output port via a control circuit that controls the current flowing through these Peltier elements. Therefore, each of the solid-state image pickup devices 21, 22 and 23, the electrolysis cell 8, and each of the Peltier devices 31, 32 and 33 are given various signals generated by the arithmetic processing of the CPU via the input / output ports.

Further, at the input / output port of the central control unit 71, temperature sensors 91, 92 and 93 provided in the solid-state image pickup devices 21, 22 and 23 and a humidity sensor 9 provided in the case 2 are provided. For example, they are connected via an A / D conversion circuit. Then, the detection signals generated by these temperature sensor and humidity sensor are given to the CPU.

Further, the central controller 71 has a storage device (not shown), and this storage device is connected to the CPU via an input / output port. Then, the CPU controls the operation of the solid-state imaging device 1 by accessing the storage device and using the following data stored in the storage device as needed.

In this storage device, the solid-state image pickup elements 21, 22 and 23, the Peltier elements 31, 32 and 33, and the electrolysis cell 8 with respect to the water vapor pressure in the case 2 are included.
Data for independently controlling the start and stop timings of the are stored. In addition, the solid state image pickup devices 21, 22 and 23 and the Peltier devices 3 are included in the storage device.
After all 1, 32 and 33, and the electrolysis cell 8 are activated, data for activating them all steadily is stored.

That is, in the storage device, the condition that the water vapor pressure X1 in the case 2 is a predetermined value X0 which is equal to or lower than the saturated water vapor pressure (preferably less than the saturated water vapor pressure) at the operating temperature of each of the solid-state image pickup devices 21, 22 and 23. In order to satisfy the above, at the time of startup, the solid-state image pickup devices 21, 22 and 23 and the electrolysis cell 8 are started up before the respective Peltier devices 31, 32 and 33, and then a predetermined time has elapsed for the above conditions to be satisfied. Data for later activating each Peltier element 31, 32 and 33 is stored.

In the storage device, the solid-state image pickup devices 21, 22 and 23 are stored in the storage device more than the electrolysis cell 8 when stopped.
Data for stopping the Peltier elements 31, 32, and 33 first and then stopping the electrolysis cell 8 after a predetermined time when the above-described conditions are satisfied are stored.

Further, each Peltier element 3 is included in the storage device.
By controlling the outputs of 1, 32 and 33, each solid-state image sensor 2
Data is stored for adjusting the operating temperatures of 1, 22, and 23 to a predetermined temperature equal to or lower than the external environment temperature (preferably lower than the external environment temperature).

Further, the central control unit 71 has a timer (not shown), and this timer is connected to the CPU through an input / output port.

Then, the CPU uses the temperature sensors 91, 9
Based on the temperature detection signals of 2 and 93 and the humidity detection signal of the humidity sensor 9, the respective solid-state image pickup devices 21, 22 and 2
3, electrolysis cell 8, and each Peltier element 31, 3
The control signals to be sent to 2 and 33 are generated.

By the central control unit 71 and the like configured as described above, the electrolysis cell 8, the Peltier elements 31, 32 and 33, and the solid-state image pickup elements 21, 22 and 23.
Is reliably and accurately controlled so that dew condensation does not occur in the case 2.

Next, the operation of the solid-state image pickup device 1 will be described with reference to the flow charts shown in FIGS.

First, the case where the main power source (not shown) of the solid-state image pickup device 1 is turned on to operate the image processing section 7 to start the solid-state image pickup device 1 will be described. In this case, the CPU of the central control unit 71 outputs a drive signal to each of the solid-state image pickup devices 21, 22 and 23, and also the electrolysis cell 8
The drive signal is output to (S1). In this case, the output timing of the drive signal to each of the solid-state image pickup devices 21, 22 and 23 and the electrolysis cell 8 may be the same or different.

Next, the CPU inputs the detection signal of the water vapor pressure X1 in the case 2 transmitted from the humidity sensor 9 (S2). And the data of this water vapor pressure X1,
Each solid-state image pickup device 21, 22 and 23 set in advance
And a predetermined value X0 equal to or lower than the saturated water vapor pressure at the operating temperature are compared (S3). The predetermined value X0 is not particularly limited as long as it is equal to or lower than the saturated water vapor pressure at the operating temperature of each of the solid-state imaging devices 21, 22 and 23. For example, when the operating temperature is 0 ° C., the predetermined value X0 is 61P.
It is preferably a or less (10% or less when expressed in relative humidity).

Here, when the water vapor pressure X1 in the case 2 is larger than the above-mentioned predetermined value X0, the water vapor pressure X1 in the case 2 is not yet sufficiently reduced, and each Peltier element 31,
When it is determined that dew condensation may occur when 32 and 33 are activated, each Peltier element 31, 32 and 33 is not activated, and the electrolysis cell 8 and each Peltier element 31,
The operation state of 32 and 33 is maintained as it is, and step S2 and step S3 are repeated again.

On the other hand, when the water vapor pressure X1 in the case 2 is equal to or less than the above-mentioned predetermined value X0, each Peltier element 31,
It is determined that there is no risk of dew condensation even if 32 and 33 are activated, and the CPU sends a drive signal to each Peltier element 31, 32 and 33 (S4). As a result, the respective Peltier elements 31, 32 and 33 cool the respective solid-state image pickup elements 21, 22 and 23 and gradually adjust them to desired operating temperatures.

When each of the solid-state image pickup devices 21, 22 and 23 has reached a desired operating temperature, it is determined that a steady operating state has been reached, and the CPU responds to the load request and the entire solid-state image pickup device responds. Based on the data for steadily operating the solid-state image pickup device, new drive signals are sent to the solid-state image pickup devices 21, 22 and 2 respectively.
3, the Peltier elements 31, 32 and 33, and the electrolysis cell 8 are transmitted to start balanced control of the entire solid-state imaging device 1 (S5).

Next, a case where the main power source (not shown) of the solid-state image pickup device 1 is turned off and the solid-state image pickup device 1 is stopped will be described. In this case, the central controller 71 is operated by the backup power source such as the secondary battery described above.
Then, the CPU of the central control unit 71 controls the solid-state image sensor 2
1, 22 and 23, and each Peltier element 31, 32
And a stop signal is output to 33 to stop these operations (S6).

At this time, the CPU sends a driving signal to the timer to activate the timer, and the CPU of the central control unit 71 causes the solid-state image pickup devices 21, 22 and 23, and
The elapsed time from immediately after the stop of each of the Peltier elements 31, 32 and 33 is counted. In this case, the respective solid-state image pickup devices 21, 22 and 23 and the respective solid-state image pickup devices 21, 22 and 23 may be stopped at the same timing, or any one of them may be stopped first.

Next, when it is confirmed by the timer that the predetermined time has passed and the temperatures of the solid-state image pickup devices 21, 22 and 23 have risen sufficiently to prevent dew condensation, the CPU of the central control unit 71 Sends a stop signal to the electrolysis cell 8 (S7).

Here, each solid-state image pickup device 21, 22 and 2
Since 3 is operating at a predetermined temperature below the external environment temperature,
After the execution of step S6, the solid-state imaging devices 21 and 22 are
The temperature of 23 and 23 usually rises to the same value as the external environment temperature. Therefore, although the dew condensation is unlikely to occur, the dew condensation can be reliably prevented by delaying the stop timing of the electrolysis cell in step S7.

Incidentally, from the execution of step S6 to step 7
The time until the execution of is a time determined in advance by experiments or the like. The data of this time is stored in the storage device of the central control unit 71, and the CPU accesses the storage device to read and use it when executing steps 6 and 7.

In addition, each solid-state image pickup device 21, 22 and 23
Is monitored by the temperature sensors 91, 92 and 93, and from the execution of step S6, the solid-state imaging devices 21, 22
Further, a step of confirming whether or not the temperatures of 23 and 23 have risen to a predetermined temperature is further provided between the execution of step S6 and the execution of step 7, and the temperature of each solid-state image pickup device 21, 22 and 23 is set to a predetermined value. It may be set to execute step 7 when the temperature rises. In this case, the timer may be used to count the time, or the timer may not be used to count the time and the CPU may be configured to determine whether or not to execute step 7 based only on the temperature change.

Further, the water vapor pressure in the case after the execution of S6 is monitored by the humidity sensor 9, and the water vapor pressure in the case 2 is equal to or lower than the saturated vapor pressure at the external environment temperature (preferably less than the saturated vapor pressure at the external environment temperature). Is further provided between the execution of step S6 and the execution of step 7, and the water vapor pressure in case 2 is equal to or lower than the saturated vapor pressure of the external environment temperature (preferably saturated vapor of the external environment temperature). The setting may be such that step 7 is executed only when the pressure is less than the pressure. Also in this case, the timer may count the time, or the timer may not count the time and the CPU may determine whether or not to execute step 7 based only on the temperature change. Good.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments.

For example, when the solid-state imaging device 1 is activated, the time until the water vapor pressure X1 in the case 2 becomes equal to or less than the predetermined value X0 after the execution of step S1 is known in advance, and In S1, the CPU activates a timer to count the time from activation of each of the solid-state image pickup elements 21, 22 and 23 and the electrolysis cell 8, and executes step S4 after a predetermined time has elapsed. It may be set.

In the above embodiment, the case where the Peltier element is used as the cooling element has been described, but the cooling element used in the solid-state image pickup device and the method for operating the solid-state image pickup device of the present invention is not particularly limited to this. Not something. For example, a Stirling cycle engine may be used.

As the cooling element, for example, a thermally conductive container containing a cooling medium such as water or liquid nitrogen, a cooling medium whose temperature has risen in the container are taken out of the container, and a cooling medium having a low temperature is taken out. And a cooling medium circulating means for supplying the cooling medium into the container, and cooling the container by directly contacting the container with the solid-state imaging device or indirectly contacting the container with a predetermined thermally conductive member. May be adopted.

[0118]

As described above, according to the solid-state image pickup device and the method of operating the solid-state image pickup device of the present invention, even if the solid-state image pickup device is operated at a temperature lower than room temperature, the occurrence of dew condensation is surely prevented. be able to.

[Brief description of drawings]

FIG. 1 is a perspective view showing a preferred embodiment of a solid-state imaging device of the present invention.

FIG. 2 is a front view of the solid-state imaging device shown in FIG.

FIG. 3 is a rear view of the solid-state imaging device shown in FIG.

FIG. 4 is a cross-sectional view showing a schematic basic configuration of the solid-state imaging device taken along line II-II in FIG.

5 is a sectional view schematically showing an example of a basic configuration of an electrolysis cell provided in the solid-state imaging device shown in FIG.

FIG. 6 is a system diagram schematically showing an example of a basic configuration of the Peltier device shown in FIG.

FIG. 7 is a perspective view showing a schematic basic configuration of the cooling block shown in FIG. 1 and a heat conducting member (heat pipe) connected to the cooling block.

8 is a sectional view schematically showing an example of a basic configuration of the heat pipe shown in FIG.

9 is a control block diagram of the solid-state imaging device shown in FIG.

10 is a flowchart for explaining a control procedure of the solid-state imaging device shown in FIG.

FIG. 11 is another flowchart for explaining the control procedure of the solid-state imaging device shown in FIG.

[Explanation of symbols]

1 ... Solid-state imaging device, 2 ... Case, 3 ... Case body,
3a ... Front panel, 3b ... Rear panel, 3c ... Bottom panel, 4 ... Case cover, 5 ... Lens attachment part, 6 ... Cover glass, 7 ... Image processing part , 8 ... Electrolysis cell, 10 ... Color separation prism, 11, 12, 1
3 ... Color component optical paths 21, 22, 23 ... Solid-state image sensor,
31, 32, 33 ... Peltier element, 34 ... Metal plate, 3
5 ... n type semiconductor, 36 ... p type semiconductor, 37a, 37b
... Metal plate, 38 ... Closed circuit, 39 ... Constant current power source, 4
1, 42, 43 ... Cooling block, 44, 45 ... Insertion hole, 51, 52, 53, 54, 55, 56 ... Heat pipe, 57 ... Pipe, 58 ... Steam, 59 ... Liquid, 6
1, 62 ... Fixing member, 63, 64 ... Screw, 71 ... Central control device, 81 ... Anode, 82 ... Cathode, 83
... Polyelectrolyte membrane, 84 ... Power supply section, 85,86 ... Outer frame member, 87 ... Screw, F10 ... Light receiving surface of color separation prism, F11, F12, F13 ... Light emitting surface of color separation prism, F21, F22, F23 ... Rear surface of solid-state imaging device, FL ... Liquid flow, FV ... Vapor flow, L10 ... Incident light, L
1, L2, L3 ... Color component optical path, H2 ... Aperture, H3b
... Vents, h3, h21, h41 ... Heat, R1 ... Evaporating section, R2 ... Heat insulating section, R3 ... Condensing section.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // H01L 23/02 H01L 27/14 DF term (reference) 2H002 EB03 HA17 JA07 2H104 CC00 4M118 AA10 AB01 BA10 GC08 GD13 HA20 HA24 HA36 5C022 AB38 AB40 AC42 AC64 AC65

Claims (14)

[Claims] 1. A solid-state image sensor that photoelectrically converts light, a cooling element that is disposed adjacent to the solid-state image sensor and cools the solid-state image sensor, and at least the solid-state image sensor and the cooling element are housed. A case, an electrolysis cell for advancing an electrochemical oxidative decomposition reaction of water vapor in the case, and controlling the output of the cooling element to bring the operating temperature of the solid-state image sensor to a predetermined temperature equal to or lower than the external environmental temperature. Timing of adjusting and starting and stopping the solid-state imaging device, the cooling device, and the electrolysis cell so that the water vapor pressure in the case satisfies a predetermined value equal to or lower than a saturated water vapor pressure at the operating temperature. And a control device for controlling each of them independently. 2. The control device activates the solid-state imaging device and the electrolysis cell earlier than the cooling element at the time of activation, and then activates the cooling element after a predetermined time when the condition is satisfied. The solid-state imaging device according to claim 1, wherein. 3. The control device stops the solid-state imaging device and the cooling element before the electrolysis cell at the time of stop, and then stops the electrolysis cell after a predetermined time when the condition is satisfied. The solid-state imaging device according to claim 1, wherein 4. A humidity sensor for detecting the water vapor pressure in the case is further provided, and the controller controls the solid-state imaging device and the cooling device based on the water vapor pressure detected by the humidity sensor. The solid-state imaging device according to claim 1, wherein the start and stop timings of the element and the electrolysis cell are independently controlled. 5. A temperature sensor for detecting the temperature of the solid-state image sensor is further provided, and the control device is configured to detect the temperature of the solid-state image sensor based on the temperature of the solid-state image sensor detected by the temperature sensor. The start and stop timings of the cooling element and the electrolysis cell are independently controlled, and the output of the cooling element after startup is controlled.
4. The solid-state imaging device according to any one of 4 above. 6. The electrolytic cell comprises an anode that is a gas diffusion electrode, a cathode that is a gas diffusion electrode, a polymer electrolyte membrane disposed between the anode and the cathode, the anode and the cathode. The solid-state imaging device according to any one of claims 1 to 5, further comprising: a voltage applying unit that applies a predetermined voltage between and. 7. The solid-state imaging device according to claim 1, wherein the cooling element is a Peltier element. 8. A method of operating a solid-state imaging device, comprising: a solid-state imaging device that photoelectrically converts light; a cooling device that cools the solid-state imaging device; and a case that houses at least the solid-state imaging device and the cooling device. Then, the output of the cooling element is adjusted to adjust the operating temperature of the solid-state image sensor to a predetermined temperature equal to or lower than the external environmental temperature, and an electrolysis cell is provided to electrochemically decompose the water vapor in the case by electrochemical oxidation. By doing so, the start and stop timings of the solid-state imaging element, the cooling element, and the electrolysis cell are respectively adjusted so that the water vapor pressure in the case satisfies a predetermined value equal to or lower than a saturated water vapor pressure at the operating temperature. A method for operating a solid-state imaging device, which is characterized by performing independent adjustment. 9. At startup, the solid-state imaging device and the electrolysis cell are started up before the cooling device,
9. The method for operating a solid-state imaging device according to claim 8, wherein the cooling element is activated after a predetermined time when the condition is satisfied. 10. At the time of stop, the solid-state imaging device and the cooling element are stopped before the electrolysis cell, and then the electrolysis cell is stopped after a predetermined time when the condition is satisfied. The method for operating the solid-state imaging device according to claim 8 or 9. 11. A humidity sensor for detecting the water vapor pressure in the case is provided, and the start and stop timings of the solid-state imaging device, the cooling element, and the electrolysis cell are respectively determined based on the obtained water vapor pressure. The method for operating a solid-state imaging device according to claim 8, wherein the method is independently adjusted. 12. A timing sensor for detecting the temperature of the solid-state image sensor is provided, and the start and stop timings of the solid-state image sensor, the cooling element and the electrolysis cell are based on the obtained temperature of the solid-state image sensor. 12. The method for operating a solid-state imaging device according to claim 8, wherein the output of the cooling element after activation is adjusted independently of each other. 13. The electrolytic cell comprises an anode that is a gas diffusion electrode, a cathode that is a gas diffusion electrode, a polymer electrolyte membrane disposed between the anode and the cathode, the anode and the cathode. And a voltage applying unit that applies a predetermined voltage between the voltage applying unit and the voltage applying unit, the operating method of the solid-state imaging device according to any one of claims 8 to 12. 14. The method for operating a solid-state imaging device according to claim 8, wherein the cooling element is a Peltier element.