JPH1026790A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera capable of maintaining the performance of a battery over a long period by controlling the discharge quantity of a camera battery repeatedly discharged/charged in a state where the battery has a prescribed capacitance or more as remaining capacity. SOLUTION: Power is supplied from a main battery 34 to a camera circuit and an auxiliary battery 40 such as a size AA dry cell is charged so as to keep the main battery 34 a required charged state by a charger 80, as a charging power source. At this time, a charging current flowing into the main batter 34 is measured and a discharge current emitted from the main battery 34 is measured, to control the going in and out of the energy of the main battery 34 and inspect the remaining amount of the main battery 34. Further, a shot counter which is reset for zero when the main battery 34 reaches a fully charged state is used and the number of shots is increased according to a photographing operation, to inspect the remaining amount of the main battery 34. At this time, in an operation not reaching one shot, a consumption corresponding to a load is converted and added to the decimal fraction part of the shot counter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a camera having a power supply device capable of supplying a large capacity and a large current to a circuit such as a strobe or a film winding means using a rechargeable battery of a metal lithium series. About the camera.

[0002]

2. Description of the Related Art A conventional camera uses a manganese or lithium primary battery as a power source and a secondary battery such as a NiCd battery as a power source. Also, a power supply device for charging a secondary battery built in a camera using a solar cell has been proposed (JP-A-63-91641). However, a manganese primary battery has a low voltage, and therefore requires a plurality of batteries to obtain a high voltage, and it is difficult to obtain a large capacity current. However, there is a problem that it is not suitable for a camera which consumes a large current in recent years. Also,
Lithium-based primary batteries have the advantage of being able to obtain high voltage and large capacity current, but the batteries themselves are expensive and environmental problems at the time of disposal have been pointed out. Furthermore,
Lithium-based primary batteries are sometimes more difficult to obtain in travel destinations or overseas than manganese or alkaline primary batteries. In such cases, use the camera when the batteries are exhausted. There is a problem that it is necessary to give up or to carry a spare battery in advance in order to prevent such a situation, which is complicated.

[0003] Although charging of a primary battery is generally prohibited, as described in detail in JP-A-7-130400 and JP-A-8-84619, a lithium-based primary battery is used. Even under such conditions, charging can be performed safely under certain conditions. Lithium-based batteries (particularly metal lithium-based batteries) described in these publications are charged at a time rate current of about 2 μC to 5 mC when the remaining amount is within a range of 5 to 95% of the capacity C. By doing so, without impairing the properties of the original primary battery,
Charge and discharge can be repeated. In each of the above publications,
There is disclosed a technology in which a lithium-based primary battery and a solar battery are combined and applied to a camera, and the lithium-based primary battery is charged with electric power generated by the solar battery.

[0004] In the present specification, a battery having both characteristics of a primary battery and characteristics of a secondary battery is referred to as an "improved battery".
I will call it.

[0005]

However, in a power supply device having a solar cell, the solar cell itself is expensive, and it is necessary to expose the camera to high illuminance at the time of charging. There was a risk of doing. Furthermore, when the secondary battery (or improved battery) is rapidly consumed,
The problem that the camera cannot be used has not been solved because the amount of power generated by the solar cell is small and charging takes time.

From such a viewpoint, the present applicant has already proposed a power supply device having a configuration in which the improved battery is charged by an auxiliary battery such as an AA battery (Japanese Patent Application No. 7-2730).
No. 50). In order to use the improved battery effectively, it is desirable to appropriately manage the state of charge in consideration of the properties of the improved battery. The present invention has been made in view of such circumstances, and can supply a high voltage, a large capacity and a large current, and when the battery is exhausted, it is only necessary to replace only an inexpensive and easily available auxiliary battery. It is another object of the present invention to provide a camera capable of maintaining battery performance for a long period of time.

[0007]

According to a first aspect of the present invention, in order to achieve the above object, when the self-discharge rate of the primary battery is substantially equal and the remaining amount is equal to or greater than a predetermined capacity, the discharge and recharge is repeatedly performed. In a camera configured to supply power from a possible main battery to a plurality of power consuming means required for a photographing operation, an auxiliary battery for supplying charging energy to the main battery and an output voltage of the auxiliary battery are boosted. A booster for supplying power to the main battery via the booster and charging the battery; and measuring a charging current supplied from the auxiliary battery to the main battery via the booster. A charge amount measuring means for determining a charge amount supplied to the main battery; and a discharge amount for measuring a discharge current supplied from the main battery to the power consuming means to determine a discharge charge amount discharged from the main battery. Measuring means; A discharge amount monitoring unit that compares the charge amount obtained by the charge amount measurement unit with the discharge charge amount obtained by the discharge amount measurement unit, and monitors the remaining amount of the main battery so as not to fall below the predetermined capacity. It is characterized by having.

According to the present invention, power is supplied from the main battery to the power consuming means involved in the photographing operation, and the main battery is charged by the auxiliary battery. Therefore, as the auxiliary battery, a manganese-based AA battery or the like is used. By using an inexpensive and easily available battery, when the power supply (auxiliary battery) is exhausted, it is only necessary to replace the inexpensive auxiliary battery, which is more economical and environmentally friendly than replacing the main battery. There are advantages. In particular, by using a metal lithium secondary battery as the main battery, a large capacity and a large current can be supplied from the main battery to the power consuming means in the camera.
Since the natural discharge is small, the camera can be operated at the time of re-use even if the camera has not been used for a long time.

Further, since the output voltage of the auxiliary battery is boosted and applied to the main battery, the main battery can be charged by the auxiliary battery having a small voltage, and the electric energy of the auxiliary battery can be used without waste. . The charge current flowing into the main battery is measured by the charge amount measurement means, and the discharge current emitted from the main battery is measured by the discharge amount measurement means, so that the flow of energy in and out of the main battery can be grasped. Is monitored, it is possible to prevent the remaining amount of the main battery from falling below a predetermined electric capacity. Thus, the performance of the main battery as a storage battery can be maintained for a long period of time.

[0010] The auxiliary battery and the charging circuit may be a separate charging device separated from the camera, or may be integrated into the camera together with the main battery. In this case, it is preferable that the auxiliary battery is detachably provided so that it can be replaced when it is consumed. As a specific measure for monitoring the remaining amount of the main battery, a difference between the charge amount obtained by the charge amount measurement unit and the discharge amount obtained by the discharge amount measurement unit is obtained, and the difference is determined by a predetermined reference value. It is conceivable to make a judgment based on whether or not the value is lower than. Then, when the difference between the charged charge amount and the discharged charge amount becomes smaller than the predetermined reference value, the operation of the power consuming means is prohibited to prevent the main battery from discharging. As a result, it is possible to prevent the remaining amount of the main battery from falling below a predetermined electric capacity.

According to a third aspect of the present invention, in order to achieve the above object, an image is taken from a main battery which is substantially equal to the self-discharge rate of the primary battery and which can be repeatedly discharged and charged when the remaining amount is more than a predetermined capacity. In a camera configured to supply power to a plurality of power consuming means required for operation, an auxiliary battery for supplying charging energy to the main battery, and a booster for boosting an output voltage of the auxiliary battery, A charging means for supplying power to the main battery through the boosting means and charging the battery; and a shot for taking a series of photographing operations accompanying the release operation as one shot and adding and counting the number of shots for each release operation A counter, reset means for resetting a count value of the shot counter to zero when the main battery reaches a fully charged state by the charging means, and Based on the count value of the counter, it is characterized in that the remaining amount of the main battery is and a discharge amount monitoring means for monitoring so as not to fall below the predetermined capacity.

According to the present invention, when the main battery reaches a fully charged state (full charge state), the shot counter is reset to 0, and the number of shots is reduced by one each time shooting is performed by a release operation. Increment by one.
That is, the amount of energy consumed by the photographing operation is counted in units of one shot, so that the amount of discharge of the main battery is estimated. Then, the remaining amount of the main battery is monitored based on the count value. As a result, the remaining amount of the main battery can be prevented from falling below a predetermined capacity, and the performance of the main battery as a storage battery can be maintained for a long time.

As a specific measure for monitoring the remaining amount of the main battery so that the remaining amount does not fall below a predetermined capacity, a first value indicating the level of the remaining amount is shown in the count value of the shot counter.
If the count value exceeds the first reference value, a warning may be given by a display means such as a lamp or a liquid crystal display panel. In addition, a second boundary value indicating the level of the remaining amount of the main battery is set, and when the count value exceeds the second boundary value, the operation of the power consuming means is prohibited to release the current from the main battery. , The remaining amount of the main battery can always be maintained at a predetermined electric capacity or more.

According to a sixth aspect of the present invention, a fractional part of less than one shot is provided in the count value of the shot counter.
When at least one of a series of shooting operations constituting one shot is performed, the amount of energy consumed according to the operation is converted into an energy ratio for one shot and added to the decimal part of the shot counter. I have. Thus, the remaining amount of the main battery based on the count value can be more accurately estimated.

Further, by converting the amount of energy consumed for maintaining the spontaneous discharge of the main battery or the standby state of the camera into an energy ratio for one shot with the lapse of time, and adding it to the decimal part of the shot counter,
The remaining amount of the main battery can be grasped more accurately. In order to accurately correspond the count value of the shot counter to the remaining amount of the main battery, the count value of the shot counter is increased in accordance with an increase in the energy stored in the main battery when electric energy is supplied from the auxiliary battery to the main battery. By decrementing at any time, the count value can be set to a value corresponding to the remaining amount of the main battery without necessarily resetting the count value by full charge.

According to the ninth aspect of the present invention, since the main battery is inevitably deteriorated gradually during long use, the life of the main battery itself is determined by the total shot counter. The total shot counter is not decremented by charging the main battery, and keeps incrementing the shot number while using one main battery. When the count value reaches a preset limit value, it is determined that the life of the main battery has expired, and a display for prompting replacement of the main battery is performed.

It is preferable to display both the remaining amount or the replacement time of the main battery and the remaining amount or the replacement time of the auxiliary battery. By providing the respective display means separately and independently, the user can understand. It will be easy. In addition, a liquid crystal display panel is used as a means for displaying the remaining amount or replacement time of the main battery and the remaining amount or replacement time of the auxiliary battery, and the shape of the auxiliary battery is displayed inside the first figure simulating the shape of the main battery. By displaying the second figures that are similar to each other in an overlapping manner, there is an advantage that the display area of the liquid crystal display panel can be saved in space, and that both display contents can be easily recognized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the camera according to the present invention will be described below in detail with reference to the accompanying drawings. FIG.
3 is an internal perspective view of the camera to which the present invention is applied, FIG. 1 is a front view, FIG. 2 is a top view, and FIG. 3 is a left side view. A reference numeral 12 at the center of the camera 10 shown in FIG. 1 denotes a lens barrel housing section for housing a photographing lens barrel (not shown), and a film cartridge (not shown) on the right side of the lens barrel housing section 12. ) Is formed, and a film take-up chamber 16 is formed on the left side. A flash device 18 is provided at an upper portion of the cartridge chamber 14, that is, at an upper right corner of the front of the camera. On the left side of the strobe device 18, an AF light emitting unit 20,
An AF light receiving unit 22 and a finder unit 24 are provided.

The cartridge chamber 14 is provided with a spool drive shaft 26 which is engaged with a spool of a film cartridge loaded in the chamber. On the other hand, the film take-up chamber 16 is provided with a take-up spool 28 for taking up the film sent from the film cartridge,
A film feed motor 30 is incorporated in the take-up spool 28. The rotational force of the film feed motor 30 is transmitted to the take-up spool 28 and
Are transmitted to the spool drive shaft 26 via gear trains 32A, 32B,... 32I, 32J shown in FIG.

That is, when the film feeding motor 30 rotates forward, the film is fed from the film cartridge loaded in the cartridge chamber 14 and the winding spool 2 is rotated.
8 When the film feeding motor 30 is reversed, the spool driving shaft 26 of the cartridge chamber 14 is rotated.
Is reversed, and the film wound on the winding spool 28 is rewound into the film cartridge. The rotation of the film feeding motor 30 is controlled by a control device including a central processing unit (CPU) 70, which will be described later, and one frame feed (winding up) and rewinding of the film are performed.

On the left side of the take-up spool 28, a main battery 34 and a main capacitor 36 for supplying power to various circuits in the camera are arranged vertically one above the other. That is, the main battery 34 is placed above the cylindrical main capacitor 36.
Are arranged coaxially side by side. In addition, a partition plate 38 is provided between the main battery 34 and the main capacitor 36.

The main battery 34 is a rechargeable battery dedicated to a camera having a small self-discharge, and is an improved battery having both characteristics of a primary battery and a secondary battery. Although the configuration of the main battery 34 will be described in detail later, for example, a battery having a self-discharge rate of 5% / year or less is used, and its voltage is 3.2 V when properly charged. The shape of the main battery 34 is not particularly limited, but is formed, for example, in the same shape as a current CR2-type battery.

An auxiliary battery 40 for supplying charging energy to the main battery 34 is arranged behind the main battery 34 and the main capacitor 36 (see FIG. 3). Auxiliary battery 40
Are arranged vertically in parallel with the arrangement direction of the main battery 34 and the main capacitor 36. In addition, the camera 10
A battery cover 42 is provided on the shaft 42A so as to be openable and closable at a rear corner of the battery pack 42. An auxiliary battery 40 is stored in an auxiliary battery storage chamber formed inside the battery cover 42. By opening the battery cover 42, the auxiliary battery 40 stored in the auxiliary battery storage chamber can be taken out and replaced. Further, with the auxiliary battery 40 taken out, the main battery 34 disposed at the back can be taken out. The battery cover may be provided on the back or bottom of the camera 10.

The auxiliary battery storage room is, for example, one AA
A manganese-based AA battery is housed as the auxiliary battery 40. The auxiliary battery 40 is not limited to an AA battery, but may be a primary battery of another form. However, manganese-based AA batteries are widely used and can be easily obtained at low cost anywhere in the world. There are advantages.

In FIG. 1, reference numeral 43 denotes a camera control circuit, reference numeral 44 denotes a boosting circuit for charging, and reference numeral 46 denotes a mounting space for a charging circuit for the main capacitor 36. The power supply of the camera 10 is the main battery 3
4, an auxiliary battery 40, a booster circuit 44, and the like, and power is supplied from the main battery 34 to the strobe device 16, the film feeding motor 30, the zoom motor 48, the control circuit 43, and the like.

Next, the main battery will be described. Main battery 3
4, the improved battery is used as described above. As the positive electrode active material of the improved battery, manganese dioxide is preferable, and particularly, manganese dioxide synthesized by electrolysis and manganese dioxide chemically synthesized are preferable. As a material that can be used as the negative electrode active material, lithium metal and lithium alloy (any metal that forms an alloy with lithium may be used, but Al, Mn, Sn, Mg, Cd, and In are particularly preferable, and an alloy containing Al is particularly preferable). Preferably, it is used.

A conductive agent, a binder, a filler and the like can be added to the electrode mixture. The conductive agent may be any electronic conductive material that does not cause a chemical change in the configured battery. The addition amount is not particularly limited,
It is preferably from 1 to 50% by weight, particularly preferably from 2 to 30% by weight. As the binder, a polysaccharide, a thermoplastic resin, a polymer having rubber elasticity, or a mixture thereof can be used. The amount of the binder added is not particularly limited, but is preferably 1 to 50% by weight, and particularly preferably 2 to 30% by weight.

As the filler, any fibrous material that does not cause a chemical change in the constructed battery can be used. Usually, fibers such as olefin-based polymers such as polypropylene and polyethylene, glass, and carbon are used. Although the amount of the filler is not particularly limited,
~ 30% by weight is preferred. The non-aqueous electrolyte is generally composed of a solvent and a lithium salt (anion and lithium cation) dissolved in the solvent, and comprises propylene carbonate and / or butylene carbonate and 1,2-dimethoxyethane and / or diethyl carbonate. An electrolyte containing LiCF ₃ SO ₃ , LiClO ₄ , LiBF ₄ and / or LiPF ₆ in the mixed solution of the carbonate is preferable. The amount of these electrolytes to be added to the battery is not particularly limited, but may be used in a required amount depending on the amounts of the positive electrode active material and the negative electrode active material and the size of the battery.

The volume ratio of the solvent is not particularly limited,
In the case of a mixture of propylene carbonate and / or butylene carbonate to 1,2-dimethoxyethane,
0.4 / 0.6 to 0.6 / 0.4 is preferred. The concentration of the supporting electrolyte is not particularly limited, but may be 0.1 to 1 liter of the electrolytic solution.
2-3 moles are preferred. The metal lithium-based battery having such a configuration has a self-discharge rate as small as that of a primary battery, and when discharged from a fully charged state to below a specified energy value, it functions as a secondary battery thereafter. Has a property of rapidly decreasing. The amount of discharged energy is represented by the usage rate with respect to the total energy, with the fully charged electric capacity as the reference 100, and is referred to as “depth of discharge”.

According to the experiment, when the discharge and the charge are repeated within the range where the depth of discharge does not exceed 5%, the deterioration of the main battery is small, the cycle life is large, and photographing of 3000 shots or more is sufficiently possible. . On the other hand, when used at a discharge depth of 30%, the performance of the main battery as a secondary battery is reduced, and the cycle life is shortened. In this case, only about 1000 shots can be repeatedly shot. As the depth of discharge increases, the cycle life sharply decreases,
Further, once the depth of discharge is deeply discharged, the performance as a storage battery decreases, the electric capacity stored in the main battery by subsequent recharging decreases, and the cycle life also decreases.

That is, it is desirable to use the main battery so as to repeatedly discharge and charge the battery within a shallow depth of discharge range. Therefore, when this improved battery is actually used, a proper depth of discharge is set in accordance with the setting of the limit of use as a camera, and management is performed so that discharge and charge are repeated so as not to exceed the range of the depth of discharge. There is a need to. FIG. 4 shows an example of the configuration of a charging circuit for charging main battery 34 with auxiliary battery 40. The charging circuit 50 includes a charging control circuit 52 and a boosting circuit 54 as shown in FIG.
The charging control circuit 52, respectively detects a voltage V _CR and the voltage V _E of the auxiliary battery 40 of the main battery 34, for example, a main battery 34
The voltage V _CR, becomes smaller than the voltage value 3.25V full charge state (V _CR <3.25 V), and voltage of the auxiliary battery 40 V
_{When E} is V _E ≥ 0.9 V (the end voltage of the auxiliary battery 40), the booster circuit 54 is operated to charge the main battery 34.

On the other hand, the charging control circuit 52 is mainly when the battery 34 is fully charged (when becomes a voltage V _CR = 3.25 V), or the voltage V _E of the auxiliary battery 40 is exhausted auxiliary battery 40 is V _{When E} <0.9V, the boosting circuit 54 is stopped. Further, the charge control circuit 52 outputs a signal indicating the voltage of the auxiliary battery 40 to the display control circuit 62 in order to display the remaining amount of the auxiliary battery 40 on the liquid crystal panel 60.

The display control circuit 62 receives the signal indicating the voltage of the auxiliary battery 40 from the charge control circuit 52 as described above, and outputs a signal from a film counter indicating the remaining amount of the film, a strobe switch, a shutter button, and a self-timer. Signals from the switches are applied, and the liquid crystal panel 60 performs required display based on these input signals. The display contents of the liquid crystal panel 60 will be described later in detail. The charge control circuit 52 is connected to the main battery 3
4 supplies drive power.

Next, the boosting circuit 54 will be described. FIG. 5 is a circuit diagram showing an example of the booster circuit. As shown in the figure, the booster circuit 54 is of a push-pull type, and the power source of the auxiliary battery 40 is
2, the current is converted into alternating current by the transistors Q 1 and Q 2 which are alternately turned on by the transistor T 2, and the voltage is boosted via the transformer T.
By rectifying by 5, the DC voltage is converted to a DC voltage necessary for charging the main battery 34.

Here _, assuming that the number of turns on the primary side and the secondary side of the transformer T is n _1, n ₂ , the voltage V on the primary side of the transformer T is
₁ and the voltage V ₂ on the secondary side are expressed by the following equation (1):

[0036]

## EQU1 ## There is a relationship of V ₁ / V ₂ = n ₁ / n ₂ (1). On the other hand, the voltages V ₁ and V ₂ required on the primary side and the secondary side of the transformer T are:

[0037]

## EQU2 ## V ₁ = 0.9−V _DS = 0.7 [V] (Min) (2)

[0038]

V ₂ = 3.25 + 0.7 × 2 + 0.5 = 5.15 [V] (3) (provided that 0.9 is the final voltage of the auxiliary battery 40) V _{DS is} the saturation voltage between the drain and source of the transistors Q1 and Q2 3.25: The maximum voltage of the main battery 34 is 0.7 × 2: the voltage drop in the rectifier circuit 55). Therefore, the turns ratio n ₂ / n ₁ of the transformer T is

[0039]

## EQU4 ## n ₂ / n ₁ = V ₂ / V ₁と 7.3 (4) As described above, the charging circuit 50 shown in FIG. 4 transfers the charging energy of the auxiliary battery 40 to the main battery 34 every time the voltage V _CR of the main battery 34 becomes V _CR <3.25 V, and Charge. Then, when the main battery 34 is fully charged (when the voltage V _CR becomes 3.25 V), the charging operation is stopped.

After the main battery 34 is fully charged,
When the electric capacity of the main battery 34 decreases due to the use of the camera, the charging energy is transferred from the auxiliary battery 40. The electric capacity of the main battery 34 increases with the charging time, and the electric capacity of the auxiliary battery 40 decreases. Thus, the main battery 34
The energy of the auxiliary battery 40 is transferred to the main battery 34 in accordance with the energy consumption of the main battery 34, so that the main battery 34 is always kept in a state close to full charge.

By doing so, there is an advantage that the main battery 34 can be easily handled without fear of over-discharge deterioration. Further, since the main battery 34 is a lithium-based battery,
As compared with the auxiliary battery 40, a high voltage and a large current can be supplied to the camera, so that a camera requiring a large current can be supported, and the charging time of the strobe can be shortened.

When the charge energy of the auxiliary battery 40 is transferred to the main battery 20 and the capacity of the auxiliary battery 40 reaches almost 0 (when the voltage of the auxiliary battery 30 reaches its final voltage 0.9 V), Unless you replace the auxiliary battery 40,
The charging energy is not supplied from the auxiliary battery 40 to the main battery 34. However, the main battery 34 has its voltage V
_{Since the CR} is maintained in a state of charge close to full charge, there is a certain amount of electricity that can be consumed (for example, an amount of electricity capable of taking 100 shots) until the voltage V _CR reaches a predetermined battery check level. doing. Therefore, the camera can be continuously used without immediately replacing the auxiliary battery 40 with a new one.

Also, when replacing the auxiliary battery 40, the auxiliary battery 40 may be an AA dry battery, and thus has an advantage that it can be easily obtained at low cost anywhere in the world.
Further, since the charging circuit 50 has the boosting circuit 54,
AA batteries that have been used in other devices can be used to some extent. In this embodiment, when the voltage V _CR of the main battery 34 falls below 3.25 V, the auxiliary battery 4
Although the zero charging energy is transferred to the main battery 34, the present invention is not limited to this, and charging may be started after the voltage of the main battery 34 reaches a predetermined voltage value (for example, 3.0 V). Alternatively, the number of shots after the state of full charge may be counted, and when the number of shots reaches a predetermined value (for example, 100 shots), the charging energy of the auxiliary battery 40 may be transferred to the main battery 34. However, in this case, the charge control circuit 62 needs to receive a signal indicating the number of shots from the camera.

FIG. 6 is a block diagram showing the configuration of the control system of the camera. A central processing unit (CPU) 70, which plays a central role of a control system, receives various signals indicating an operation state of the camera including an ON / OFF state of a main switch Sm and a release switch Sr, and also performs shutter drive. Circuits (hereinafter, collectively referred to as "camera circuits") corresponding to various operations of the camera, such as a circuit 72, a strobe circuit 74, and a film feeding circuit 76, are connected. CPU 70
The camera operates when supplied with power from the main battery 34, controls the operation of the camera circuit, and also has a role of a counter for counting the number of shots.

The CPU 70 has an EEPROM 78 from which data can be read and written, and a liquid crystal display panel (L display) for displaying the status of the camera and inputting the mode setting.
CD) 60 is connected. That is, the CPU 70
Are the display control circuit 62 and the charge control circuit 52 shown in FIG.
Will also play a role. The charger 80 for transferring the energy of the auxiliary battery 40 to the main battery 34 includes a booster circuit 5
4 and a constant current circuit 82.
It is controlled by a charge control signal output from 70. A switch 84 that is turned on / off in response to a charge control signal from the CPU 70 is provided between the charger 80 and the main battery 34. And
When a charge control signal for instructing charge execution is added from the CPU 70, the boosting circuit 54 operates and the switch 84 is turned on, so that energy transfer from the auxiliary battery 40 to the main battery 34 is permitted. When a charge control signal instructing that charging is not performed is output from the CPU 70, the operation of the booster circuit 54 is stopped, and the switch 84 is turned off, so that energy transfer from the auxiliary battery 40 to the main battery 34 is prohibited. You.

The positive electrode of the main battery 34 is connected to an input terminal of a comparator 88 via a switch 86 which is turned on / off according to a control signal from the CPU 70. When the switch 86 is turned on, the voltage of the main battery 34 is Is divided and applied to the input end of the comparator 88. Comparator 88
A constant voltage Vs is applied to the other input terminal, and the comparator 88 notifies the CPU 70 of a comparison result between the divided voltage value of the main battery 34 and the predetermined voltage Vs. Thereby, the voltage of the main battery 34 can be monitored.

Next, a method of managing the remaining amount of the main battery will be described. FIG. 7 is a block diagram showing a configuration of a management unit for managing the charge amount and the discharge amount of the main battery. The management means shown in the figure monitors the charging energy charged from the auxiliary battery 40 to the main battery 34, monitors the discharging energy discharged from the main battery 34, and based on a comparison between the two, the remaining power of the main battery 34 is monitored. It is to grasp the quantity.

The charging energy of the auxiliary battery 40 is transferred to the main battery 34 via the charger 80, the resistor R1, and the constant voltage diode ZD. The voltage across the resistor R1 is applied to a differential amplifier 92, and the output of the differential amplifier 92 is guided to a CPU 70 via an A / D converter 93. The electric energy released from the main battery 34 is guided to the camera circuit 94 via the resistor R2, and is consumed in the camera circuit 94. The voltage across the resistor R2 is equal to the differential amplifier 96.
The output of the differential amplifier 96 is applied to a CPU 70 via an A / D converter 97.

According to this configuration, when a current is supplied from the auxiliary battery 40 to the main battery 34 via the charger 80, the charging current flows through the resistor R1. If the monitoring is performed, the charge amount charged in the main battery 34 is obtained. That is, assuming that the voltage across the resistor R1 is VR1, the charge amount QI charged in the main battery 34 is given by the following equation (5).

[0050]

## EQU5 ## QI = ∫VR1 / R1 × Δt (5), and the charge amount QI can be obtained by performing an integral operation every time Δt during which the charging current flows. On the other hand, the power for operating the camera circuit 94 is:
Since the voltage is supplied from the main battery 34 to the camera circuit 94 via the resistor R2, if the voltage at both ends of the resistor R2 is monitored by the differential amplifier, the amount of electric charge supplied from the main battery 34, that is, the discharge The quantity (consumption) can be determined.

That is, assuming that the voltage between both ends of the resistor R2 is VR2, the discharge charge amount QD discharged from the main battery 34 is expressed by the following equation (6).

[0052]

## EQU6 ## QD = ∫VR2 / R2 × Δt (6) The discharge charge amount QD can be obtained by performing an integral operation every time Δt during which the discharge current is flowing. The difference .DELTA.Q between the charge amount QI obtained by the equation (5) and the discharge amount QD obtained by the equation (6) is obtained, and the charge amount and the discharge amount are compared. That is, the difference ΔQ = (charged charge amount Q
It is monitored whether or not (I-discharge charge amount QD) falls below a predetermined level A.

The value of the predetermined level A is a value which is set in advance and stored in the ROM or the EEPROM 78 of the CPU 70, and ΔQ becomes smaller than the level value A.

[0054]

When ΔQ = (charge charge amount QI−discharge charge amount QD) <A (7), the shutter is locked so as not to accept the release operation, and photographing is prohibited. It is also possible to set a plurality of level values for monitoring the discharge amount of the main battery 34 stepwise, and to display a remaining amount or a warning display according to the amount of energy stored in the main battery 34 at each stage. Conceivable.

Next, a method of managing the amount of discharge of the main battery by the number of shots in which shooting has been performed will be described. When the release operation is performed, normally, as shown in FIG. 8, the focusing operation is started by AF, and then the shutter is opened, the flash is fired, the shutter is closed, the photographing lens position is returned, the film is fed one frame, and the flash is charged continuously. Executed
After the strobe charge is completed, the system enters the standby state. This series of operations is defined as one shot, and the amount of charge and the amount of discharge can be grasped in units of electric energy consumed in one shot.

For example, when the flash operation is not performed by the release operation because the steady light is bright or the like, it is unnecessary to charge the flash after one frame is fed, so that the flash is consumed compared to the defined one shot. The amount of energy is small. Therefore, with the energy ratio for one complete shot,
Convert to 0.2 shots. In addition, even when there is no camera operation input, the clock function may be operating. Even when only the CPU 70 is operating while waiting for an operation input, the power consumption is low, but the energy of the main battery 34 is consumed. Have been. Accordingly, the power consumed in the no-operation state is obtained from the circuit current × time t according to the elapsed time of the no-operation time, and converted into an energy ratio for one shot, for example, 0.01 shots when the standby time elapses T1. .

Further, the energy of the main battery 34 slightly decreases with time due to a change in chemical composition or spontaneous discharge to the atmosphere. Although the improved battery has a self-discharge rate as small as a primary battery, it cannot be completely neglected. Therefore, the amount of energy lost over time T in consideration of self-discharge is calculated as an energy ratio with respect to one shot. For example, when the time T2 elapses, it is converted into a condition of 0.01 shot. In this way, the electric capacity consumed for less than one shot is represented as a decimal part of the shot counter, and the decimal part of the shot counter is incremented in accordance with the operation state of the camera and the passage of time to discharge the main battery 34. The amount can be managed based on the count value of the shot counter.

The count value of the shot counter is EEPR
The count value is stored in the OM 78, and the count value is incremented for each shot, and the fractional part thereof is incremented with the lapse of time as described above. When the main battery 34 is charged, the count value is decremented according to the charging time (charging amount).
The charge amount of the main battery 34 is calculated by the following equation (8).

[0059]

[Equation 8] Charge amount = Charge current × Charge time × Efficiency (8) On the other hand, the detection of the remaining amount of the auxiliary battery is applied a known battery check method, a current flows in a internal resistive load, detects a battery voltage across value V _E at this time. When _VE is smaller than a predetermined value, a warning is issued.

Next, the display contents of the liquid crystal panel 60 will be described. FIG. 9 shows an example of the display contents of the liquid crystal panel 60. The liquid crystal display panel 60 has a graphic display section 6 imitating the shape of an auxiliary battery (AA battery).
02 is provided to display the remaining amount of the auxiliary battery 40 or the replacement time. Specifically, based on a signal indicating the voltage of the auxiliary battery 40 output from the charge control circuit 52 shown in FIG. 4, the display control circuit 62 turns the graphic display unit 602 on, off, on, off, on and off. The display is switched step by step to inform the user of the remaining amount of the auxiliary battery 40 and to prompt the user to replace the battery.

The main battery (CR) is provided on the liquid crystal panel 60.
Graphic display section 6 imitating the shape of (2 identical batteries)
04 is provided to indicate the remaining amount of the main battery 34 or the replacement time. However, unlike the auxiliary battery 40, the main battery 34 is not replaced frequently by the user.
Since it is used as a built-in battery of the camera, it is not necessary to constantly display the remaining amount of the main battery 34. Therefore, the graphic display unit 604 for the main battery 34
It is normally turned off, and when the capacity of the auxiliary battery 40 reaches almost 0 and the charging energy from the auxiliary battery 40 is no longer supplied to the main battery 34, it is fully lit, and the consumption is consumed until the replacement of the auxiliary battery 40. Let us indicate the possible electricity quantities. In addition to this display, the number of images that can be photographed when the auxiliary battery 40 is not replaced is displayed on the display unit 605.

As described above, even if the auxiliary battery 40 is exhausted, the main battery 34 has a certain amount of electricity that can be consumed (for example, the amount of electricity that can take 100 shots). It is possible to continue shooting even after exhaustion. Therefore, when the auxiliary battery 40 is exhausted, for example, the number of recordable images “99” is displayed on the display unit 605, and thereafter, the number of recordable images is counted down by one for each shot.

The liquid crystal panel 60 displays the remaining film amount on the display unit 606 so that the number of recordable images and the remaining film amount are not confused.
The display of the remaining amount of the film is displayed in characters larger than the display of the number of shootable images. By separately providing the battery check (BC) display section (602) of the auxiliary battery 40 and the BC display section (604) of the main battery, the user can clearly recognize which battery has been exhausted. be able to.

The liquid crystal panel 60 also has a strobe mode display section 608 for displaying a strobe mode such as an automatic light emission mode, a red-eye reduction mode, and a backlit shooting mode in order from the upper left, and when the photographic lens is set for long-distance shooting. 610, a long-distance mode display section 610 that lights up when the timer mode is set.
2, and a date display unit 614 for displaying a date, a time, and the like. The display unit 605 for displaying the number of shootable images is shared as a part of the date display unit 614 and is also shared as a display unit of the subject distance in the manual focus (MF) mode.

The method of displaying the number of images that can be photographed is not limited to the above-described embodiment. For example, the voltage of the main battery 34 may be detected and displayed based on the detected voltage. Further, the display of the number of images that can be taken is not limited to numbers, but may be displayed graphically so that the approximate number of images can be recognized. FIG. 10 shows another display mode in which the remaining amount of the auxiliary battery 40 and the remaining amount of the main battery 34 are displayed on the liquid crystal panel 60.
As shown in the figure, a configuration is adopted in which a second graphic 630 simulating the shape of the auxiliary battery 40 is superimposed and displayed inside a first graphic 620 simulating the shape of the main battery 34.

When the remaining amount of the auxiliary battery 40 is sufficient, as shown in FIG.
The display section of the second figure 630 provided inside 0 is all turned on. Then, as the remaining amount of the auxiliary battery 40 decreases, the first half of the second graphic 630 is turned off (that is, turned on half). Further, when the remaining amount of the auxiliary battery 40 decreases and reaches the final voltage, the second graphic 620 is completely turned off as shown in FIG. Is displayed. By the graphic display shown in FIG.
The approximate number of images that can be photographed without replacing the auxiliary battery 40 can be recognized.

As described above, by displaying the second figure 630 simulating the shape of the auxiliary battery 40 on the inside of the first figure 620 simulating the shape of the main battery 34, the display area of the liquid crystal panel 60 is displayed. Can be saved in space, and both display contents can be easily recognized. Next, processing of the camera configured as described above will be described.

FIG. 11 shows a flow of a battery check process of the auxiliary battery 40. The remaining amount of the auxiliary battery 40 is detected by measuring the voltage V _E across the battery during the period when current is flowing to the load connected to the auxiliary battery 40. That is, the first BC level V, which means the voltage V _E of the measured auxiliary battery that the battery remaining amount is sufficient
Compared 1 (step S10, shown only following step numbers.), If the battery voltage across V _E is greater than the first BC level V1 causes the full lighting the graphic display unit 602 of the liquid crystal panel 60 (S12) The user is notified that the remaining battery level is sufficient.

In S10, the voltage V _E across the battery becomes the first voltage.
Is smaller than the second BC level V1 which is the final voltage of the auxiliary battery 40 (S14). And the voltage V _E across the battery is the second
Is larger than the BC level V2 of the liquid crystal panel 6
The graphic display unit 602 of 0 is half-lit (S16),
The user is informed that the remaining amount is low, and the user is prompted to replace the battery.

In S14, when the voltage value V _E across the battery is less than the second BC level V2, the graphic display section 602 of the liquid crystal panel 60 is turned off (S18).
The user is notified that the energy of the auxiliary battery 40 has been completely consumed. FIG. 12 shows an example of a sequence of charging the main battery. When charging of the main battery 34 is permitted (S20), the battery check of the auxiliary battery 40 is performed as described with reference to FIG. 11 (S22), and after it is confirmed that the auxiliary battery is not exhausted, Charging of the battery 34 is started (S24).

During the charging period, it is monitored whether or not the camera operation has been performed (S26). If there is an input by any switch operation, for example, a release operation, the charging ends (S40). If there is no switch input in S26, charging is continued until the voltage of the main battery 34 reaches 3.25V (full charge state) (S26 to S32). Main battery 3
4 is less than 3.25 V, the charge amount increases in accordance with the elapsed time. Therefore, the shot counter is decremented in accordance with the elapsed time T (S30, S3).
2). By repeating S26 to S32, energy is stored in the main battery 34. Then, when the voltage of the main battery reaches 3.25 V, the process proceeds to S34, the shot counter is reset to 0 (S34), and the charging ends (S40).

FIG. 13 is a flowchart showing the flow of processing of the camera. Initial processing required by the camera system is performed by power-on reset when the auxiliary battery is loaded or by replacing the main battery (S50). The initial processing includes, for example, setting of initial values for clock display, starting charging of the main battery, and the like. When the main battery 34 is charged (S
52), as shown in FIG. 9, the camera waits for reception of a switch operation (S54, S56). Each time the reception standby time elapses the predetermined time interval t without the switch operation being performed (S56), the decimal part of the shot counter is incremented according to the predetermined energy ratio conversion value (S58), and the process returns to S54. .

When a switch input is detected in S54, the process proceeds to S60, and it is determined whether or not a release switch is input. The release button is pressed,
When the half-press operation (SP1 ON) is detected, a battery check of the main battery 34 is subsequently performed (S72). The battery check at this time may be performed based on the voltage between both ends of the main battery shown in FIG. 6, or may be performed based on the measurement of the charge / discharge amount of the main battery shown in FIG.

If it is determined in S72 that the electric capacity stored in the main battery 34 is insufficient, the release operation is locked to inhibit the release operation (S74), and the process proceeds to (A). Return. In S72, if it is determined that the electric capacity stored in the main battery 34 is sufficient, photometry and distance measurement are performed (S76, S78), and based on the results, the exposure value (AE value) and flashmatic (FM) operation is performed (S80). Subsequently, it is detected whether or not the release button has been fully pressed (S8).
2) If full depression is confirmed (SP2 ON), a focusing operation is performed to move the taking lens to the in-focus position (S84), and the shutter opens and closes (S86). Note that the strobe emits light while the shutter is open.

After the photographing, the film is wound up by one frame (S88), and the shot counter is incremented (S90). When a switch other than SP1 indicating a half-pressing operation of the release in S60, for example, a zoom switch is input, an operation corresponding to the operation such as driving the zoom motor and moving the zoom lens is executed (S62). ). Then, the amount of energy consumed according to the operation load is converted into an energy ratio for one shot, and is added to the decimal part of the shot counter (S6).
4). Similarly, if another setting switch is input in S60, the operation corresponding to each operation is performed (S66), and the amount of energy consumed according to each operation load is calculated as the energy ratio for one shot. And add it to the decimal part of the shot counter (S68).

As described above, by considering the energy consumption due to the operation of various switches other than the release operation as the decimal part of the shot counter, the discharge amount of the main battery can be accurately estimated. When the shot counter is incremented in S90, the total shot counter is also incremented (S9).
2). The total shot counter keeps counting the total number of shots for one main battery without being decremented as the main battery 34 is charged. The life of the main battery 34 is determined based on the value of the total shot counter.

Thereafter, flash charging is allowed (S9).
4). Subsequently, the count value of the shot counter is checked (S96). If the count value is not zero, the process returns to (A) and the main battery 34 is charged. On the other hand, S96
If the count value is zero, it means that the main battery 34 has sufficient energy stored so that it does not need to be charged. Therefore, the charging of the main battery is omitted, and the process returns to (B). Then, a switch input standby state (standby state) is set.

According to the camera of this embodiment, when the auxiliary battery 40 is exhausted, it is only necessary to replace the inexpensive auxiliary battery 40, and it is more economical and environmentally friendly than replacing the main battery 34. It has the advantage of being preferred. Further, there is an advantage that a large capacity and a large current can be supplied from the main battery 34 to the camera circuit, and the spontaneous discharge is small, so that photographing can be performed at any time without using for a long time.

The amount of charge is determined by measuring the charging current flowing into the main battery 34, and the amount of consumption is determined by measuring the discharge current discharged from the main battery 34.
Monitoring the incoming and outgoing energy, it is possible to display a warning or prohibit camera operation when the remaining amount of the main battery is low. In addition, the remaining amount of the main battery 34 can be similarly managed by the shot counter. Thus, the remaining amount of the main battery 34 can be prevented from falling below a predetermined electric capacity, and the performance of the main battery 34 can be maintained for a long period of time.

In the above embodiment, the case where the auxiliary battery and the charging circuit are incorporated in the camera together with the main battery has been described. However, the auxiliary battery and the charging circuit are separate charging devices separated from the camera. Can also.

[0081]

As described above, according to the camera of the present invention, power is supplied from the main battery to the camera, and the main battery is charged by an auxiliary battery such as an AA dry battery. When the auxiliary battery is exhausted, only the auxiliary battery which is inexpensive and easily available need be replaced, and there is an advantage that it is more economical and more environmentally friendly than replacing the main battery. In addition, since the main battery is charged even if the auxiliary battery is exhausted, there is an advantage that the camera can be used until the main battery is exhausted.

In particular, a metal lithium-based secondary battery is used as the main battery.
By using the secondary battery, a large capacity and a large current can be supplied from the main battery to the power consuming means, and since there is little spontaneous discharge, photographing can be performed at any time even when not used for a long time. In addition, since the charging current flowing into the main battery is measured by the charging amount measuring means, and the discharging current discharged from the main battery is measured by the discharging amount measuring means, the energy amount of the main battery is monitored. In addition, the remaining amount of the main battery can be prevented from falling below a predetermined electric capacity, and the performance of the main battery can be maintained for a long time.

Further, when the main battery reaches a fully charged state (a fully charged state), it is reset to zero, and the remaining amount of the main battery is monitored by a shot counter which is incremented in accordance with the photographing operation. Is also good. In this case, the remaining amount of the main battery can be grasped more accurately by considering the decimal part of the count value. The display means for indicating the remaining amount of the main battery and the display means for indicating the remaining amount of the auxiliary battery are provided separately and independently, so that the user can easily understand. In particular, when a liquid crystal display panel is used, a display area of the liquid crystal display panel is displayed by superimposing and displaying a second figure imitating the shape of the auxiliary battery inside the first figure imitating the shape of the main battery. Can be saved in space, and both display contents can be easily recognized.

[Brief description of the drawings]

FIG. 1 is a front internal perspective view of a camera to which the present invention is applied.

FIG. 2 is a top internal perspective view of a camera to which the present invention is applied.

FIG. 3 is a side internal perspective view of a camera to which the present invention is applied.

FIG. 4 is a block diagram including a charging circuit for charging a main battery with an auxiliary battery.

FIG. 5 is a circuit diagram illustrating an example of a booster circuit.

FIG. 6 is a block diagram illustrating a configuration of a control system of the camera.

FIG. 7 is a block diagram showing a configuration of a management unit for managing a charge amount and a discharge amount of a main battery.

FIG. 8 is a flowchart for explaining a series of operations for one shot associated with a release operation.

FIG. 9 is a plan view of the liquid crystal panel used for explaining an example of display contents of the liquid crystal panel.

FIGS. 10A and 10B are explanatory diagrams used to explain another display mode displayed on the liquid crystal panel. FIG. 10A is an explanatory diagram showing a display when the remaining amount of the auxiliary battery is sufficient. ,
(B) is an explanatory view showing a display after the auxiliary battery is exhausted.

FIG. 11 is a flowchart illustrating a flow of a battery check process of an auxiliary battery.

FIG. 12 is a flowchart showing an example of a main battery charging sequence.

FIG. 13 is a flowchart showing the flow of processing of the camera.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Camera 14 ... Cartridge chamber 16 ... Film take-up chamber 18 ... Strobe device 28 ... Take-up spool 30 ... Film feeding motor 34 ... Main battery 40 ... Auxiliary battery 43 ... Control circuit mounting space 44 ... Step-up circuit mounting space 50 ... Charging circuit 52 ... Charge control circuit 54 ... Boost circuit 60 ... Liquid crystal panel (LCD) 70 ... Central processing unit (CPU) 72 ... Shutter circuit 74 ... Strobe circuit 76 ... Film feeding circuit 78 ... EEPROM 92,96 ... Dynamic amplifiers 602, 604: Graphic display unit 620: First figure showing main battery 630 ... Second figure showing auxiliary battery

Continued on the front page (72) Inventor Miyoshi Takahashi 1-324 Uetake-cho, Omiya-shi, Saitama Prefecture Inside Fuji Photo Optical Co., Ltd. (72) Inventor Shigenori Goto 1-324 Uetake-cho, Omiya-shi, Saitama Fuji Fuji Photo Light Machine Co., Ltd.

Claims (13)

[Claims] An electric power is supplied from a main battery which is substantially equal to a self-discharge rate of a primary battery and which can be repeatedly discharged and charged when a remaining amount is equal to or more than a predetermined capacity, to a plurality of power consuming means necessary for a photographing operation. And a booster for boosting an output voltage of the auxiliary battery, and supplying power to the main battery via the booster. A charging means for charging the battery; a charging current measuring means for measuring a charging current supplied from the auxiliary battery to the main battery via the boosting means to obtain a charging electric charge supplied to the main battery; A discharge amount measuring unit that measures an emission current supplied from the main battery to the power consuming unit and obtains a discharge charge amount discharged from the main battery; and a charge amount and the discharge amount obtained by the charge amount measurement unit. Determined by measuring means Comparing the discharge charge quantity, characterized in that the remaining amount of the main battery is and a discharge amount monitoring means for monitoring so as not to fall below the predetermined capacity camera. 2. The discharge amount monitoring means calculates a difference between the charge amount obtained by the charge amount measurement means and the discharge charge amount obtained by the discharge amount measurement means, and the difference is smaller than a predetermined reference value. 2. The camera according to claim 1, wherein when the power consumption is small, the operation of the power consumption unit is prohibited so that the power consumption unit does not consume power. 3. Power is supplied from a main battery that is substantially equal to the self-discharge rate of the primary battery and that can be repeatedly discharged and charged when the remaining amount is equal to or more than a predetermined capacity, to a plurality of power consuming means necessary for a photographing operation. And a booster for boosting an output voltage of the auxiliary battery, and supplying power to the main battery via the booster. Charging means for charging the battery, and a series of photographing operations associated with the release operation are defined as one shot,
A shot counter for adding and counting the number of shots for each release operation, and resetting means for resetting the count value of the shot counter to zero when the main battery reaches a fully charged state by the charging means. A discharge amount monitoring unit that monitors the remaining amount of the main battery based on a count value of the shot counter so that the remaining amount does not fall below the predetermined capacity. 4. The discharge amount monitoring means displays a warning on a display means when detecting that the count value of the shot counter exceeds a predetermined first boundary value. Item 3. The camera according to Item 3. 5. The discharge amount monitoring means, when detecting that the count value of the shot counter has exceeded a predetermined second boundary value, so that the power consuming means does not consume power. 4. The camera according to claim 3, wherein the operation of the power consuming means is prohibited. 6. The count value of the shot counter is provided with a decimal part less than one shot, and when at least one of a series of shooting operations constituting one shot is performed, the operation is performed by the operation. 4. The camera according to claim 3, wherein the amount of energy consumed by the power consuming means is converted into an energy ratio for one shot, and the converted energy ratio is added to a decimal part of the shot counter in accordance with the operation content. . 7. The count value of the shot counter is provided with a fractional part of less than one shot, and the amount of energy consumed for maintaining the main battery spontaneous discharge or the camera standby state is measured with time. 4. The camera according to claim 3, further comprising converting the energy ratio into one shot, and adding the energy ratio converted according to the non-operation time of the camera to a decimal part of the shot counter. 8. A decrement means for supplying energy to the main battery from the auxiliary battery via the boosting means and decreasing the count value of the shot counter as the energy stored in the main battery increases. 4. The camera according to claim 3, further comprising: 9. A series of photographing operations accompanying a release operation is performed by one
A shot, a total shot counter that counts by adding the number of shots for each release operation, and when detecting that the count value of the total shot counter has reached a predetermined limit value, replacing the main battery. The camera according to claim 1, further comprising: a warning unit configured to display a warning prompting the user on a display unit. 10. A first display means for displaying the remaining amount or replacement time of the main battery and a second display means for displaying the remaining amount of energy or replacement time of the auxiliary battery are provided separately and independently. The camera according to claim 1, wherein the camera is provided. 11. A liquid crystal display panel for displaying the remaining amount or replacement time of the main battery and displaying the remaining amount or replacement time of the auxiliary battery, wherein the liquid crystal display panel has a shape of the main battery. A second figure imitating the shape of the auxiliary battery is superimposed and displayed inside the first figure imitated, the remaining amount of the main battery is displayed by the first figure, and the auxiliary battery is displayed by the second figure. The camera according to claim 1, wherein the camera is configured to display a remaining amount of the camera. 12. The camera according to claim 1, wherein the main battery is a metal lithium secondary battery. 13. The camera according to claim 1, wherein the auxiliary battery is a manganese-based primary battery.