JP4027104B2 - Digital camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera such as a digital still camera or a digital video camera having a secondary battery as a power source, and a charger for the digital camera.
[0002]
[Prior art]
A configuration example of a conventional digital still camera is shown in FIG. In FIG. 6, reference numeral 10 denotes an imaging lens, and 11 denotes a CCD (charge coupled device: charge coupled device) as an imaging element. The subject image is formed on the imaging surface of the CCD 11 through the imaging lens 10. The CCD 11 can photoelectrically convert the subject image formed on the imaging surface to obtain an imaging signal, and this imaging signal is sent to the CDS / A / D 12. Here, CDS is correlated double sampling, and CDS / A / D is an integrated CDS_IC and analog / digital conversion IC. The vertical driver 13 and the timing generator 14 are necessary for driving the CCD 11 and are constituted by an IC. The image pickup signal sent to the CDS / A / D 12 is sequentially converted into digital 10-bit data by the A / D conversion unit while performing correlated double sampling in the CDS unit, and is supplied to a DSP (digital signal processor) 15. Sent. Here, the A / D conversion is 10 bits as an example, but an A / D converter having a multi-bit output may be used.
[0003]
The digital data sent to the DSP 15 is subjected to interpolation processing, edge enhancement processing, AWB (Auto White Balance) processing, RGB-YUV conversion, etc., and then sent to the SDRAM 19. The RGB-YUV conversion is to convert R (red), G (green), and B (blue) data into a luminance component Y and color difference components U and V.
At the time of monitoring, the data in the SDRAM 19 is sent to the DSP 15 again, converted into a predetermined format by the video encoder, and then output as an image from the D / A conversion output unit to the display LCD (liquid crystal display), the television 18 or the like. .
[0004]
At the time of recording, in order to compress the imaging signal, the scale factor is calculated by the main CPU 20 connected to the DSP 15, compressed by the JPEG unit in the DSP 15, sent to the card memory 17 and recorded.
The sub CPU 23 connected to the main CPU 20 mainly controls an interface with the user. A real-time clock IC (hereinafter referred to as “RTC”) 25 connected to the sub CPU 23 manages time information, and since it consumes less current than the sub CPU 23, it is generally used.
[0005]
These ICs are supplied with a voltage from the main battery 28 through the DC / DC module 27 and converted into a necessary voltage value. However, the RTC 25 often has a dedicated sub battery 29. This is because it is necessary to retain time information for a certain period even when the power of the main battery 28 is exhausted or when the main battery 28 is removed.
The above is an example of a configuration of a conventional digital still camera and a signal flow.
[0006]
[Problems to be solved by the invention]
In a conventional digital still camera, it is necessary to first set date / time information before use after purchase.
This is necessary work for managing when and which photograph was taken, and is an important work necessary for use in business use or when photographing a child's growth record or the like. However, this date / time setting work is complicated and forces the user to perform troublesome work.
Most digital still cameras use a battery as an operating power source. However, since the digital still camera consumes a large amount of power, the life of the battery is often reached in a relatively short time. If the capacity of the battery (hereinafter referred to as “main battery”) is exhausted, the set date / time information will also be lost, and when the main battery is replaced at the next shooting opportunity, the above-mentioned troublesome date setting work is performed again. Was supposed to be forced.
[0007]
In order to avoid such a situation as much as possible, a circuit capable of holding the date / time information once set even after the main battery is exhausted is provided inside the digital still camera body.
As a method often used, there is a method in which an RTC and an auxiliary battery for RTC operation (hereinafter referred to as “sub-battery”) are provided inside the digital still camera.
The RTC is a digital IC device that has a time counting function, and once the date and time are set, a predetermined signal is input after the setting to output the current date / time information.
[0008]
As a sub-battery serving as a power source for the RTC, a secondary battery such as a Li battery or a Ni-Cd battery, a large-capacity capacitor called a gold capacitor, a supercapacitor, or a Li primary battery is used.
However, these sub-batteries have a proportional relationship between capacity and size, and digital still cameras that are required to be small to some extent cannot have such a large sub-battery. Therefore, in recent years, it is almost impossible to use a Li primary battery having a large outer shape as a sub-battery.
Eventually, there is a situation where the sub-battery cannot be made large as described above. Therefore, even if an attempt is made to maintain date / time information for a long period of time as much as possible using the RTC, the sub-battery is completely discharged after a few months. There is a reality that date / time information is reset.
[0009]
On the other hand, in recent years, as a main battery of a digital still camera, there are an increasing number of models using a Li ion secondary battery. The main reason is that the power consumption of the digital still camera is so great that it is uneconomical to use a primary battery that must be discarded every time the power is consumed. Since the main battery is the above-described Li ion secondary battery, a dedicated charger is often attached to the digital still camera. FIG. 7 shows a conventional example of a digital still camera having a dedicated charger. In the conventional example shown in FIG. 7, the main battery 28 of the camera body 50 can be charged by inserting it into the charger 40 while the main battery 28 is loaded in the camera body 50. From the image of how to use the charger 40, the charger 40 may be called a cradle as described above.
[0010]
In the conventional example shown in FIG. 7, the interface connector with the personal computer 22 is also arranged on the charger 40 side. The charger 40 is an AC / DC module 31 that converts AC power to DC, and charging that converts the converted DC power voltage into a predetermined voltage and supplies it to the main battery 28 on the camera body 50 side to charge the main battery 28. A circuit 30 is included. Since other configurations are the same as those of the conventional example shown in FIG. 6, common components are denoted by common reference numerals, and description thereof is omitted.
[0011]
According to the conventional example shown in FIG. 7, it is not necessary to bring the charger 40 to the shooting location, so that it can be easily imagined that the charger 40 is used beside the personal computer 22. Therefore, it is more effective to reduce the size of the camera body 50 when a large-sized digital still camera component such as an interface connector with the personal computer 22 is arranged on the charger 40 side.
In the example shown in FIG. 7, only the interface / connector portion with the personal computer 22 is arranged on the charger 40 side, but it may be arranged on the charger 40 side including functional parts such as an RS232C driver and a USB controller. it can. However, in order to connect the camera body 50 to the personal computer 22, the charger 40 is always required. In addition to the interface connector with the personal computer 22, there is a conventional example in which an interface portion with a television is arranged on the charger 40 side.
[0012]
As described above, as a function of the cradle-shaped charger 40, when the camera body 50 is inserted into the charger 40 for purposes other than the purpose of charging the main battery in the digital still camera body 50, it automatically enters the personal computer 22. It has been considered to provide a function of sucking up image data, or a function of sending image data to the television 18 to display an image.
[0013]
Alternatively, as described in Japanese Patent Application Laid-Open No. 2000-333046, when the cradle has an image display function and the digital still camera body is inserted into the cradle, the recorded image data is sucked from the camera body, and the images are displayed in a slide show format. There are also proposals that have special functions such as displaying with.
However, according to the conventional cradle or digital camera charger used in combination with the digital camera body, functions other than the main battery charging function in the digital camera body are limited to the functions described above. It has no useful function.
[0014]
The present invention has been made in view of the prior art as described above, and is a digital camera that can be connected to a charger for charging a secondary battery as a power source while the secondary battery is loaded. An object of the present invention is to provide a digital camera that can greatly reduce the number of troublesome date / time settings compared to the conventional method and can reduce the size of the camera body.
It is another object of the present invention to provide a digital camera charger that can significantly reduce the number of troublesome date / time settings in a digital camera as compared to the conventional technique and can reduce the size of the digital camera body. .
[0015]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a CPU which operates using a frequency multiplied by a clock cycle as a source oscillation and can generate an interrupt signal in units of one second by an internal timer, and a secondary battery as a power source. In a digital camera having a charger that can be connected to be charged while being loaded, the charger includes a real-time clock IC, a timepiece vibrator, a small secondary battery that backs up the operation of the real-time clock IC, and a digital It has a communication unit with the camera body, and when the time of the real-time clock IC is set, the value set by operating the switch of the digital camera body is transmitted from the communication unit to the real-time clock IC, digital camera body, when a display unit to display based on the signal transmitted from the charger Moni, when the digital camera body for secondary battery charging is to update the time by real-time clock IC charger side when plugged into the charger, the digital camera body is removed from the charger, the two- the following battery as a power source, characterized in that it is configured to update the time by the CPU incorporated in the digital camera body.
[0016]
According to a second aspect of the invention, in the invention according to the first aspect, the charger, the communication function of the personal computer in addition to the communication function between the digital camera and the personal computer also has, the time setting of the real-time clock IC, It is configured so that it can be performed from the personal computer side.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a digital camera and a digital camera charger according to the present invention will be described with reference to the drawings. The same components as those of the conventional example shown in FIGS. 6 and 7 are denoted by the same reference numerals, and components different from those of the conventional example will be described mainly.
[0022]
FIG. 1 shows an embodiment of a digital camera according to the present invention. In FIG. 1, the RTC 25, the sub-battery 29, the sub-battery charging circuit 30 and the watch ceramic oscillator 26, which are conventionally arranged on the digital still camera main body 50 side, are arranged on the side of the charger 40 configured like a cradle. Is arranged. On the digital camera main body 50 side, an insertion / extraction detection means 35 for detecting that the camera main body 50 has been inserted into the charger 40 and removed from the charger 40 is added.
[0023]
Providing a dedicated interface for setting the current time to the RTC 25 on the charger 40 side is also effective in improving user convenience. However, since the battery charger 40 may increase in cost or become large in size, the embodiment shown in FIG. 1 uses the user interface switch on the digital camera main body 50 side, and the camera main body. It is assumed that the time setting of the RTC 25 on the charger 40 side is performed via the sub CPU 23 on the 50 side. The sub CPU 23 operates using the frequency multiplied by the clock period as a source oscillation, and generates an interrupt signal in units of one second with an internal timer. The clock oscillator 26 generates a signal having a frequency that is the basis of the multiplied frequency.
[0024]
A flowchart of the time setting process is shown in FIGS. Symbols such as S1, S2,... Indicate operation steps. In FIG. 3, the time setting process starts with the setting of the year (S1), the setting of “month” (S2), the setting of “day” (S3), the setting of “hour” (S4), and the setting of “minute” ( The process proceeds to S5) and “second” setting (S6) in this order. Next, the sub CPU 23 starts time count-up (S7), and performs time setting processing (S8) to the RTC 25 on the charger 40 side. The time setting process for the RTC 25 is shown in FIG. The time setting process to the RTC 25 determines whether or not the camera body is inserted into the cradle (charger 40) (S11), and if it is not inserted, "Please insert the camera body into the cradle" A message prompting the user to insert the main body 50 into the charger 40 is displayed (S14). When the camera body 50 is plugged into the charger 40, the current time is transmitted to the RTC 25 on the charger 40 side, "Time setting complete" is displayed, and the time setting process to the RTC 25 is finished.
[0025]
In addition to the time setting process for the RTC 25 as described above, a communication function is provided between the charger 40, the camera body 50, and the personal computer 22, and the time is set by application software of the personal computer 22. Is also an effective means. In the embodiment shown in FIG. 1, since the charger 40 has an interface part with the personal computer 22, predetermined data is input from the keyboard of the personal computer 22, and time information is transmitted via the main CPU 20 of the camera body 50. A method of transmitting to the sub CPU 23 and the RTC 26 is preferable. This not only improves the user-friendliness, but also eliminates the need for the user interface / switches arranged in the camera body 50 to be multi-function, thus making complicated software processing unnecessary.
Of course, the time information may be obtained from the DOS information of the personal computer 22. That way, no application software is needed.
[0026]
Next, once the time information is set in the RTC 25, the camera body 50 is removed, and shooting and other operations are performed. After the main battery 28 of the camera body 50 is exhausted, it is inserted into the charger 40 again for charging. The processing when this occurs is described.
When the camera body 50 is inserted into the charger 40, a DC power supply for charging is supplied from the AC power source to the main battery 28 on the camera body 50 side via the AC / DC module 31 and the charging circuit 30 of the charger 40. The Then, the sub CPU 23 can detect that the camera body 50 is inserted into the charger 40 at that time by the detection operation of the insertion / extraction detection means 35.
[0027]
When it is detected that the camera body 50 is inserted into the charger 40, update processing of time information from the RTC 25 of the charger 40 to the sub CPU 23 on the camera body 50 side is started. FIG. 5 shows the flow of the processing. In FIG. 5, it is determined whether or not the camera body 50 is inserted into the charger 40 (S21). If it is not inserted, the operation ends. If it is inserted, the camera body 50 side starts from the RTC 25 of the charger 40. The current time information is received (S22), and the operation ends.
Although this time information update process does not appear to be a problem even if it is performed once, it is preferable to repeat the update process at intervals of several seconds while the camera body 50 is inserted into the charger 40. Thereby, the accuracy and reliability of time information can be improved.
[0028]
As described above, in the embodiment shown in the figure, it is not necessary to arrange the RTC 25, the clock oscillator 26, the AC / DC module 31, the sub battery 29, etc. on the digital still camera body 50 side. It becomes possible to dramatically reduce the size of the still camera body 50. In addition to this, the charger 40 has a longer time for being connected to the AC power source than the time for which the camera body 50 is plugged into the charger 40 due to its characteristics. It is unlikely that the capacity will be lost, and the number of annoying date / time settings can be greatly reduced as compared with the prior art.
[0029]
FIG. 2 shows a modification of the embodiment shown in FIG. In the embodiment shown in FIG. 2, a radio timepiece is used as a time acquisition means instead of the RTC so as to obtain a more accurate time, and a GPS function is also provided. When the digital still camera device including the digital still camera and the charger is taken overseas, for example, the standard time of the country can be automatically set.
In FIG. 2, the charger 40 has connection terminals for the charging circuit 30, the AC / DC module 31, and the personal computer 22 in the same manner as the charger 40 in the embodiment shown in FIG. In place of the RTC 26 and the clock vibrator 26 in the embodiment, the radio clock unit receiver 37, the reception antenna 47, the GPS 38, and the reception antenna 48 are provided, and the radio clock unit receiver 37 and the GPS 38 The CPU 36 controls the operation and inputs each received data to the sub CPU 23 on the camera body 50 side. The receiving antenna 48 and the receiver 37 of the radio clock unit constitute standard radio wave receiving means.
[0030]
The time count method in the RTC 25 and the sub CPU 23 is the same as the time count method in the quartz timepiece. While an ordinary quartz clock generates an error of 15 to 20 seconds per month, the receiver 37 of the radio clock unit receives time data based on an atomic clock and displays the clock, so the error is 30. It has a high accuracy of less than 1 second per million years. Therefore, each time the camera body 50 is inserted into the charger 40, the CPU 36 in the charger 40 sends accurate time information of the radio clock to the sub CPU 23 of the camera body 50, thereby updating the time information. Thus, highly reliable time information can be obtained, and highly accurate and reliable time display can be performed.
[0031]
Here, consider a case where only the receiver 37 of the radio clock unit is incorporated. The receiver 37 of the radio clock part is currently limited to countries where radio waves are being transmitted overseas, such as the United States, the United Kingdom, and Germany, and the transmission frequency of standard time radio waves varies from country to country. There are problems such as. The contents of the transmission code (time code) are also different. That is, while Japan and the United States have time information at that moment, the United Kingdom and Germany have the next minute information. Therefore, in order to determine the country in which the radio clock 37 is located, an operation such as sweeping the reception frequency is required. In addition, even if you have such means, you may not be able to receive in all countries.
[0032]
Therefore, in the embodiment shown in FIG. 2, the GPS 38 is first used to acquire geographical information where the user is placed, and the CPU 36 corrects the deviation from the existing time information based on the result. With this configuration, there is an advantage that the time can be adjusted even in a country that does not have a standard radio wave transmission station.
[0033]
In the case of the embodiment shown in FIG. 2, the user sets the time in the sub CPU 23 using the user interface switch of the personal computer or the camera body as in the embodiment shown in FIG. A troublesome process of setting the time in the RTC 25 on the charger 40 side is also unnecessary.
[0034]
In the digital camera charger 40, the standard time may be acquired by the standard radio wave receiving means, and the video output method may be automatically set from the charger 40 side to the digital camera body 50 side. When you go abroad and check the captured data on the TV 18, you can automatically change the video output method from the charger 40 side to the digital camera body 40 side if necessary, It becomes possible to dispense with troublesome setting change work on the camera body 40.
[0035]
In the digital camera charger 40, the standard time may be acquired by the standard radio wave receiving means, and the OSD display language may be automatically set from the charger 40 side to the digital camera body 50 side. The OSD is an abbreviation of “On Screen Display”, and the OSD display language is a language used to display characters (characters) on a screen such as a television or a liquid crystal display. By having the standard radio wave receiving means and the GPS device in the charger 40, the OSD display language is automatically switched to the shipping destination language even if the country where the camera body 50 is manufactured differs from the shipping destination. This makes it possible to dispense with troublesome setting change work on the camera body.
[0036]
The present invention is applicable to both a still camera and a movie camera as long as it is a digital camera.
[0037]
【The invention's effect】
In the digital camera according to claim 1, that the RTC circuit built in the main body of the conventional digital camera, arranged like the charger-side sub-battery, which have a communication unit of the digital camera body, the camera body The size and weight can be reduced, and even when the main battery of the camera body is used up, the opportunity to reset the time can be greatly reduced.
[0038]
In the digital camera according to claim 2, since the time information held by the digital camera can be rewritten from a personal computer, the usability is greatly improved as compared with the case where the time is set on the camera body. The processing of the sub CPU built in the main body can also be simplified.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram showing an embodiment of a digital camera and a digital camera charger according to the present invention.
FIG. 2 is a circuit block diagram showing another embodiment of a digital camera and a digital camera charger according to the present invention.
FIG. 3 is a flowchart showing a time setting processing procedure in the embodiment.
FIG. 4 is a flowchart showing a time setting processing procedure for an RTC in the embodiment.
FIG. 5 is a flowchart showing a time information update processing procedure from the RTC to the sub CPU in the embodiment.
FIG. 6 is a circuit block diagram illustrating an example of a conventional digital camera.
FIG. 7 is a circuit block diagram showing another example of a conventional digital camera and a digital camera charger.
[Explanation of symbols]
22 PC 23 CPU
25 Real-time clock IC
26 Clock oscillator 28 Secondary battery power supply 29 Small secondary battery 36 CPU
37 Radio clock receiver 38 GPS

Claims (2)

Built-in CPU that operates with a frequency multiplied by the clock cycle and can generate an interrupt signal in units of 1 second with an internal timer, and uses a secondary battery as a power source to charge the battery while it is loaded In a digital camera with a charger that can be connected,
The charger has a real-time clock IC, a timepiece vibrator, a small secondary battery that backs up the operation of the real-time clock IC, and a communication unit with the digital camera main body. When setting the time of the real-time clock IC, the charger A value set by operating a switch of the digital camera body is configured to be transmitted from the communication unit to the real-time clock IC.
The digital camera body has a display unit that displays based on the signal transmitted from the charger. When the digital camera body is inserted into the charger for charging the secondary battery, the digital camera body uses a real-time clock IC on the charger side. the update of the time, when the digital camera is removed from the charger that is configured to the secondary battery as a power source, the update of the time by the CPU incorporated in the digital camera body A featured digital camera. In claim 1 a digital camera according, charger, in addition to the communication function with the digital camera main body and have also a communication function with the PC, the time setting of the real-time clock IC, so that it can be performed from the personal computer A digital camera characterized by being configured.

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