JPH0556321A - Recorder - Google Patents

Abstract

PURPOSE:To reduce a power consumption by carefully controlling a power supply to each part. CONSTITUTION:The power supply to an image pickup element 16, A/D converter 18, digital signal processing circuit DSP 20, and synchronizing signal generating circuit SSG 28, is operated by the turn-on of a switch 38, so that a light measurement and a color measurement can be operated. The power supply to a buffer memory 22 is operated by the turn-on of a switch 40, an exposure is operated to the image pickup element 16, the charge signal of the image pickup element 16 is processed and written in the buffer memory 22, and the power supply to the image pickup element 16 and the A/D converter is interrupted. Then, the power supply to an interface I/F 26 and a memory device 24 is operated, and the data of the buffer memory 22 are transferred to the memory device 24. After the completion of the transfer, the power supply to the DSP 20, buffer memory 22, and SSG 28 is interrupted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device, and more particularly to a recording device for recording a still image on a recording medium.

[0002]

2. Description of the Related Art In a conventional electronic still camera, before recording a captured image on a magnetic disk or a semiconductor memory (memory card) which is a final recording medium, an intermediate storage device (image memory, buffer memory, etc.) ) Has been proposed to store once.

For example, in the first stroke of the release operation, power is supplied to the image pickup device and the buffer memory for signal processing, the magnetic disk which is the final recording medium is activated, and the second stroke (and the magnetic field of the release operation). The image taken by the image sensor is recorded on the magnetic disk via the buffer memory according to the stability of the rotation of the disk.

Further, the picked-up image is temporarily stored in an intermediate storage device (frame memory), the magnetic disk is activated at an appropriate stage thereafter, and the image stored in the intermediate storage device is transferred to and recorded on the magnetic disk. The configuration is Japanese Patent Laid-Open No. 64-1
No. 6081. According to this configuration, it is possible to select whether or not recording on the magnetic disk can be performed after shooting, and the start-up speed of the rotation of the magnetic disk can be relatively slowed, so that there is an advantage that peak power consumption can be reduced.

Further, a configuration in which an image stored in an intermediate storage medium is output on a monitor so that whether or not to record the image on the final recording medium can be determined by looking at the monitor image is disclosed in, for example, Japanese Patent Laid-Open No. 10-1079. No. With this configuration, the magnetic disk is activated according to a user's instruction to record the image stored in the intermediate storage medium on the magnetic disk that is the final recording medium. This reduces the power consumption due to the startup and rotation of the magnetic disk.

[0006]

In the first conventional example described above, a large amount of power is temporarily consumed by the simultaneous power supply to the drive system of the buffer memory and the magnetic disk. There is a drawback that the load on the battery is heavy and the battery life is short.

In the second and third conventional examples, it is possible to reduce the peak power consumption during photographing. But not enough.
Further, in the third conventional example, the user's operation is required for the transfer from the intermediate storage medium to the final recording medium, which deteriorates the operability during continuous shooting.

It is an object of the present invention to provide a recording device that solves these problems.

[0009]

A recording apparatus according to the present invention comprises an image pickup means for converting a subject image into an electric signal, a temporary storage means for temporarily storing imaged image information by the image pickup means, and a read from the temporary storage means. Recording means for recording and holding the issued image information, trigger generating means for generating a recording trigger signal, power supply means for supplying necessary power to the imaging means, the temporary storage means and the recording means,
In response to the trigger signal from the trigger generating means, power is supplied to the image pickup means and the temporary storage means, the image information to be recorded is written in the temporary storage means, and after the writing in the temporary storage means is started, the image is recorded in the recording means. It is characterized by comprising control means for controlling the image pickup means, the temporary storage means, the recording means and the power supply means so as to transfer power and transfer image information from the temporary storage means to the recording means. To do.

[0010]

By the above means, the power supply to each part is finely controlled. As a result, the instantaneous value of power consumption can be kept small.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic block diagram of an embodiment of the present invention. Reference numeral 10 is a taking lens, 12 is an aperture, 14 is an aperture drive circuit for opening and closing the aperture 12, 16 is an image sensor, and 1
Reference numeral 8 is A for converting the output of the image pickup device 16 into a digital signal.
The / D converter 20 is a digital signal processing circuit (DSP) that performs signal processing such as photometry, color measurement, and compression using the buffer memory 22.

Reference numeral 24 is a large-capacity memory device for finally storing the photographed image, for example, a magnetic disk drive device, an optical disk drive device, a magneto-optical disk drive device, and an EEPROM or a battery-backed DRA.
A solid-state memory device including M and the like. A so-called memory card corresponds to the solid-state memory device. 26
Is an interface between the output of the DSP 20 and the memory device 24.

Reference numeral 28 is a synchronization signal generation circuit (SSG) for supplying the necessary clock and synchronization signals to the image pickup device 16, the A / D converter and the DSP 20, 30 is a system control circuit for controlling the whole, and 32 is a system control circuit. Power supply battery, 34 power switch, 36 under the command of the system control circuit 30, circuit 1
4 is a power supply control circuit for controlling power supply to 28.

Reference numeral 38 denotes a switch which is closed by the first stroke of the shutter release button when the shutter release button is pressed, and 40 is a switch which is closed by the second stroke when the shutter release button is further pressed. Normally, the system control circuit 30 responds to the closing of the switch 38 by
Start preparations (photometry, color measurement, etc.) for shooting, and switch 4
Imaging (that is, exposure and reading of the image sensor 16) is performed in response to the closing of 0.

The operation of FIG. 1 will be described with reference to the flowcharts shown in FIGS. 2, 3 and 4.

When the power switch 34 is turned on, the system control circuit 30 is supplied with power and starts to operate. First, the inside is initialized (S1), and the condition of the external interrupt due to the closing of the switch 38 is set (S2). The interrupt is enabled (S3), and the standby state (sleep mode) is entered. The sleep mode is a low power consumption mode in which the contents of registers and the like in the system control circuit 30 are held but the counting operation of the counter and the program operation are stopped. Therefore, in this sleep mode, the battery 32 is hardly consumed even if the power switch 34 is closed.

When the switch 38 is first turned on by pressing down the shutter release button, the system control circuit 30 starts the program shown in FIG. 3 by an external interrupt. That is, first, the external interrupt is prohibited (S10), and the switch 38 is confirmed (S11). If the switch 38 is off (S11), the external interrupt is enabled (S18) to enter the sleep mode, and if the switch 38 is on (S11), the power supply control circuit 3
6, the image sensor 16, the A / D converter 18, the DSP 20
Then, power is supplied to the synchronizing signal generating circuit 28 (S12), and these are operated in the photometric mode (S13) and the colorimetric mode (S14).

In the photometric mode, for example, the diaphragm 12 is fully opened, the image pickup device 16 is exposed for a predetermined time, and the photoelectrically converted signal is read out. The A / D converter 18 digitizes the output of the image sensor 16, and the DSP 18 calculates the subject brightness by weighting and integration. In the color measurement mode, the color temperature of the subject illumination light is estimated from the subject brightness calculated in the photometry mode. The estimated color temperature adjusts the white balance.

Until the switch 40 is turned on (S1
6), photometry (S13) and color measurement (S14) are repeated,
In the meantime, if the switch 38 is turned off (S38), the power supply control circuit 36 causes the image sensor 16 and the A / D converter 1 to operate.
8, the power supply to the DSP 20 and the synchronization signal generating circuit 28 is cut off (S17), and the external interrupt is enabled (S18),
Enter sleep mode.

When the switch 40 is turned on by the second stroke of the shutter release (S16), the diaphragm 12 is controlled via the diaphragm drive circuit 14 according to the subject brightness calculated in the photometric mode (S13) (S19). , Power is supplied to the buffer memory 22 (S20), and the image sensor 16
Is exposed for a predetermined period after removing unnecessary charges (S2
1). The charge signal resulting from the exposure of the image sensor 16 is read out, converted into a digital signal by the A / D converter 18, and applied to the DSP 20 (S22).

The DSP 20 performs gamma correction and knee correction, adjusts the white balance according to the color temperature in the color measurement mode, compresses by a predetermined compression method, and writes the processed digital data in the buffer memory 22. .. Before writing to the buffer memory 22,
It is preferable to clear the contents of the buffer memory 22. This is because in the case of compression by the variable length coding method,
This is because the image data captured last time may remain in the buffer memory 22, and random initial data may be stored when the power is turned on.

Thereafter, the power supply control circuit 36 cuts off the power supply to the image pickup device 16 and the A / D converter 18 (S2).
3), power is supplied to the interface 26 and the memory device 24 (S24). The data stored in the buffer memory 22 is read out, and the DSP 20 and the interface 26 are read.
To the memory device 24 for recording (S2
5). After recording in the memory device 24, the power supply to the interface 26 and the memory device 24 is cut off (S25), and D
The power supply to the SP 20, the buffer memory 22 and the synchronization signal generation circuit 28 is cut off (S27).

When the switch 40 is turned off (S2
8), the switch 38 is checked (S29), and if it is off,
Enable external interrupts and enter sleep mode (S1
8) If it is on, the photometry and color measurement after S12 are continued. By S28 and S29, one frame image is recorded in the memory device 24 by one release operation, and photometry and color measurement are continued when the release button is half pressed.

As can be seen from the above description, the memory device 24 of this embodiment uses the electric power of the battery 32 for the recording operation of the image information, but does not use the battery 32 for holding the recorded information.

In the above-described embodiment, the compression information is stored in the buffer memory 22, so that the storage capacity required for the buffer memory 22 can be reduced. On the other hand, when the gamma-corrected, knee-corrected, and white-balance-adjusted image information is stored in the buffer memory 22 and is transferred to or from the buffer memory 22, the DSP 20 You may make it compress with a predetermined compression method.

The operation after the switch 40 is turned on may be changed as shown in the flowchart of FIG. FIG. 5 will be described. When the switch 40 is turned on (S
16) According to the subject brightness calculated in the photometric mode (S13), the diaphragm 12 is controlled via the diaphragm drive circuit 14 (S30), unnecessary charges are removed from the image sensor 16, and then exposure is started (S31). ). Power is supplied to the buffer memory 22 in consideration of the rise of the power supply voltage of the buffer memory 22 so that the buffer memory 22 is in a normal operating state at the time of completion of exposure (32).

In this way, the power supply time to the buffer memory 22 is minimized by starting power supply to the buffer memory 22 so that the buffer memory 22 will be in a normal operating state when the exposure of the image pickup device 16 is completed. it can.

After the exposure for a predetermined time is completed, the charge signal due to the exposure of the image pickup device 16 is read out, and the writing to the buffer memory 22 is started via the A / D converter 18 and the DSP 20 (S33). The DSP 20 performs gamma correction and knee correction, adjusts the white balance according to the color temperature in the color measurement mode, compresses the white balance by a predetermined compression method, and writes the processed digital data in the buffer memory 22. Note that, as in the case of FIG. 4, before writing to the buffer memory 22, the buffer memory 22
It is better to clear the contents of.

In response to the start of writing to the buffer memory 22, power is supplied to the interface 26 and the memory device 24 (S34), and the buffer memory 22 causes the memory device 2 to operate.
The transfer to 4 is started (S35). That is, the data stored in the buffer memory 22 is sequentially read out, and the DSP 2
0 and the interface 26 to the memory device 24 for recording and recording (S35).

When the writing to the buffer memory 22 is completed (S36), the image sensor 16 and the A / D converter 18
When the transfer from the buffer memory 22 to the memory device 24 is completed (S38), the power supply to the
P20, buffer memory 22, and sync signal generation circuit 2
The power supply to 8 is cut off (S39).

Thereafter, similar to S28 and 29 in FIG. 4, when the switch 40 is turned off (S40), the switch 38 is checked (S41). If the switch 38 is off, the external interrupt is permitted and the sleep state is set. (S18), and if on, the photometry and color measurement after S12 are continued.

In order to perform the operation shown in FIG. 5, the buffer memory 22 performs writing and reading simultaneously, but a dual port RAM may be used, for example. Further, the DSP 22 may have a circuit configuration that simultaneously performs a process for writing to the buffer memory 22 and a process for transferring the data read from the buffer memory 22 to the memory device 24. Of course, when the image is compressed during the transfer from the buffer memory 22 to the memory device 24, the data read from the buffer memory 22 is compressed and transferred to the memory device 24.

Since the memory device 24 usually has a low access speed, one frame of image is recorded in the memory device 24 by simultaneously writing to the buffer memory 22 and transferring from the buffer memory 22 to the memory device 24. The time required for can be shortened.

FIG. 6 is a block diagram showing the construction of another embodiment of the present invention in which the continuous shooting speed is increased. The same components as those in FIG. 1 are designated by the same reference numerals. Reference numeral 42 is a DSP that accesses the two buffer memories 44 and 46 and performs digital signal processing such as photometry, colorimetry, gamma correction, knee correction, white balance adjustment, and compression, as in the DSP 20. The DSP 42 is configured so that processing of data written to the buffer memories 44 and 46 and processing of data read from the buffer memories 44 and 46 and transferred to the memory device 24 can be simultaneously performed.

In this embodiment, the buffer memory 4
4 and 46 use memory elements capable of writing data faster than the writing speed of the memory device 24.

Reference numeral 48 is a sync signal generating circuit for supplying a clock and a sync signal necessary for the image pickup device 16, the A / D converter 18 and the DSP 42, 50 is a system control circuit for controlling the whole, and 52 is a control of the system control circuit 50. Below is a power supply control circuit that controls the power supply to each part of the circuit.

The operation of the embodiment shown in FIG. 6 will be described with reference to the flowcharts shown in FIG. The power switch 34
2 is closed and the system control circuit 50 allows initialization and external interrupts to be the same as that shown in FIG.

When an external interrupt is generated by turning on the switch 38, the system control circuit 50 starts the programs shown in FIG. 7 and subsequent figures. That is, first, the external interrupt is prohibited (S50), and the switch 38 is confirmed (S5).
1). If the switch 38 is off (S51),
When the external interrupt is enabled (S90), the sleep mode is set, and the switch 38 is turned on (S51), the power supply control circuit 52 causes the image sensor 16, the A / D converter 18,
Power is supplied to the DSP 42 and the synchronization signal generation circuit 48 (S5
2).

After supplying power to the image pickup device 16 etc.,
When the previously captured image information is stored in the memories 44 and 46, transfer processing to the memory device 24 is performed (S53).
~ 68). This routine is used, for example, in the continuous shooting mode. Details will be described later.

After processing the data stored in the buffer memories 44 and 46, the system control circuit 50 causes the image sensor 16, A
/ D converter 18, DSP 42 and synchronization signal generation circuit 48
Is operated in the photometry mode (S69), and is operated in the color measurement mode (S70). As in the case of FIG. 1, the DSP 42
In the photometric mode, the subject brightness is calculated by integration with appropriate weighting, and in the colorimetric mode, the color temperature of the subject illumination light is estimated from the subject brightness calculated in the photometric mode. The estimated color temperature adjusts the white balance.

While the switch 38 is on (S71), until the switch 40 is turned on (S91), the processes of the buffer memories 44 and 46 (S52 to 68) and photometry (S69).
And color measurement (S70) are repeated.

When the switch 40 is not turned on but the switch 38 is turned off (S71), all the displays are turned off (S72), and the power source control circuit 52 causes the image pickup device 16, A.
/ D converter 18, DSP 42 and synchronization signal generation circuit 48
The power supply to the memory device 24 is cut off (S73), and the transfer of the data stored in the buffer memories 44 and 46 to the memory device 24 is confirmed (S74 to 79, 80
89), the power supply to the DSP 42, the buffer memories 44 and 46, the interface 26 and the memory device 24 is cut off (S79), the external interrupt is enabled (S90), and the sleep mode is set.

When the switch 40 is turned on by the second stroke of the shutter release (S91), the buffer
The use state of the memories 44 and 46 is checked (S92, 9
3) If both are in use, a warning indicating that imaging is not possible is displayed (S94), the process returns to S52, and the buffer memories 44, 4
If at least one of 6 is usable (S92, 9
3) Take a picture.

That is, the diaphragm 12 is controlled via the diaphragm drive circuit 14 in accordance with the subject brightness calculated in the photometric mode (S13) (S95), and the image sensor 16 is exposed for a predetermined period after removing unnecessary charges. (S96). It is checked whether or not the data in the buffer memory 44 has been transferred to the memory device 24 (S97). If the transfer is completed, the buffer memory 44 can be used, and if the transfer is not completed, the buffer memory 46 can be used.

Here, it is assumed that the buffer memories 44 and 46 can be used together. Power is supplied to the buffer memory 44 (S98), the charge signal due to the exposure of the image pickup device 16 is read out, applied to the buffer memory 44 via the A / D converter 18 and the DSP 42, and writing to the buffer memory 44 is started. Yes (S99). The DSP 42 performs gamma correction and knee correction, adjusts the white balance according to the color temperature in the color measurement mode, and compresses by a predetermined compression method.

It is checked whether the buffer memory 46 is available (S100), and if it is available (that is, the data in the buffer memory 46 has been transferred to the memory device 24) (S100).
100), if power is being supplied to the buffer memory 46, power supply to the buffer memory 46 is cut off (S101, 10).
2) Power is supplied to the interface 26 and the memory device 24 (S103), and transfer of the data in the buffer memory 44 to the memory device 24 is started (S104).

When all the image data of one screen by the image pickup device 16 is written in the buffer memory 44 (S10).
5) The power supply to the image sensor 16 and the A / D converter 18 is cut off (S106). Since the writing speed to the buffer memories 44 and 46 is faster than the writing speed to the memory device 24, the transfer from the buffer memory 44 to the memory device 24 cannot be completed faster than the completion of the writing to the buffer memory 44. ..

It is determined whether the single shooting mode (S) or the continuous shooting mode (C) (S107). If the continuous shooting mode is set, the process returns to the photometry and color measurement routine. On the other hand, in the single shooting mode, while the switch 40 is on (S112), the data in the buffer memories 44 and 46 is continuously transferred to the memory device 24.
That is, the transfer from the buffer memory 46 to the memory device 24 is completed (S113), and the buffer memory 46
If the power is being supplied to (S114), the buffer memory 46
The power supply to the memory device 24 is stopped (S115), and the transfer from the buffer memory 44 to the memory device 24 is started (S116). If the transfer from the buffer memory 46 to the memory device 24 is not completed (S113), or if the transfer is completed, but the power supply to the buffer memory 46 is cut off (S114),
The completion of the transfer from the buffer memory 44 to the memory device 24 is checked (S117), and if the transfer is completed, the power supply to the buffer memory 44, the DSP 42 and the synchronization signal generating circuit 48 is cut off (S118).

For example, when the switch 40 is turned on beyond the time required to transfer one screen of data from the buffer memory 44 to the memory device 24, the buffer memory 44, the DSP 42 and the synchronization signal The power supply to the generation circuit 48 is cut off (S118).

When the switch 40 is turned off (S11
2) If the switch 38 is on, the process returns to the photometric / colorimetric routine. If the switch 40 is turned off before the transfer from the buffer memory 44 to the memory device 24 is completed and the routine returns to the photometry / color measurement routine, the transfer from the buffer memory 44 to the memory device 24 is completed. Detection and power-off of the buffer memory 44 are processed by the photometry / colorimetry routine. That is, when the switch 38 is on, the processing is performed in S53 to 68, and when the switch 38 is off, the processing is performed in S74 to 89.

Next, in the single-shot mode, the buffer memory 44
After writing the captured image information to the buffer memory 44
The operation in the case where the switch 40 is turned off before the transfer from the memory device to the memory device 24 is completed and the switch 38 remains on and returns to the photometric / colorimetric routine will be described.

First, the image sensor 1 is used for photometry and color measurement.
6, power is supplied to the A / D converter 18, the DSP 42, and the synchronization signal generation circuit 48 (S52). The transfer completion from the buffer memory 44 to the memory device 24 is inspected (S53), and the transfer completion from the buffer memory 46 to the memory device 24 is inspected (S63). Here, the buffer memory 46
Since nothing is stored in the memory, the presence / absence of power supply to the buffer memory 46 is inspected (S64). Since the buffer memory 46 is empty, the caution warning display indicating that imaging is not possible is turned off (S68), and photometry (S69) and color measurement (S69) are performed.
70) is executed. Switch 38 is on and switch 40
While the switch is off, the above routine is repeated to wait for the completion of the transfer from the buffer memory 44 to the memory device 24.

An instruction to execute the next photographing (that is, the switch 40
The operation in the case where the transfer from the buffer memory 44 to the memory device 24 is completed (S53) before the turning on) is described. In this case, it is checked whether power is being supplied to the buffer memory 44 (S54). Since power is being supplied in this example,
The power supply to the buffer memory 44 is cut off (S58). S5
9 to 62 are stored in the buffer memory 46 and the memory device 24.
This is the process when the captured image data that has not been transferred is stored in the memory. Since the captured image data is not yet stored in the buffer memory 46 here, it is logically transferred to the memory device 24. Completed (S5
9), the power supply is cut off (S60). After this, after the power is turned on, it is the same as when the switch 38 is first turned on.

Buffer memory 44 to memory device 24
Next shooting instruction (switch 40 on) before transfer to
The case where there is is explained. In the transfer completion check (S92) from the buffer memory 44 to the memory device 24 after the switch 40 is detected to be turned on (S91), of course,
It is determined that the transfer is not completed, and the transfer completion check (S93) from the buffer memory 46 to the memory device 24 causes S
The procedure moves to the imaging routine after 95.

After the aperture control (S95) and the exposure (S96), the transfer completion check from the buffer memory 44 to the memory device 24 (S97) determines that the transfer is incomplete.
Power is supplied to the buffer memory 46 (S119), the captured image signal is read from the image sensor 16, the gamma correction is performed by the DSP 42, and the writing to the buffer memory 46 is started (S120).

Buffer of the image taken by the image pickup device 16
While checking the completion of writing to the memory 46 (S1
21) In the meantime, the completion of the transfer from the buffer memory 44 to the memory device 24 is checked (S122). When the transfer is completed and the power is being supplied (S123), the power supply to the buffer memory 44 is cut off (S1234), -Start transfer from the memory 46 to the memory device 24 (S12
5).

When the writing of the photographed image to the buffer memory 46 is completed (S121), the image pickup device 16 and A /
The power supply to the D converter 18 is cut off (S126), and continuous shooting in the single shooting mode is prohibited (S127 to 135). S12
The processing of 7 to 135 is S107, 112 to 118, 13
Same as 6.

Next, the operation when the writing of the photographed image to the buffer memory 46 is completed earlier than the completion of the transfer from the buffer memory 44 to the memory device 24 will be described.

Upon completion of writing the photographed image in the buffer memory 46 (S121), the image pickup device 16 and the A / D
The power supply to the converter 18 is cut off (S126), and thereafter, the transfer completion from the buffer memory 44 to the memory device 24 is checked regardless of the ON / OFF of the switches 38 and 40, and the transfer completion is transferred to the buffer memory 44. Power is cut off and transfer from the buffer memory 46 to the memory device 24 is started.
From the memory device to the memory device, the buffers 44, 4
6. The power supply to the DSP 42 and the sync signal generation circuit 48 is cut off.

More specifically, while the switch 40 is on, the above-described measures are taken by S129 to S134.
Even when the switch 40 is turned off, while the switch 38 is on (S135), the image sensor 1 is used for photometry and color measurement.
6, power is supplied to the A / D converter 18, the DSP 42, and the synchronization signal generation circuit 48 (S52), the completion of transfer from the buffer memory 44 to the memory device 24 is checked (S53), and when the transfer is not completed, the buffer memory 46 to memory device 2
The completion of the transfer to 4 is inspected (S63).

According to the premise of the explanation of the operation, the transfer from the buffer memory 44 to the memory device 24 is in progress, and the captured image data is held in the buffer memory 46.
Therefore, the transfer from the buffer memory 46 to the memory device 24 has not been completed (S63), and a caution that shooting is not possible is displayed (S67). After that, photometry (S69) and color measurement (S
70) is executed, and while the switch 38 is on and the switch 40 is off, the above routine is repeated to wait for the completion of the transfer from the buffer memory 44 to the memory device 24.

Buffer memory 44 to memory device 24
When the transfer to the buffer memory is completed (S53), the buffer memory 4
4 is cut off (S58), and transfer from the buffer memory 46 to the memory device 24 is started (S62). Since the buffer memory 44 is free, shooting operation is possible,
The caution warning display indicating that imaging is not possible is erased (S68). Thereafter, while the switch 38 is on and the switch 40 is off (S71, 9
1), S53 to 57, 68 to 70 are looped, and when the transfer from the buffer memory 46 to the memory device 24 is completed (S55), the power supply to the buffer memory 46 is cut off (S57).

Buffer memory 44 to memory device 24
When the switches 38 and 40 are both turned off immediately after the transfer to the image sensor 16 and the A / D converter 1
The power supply to No. 8 is cut off (S126), and the switches 38 and 40 are turned off to shift to S72 (S128 and 135).
That is, all the display is turned off (S72), the power supply to the image sensor 16 and the A / D converter 18 is cut off (S73), the data in the buffer memories 44 and 46 is transferred to the memory device 24, and the transfer completed buffer When the power supply to the memory is cut off and the data in the buffer memories 44 and 46 are both transferred to the memory device, the power supply to the DSP 42, the interface 26 and the memory device 24 is cut off (S79), the external interrupt is enabled, and the sleep mode is set. Enter (S90).

In each of the above embodiments, the buffer memory 2
Although volatile memories such as SRAM and DRAM are used for 2, 44 and 46, of course, non-volatile memories may be used. Then, the buffer memories 22, 44, 46
It is possible to limit power supply to only during writing and reading, and further reduce power consumption.

In the embodiment shown in FIG. 6, photography is prohibited when the buffer memories 44 and 46 both hold photographed image data, but photoelectric conversion in the image pickup device 16 is performed according to a special operation. A signal, that is, a charge signal is not read out but is held in the image pickup device 16, and when one of the buffer memories 44 and 46 is empty, the charge signal is read out from the image pickup device 16 and the empty buffer memory 44,
You may make it write in 46. As a special operation for instructing the exposure of the image pickup device 16 and the retention of the charge signal, for example, when the release button is configured to be pushed deeper, a pushing operation or a circuit for monitoring the ON duration of the switch 40 is used. When provided, the switch may be turned on for a predetermined time or longer.

When the image pickup device 16 holds the charge signal of the subject image, the image quality is deteriorated due to dark current, smear, etc., but a desired subject image can be recorded in the memory device 24. At this time, the diaphragm 12 may be maximized to reduce smear.

Holding the charge signal of the subject image in the image pickup device 16 is useful for eliminating the time lag between the release operation and the exposure of the image pickup device 16. Needless to say, it is necessary to continue supplying power to the image sensor 16 until the charge signal is read from the image sensor 16. When the image pickup device 16 holds the charge signal of the subject image, a message to that effect may be displayed on the display device so that reshooting can be selected.

From the image sensor 16 to the buffer memory 22,
Buffer memory 2 before writing to 44 and 46 is completed.
Transfer from 2, 44, 46 to the memory device 24 has started, but in order to reduce the instantaneous value of power consumption, the image sensor 1
It is preferable to start the transfer from the buffer memories 22, 44, 46 to the memory device 24 after the completion of writing from the buffer memory 22, 44, 46 to the memory device 24.

Needless to say, the time required for the rise of the power supply voltage is estimated in advance for starting the power supply to each block.

In this embodiment, since the instantaneous value of power consumption can be reduced, in an apparatus using a battery as a power source, the decrease in output voltage due to the internal resistance of the power source battery can be reduced. The final voltage (lower limit of usable voltage) can be lowered, and secondly, a battery having a larger internal resistance (for example, an alkali manganese battery) can be used.

[0072]

As can be easily understood from the above description, according to the present invention, the instantaneous value of power consumption can be reduced,
For example, even with a small capacity battery, the driving time can be extended.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an embodiment of the present invention.

FIG. 2 is a flowchart of a power-on routine of the embodiment shown in FIG.

FIG. 3 is a part of a flow chart of a photographing operation of the embodiment in FIG.

FIG. 4 is a part of a flowchart of a shooting operation of the embodiment of FIG.

5 is a modification flowchart of FIG. 4. FIG.

FIG. 6 is a configuration block diagram of another embodiment of the present invention.

FIG. 7 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 8 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 9 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 10 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 11 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 12 is a part of a flowchart of a shooting operation of the embodiment of FIG.

FIG. 13 is a part of a flowchart of a shooting operation of the embodiment of FIG.

[Explanation of symbols]

10: Photographing lens 12: Aperture 14: Aperture drive circuit
16: Image sensor 18: A / D converter 20: Digital signal processing circuit 22: Buffer memory 24: Memory device 26: Interface 28: Synchronous signal generation circuit 30: System control circuit 32: Power battery 3
4: Power switch 36: Power control circuit 38, 40:
Switch 42: Digital signal processing circuit 44, 4
6: Buffer memory 48: Synchronous signal generation circuit 5
0: System control circuit 52: Power supply control circuit

Claims (1)

[Claims] 1. An image pickup unit for converting a subject image into an electric signal, a temporary storage unit for temporarily storing image information taken by the image pickup unit, and a recording unit for recording and holding the image information read from the temporary storage unit. A trigger generating means for generating a recording trigger signal, a power supply means for supplying necessary power to the imaging means, the temporary storage means and the recording means, and a trigger signal from the trigger generating means. Power is supplied to the imaging means and the temporary storage means,
The image information to be recorded is written in the temporary storage means, and after the writing in the temporary storage means is started, the recording means is powered to transfer the image information from the temporary storage means to the recording means. , The temporary storage means,
A recording apparatus comprising: the recording means and a control means for controlling the power supply means.