JP2004056690A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital camera in which an image photographed in the past can be easily confirmed without complicated operation. <P>SOLUTION: An electronic display sheet 180 is used on a display screen. Even when a power source is switched to the off side, the image displayed at last remains as it is, photographic history is confirmed when the power source is re-applied, the image is rewritten and a subject image is displayed after the power source is re-applied in a photographic mode. The photographic history is confirmed even after the power source is re-applied in a reproduction mode, the image is rewritten by switching the mode to the photographic mode when the rewriting is desired to be performed and a new subject image is displayed. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera that obtains image data by forming an image of a subject on an image sensor.
[0002]
[Prior art]
Many digital cameras include a display device, and an LCD display device is often used as the display device. This LCD display device is volatile, and when the power is switched to the off side, the image displayed on the LCD display device disappears. In such a digital camera, the user often switches the power supply in consideration of battery consumption. When the photographer wants to check a picture taken in the past, the power is turned on again and again. Thus, it is necessary to switch to the playback side, and display and confirm images taken in the past on the display device. Therefore, in order to be able to check an image taken in the past without forcing the user to perform such a complicated operation, the one disclosed in Japanese Patent Laid-Open No. 7-193770 is the same as the start of reproduction. A technique for automatically reproducing the last photographed image is introduced. Japanese Patent Laid-Open No. 2000-138892 introduces a technique for displaying a large number of images captured in the past on a multi-screen so that images captured in the past can be confirmed at a time.
[0003]
In place of such a volatile display device, a nonvolatile display device has been developed, but has not yet been put into practical use. As such a non-volatile display device, there is one described in Japanese Patent Laid-Open No. 2000-162650.
[0004]
[Problems to be solved by the invention]
However, in any of the above-mentioned Japanese Patent Laid-Open Nos. 7-193770 and 2000-138892, when the power is switched to the off side, the displayed image disappears and the user took a picture in the past. There is a problem that a complicated operation must be performed when it is desired to check the image.
[0005]
Further, although the nonvolatile display device described in Japanese Patent Application Laid-Open No. 2000-162650 has been developed, there is no example applied to a digital camera yet.
[0006]
SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a digital camera that can easily check images captured in the past without complicated operations.
[0007]
[Means for Solving the Problems]
The camera of the present invention that achieves the above object is a digital camera that obtains image data by imaging a subject on an image sensor.
Non-volatile display means for rewritably displaying an image based on image data obtained by the image sensor is provided.
[0008]
Here, the display means is
The colored particles are dispersed in the suspension, and a fixed image is displayed even after the voltage application is canceled by electrophoresis according to the application of the voltage of the colored particles based on the image data. An electronic display sheet that can be rewritten,
It is preferable that the electronic display sheet includes a driver that applies a voltage corresponding to the image data.
[0009]
According to the present invention, even when the power is switched to the off side, the last photographed image remains displayed on the non-volatile display means such as an electronic display sheet. Then, the user can always check the last photographed image without performing complicated operations.
[0010]
Also, when the camera is in the shooting mode when the power is turned on again, the images shot in the past are still displayed, so that the shooting history of the digital camera becomes clear at a glance. Further, since it is rewritable, when the power is turned on and a new image is taken, or when another image is instructed to be displayed, a new image is displayed on the display means, and the image captured in the past is erased.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0012]
FIG. 1 is a perspective view of a configuration of a digital camera showing an embodiment of the present invention. FIG. 1A is a view seen from the upper front side, and FIG. 1B is a view seen from the upper rear side.
[0013]
As shown in FIG. 1A, in the digital camera 100 of the present embodiment, an image of a subject is guided to a CCD solid-state imaging device provided in the digital camera 100 through a photographing lens incorporated in the lens barrel 170. It is like that. A distance measuring device is provided inside the digital camera 100, and a light projecting window 103 and a light receiving window 104 are provided on the camera body. In this distance measuring device, light is projected toward the subject through the light projection window 103, and the return light returning to the subject is received through the light receiving window 104 to perform distance measurement. A finder objective window 105 is provided at a position between the light receiving window 104 and the light projecting window 103.
[0014]
In addition, a photometric device is also provided inside the digital camera 100, and subject brightness is detected from subject light guided through a photographing lens built in the lens barrel 170.
[0015]
Further, a flash light emission window 160a including a Fresnel lens 160b is fitted into the camera body, and flash light emitted from a flash light emission unit provided in the digital camera 100 is irradiated toward the subject through the flash light emission window 160a.
[0016]
As illustrated in FIG. 1B, an operation unit for performing various operations when the user uses the digital camera 100 is provided on the back surface of the digital camera 100 according to the present embodiment.
[0017]
The operation unit is provided with an operation switch group 101 and an image display sheet 180. In addition to the power switch 101a for operating the digital camera 100, the switch group 101 includes a cross key 101b, a menu / OK key 101c, a cancel key 101d, a mode lever 101e, and the like. In addition, an operation LCD display unit 101f for displaying an operation content to the user is provided inside the cross key 101b.
[0018]
As shown in FIG. 1B, a release button 102 is provided above the digital camera 100. The release button 102 transmits a shooting start instruction to the signal processing unit inside the digital camera 100. In this digital camera 100, shooting and playback can be switched by a mode lever 101e. The user switches the mode lever 101e to the shooting side when shooting, and the mode lever 101e is switched to the playback side when playing. .
[0019]
FIG. 2 is a configuration block diagram of a signal processing unit provided in the digital camera 100. The configuration of the signal processing unit in the digital camera 100 will be described with reference to FIG.
[0020]
FIG. 2 is a configuration block diagram of a signal processing unit provided in the digital camera 100.
[0021]
In the digital camera 100 of this embodiment, all processes are controlled by the main CPU 110, and various switch groups 101 of the operation unit shown in FIG. 1B are connected to the input unit of the main CPU 110, respectively. An EEPROM 110a is connected to the main CPU 110, and a program necessary for operating as the digital camera 100 is written in the EEPROM 110a. When the power switch 101a of the digital camera is turned on, the operation of the entire digital camera is controlled by the CPU 110 according to the procedure of the program.
[0022]
First, the flow of captured image data will be described with reference to FIG.
[0023]
When the power switch 101a is turned on, the main CPU 110 detects that the power switch 101a is turned on, and power is supplied from the power supply 130 to each block such as the main CPU 110 and the photometric distance measuring CPU 140. If the mode lever 101e is switched to the photographing side when the power supply 130 is turned on, first, the subject image formed on the CCD solid-state photographing element 110 is thinned out at predetermined intervals and read out as image data. Thus, a subject image in the direction in which the photographing lens is directed is displayed on the electronic display sheet 180. The image data read out after being thinned out from the CCD solid-state imaging device 111 is composed of RGB signals, and the RGB signals are supplied to the white balance adjustment / γ processing unit 112.
[0024]
The white balance adjustment / γ processing unit 112 is supplied with a timing signal from a clock generator (hereinafter referred to as CG) 141, and processing such as white balance / γ processing is performed based on the timing signal. At 112.
[0025]
In normal daytime shooting, the white balance / γ processing unit 112 converts the image data obtained by the CCD solid-state imaging device based on the measurement result of a photometric device (not shown) into a white balance corresponding to the color temperature of the outside world, for example, 6000K. Adjustments are made. When shooting with flash is performed at night, the white balance / γ processing unit 112 adjusts the image data obtained by the CCD solid-state imaging device to white balance corresponding to the color temperature of the flash, for example, 4700K. .
[0026]
Further, the signal converted into digital image data by the A / D conversion unit 113 is supplied to the buffer memory 114 and transferred from the buffer memory 114 to each processing unit via the bus 115. First, the RGB signal transferred to the YC processing unit 116 is converted into a YC signal, and the converted YC signal is supplied to the electronic display sheet 180 side. There is a YC → RGB conversion unit 181 for converting the YC signal into the RGB signal in the front stage of the electronic display sheet 180. The YC → RGB conversion unit 181 converts the YC signal into the RGB signal again, and the converted RGB signal is converted into the RGB signal. The electronic display sheet 180 is supplied via the driver 182. Based on the supplied RGB signals, the electronic display sheet 180 displays an image of the subject image. Since the image data of the CCD solid-state imaging device 111 is thinned out and read out at predetermined intervals based on the timing signal supplied from the CG 141 described above, in this electronic display sheet 180, the photographing lens 170 is provided. A subject in the directed direction is always displayed as a subject image.
[0027]
When the release button 102 is pressed here, all image data imaged on the CCD solid-state image sensor 111 when the release button 102 is pressed are read out as RGB signals, and the YC processing unit 116 reads them. The RGB signal is converted into a YC signal, and the image data is further compressed by the compression / expansion circuit and ID extraction unit 120 and recorded in the memory card 122 via the I / F 121. The recorded image data is JPEG compressed, and is recorded on the memory card 122 as an EXIF file. This EXIF file is provided with a header portion in which shooting information and the like are written. Therefore, when the playback side is switched and the EXIF file is read from the memory card 122, the compressed image data is expanded. At this time, an ID is extracted from the header information of the EXIF file, a process suitable for the shooting conditions is performed, and the subject image is displayed on the electronic display sheet 180.
[0028]
In addition to the main CPU 110, the digital camera 100 of this embodiment is provided with a dedicated photometry / ranging CPU 140 for performing focus adjustment and exposure adjustment. The photometry / ranging CPU 140 is charged / emitted. A control unit 142 is connected. The photometry / ranging CPU 140 controls a photometry device and a distance measurement device (not shown). Further, the charge / light emission control unit 142 controls the flash light emission unit 160 based on the measurement results of the photometry device and the distance measurement device controlled by the photometry / range measurement CPU 140. In the photometry / ranging CPU 140, the focus lenses 151a and 151b are driven to the in-focus position based on the measurement result of the distance measuring device in the focus adjustment, and the aperture 152 based on the measurement result of the photometry device in the exposure adjustment. The amount of light applied to the imaging surface of the CCD solid-state imaging device 111 is controlled by changing the size of the aperture of the. In this exposure adjustment, the photometry / ranging CPU 140 performs, for example, disposing one of the two apertures on the optical axis.
[0029]
A dedicated photometry / ranging CPU 140 that performs such adjustments as focus, focal length, and exposure and a main CPU 110 that controls the operation of the entire camera exchange data according to the processing status. Each part is controlled by the main CPU 110 and the photometry / ranging CPU 140 in accordance with the processing status of the process performed in the above, and the operation as a digital camera is controlled.
[0030]
The digital camera 100 of this embodiment is also provided with a menu key 101c. When the menu key 101c is operated, a selection menu is displayed on the electronic display sheet 180. The cursor can be moved by operating the cross key 101b to an arbitrary position in the displayed selection menu. The cross key 101 is provided with an up key, a down key, a right key, and a left key. When any of the keys is operated, the CPU 111 detects the operation instruction content, and based on the detected content. The control signal is transferred to the electronic display sheet 180 via the bus 115, and the cursor moves between a plurality of selection items displayed on the menu screen. Therefore, the user can select a favorite item only by operating the cross key 101a to move the cursor displayed on the electronic display sheet 180 to his favorite place and pressing the menu / OK key 101c.
[0031]
As described above, an electronic display sheet is used for a display that displays a subject image and a menu.
[0032]
This electronic display sheet 180 is equivalent to that described in JP 2000-162650 A, and a cell in which a suspension and a large number of colored particles are sealed between a pair of transparent electrodes. Many are arranged.
[0033]
FIG. 3 is a diagram conceptually showing the structure of one cell. The principle will be described with reference to FIG.
[0034]
As shown in FIG. 3, one cell 1800 includes a glass plate 1800a, a pair of transparent electrodes 1801a and 1801b, a suspension liquid 1802, a large number of colored particles 1803, spacers 1804a and 1804b, and a substrate 1805. .
[0035]
A large number of colored particles 1803 are mixed in the suspension liquid 182, and the suspension liquid 1802 and the large number of colored particles 1803 are sealed with a pair of transparent electrodes 1801a and 1801b and a pair of spacers 1804a and 1804b. . When one transparent electrode 1801a is connected to the ground and one of positive and negative voltages is applied to the other electrode 1801b, the colored particles 1803 migrate and collect on either electrode side.
[0036]
FIG. 3 shows a state when colored particles are collected on either electrode side.
[0037]
The left side of FIG. 3 shows a state in which a positive voltage is applied to the lower electrode 1801b in the drawing. A large number of colored particles 1803 are collected on the viewer side, and the viewer sees colored particles 1803. Color, eg white, is observed. Further, the right side of FIG. 3 shows a state when a negative voltage is applied to the lower electrode in the figure, and the color of the suspension liquid is observed without observing the color of the colored particles by the observer. Black is observed. A large number of such cells 1800 are arranged to constitute the electronic display sheet 180.
[0038]
FIG. 4 is a conceptual diagram showing a configuration of a driver 182 for driving the electronic display sheet 180.
[0039]
As shown in FIG. 4, a large number of cells 1800 are arranged in the vertical and horizontal directions. In the following description, the vertically arranged cell groups are referred to as column cells, and are denoted as column 1 to column 8, respectively. A group of cells arranged horizontally is referred to as a row cell row and is denoted as row1 to row7, respectively. When any one of these row cells row1 to row7 is selected by the decoder 182a, and any of these column cells column1 to column7 is selected by the line driver 182b, any of the cells arranged in the vertical and horizontal directions is selected. A voltage is applied to the cell 1800.
[0040]
The decoder 182a shown on the left side of FIG. 4 functions as an address line. When the row cell, for example, row2 is selected by the decoder 182a, and for example, the column cell column4 is selected by the line driver, the hatched cell 1800 is selected. The When one of the decoder 182a and the line driver 182b is appropriately selected in this manner, a predetermined portion of cells is colored with colored particles.
[0041]
For example, data corresponding to an address may be supplied to the decoder 182a via the bus 115, and serial conversion is performed after parallel data is supplied to the YC → RGB conversion unit sheet 181 via the bus 115 on the data input side. The serial data thus obtained may be supplied via the driver 182. For example, when the data string is data 0, 0, 0, 1, 0, 0, 0, 0 and the decoder 182a is supplied with data corresponding to the address signal 2 from the bus 115 side, the row cell row2 is selected. Only the hatched cells are colored, and the subject image is observed from the observer side.
[0042]
In this way, when the address supplied to the decoder 182a is changed variously at predetermined intervals and the data supplied to the shift register is changed variously at predetermined intervals, different subject images can be displayed. .
[0043]
That is, if different voltages are applied to the respective cells 1800 at a predetermined time, different subject images are displayed. If the subject image is to be left as it is, it is not necessary to apply appropriate data to the decoder and line driver and apply a voltage to the cell.
[0044]
As described above, any one of the decoder lines 182a is designated based on the image data, and further, data corresponding to the image data is input to the shift register 182d side and written to the storage register 182c to apply voltage to the cell to be colored. Is applied, only the colored particles of the cell to which the voltage is applied migrate and are collected on one of the electrodes, so that a desired subject image is displayed on the electronic display sheet. If no voltage is applied to the electronic display sheet 180, electrophoresis does not occur in the colored particles 1803 in the suspension liquid 1802, and the position of the colored particles 1803 does not move, so that the displayed image is held as it is.
[0045]
When the power is turned off, the decoder 182a or the line driver 182b is not driven, so that the colored particles 1803 remain collected on either electrode side, and the subject image is held semipermanently.
[0046]
In this way, since the subject image taken in the past remains on the electronic display sheet without turning on the power again, it is necessary to manually turn on the power and switch to the playback mode. It is not necessary to display the image on the display panel.
[0047]
【The invention's effect】
As described above, according to the camera of the present invention, it is possible to provide a digital camera that can easily check images taken in the past without complicated operations even after the power is switched off. Can do.
[Brief description of the drawings]
FIG. 1 is a diagram showing an external appearance of a digital camera showing an embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration inside the digital camera shown in FIG. 1;
FIG. 3 is a diagram conceptually showing the structure of one cell of an electronic display sheet.
FIG. 4 is a conceptual diagram illustrating a configuration of a driver for driving an electronic display sheet.
[Explanation of symbols]
100 Digital Camera 101a Power Switch 101b Cross Key 101c Menu / OK Key 101d Cancel Key 101e Mode Switch 101f Operation LCD Display Unit 102 Release Button 103 Light Emitting Window 104 Light Receiving Window 105 Viewfinder Objective Window 110 Main CPU
110a EEPROM
111 CCD solid-state imaging device 112 White balance and γ processing unit 113 A / D conversion unit 114 Buffer memory 115 YC processing unit 116 Electronic zoom processing unit 120 Compression / decompression / ID extraction unit 121 I / F
122 Memory card 130 Power supply 140 Metering / ranging CPU
141 CG
142 Charging / Light Emission Control Unit 150 Imaging Optical System 151 Focus Lens 152 Aperture 160 Flash Light Emitting Unit 160a Flash Light Emission Window 160b Fresnel Lens 160c Xenon Tube 160d Reflector 161 Motor 170 Lens Body 171a 171b Focus Lens 172 Aperture 180 Electronic Display Sheet 1801a Cell 1800a Glass plate 1801a 1801b Transparent electrode 1802 Suspended liquid 1803 Colored particles 1804a 1804b Spacer 180a Display surface 181 YC → RGB conversion unit 182 Driver

Claims (2)

In a digital camera that obtains image data by imaging a subject on an image sensor,
A digital camera comprising a non-volatile display means for rewritably displaying an image based on image data obtained by the image sensor. The display means includes
The colored particles are dispersed in the suspension, and a fixed image is displayed even after the voltage application is canceled by electrophoresis according to the voltage application of the colored particles based on the image data. An electronic display sheet that can be rewritten,
The digital camera according to claim 1, further comprising a driver that applies a voltage corresponding to image data to the electronic display sheet.

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