JP3890586B2 - Digital camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been known a digital camera that converts light from a subject into an electrical signal by an optical sensor such as a CCD, converts the converted electrical signal into digital data, and records it on a recording medium such as a flash memory. By using a digital camera, it is possible for an individual to easily store digital data of an image taken using a personal computer or the like and to perform various processes. In addition, by outputting digital data to a printer, a photograph can be printed without developing the film. Recently, improvement in the printing quality of printers has made it possible to output high-quality photos that are indistinguishable from silver halide photos.
[0003]
[Problems to be solved by the invention]
In order to protect the lens, the digital camera as described above includes a lens cover or the like as lens protection means on the subject side of the lens.
If the lens is provided with a lens cover, the user needs to attach and detach the lens cover. Many digital cameras have a lens cover that is independent of the digital camera. Therefore, the power supply of the digital camera can be controlled regardless of whether the lens cover is attached. That is, since shooting is possible even when the user forgets to remove the lens cover, there is a problem that shooting is performed with the cover attached.
[0004]
In addition, there is a digital camera provided with a lens cover that interlocks with a power switch so that shooting is not performed with the cover attached. For example, when the user turns on the power switch of the digital camera, the lens cover provided on the subject side of the lens is automatically moved and stored in a position where it does not interfere with shooting. When the power switch is turned off, the lens cover automatically moves to a position that protects the lens. Thereby, the user does not need to attach or detach the lens cover.
[0005]
However, in order for the lens cover to move automatically, it is necessary to provide driving means for moving the lens cover in the vicinity of the lens. Therefore, there is a problem that the peripheral part of the lens becomes large and the structure becomes complicated. In addition, since the lens cover driving unit consumes power, there is a problem that the life of the battery that is the power supply unit of the digital camera is shortened.
[0006]
SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a digital camera that has a simple structure, can reduce power consumption, and can reduce shooting failures.
[0007]
[Means for Solving the Problems]
According to the digital camera of the first aspect of the present invention, the detection means detects whether or not a lens protection member that is attached and detached by the user is attached. When the detection unit detects that the lens protection member is attached, the power control unit stops the supply of power from the power source unit to the imaging unit while maintaining the supply of power from the power source unit to the display unit. Therefore, it is possible to prevent a failure that the user performs photographing while the lens protection member is mounted. In addition, since it is only necessary to detect whether or not the lens protection member is mounted, the structure is simple, and the drive unit is unnecessary, so that power consumption can be reduced. Furthermore, the image data recorded in the recording unit of the digital camera can be reproduced even with the lens protection member attached.
[0009]
According to the digital camera of the second aspect of the present invention, since the photo sensor detects whether or not the lens protection member is attached, the power consumed by the detecting means can be reduced. According to a third aspect of the present invention, the digital camera further includes means for displaying a warning on the display unit when the lens protection member is attached. Therefore, the user can know that the lens protection member is attached by the warning of the display unit.
[0011]
According to the digital camera of the fourth aspect of the present invention, the warning indicating that the lens protection member is attached continues to display the warning while the lens protection member is attached. Therefore, the user can continuously know that the lens protection member is attached.
[0012]
According to the digital camera of the seventh aspect of the present invention, when the lens protection member is mounted, the supply of power to the imaging unit is cut off. That is, processing other than shooting, for example, reproduction of image data recorded in the recording unit of the digital camera, or setting of the digital camera can be executed. Therefore, if the process is not a shooting execution process, the process can be executed with the lens protection member attached.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plurality of examples showing embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 2 shows a digital camera according to a first embodiment of the present invention.
[0014]
As shown in FIG. 2, the digital camera 1 includes a control unit 2, a lens unit 3, a CCD (Charge Coupled Device) 5, an A / D converter 6, a RAM (Random Access Memory) 7, a power supply unit 8, and a display unit. An LCD (Liquid Crystal Display) 9, a VRAM (Video RAM) 10, a flash memory 11, an interface 12, a shutter button 13, an input unit 14, and the like are included.
[0015]
The control unit 2 includes a central processing unit (CPU) and a ROM in which programs for performing various controls of the digital camera 1 are recorded. Connected to the control unit 2 are a shutter button 13 for instructing the start of shooting and an input unit 14 for inputting a plurality of setting information to the digital camera 1.
[0016]
The lens unit 3 includes a lens group 31 in which a plurality of convex lenses and concave lenses are combined. The lens unit 3 is provided with lens cover detection means 33 for detecting whether or not a lens cover 32 as a lens protection member is attached.
[0017]
The lens unit 3 collects light from the subject and makes it incident on the CCD 5. A color image is taken by using the CCD 5 in which an image sensor having complementary color filters of C (Cyan), M (Magenta), Y (Yellow), and G (Green) is arranged on a matrix. As complementary color filters, filters of three colors C, M, and Y may be used. A CCD having primary color filters of R (Red), G (Green), and B (Blue) may be used.
[0018]
The A / D converter 6 converts light from the subject into digital image data by converting an analog electrical signal output from the CCD 5 into a digital signal.
The RAM 7 temporarily stores image data converted by the A / D converter 6 or image data obtained by developing compressed image data recorded in the flash memory 11. As the RAM 7, a DRAM (Dynamic RAM) having a self-refresh function is used.
[0019]
The LCD 9 displays an image created from the image data. The LCD 9 is used as a viewfinder at the time of shooting or reproduces and displays an image based on the compressed image data recorded in the flash memory 11. The VRAM 10 stores image data of an image displayed on the LCD 9. As the display unit, not only the LCD 9 but also a light emitting diode (not shown) is used in combination.
[0020]
The flash memory 11 is a rewritable storage medium that can hold the contents of recorded data without being energized. The flash memory 11 is built in the digital camera 1 or detachably provided in a card slot (not shown) of the digital camera 1. As the flash memory 11, for example, by using a memory card conforming to the PCMCIA standard or a memory card attached to a PCMCIA card adapter, the contents of the flash memory 11 are directly read and written by a personal computer having a PCMCIA card slot.
[0021]
The interface 12 is connected to a cable for outputting the contents stored in the flash memory 11 to an external processing device such as a personal computer. As a standard of the interface 12, a parallel system, a USB (Universal Serial Bus) system, or the like is used.
[0022]
The shutter button 13 reciprocates in the vertical direction in FIG. The control unit 2 distinguishes between a “half-pressed” state in which the shutter button 13 is pushed halfway through the movable range and a “full-pressed” state in which the shutter button 13 is pushed to the vicinity of the limit of the movable range via a shutter stroke detection unit (not shown). recognize.
[0023]
The power supply unit 8 supplies power not only to the image pickup unit such as the CCD 5 but also to circuits constituting each unit of the digital camera 1. The power supply unit 8 includes a battery 81 as a power supply source and a power supply circuit 82 connected to the lens cover detection unit 33. As the battery 81, for example, a secondary battery such as a nickel metal hydride battery is used. Further, the control unit 2 is always supplied with electric power.
[0024]
Next, the lens cover detection means 33 will be described in detail.
As shown in FIG. 1, on the subject side of the outermost lens 31a of the lens group 31, a lens cover 32 for protecting the surface of the lens 31a of the lens group 31 is detachably provided. The lens cover detection means 33 detects whether or not the lens cover 32 is attached to the subject side of the lens 31a.
[0025]
The lens cover detection means 33 includes a contact ring 331 as a contact member that contacts the lens cover 32 and a movement detection switch 332 as a movement detection member that detects the movement of the contact ring 331. The contact ring 331 and the movement detection switch 332 are provided in an annular shape so as to surround the lens group 31 between the lens support member 311 that supports each lens of the lens group 31 and the lens barrel 312. The contact ring 331 is urged in the direction of the lens cover 32 by the urging member 333, and moves in the left-right direction in FIG. Further, the contact ring 331 and the movement detection switch 332 constitute power control means.
[0026]
The entire contact ring 331 or the end of the movement detection switch 332 is formed of a metal member. A power supply path 331a is connected to the contact ring 331, and the end opposite to the connection side of the contact ring 331 is connected to the CCD 5 and the A / D converter which are the imaging unit of the digital camera 1 via the control unit 2. 6 is connected. The movement detection switch 332 is made of a metal member. The movement detection switch 332 is connected to the battery 81 of the power supply unit 8 via the power supply circuit 82.
[0027]
When the lens cover 32 is attached and the contact ring 331 moves to the right in FIG. 1, the end of the contact ring 331 and the movement detection switch 332 contact each other. As a result, the end of the contact ring 331 and the movement detection switch 332 are energized, and power is supplied from the battery 81 of the power supply unit 8 to the CCD 5 and the A / D converter 6 of the digital camera 1.
[0028]
Next, the operation of the digital camera of this embodiment will be described.
(1) When the user removes the lens cover 32, the power switch (not shown) of the digital camera 1 is set to "ON", and the mode conversion switch (not shown) is set to the "View" mode, the digital camera 1 enters a standby state in which a subject can be photographed. Become. At this time, in the CCD 5, the light collected by the lens group 31 is converted into an electrical signal corresponding to the amount of light every second to several tens of seconds. The converted electrical signal is converted into digital image data by the A / D converter 6. When the user uses the LCD 9 as a viewfinder, the image data converted into a digital signal is transferred to the VRAM 10 and the subject is displayed on the LCD 9 as a moving image.
[0029]
(2) When the lens cover 32 is attached to the digital camera 1, the contact ring 331 and the movement detection switch 332 are not in contact with each other even if the user turns on the power switch. No current flows between the movement detection switches 332. Therefore, no power is supplied from the power supply unit 8 to the CCD 5 and the A / D converter 6 of the digital camera 1, and the user cannot perform photographing. At this time, a warning indicating that the lens cover 32 is attached is displayed on the LCD 9. This display is continuously displayed until the lens cover 32 is removed. Moreover, it is good also as a structure which the light emitting diode which is not shown in figure instead of LCD9 blinks, for example.
[0030]
(3) After the power source of the digital camera 1 is turned “ON”, when the user presses the shutter button 13 and enters the “half-pressed” state, the exposure and focus are set and fixed. The exposure at the time of photographing can be changed by the control unit 2 controlling the aperture and shutter speed of the lens group 31, that is, the charge accumulation time of the CCD 5, based on the light amount data output from the CCD 5. As the shutter of the digital camera 1, either one or both of a mechanical shutter that physically blocks light and an electronic shutter that controls the charge accumulation time of the CCD 5 are used.
[0031]
(4) When the shutter button 13 is pushed in by the user to enter the “full press” state, the following processing is performed. First, accurate photometry and focusing are performed on the subject. When photometry and focusing are completed, all the charges accumulated in the CCD 5 are once discharged, and then light from the subject condensed by the lens group 31 enters the CCD 5. The CCD 5 outputs an electrical signal based on the amount of charge corresponding to the amount of incident light.
[0032]
(5) The electrical signal output from the CCD 5 is converted into image data by the A / D converter 6. The converted digital image data is temporarily stored by designating the address of the RAM 7 directly without using the control unit 2 by DMA (Direct Memory Access) for speeding up.
[0033]
(6) The digital image data stored in the RAM 7 is subjected to various corrections such as white balance adjustment, interpolation processing, and color correction, and then a file such as JPEG is used to increase the number of recordings in the flash memory 11. Compressed digital image data in the format. The JPEG file is created by software by the control unit 2 using a predetermined algorithm, and a dedicated circuit can be provided for speeding up.
[0034]
(7) When the compression of the digital image data is completed, the image data is copied from the RAM 7 to the flash memory 11 and recorded.
(8) When changing the shutter speed or exposure of the digital camera 1 without executing the shooting, the digital camera 1 can be operated even with the lens cover 32 attached. In this case, the user turns on the power of the digital camera 1 and sets the mode conversion switch to “Set”.
[0035]
(9) Even when image data recorded in the flash memory 11 is reproduced on the LCD 9, the digital camera 1 can be operated with the lens cover 32 attached. In this case, the user sets the power switch of the digital camera 1 to “ON” and the mode conversion switch to “Play”.
[0036]
As described above, according to the first embodiment of the present invention, when the lens cover 32 is attached, the contact ring 331 is moved by the lens cover 32 and the contact between the contact ring 331 and the movement detection switch 332 is released. . As a result, the contact ring 331 and the movement detection switch 332 are in a non-energized state, so that power is not supplied from the battery 81 of the power supply unit 8 to the CCD 5 and the A / D converter 6 that are the imaging unit of the digital camera 1. That is, when the user forgets to remove the lens cover 32, the power of the CCD 5 and the A / D converter 6 of the digital camera 1 is not turned “ON”, so that photographing cannot be executed. Since the LCD 9 displays a warning that the lens cover 32 is attached, the user can easily know that the lens cover 32 is attached. Therefore, unless the lens cover 32 is removed, the power of the CCD 5 and the A / D converter 6 is not turned “ON”, so that shooting failures caused by the user performing shooting while wearing the lens cover 32 can be reduced. it can.
[0037]
Further, since it is detected whether or not the lens cover 32 is attached by contact between the contact ring 331 and the movement detection switch 332, the structure is simple and electric power is required to detect the attachment of the lens cover 32. And not. Therefore, the power consumed by the digital camera 1 can be reduced, and the life of the battery 81 can be extended.
[0038]
Furthermore, according to the digital camera 1 of the present embodiment, even when the lens cover 32 is attached, processing other than shooting, for example, reproduction processing of image data recorded in the flash memory 11, or digital camera 1 When setting processing such as shutter speed or exposure setting is performed, power is supplied to each unit. Therefore, the user can operate the digital camera 1 while wearing the lens cover 32.
[0039]
(Second embodiment)
A second embodiment of the present invention is shown in FIG. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
As shown in FIG. 3, the digital camera 1 of the second embodiment is different from the first embodiment in the configuration for detecting the lens cover 32 of the lens cover detection means 34.
[0040]
In the lens cover detection means 34 of the second embodiment, a photosensor 35 is provided on a lens barrel 312. The photo sensor 35 senses whether or not the lens cover 32 is attached to the subject side of the lens 31a. The photosensor 35 is connected to the control unit 2 via the power control circuit 36. When the photosensor 35 senses the attachment of the lens cover 32, the control unit 2 causes the current control circuit 36 as a power control unit to flow current. Is cut off.
[0041]
If the photosensor 35 does not sense the attachment of the lens cover 32, the control unit 2 releases the current flow of the power control circuit 36, and the power source unit 8 is connected to the CCD 5 and the A / D converter 6 that are the imaging unit of the digital camera 1. Is supplied with power.
When using the photo sensor 35, when the user turns on the power switch of the digital camera 1 (not shown), power is supplied from the power supply unit 8 to the control unit 2. The control unit 2 to which power is supplied determines whether or not the photo sensor 35 senses attachment of the lens cover 32. The control unit 2 controls the power control circuit 36 depending on whether or not the photo sensor 35 senses the attachment of the lens cover 32, and intermittently supplies power from the power supply unit 8.
[0042]
As described above, according to the digital camera 1 of the second embodiment, the mounting of the lens cover 32 can be detected without requiring a mechanical configuration. Therefore, the structure becomes simpler and the manufacturing cost can be reduced. In addition, since the power required to detect the lens cover 32 is very small, the power consumed by the digital camera 1 can be reduced.
[0043]
(Third embodiment)
A third embodiment of the present invention will be described.
In the third embodiment, when the power switch of the digital camera 1 is turned “ON” while the lens cover 32 is attached, a warning indicating that the lens cover 32 is attached is displayed on the LCD 9. This warning display is displayed for a predetermined time, for example, 1 minute. When one minute has elapsed since the power switch was turned “ON”, the power supply from the power supply unit 8 of the digital camera 1 is stopped, the digital camera 1 is turned “OFF”, and the LCD 9 on which a warning is displayed is displayed. The power supply is stopped.
[0044]
In the third embodiment, the power of the LCD 9 is turned “ON” for a predetermined time after the power switch of the digital camera 1 is turned “ON”, and a warning indicating that the lens cover 32 is attached is displayed. The user can easily know from the warning that the lens cover 32 is attached. Further, since the power supply of the digital camera 1 is turned “OFF” after a predetermined time has elapsed, unnecessary power is not consumed by the digital camera 1 and the life of the battery 81 of the power supply unit 8 can be extended.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a digital camera according to a first embodiment of the present invention and enlarging the vicinity of a lens group.
FIG. 2 is a block diagram illustrating a digital camera according to a first embodiment of the present invention.
FIG. 3 is a sectional view showing a digital camera according to a second embodiment of the present invention and enlarging the vicinity of a lens group.
[Explanation of symbols]
1 Digital Camera 3 Lens Unit 5 CCD (Imaging Unit)
6 A / D converter (imaging part)
8 Power supply unit 9 LCD (display unit)
32 Lens cover (lens protection member)
33, 34 Lens cover detection means (lens protection member detection means)
35 Photosensor 36 Power control circuit (power control means)
331 Contact ring (lens protection member detection means, power control means)
332 Movement detection switch (lens protection member detection means, power control means)

Claims (4)

A power supply for supplying power;
A lens that collects light from the subject,
An imaging unit that is supplied with power from the power supply unit and converts light from the subject collected by the lens into image data;
A display unit capable of displaying an image created from the image data;
A lens protection member detachably provided on the subject side of the lens;
Detecting means for detecting whether or not the lens protection member is mounted;
A power control unit that shuts off the supply of power from the power supply unit to the imaging unit while maintaining the supply of power from the power supply unit to the display unit when the detection unit detects attachment of the lens protection member; ,
A digital camera comprising:   The digital camera according to claim 1, wherein the detection unit includes a photosensor.   3. The digital camera according to claim 1, further comprising warning display means for displaying a warning on the display unit when the detection means detects the mounting of the lens protection member.   4. The digital camera according to claim 3, wherein the warning displayed on the display unit continues to be displayed while the lens protection member is mounted.

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