JP2000050138A - Digital camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital camera in which an image pickup part having an optimum photographing lens corresponding to a photographing purpose can arbitrarily be exchanged/used. SOLUTION: A digital camera is provided with an image pickup part 3 having a photographing lens 301 and an imaging device 303 which photoelectrically coverts an object image which is formed by the photographing lens 301 and a camera body part 2 having an image processing part which image-processes an electric signal from the imaging device 303, and the image pickup part 3 is attachably/detachably installed in the camera body part 2. Plural image pickup parts different in types can be exchanged/installed. When the image pickup part 3 provided with the photographing lens adjusted to a photographing purpose is selectively used, the optimum imaging device corresponding to the photographing lens can automatically be set and the operability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a digital camera.

[0002]

2. Description of the Related Art As a digital camera, a camera body having a photographing lens and an image pickup device for photoelectrically converting a subject image formed by the photographing lens, and an image processing unit for image processing an electric signal from the image pickup device. There are some which are constituted by the divisions.

[0003] As the image pickup device, a charge coupled device (CCD) as a photoelectric conversion device is used.
ce) is commonly used. When an optical image of the subject from the photographing lens is formed on the light receiving surface of the CCD, the optical image is photoelectrically converted by the CCD, and an electric signal from the CCD is subjected to predetermined image processing to become image data.

Conventionally, there has been known a digital camera in which an image pickup unit having a photographing lens and a CCD is detachably mounted on a camera body. This digital camera has an advantage that the degree of freedom of displacement of the imaging unit is increased by connecting the imaging unit and the camera main body with a cable, so that the imaging can be performed at a free angle.

[0005]

By the way, it is convenient for the photographer if a plurality of photographing lenses can be selectively used according to the photographing purpose. However, in a conventional digital camera in which the image pickup unit is detachable from the camera body, the image pickup unit cannot be replaced with another type, so that an optimal photographing lens is set according to the photographing purpose. There was a drawback that it was not easy to use.

[0006] On the other hand, there is also known a camera in which a CCD is arranged near a film gate of a silver halide single-lens reflex camera body so that an image can be captured by a lens for a silver halide single-lens reflex camera. However, in this case, although the photographing lens can be replaced, the CCD cannot be replaced.Therefore, depending on the type of silver halide single-lens reflex lens, matching with the image sensor may not be sufficient, and the usable photographing lens is limited. There was a disadvantage that it was done.

The present invention has been made in view of such technical background, and provides an easy-to-use, convenient digital camera that can arbitrarily replace and use an image pickup section having an optimum photographing lens according to a photographing purpose. As an issue.

[0008]

An object of the present invention is to provide an image pickup unit having a photographing lens and an image pickup device for photoelectrically converting a subject image formed by the photographing lens, and an image processing for image processing an electric signal from the image pickup device. A digital camera that comprises a camera main body having a portion, and wherein the imaging unit is detachably mounted to the camera main body, a plurality of different types of imaging units are configured to be exchangeably mountable to the camera main body. It is solved by a digital camera characterized in that:

According to this digital camera, the image pickup section having the photographing lens and the image pickup element can be exchanged for another type with respect to the camera body, and the image pickup section having the photographing lens suitable for the photographing purpose can be provided. If selected, the optimum image sensor corresponding to the above-mentioned photographing lens is automatically set, and the usability is improved. In other words, it is possible to select an optimal pair of a photographing lens and an image pickup device that suits the purpose.

[0010] Further, the camera body includes a detecting means for detecting the type of the image pickup section, and a control means for controlling the camera body in accordance with the output of the detecting means. Is good.

According to this digital camera, the type of the imaging unit is detected, and the camera body is controlled in accordance with the detection. Therefore, optimal control according to the type of the imaging unit is performed.

Alternatively, the camera body may include a detecting unit for detecting the type of the image pickup unit, and a display unit for displaying a detection result of the detecting unit.

In this digital camera, since the type of the imaging unit is detected and displayed on the display means, the type of the mounted imaging unit can be grasped at a glance.

[0014] The image pickup section includes storage means for storing the type of the image pickup section, while the camera body section obtains information on the image pickup section from the storage means when the power switch is turned on. In the case where an information acquisition unit is provided, the type of the imaging unit can be immediately known at the same time when the power is turned on.

[0015] The imaging unit may include a storage unit for storing the type of the imaging unit, and the storage unit may store the number of effective pixels of the imaging device in the imaging unit.

Thus, even if the imaging unit is replaced, optimal control according to the number of effective pixels is executed.

In this case, the camera body includes recording means for recording an image, computing means for computing the number of images that can be taken from the effective number of pixels of the image sensor and the free space of the recording means, and the computation result of the computing means. It is desirable to have display means for displaying By calculating the number of shootable images and displaying the calculated number on the display unit, the number of shootable images can be accurately grasped even when the imaging unit is replaced.

If the storage means stores the filter configuration of the imaging unit, appropriate control is executed according to the filter configuration of the imaging unit.

In this case, by providing a change means for changing the interpolation process based on the filter configuration, an appropriate interpolation process based on the filter configuration is executed.

When the defective pixel coordinates of the image pickup section are stored in the storage means, appropriate control is performed in consideration of the defective pixel coordinates, and an appropriate image quality is maintained regardless of the type of the image pickup device. You.

Further, when the storage means stores a drive reference signal for the image sensor, the image sensor is driven by an optimal signal.

When the storage means stores the white balance correction coefficient of the imaging unit, the white balance at the time of flash photography, for example, is kept optimal even when the imaging unit is replaced.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Description of Digital Camera> A digital camera according to this embodiment will be described with reference to FIGS.

The digital camera 1, as shown in FIG.
It is composed of a box-shaped camera body 2 and a rectangular parallelepiped imaging unit 3. The imaging unit 3 is detachably mounted on the right side of the camera body 2 when viewed from the front, and is rotatably mounted in a plane parallel to the right side.

As shown in FIG. 2, the imaging section 3 has a length substantially the same as the length of the camera body 2 in the height direction, and is substantially the same as the width of the camera body 2. The main body 3A has a vertically-long rectangular parallelepiped shape having the following dimensions.
A mounting portion 3B for mounting the device on a protruding portion is provided. The imaging section 3 has a rectangular parallelepiped shape in which the imaging section main body 3A is long in one direction, and can be set along the side surface of the camera main body 2 during storage. It is possible to employ a zoom lens 301 that is long in the axial direction.

The mechanism by which the mounting section 3B mounts the imaging section 3 on the camera body 2 will be described later.

As shown in FIG. 2, a standard macro zoom lens 301 is disposed inside the image pickup section main body 3A.
CC at the right position behind this macro zoom lens 301
An imaging circuit 302 including a D color area sensor 303 is provided. In addition, a dimming circuit 304 including a dimming sensor 305 that receives the reflected light of the flash light from the subject is provided at an appropriate position in the imaging unit 3. Light control sensor 3
Reference numeral 05 is arranged at an appropriate position on the front end surface of the mounting portion 3B.

As shown in FIG. 3, the image pickup section 3 is provided with a lock release lever 307 which enables the image pickup section 3 to be detached from the camera body 2.

On the other hand, as shown in FIGS. 1 to 3, the camera body 2 is, for example, an LCD (Liquid Crystal).
l Display), a mounting portion 17 for the memory card 8, and a connection terminal 13 to which a personal computer is externally connected. The image signal mainly captured by the imaging section 3 is subjected to predetermined signal processing. Later, L
It performs processing such as display on the CD display unit 10, recording on the memory card 8, transfer to a personal computer, and the like.

Next, a mechanism for mounting the image pickup unit 3 on the camera body 2 will be described.

As shown in FIG. 4, on the right side of the camera body 2 when viewed from the front, a connection plate 23 to which the imaging unit 3 is detachably mounted is rotatable in a plane parallel to the right side. It is provided in. The rotation of the connection plate 23 causes the imaging unit 3 attached to the camera body 2 to rotate within a range of approximately ± 90 with respect to the rotation reference position A. The rotation support portion is shown at 500 in FIG.

FIG. 5 shows the mounting surface 308 of the mounting portion 3B.
As shown in the figure, four engagement claws 310a to 31
A rectangular hole 309 provided with 0 d is provided, and the connection plate 23 is fitted into the hole 309 so that the imaging unit 3 is mounted on the camera body 2.

On the mounting surface of the connection plate 23, a connection terminal portion 234 having a plurality of connection terminals is provided, and in the hole 309 of the mounting portion 3B, the connection terminal portion 234 faces the connection terminal portion 234 of the connection plate 23. Terminal part 3 provided with a plurality of connection terminals
When the imaging unit 3 is attached to the camera body 2 via the connection plate 23, the imaging unit 3 and the camera body 2 are electrically connected via the connection terminal units 234 and 334. It has become so.

The connection plate 23 is provided with rectangular recesses 231a and 231b at appropriate positions on both long sides, and is provided on one side of a surface on which the connection terminal portion 234 is not provided (hereinafter, this surface is referred to as a back surface). A groove is formed at each of the corners and at a position continuous with the concave portions 231a and 231b, and the engaging portions 23 with which the engaging claws 310a to 310d of the mounting portion 3B engage respectively.
2a, 232b, 232c, and 232d are provided. In addition, a groove is formed at an appropriate position on the long side where the concave portion 231a is formed on a surface on which the connection terminal portion 234 is provided (hereinafter, this surface is referred to as a surface), and the key member 311 of the mounting portion 3B is formed.
Is provided with an engaging portion 233 into which the is fitted.

The mounting section 3B of the imaging section 3 is mounted on the connection plate 23 of the camera body 2 in the following procedure. That is, first, the mounting surface 308 of the mounting portion 3B is arranged in parallel with the connection plate 23 such that the engagement claws 310c and 310d of the hole 309 face the recesses 231a and 231b of the connection plate 23, respectively. Is pressed against the connection plate 23.
At this time, the engagement claws 310c and 310d are fitted into the recesses 231a and 231b of the connection plate 23, respectively, while the key member 311 is pressed against the surface of the connection plate 23 and the spring 31 is pressed.
2 moves to the unlock position against the urging force of
B is pressed until the back surface of the connection plate 23 becomes the same as the mounting surface 308 of the mounting portion 3B. Thereafter, when the mounting portion 3B is moved to the rear end side (the direction B in FIG. 5), the engaging claws 310a to 310d of the mounting portion 3B engage with the engaging portions 232a to 232d of the connection plate 23, respectively, and the mounting portion 3B is mounted. Portion 3B is connection plate 2
3, the key member 311 is moved to the lock position by the urging force of the spring 312 and fitted into the engagement portion 233, and the state of attachment of the imaging unit 3 to the connection plate 23 is locked.

When the image pickup section 3 is detached from the connection plate 23, the key release member 307 is operated in the direction away from the mounting surface 308 (direction C in FIG. 6) to move the key member 311 to the lock release position (shown by a chain line). Position) and move the key member 3
11 is disengaged from the engaging portion 233, and in this state, the mounting portion 3B is relatively moved with respect to the connection plate 23 in the direction opposite to the direction B in FIG. It is performed by moving in a direction away from the camera.

The imaging unit 3 described above uses an actual focal length of 7 to 21 mm (１ ／ inch size CCD 303), so that it is approximately 38 to 11 in terms of 35 mm film.
5 mm), and a standard zoom lens unit with an FNo of 3.6 (wide side) to 5.6 (tele side) is used. The point is that it is configured to be exchangeable. Therefore, for example, the imaging unit 3 can be replaced with the one shown in FIG.

In FIG. 7, the actual focal length is 5.2 mm.
(Since a 1/2 inch size CCD 303w is used, it is about 28 mm in terms of 35 mm film), FNo1.9
The image pickup unit 3w using the wide-angle lens is mounted.

In FIG. 7, the members corresponding to those in FIG.

Returning to FIG. 1, on the front surface of the camera body 2, a grip 4 is provided at an appropriate position at the left end, and a built-in flash 5 is provided at an appropriate upper portion at the right end. As shown in FIG. 3, on the upper surface of the camera body 2, switches 6 and 7 for frame advance for reproducing a recorded image are provided substantially at the center. The switch 6 is a switch (hereinafter, referred to as an UP switch) for advancing the recorded image in the direction in which the frame number increases (the direction of the photographing order).
The switch 7 is a switch (hereinafter, referred to as a DOWN switch) for advancing the recorded image in the direction of decreasing the frame number. Further, an erasure switch D for erasing an image recorded on the memory card 8 is provided on the left side of the DOWN switch 7 when viewed from the rear side, and a shutter button 9 is provided on the right side of the UP switch 6.

As shown in FIG. 3, on the back of the camera body 2, an LCD display for displaying a captured image on a monitor (corresponding to a view finder) and displaying and reproducing a recorded image is provided substantially at the center of the left end. 10 are provided. Also, L
A compression ratio setting slide switch 12 for switching and setting a compression ratio K of image data recorded on the memory card 8 is provided below the CD display unit 10. A power switch PS and a flash unit are provided above the LCD display unit 10. A mode setting switch 11 (hereinafter sometimes referred to as FL) and the like are arranged. Also, on the side of the camera body 2,
Connection terminal 13 to which a personal computer is externally connected
Is provided.

The digital camera 1 has an "automatic flash mode" in which the built-in flash 5 is automatically fired according to the subject brightness as a mode relating to flash emission, and a "forced" mode in which the built-in flash 5 is forcibly fired regardless of the subject brightness. A flash mode and a flash inhibition mode for inhibiting the flash of the built-in flash 5 are provided. Each time the FL mode setting switch 11 is pressed, each of the automatic flash mode, the forced flash mode, and the flash disabled mode is cyclically switched. Switches to
One of the modes is selected and set.

In the digital camera 1, two kinds of compression ratios K of 1/8 and 1/20 can be selected and set by the compression ratio setting switch 12.
Is slid to the right, a compression ratio K = 1/8 is set, and to the left, a compression ratio K = 1/20 is set. In this embodiment, two types of compression ratios K
Can be selectively set, but three or more types of compression ratios K may be selectively set.

Further, a photographing / reproducing mode setting switch 14 for switching between a "photographing mode" and a "reproducing mode" is provided at the upper right end of the rear surface of the camera body 2.
The photographing mode is a mode in which a photograph is taken, and the playback mode is a mode in which a photographed image recorded in the memory card 8 is
This is a mode for reproducing and displaying on the display unit 10. The shooting / playback mode setting switch 14 also includes a two-contact slide switch. For example, sliding to the right sets the playback mode, and sliding to the left sets the shooting mode.

In the photographing mode, the display unit 10
In the upper area 101, the number of shootable images is displayed.

As shown in FIG. 8, a battery loading chamber 18 and a card loading chamber 17 for the memory card 8 are provided on the bottom surface of the camera body 2, and the loading ports of both loading chambers 16, 17 are clamshell shells. It is closed by a lid 15 of the type. The digital camera 1 according to this embodiment includes:
The drive source is a power supply battery E formed by connecting four AA batteries in series.

Next, the internal configuration of the image pickup section 3 will be described with reference to the block diagram of FIG.

The CCD 303 is a macro zoom lens 30
The light image of the object formed by the step 1 is represented by R (red), G
(Green) and B (blue) color component image signals (signals composed of a signal sequence of pixel signals received by each pixel) are photoelectrically converted and output. The timing generator 331 includes the CCD 30
3 to generate various timing pulses for controlling the driving of the third driving circuit.

The exposure control in the image pickup section 3 is performed by adjusting the exposure amount of the CCD 303, that is, the charge accumulation time of the CCD 303 corresponding to the shutter speed, since the aperture is a fixed stop. If an appropriate shutter speed cannot be set when the subject brightness is low,
By adjusting the level of the image signal output from the CD 303, improper exposure due to insufficient exposure is corrected.
That is, when the luminance is low, the exposure control is performed by combining the shutter speed and the gain adjustment. The level adjustment of the image signal is performed in the gain adjustment of the AGC circuit in the signal processing circuit 313.

The CCD drive circuit 314 controls the CCD 30 based on a signal transmitted from the timing generator 331.
3 is generated. The timing generator 331 generates clock signals such as a timing signal of the A / D converter 321 and a readout control signal (horizontal transfer signal, vertical transfer signal) of a light receiving signal of each pixel. The signal processing circuit 313 performs predetermined analog signal processing on an image signal (analog signal) output from the CCD 303. The signal processing circuit 313 has a CDS (correlated double sampling) circuit and an AGC (auto gain control) circuit. The CDS circuit reduces noise of the image signal, and adjusts the gain of the AGC circuit to adjust the image signal. Level adjustment.

The light control circuit 304 controls the light emission amount of the built-in flash 5 in flash photography to a predetermined light emission amount set by the overall control unit 211. In flash photography, the reflected light of flash light from the subject is received by the light control sensor 305 at the same time as the start of exposure, and when the amount of received light reaches a predetermined light emission amount, the light control circuit 3
An emission stop signal is output from 04 to the FL control circuit 214 via the overall control unit. The FL control circuit 214 forcibly stops light emission of the built-in flash 5 in response to the light emission stop signal, whereby the light emission amount of the built-in flash 5 is controlled to a predetermined light emission amount.

The A / D converter 321 converts each pixel signal of the image signal into a 10-bit digital signal. The A / D converter 321 includes the timing generator 3
Each pixel signal (analog signal) is converted into a 10-bit digital signal based on an A / D conversion clock input from 31.

The EEPROM 341 stores configuration information for specifying the type of the imaging unit 3 as shown in the following table.
As described above, the imaging unit 3 includes another optical system and the CCD 303.
In addition, as described later, the information of the imaging unit 3 is acquired from the EEPROM 341 at the time of replacement, and the control of the camera main unit 2 is switched based on the information. I have.

[0054]

[Table 1] In Table 1, (H) indicates the horizontal direction, and (V) indicates the vertical direction.

The above-described image pickup unit 3 and the camera body 2 described below are provided at a connection terminal 334 of the image pickup unit 3.
Five groups of connection terminals including 334a, 334b, 334c, 334d, and 334e, and 234a, 234b, and 23 provided on the connection terminal 234 of the camera body 2
They are electrically connected by five groups of connection terminals 4c, 234d, and 234e.

Next, the internal configuration of the camera body 2 will be described with reference to the block diagram of FIG.

Here, first, a case where a standard zoom lens 301 is mounted as the imaging unit 3 will be described as an example.

In the camera body 2, a timing control circuit 202 for generating a reference clock, a timing generator 331, and a clock for the A / D converter 321 is provided. The timing control circuit 202 is controlled by the overall control unit 211.

The black level correction circuit 205 corrects the black level of the A / D converted pixel signal (hereinafter referred to as pixel data) to a reference black level using a black reference signal described later. The interpolation processing circuit 206 includes the CCD 30
3 from the raw image data output from pixel 3
This is a circuit that generates 0-bit image data by interpolation processing.

A white balance circuit (hereinafter referred to as a WB circuit) 207 performs level conversion of the pixel data of each of the R, G, and B color components so that the white balance is also adjusted after the γ correction. . WB circuit 20
7 converts the level of the pixel data of each of the R, G, and B color components using the level conversion table input from the overall control unit 211.

The conversion coefficient (gradient of the characteristic) of each color component in the level conversion table is set by the overall control unit 211 for each captured image.

The γ correction circuit 208 corrects the γ characteristics of the pixel data. The γ correction circuit 208 has six types of γ correction tables having different γ characteristics, and performs γ correction of pixel data using a predetermined γ correction table according to a shooting scene and shooting conditions.

The image memory 209 is a memory for storing the pixel data output from the gamma correction circuit 208. The image memory 209 has a storage capacity for one frame. That is, in the image memory 209, the CCD 303
In the case of having pixels in rows and m columns, it has a storage capacity for pixel data of n × m pixels, and each pixel data is stored in a corresponding pixel position.

The VRAM 210 is a buffer memory for image data reproduced and displayed on the LCD display unit 10. VR
The AM 210 has a storage capacity for image data corresponding to the number of pixels of the LCD display unit 10.

In the shooting standby state, each pixel data of the image picked up by the image pickup unit 3 every 1/30 (second) is A
After undergoing predetermined signal processing by the / D converters 321 to γ correction circuit 208, the signals are stored in the image memory 209, transferred to the VRAM 210 via the overall control unit 211, and displayed on the LCD display unit 10. (Live view display). Thus, the photographer can visually recognize the subject image from the image displayed on the LCD display unit 10. Also,
In the reproduction mode, the image read from the memory card 8 is subjected to predetermined signal processing by the overall control unit 211, transferred to the VRAM 210, and reproduced and displayed on the LCD display unit 10.

The card I / F 212 is an interface for writing image data to the memory card 8 and reading image data. Also, communication I / F2
Reference numeral 13 denotes an interface conforming to, for example, the USB standard for externally connecting the personal computer 19 so that communication is possible.

The FL control circuit 214 has a built-in flash 5
This is a circuit for controlling the light emission. The FL control circuit 214
The built-in flash 5 based on the control signal of the overall control unit 211
The presence or absence of light emission, the amount and timing of light emission,
The light emission amount of the built-in flash 5 is controlled based on the light emission stop signal input from the light control circuit 304.

The RTC 219 is a clock circuit for managing the shooting date and time. It is driven by another power source (not shown).

The operation unit 250 includes the above-described UP switch 6, DOWN switch 7, shutter button 9, FL mode setting switch 11, compression ratio setting switch 12, photographing / playback mode setting switch 14, and the like.

The power supply section E is composed of four batteries, and upon receiving a power-off signal from the overall control section 211, both the imaging section 3 and the camera body section 2 are shut down.

The overall control unit 211 is composed of a microcomputer, and controls the driving of each member in the image pickup unit 3 and the camera main unit 2 in an organic manner to control the photographing operation of the digital camera 1 overall. is there.

As shown in FIG. 10, the overall control unit 211 includes a luminance determination unit 211a for setting an exposure control value (shutter speed (SS)) and a shutter speed setting unit 211b.

The brightness determination unit 211a determines the brightness of the subject in the shooting standby state by using an image captured by the CCD 303 every 1/30 (second). That is, the luminance determination unit 211a determines whether the image memory 2
The brightness of the subject is determined using the image data that is renewed and stored in step 09.

The luminance judgment section 211a is provided in the image memory 209.
Is divided into nine blocks, and the luminance data representing each block is calculated using the pixel data of the G (green) color component included in each block.

The shutter speed setting unit 211b determines the shutter speed (the integration time of the CCD 303) based on the result of the brightness determination of the subject by the brightness determination unit 211a.
Is set. Shutter speed setting unit 21
1b has a table of shutter speed SS.

The shutter speed SS is initially set to 1/128 (second) when the camera is started, and in a shooting standby state, the shutter speed setting unit 211b initializes the shutter speed in accordance with the result of the brightness determination by the brightness determination unit 211a. The value is changed and set one step at a time to the high-speed side or the low-speed side.

The overall control unit 211 sets an appropriate shutter speed SS, corrects γ,
In order to perform filtering correction (described later), a scene determination unit 211c that determines four types of shooting scenes of “low-brightness scene”, “medium-brightness normal scene”, “medium-brightness backlight scene”, and “high-brightness scene” is provided. ing. A “low-brightness scene” is a scene that normally requires auxiliary light using a flash, such as indoor shooting or nighttime shooting, and a “medium-brightness normal scene” is illumination light (including natural light and artificial light) for a main subject. ) Is a scene that can be photographed without auxiliary light because the light is normal and the brightness is appropriate. The “medium brightness backlight scene” is a scene in which the overall brightness is appropriate, but the flash light is preferable because the illumination light for the main subject is backlight, and the “high brightness scene” is, for example, a clear sea scene. It is a very bright scene as a whole, like shooting at a ski resort.

Further, the overall control unit 211 determines whether the captured image is a normal photographed image of a landscape, a person, or the like (hereinafter, this type of captured image is referred to as a natural image) or a character drawn on a white board or the like. And an image such as a chart (hereinafter, an image similar to a binary image of this type is referred to as a character image).

The image judging section 211e includes an image memory 209
A histogram of the luminance data at each pixel position is created based on the pixel data constituting the captured image stored in the storage device, and the content of the captured image is determined based on the histogram. In general, a histogram of luminance data of a captured image is a so-called one-peak distribution having a single peak value with a small bias in the luminance distribution in the case of a natural image. In the case of a character image, a bias in the luminance distribution is observed in each of a white background portion and a black character portion.
Mountain distribution. Therefore, the image determination unit 211e determines whether the captured image is a natural image or not by determining whether the histogram of the brightness data BV (i, j) of the captured image has a one-peak distribution or a two-peak distribution. It is determined whether the image is an image.
Then, this determination result is also stored in the memory 211d.

The overall control unit 211 includes a filter unit 211f for performing a filtering process and a recorded image generating unit 211g for generating a thumbnail image and a compressed image in order to perform the recording process of the photographed image. In order to reproduce the displayed image on the LCD display unit 10,
A reproduction image generation unit 211h that generates a reproduction image is provided.

The filter section 211f corrects the high-frequency component of the image to be recorded by a digital filter to correct the image quality related to the outline. Filter section 211
f is a digital filter for performing standard contour correction for each of the compression ratios K = 1/8 and 1/20, and two types of digital filters for enhancing the contour and the contour for the standard contour correction. A total of five types of digital filters, two types of digital filters to be weakened, are provided.

The recorded image generation unit 211g is provided in the image memory 2
The pixel data is read from 09 and a thumbnail image and a compressed image to be recorded on the memory card 8 are generated. The recording image generation unit 211g reads pixel data for every eight pixels in both the horizontal direction and the vertical direction while scanning from the image memory 209 in the raster scanning direction, and sequentially transfers the pixel data to the memory card 8, thereby obtaining the thumbnail image. Is recorded on the memory card 8 while generating.

The recording image generation unit 211g reads out all pixel data from the image memory 209 and converts these pixel data into JPE data such as two-dimensional DCT transform and Huffman coding.
A predetermined compression process according to the G method is performed to generate image data of a compressed image, and the compressed image data is recorded in the main image area of the memory card 8.

In the photographing mode, when photographing is instructed by the shutter button 9 in the photographing mode, the overall control unit 211 displays the thumbnail image of the image taken into the image memory 209 after the photographing instruction and the compression ratio set by the compression ratio setting switch 12. A compressed image compressed according to the JPEG method by K is generated, and tag information (frame number, exposure value, shutter speed, compression ratio K, shooting date, flash on / off data at the time of shooting, scene information, etc.) , And information on the image determination result) are stored in the memory card 8.

As shown in FIG. 11, 40 frames of images can be recorded at a compression ratio of 1/20 of the image recorded by the digital camera 1, and each of the frames 81 to 85 is compressed in the JPEG format with the tag portion. High-resolution image data (6
40 × 480 pixels) and image data for thumbnail display (80 × 60 pixels) are recorded. In each frame unit,
For example, it can be handled as an image file in EXIF format.

<Control of Camera Body Unit 2 According to Imaging Unit 3> Next, control of the overall control unit 211 according to the imaging unit 3 will be described with reference to the flowchart of FIG.

When the camera body 2 is started by pressing the power switch PS, the EEP of the imaging unit 3 is started in S10.
The information shown in Table 1 is acquired with reference to the ROM 341.

In S 20, the image data size per frame is calculated from the data of the number of effective pixels shown in item (3) of Table 1, and the necessary memory capacity as the image memory 209 is secured. In S30, the display of the number of recordable images is switched (S30).

The number of recordable images is obtained by displaying the remaining capacity of the currently inserted memory card 8 and then calculated according to the following equation.

Int (remaining capacity of memory card 8 /
((Effective pixel number H × effective pixel number V × 24/8) × (set compression ratio)) Int () is a function that returns an integer not exceeding the value in the argument. As a result, even if the imaging unit 3 is replaced with another type, an appropriate remaining number is always displayed.

Next, in S40, the thinning rate in the thinning processing at the time of transfer from the image memory 209 to the VRAM 210 in the overall control unit 211 is switched based on the data of the number of effective pixels shown in item (3) of Table 1.

The thinning-out ratio is expressed by the number of effective pixels V / the number of effective pixels H
> Number of vertical pixels of LCD display unit 10 / LCD display unit 10
When the number of vertical pixels of the LCD display unit 10 / the number of effective pixels V The number of effective pixels V / the number of effective pixels H ≦ the number of vertical pixels of the LCD display unit 10 / the number of horizontal pixels of the LCD display unit 10 The number of horizontal pixels / the number of effective pixels H of the LCD display unit 10 is determined. Thus, even when the imaging unit 3 is replaced, the entire photographing screen is always displayed on the LCD display unit 10.

In S50, (1) the type of filter,
(2) The content of the interpolation processing performed by the interpolation processing circuit 206 is set based on the defective pixel information.

(1) Type of Filter The data and the contents stored at each address store the filter configuration (type of CCD) as shown in Table 2, and thereby the interpolation processing circuit 206 Switch processing contents.

[0095]

[Table 2] In the interpolation process of R, G, B, since each pixel has only one color information of R, G, B, the R, G, B of each pixel is obtained by linear interpolation using peripheral pixel data. To generate a value. Also, from Y, M, C to R, G,
In the interpolation processing for B, the following processing is performed. In the CCD 303 having a complementary color filter, the filter arrangement is as shown in FIG.
e, and Mg, the color information of each pixel is obtained by linear interpolation using peripheral pixel data.
Generate the values of y, Ye, Mg, and G. After that, the values of R and B are obtained by the following equation, and color conversion into R, G and B is performed.

B = (Cy-Ye + Mg) / 2, R = (−
Cy + Ye + Mg) / 2 (2) Defective pixel information processing using defective pixel information The coordinates (Xi, Yi) of the defective pixel are recorded, and when the image data from each pixel is read, the address of the address corresponding to the defective pixel is read. The data is not used as image data, but outputs the average value of the four pixels above and below the defective pixel as the value of the defective pixel. With these processes, any CCD
Even if the imaging unit 3 adopting the above is mounted, it is possible to display and record an image without deteriorating an appropriate color tone and image quality.

In S60, the timing for controlling the reading of image data from the CCD 303 is set. The overall control unit 211 of the camera body 2 obtains the data shown in the item (4) in Table 1 from the EEPROM 341. That is, effective pixel start position (H) Esth, (V) Estv black reference pixel number (H) Bh, (V) Bv black reference pixel start position (H) Bsth, (V) Bstv horizontal synchronization signal cycle Th, vertical synchronization Each data of the signal period Tv (CCD drive reference signal) is acquired, and FIG.
The image data is taken into the camera body 2 at the timing shown in FIG.

In FIG. 14, CLK represents a reference clock. One cycle of the reference clock corresponds to reading of one pixel of the CCD 303. At the timing to when the vertical synchronization signal Vd becomes L level, reading of image data for one frame is started. 1 from the reference clock CLK
A horizontal synchronization signal HD is generated for each horizontal period Th, and a vertical synchronization signal VD is generated from the horizontal synchronization signal HD in one vertical period Tv. The horizontal synchronization signal HD corresponds to reading of one line of the CCD 303. From timing to B
After the stv line, a black reference signal having a width Bv is output.
After stv, an effective pixel signal is output. This is repeated for one vertical cycle.

More specifically, when one line of the effective image signal is shown, the timing tl at which the level of the horizontal synchronizing signal HD becomes L level is a reference for a specific one line.
A black reference signal for h pixels is output, and the timing tl
, An effective image signal for Ph pixels is output after an Eth clock. Thus, the image is properly displayed and recorded even if the imaging unit 3 using any CCD 303 is mounted.

In S70, white balance is set at the time of flash photography.

In the white balance correction circuit 207, the white balance correction values (coefficients) R and B shown in item (5) of Table 1 acquired in S10 are stored, and the white balance correction values are applied to the R data at the time of flash photography. The value R is multiplied, and the data obtained by multiplying the B data by the white balance correction value B is output.

As an example, when the color temperature of the flash 5 of the camera body 2 is below 5000 K and the spectral sensitivity characteristic of the CCD 303 is a solid line in FIG. 15, the white balance correction value R = 1.5 and the white balance correction value Value B = 1.
8 is optimal, and the CCD 30
When the spectral sensitivity characteristic of No. 3 is as shown by the dotted line in FIG.
The white balance correction value R = 2.0 and the white balance correction value B = 1.8 are optimal. Therefore, flash 5
The correction value corresponding to the color temperature of the
341 and this is acquired in S10, and S70
By performing the multiplication process of the coefficient at the time of the actual flash photography and recording it, even if the imaging unit 3 is replaced,
The white balance during flash photography can always be optimized.

In S80 and S90, the specifications (see FIG. 16) of the image pickup unit 3 attached at the time of power activation are displayed on the LCD display unit 10 for only 3 seconds.

The display time can be set arbitrarily, and the display of the specifications of the imaging section 3 may be appropriately performed by operating a switch. This is S10
The specifications of the lens of the imaging unit 3 shown in item (7) of Table 1, the type of filter shown in item (1) of Table 1, and the size of the imaging device shown in item (6) of Table 1 obtained in step (1). To be displayed.

When the taking lens 301 is a single focus lens, the lens focal length (wide end) is 0, and display is performed using the value of the lens focal length (tele end).

In S100, processing according to the above-described shooting mode and reproduction mode is performed. If it is detected in S101 that the imaging unit 3 has been removed, the power is turned off from the overall control unit 211 to the power supply unit E in S102. A signal is output, and as a result, both the camera body 2 and the imaging unit 3 are shut down. At the time of replacement of the imaging unit 3, when the imaging unit 3 is removed and another imaging unit is attached, the camera main unit 2 is controlled in accordance with the procedure shown in FIG.

In the above embodiment, the imaging unit 3
Although (3w) is described as being detachably connected to the camera body 2 via the connection plate 23, a configuration in which the imaging unit 3 (3w) is detachably connected to the camera body 2 via a cable is also possible. is there.

[0108]

According to the first aspect of the present invention, the image pickup unit having the image pickup lens and the image pickup element can be exchanged with another type for the camera body, and the image pickup suitable for the purpose of photographing can be performed. If you select an imaging unit with a lens,
The optimum image pickup device corresponding to the above-mentioned photographing lens is automatically set. That is, it is possible to select an optimal pair of a photographing lens and an image pickup device that suits the purpose, and it becomes a very convenient and convenient digital camera.

According to the second aspect of the present invention, in addition to the above effects, the type of the imaging unit is detected and the camera main unit is controlled in accordance with the detection. Can be performed.

According to the third aspect of the present invention, since the camera body detects the type of the imaging unit and displays it on the display means, the type of the mounted imaging unit can be grasped at a glance. .

According to the fourth aspect of the present invention, it is possible to immediately know the type of the imaging unit at the same time when the power is turned on.

According to the fifth aspect of the present invention, the effective number of pixels of the image pickup device is stored in the storage means of the image pickup section. Therefore, even if the image pickup section is replaced, optimal control according to the effective pixel number is performed. Can be executed, for example, it is possible to perform a process of always displaying the entire shooting screen even when the imaging unit is replaced.

According to the sixth aspect of the present invention, the number of images that can be photographed can be calculated and displayed on the display means, so that the number of images that can be photographed can be accurately grasped even when the imaging unit is replaced.

According to the seventh aspect of the invention, it is possible to execute appropriate control according to the filter configuration of the imaging section stored in the storage means.

According to the eighth aspect of the present invention, since the interpolation processing is changed based on the filter configuration, it is possible to execute an appropriate interpolation processing based on the filter configuration.

According to the ninth aspect of the present invention, appropriate control is performed in consideration of the defective pixel coordinates of the image pickup unit stored in the storage means, and appropriate image quality is maintained regardless of the type of image pickup device. Can be.

According to the tenth aspect, the image pickup device can be optimized according to the drive reference signal of the image pickup device stored in the storage means.

According to the tenth aspect of the present invention, even if the imaging unit is replaced by an appropriate control corresponding to the white balance correction coefficient of the imaging unit stored in the storage unit, for example, the white balance at the time of flash photography is obtained. Can be kept optimal.

[Brief description of the drawings]

FIG. 1 is a front view of a digital camera according to an embodiment of the present invention.

FIG. 2 is a front equivalent view showing a configuration of an imaging unit in the digital camera.

FIG. 3 is a rear view of the digital camera.

FIG. 4 is a perspective view showing a connection plate for an imaging unit in the camera body of the digital camera.

FIG. 5 is a perspective view showing the mounting structure of the imaging unit to the imaging unit connection plate.

FIG. 6 is a cross-sectional view showing a mounting lock mechanism of the imaging unit with respect to the connection plate.

FIG. 7 is a front equivalent view showing the configuration of another type of image pickup unit similarly attached to the digital camera.

FIG. 8 is a bottom view of the digital camera.

FIG. 9 is a block diagram showing a control system of the digital camera.

FIG. 10 is a block diagram showing a configuration of an overall control unit in the block diagram of FIG. 9;

FIG. 11 is an explanatory diagram showing a storage structure of an image in a memory card.

FIG. 12 is a flowchart illustrating control of an overall control unit according to an imaging unit.

FIG. 13 is a diagram illustrating a filter arrangement state in an image sensor having a complementary color filter.

FIG. 14 is a timing chart of a festival for taking image data into the camera body.

FIG. 15 is a diagram illustrating spectral sensitivity characteristics of an image sensor when a flash is emitted.

FIG. 16 is an explanatory diagram of a display example of specifications of an imaging unit.

[Explanation of symbols]

 1 ··· Digital camera 2 · · · Camera body 3, 3w · · · · · imaging unit 8 · · · ······· Memory card (recording means) 10 ··· Display unit (display means) 211 ········ General control unit 205 ··· ········ Black level correction circuit 206 ······ Interpolation processing circuit 207 ········ WB circuit 208 ······· γ Correction circuit 301, 301w... Photographing lens 303, 303w... Image sensor 341. Reference signal R, B ... White balance correction coefficient PS Power switch

Continued on front page F term (reference) 5C022 AA13 AB15 AB17 AB20 AB66 AC01 AC33 AC42 AC51 AC75 AC78 5C052 AA17 GA02 GA09 GC05 GC08 GD02 GD03 GD10 GE04 GE08 5C053 FA08 FA27 GA11 GB21 HA08 KA04 KA18 KA24 KA25 LA01 LA06 LA11

Claims (11)

[Claims] An imaging unit having an imaging lens and an imaging device that photoelectrically converts a subject image formed by the imaging lens, and a camera body having an image processing unit that performs image processing of an electric signal from the imaging device. A digital camera in which the imaging unit is detachably attached to the camera main unit, wherein a plurality of different imaging units are configured to be exchangeably mountable to the camera main unit. camera. 2. The camera main body unit includes: a detecting unit configured to detect a type of the image capturing unit;
The digital camera according to claim 1, further comprising control means for controlling the camera body. 3. The digital camera according to claim 1, wherein the camera body includes a detecting unit for detecting a type of the imaging unit, and a displaying unit for displaying a detection result of the detecting unit. 4. The image pickup section includes storage means for storing a type of the image pickup section, while the camera body section obtains information on the image pickup section from the storage means when the power switch is turned on. The digital camera according to claim 2, further comprising information acquisition means. 5. The digital camera according to claim 2, wherein the imaging unit includes a storage unit that stores a type of the imaging unit, and the storage unit stores the number of effective pixels of an imaging element in the imaging unit. . 6. The camera main body unit includes a recording unit that records an image, a computing unit that computes the number of images that can be shot from the effective number of pixels of the image sensor and the free space of the recording unit, and a computation result of the computing unit. The digital camera according to claim 5, further comprising: a display unit that displays a display. 7. The digital camera according to claim 2, wherein the imaging unit includes a storage unit that stores a type of the imaging unit, and the storage unit stores a filter configuration of the imaging unit. 8. The digital camera according to claim 7, further comprising a change unit that changes an interpolation process based on a filter configuration of the imaging unit. 9. The digital camera according to claim 2, wherein the imaging unit includes a storage unit that stores a type of the imaging unit, and the storage unit stores defective pixel coordinates of the imaging unit. 10. The digital camera according to claim 2, wherein the imaging unit includes a storage unit that stores a type of the imaging unit, and the storage unit stores a drive reference signal of the imaging unit. 11. The digital camera according to claim 2, wherein the imaging unit includes a storage unit that stores a type of the imaging unit, and a white balance correction coefficient of the imaging unit is stored in the storage unit.