JPH0771204B2 - Electronic viewfinder camera - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a camera with a so-called electronic viewfinder.

The conventional cameras are roughly classified into the most general type of camera that records a captured subject image on a silver salt film by utilizing chemical changes caused by light, and a video signal of the subject image is obtained and electronically recorded. There is also what is called an electronic camera that records magnetically. The latter type of camera includes an electronic still camera that FM-modulates a video signal and records it in the form of an analog signal on a magnetic disk as a recording medium, and a digital camera that converts the video signal into a digital signal and stores it in an image memory. There are still cameras and video cameras that record video signals representing moving images on a magnetic recording medium (such as a magnetic tape).

In any case, in a conventional camera, automatic focus adjustment (focusing) is performed based on the image information at the center position in the viewfinder, so if the desired subject image portion to be focus-adjusted is not in the center, the focus is adjusted. Blurring could occur. Further, since the automatic exposure adjustment is performed based on the light amount information of the entire screen in the viewfinder, only monotonous image pickup is possible. Furthermore, it has been completely impossible to perform desired operations and processing at desired positions (regions, positions) on the image at the time of photographing.

On the other hand, the viewfinder of the camera is roughly classified into one that is guided by deflecting an optical image captured by the imaging optical system using a prism or the like, or the most general optical type that has a separate finder optical system, and a solid state. There is a so-called electronic viewfinder including a display device that displays an image represented by a video signal captured by an electronic image sensor. Some electronic still cameras for recording video signals of a subject image on the above-described magnetic disk have an electronic viewfinder (for example, Japanese Patent Laid-Open No. 57-44374), which simply functions as a monitor function for picked-up images. Nothing more.

SUMMARY OF THE INVENTION According to the present invention, in a camera equipped with an electronic viewfinder, the characteristics of the electronic viewfinder whose position can be designated on the screen can be used to perform focus adjustment or exposure on a desired portion of a subject image. The purpose is to be able to make adjustments and perform other image manipulations.

A camera with an electronic viewfinder according to the present invention is a solid-state electronic image pickup device that outputs a video signal representing a subject image captured by an image pickup optical system, and an image output from the solid-state electronic image pickup device that is a subject image captured by the image pickup optical system. An electronic viewfinder having a display device for displaying a movable position index on the display image while displaying the ball based on a signal, a ball rotatably and vertically movably supported and urged upward, and the ball described above. Shutter release button that also functions as a ball / mouse, consisting of a position detector that detects the rotational position of the ball and a shutter switch that turns on when the ball descends, and the display position of the position index displayed on the viewfinder. A display control means for moving according to the position detected by the position detector,
An adjusting device for adjusting a predetermined image capturing condition, and an image capturing condition for controlling the image capturing condition by the adjusting device based on image information of a portion of the image information represented by the video signal, which is associated with a position designated by the position index. Output from the solid-state electronic image pickup device in response to an ON signal from the shutter switch of the shutter release button for both ball and mouse under the image pickup condition adjusted by the control unit and the image pickup condition control unit. It is characterized by comprising recording means for recording the image signal to be recorded on a recording medium.

It goes without saying that the solid-state electronic image pickup device includes what is called a so-called electronic shutter including a device such as a frame transfer system in addition to a device such as a CCD. The present invention can be applied not only to still image cameras such as the electronic still cameras and digital still cameras described above, but also to video cameras for moving images. Therefore,
Both analog video signals and digitized image data are handled. The imaging conditions to be adjusted include focusing, shutter speed, aperture, white balance and the like.

A subject image is displayed on the electronic viewfinder based on a video signal obtained from the solid-state electronic image sensor. The position index, which is superimposed and displayed on the subject image of the electronic viewfinder, is set to a desired position by the operator using the shutter release button that also serves as a ball / mouse.
In the former three adjustments, a video signal or image data within a predetermined range designated by the above index is extracted from the display image, and is obtained by applying a predetermined process to the extracted video signal or image data. Focus adjustment and exposure adjustment are performed based on the data. white·
In the control related to the balance, color change is performed so that, for example, a predetermined area designated by the position index is eliminated from green. As a result, it is possible to form a region where the desired color is lost on the captured image or video.

According to the present invention, it becomes possible to designate a desired portion of a subject image on the electronic viewfinder and perform focus adjustment, exposure adjustment, color change, etc. on the designated portion, and an image as desired by the operator can be obtained. Can be taken, and the way to freely use the camera will be opened.

In particular, according to the present invention, a shutter release button that also serves as a ball and mouse is provided, and this shutter release button that also serves as a ball and mouse is supported rotatably and vertically, and is urged upward. , It consists of a position detector that detects the rotation position of this ball and a shutter switch that is turned on when the ball descends. Therefore, rotate the ball to move the position index on the screen of the electronic viewfinder. After setting the shooting condition at the position specified by this operation and the position specified by this operation, shutter release for shooting
You can now press the button down with one finger.

Description of Embodiments Embodiments relating to focus adjustment and exposure adjustment in a digital electronic still camera will be described below in detail.

FIG. 1 shows the back side of a digital electronic still camera. The right side portion of the camera body 1 is a grip portion 2. A ball mouse / shutter release button 4 for inputting position information is provided on the upper end of the grip portion 2.
An electronic viewfinder 3 is provided on the upper rear surface of the camera body 1. The electronic viewfinder 3 is composed of a display device such as a liquid crystal display device and is grasped by an image pickup optical system (reference numeral 11 in FIG. 3) provided on the front side of the camera body 1 and an image sensor (CCD or the like). Of the subject imaged by the solid-state electronic image pickup device) (reference numeral 14 in FIG. 3).

As shown in FIG. 2, the electronic viewfinder 3 displays a cursor (position index) PV in addition to the subject image.
If the display surface of the electronic viewfinder 3 is an XY coordinate plane, the cursor PV can be moved to any position within this plane. The position information input ball mouse / shutter release button 4 is used to move the position of the cursor PV, and the X and Y coordinates of the cursor PV can be changed by rotating the ball mouse with a finger. In a subject image, automatic focus adjustment (focusing) and automatic exposure adjustment (adjustment of aperture and shutter speed) described later are performed for a predetermined range centered on the position of the cursor PV.

Therefore, the operator of this camera holds the grip portion 2 with his / her hand and rotates the ball mouse of the button 4 with one finger to position the cursor PV at a desired position, and then pushes the button.
It is possible to capture a subject image in which the portion of the cursor PV is focused and the exposure is adjusted.

However, only one of the focus adjustment and the exposure adjustment may be performed. Alternatively, two cursors, one for the focus adjustment position designation and one for the exposure adjustment, are displayed on the electronic viewfinder, and the mode is switched to adjust the positions of these cursors with one ball 4 or two balls. May be.

FIG. 3 shows an outline of the electrical construction of the digital electronic still camera, and also shows a removable memory cartridge.

Memory cartridge 5 for shooting with a digital electronic still camera, captured image data, recorded codes, etc.
Transfer, focus adjustment, exposure adjustment and other processing
It is controlled by the controller 10. The main controller 10 is composed of a CPU, a ROM storing its execution program, a RAM for storing necessary data, and the like.

The subject image is an image pickup optical system 11, an aperture stop 12, and an open shutter 13.
Image on the image sensor 14 through the image sensor
The video signal is output from 14. This video signal is then subjected to necessary signal processing such as amplification, gain adjustment and color adjustment in the signal processing circuit 15, and then converted into a digital signal in the A / D conversion circuit 16. This digital signal is further processed by the signal processing circuit.
In 17, necessary processing such as separation into color components was added,
It is given to the image memory 31 as image data and stored. The image memory 31 should have a capacity capable of storing at least one frame of image data.

The output image data signal of the signal processing circuit 17 is the D / A conversion circuit 33.
Is converted into an analog signal by the display control circuit 34 and is used for displaying a subject image on the electronic viewfinder 3. The image data stored in the image memory 31 may be read out and displayed on the electronic viewfinder 3. However, the output analog signal of the signal processing circuit 15 may be subjected to predetermined processing for display and directly input to the display control circuit 34.

The ball mouse / shutter release button 4 includes an X position detector 41, a Y position detector 42 and a shutter switch 43. The X position signal, the Y position signal and the shutter switch signal of the cursor PV are supplied to the main controller 10 Given to. On the one hand, the main controller 10 gives the X position and Y position signals to the display control circuit 34 to control the display position of the cursor PV in the electronic viewfinder 3, and on the other hand, the X position and Y position signals are sent to the memory controller. Give to 32.

The memory controller 32 controls writing of image data to the image memory 31 or reading of the image data from the memory 31. When the X position and Y position signals are given, the memory controller 32 sets a predetermined position centered on the position on the subject image designated by the X position and Y position signals in the image data stored in the image memory 31. Image data within the range (either circular or square) can be read, auto focus and exposure (A
F, AE) Give to controller 20.

The AF / AE controller 20 creates data for focus adjustment and data for exposure adjustment using the given image data, and based on these data, the focusing drive device 2l, the aperture drive device 22 and the shutter drive device. Control 23. These drive devices 21-23 are known per se.

Data for automatic focus adjustment is obtained, for example, by contrast extraction and cumulative calculation for image data. The contrast extraction processing is, for example, a difference calculation performed on the image data read from the image memory 31. The difference calculation of x _n as the image data X _n = | is given by _{1 | x n-1 -2x n} + x n + 1.

The cumulative calculation processing is to integrate the calculation result X _n created in this way within the above-mentioned predetermined range on the screen. This integral is expressed by the following equation.

Here, n represents a predetermined number of pixels.

When the object image is focused most appropriately, the contrast on the screen appears most clearly. The contrast is expressed by a differential value (difference calculation) of image data. The sharpest contrast can be understood as the maximum sum of the differential values in the predetermined range of the screen. Therefore, it can be said that the focusing is optimum when the above integrated value shows the maximum value. controller
Reference numeral 20 controls the driving device 21 so as to maximize the above-mentioned integrated value and adjusts the focus.

There are the following methods for exposure adjustment using image data. One of them is to store a table (program diagram) in which the optimum aperture value and the optimum shutter speed are predetermined for the illuminance in the RAM or ROM in the controller 20, and use the illuminance detected based on the image data as a key. The optimum aperture value and the optimum shutter speed are read from this table. The other is the controller 20
A calculation formula for obtaining the optimum aperture value and the optimum shutter speed is incorporated in the CPU program, and the detected aperture value is substituted into this calculation formula to obtain the optimum aperture value and the optimum shutter speed. At this time, generally, the optimum aperture value is first obtained by the detected illuminance, and then the shutter speed is calculated using the obtained aperture value.

In this exposure adjustment, the average illuminance represented by the image data in the predetermined storage area range read from the image memory 31 is calculated. This average illuminance corresponds to the above detected illuminance. The controller 20 controls the diaphragm driving device 22 so that the calculated diaphragm value is obtained. Then, in response to a signal given from the main controller 10 when the shutter switch 43 is turned on, the shutter drive device 23 is controlled so that the shutter speed has already been calculated.

In FIG. 3, the diaphragm 12 and the shutter 13 are shown as separate parts, but it goes without saying that a diaphragm / shutter can also be used.

Under the control of the main controller 10, the timing control circuit 18 reads out video signals from the image sensor 14, performs various signal processing, A / D conversion, writes image data to the image memory 31, writes image data from the image memory 31. Image data of
The timing of D / A conversion and the like for display on the electronic viewfinder 3 is controlled. Image sensor 14
The video signal is read out at a constant time interval.
Therefore, writing of one frame of image data into the image memory 31 and displaying on the electronic viewfinder 3 are also repeated at fixed time intervals, and the image data in the image memory 31 and the display image on the electronic viewfinder 3 are It is updated at the above fixed time intervals. The display control of the cursor PV in the electronic viewfinder 3, the automatic focus, the exposure adjustment, and the timing of the photographing process by pressing the shutter relays button will be described later.

When mounted on a digital electronic still camera, the memory cartridge 5 is electrically connected by the connector 7 to the above circuits in the camera through various buses and lines. The connector 7 includes a connector provided on the camera side and a large number of terminals provided on the cartridge 5.

The image memory 6 is built in the memory cartridge 5. The image memory 6 has a capacity capable of storing image data for a plurality of photographed frames.

In FIG. 3, a data bus for image data is mainly shown, and an address bus and a control line are not shown. The image memory 6 in the memory cartridge 5 is directly accessed by the main controller 10. The area in the image memory 6 where the image data for one frame taken is to be stored is an address (not shown).
Specified by an address signal provided by controller 10 over the bus.

FIG. 4 and FIG. 5 show an example of a specific configuration of the position information input ball mouse / shutter release button 4 described above.

With reference to these figures, the ball 44 for turning on the switch 43 by the operator rotating the finger with his / her finger to input the X and Y axis positions and pushing the ball 43 is the ball 73, the rolls 51, 52 and the auxiliary balls. It is supported by rollers 45 so as to be rotatable and vertically movable.

A support cylinder 70 is fixed to the frame or the like of the camera body 1. The support cylinder 70 has an inwardly facing flange 71 at its upper end and lower part, and the flange 71 has a center hole. A rod 72 is vertically movably inserted in the center hole. The rod 72 also has an outwardly facing flange 74 on the upper side, and this flange 74 and the lower flange of the support cylinder 70.
A push spring 75 for urging the rod 72 upward is provided between the push spring 75 and 71. The upper limit position of the rod 72 is determined by the flange 74 hitting the upper flange 71 of the support cylinder 70. A push button / shutter switch 43 is provided directly below the rod 72. The small ball 73 is rotatably received on the upper end of the rod 72. The rod is urged by the spring 75.
The load of the ball 44 is received through the ball 72 and the ball 73.

Therefore, by pushing the ball 44 downward against the force of the spring 75, the rod 72 descends and the lower end thereof turns on the switch 43.

Roll 51 for X-axis position detection and roll 61 for Y-axis position detection
Is in contact with the spherical surface of the upper hemisphere above the center of the ball 44, which is held in the upper limit position by the force of the spring 75. These rolls 51 and 61 are orthogonal to each other. Roll 51,6
1 is preferably formed of a member having a large frictional force, or the peripheral surface is coated with a material having a large frictional coefficient.

The X position detector 41 will be described. The roll 51 is rotatably received by bearings 52 at both ends thereof. On the other hand, a photo sensor including a slit plate 56 in which a large number of slits are radially formed and rotatably supported, and a projector and a light receiver provided with the slit plate 56 interposed therebetween.
A rotary encoder composed of 57 and 57 is provided. Gear 53 provided coaxially with roll 51, intermediate gear 5
The rotation of the roll 51 is transmitted to the slit plate 56 via a gear 55 provided coaxially with the slit plate 56. roll
The bearing 52 of 51, the bearing of the intermediate gear 54, the bearing of the slit plate 56 and the photo sensor are fixed to the camera body 1 by a supporting member (not shown).

Therefore, when the ball 44 is rotated in the direction (X-axis direction) orthogonal to the axis of the roll 51, the roll 51 rotates and the photo sensor 57 outputs a pulse signal. The number of pulses output from the photo sensor 57 represents the rotation angle of the ball 44 in the above direction. The above rotary encoder also outputs a signal representing the forward and reverse directions (this is represented, for example, by the phase relationship of the two series of pulse signals).

The Y position detector 42 has the same configuration as the X position detector 41. For reference, reference numeral 62 is a bearing of the roll 61, 63 is a gear coaxial with the roll 61, 64 is an intermediate gear, 66 is a slit plate, 65 is a gear coaxial with the slit plate 66, and 67 is a photo sensor. Is.

Since the Y-axis roll 61 and the X-axis roll 51 are arranged at a right angle in the horizontal plane, the photo sensor 67 outputs a pulse corresponding to the rotation amount when the ball 44 rotates in the Y-axis direction. It

The auxiliary roller 45 is rotatably provided at a position opposite to the rolls 51 and 61. The bearing of this roller 45 is also the camera body 1
It is fixed to.

6 and 7 show another specific example of the ball mouse / shutter button for inputting position information. The same parts as those shown in FIGS. 4 and 5 are designated by the same reference numerals, and the description thereof will be omitted.

A support plate 80 is horizontally attached and fixed to the upper end of the rod 72. The bearing 52 of the roll 51 and the roll 6 are attached to the support plate 80.
1 bearing 62, photo sensor 57, 67, auxiliary roller 45 bearing 46
Is fixed. The total load of all these components is a spring
Supported by 75.

The rolls 51 and 61 and the auxiliary roller 45 are in contact with the spherical surface of the lower hemisphere below the center of the ball 44. In order to prevent the ball 44 from jumping out, a hole smaller than the diameter of the ball 44 is formed in the camera body 1 (the peripheral edge thereof is indicated by reference numeral 81), and a portion above the center of the ball 44 is formed from this hole. It projects to the outside.

The input means for designating the position of the cursor PV is not only the ball mouse described above, but also a push button that moves the cursor PV in a fixed pitch in the X and Y axis directions by one pushing operation or moves a distance according to the pushing time.・ Switch, X, Y
It can also be realized by a slide switch that moves in the axial direction to input position information and a numeric keypad that inputs position information numerically.

Finally, the display position control of the cursor, the relationship between the display position control and the focus, the exposure adjustment process, and the photographing process will be described.

The main controller 10 is provided with registers X and Y for storing the X and Y positions of the cursor PV on the screen of the electronic viewfinder 3, respectively.

When the power is turned on, data representing the coordinates of the center position of the screen of the electronic viewfinder 3 is set in the registers X and Y as initialization processing, and the cursor PV is displayed at the same center position in the electronic viewfinder 3. It

Referring to FIG. 8, when a pulse is output from the X position photo sensor 57, this pulse is given to the main controller 10 as an interrupt signal. The main controller 10 increments or decrements the contents of the register X according to the forward or reverse direction of the pulse (step 101).
The same interrupt process is performed when a pulse is applied from the Y position photo sensor 67 (step 102). Thereafter, the main controller 10 gives new values to the registers X and Y to the display control circuit 34, and the display position of the cursor PV in the electronic viewfinder 3 is changed (step 103). Further, the new values of the registers X and Y are given to the memory controller 32, and the image data corresponding to the new cursor position is read from the memory 31 and given to the AF and AE controller 20, so that the controller 20 has been described above. Focus and exposure adjustment processing is performed (step 104). If an interrupt pulse is given from the photo sensors 57, 67 to the controller 10 during this focus / exposure adjustment process, the focus / exposure adjustment process is stopped and the controller 10 starts a series of interrupts starting from step 101 or 102. Repeat the process. Also, during the processing of steps 101 to 104, the shutter switch
Even if there is an interrupt by 43, the photographing process shown in FIG. 9 described later is not performed.

The photographing process is started by an input interruption from the shutter switch 43 (step 105 in FIG. 9). First shutter 13
Is once closed. After this, the shutter 13 opens for a time corresponding to the shutter speed that has already been determined, and then
The shutter 13 is closed again for a fixed time. Shutter 13
After the A / D conversion processing of the video signal imaged by the image sensor 14 when the is opened It However, once the captured image data is stored in the internal memory 31,
It may be transferred to the cartridge 5. At this time, it is advisable to write the recorded code in a predetermined location of the memory 6 corresponding to the area of the memory 6 in which the image data is stored. The recorded code indicates that regular image data is stored in that area. You may make it write together the code which shows a recording order.

In the above-described embodiment, the image memory 31 is provided in the camera, but this memory 31 should be omitted and the image data taken next to the image memory 6 in the memory cartridge 5 should be written instead. An area or a predetermined area may be used. In this case, the shutter button
The image data stored in this area when 43 is pressed may be directly used as the captured image data.

Before focus and exposure adjustment based on image data, rough focus or exposure adjustment may be performed by known means such as photometric data obtained by a photodiode, and thereafter fine adjustment may be performed based on image data. .

The image sensor is a so-called electronic shutter (frame
In the case of a transfer type CCD, etc.), it goes without saying that the exposure adjustment is performed on this electronic shutter.

In the above embodiment, the data in the predetermined area of the image data once stored in the image memory 31 is read out and the exposure adjustment and the like are performed based on the read out data. However, the analog video signal obtained from the image sensor is used. It is also possible to extract the image signal portion designated by the cursor PV from. In this case, for example, a horizontal counter for counting the horizontal scanning position for each horizontal scanning and a pixel counter for counting each pixel on the specified horizontal scanning line are provided, and the count values of these counters fall within a predetermined range. It is enough to take out the video signal when there is. Alternatively, the video signal could be transmitted through several shift registers connected in series and the video signals could be taken out in parallel from these shift registers. The adjustment and control based on such analog video signals may be applied to the above-mentioned electronic still camera and video camera, for example.

Further, the present invention can be applied to white balance adjustment (change or correction) in addition to exposure and focus adjustment. The white balance is basically adjusted by changing the amplification gain for the R and B video signals. Therefore, the white balance within a range of a circle (or a square or the like) having a predetermined radius centered on a point designated by the cursor on the screen of the electronic viewfinder is intentionally made into a defective state (for example, G component is removed). . This makes it possible to obtain an image in which the predetermined area is decolorized.

[Brief description of drawings]

FIG. 1 is a rear view of a digital electronic still camera, and FIG.
The figure shows an example of the screen of the electronic viewfinder. Fig. 3 is a block diagram showing the electrical structure of the digital electronic still camera and the memory cartridge. Figs. 4 and 5 are balls for inputting position information. Mouse and shutter
FIG. 4 shows a specific example of the release button. FIG. 4 is a plan view, FIG. 5 is a side view showing a partial cross section, and FIGS. 6 and 7 are position information input ball mouse / shutter release.・ Fig. 6 shows another specific example of the button. Fig. 6 is a plan view, Fig. 7 is a side view showing a partial cross section, and Fig. 8 is a procedure for cursor display processing and focus / exposure adjustment processing. A flow chart shown in FIG. 9 is a flow chart showing the photographing process. 1 ... Digital electronic still camera main unit, 3 ... Electronic viewfinder, 4 ... Position information input ball mouse / shutter release button, 5 ... Memory cartridge, 6 ... Image memory, 10 ... Main・ Controller, 11 ...
… Imaging optical system, 12 …… Aperture, 13 …… Shutter, 14 …… Image sensor, 15,17 …… Signal processing circuit, 16 …… A / D conversion circuit, 20 …… Auto focus, exposure controller, 21 ...... Focus adjustment drive, 22 ...... Aperture drive, 23 ...... Shutter drive, 31 ...... Image memory, 32 ...... Memory controller, 34
...... Display control circuit.

Claims (1)

[Claims] 1. A solid-state electronic image pickup device for outputting a video signal representing a subject image captured by an image pickup optical system, and a subject image caught by an image pickup optical system is displayed based on a video signal outputted from the solid state electronic image pickup device. In addition, an electronic viewfinder equipped with a display device that displays a movable position index on the displayed image, a ball that is rotatably and movably supported and that is urged upward, and the rotational position of the ball are detected. The shutter release button that also functions as a ball / mouse and consists of a position detector that operates and a shutter switch that is turned on when the ball descends. The position of the position index displayed on the viewfinder is detected by the position detection device. Display control means for moving in accordance with the position detected by the detector, adjusting device for adjusting a predetermined imaging condition, the video signal Therefore, among the image information represented, the image capturing condition control means for controlling the image capturing condition by the adjusting device based on the image information of the portion related to the position specified by the position index, and the image capturing condition control means are adjusted. Recording means for recording a video signal output from the solid-state electronic image pickup device in a recording medium in response to an ON signal from the shutter switch of the shutter release button that also serves as a ball / mouse under an image pickup condition, Camera with electronic viewfinder equipped with.