JPH05260353A - Camera - Google Patents

Abstract

PURPOSE:To attain zooming photographing with a high magnification while notifying deterioration in picture quality. CONSTITUTION:A lens position of a zoom lens 1a of a photographic optical system 1 is detected by a zoom sensor 5 and calculated by a zoom control section 10 and an optical zoom means obtains a 1st zoom magnification. Furthermore, the signal obtained by an image pickup circuit 3 and an electronic zoom circuit 7 is calculated by the zoom control section 10 to obtain a 2nd zoom magnification by the electronic zoom means. Both the magnifications are displayed separately on a finder of an EVF 9 by means of, e.g. a bar graph.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a camera having optical and electronic zoom functions.

[0002]

2. Description of the Related Art Recently, many cameras have a zoom function for changing the size of an object and taking a picture. This will be described in the case of a video camera. In this type of video camera, the focal length of the zoom optical system for changing the size of a subject image projected on an image pickup device such as a CCD (charge coupled device) is continuously changed to obtain the actual focus of the optical system. A value obtained by dividing the distance by the shortest focal length of the optical system,
That is, the zoom magnification is changed so that the size of the subject image on the image sensor is changed.

In addition to the optical zoom function as described above,
In recent years, there has been a device that realizes an electronic zoom function, and performs electronic zoom in addition to optical zoom, thereby supporting a high zoom ratio. The electronic zoom is, for example, a method for expanding an image by interpolating and interpolating a video signal from a CCD. For example, see Matsushita Electric Industrial Co., Ltd. Technical Report (Vol. 37, No. 3, p13 to p21). It is explained.

To change the zoom magnification, the user operates a predetermined external switch (zoom switch) for setting the zoom magnification provided on the video camera to move the zoom lens to a position where the predetermined zoom magnification can be obtained. To move. At the same time as this zoom operation, the current zoom position (or focal length) of the lens system on the viewfinder.
JP-A-3-135171 discloses a means for displaying information represented by an angle of view at the maximum focal length as an image.

Further, in the UM-E27 type video camera (made by Hitachi), the zoom magnification is displayed in the viewfinder. Further, in the CCD-TR205 type video camera (manufactured by Sony), a bar display on the viewfinder image indicates which side the zoom optical system is located between the tele end and the wide end. Furthermore, in the NV-S9 type video camera (manufactured by Matsushita), when the electronic zoom means is made to function, the characters "zoom" are displayed on the viewfinder image.

[0006]

By the way, since the electronic zoom means produces pixel information which does not originally exist by interpolation calculation and displays it on the monitor, the image quality is inferior to the zoom operation by the optical zoom means. .. In particular, recently, there have been electronic zooms capable of magnifying up to 8 times, but the zoom magnification by the electronic zooming means, which is generally said to be less prominent in image quality deterioration, is about 1.5 to 2 times. If the magnification is doubled, the image quality will be significantly deteriorated.

Now, in the viewfinder image in the technical means disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-135171 and the UM-E27 type video camera, the product of the zoom magnification by the electronic zoom means and the zoom magnification by the optical zoom means is calculated. It is only recognizable, and it is not possible to know what the zoom ratio is due to the electronic zoom operation that causes the deterioration of image quality. Furthermore,
The viewfinder display of the CCD-TR205 type video camera does not support electronic zoom, but merely displays the zoom position by the optical zoom means on the viewfinder. Furthermore, in the viewfinder display of the NT-S9 type video camera, it is merely a display that the electronic zoom means can be used, and at that time, it is displayed whether or not it is an area where the electronic zoom is actually used. is not.

In this case, unlike the image display by the monitor device, the image display on the viewfinder has a limited number of pixels and image quality. Therefore, even if a high-magnification electronic zoom means is used, the image quality deterioration may be noticed. Absent. Therefore, in the worst case, important image-recording cannot be used because of low image quality.

However, since there is a limit to the zoom magnification only by the optical zoom means in the small photographing optical system, when this is set to, for example, 8 times, an ultrahigh magnification which cannot be realized by only the optical zoom means, For example, the optical zoom means is used to increase the magnification by 8 times, and the electronic zoom means is used to increase the magnification by 8 times.
The fact that a 4x zoom factor is possible is attractive.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a camera capable of high-magnification zooming while being aware of the degree of deterioration of image quality.

[0011]

The camera of the present invention is set by the first recognizing means for recognizing the first zoom magnification set by the optical zoom means and the electronic zoom means. Second recognizing means for recognizing the second zoom magnification, first zoom magnification recognized by the first recognizing means, and second zoom magnification recognizing by the second recognizing means. And a display means for displaying each in a recognizable manner.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of essential parts of a camera showing an embodiment of the present invention. The subject light from the subject 14 passes through the zoom lens 1a of the photographing optical system 1 and forms an image on the light receiving surface of the CCD 2. The electric signal photoelectrically converted by the CCD 2 is subjected to signal processing by the image pickup circuit 3 and sent to a recording circuit (not shown) or the like, and is also supplied to the adder 8 to perform optical and electronic zoom from a zoom control unit 10 described later. Is added to the display signal for displaying the state of, and displayed on the EVF (electronic viewfinder) 9 in the viewfinder.

The zoom control section 10 has a microcomputer therein and controls both the optical zoom operation and the electronic zoom operation of the camera in sequence. The telezoom switch 11 and the wide zoom switch 12 are provided outside the zoom control section 10. ，
Electronic zoom switches 13 are respectively connected. When each of these external switches is operated, the zoom control unit 1
0 transmits and receives signals to and from the optical zoom controller 6. As a result, the optical zoom control unit 6 drives the zoom motor 4 to drive the zoom lens 1a to a desired zoom position based on the optical position information detected by the zoom sensor 5. Further, when the electronic zoom switch 13 is operated, the zoom control unit 10 instructs the electronic zoom circuit 7 to perform electronic zoom in the image pickup circuit 3.

The first recognizing means for recognizing the first zoom magnification set by the optical zoom means is composed of the microcomputer incorporated in the zoom control section 10 and the zoom sensor 5. There is. Further, the second recognizing means for recognizing the second zoom magnification set by the electronic zooming means is composed of a microcomputer incorporated in the zoom control section 10. Further, the first zoom magnification recognized by the first recognition means and the second zoom magnification recognized by the second recognition means.
The display means for displaying the zoom magnifications in a recognizable manner is composed of a functional unit for forming a display signal in the microcomputer built in the zoom control unit 10 and the EVF 9 and the like.

The zoom control operation in the present embodiment thus constructed will be described with reference to the flow chart of FIG. In this flow, it is assumed that the first zoom magnification by the optical zoom means operates up to 8 times and the second zoom magnification by the electronic zoom means operates up to 4 times. In addition, OZ in the flow indicates the first zoom magnification, and EZ indicates the second zoom magnification.
Further, the coefficient n indicates the amount of change in each unit time, that is, the zoom speed, in the optical zoom means and m in the electronic zoom means.

When this flow starts, the tele-zoom switch 11 or the wide-zoom switch 12 is first sent.
It is checked whether or not (see FIG. 1) is operated (step S1), and if the tele-zoom switch is pressed, then it is checked whether or not the electronic zoom switch 13 is pressed (step S2). ). In this case, if the electronic zoom switch is turned on, the electronic zoom area can be used as the zoom magnification OZ, so the first zoom magnification OZ by the optical zoom means is first checked (step S4). If it is 8 or less, Since it suffices to operate only the optical zoom means, the process proceeds to S5. On the other hand, if the electronic zoom switch 13 is off in step S2, it is not necessary to operate the electronic zooming means, and therefore the second zoom magnification EZ is set to 1 (step S3).
Go to 5.

In step S5, a new first zoom magnification OZ is obtained by adding the coefficient n to the first zoom magnification OZ, and this new OZ is compared with 8 (step S).
6). If this exceeds 8, the first zoom magnification OZ
Cannot exceed 8, so this is set to 8 (step S7). On the other hand, if it does not exceed 8, the process proceeds directly to step S8.

Returning to step S4, if the first zoom magnification OZ is equal to 8, the electronic zoom means must be used to obtain a higher zoom magnification, so the second zoom magnification EZ has a coefficient m. To obtain a new second zoom magnification EZ (step S10).
The zoom magnification EZ of is compared with 4 (step S11).
If this exceeds 4, the second zoom magnification EZ cannot exceed 4. Therefore, this is set to 4 (step S12), and if it does not exceed 4, on the other hand, the process directly proceeds to step S8.

In step S8, the zoom drive is performed in accordance with the first zoom magnification OZ and the second zoom magnification EZ, and the drive result is displayed in a zoom mode as described later with reference to FIG. 3 (step S9). To return.

Returning to step S1, if the wide zoom switch 12 (see FIG. 1) is pressed, the process proceeds to step S13 to check whether the electronic zoom switch 13, which is an electronic zoom means, is on or off. By the way, the zoom magnification is defined as a value obtained by dividing the actual focal length in the zoom optical system by the shortest focal length, that is, the focal length at the wide angle, as described in the conventional example. The electronic zoom means should equal 1 regardless of the optical zoom means,
It cannot go below 1.

If the electronic zoom switch 13 is turned on in step S13, the second zoom magnification EZ is compared with 1 (step S14). If this EZ is larger than 1, the coefficient m is subtracted from the second zoom magnification EZ to obtain a new second zoom magnification EZ (step S15), and this is further compared with 1 (step S16). If the new second zoom magnification EZ is smaller than 1, it is forcibly set to 1 (step S17). On the other hand, if it is larger than 1, the process directly proceeds to steps S8 and S9 and returns.

If the electronic zoom switch 13 is off in step S13, the second zoom magnification E is obtained in step S18.
After forcibly setting Z to 1, the above step S1
If the second zoom magnification EZ is equal to 1 in step 4, the process immediately proceeds to steps S19 to S21 to set the first zoom magnification OZ by the optical zoom means.

That is, the coefficient n is subtracted from the first zoom magnification OZ to obtain a new first zoom magnification OZ (step S
19). This new first zoom magnification OZ is compared with 1 (step S20), and if it is smaller than 1, it is set to 1 (step S21), and if it is equal to or larger than 1, immediately the above steps S8 and S9 are performed, respectively. Execute and return.

Next, a display example in the subroutine "zoom display" shown in step S9 will be described with reference to FIG. Also in this FIG. 3, the same precondition as in the case of FIG. 2 above, that is, the first zoom magnification by the optical zoom means is 8 times at maximum, and the second zoom magnification by the electronic zoom means is at maximum 4 times. And the electronic zoom switch is on
It can be turned off. The description will be made assuming that when the zoom magnification is 1 to 8 times, only the optical zoom means is used, and when the zoom magnification is 9 to 32 times, the electronic zoom means is used in addition to the optical zoom means.

FIG. 3 is a diagram showing an example in which the zoom magnification is displayed in the bar display and the digital display respectively. In the case of the bar display, the total length of the bars 21 and 31 is the total zoom magnification of 8 × 4 = 3.
A horizontal line 22 indicating the boundary between the optical zoom means and the electronic zoom means is drawn at a position of approximately 1/4 from the bottom of each bar, that is, at a zoom magnification of 8 times, corresponding to 2. Then, a triangular mark 23 arranged on the right side of the bars 21 and 31 and movable up and down from a wide end (W) corresponding to a zoom magnification of 1 time to a tele end (T) corresponding to a zoom magnification of 32 times displays the zoom magnification. It is marked. On the other hand, in the digital display, numerical display is performed as shown on the right side of the figure.

Even if the electronic zoom switch 13 (see FIG. 1) is turned on, only the optical zoom means operates when the zoom magnification is 1 to 8. Therefore, the triangle mark 23 is below the horizontal line 22 of the bar 21. It moves up and down along the area 21b. On the other hand, the zoom magnification is 9 to 32
In this case, both the optical zoom means and the electronic zoom means are activated, and the triangular mark 23 moves up and down along the area 21a above the horizontal line 22.

On the other hand, when the electronic zoom switch 13 is turned off, only the optical zoom means operates, so the zoom magnification is 1 to 8 times. Therefore, the triangular mark 23 in the bar display cannot move up and down in the area above the horizontal line 22. Therefore, the area 31a above the horizontal line 22 indicating the boundary between the optical zoom means and the electronic zoom means and the lower area 31b are different in color, for example, by the user depending on whether or not they are shaded. It is preferable to make it easy to recognize.

In this case, the second zoom magnification set by the electronic zoom means is the first by the optical zoom means.
If the zoom magnification is 8 times, which is the same as the zoom magnification of, the length of the region 31b below the horizontal line 22 becomes ⅛ of the total length. Therefore, when the electronic zoom switch 13 is turned off and the zoom magnifications 1 to 8 are displayed, the magnification is displayed in a region of 1/8 of the entire length of the bar 31, so that the triangular mark 23 representing the zoom magnification is in the lower region 31b. Even if you move up and down along the line, it will be very difficult to see. So the second bar display
As shown in the example, if a character such as "OPT" is put in the bar 51 to indicate that this bar is a region in which the zoom magnification is variable only by the optical zoom means, the triangle mark 53 Since the vertical movement is enlarged and displayed, it becomes very easy for the user to recognize.

With the bar display, the user can recognize the overall zoom position at a glance, and determine whether the current zoom magnification is due to the optical zoom means or the electronic zoom means. You can

Next, the case of digital display will be described. The electronic zoom switch 13 is turned on and the zoom magnification is 1
In the case of .about.8, assuming that the first zoom magnification by the optical zoom means is 4.times., 4 × 1 = × 4 as shown in the upper part of FIG. When the zoom magnification is 9 to 32, for example, if the first zoom magnification by the optical zoom means is 4 and the second zoom magnification by the electronic zoom means is 3,
As shown in the middle part of the figure, it is displayed as 4 × 3 = × 12. Further, when the electronic zoom switch 13 is turned off and the zoom magnification is 1 to 8, the second zoom magnification by the electronic zoom means is off, so that the first zoom magnification by the optical zoom means is 6, for example. As shown in the lower part of FIG.

6 × OFF = × 6 According to the above digital display, it is possible to recognize at a glance whether the zoom magnification is set by the electronic zoom means or the optical zoom means, and at the same time, the specifics thereof can be recognized. Can recognize numbers.

[0032]

As described above, according to the present invention, the first
Since the first zoom magnification recognized by the recognition means and the second zoom magnification recognized by the second recognition means can be recognized separately on the display means, the user can recognize the degree of deterioration of the image quality. The remarkable effect of being able to perform high-magnification zoom shooting while being conscious is exhibited.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a camera showing an embodiment of the present invention.

FIG. 2 is a flowchart of a zoom control operation in the above embodiment.

FIG. 3 is a subroutine “zoom display” in FIG. 2 above.
FIG.

[Explanation of symbols]

5 ... Zoom sensor (first recognizing means) 9 ... EVF (display means) 10 ... Zoom control section (first recognizing means, second recognizing means, display means)

Claims (1)

[Claims] 1. A first recognition means for recognizing a first zoom magnification set by an optical zoom means, and a second recognition means for recognizing a second zoom magnification set by an electronic zoom means. And a display means for displaying the first zoom magnification recognized by the first recognition means and the second zoom magnification recognized by the second recognition means in a separately recognizable manner. And a camera characterized by.