JP3954191B2 - Electronic camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic camera, and more particularly, to an electronic camera that can record a captured image by converting an object image formed by a photographing optical system into an electric signal by an image sensor.
[0002]
[Prior art]
In an electronic camera having an optical viewfinder configured as an optical system independent of the photographing optical system, it is known that parallax occurs when a subject is observed through the optical viewfinder during macro photography.
[0003]
Therefore, as a means for observing a subject, in addition to the above-described optical viewfinder, an electronic camera provided with an image display device such as an LCD that displays an electronic image formed on an image sensor by a photographing optical system is used for macro photography. In the past, it has been proposed to use this image display device to avoid the occurrence of parallax.
[0004]
In such an electronic camera, when observing a subject using an optical viewfinder, it is not inconvenient to observe the subject even if the photographing optical system is out of focus, but an image display device is used. When observing, if the photographic optical system is out of focus, the observed image will also be out of focus, so the photographic optical system must be in focus at least to some extent. .
[0005]
[Problems to be solved by the invention]
However, in the conventional electronic camera, since the first stage of the release switch composed of the two-stage switch is also used as the focusing switch, focusing is not performed unless it is just before shooting. It was. Corresponding to this, it is possible to provide a dedicated focusing operation means, but in this case, it is necessary to provide a space for arrangement in the electronic camera, or the number of parts increases and the cost increases. This is not a desirable solution because it can be tricky.
[0006]
In addition, if the photographic optical system is equipped with a zoom optical system and has a variable focal length, the in-focus position may shift when zooming is performed. This is not desirable from the viewpoint of increasing current consumption, and is especially so in an electronic camera in which portability is emphasized and a small battery is required to be mounted. Furthermore, if the focusing operation is frequently performed during the zoom operation, there is a problem that the zoom operation speed becomes slow due to the interruption by the focusing operation.
[0007]
In addition, when switching from the normal shooting mode to the macro shooting mode, if the zoom position is arbitrary, that is, for example, the telephoto side remains, the depth of field is extremely shallow when entering the macro shooting mode. It became a photographed image and was not easy to use.
[0008]
The present invention has been made in view of the above circumstances, and an object thereof is to provide an electronic camera that can reduce power consumption without impairing usability.
[0009]
A further object of the present invention is to provide an easy-to-use electronic camera in which the subject image does not become extremely difficult to see when switching from the normal shooting mode to the macro shooting mode.
[0010]
[Means for Solving the Problems]
  In order to achieve the above object, an electronic camera according to a first invention comprises:An imaging optical system having a zoom optical system and a focus optical system, and an image sensor that converts a subject image formed by the imaging optical system into an electrical signal, and the electrical signal converted by the image sensor In an electronic camera capable of recording a photographed image, the photographed image is displayed, and an image display device that can be turned on / off, a zooming operation means for instructing a zoom position change of the photographing optical system, Zoom driving means for moving the zoom optical system in response to an instruction from the zooming operation means, focus driving means for moving the focus optical system, and for viewing a subject image, the photographing optical system Is an optical viewfinder configured as an independent optical system, and an object at the same distance that is changed according to the zoom position of the photographing optical system. Comparison means for comparing a deviation amount between a characteristic curve that is a trajectory formed by connecting each point of the position of the focus optical system for focusing and the current position of the focus optical system with a predetermined value, and the zooming operation If it is detected by the comparing means that the amount of deviation has exceeded a predetermined value while the zoom position is instructed by the means, the movement of the zoom optical system by the zoom driving means is interrupted, and the focus driving means Control means for controlling the movement of the zoom optical system by the zoom driving means to continue the movement of the zoom optical system so that the deviation amount is equal to or less than a predetermined value, and then the photographing mode, Normal shooting mode for shooting subjects that are farther away, and macro shooting mode for shooting subjects that are less than the macro farthest distance And a mode switching operation means for performing an operation for switching to, and when the photographing mode is set to the macro photographing mode, the characteristic curve to be compared by the comparing means is the farthest macro. It is a reference characteristic curve that is a trajectory formed by connecting points of a focus optical system for focusing on a subject at a distance.
[0011]
  In order to achieve the above object, an electronic camera according to a second inventionAn imaging optical system having a zoom optical system and a focus optical system, and an image sensor that converts a subject image formed by the imaging optical system into an electrical signal, and the electrical signal converted by the image sensor In an electronic camera capable of recording a captured image as a zooming operation means for instructing a zoom position change of the photographing optical system, and a zoom driving means for moving the zoom optical system in accordance with an instruction from the zooming operation means, The focus driving means for moving the focus optical system and the position of the focus optical system for focusing on a subject at the same distance, which is changed according to the zoom position of the photographing optical system, are connected. A comparison means for comparing a deviation amount between the characteristic curve, which is a locus of the current locus, and the current position of the focus optical system with a predetermined value, and the zooming operation means. If it is detected by the comparison means that the amount of deviation has exceeded a predetermined value while the zoom position change instruction is received, the movement of the zoom optical system by the zoom drive means is interrupted, and the focus drive means The control unit for controlling the movement of the zoom optical system so that the amount of deviation is less than a predetermined value, and then continuing the movement of the zoom optical system by the zoom driving unit again, and the photographing mode, the macro farthest distance Mode switching operation means for switching between a normal shooting mode for shooting a subject at a farther distance and a macro shooting mode for shooting a subject at a distance less than or equal to the macro farthest distance. And when the photographing mode is set to the macro photographing mode, the characteristic curve to be compared by the comparing means is the macro maximum. Length position of the focus optical system for focusing on the subject in the, characterized in that it is a reference characteristic curve is a trajectory formed by connecting the points of.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 to 5 show an embodiment of the present invention, and FIG. 1 is a block diagram mainly showing an electrical configuration of an electronic camera.
[0017]
As shown in FIG. 1, this electronic camera is connected to a photographic lens system 1 as a photographic optical system having a zoom lens 2 as a zoom optical system and a focus lens 3 as a focus optical system. An imager 11 that is an image pickup device that photoelectrically converts an image of an imaged subject and outputs it as an electrical signal, an image pickup circuit 12 that performs predetermined image processing on the output of the imager 11, and an output of the image pickup circuit 12 as a digital signal An A / D conversion circuit 13 for conversion, a memory 14 for storing the output of the A / D conversion circuit 13, and a D / A conversion circuit 15 for reading the digital image data stored in the memory 14 and converting it into an analog signal An LCD drive circuit 16 that receives the output of the D / A conversion circuit 15 and drives an LCD monitor 17 to be described later, and the LCD drive circuit 16 Digital image data stored in the memory 14 in response to an operation of an LCD monitor 17 serving as an image display device that displays a subject image picked up via the photographing lens system 1 by a motion signal and a release switch 25 described later. On the other hand, when the compressed image data is read from the memory card 19 described later while the compression is performed, the compression / decompression circuit 18 that decompresses the image data, and the image data compressed by the compression / decompression circuit 18 are stored. And a detachable memory card 19.
[0018]
Further, in this electronic camera, the output of the imaging circuit 12 is input to the AE circuit 20 that performs automatic exposure calculation, and the result is input to the system controller 22 and the A / D conversion circuit 13 The output is input to a focusing circuit 21 that performs calculations related to focus adjustment, and the result is also input to the system controller 22.
[0019]
The system controller 22 is a control unit that performs overall control of the electronic camera and also serves as a comparison unit. The system controller 22 controls the zoom motor control circuit 6 that is a zoom drive unit based on an output of a zoom switch 24 described later. The zoom motor 5 is driven and is controlled. The zoom motor 5 drives the zoom cam 4 as zoom drive means, thereby moving the zoom lens 2 in the optical axis direction to change the focal length.
[0020]
Further, the zoom cam 4 is provided with a focus motor 8 serving as a focus drive means via an auxiliary frame 7, and is the same focus drive means driven by the system controller 22 based on the output of the focusing circuit 21. The focus motor control circuit 9 controls the focus motor 8 to adjust the in-focus position by the focus lens 3.
[0021]
The system controller 22 is connected to an operation switch group 23 including a plurality of operation switches. The operation switch group 23 includes a zoom switch 24 which is a zooming operation unit including a tele zoom switch 24T and a wide zoom switch 24W, and A release switch 25, which is a two-stage switch for instructing the recording and recording to the memory card 19, and a mode switching operation means for switching the focal length of the photographing lens system 1 between a normal photographing region and a macro photographing region. A macro changeover switch 26 and an LCD monitor on / off switch 27 for turning on / off the LCD monitor 17 are provided.
[0022]
The electronic camera can further use a battery 34 and an external power source supplied from an external power input terminal 35 as power sources. The battery 34 and the external power input terminal 35 are connected to the switching circuit 32. Thus, which one is used as the power source can be switched. In other words, the type of power source connected to the switching circuit 32 is detected by the detection circuit 31 and input to the system controller 22, and the system controller 22 A power source is selected, and switching is performed by the switching circuit 32 via the detection circuit 31.
[0023]
The power supplied from the switching circuit 32 is converted into an appropriate driving voltage by the DC / DC converter 33 and supplied to each circuit inside the electronic camera.
[0024]
Next, FIG. 2 is a rear view showing the appearance of the electronic camera.
[0025]
The LCD monitor 17 for displaying the state of the subject image formed by the photographing lens system 1 is disposed in the center of the back side of the camera body 41 of the electronic camera. An LCD monitor on / off switch 27 for turning on / off the LCD monitor 17 is disposed, and on the lower side thereof, the focal length is widened opposite to the tele zoom switch 24T for moving the focal length to the tele side. A wide zoom switch 24W for moving to the side is arranged in order.
[0026]
In addition, in the vicinity of the upper left of the LCD monitor 17, the shooting mode of this electronic camera covers a normal shooting mode position (NORMAL) that covers a shooting range of, for example, 80 cm to ∞, and a shooting range of, for example, 20 cm to 80 cm. A macro switch 26 for switching to a macro shooting mode position (MACRO) is provided. The photographing lens system 1 of this electronic camera can continuously cover the subject distance from the shortest 20 cm to the farthest ∞ by moving the focus lens 3. Can take advantage of the fact that shooting at a distance of 80 cm or less is performed less frequently and the time required for focusing can be shortened by limiting the amount of movement of the focus lens 3. It is divided into two parts, a macro imaging area up to 80 cm and a normal imaging area up to 80 cm to ∞.
[0027]
In the vicinity of the upper left of the macro changeover switch 26, an eyepiece 42 is disposed as a part of an optical viewfinder configured as an optical system independent of the photographing lens system 1. This optical viewfinder is also for visually grasping the subject range and composition to be photographed, and has the advantage that the power required for driving is small (or only 0). However, it is provided separately.
[0028]
The release switch 25 is disposed on the right side of the upper surface of the camera body 41 of the electronic camera, for example, at a position where it can be easily pressed with the index finger of the operator.
[0029]
Next, FIG. 3 is a diagram showing changes in the focus lens position when the macro shooting mode is set and zooming is performed, and FIG. 4 is a diagram showing changes in the focus lens position when zooming is performed in the normal shooting mode. FIG. 5 is a flowchart showing the operation of the electronic camera.
[0030]
First, prior to the description of the operation, the vertical and horizontal axes in FIG. 3 and FIG. 4 and some characteristic curves will be described.
[0031]
In these diagrams, the zoom position of the photographing lens system 1 is taken as the horizontal axis, and the position of the focus lens 3 is taken as the vertical axis.
[0032]
The zoom area within the shootable range is from the wide end W to the tele end T.
[0033]
The characteristic curve L0 in these figures shows how the position of the focus lens 3 moves when the zoom operation is performed by driving the zoom cam 4 when the focus lens 3 is set to an infinite position. Is. That is, the focus lens 3 is driven by the focus motor 8 independently of the zoom lens 2, but as described above, the focus lens 3 is related to the zoom cam 4 via the auxiliary frame 7. Therefore, the position moves in the optical axis direction even when only the zoom operation is performed. More specifically, since the cam pin of the auxiliary frame 7 is engaged with the cam groove of the zoom cam 4, the focus lens 3 is also moved in the optical axis direction by the rotation of the zoom cam 4 by the zoom operation.
[0034]
Similarly, a characteristic curve L1 in the figure is a curve when the focus lens 3 is located at a photographing position of 80 cm (macro farthest distance) which is the farthest position in the macro photographing region, and a characteristic curve L2 is the closest position in the macro photographing region. It is a curve when there is the focus lens 3 at the photographing position of 20 cm.
[0035]
Therefore, the movement range of the focus lens 3 when the zoom position is at the telephoto end T is from PT1 to PT2 in the figure, and the movement range of the focus lens 3 when the zoom position is at the wide end W is From PW1 to PW2.
[0036]
When an appropriate focus lens position is set as an initial position and only zooming by the zoom motor 5 is performed from the initial position without driving the focus lens 3 by the focus motor 8, the characteristic curve L0 is parallelized. The focus lens 3 moves on a curve that is moved and superimposed on the initial position.
[0037]
In other words, when the focus lens 3 is on the characteristic curve L0, which is the focus position at infinity, even if zooming is performed, it is still on the characteristic curve L0 and only the zoom position changes. When the focus lens 3 is located at L1 or the characteristic curve L2, if zooming is performed, a deviation corresponding to the amount of zoom change occurs from these characteristic curves.
[0038]
In other words, the characteristic curve is a curve connecting focus lens positions that focus on subject positions at the same distance at each continuously variable zoom position, and when the focus lens 3 is placed at an infinite position. Except for, since the focus position shifts due to zooming, the focus lens 3 must be appropriately moved and corrected to be placed on the characteristic curve.
[0039]
Since there are characteristic curves for each subject distance that can be continuously changed from 20 cm to ∞, there are infinite number of characteristic curves.
[0040]
Next, the operation of the electronic camera will be described along FIG. 5 with reference to FIGS.
[0041]
When this operation starts, it is first determined whether or not the operation of the macro changeover switch 26 has been performed (step S1). Is set to the macro shooting mode (step S2).
[0042]
Next, it is determined whether or not the current zoom position is at the wide end (step S3). If not, the zoom position is moved to the wide end (step S4). This is because the wide end has a deep depth of field and is considered to be most suitable for the initial state in which macro shooting is performed. When the macro shooting mode is switched, the wide end is automatically set to the wide end. By improving the usability, usability has been improved.
[0043]
That is, in the example shown in FIG. 3, it is assumed that the focus lens 3 is at the position indicated by the point Pr in the normal photographing mode, for example. In this state, when the macro changeover switch 26 is operated to switch to the macro photographing mode, the system controller 22 drives the zoom cam 4 by the zoom motor 5 so that the focus lens 3 moves on the dotted line Z0 shown in the figure passing through the point Pr. Move to reach the wide end W.
[0044]
Next, after the zoom position is already at the wide end W in step S3, or after the zoom position is set to the wide end W in step S4, the position of the focus lens 3 is the farthest position in the macro imaging region (that is, In this example, it is determined whether or not the photographing position is 80 cm, that is, whether or not it is on the reference characteristic curve L1 (step S5).
[0045]
Here, when the photographing position is not 80 cm, the focus lens 3 is moved onto the reference characteristic curve (step S6). In the example of FIG. 3, since the point moved from the point Pr to the wide end only by zooming is not on the reference characteristic curve L1, the focus motor 8 is driven and the focus lens 3 is moved by F0 shown in the figure. The process proceeds to a point P0 which is the wide end position on the reference characteristic curve L1. This point P0 is the initial position when the macro photographing mode is set.
[0046]
If the focus lens 3 is already on the reference characteristic curve L1 in step S5 or moved to the reference characteristic curve L1 in step S6, the LCD monitor 17 is turned on. This is because the parallax occurs between the range observed by the optical finder and the shooting range by the shooting lens system 1 in the macro shooting region, so that the LCD monitor 17 can be checked so that an accurate shooting range can be confirmed. It is designed to turn on automatically.
[0047]
By the operations up to step S7, the initialization when the macro shooting mode is set is completed.
[0048]
Next, waiting for the operation of the zoom switch 24 (step S8), when the operation is performed, the zoom movement is started in the instructed zoom direction (step S9). It should be noted that since the zoom lens is at the wide end immediately after the initialization is completed, the only possible zoom movement direction at this time is the tele direction.
[0049]
As described above, since the position of the focus lens 3 deviates from the reference characteristic curve L1 as the zoom moves, this deviation amount is detected and it is determined whether or not the deviation amount is a predetermined value or more (step S10). Only when the predetermined value or more is reached, the focus lens 3 is moved onto the reference characteristic curve L1 (step S11).
[0050]
If the deviation amount is within the predetermined value in step S10 or the movement of the focus lens 3 is completed in step S11, it is determined whether or not the zoom switch 24 remains on (step S12). ) If it is ON, the process returns to step S9 and the above operation is continued.
[0051]
If it is determined in step S12 that the operation of the zoom switch 24 has been completed, a focusing operation is performed (step S13).
[0052]
That is, in the example shown in FIG. 3, when moving from the initial position P0 to the closest photographing position P1 at the tele end, for example, when the tele zoom switch 24T is pressed, the zoom motor 4 is driven by the zoom motor 5. Although zooming is performed in the tele direction, the focus position deviates from the subject position of 80 cm as indicated by the dotted line Z1 according to the zoom. Therefore, when the deviation amount exceeds a predetermined value, it is moved by F1 as shown and returned to the reference characteristic curve L1. Further, if the zooming is continued, it will deviate from the reference characteristic curve L1 again as indicated by the dotted line Z2, so when it exceeds the predetermined value, it is again moved by F2 as shown and returned to the reference characteristic curve L1. Further, as shown by the dotted line Z3, when zooming is continued and the telephoto end is reached, zooming is completed.
[0053]
Next, an operation when moving from the closest shooting position P1 at the telephoto end to a subject at a shooting position P2 of, for example, about 30 cm in the middle zoom position will be described.
[0054]
Since P1 is not on the reference characteristic curve L1, the focus lens 3 is first driven by the focus motor 8 and moved by F4 in the drawing to be put on the reference characteristic curve L1.
[0055]
Next, zooming is performed in the wide direction as indicated by the dotted line Z4 in accordance with the operation of the wide zoom switch 24W. Return to the top. Thereafter, zooming in the wide direction is continued again as indicated by the dotted line Z5. Since the target zoom position is where the wide zoom switch 24W is turned off, the focus lens 3 is driven at that position and F6 And moving to the target position P2 for focusing.
[0056]
Thus, in step S13, when the zoom operation is completed, the focus position of the photographing lens system 1 matches the subject, and the subject image observed by the LCD monitor 17 becomes a focused image.
[0057]
In this way, in the macro shooting mode, the focus lens that moves independently from the zoom lens 2 by first moving to the reference characteristic curve L1 that is the farthest position in the macro shooting area and then performing the zoom operation. 3 can be prevented from interfering with the last lens among the lenses constituting the zoom lens 2.
[0058]
Further, when zooming substantially along the reference characteristic curve L1, the focus lens 3 is driven and moved onto the reference characteristic curve L1 when a deviation of a predetermined value or more occurs, so that the reference characteristic curve L1 is always used. Compared with the case of moving along the characteristic curve L1, the burden due to the focus operation is reduced, so that power consumption can be reduced.
[0059]
In addition, since the characteristic curve L1 which is the farthest position in the macro imaging region is used as the reference characteristic curve, for example, compared to the case where the characteristic curve L2 which is the closest position in the macro imaging region is used as the reference characteristic curve, It is possible to reduce the number of focus operations until reaching.
[0060]
That is, when moving from the point P1 to the point P2, if it is moved so as to substantially follow the characteristic curve L2, the zoom is performed in the wide direction and moved by Z7. Then, after returning to the characteristic curve L0, after moving the zoom to Z8, F8, Z9, F9, and Z10 and zooming, the focus lens 3 is moved by F10 and focusing is performed. In the case of following L1, the operation of returning to the characteristic curve only once in the middle is required, and the operation of returning three times in the middle is required. As described above, by selecting L1 as the reference characteristic curve whose slope of the characteristic curve is the gentlest among the infinite number of characteristic curves that can exist in the macro imaging region, the movement of moving the focus lens 3 is the least. In this way, the power consumption can be reduced to the maximum.
[0061]
Subsequently, if the macro switch 26 is not operated in step S1, the electronic camera is set to the normal shooting mode (step S14).
[0062]
Then, waiting for the operation of the zoom switch 24 (step S15), when the operation is performed, the zoom movement is started in the instructed zoom direction (step S16), and the zoom switch 24 is kept on. Is determined (step S17), and if it is on, the process returns to step S16 to continue the zoom movement.
[0063]
If it is determined in step S17 that the operation of the zoom switch 24 has been completed, it is determined whether or not the LCD monitor 17 is turned on (step S18). A focusing operation is performed (step S19). Thereby, when the zoom operation is finished, the focal position of the photographing lens system 1 matches the subject, and the subject image observed by the LCD monitor 17 becomes a focused image.
[0064]
That is, in the example shown in FIG. 4, when zooming only in the wide direction, for example, on the subject at the same distance from the initial position P4, when the wide zoom switch 24W is pushed, the zoom motor 5 4 is driven and zoom is performed in the wide direction as indicated by Z11, but the focus position deviates from the characteristic curve L3 passing through the point P4 according to the zoom. Therefore, when the LCD monitor 17 is on, when the deviation amount exceeds a predetermined value, the LCD monitor 17 is moved by F11 shown in the figure and returned to the reference characteristic curve L3. Then, zooming in the wide direction is continued again as indicated by Z12, and when the target zoom position is reached, the wide zoom switch 24W is turned off. At that position, the focus lens 3 is driven and moved by F12. The focusing operation is performed to reach the target position P5.
[0065]
If it is determined in step S18 that the LCD monitor 17 is not turned on, it means that observation is performed through the optical viewfinder, and the time point when a release switch 25 (to be described later) is input. In this case, since it is sufficient to perform the focusing operation, the focusing operation is not performed here.
[0066]
That is, in the example shown in FIG. 4, when the zoom is performed from the initial position P4 to the target position P5, the zoom is continued as indicated by Z13 even if the deviation amount exceeds a predetermined value. When the target zoom position is reached, a release switch 25 (to be described later) is waited for, and when it is pressed, focusing is performed as indicated by F13.
[0067]
By performing such an operation, the focus lens 3 is sequentially moved only when necessary in accordance with the state of the LCD monitor 17, so that power consumption can be reduced.
[0068]
Further, when the LCD monitor 17 is on, since the focus lens 3 is moved after waiting for the deviation amount to reach a predetermined value, the subject image to be confirmed by the LCD monitor 17 is too out of focus. The power consumption can be reduced within the range, and the balance between ease of use and power saving is well-sought.
[0069]
In the above description, when the LCD monitor 17 is on, the focus lens 3 is moved when the deviation amount reaches a predetermined value. However, in order to further reduce power consumption, the zoom switch 24 is turned on. During this time, the focus lens 3 is not driven at all, and focusing may be performed when the zoom switch 24 is turned off and there is no zooming instruction. In this case, as compared with the case where the LCD monitor 17 is off, the camera is focused immediately after zooming is completed without waiting for the release switch 25 to be turned on.
[0070]
Thus, when the steps S13 and S19 are completed or when the LCD monitor 17 is off in the step S18, it waits for the first stage of the release switch 25, which is a two-stage switch, to be turned on (step S18). S20) When it is turned on, the focus lens 3 is moved to perform a focusing operation (step S21).
[0071]
Further, automatic exposure adjustment (AE) and automatic white balance adjustment (AWB) are performed (step S22), and the process waits for the second stage of the release switch 25 to be turned on (step S23).
[0072]
When it is detected that the second stage is turned on, the imager 11 captures an image (step S24), the output image is processed by the imaging circuit 12, and the compression / decompression circuit 18 performs compression processing. (Step S25), the data is recorded in the memory card 19 (Step S26), and the process ends.
[0073]
In the above description, the focus lens 3 is moved when the shift amount exceeds a predetermined value both in the case of zooming from the tele side to the wide side and in the case of zooming from the wide side to the tele side. When moving from the wide side to the tele side, the zoom lens 2 and the focus lens 3 do not interfere with each other, so that the movement of the focus lens 3 during zooming may be omitted. According to this, power consumption can be further reduced.
[0074]
As described above, according to such an embodiment, the focusing shift that occurs during zoom movement is corrected after waiting until the shift amount exceeds a predetermined value, thereby reducing power consumption. It is possible to prevent usability from deteriorating.
[0075]
In addition, when the LCD monitor is off, the power consumption can be further reduced because correction is not performed during zoom movement even if focusing deviation occurs.
[0076]
Furthermore, in the macro shooting mode, after moving to the reference characteristic curve that is the farthest position in the macro shooting area, and zooming substantially along the reference characteristic curve, without providing a special mechanism or the like, It is possible to prevent the zoom lens and the focus lens from interfering with each other.
[0077]
Since the characteristic curve with the slowest inclination in the macro shooting area is selected as the reference characteristic curve, the number of movements of the focus lens during the zoom operation is suppressed to a minimum, and the zoom operation can be speeded up. The power consumption can be reduced.
[0078]
On the other hand, when the macro shooting mode is set, the farthest position at the wide end is set as the initial position and is automatically set to this initial position, so it is used because the depth of field is the deepest during macro shooting. It is possible to use the wide end, which is often used, as the starting point of the operation, improving usability.
[0079]
It should be noted that the present invention is not limited to the above-described embodiments, and various modifications and applications can be made without departing from the spirit of the invention.
[0080]
【The invention's effect】
  As explained above,According to the electronic camera of the present invention, since the focus optical system is moved only when the amount of deviation from the characteristic curve becomes a predetermined value or more during zoom movement, the focus optical system is continuously moved. Compared to the case, the power consumption can be reduced and the zoom operation can be speeded up. Also, when the macro shooting mode is set, the zoom operation almost follows the reference characteristic curve corresponding to the farthest macro distance. As a result, it is possible to avoid interference between the zoom optical system and the focus optical system. Furthermore, since the reference characteristic curve has the slowest slope among the characteristic curves that can be taken in the macro shooting mode, it is possible to reduce the number of movements of the focus optical system and to further reduce power consumption. it can.
[Brief description of the drawings]
FIG. 1 is a block diagram mainly showing an electrical configuration of an electronic camera as one embodiment of the present invention.
FIG. 2 is a rear view showing the appearance of the electronic camera of the embodiment.
FIG. 3 is a diagram showing a change in a focus lens position when zooming is performed with the macro shooting mode set in the embodiment.
FIG. 4 is a diagram illustrating a change in a focus lens position when zooming is performed in a normal shooting mode in the embodiment.
FIG. 5 is a flowchart showing the operation of the electronic camera of the embodiment.
[Explanation of symbols]
1 ... Shooting lens system (shooting optical system)
2. Zoom lens (zoom optical system)
3. Focus lens (focus optical system)
4. Zoom cam (zoom drive means)
5. Zoom motor (zoom drive means)
6 ... Zoom motor control circuit (zoom drive means)
8: Focus motor (focus drive means)
9: Focus motor control circuit (focus drive means)
11. Imager (image sensor)
17 ... LCD monitor (image display device)
21 ... Focus circuit
22 ... System controller (control means, comparison means)
24. Zoom switch (zooming operation means)
25. Release switch (release operation means)
26 ... Macro switch (mode switching operation means)
27 ... LCD monitor on / off switch
42 ... Eyepiece (part of optical viewfinder)

Claims (2)

An imaging optical system having a zoom optical system and a focus optical system, and an image sensor that converts a subject image formed by the imaging optical system into an electrical signal, and the electrical signal converted by the image sensor In an electronic camera that can record
An image display device that displays the captured image and can be turned on / off;
Zooming operation means for instructing to change the zoom position of the photographing optical system;
Zoom driving means for moving the zoom optical system in accordance with an instruction from the zooming operation means;
Focus drive means for moving the focus optical system;
An optical viewfinder for visually recognizing a subject image, and configured as an optical system independent of the photographing optical system;
A characteristic curve that is a trajectory connecting the points of the focus optical system for focusing on a subject at the same distance, which is changed according to the zoom position of the photographing optical system, and the current focus optics Comparison means for comparing the position of the system and the amount of deviation with a predetermined value;
If it is detected by the comparison means that the amount of deviation exceeds a predetermined value while the zoom operation means is instructed to change the zoom position, the movement of the zoom optical system by the zoom drive means is interrupted, and the focus Control means for controlling the movement of the zoom optical system by the zoom driving means after that the focus optical system is moved by the driving means so that the deviation amount becomes a predetermined value or less;
To switch the shooting mode between the normal shooting mode for shooting subjects that are farther than the macro farthest distance and the macro shooting mode for shooting subjects that are less than the macro farthest distance Mode switching operation means,
Comprising
When the photographing mode is set to the macro photographing mode, the characteristic curve to be compared by the comparing means is a point of the focus optical system for focusing on the subject at the macro farthest distance. An electronic camera characterized by a reference characteristic curve that is a trajectory formed by connecting the two .   An imaging optical system having a zoom optical system and a focus optical system, and an image sensor that converts a subject image formed by the imaging optical system into an electrical signal, and the electrical signal converted by the image sensor In an electronic camera that can record
  Zooming operation means for instructing to change the zoom position of the photographing optical system;
  Zoom driving means for moving the zoom optical system in accordance with an instruction from the zooming operation means;
  Focus drive means for moving the focus optical system;
  A characteristic curve that is a trajectory connecting the points of the focus optical system for focusing on a subject at the same distance, which is changed according to the zoom position of the photographing optical system, and the current focus optics Comparison means for comparing the position of the system and the amount of deviation with a predetermined value;
  If it is detected by the comparison means that the amount of deviation exceeds a predetermined value while the zoom operation means is instructed to change the zoom position, the movement of the zoom optical system by the zoom drive means is interrupted, and the focus Control means for controlling the movement of the zoom optical system by the zoom driving means after that the focus optical system is moved by the driving means so that the deviation amount becomes a predetermined value or less;
  To switch the shooting mode between the normal shooting mode for shooting subjects that are farther than the macro farthest distance and the macro shooting mode for shooting subjects that are less than the macro farthest distance Mode switching operation means,
  Comprising
  When the photographing mode is set to the macro photographing mode, the characteristic curve to be compared by the comparing means is a focus optical for focusing on the subject at the macro farthest distance. An electronic camera characterized by a reference characteristic curve that is a trajectory formed by connecting points of the system.

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