JP3678205B2 - Digital camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital camera using a zoom focus type imaging lens.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, zoom focus type imaging lenses that perform focal length adjustment (zooming) and focus adjustment (focusing) with a single motor are known. In the zoom focus type imaging lens, the relative position of a plurality of lens groups constituting the imaging lens is changed to change the focal length and the focal position. For this reason, zooming and focusing can be performed with one motor, but the focal length of the lens cannot be continuously changed between the short focal side end and the long focal side end, and a plurality of preset focal lengths can be set. The focal length can only be changed in steps. Such a zoom focus type imaging lens is used in a lens shutter type compact camera or the like in the field of a camera using a silver salt film.
[0003]
On the other hand, in the field of digital cameras, in addition to optical zoom using a zoom lens as an imaging lens, electronic zoom that extracts and enlarges a part of image data obtained by an imaging unit has been put into practical use.
[0004]
[Problems to be solved by the invention]
In order to reduce the size and weight of digital cameras, the above zoom focus imaging lens is adopted, and a part of image data obtained by the imaging unit as a finder is extracted and enlarged, and a display unit such as an LCD (Liquid Crystal Display) It has been proposed to employ an electronic viewfinder that displays on the screen. However, in the case of an imaging lens of the zoom focus method, the focal length can be changed only in steps, so that the size of the image displayed on a monitor screen such as an LCD during zooming does not change smoothly, and the appearance is It had the problem that it was not good.
[0005]
On the other hand, in digital cameras, since the power consumption in the display unit is large, there is also known an optical finder that can suppress power consumption as much as possible by using an electronic viewfinder and an optical viewfinder separately. It has been.
[0006]
By the way, since the finder is for the photographer to set the angle of view of the subject, if the digital camera has a zoom function, the subject image that can be visually recognized by the finder according to the zoom switch operation by the photographer. It is preferred that the size changes continuously. Therefore, in a digital camera equipped with a zoom focus type imaging lens, a zoom finder is adopted as an optical finder, an electronic zoom is adopted for an image displayed on the electronic finder, and an optical finder is selected as the finder. The electronic viewfinder is selected by driving the zoom finder magnification changing lens in accordance with the signal that detected the operation of the zoom switch to continuously change the magnification of the subject optical image viewed from the eyepiece window. In this case, the image enlargement ratio or reduction ratio is set based on a signal that detects the operation of the zoom switch, and the image data obtained by the imaging unit is enlarged or reduced according to the enlargement ratio or reduction ratio and displayed on the display section. To change the subject image continuously (hereinafter referred to as a file by such a display method). Da of electronic zoom finder.) Are preferred.
[0007]
However, when an optical finder consisting of a zoom finder (hereinafter referred to as an optical zoom finder) is adopted in a digital camera equipped with a zoom focus type imaging lens, both the optical lens and the optical finder have a zoom mechanism. If a drive source is provided in the system, it is contrary to the purpose of reducing the size and weight of the camera by adopting a zoom focus type photographing lens.
[0008]
Therefore, it is desirable to make the zoom drive source of the photographing lens and the zoom drive source of the optical zoom finder common, and to reduce the size and weight of the camera as much as possible. Used to obtain a display image of an electronic zoom finder when the image is smoothly changed on the LCD using a zoom focus type photographing lens (the invention proposed by the inventor in Japanese Patent Application No. 13-374417). The zoom operation of the taking lens changes step by step. On the other hand, in order to smoothly (continuously) change the image of the optical viewfinder linked with the zoom of the taking lens, the zoom operation of the taking lens needs to change continuously. Since the operation of the zoom drive source differs between the viewfinder and the zoom drive source of the taking lens and the zoom drive source of the optical zoom finder, the electronic zoom finder and the optical zoom finder can operate effectively even if they are simply shared. Can not.
[0009]
The present invention has been made to solve the above-described problems. In a digital camera including an imaging lens of a zoom focus method and an electronic zoom finder and an optical zoom finder, the electronic zoom finder and the optical zoom finder are provided. An object of the present invention is to make a digital camera compact and lightweight by sharing the zoom drive source of the photographing lens and the zoom drive source of the optical zoom finder without impairing each zoom function.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, a plurality of focal lengths that change stepwise are set in advance, and the focal lengths are changed by changing relative positions of a plurality of lens groups. An imaging lens that can be changed in a stepwise manner to the focal length of the imaging lens, and an imaging device that is provided at a predetermined position on the optical axis of the imaging lens and photoelectrically converts an image formed on the optical axis, An imaging unit that outputs image data, a zoom switch for changing a focal length of the imaging lens between the longest focal length and the shortest focal length, and the photographing lens according to a signal from the zoom switch A digital camera having a lens driving mechanism that changes relative positions of the plurality of lens groups, and a virtual zoom characteristic that connects the longest focal length and the shortest focal length of the imaging lens A first image magnification calculation unit that calculates a virtual focal length and an image magnification from a line and a time during which the zoom switch is continuously operated, and a light reception of the imaging unit from the current focal length of the imaging lens. A second image magnification calculator that calculates the magnification of the image formed on the surface, a virtual image magnification obtained by the first image magnification calculator, and an actual image magnification obtained by the second image magnification calculator. An electronic zoom finder comprising: an enlarged image data creating unit that creates enlarged image data obtained by enlarging the image data output from the imaging unit; and a display unit that displays an image using the enlarged image data; An optical zoom finder capable of capturing a subject light image independently of the lens and changing the magnification by moving the magnification changing lens to emit the subject light image to the eyepiece window; The driving force generated by the lens driving mechanism is transmitted to the lens for changing the magnification of the optical zoom finder, and the subject light is moved by moving the lens for changing the magnification in conjunction with the change of the focal position of the photographing lens. A finder driving mechanism for changing the magnification of an image, finder setting means for setting one of the electronic zoom finder and the optical zoom finder, and when the electronic zoom finder is set, the focal length of the photographing lens is The lens drive mechanism is driven stepwise in accordance with a signal from the zoom switch so that the magnification of the subject light image emitted to the eyepiece window is selected when the optical zoom finder is selected. The lens drive mechanism is continuously driven in response to a signal from the zoom switch so that changes continuously. Drive control means.
[0011]
According to the above configuration, the drive source of the zoom focus type photographing lens and the drive source of the lens constituting the optical zoom finder are shared by the lens drive mechanism, so that the size of the drive mechanism of the optical system can be reduced. .
[0012]
As in the example proposed in Japanese Patent Application No. 13-374417, when the electronic zoom finder is selected, the lens drive mechanism is driven step by step according to the operation of the zoom switch to gradually increase the focal length of the taking lens. On the other hand, by enlarging the captured image using the image magnification (actual image magnification) of the image captured by the imaging unit and the virtual image magnification corresponding to the switch operation based on the continuous operation time of the zoom switch A zoom image corresponding to the operation of the zoom switch is created, and the zoom image is displayed on the display unit. Therefore, the photographer can set the angle of view of the subject while viewing this display image.
[0013]
When the optical zoom finder is set, the lens drive mechanism is continuously driven according to the operation of the zoom switch, and the magnification changing lens is continuously changed, whereby the subject light emitted to the eyepiece window The image changes continuously. Therefore, the photographer can set the field angle of the subject while viewing the subject light image.
[0014]
In both the electronic zoom finder and the optical zoom finder, the change in the field angle of the subject that changes continuously according to the operation of the zoom switch can be visually recognized, so that the zoom finder function is not deteriorated.
[0015]
According to a second aspect of the present invention, in the digital camera according to the first aspect, an image magnification detecting unit that detects an image magnification of the optical zoom finder, and the finder is set from the electronic zoom finder to the optical zoom by the finder setting unit when setting an angle of view. An angle-of-view control means for driving the lens driving mechanism so that the image magnification detected by the image magnification detection means matches the virtual image magnification in the electronic zoom finder when the viewfinder is switched when the zoom finder is switched; It is provided.
[0016]
According to this configuration, when the viewfinder is switched from the electronic zoom finder to the optical zoom finder by the finder setting means when setting the angle of view, the image magnification detected by the image magnification detection means is a virtual image in the electronic zoom finder at the time of finder switching. The lens driving mechanism is driven so as to match the magnification, and the image magnification of the optical zoom finder is changed. As a result, even when the viewfinder is switched from the electronic zoom viewfinder to the optical zoom viewfinder while setting the angle of view, the image magnification of the subject optical image emitted from the eyepiece window of the optical zoom viewfinder is the same as the electronic zoom when the viewfinder is switched. Since it is the same as the image magnification of the zoom image by the finder, the operability for setting the angle of view is not lowered.
[0017]
According to a third aspect of the present invention, in the digital camera according to the second aspect, when the viewfinder is switched from the optical zoom finder to the electronic zoom finder by the finder setting means when setting an angle of view, the image magnification detection means A focal length for calculating a step-like focal length that can be set for the imaging lens that is closest to the focal length of the imaging lens corresponding to the image magnification of the optical zoom finder at the time of finder switching detected. A focal length changing means for changing a relative position of a plurality of lens groups of the imaging lens to change a focal length to a focal length calculated by the focal length calculating means; and the focal length calculating means. Using the calculated focal length of the imaging lens and the image magnification at the time of finder switching detected by the image magnification detection means An enlargement ratio calculating means for calculating an enlargement ratio of an image, and when the viewfinder is switched from the optical zoom finder to the electronic zoom finder by the finder setting means when setting an angle of view, the enlarged image data creating unit The image data output from the imaging unit after changing the focal length of the imaging lens by the focal length changing means is enlarged by the enlargement ratio calculated by the enlargement ratio calculating means to create enlarged image data, and the display The unit displays images using the enlarged image data.
[0018]
According to this configuration, when the viewfinder is switched from the optical zoom finder to the electronic zoom finder by the finder setting means at the time of setting the angle of view, imaging corresponding to the image magnification of the optical zoom finder at the time of finder switching detected by the image magnification detection means. A step-like focal length that can be set for the imaging lens that is closest to the focal length of the lens and that is equal to or shorter than the focal length is calculated. Further, the focal length of the imaging lens is changed to the focal length calculated by the focal length calculation means by changing the relative positions of the plurality of lens groups of the imaging lens, and detected by the focal length and image magnification detection means. The enlargement factor of the image is calculated by the enlargement factor calculator using the image magnification at the time of finder switching.
[0019]
Then, the enlarged image data is created by enlarging the image data of the subject image captured by the imaging unit after changing the focal length of the imaging lens at the enlargement ratio calculated by the enlargement ratio calculating means. Is used to display an image of the subject on the display unit.
[0020]
That is, when the electronic zoom finder is switched, a subject image having the same image magnification as that of the optical zoom finder at the time of finder switching is created and displayed on the display unit. As a result, even when the optical zoom finder is switched to the electronic zoom finder while setting the angle of view, a subject image having the same image magnification as that of the optical zoom finder at the time of finder switching is displayed on the display unit of the electronic zoom finder. Since it is displayed, the operability in setting the angle of view is not lowered.
[0021]
In a fourth aspect of the invention, a plurality of focal lengths that change stepwise are set in advance, and the focal length is changed stepwise to the plurality of focal lengths by changing the relative positions of the plurality of lens groups. An imaging lens that includes an imaging lens that can be changed, and an imaging device that is provided at a predetermined position on the optical axis of the imaging lens and photoelectrically converts an image formed on the optical axis, and outputs image data A zoom switch for changing the focal length of the imaging lens between its longest focal length and the shortest focal length, and relative to a plurality of lens groups of the photographing lens according to a signal from the zoom switch A digital camera having a lens driving mechanism for changing a general position, wherein a virtual zoom characteristic curve connecting the longest focal length and the shortest focal length of the imaging lens and the zoom switch A first image magnification calculation unit that calculates a virtual focal length and an image magnification from the time during which the camera is continuously operated, and an image is actually formed on the light receiving surface of the imaging unit from the current focal length of the imaging lens A second image magnification calculating unit that calculates the magnification of the image being imaged, a virtual image magnification obtained by the first image magnification calculating unit, and an actual image magnification obtained by the second image magnification calculating unit. An electronic zoom finder comprising an enlarged image data creation unit that creates enlarged image data obtained by enlarging output image data, a display unit that displays an image using the enlarged image data, and the photographing lens Generated by the lens drive mechanism and an optical zoom finder capable of capturing the subject light image and changing the magnification by moving the magnification change lens and emitting the subject light image to the eyepiece window The driving force is transmitted to the magnification changing lens of the optical zoom finder, and the magnification changing lens is moved in conjunction with the change in the focal position of the photographing lens, thereby changing the magnification of the subject optical image. When the finder drive mechanism, finder setting means for setting one of the electronic zoom finder and the optical zoom finder, and the electronic zoom finder are set, The lens driving mechanism is driven stepwise according to the signal from the zoom switch so that the focal length of the photographing lens changes stepwise, When the optical zoom finder is selected, the magnification of the optical zoom finder is continuously changed according to the signal from the zoom switch, and the step-like focus is maintained even when the signal from the zoom switch is cut off. Drive control means for driving the lens drive mechanism so as to prohibit the stop at a magnification other than the distance.
[0022]
According to the above configuration, the drive source of the zoom focus type photographing lens and the drive source of the lens constituting the optical zoom finder are shared by the lens drive mechanism, so that the size of the drive mechanism of the optical system can be reduced. .
[0023]
When the electronic zoom finder is set, the lens drive mechanism is driven stepwise according to the operation of the zoom switch to change the focal length of the taking lens stepwise, while the image captured by the imaging unit A zoom image corresponding to the operation of the zoom switch is created by enlarging the captured image using the magnification (actual image magnification) and the virtual image magnification corresponding to the switch operation based on the continuous operation time of the zoom switch. The zoom image is displayed on the display unit. Therefore, the photographer can set the angle of view almost continuously while viewing this display image.
[0024]
When the optical zoom finder is set, the lens driving mechanism is continuously driven according to the signal from the zoom switch, and thereby the subject light image emitted to the eyepiece window is continuously changed. When the photographer sets the angle of view (image magnification), the lens for driving the photographing lens and the optical zoom finder to the next step-shaped zoom position immediately after the photographing lens position when the photographer's zoom operation is completed. After the drive mechanism is driven and the photographic lens and optical zoom finder are driven to the step-like zoom position, the energization to the lens drive mechanism is stopped, so the angle of view (image magnification) intended by the photographer is almost set. It becomes possible to do. Setting the angle of view other than the step-like focal length is prohibited.
[0025]
In this way, since the change in the field angle of the subject that continuously changes according to the operation of the zoom switch can be visually recognized in both the electronic zoom finder and the optical zoom finder, the zoom finder function is not deteriorated.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a digital camera according to the present invention will be described. The digital camera according to the present embodiment includes an electronic zoom finder and an optical zoom finder, and the user can select and use one of the finder. The electronic zoom finder performs a finder function by capturing a moving image of a subject during shooting standby and displaying the captured image on a display unit including an LCD. In the present embodiment, a zoom focus type lens (also referred to as step zoom) that performs focal length adjustment (zooming) and focus adjustment (focusing) with a single motor is used as the imaging lens. In order to reduce the size and size of the digital camera, an electric motor that is a drive source of the imaging lens is also used as a drive source of the lens for changing the magnification of the optical zoom finder.
[0027]
In a zoom focus type imaging lens, the focal length of the imaging lens can only be set to one of a long focal end, a short focal end and at least one preset intermediate focal length. When the user selects a focal length other than these by operating the zoom switch, the image data of the captured image is enlarged to a predetermined image magnification by using a so-called electronic zoom method in combination with the display unit. indicate.
[0028]
On the other hand, when the optical zoom finder is selected, the electric motor is driven so as to continuously move the photographing lens in accordance with the user's operation of the zoom switch, thereby the lens for changing the magnification of the optical zoom finder. It is continuously moved to change the image magnification of the subject light image to a predetermined image magnification corresponding to the operation of the zoom switch.
[0029]
FIG. 1 shows the positional relationship of each component lens group when the configuration of the imaging lens and the focal length are changed. In FIG. 1, (a) is the retracted end where each lens group is moved to the retracted position so that the lens length becomes the shortest when the main switch is turned off, and (b) is the focal length of the imaging lens 10. (C) shows the case where the focal length of the imaging lens 10 is set to the long focal end.
[0030]
As is well known, the focal length of a zoom lens can be changed by changing the relative positions of a plurality of lens groups constituting the optical system. In addition, in a lens called an inner focus type, the in-focus position can be changed by changing the position of some of the plurality of lens groups constituting the optical system.
[0031]
In the configuration example shown in FIG. 1, the focal length of the imaging lens 10 is changed by changing the positions of the first lens group 11, the second lens group 12, and the third lens group 13 from the subject (object) side. Further, the focusing position is adjusted by changing the position of the third lens group 13 in the optical axis direction without moving the positions of the first lens group 11 and the second lens group 12 in the optical axis direction. Note that the fourth lens group 14 closest to the image sensor 21 is fixed.
[0032]
The shape of the cam groove for changing the position of the third lens group 13 is shown in FIG. In the drawing, the retractable end P0 is a lens group, in particular, the third lens group in this case, so that the optical performance of the imaging lens 10 is ignored when the main switch of the digital camera is turned off, and the lens length is minimized. The position of the lens guide pin corresponding to the storage position 13 (hereinafter simply referred to as “position of the third lens group 13”) is shown.
[0033]
A point P1 indicates the position of the third lens group 13 in a state where the imaging lens 10 is focused on an object at the short focal point where the focal length is the shortest and at infinity. A point P2 indicates the position of the third lens group 13 in a state where the imaging lens 10 is focused on a subject at a short focal point and at a close distance that is acceptable in terms of optical performance. In the focus section between the point P1 and the point P2, the first lens group 11 and the second lens group 12 do not basically move by a known (not shown) cam mechanism, and the third lens group 13 moves linearly, Adjust the focus position. The same applies to the following points P3 and P4, P5 and P6, P7 and P8, and P9 and P10.
[0034]
Points P3, P5, and P7 indicate the positions of the third lens group 13 in a state where the focal length of the imaging lens 10 is an intermediate focal length between the short focal end and the long focal end and is focused on a subject at infinity. . Points P4, P6, and P8 respectively indicate the positions of the third lens group 13 in a state where the focal length of the imaging lens 10 is in the middle between the short focal end and the long focal end and is focused on a subject at a close distance. . A point P9 indicates the position of the third lens group 13 in a state where the imaging lens 10 has a long focal point with the longest focal length and is focused on a subject at infinity. A point P10 indicates the position of the third lens group 13 in a state where the imaging lens 10 is at the long focal end and is focused on a subject at a close distance.
[0035]
In FIG. 2, the solid lines connecting the points P1, P2, P3, P4, P5, P6, P7, P8, P9 and P10 are actual cam curves. On the other hand, an alternate long and short dash line connecting the points P1, P3, P5, P7, and P9 indicates a virtual cam curve (virtual zoom characteristic) connecting the long focal end and the short focal end of the imaging lens 10.
[0036]
Next, FIG. 3 shows a block configuration of the digital camera according to the present embodiment. As described above, the electronic zoom finder performs a finder function by displaying an image by capturing a moving image of the subject by the imaging unit 20 during shooting standby and displaying the captured image on the display device 51. Therefore, the photographing lens 10 also serves as an optical system of an electronic zoom finder.
[0037]
The photographic lens 10 and the optical zoom finder 70 are zoom-driven by transmitting a driving force of an electric motor 71 such as a stepping motor via a transmission member 72. The optical zoom finder 70 includes an objective lens composed of two components of a convex lens and a concave lens whose lens interval is variable. The optical zoom finder 70 changes the image magnification of the subject light image emitted to the eyepiece window by moving one of the objective lenses on the optical axis by the driving force of the electric motor 71. The transmission member 72 is formed by connecting a plurality of gears, and transmits the driving force of the electric motor 71 to the photographing lens zoom driving mechanism 10A of the photographing lens 10 and the optical finder zoom driving mechanism 70A of the optical zoom finder 70. The optical finder zoom drive mechanism 70A includes cam means (not shown), and when the electric motor 71 is rotated by the cam means, the virtual cam curve in which the third lens group 13 of the photographing lens 10 is drawn in the cam groove. The lens group of the optical zoom finder 70 is moved so as to be substantially equal to the change in the focal length (change in the angle of view) of the photographic lens 10 when moved up.
[0038]
Drive control of the electric motor 71 is performed by the overall control unit 40 via the lens control unit 30. FIG. 4 is a diagram showing the relationship between the operation amount of the zoom switches ST and SW and the movement amount of the photographing lens when the electronic zoom finder is selected. FIG. 5 is a diagram showing the relationship between the amount of operation of the zoom switches ST and SW and the amount of movement of the photographing lens when the optical zoom finder is selected.
[0039]
As shown in FIG. 4, when the electronic zoom finder is selected, the electric motor 71 is intermittently driven so that the photographing lens 10 moves stepwise with respect to the operation amount of the zoom switches SW and ST. Is done. Hereinafter, this drive mode is referred to as “step zoom drive mode”. This is because the focal length of the photographic lens 10 is switched in a stepped manner. On the other hand, when the optical zoom finder is selected, as shown in FIG. 5, the electric motor 71 is continuously driven so that the photographing lens 10 continuously moves with respect to the operation amount of the zoom switches SW and ST. Is done. Hereinafter, this drive mode is referred to as “continuous zoom drive mode”. This is because the lens for changing the magnification of the optical zoom lens is continuously moved to continuously change the image magnification of the subject optical image.
[0040]
On the optical axis L of the imaging lens 10, for example, an imaging element 21 such as a CCD or a MOS is provided. As is well known, on the light receiving surface of the image sensor 21, a predetermined number of pixels each including a small photoelectric conversion element are arranged in the vertical direction and the horizontal direction, and pixel signals (analog data such as charge amount) from each pixel. ) Is output. The pixel signal from the image sensor 21 is converted into a digital signal by the A / D converter 22 and then subjected to white balance adjustment and γ correction by the image processing unit 23 and is temporarily stored in the image data memory 24. The The image pickup unit 20 includes the image pickup device 21, the A / D converter 22, the image processing unit 23, the image data memory 24, and the like.
[0041]
In the following description, each pixel signal is digitized and subjected to predetermined image processing is referred to as “pixel data”, and “pixel data” is an image configured by arranging “pixel data” in a predetermined order. ".
[0042]
The lens control unit 30 controls the zoom operation of the imaging lens 10 and the optical zoom finder 70 by controlling the driving of the electric motor 71. Each of the photographing lens zoom drive mechanism 10A and the optical finder zoom drive mechanism 70A includes a cam cylinder, a gear train, an encoder for detecting the rotation position and rotation direction of the cam cylinder, and the like. The encoder detection information is input to the overall control unit 40. In the upper part of FIG. 2, each of the photographic lens zoom drive mechanism 10A and the optical finder zoom drive mechanism 70A corresponding to the cam groove position of the third lens group 13 of the photographic lens 10, that is, corresponding to the rotation angle of the cam cylinder having the cam groove. The encoder output is shown.
[0043]
The lens control unit 30 controls the number of rotations and the rotation direction of the electric motor 71 by a control signal from the overall control unit 40, and the relative positions of a plurality of lens groups constituting the imaging lens 10 and the objective of the optical zoom finder 70. The interval between the concave and convex lenses constituting the lens is changed. The overall control unit 40 uses the positional information (encoder detection signal) input from each of the photographing lens zoom driving mechanism 10A and the optical finder zoom driving mechanism 70A, and the current focal length and image magnification of the imaging lens 10, the optical zoom finder. An image magnification of 70 is detected.
[0044]
The overall control unit 40 executes a variety of programs including a ROM storing a predetermined program for controlling the entire digital camera, a RAM for temporarily storing data to be processed such as image data, and the predetermined program. In order to realize the function, it is composed of a CPU or the like. The overall control unit 40 includes shutter switches S1 and S2, zoom switches SW and ST, image determination switch Sa, image erasure switch Sb, finder setting switch Sc, recording unit 60, photometry unit 61, distance measurement unit 62, and the like. Is connected. Details of the overall control unit 40 will be described later.
[0045]
The display unit (electronic zoom finder) 50 includes a display device 51 such as an LCD and a display image data memory 52 such as a RAM for temporarily storing display image data to be displayed on the display device 51. It is configured.
[0046]
The shutter switch S1 is a switch that is turned on when a user puts a finger on a shutter operation button provided on an upper portion of the camera housing or the like, and is a switch for performing a shooting preparation operation. The shutter switch S2 is a switch that is turned on when the shutter operation button is pushed down to the end, drives the imaging unit 20 to capture image data, and records the captured image data on a recording medium such as a memory card by the recording unit 60. It is a switch to do.
[0047]
When the electronic zoom finder 50 is selected, the zoom switch SW uses the electronic zoom method in a direction in which the image magnification of the subject displayed on the display device 51 decreases, that is, the focal length of the imaging lens 10 is shortened stepwise. When the optical zoom finder 70 is selected, the switch in which the image magnification of the subject viewed from the eyepiece window is reduced, that is, the focal length of the photographing lens 10 is continuously set. This switch is operated to shorten the focal length of the lens of the optical zoom finder 70 that is interlocked with the lens while continuously shortening the lens. On the other hand, when the electronic zoom finder 50 is selected, the zoom switch ST is an electronic zoom method in which the image magnification of the subject displayed on the display device 51 is increased, that is, the focal length of the imaging lens 10 is increased stepwise. Are used to operate in the direction in which the image magnification increases, and when the optical zoom finder 70 is selected, the direction in which the image magnification of the object seen from the eyepiece window increases, that is, the focal length of the photographing lens 10 is continuously set. It is a switch that operates in a direction that continuously increases the focal length of the lens of the optical zoom finder 70 that is linked to the optical zoom finder 70 while it is long. The zoom switches SW and ST are provided on the upper part of the camera housing as in the case of the shutter operation buttons, and are configured to be alternatively turned on (so that they cannot be turned on simultaneously).
[0048]
The image determination switch Sa is a switch for determining whether or not to record an image (image data) displayed on the monitor on the display device 51 on a recording medium. The image erasure switch Sb is a switch used when the image data is not recorded on the recording medium. When the image erasure switch Sb is turned on, the overall control unit 40 stores the image data temporarily stored in the image data memory 24. to erase.
[0049]
In a general digital camera, an image read from the imaging unit 20 after the shutter switch S2 is turned on is automatically recorded once on a recording medium. When erasing the image, the image data recorded on the recording medium is used. Delete by post-processing. In this embodiment, by providing the image determination switch Sa and the image erasing switch Sb, unnecessary image data can be erased before the image data is recorded on the recording medium.
[0050]
Since the digital camera according to the present embodiment uses the zoom focus type imaging lens 10, the image captured by the imaging unit 20 is a subject image that is zoomed in stages. Therefore, when the display device 51 is caused to function as an electronic zoom finder, in this embodiment, the image magnification set by the zoom switches ST and SW is the same as the image magnification optically set by the focal length of the photographing lens 10. When the image picked up by the image pickup unit 20 is displayed on the display device 51 as it is, when it is not the same, a part of the center of the picked-up image is enlarged by image processing and displayed on the display device 51. A subject image having an angle of view corresponding to the operation of the zoom switches ST and SW is made visible.
[0051]
When recording a captured image, if the angle of view set by the zoom switches ST and SW is the same as the angle of view optically zoomed by the photographic lens 10, the image captured by the imaging unit 20 is recorded on the recording medium. If the images are recorded but are not the same, an image (hereinafter referred to as an electronic zoom image) created by enlarging a part of the center of the captured image by image processing to display the angle of view on the display device 51 is referred to as a recording medium. To be recorded.
[0052]
The finder setting switch Sc is a switch that switches between an electronic zoom finder and an optical zoom finder. A finder setting signal from the finder setting switch Sc is input to the overall control unit 40. When the setting signal for the optical zoom switch is input to the overall control unit 40, the overall control unit 40 drives the electric motor 71 in the continuous zoom drive mode via the lens control unit 30, and the setting signal for the electronic zoom switch is input. Then, the overall control unit 40 drives the electric motor 71 in the step zoom drive mode via the lens control unit 30.
[0053]
The recording unit 60 records image data on a recording medium such as a memory card. The photometry unit 61 detects the intensity of light transmitted through the imaging lens 10 and calculates subject luminance. In the case of a digital camera, the pixel itself of the image sensor 21 is a photoelectric conversion element. Therefore, by subjecting the pixel data output from the image sensor 21 or the image data after image processing output from the image capturing unit 20 to arithmetic processing, Luminance can be determined.
[0054]
The distance measuring unit 62 measures the distance to the subject and controls the lens control unit 30 to focus the imaging lens 10 on the subject. In general, in the case of a digital camera, since the image sensor 21 itself can function as a distance measuring sensor, a state in which the contrast of image data output from the image capturing unit 20 is maximized while the lens control unit 30 is appropriately driven. Focusing (so-called “mountain climbing method”).
[0055]
When the electronic zoom finder is set by the finder setting switch Sc, the overall control unit 40 functions as the first image magnification calculation unit 41, and a virtual zoom characteristic curve that connects the longest focal length and the shortest focal length of the imaging lens 10. And the time during which the zoom switch SW or ST is operated continuously, the virtual focal length and the image magnification are calculated. In the present embodiment, since the zoom lens system is used as the imaging lens 10, the imaging lens 10 can take only one of a plurality of preset focal lengths. On the other hand, it is displayed on the display device 51 of the display unit 50 for the user as if the focal length of the imaging lens 10 is continuously changed by using the electronic zoom method together. Change the image magnification of the image. Therefore, it is necessary to calculate the virtual image magnification γ (virtual focal length of the imaging lens 10) of the image displayed on the display device 51 of the display unit 50 from the operation time of the zoom switch SW or ST.
[0056]
The virtual image magnification γ is α, which is the actual image magnification of the imaging lens 10, and β is an enlargement ratio when an electronic zoom image is created by enlarging a part of the center of an image captured at the image magnification α. Then, γ = α × β is calculated. Here, the image magnification α is an image magnification corresponding to a plurality of focal lengths preset in the photographing lens 10. In the present embodiment, as shown in FIG. 6, the focal length of the taking lens 10 can be switched to five steps fT, f1, f2, f3, and fW, so that the image magnification α corresponding to these focal lengths fT to fW. Is αT, α1, α2, α3, αW, and αT / α1 = α1 / α2 = α2 / α3 = α3 / αW = 1.5, β is 1 ≦ β ≦ 1.5, and the virtual image magnification γ is ,
(A) αW ≦ γ <α3 γ = αW × β
(B) α3 ≦ γ <α2 γ = α3 × β
(C) α2 ≦ γ <α1 γ = α2 × β
(D) α1 ≦ γ <αT γ = α1 × β
(E) γ = αT γ = αT
It becomes. Of course, here, assuming an electronic zoom at a focal length fT, a virtual focal length γ = α4 of α4 = βmax × αT = 1.5 × αT is set,
(E ′) αT ≦ γ ≦ α4 γ = αT × β
In this embodiment, it is assumed that electronic zoom is not performed at the focal length fT.
[0057]
Next, the overall control unit 40 functions as the second image magnification calculation unit 42, and uses the output from the encoder of the photographing lens zoom drive mechanism 10A, that is, αT or α1 or α2 or α3 or αW, of the imaging lens 10 at the present time. The focal length is calculated, and the magnification α of the image actually formed on the light receiving surface of the image sensor 21 is calculated. That is, it is necessary to know the actual image magnification α of the image formed on the image sensor 21 in order to calculate the enlargement ratio β of the image data by the electronic zoom method.
[0058]
Further, the overall control unit 40 functions as an enlarged image data creation unit 43, and an electronic zoom method using the virtual image magnification γ by the first image magnification calculation unit 41 and the actual image magnification α by the second image magnification calculation unit 42. The enlargement ratio β is calculated, and enlarged image data (electronic zoom image data) obtained by enlarging the image data output from the imaging unit 20 is created.
[0059]
The enlarged image data creation unit 43 further includes an electronic zoom unit 44 for extracting pixel data used for enlargement processing from the image data output from the imaging unit 20 using the calculated enlargement factor β, and a display unit In order to display a monitor image on 50 display devices 51, a pixel data thinning unit 45 that thins out the extracted pixel data to create display image data, and a process for enlarging the extracted pixel data A pixel data interpolating unit 46 that interpolates pixel data for the deficient pixels, a recording image data creating unit 47 that creates the recording image data by synthesizing the interpolated pixel data with the extracted pixel data, and the like Consists of. The image data created by the recording image data creation unit 47 is input to the recording unit 60 and recorded on a recording medium such as a memory card.
[0060]
Next, pixel data extraction, pixel data thinning, and pixel data interpolation will be described. As described above, the imaging lens 10 can take only one of a plurality of preset focal lengths, and when the user selects an intermediate focal length between them, the electronic zoom method is used to select the intermediate focal length. A focal length (or image magnification) is realized.
[0061]
FIG. 6 shows the relationship between the focal length that the imaging lens 10 can take when the electronic zoom finder is set, the image at each focal length, and the image at the intermediate focal length by the electronic zoom.
[0062]
In FIG. 6, (a1) to (a5) in the upper stage show the appearance of the camera (lens portion) at each of the focal lengths fT, f1, f2, f3, and fW that the imaging lens 10 can take. Here, it is assumed that the focal length of the imaging lens 10 and the protrusion amount of the lens from the camera body are substantially proportional.
[0063]
Middle (b1) to (b5) show images at the respective focal lengths fT, f1, f2, f3, and fW, and their image magnifications αT, α1, α2, α3, and αW in order. Each image represents an image actually formed on the image sensor 21 by the imaging lens 10.
[0064]
The lower (c1) to (c4) show images at the (virtual) focal lengths fm1, fm2, fm3 and fm4 between the focal lengths fT and f1 and their image magnifications γ1, γ2, γ3 and γ4 as an example of electronic zoom. Show. In these cases, the focal length and image magnification of the imaging lens 10 are not actually changed, and the image indicated by the outermost frame in (b2) is formed on the imaging device 21.
[0065]
If the virtual focal length calculated by the first image magnification calculation unit 41 is fm1 (image magnification γ1), the electronic zoom unit 44 extracts only pixel data included in the frame B in the figure. In other words, the pixel data outside the frame B is discarded. Similarly, if the virtual focal length is fm4 (image magnification γ4), the electronic zoom unit 44 extracts only pixel data included in the frame A. This process is called “extraction of pixel data”.
[0066]
If the horizontal dimension of the image sensor 21 is L, the horizontal dimension of the frame A is LA, and the horizontal dimension of the frame B is LB, γ1 = α1 × β1 = α1 × (L / LB), γ4 = α1 × β4 = α1 × (L / LA).
[0067]
By the way, although the number of pixels of the image sensor 21 depends on the purpose, it reaches several million pixels for digital cameras. On the other hand, in the case of a small LCD (liquid crystal display element) used for a viewfinder of a digital camera, the number of pixels is at most tens of thousands of pixels. Therefore, the pixel data thinning unit 45 uses the pixel data extracted by the electronic zoom unit 44 to extract one pixel data from several pixels to several tens of pixels adjacent in the vertical and horizontal directions of the frame. Alternatively, the average value of these pixel data is obtained, and the number of pixel data is reduced to form display image data. This is called “pixel data thinning”. Since the number of extracted pixel data decreases as the enlargement rate β increases, the pixel data thinning rate is inversely proportional to the enlargement rate.
[0068]
On the other hand, the pixel data extracted by the electronic zoom unit 44 is smaller than the number of pixels of the image sensor 21 except when the enlargement ratio β = 1, that is, when the electronic zoom is not performed. Assuming that the pixel data is recorded as is on the recording medium as image data, and is output to a printer or the like using the image data, the image becomes coarse and the image quality deteriorates as the enlargement ratio β increases. Therefore, in order to make the number of pixels the same as the image data when the electronic zoom is not performed, the pixel data interpolation unit 46 first replaces the addresses of the extracted pixel data according to the enlargement ratio β. Do. Then, since a gap is formed between the pixels, new pixel data is created using a plurality of pixel data adjacent to the gap in order to fill the gap. This is called “interpolation of pixel data”.
[0069]
Next, FIG. 7 shows zoom characteristics of the imaging lens 10 when the electronic zoom finder is set. In the figure, a step-like solid line indicates the actual zoom characteristic of the imaging lens 10, and an alternate long and short dash line indicates a virtual zoom characteristic. Further, the left half of the figure shows a case where the zoom switch ST is turned on and the focal length of the imaging lens 10 is changed from the short focus side to the long focus side, and the right half is the zoom switch SW turned on and the focus of the imaging lens 10 is shown. A case where the distance is changed from the long focal side to the short focal side will be described.
[0070]
As can be seen from the figure, when the focal length of the imaging lens 10 is changed from the short focal length side to the long focal length side, the focal length of the imaging lens 10 changes later than the virtual focal length. On the other hand, when the focal length of the imaging lens 10 is changed from the long focal side to the short focal side, the focal length of the imaging lens 10 changes before the virtual focal length. By changing the focal length of the imaging lens 10 in this way, an image having a wider range than the image necessary for the electronic zoom is always formed on the imaging element 21.
[0071]
As exemplified in the present embodiment, when the focal length of the imaging lens 10 is changed in five stages and the maximum value βmax = 1.5 of the enlargement ratio by electronic zoom is 1.5 × (5-1) power≈5 And a zoom ratio of 5 times is obtained.
[0072]
On the other hand, when the optical zoom finder is set by the finder setting switch Sc, a lens for changing the magnification of the optical zoom finder 70 is provided in the optical finder zoom drive mechanism 70A according to the operation of the zoom switch SW or ST. The third lens group 13 of the photographing lens 10 is moved substantially on the virtual cam curve shown in FIG. The image zoom characteristic of the optical zoom finder 70 is substantially the same as the virtual zoom characteristic of FIG.
[0073]
Next, the imaging sequence of the digital camera in the present embodiment will be described with reference to the flowcharts shown in FIGS.
[0074]
First, when the power switch is turned on (step # 1), the overall control unit 40 drives the lens control unit 30, pulls out the imaging lens 10 from the retracted position, and sets the focal length of the imaging lens 10 to the short focal end (WIDE). End) (step # 3).
[0075]
When the focal length of the imaging lens 10 is set to the short focal end, the setting content of the finder is discriminated by an input signal from the finder setting switch Sc (step # 5). If the electronic zoom finder is set, step # Then, the “viewing angle setting process using the electronic zoom finder” is executed according to the flowcharts of FIGS. 9 and 10.
[0076]
When the process proceeds to the angle-of-view setting process using the electronic zoom finder, the overall control unit 40 first displays the prohibition of use of the optical zoom finder 70 on the display device 51 (step # 7-1). In step # 7-1, the optical zoom finder 70 may be set in an unusable state. Subsequently, it is determined whether or not the optical zoom finder is switched to the electronic zoom finder based on an input signal from the finder setting switch Sc (step # 7-2). The electronic zoom unit 44 initially sets the enlargement ratio β to “1.0” (step # 7-3). For example, the distance measuring unit 62 drives the lens control unit 30 while monitoring image data output from the imaging unit 20, and performs a focusing operation so that the contrast is maximized (step # 7-4).
[0077]
When the focusing operation of the imaging lens 10 is completed, the pixel data thinning unit 45 reads the image data output from the imaging unit 20, performs a thinning process, and creates display image data (electronic zoom image) (step). # 7-5). The display image data is temporarily input to the display image data memory 52, and then displayed on the monitor 51 (step # 7-6). Note that the monitor image data is updated every time a predetermined time elapses, and a timer for updating the image data is started.
[0078]
If the electronic zoom finder is set by finder switching in step # 7-2 (YES in step # 7-2), the processes in steps # 7-3 to # 7-6 are skipped.
[0079]
Subsequently, the overall control unit 40 determines whether or not the zoom switch ST or SW is turned on (steps # 7-7 and # 7-8). If the zoom switches ST and SW are not turned on (NO in steps # 7-7 and # 7-8), the process returns to step # 11.
[0080]
On the other hand, when the zoom switch ST is turned on (YES in step # 7-7), the first image magnification calculator 41 calculates the virtual image magnification γ from the virtual zoom characteristics and the operation time of the zoom switch ST (step #). 7-9). In parallel with this, the second image magnification calculator 42 calculates the actual image magnification α by the imaging lens 10 from the output of the encoder of the photographing lens zoom drive mechanism 10A (step # 7-10). Further, the calculated virtual image magnification γ and the actual image magnification α are respectively input to the electronic zoom unit 44, and the enlargement ratio β is calculated (step # 7-11).
[0081]
When the enlargement factor β is calculated, the electronic zoom unit 44 extracts predetermined pixel data from the image data output from the imaging unit 20 using the calculated enlargement factor β, and performs electronic zoom processing ( Step # 7-12). The pixel data thinning unit 45 thins the extracted pixel data (step # 7-13), and the display unit 50 updates the monitor display on the display device 51 using the thinned display image data. (Step # 7-14).
[0082]
Further, the overall control unit 40 determines whether or not the zoom switch ST is turned off (step # 7-15). When the zoom switch ST is not turned off (NO in Step # 7-16), the overall control unit 40 determines whether or not the enlargement ratio β is “1.5” (Step # 7-16). When the enlargement ratio β is not “1.5” (NO in step # 17-16), the overall control unit 40 repeats the processing of steps # 7-9 to # 7-14 to calculate the virtual image magnification γ, The calculation of the actual image magnification α, the calculation of the enlargement factor β, the electronic zoom process, the thinning process, and the monitor display update are sequentially performed. On the other hand, when the magnification factor β is “1.5” (YES in step # 7-16), the overall control unit 40 drives the lens control unit 30 to increase the focal length of the imaging lens 10 by one step. It is changed to the long focal side (step zoom drive: step # 7-17). At this time, the movement destination position of the photographic lens 10 is within the focus section on the one-stage long focal side in FIG. 2, but a position where the subject distance is substantially the same as the position focused before the movement is desirable. Thereafter, the process proceeds to step # 7-9, and the calculation of the virtual image magnification γ, the calculation of the actual image magnification α, the calculation of the enlargement factor β, the electronic zoom process, the thinning process, and the update of the monitor display are repeated.
[0083]
When the zoom switch ST is turned off (YES in step # 7-15), the overall control unit 40 further determines whether or not the zoom switch SW is turned on (step # 7-8). When the zoom switch SW is turned on (YES in step # 7-8), the overall control unit 40 calculates the virtual image magnification γ (FIG. 10, step # 7-18), and sets the actual image magnification α by the imaging lens 10. Calculation (step # 7-19), calculation of enlargement ratio β (step # 7-20), electronic zoom processing (step # 7-21), pixel data thinning-out processing (step # 7-22), monitor display update (Step # 7-23) is performed in order.
[0084]
Further, the overall control unit 40 determines whether or not the zoom switch SW is turned off (step # 7-24). When the zoom switch SW is not turned off (NO in step # 7-24), the overall control unit 40 determines whether or not the enlargement ratio β is “1.0” (step # 7-25). When the enlargement ratio β is not “1.0” (NO in step # 17-25), the overall control unit 40 repeats the processes of steps # 7-18 to # 7-23 to calculate the virtual image magnification γ, The calculation of the actual image magnification α, the calculation of the enlargement factor β, the electronic zoom process, the thinning process, and the monitor display update are sequentially performed. On the other hand, when the magnification ratio β is 1.0 (YES in step # 7-25), the overall control unit 40 drives the lens control unit 30 to reduce the focal length of the imaging lens 10 by one step. (Step zoom drive: Step # 7-26). At this time, the movement destination position of the photographing lens 10 is desirably a position where the subject distance is substantially the same as the focus position before the movement, as in the case where the zoom switch ST is turned on. Thereafter, the process proceeds to step # 7-18, and the calculation of the virtual image magnification γ, the calculation of the actual image magnification α, the calculation of the enlargement ratio β, the electronic zoom process, the thinning process, and the update of the monitor display are repeated.
[0085]
Note that since the focal length of the imaging lens 10 is initially set to the short focal point when the camera is activated, the overall control unit 40 does not drive the lens control unit 30 even when the zoom switch SW is turned on. The processes of 7-18 to # 7-23 are repeated.
[0086]
Returning to step # 5 in FIG. 8, if the optical zoom finder 70 is set, the process proceeds to step # 9, and “viewing angle setting processing by the optical zoom finder” is executed according to the flowchart in FIG.
[0087]
In the angle of view setting process by the optical zoom finder, the overall control unit 40 first stops the power supply to the display unit 50 and turns off the display on the display device 51 (step # 9-1). Subsequently, the overall control unit 40 determines whether or not the zoom switch ST or SW is turned on (steps # 9-2 and # 9-3).
[0088]
When the zoom switch ST is turned on (YES in step # 9-2), the overall control unit 40 continuously drives the electric motor 71 to the tele side via the lens control unit 30 to keep the imaging lens 10 on the tele side. (Step # 9-4). By continuously driving the electric motor 71, the image magnification γf of the optical zoom finder 70 continuously increases. The overall control unit 40 is based on the output from the encoder of the optical finder zoom drive mechanism 70A of the optical zoom finder 70 while the zoom switch ST is kept on (loop of steps # 9-4 to # 9-6). Then, it is monitored whether or not the lens for changing the magnification of the optical zoom finder 70 has reached the tele end (step # 9-5), and when the lens for changing the magnification has reached the tele end (in step # 9-5). YES), the drive of the electric motor 71 is stopped, the image magnification γf of the optical zoom finder 70 is held at the maximum value (step # 9-7), and the process returns to step # 9-3. If the zoom switch ST is turned off before the magnification changing lens reaches the telephoto end (YES in step # 9-6), the overall control unit 40 stops driving the electric motor 71 and the optical zoom finder 70. Is held at the set magnification (step # 9-7), and the process returns to step # 9-3.
[0089]
In step # 9-3, the overall control unit 40 determines whether or not the zoom switch SW is turned on. When the zoom switch SW is turned on (YES in step # 9-3), the overall control unit 40 continuously drives the electric motor 71 to the wide side via the lens control unit 30 to widen the imaging lens 10. (Step # 9-8). By continuously driving the electric motor 71, the image magnification γf of the optical zoom finder 70 continuously decreases. The overall control unit 40 is based on the output from the encoder of the optical finder zoom drive mechanism 70A of the optical zoom finder 70 while the zoom switch SW is kept on (loop of steps # 9-8 to # 9-10). Then, it is monitored whether the lens for changing the magnification of the optical zoom finder 70 has reached the wide end (step # 9-9). When the lens for changing the magnification has reached the wide end (in step # 9-9). (YES), the drive of the electric motor 71 is stopped, the image magnification γf of the optical zoom finder 70 is held at the minimum value (step # 9-11), and the process returns to step # 9-2. If the zoom switch SW is turned off before the lens for changing the magnification reaches the wide end (YES in Step # 9-10), the overall control unit 40 stops driving the electric motor 71 and the optical zoom finder 70. Is held at the set magnification (step # 9-11), and the process returns to step # 9-2.
[0090]
When the zoom switches ST and SW are turned off (NO in steps # 9-2 and # 9-3), the overall control unit 40 returns to step # 11, assuming that the angle of view setting by the zoom switches ST and SW has been completed. To do.
[0091]
In step # 11 (FIG. 8), the overall control unit 40 determines whether or not the finder is switched based on an input signal from the finder setting switch Sc. When switching from the optical zoom finder to the electronic zoom finder is instructed, the process proceeds to step # 13, and "finder switching processing I" is executed according to the flowchart shown in FIG.
[0092]
When the process proceeds to the finder switching process I, the overall control unit 40 detects the current image magnification γf of the optical zoom finder 70 based on the output from the encoder of the optical finder zoom drive mechanism 70A (step # 13-1). Further, the overall control unit 40 calculates the current image magnification α of the imaging lens 10 from the output of the encoder of the photographing lens zoom drive mechanism 10A by the second image magnification calculation unit 42, and the image magnification α and the image of the optical zoom finder 70 are calculated. An enlargement ratio β (= γf / α) is calculated from the magnification γf (step # 13-2). Thereafter, based on the output from the encoder of the photographic lens zoom drive mechanism 10A by driving the electric motor 70, the photographic lens 10 is adjusted to the closest step zoom position on the wide side, that is, the focus adjustment range of the photographic lens 10 closest to the wide side. , Move to the focus section in FIG. Subsequently, focusing operation is performed in the section by the distance measuring unit 62 (step # 13-3).
[0093]
When the enlargement factor β is calculated, the overall control unit 40 uses the electronic zoom unit 44 to extract predetermined pixel data from the image captured by the imaging unit 20, and uses the enlargement factor β to perform electronic zoom processing. (Step # 13-4). Further, the pixel data extracted by the pixel data thinning unit 45 is thinned to generate display image data (step # 13-5), and the display unit 50 uses the display image data to display the subject on the display device 51. The image is displayed on the monitor (step # 13-6), and the process returns to step # 7 (FIG. 8, view angle setting process using the electronic zoom finder), and the image corresponding to the operation of the zoom switch ST or SW using the electronic zoom finder described above. Perform the corner setting process.
[0094]
In the processes of steps # 13-1 to # 13-6 described above, when the electronic zoom finder is switched, the virtual image magnification γ of the monitor image displayed on the display device 51 is set by the optical zoom finder immediately before the finder switching. The image magnification γf is adjusted. In this way, even when the viewfinder is switched, the currently set angle of view does not change, and the user can continuously set the angle of view without a sense of incongruity.
[0095]
On the other hand, if switching from the electronic zoom finder to the optical zoom finder is instructed in step # 11 (FIG. 8), the process proceeds to step # 15, and “finder switching processing II” is executed according to the flowchart shown in FIG. The
[0096]
When the finder switching process II is started, the overall control unit 40 calculates the actual image magnification α by the imaging lens 10 from the output of the encoder of the photographing lens zoom drive mechanism 10A by the second image magnification calculation unit 42 (step # 15- 1). Further, the first image magnification calculator 41 calculates the virtual image magnification γ from the operation time of the zoom switch ST or SW immediately before the finder switching in the electronic zoom finder and the virtual zoom characteristic (step # 15-2).
[0097]
Subsequently, the overall control unit 40 continuously drives the electric motor 71 to the tele side until the image magnification γf of the optical zoom finder 70 matches the virtual image magnification γ based on the encoder output of the optical finder zoom drive mechanism 70A. Then, after continuously moving the imaging lens 10 to the tele side (loop of steps # 15-3 and # 15-4 and step # 15-5), step 9 (FIG. 8, setting of the angle of view by the optical zoom finder) Returning to (Processing), an angle-of-view setting process corresponding to the operation of the zoom switch ST or SW by the optical zoom finder 70 described above is performed.
[0098]
Although not shown, if γ = α, the image magnification γf of the optical zoom finder 70 matches the virtual magnification γ, so that the image magnification adjustment of the optical zoom finder 70 is not performed.
[0099]
In the loop of steps # 15-3 and # 15-4 and the process of step # 15-5, the image magnification γf of the optical zoom finder 70 is set by the electronic zoom finder immediately before the finder switching when the optical zoom is switched. The virtual image magnification γ is adjusted. In this way, even when the viewfinder is switched, the currently set angle of view does not change, and the user can continuously set the angle of view without feeling uncomfortable.
[0100]
Returning to FIG. 8, if there is no finder switching in step # 11, the overall control unit 40 proceeds to step # 17 and determines whether or not the shutter switch S1 is turned on. If the shutter switch S1 has not been turned on (NO in step # 17), the process returns to step # 5 and the above-described flow of angle of view setting processing by the electronic zoom finder or optical zoom finder is performed again.
[0101]
When the switch S1 is turned on (YES in step # 17), “imaging preparation processing” is executed according to the flowchart shown in FIG. 14 (step # 19).
[0102]
When the process proceeds to the shooting preparation process, the overall control unit 40 determines whether the electronic zoom finder is set (step # 19-1). When the electronic zoom finder is set (YES in step # 19-1), the overall control unit 40 redoes the focusing operation with the focal length of the imaging lens 10 at that time by the distance measuring unit 62 (step # 19). -2). Further, the photometric unit 61 measures the subject luminance using the image data from the imaging unit 20 (photometric process: step # 19-3), and based on the measured subject luminance, the aperture value of the imaging lens 10 and the imaging element 21 are measured. Exposure conditions such as exposure time (charge accumulation time) are calculated (step # 19-4). Further, the overall control unit 40 calculates the enlargement ratio β from the virtual image magnification γ and the actual image magnification α by the electronic zoom unit 44 (step # 19-5), and returns to step # 21.
[0103]
On the other hand, when the optical zoom finder is set (NO in step # 19-1), the overall control unit 40 determines the current zoom position of the photographic lens 10 based on the input signal from the photographic lens zoom drive mechanism 10A. (Step # 19-7). If the current zoom position of the photographic lens 10 is not at the step zoom position (NO in step # 19-7), the overall control unit 40 is based on the output from the encoder of the optical finder zoom drive mechanism 70A and the current zoom position of the optical zoom finder 70. Is detected (step # 19-8), the electric motor 70 is driven, and the photographing lens is moved to the widest step zoom position based on the output from the encoder of the photographing lens zoom driving mechanism 10A, that is, the wide side. On the side, the focusing lens 10 is moved to a position corresponding to the focus adjustable range in FIG. 2 (step # 19-9). Then, the second image magnification calculator 42 calculates the actual image magnification α by the imaging lens 10 from the output of the encoder of the photographing lens zoom drive mechanism 10A, and the virtual image calculated in step # 19-8. An enlargement factor β is calculated from the magnification γf by the electronic zoom unit 44 (step # 19-10).
[0104]
Subsequently, the overall control unit 40 performs the focusing operation again with the focal length of the imaging lens 10 at that time by the distance measuring unit 62 (step # 19-11). The photometric unit 61 measures the subject luminance using the image data from the imaging unit 20 (photometric processing: step # 19-12), and based on the measured subject luminance, the aperture value of the imaging lens 10 and the imaging element 21 are measured. Exposure conditions such as the exposure time (charge accumulation time) are calculated (step # 19-13). Then, the overall control unit 40 extracts predetermined pixel data from the image captured by the imaging unit 20 using the enlargement ratio β calculated in step # 19-10, performs electronic zoom processing, and performs pixel processing. Data for thinning is performed to generate display image data (step # 19-14), and the display unit 50 displays the subject image on the display device 51 using the display image data (step # 19). -15), and returns to Step # 21.
[0105]
In the processing of steps # 19-8 to # 19-15 described above, since the subject image is not displayed on the display device 51 when the angle of view is set using the optical zoom finder, the optical zoom finder is used. By displaying the subject image with the angle of view set on the display device 51, it is possible to monitor the image that the user is currently shooting.
[0106]
When the photographing preparation process is completed in step # 19, the overall control unit 40 determines whether or not the shutter switch S2 is turned on (step # 21). If the shutter switch S2 is not turned on (NO in step # 21), the process returns to step # 17. If the shutter switch S1 is kept on, the above-described shooting preparation process is performed until the shutter switch S2 is turned on. Is repeated (the loop of steps # 17 to # 21). If the shutter switch S1 is turned off during that time (NO in step # 17), the process returns to step # 5, and the angle-of-view setting process using the electronic zoom finder or optical zoom finder described above is executed (steps # 5 to # 15). .
[0107]
When the shooting preparation process is completed and the shutter switch S2 is turned on (YES in step # 21), the “shooting process” is executed according to the flowchart shown in FIG. 15 (step # 23). That is, the overall control unit 40 drives the imaging unit 20 to perform an imaging operation (step # 23-1), and reads the image data from the image data memory 24 by the enlarged image data creation unit 43 (step # 23-2). Then, a predetermined range of pixel data is extracted from the image data in accordance with the already calculated enlargement ratio β (step # 23-3). Further, the overall control unit 40 creates pixel data that is insufficient by the pixel data interpolation unit 46 by interpolation processing (step # 23-4), and the pixel data that has been subjected to interpolation processing by the recording image data creation unit 47 The image data for recording is created by combining the data (step # 23-5). Then, the created recording image data is output to the recording unit 60 and recorded on a recording medium such as a memory card (step # 23-6). The series of photographing sequences is completed by recording the recording image data on the recording medium, and if necessary, the process returns to step # 5 to prepare for the next photographing.
[0108]
Here, when the optical viewfinder 70 is set, if attention is paid to the focal length (image magnification, angle of view) of the optical viewfinder 70 during the focusing operation, when the photographing lens 10 is driven for focusing, The associated lens of the optical viewfinder 70 is also driven, and as a result, there is a problem that the focal length (image magnification, field angle) set by the zoom switch operation changes. To solve this, (1) When the switch S1 is turned on, the photographing lens zoom driving mechanism 10A and the optical finder zoom starting mechanism 70A are disconnected in conjunction with each other so that the optical finder 70 is not driven during the focusing operation. The interlocking can be mechanical or electrical means using another actuator. In synchronism with the zoom switch operation, during the zoom operation, the photographing lens zoom drive mechanism 10A and the optical finder zoom drive mechanism 70A are interlocked, and when the zoom switch operation is finished, the photographing lens zoom drive mechanism 10A and the optical finder zoom are operated. It is good also as an aspect which interlock | cooperates with the drive mechanism 70A. (2) The focusing operation is not performed after the operation of the switch S1, but is a sequence performed after the operation of the switch S2. Then, after the focusing operation or shooting and data capture, the shooting lens 10 and the optical viewfinder 70 linked to the original position (focal length position set by the zoom switch operation) are driven. The angle of view can be visually recognized, and there is no problem if the operation is not slow even during focusing and shooting. (3) The photographic lens zoom drive mechanism 10A and the optical viewfinder zoom drive mechanism 70A are linked in a mechanical engagement manner having backlash. The driving force from the electric motor 71 is transmitted to the photographing lens 10 without backlash, and the driving force from the photographing lens 10 is transmitted to the optical viewfinder 70 with backlash. According to this aspect, when the moving direction of the photographic lens 10 during the focusing operation is opposite to the direction in which the angle of view is set, the optical finder 70 is not driven within a certain range (backlash amount), The angle of view will not change.
[0109]
By the way, in the shooting process shown in FIG. 15, the subject is imaged by the imaging unit 20, and the image for recording the angle of view set in the angle-of-view setting process in steps # 7 and # 9 is obtained by electronic zoom using the captured image. Is created and recorded on the recording medium, but the angle of view of the recording image may be corrected before recording on the recording medium. In this way, the photographer can determine the angle of view of the recorded image not only before photographing but also after photographing, so that the convenience of the angle-of-view setting operation for the photographed image is improved.
[0110]
FIGS. 16 and 17 are flowcharts of “imaging processing” in which the angle of view of a recording image can be corrected before recording on a recording medium. FIG. 18 is a block diagram of a digital camera in which the flowchart is implemented.
[0111]
The block configuration diagram shown in FIG. 18 is obtained by adding a maximum image capturing switch Sd and an enlargement ratio changing switch Se to the block configuration diagram of FIG. The maximum image capturing switch Sd is a switch that records image data read from the imaging unit 20 on a recording medium instead of recording image data. In the present embodiment, when an arbitrary angle of view is set by the zoom switches ST and SW, the recording image data is almost an electronic zoom image, but a captured image used by the user to create an electronic zoom image. May be recorded on a recording medium (for example, when an electronic zoom image is created by image processing with a personal computer after shooting and displayed on a display or output with a printer), the maximum image capture switch Sd The image data captured by the image capturing unit 20 in place of the recording image data (electronic zoom image) can be recorded on a recording medium.
[0112]
Therefore, when recording image data of a captured image on a recording medium instead of recording image data, the image is reproduced using the image data recorded on the recording medium using a digital camera or dedicated reproduction software. Thus, the calculated enlargement magnification β is recorded on the recording medium together with the image data so that an electronic zoom processed image can be output from an output device such as the display device 51 or a printer (not shown).
[0113]
The enlargement ratio change switch Se is a switch for changing the enlargement ratio β in the electronic zoom process. In the present embodiment, the enlargement ratio β can be changed from 1.0 to 1.5. The user can change the angle of view of the recording image created by the electronic zoom process by changing the enlargement factor β with the enlargement factor change switch Se. Then, after the user changes the enlargement factor β with the enlargement factor change switch Se to create a recording image with a desired angle of view, and determines the recorded image with the image determination switch Sa, the recording image is stored on the recording medium. Can be recorded.
[0114]
In the flowcharts shown in FIGS. 16 and 17, the “image data recording process” in step # 23-6 is changed to “monitor display process” (step # 23-6 ′) in the flowchart of FIG. A process (steps # 23-7 to # 23-15) for correcting the angle of view of the recording image is added after -6 ′.
[0115]
In the flowcharts shown in FIGS. 16 and 17, when image data for recording is created in step # 23-5, the image data is output to the display unit 50 and displayed on the monitor 51 (step # 23-). 6 '). This monitor display is for allowing the user to finally confirm the angle of view of the image recorded on the recording medium. Subsequently, the overall control unit 40 determines whether or not a recorded image has been determined based on an input signal from the image determination switch Sa (step # 23-8).
[0116]
When the recorded image is determined (YES in Step # 23-8), the overall control unit 40 further determines that the image data to be recorded on the recording medium is the image data of the captured image based on the input signal from the maximum image capture switch Sd. It is determined whether or not there is (step # 23-8). When the image data to be recorded on the recording medium is the image data of the captured image (YES in step # 23-8), the image is captured by the imaging unit 20. When the pixel data constituting the image is recorded on the recording medium (step # 23-10), the photographing process is terminated, and the image data to be recorded on the recording medium is the recording image data created by the electronic zoom process (NO in step # 23-8), the image data for recording is recorded on the recording medium (step # 23-9), and the photographing process is terminated.
[0117]
If the recorded image is not determined in step # 23-7 (NO in step # 23-7), the overall control unit 40 further determines whether or not the enlargement ratio β has been changed based on the input signal from the enlargement ratio change switch Se. (FIG. 17, step # 23-11). If the enlargement ratio β has been changed (YES in step # 23-11), the overall control unit 40 determines that the changed enlargement ratio β is not “1.0” (NO in step # 23-12). Predetermined pixel data is extracted from the image data of the image captured by the imaging unit 20 using the changed magnification factor β, electronic zoom processing is performed (step # 23-13), and further extracted pixel data Is thinned out to generate display image data (step # 23-14), and the monitor display on the display device 51 is updated using the display image data (step # 23-15). Return to -7.
[0118]
If the changed enlargement ratio β is “1.0”, the overall control unit 40 does not perform the electronic zoom process (step # 23-13 is skipped) and the image captured by the imaging unit 20 Display image data is generated by thinning out the image data (step # 23-14), and the monitor display on the display device 51 is updated using the display image data (step # 23-15). Return to # 23-7.
[0119]
If the enlargement ratio β is not changed in step # 23-11 (NO in step # 23-7), the overall control unit 40 further deletes the image based on the input signal from the image deletion switch Sb (captured image as a recording medium It is determined whether or not an instruction to not record is instructed (step # 23-16). If image deletion is not instructed (NO in step # 23-16), the process returns to step # 23-7. If image deletion is instructed (YES in step # 23-16), the image data memory 24 is temporarily stored. The stored image data of the captured image is deleted (step # 23-17), and the shooting process is terminated.
[0120]
In the description of the above embodiment, the photometry unit 61 and the distance measurement unit 62 measure the subject brightness or focus using the pixel data output from the imaging device 21 or the image data output from the imaging unit 20, respectively. Although the configuration is such that the state is detected, the present invention is not limited to this, and a unique photometric sensor and a range sensor may be used.
[0121]
FIG. 19 is a flowchart of “view angle setting process (2) by the optical zoom finder” showing another embodiment of the process of step # 9, and FIG. 20 shows another embodiment of the process of step # 15. It is a flowchart of "finder switching process II (2)".
[0122]
Steps # 9-1 to # 9-6 and # 9-8 to # 9-10 of “Viewing angle setting process using optical zoom finder (2)” correspond to “Viewing angle setting process using optical zoom finder” in FIG. Since it is the same, explanation is omitted. The overall control unit 40 is based on the output from the encoder of the optical finder zoom drive mechanism 70A of the optical zoom finder 70 while the zoom switch ST is kept on (loop of steps # 9-4 to # 9-6). Then, it is monitored whether or not the magnification changing lens of the optical zoom finder 70 has reached the tele end (step # 9-5), and if the zoom switch ST is turned off before the magnification changing lens reaches the tele end. (YES in Step # 9-6), the photographing lens 10 is driven to the nearest tele-side step zoom position to stop the driving of the electric motor 71, and the image magnification γf of the optical zoom finder 70 is held at the set magnification. (Step # 9-7 '), the process returns to Step # 9-3.
[0123]
When the zoom switch SW is turned on (YES in step # 9-3), the overall control unit 40 continuously drives the electric motor 71 to the wide side via the lens control unit 30 to widen the imaging lens 10. (Step # 9-8). The overall control unit 40 is based on the output from the encoder of the optical finder zoom drive mechanism 70A of the optical zoom finder 70 while the zoom switch SW is kept on (loop of steps # 9-8 to # 9-10). Then, it is monitored whether or not the lens for changing the magnification of the optical zoom finder 70 has reached the wide end (step # 9-9), and if the zoom switch SW is turned off before the lens for changing the magnification reaches the wide end. (YES in step # 9-10), the photographing lens 10 is driven to the closest wide-side step zoom position to stop the driving of the electric motor 71, and the image magnification γf of the optical zoom finder 70 is held at the set magnification. (Step # 9-11 '), the process returns to Step # 9-2.
[0124]
When the zoom switches ST and SW are turned off (NO in steps # 9-2 and # 9-3), the overall control unit 40 returns to step # 11, assuming that the angle of view setting by the zoom switches ST and SW has been completed. To do.
[0125]
In the finder switching process II (2) in FIG. 20, the overall control unit 40 calculates the actual image magnification α by the imaging lens 10 from the output of the encoder of the photographing lens zoom drive mechanism 10A by the second image magnification calculation unit 42 ( Step # 24-1). Further, the first image magnification calculator 41 calculates the virtual image magnification γ from the operation time of the zoom switch ST or SW immediately before the finder switching in the electronic zoom finder and the virtual zoom characteristic (step # 24-2).
[0126]
Subsequently, the overall control unit 40 continuously drives the electric motor 71 to the step zoom position where the image magnification γf of the optical zoom finder 70 is close to γ based on the encoder output of the optical finder zoom drive mechanism 70A, and the imaging lens. 10 is moved continuously (step # 24-3) and then stopped (step # 24-4). The process corresponding to the finder switching process I is the same.
[0127]
In the modified example, for the purpose of reducing the size and weight of the digital camera, the zoom lens type photographing lens 10 is adopted, and the image size smoothly changes during the zooming operation in both the electronic zoom finder and the optical zoom finder. However, this is a method that does not hinder field angle setting (image magnification setting) and shooting. That is, when the optical zoom finder 70 is selected, the zoom position at which the photographing lens 10 can be stopped is only the step zoom position at which the photographing lens 10 can be focused, and the stop is not permitted at other zoom positions, and the photographing is also performed. In this case, when the optical zoom finder is selected, the electric motor 71 that drives the photographic lens 10 and the optical zoom finder 70 is continuously driven according to the zoom operation of the photographer, and interlocked therewith. Thus, the optical zoom finder 70 is continuously driven to smoothly change the size of the angle of view. When the photographer sets the angle of view (image magnification), the photographing lens 10 and the optical zoom finder 70 are driven to the next step zoom position immediately after the photographing lens position when the photographer's zoom operation is completed. Accordingly, the electric motor 71 is driven, and after the photographing lens 10 and the optical zoom finder 70 are driven to the step zoom position, the energization to the electric motor 71 is stopped.
[0128]
In this way, the optical zoom finder 70 cannot be stopped at the angle of view (image magnification) that the photographer wants to stop, and the photographing cannot be performed, but the zoom operation originally has an overrun determined by inertia, Even if the photographer stops the zoom operation, the photographing lens 10 and the optical zoom finder 70 do not stop immediately. Accordingly, it is possible to set the angle of view (image magnification) intended by the photographer substantially without causing a sense of incongruity unless it deviates greatly from the range. In order to reduce discomfort, it is necessary to appropriately set the number and interval of step zoom positions that can be stopped with respect to the zoom range. This simplifies zooming, field angle setting, and shooting processing when the optical zoom finder is selected, and increases the operating speed and saves memory. In addition, there is a problem that the focal length (image magnification, field angle) set by the zoom switch operation changes during the focusing operation when the optical zoom finder 70 is set as shown in the first embodiment. Disappear.
[0129]
Processing when the electronic zoom finder is selected is the same as in the first embodiment. The finder switching process is the same as that in the first embodiment when the optical zoom finder is switched to the electronic zoom finder, but is as follows when the electronic zoom finder is switched to the optical zoom finder. When the optical zoom finder is used, the photographing lens 10 cannot be stopped except at the step zoom position. Therefore, when the zoom finder is switched, the optical zoom is performed to the virtual image magnification γ displayed on the electronic zoom finder immediately before the switching. An electric motor 71 for driving the photographic lens 10 and the optical zoom finder 70 to a step zoom position where the image magnification γf of the finder 70 is close (that is, the position of the photographic lens 10 stopped immediately before switching or the next step zoom position). Drive.
[0130]
In this way, when the zoom finder is switched, the angle of view (image magnification) that the photographer stopped when using the electronic zoom finder changes slightly. Therefore, there is a difference in the field of view rate, and there is a slight difference between the two image magnifications without performing an image magnification shift operation by switching the zoom finder. Therefore, as long as it does not deviate greatly from the range, there is little discomfort and it is possible to switch to the angle of view (image magnification) intended by the photographer. In order to reduce discomfort, it is necessary to appropriately set the number and interval of step zoom positions that can be stopped with respect to the zoom range.
[0131]
【The invention's effect】
As described above, according to the digital camera of the first aspect, the electronic zoom finder and the optical zoom finder are provided, and the imaging lens constituting the optical system of the electronic zoom finder is configured with a zoom focus type lens. By transmitting the driving force of the lens driving mechanism of the imaging lens to the optical zoom finder, the lens driving mechanism is shared as the lens driving mechanism of the optical zoom finder, and when the electronic zoom finder is set, the zoom switch When the optical zoom finder is set, the lens driving mechanism is driven stepwise so that the focal length of the imaging lens changes stepwise according to the operation. The lens drive mechanism of the imaging lens is adjusted so that the image magnification changes continuously. Since so as to continue to drive the can constitute a lens driving mechanism of the optical zoom finder and electronic zoom finder compact and small without compromising the continuous angle setting operation function. As a result, the digital camera including the optical zoom finder and the electronic zoom finder can be reduced in size and size.
[0132]
According to the second aspect of the present invention, when the finder is switched from the electronic zoom finder to the optical zoom finder during the setting of the angle of view, the image magnification of the optical finder is the same as the image magnification of the electronic zoom finder at the time of finder switching. As described above, the lens drive mechanism of the imaging lens is continuously driven, so that the subject image that the user can visually recognize even when the viewfinder is switched from the electronic zoom viewfinder to the optical zoom viewfinder during field angle setting. The angle is continuous, and the operability for setting the angle of view is not lowered.
[0133]
According to the third aspect of the present invention, when the finder is switched from the optical zoom finder to the electronic zoom finder during the setting of the angle of view, the image magnification of the subject image displayed by the electronic zoom finder is the optical zoom when the finder is switched. The focal length of the imaging lens was changed to the settable focal length of the imaging lens that is closest to the focal length corresponding to the image magnification of the optical zoom finder and less than the focal length so that it is the same as the image magnification of the viewfinder. Later, the subject was imaged by the imaging unit, and the captured image was enlarged at a predetermined magnification and displayed on the display unit, so that the viewfinder was switched from the optical zoom finder to the electronic zoom finder during field angle setting. Even in this case, the angle of view of the subject image viewed by the user is continuous and the operability of setting the angle of view is reduced as in the invention of claim 2. That there is no.
[0134]
According to the fourth aspect of the present invention, the lens driving mechanism of the imaging lens and the lens driving mechanism of the optical zoom finder can be shared, and downsizing and downsizing can be realized. Also, the release time lag can be minimized.
[Brief description of the drawings]
FIG. 1 is a diagram showing the configuration of an imaging lens and the positional relationship of each component lens group when the focal length is changed in an embodiment of a digital camera of the present invention.
FIG. 2 is a diagram illustrating a shape of a cam groove for step zoom in the imaging lens.
FIG. 3 is a diagram showing a block configuration of a digital camera according to the embodiment.
FIG. 4 is a diagram illustrating a relationship between a moving amount of a photographing lens with respect to an operation amount of a zoom switch when an electronic zoom finder is selected.
FIG. 5 is a diagram illustrating a relationship between a moving amount of a photographing lens with respect to an operation amount of a zoom switch when an optical zoom finder is selected.
FIG. 6 is a diagram illustrating a relationship between a focal length that an imaging lens can take when an electronic zoom finder is set, an image at each focal length, and an image at an intermediate focal length by electronic zoom.
FIG. 7 is a diagram illustrating zoom characteristics of an imaging lens when an electronic zoom finder is set.
FIG. 8 is a flowchart showing an imaging sequence of the digital camera in the present embodiment.
FIG. 9 is a flowchart of an angle-of-view setting process using an electronic zoom finder.
FIG. 10 is a continuation of the flowchart of FIG.
FIG. 11 is a flowchart of an angle-of-view setting process using an optical zoom finder.
FIG. 12 is a continuation of the flowchart of finder switching processing I.
FIG. 13 is a continuation of the flowchart of viewfinder switching processing II.
FIG. 14 is a continuation of the flowchart of the shooting preparation process.
FIG. 15 is a flowchart of imaging processing.
FIG. 16 is a flowchart of another shooting process.
FIG. 17 is a continuation of the flowchart of another photographing process.
FIG. 18 is a diagram illustrating a block configuration of a digital camera capable of executing another shooting process.
FIG. 19 is a flowchart showing a modified example of the angle of view setting process by the optical zoom finder.
FIG. 20 is a flowchart of viewfinder switching processing II (2).
[Explanation of symbols]
10: Imaging lens
10A: Zoom drive mechanism (component of lens drive mechanism)
11: First lens group
12: Second lens group
13: Third lens group
14: Fourth lens group
20: Imaging unit
21: Image sensor
22: A / D converter
23: Image processing unit
24: Image data memory
30: Lens control unit
40: Overall control unit (drive control means, field angle control means, focal length calculation means, focal length change means, enlargement ratio calculation means)
41: First image magnification calculator
42: Second image magnification calculator
43: Enlarged image data creation unit
44: Electronic zoom unit
45: Pixel data thinning part
46: Pixel data interpolation unit
47: Recording image data creation unit
50: Display section
51: Display device
52: Image data memory for display
60: Recording section
61: Metering unit
62: Distance measuring section
70: Optical zoom finder
70A: Zoom drive mechanism (finder drive mechanism, image magnification detection means)
71: Electric motor (component of lens driving mechanism)
72: Transmission member (component of lens driving mechanism and finder driving mechanism)
S1, S2: Shutter switch
SW, ST: Zoom switch
Sa: Image determination switch
Sb: Image deletion switch
Sc: finder setting switch (finder setting means)
Sd: Maximum image capture switch
Se: Enlargement ratio change switch

Claims (4)

A plurality of focal lengths that change stepwise are set in advance, and an imaging lens that can change the focal length stepwise to the plurality of focal lengths by changing the relative positions of the plurality of lens groups. An imaging unit that is provided at a predetermined position on the optical axis of the imaging lens and photoelectrically converts an image formed on the optical axis, and that outputs image data; and a focal length of the imaging lens A zoom switch for changing the distance between the longest focal length and the shortest focal length, and lens driving for changing the relative positions of the plurality of lens groups of the photographing lens in accordance with a signal from the zoom switch A digital camera comprising a mechanism,
A first image magnification calculation for calculating a virtual focal length and an image magnification from a virtual zoom characteristic curve connecting the longest focal length and the shortest focal length of the imaging lens and a time during which the zoom switch is operated continuously. A second image magnification calculation unit that calculates the magnification of an image actually formed on the light receiving surface of the imaging unit from the focal length of the imaging lens at the present time, and a virtual image by the first image magnification calculation unit An enlarged image data creating unit that creates enlarged image data obtained by enlarging image data output from the imaging unit using an image magnification and an actual image magnification obtained by the second image magnification calculating unit, and using the enlarged image data An electronic zoom finder having a display unit for displaying an image, and a subject optical image independently of the photographing lens, and moving the magnification changing lens to change the magnification to thereby change the object. An optical zoom finder capable of emitting a body light image to an eyepiece window, and a driving force generated by the lens driving mechanism is transmitted to a lens for changing the magnification of the optical zoom finder, thereby changing a focal position of the photographing lens. A finder drive mechanism that changes the magnification of the subject light image by moving the magnification changing lens in conjunction with the finder setting means for setting one of the electronic zoom finder and the optical zoom finder, When the electronic zoom finder is set, the lens driving mechanism is driven stepwise according to a signal from the zoom switch so that the focal length of the photographing lens changes stepwise, and the optical zoom finder Is selected so that the magnification of the subject light image emitted to the eyepiece window changes continuously. Serial digital camera, characterized in that a drive control means for continuously driven the lens driving mechanism in response to a signal from the zoom switch. 2. The digital camera according to claim 1, wherein when the viewfinder is switched from the electronic zoom finder to the optical zoom finder by the finder setting means at the time of setting an angle of view, the image magnification detecting means for detecting the image magnification of the optical zoom finder, A digital image display further comprising: an angle-of-view control means for driving the lens drive mechanism so that the image magnification detected by the image magnification detection means coincides with a virtual image magnification in the electronic zoom finder at the time of finder switching. camera. 3. The digital camera according to claim 2, wherein when the viewfinder is switched from the optical zoom finder to the electronic zoom finder by the finder setting means at the time of setting the angle of view, the optical at the time of finder switching detected by the image magnification detection means. A focal length calculation unit that calculates a step-shaped focal length that is closest to the focal length of the imaging lens corresponding to the image magnification of the zoom finder and that is less than or equal to the focal length, and the imaging lens; A focal length changing unit that changes a relative position of a plurality of lens groups to change a focal length to a focal length calculated by the focal length calculating unit, and a focal length of the imaging lens calculated by the focal length calculating unit And the image magnification at the time of finder switching detected by the image magnification detecting means to calculate an image enlargement ratio. And an enlargement ratio calculating means, and when the viewfinder is switched from the optical zoom finder to the electronic zoom finder by the finder setting means at the time of setting the angle of view, the enlarged image data creating unit is configured to capture the image by the focal length changing means. The image data output from the imaging unit after changing the focal length of the lens is enlarged by the enlargement factor calculated by the enlargement factor calculating means to create enlarged image data, and the display unit displays the enlarged image data. A digital camera characterized by using it to display an image. A plurality of focal lengths that change stepwise are set in advance, and an imaging lens capable of changing a focal length to the plurality of focal lengths by changing a relative position of a plurality of lens groups; and An imaging unit that is provided at a predetermined position on the optical axis of the imaging lens and photoelectrically converts an image formed on the optical axis, outputs an image data, and a focal length of the imaging lens A zoom switch for changing between the longest focal length and the shortest focal length; and a lens driving mechanism for changing the relative positions of the plurality of lens groups of the photographing lens in accordance with a signal from the zoom switch. A digital camera comprising:
A first image magnification calculation for calculating a virtual focal length and an image magnification from a virtual zoom characteristic curve connecting the longest focal length and the shortest focal length of the imaging lens and a time during which the zoom switch is operated continuously. A second image magnification calculation unit that calculates the magnification of an image actually formed on the light receiving surface of the imaging unit from the focal length of the imaging lens at the present time, and a virtual image by the first image magnification calculation unit An enlarged image data creating unit that creates enlarged image data obtained by enlarging image data output from the imaging unit using an image magnification and an actual image magnification obtained by the second image magnification calculating unit, and using the enlarged image data An electronic zoom finder having a display unit for displaying an image, and a subject optical image independently of the photographing lens, and moving the magnification changing lens to change the magnification to thereby change the object. An optical zoom finder capable of emitting a body light image to the eyepiece window, and a driving force generated by the lens driving mechanism is transmitted to a lens for changing the magnification of the optical zoom finder, on the optical axis of the photographing lens A finder drive mechanism that changes the magnification of the subject optical image by moving the magnification changing lens in conjunction with a change in position, and a finder setting that sets either the electronic zoom finder or the optical zoom finder And when the electronic zoom finder is set, the lens driving mechanism is driven stepwise according to a signal from the zoom switch so that the focal length of the photographing lens changes stepwise, When the optical zoom finder is selected, the signal from the zoom switch indicates the magnification of the optical zoom finder. And a drive control means for driving the lens driving mechanism so as to prohibit the stop at a magnification other than the step-like focal length even when the signal from the zoom switch is cut off. A digital camera characterized by that.

Images