JP2011193329A - Image pickup device - Google Patents

Abstract

An imaging apparatus that increases the optical zoom drive speed and does not show tracking blur.
A zoom driving unit that drives a zoom lens, a focus driving unit that drives a focus lens to adjust a focus state of a subject image as the zoom lens is driven, and a subject formed via an optical system An image pickup unit that picks up an image and generates image data, a display unit that outputs image data generated by the image pickup unit, an operation unit that specifies a zoom magnification, and an operation based on the zoom magnification specified by the operation unit A digital zoom control unit that controls to output a digital zoom image obtained by digitally zooming image data corresponding to the timing to the display unit, and an optical zoom control unit that controls the zoom drive unit to optically zoom based on the zoom magnification in conjunction with the digital zoom. When the optical zoom is completed, the digital zoom image is canceled to be output to the display unit. And a display control unit for controlling the over arm controller.
[Selection] Figure 1

Description

  The present invention relates to an imaging apparatus, and more particularly to an imaging apparatus capable of zoom adjustment.

    As with the camera disclosed in Patent Document 1, a camera having an optical zoom function has been widespread so that a user can adjust a shooting frame to a desired angle of view.

Japanese Patent Laid-Open No. 2004-064674

    In order to allow the user to quickly adjust the shooting frame to a desired angle of view, it is conceivable to increase the driving speed of the optical zoom. However, during optical zoom, the focus position is made to follow the zoom position so that the image being output is not blurred on the display screen. If the drive speed of the optical zoom is increased too much, the focus position cannot be followed. There was a possibility that a blurred image was output on the screen.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an imaging apparatus that does not show tracking blur while increasing the driving speed of the optical zoom.

  In order to solve the above problems, an imaging apparatus of the present invention is formed via an optical system that includes a zoom lens and a focus lens, a zoom drive unit that drives the zoom lens, and driving the zoom lens. A focus driving unit that drives the focus lens to adjust the focus state of the subject image, an imaging unit that captures the subject image formed via the optical system and generates image data, and image data generated by the imaging unit A display unit that outputs the image, an operation unit that accepts an operation by the user and designates the zoom magnification, and a digital zoom image obtained by digitally zooming image data corresponding to the operation timing based on the zoom magnification designated by the operation unit A digital zoom control unit that controls to output to the optical zoom unit, and an optical zoom based on the zoom magnification in conjunction with the digital zoom. Comprising an optical zoom control unit that controls the zoom drive unit to, after the optical zoom has been completed, a display control unit for controlling the digital zoom control unit to release the output to the display unit of the digital zoom image.

    According to the present invention, it is possible to provide an imaging device that does not show tracking blur while increasing the driving speed of the optical zoom.

Electrical configuration diagram of the digital camera 100 Rear view of digital camera 100 High-speed zoom mode flowchart Flow chart of interrupt processing due to panning and subject movement Image diagram for explaining zoom image display

[Embodiment 1]
The digital camera 100 according to Embodiment 1 can operate the optical zoom faster than usual without considering the focus tracking performance of zoom tracking.
Hereinafter, the configuration and operation of the digital camera 100 will be described.

[1. Constitution〕
Hereinafter, the configuration of the digital camera 100 will be described with reference to the drawings.

[1-1. Configuration of Digital Camera 100]
FIG. 1 is an electrical configuration diagram of the digital camera 100.
The digital camera 100 captures a subject image formed via the optical system 110 with the CCD image sensor 120.
The CCD image sensor 120 generates image data based on the captured subject image.
The image data generated by the imaging is subjected to various processes in an AFE (analog front end) 121 and an image processing unit 122.
The generated image data is recorded in the flash memory 142 or the memory card 140. The image data recorded in the flash memory 142 or the memory card 140 is displayed on the liquid crystal display 123 in response to an operation of the operation unit 150 by the user.

FIG. 2 is a rear view of the digital camera 100.
The digital camera 100 includes operation buttons such as a release button 170, a zoom lever 171 and a power button 172 on the upper surface. The digital camera 100 also includes a selection button 173, a determination button 174, and the like on the back.

  The optical system 110 includes a focus lens 111, a zoom lens 112, and the like. Although not shown, the optical system 110 may include an optical image stabilization lens OIS (Optical Image Stabilizer). The various lenses constituting the optical system 110 may be composed of any number of lenses or any number of groups.

  The focus lens 111 is used to adjust the focus state of the subject. The zoom lens 112 is used to adjust the angle of view of the subject.

The focus motor 115 is a drive unit that drives the focus lens 111 to move forward and backward along the optical axis in accordance with a control signal notified from the controller 130.
The zoom motor 116 is a drive unit that drives the zoom lens 112 to advance and retract along the optical axis in accordance with a control signal notified from the controller 130.
These driving means can be realized by a DC motor, a stepping motor or the like.

  The CCD image sensor 120 captures a subject image formed through the optical system 110 and generates image data. A large number of photodiodes are two-dimensionally arranged on the light receiving surface of the CCD image sensor 120. In addition, R, G, and B primary color filters are arranged in a predetermined arrangement structure corresponding to each photodiode. The light from the subject to be imaged passes through the optical system 110 and then forms an image on the light receiving surface of the CCD image sensor 120. The formed subject image is converted into color information classified into R, G, and B according to the amount of light incident on each photodiode. As a result, the entire image data indicating the subject image is generated. The CCD image sensor 120 generates image data of a new frame at a predetermined frame rate (for example, 30 frames / second). The CCD image sensor 120 adjusts the amount of exposure light by an electronic shutter operation in preview display. The image data generation timing and the electronic shutter operation of the CCD image sensor 120 are controlled by the controller 150. By displaying the image data as a through image on the display unit 170 one by one, the user can check the state of the subject on the display unit 170 in real time.

  The AFE 121 subjects the image data generated by the CCD image sensor 120 to noise suppression by correlated double sampling, amplification to the input range width of the AD converter 133 by an analog gain controller, and AD conversion by the AD converter. Thereafter, the AFE 121 outputs the image data to the image processing unit 122.

  The image processing unit 122 performs various processes on the image data output from the AFE 121. Examples of the various processes include, but are not limited to, smear correction, white balance correction, gamma correction, YC conversion process, electronic zoom process, compression process, and expansion process. The image processing unit 122 can execute a motion detection process. The motion detection process is a process for detecting the motion of the subject in each piece of image data acquired for each frame from a change in position of color information or luminance information. The motion detection of the present invention is not limited to the above-described method, and any known motion detection technique can be applied.

  The liquid crystal display 123 is provided on the back surface of the digital camera 100. The liquid crystal display 123 displays an image based on the image data processed by the image processing unit 122. The images displayed on the liquid crystal display 123 include a through image and a recorded image. The liquid crystal display 123 displays an image generated by the CCD image sensor 120 at regular intervals as a through image in substantially real time. The user can take a picture while confirming the composition of the subject by referring to the through image displayed on the liquid crystal display 123. The recorded image is an image recorded in the memory card 140 or the flash memory 142. The liquid crystal display 123 displays an image based on the already recorded image data in accordance with a user operation. In addition, the liquid crystal display 123 can display various setting conditions of the digital camera 100.

  The controller 130 controls the overall operation of the digital camera 100. The controller 130 includes a ROM that stores information such as programs, and a CPU that processes information such as programs. The ROM stores a program for controlling the overall operation of the digital camera 100 in addition to programs related to autofocus control (AF control) and automatic exposure control (AE control). The ROM does not have to be an internal configuration of the controller 130 and may be provided outside the controller 130.

  The buffer memory 124 is a storage unit that functions as a work memory for the image processing unit 122 and the controller 130. The buffer memory 124 can be realized by a DRAM (Dynamic Random Access Memory) or the like. The flash memory 142 is a storage unit that functions as an internal memory for recording image data and the like.

  The card slot 141 is a connection means that allows the memory card 140 to be attached and detached. The card slot 141 can connect the memory card 140 electrically and mechanically. The card slot 141 may have a function of controlling the memory card 120.

  The memory card 140 is an external memory provided with storage means such as a flash memory. The memory card 140 can record data such as image data processed by the image processing unit 122.

  The gyro sensor 160 includes vertical and horizontal sensors that detect movement of the digital camera 100 main body. The gyro sensor 160 detects the movement of the camera body such as pan and tilt based on information sensed in the vertical and horizontal directions. Then, the gyro sensor 160 notifies the controller 130 of the detected movement information of the camera body.

  The operation unit 150 is a general term for operation buttons and operation levers provided on the exterior of the digital camera 100, and accepts an operation by a user. For example, the release button 170, zoom lever 171, power button 172, selection button 173, determination button 174, etc. shown in FIG. When the operation unit 150 receives an operation by the user, the operation unit 150 notifies the controller 130 of various operation instruction signals.

  The release button 170 is a two-stage push button. When the release button 170 is pressed halfway by the user, the controller 130 executes an AF operation, an AE operation, or the like. When the release button 170 is fully pressed by the user, the controller 130 records image data captured at the timing of the pressing operation on the memory card 140 or the like as a recorded image.

  The zoom lever 171 for adjusting the angle of view notifies the controller 130 of an operation instruction signal for driving the zoom lens 112 when operated by the user. That is, when the zoom lever 171 is operated to the wide angle end, the controller 130 drives the zoom lens 112 so that the subject can be captured at a wide angle. Similarly, when the zoom lever 171 is operated to the telephoto end, the controller 130 drives the zoom lens 112 so that the subject can be captured at the telephoto end.

  The power button 172 is a push-type button for turning on / off the power supply to each part constituting the digital camera 100. When the power button 172 is pressed down by the user when the power is turned off, the controller 130 supplies power to each part constituting the digital camera 100 and activates it. When the power button 172 is pressed by the user when the power is turned on, the controller 130 stops the power supply to each unit.

  The selection button 173 is a push button provided in the up / down / left / right directions. The user can select various condition items displayed on the liquid crystal display 123 by pressing any direction of the selection button 173.

  The decision button 174 is a push button. When the determination button 174 is pressed by the user while the digital camera 100 is in the shooting mode or the playback mode, the controller 130 displays a menu screen on the liquid crystal display 123. The menu screen is a screen for setting various conditions for shooting / playback. When the determination button 174 is pressed when a setting item of various conditions is selected, the controller 130 finalizes the setting of the selected item. The digital camera 100 according to the first embodiment has a normal shooting mode and a high-speed zoom shooting mode as shooting modes. The normal shooting mode is a general mode in which the user can adjust the angle of view while viewing the through image. Details of the high-speed zoom shooting mode will be described later. When the digital camera 100 is in the shooting mode, the user can select whether to set the normal shooting mode or the high-speed zoom shooting mode from the menu screen displayed on the liquid crystal display 123. .

[1-2. Correspondence with the present invention]
The focus lens 111 is an example of the focus lens of the present invention. The zoom lens 112 is an example of the zoom lens of the present invention. The zoom motor 116 is an example of a zoom drive unit of the present invention. The focus motor 115 is an example of the focus drive unit of the present invention. The CCD image sensor 120 is an example of an imaging unit of the present invention. The liquid crystal display 123 is an example of the display unit of the present invention. The zoom lever 171 is an example of the operation unit of the present invention. The controller 130 is an example of a digital zoom control unit of the present invention. The controller 130 is an example of the optical zoom control unit of the present invention. The controller 130 is an example of a display control unit. The controller 130 is an example of a panning determination unit of the present invention. The controller 130 is an example of a motion determination unit of the present invention. The digital camera 100 is an example of an imaging apparatus of the present invention.

[2. Operation)
The digital camera 100 executes optical zoom drive control at high speed while outputting a digital zoom image to the display screen. When the optical zoom driving is completed, the digital camera 100 cancels the output of the digital zoom image to the display screen. The operation of the digital camera 100 in the high-speed zoom shooting mode will be described below with reference to FIGS. FIG. 3 is a flowchart of the high-speed zoom shooting mode of the digital camera 100 according to the first embodiment. First, the outline of the operation in the high-speed zoom shooting mode will be described with reference to FIG.

  When the power button 172 is pressed by the user, the digital camera 100 is turned on. At this time, the controller 130 supplies power to each unit constituting the digital camera 100. In addition, the controller 130 completes the initialization operation of the optical system 110 and the CCD image sensor 120 so that the through image is displayed on the liquid crystal display 123. FIG. 5A shows an image view of a through image displayed on the liquid crystal display 123. In FIG. 5A, the subject, the zoom bar, and the zoom magnification are displayed on the liquid crystal display 123. FIG. 5A shows an example in which the zoom magnification is 1. When the through image display on the liquid crystal display 123 is started, the user can adjust the angle of view by operating the zoom lever 171 while confirming the shooting frame.

  When the user operates the zoom lever 171, the controller 130 is notified that the zoom operation has been performed, and the controller 130 detects a zoom magnification change. The controller 130 starts digital zoom processing based on the changed zoom magnification (S300). When the zoom process is started, the controller 130 stores the through image before the magnification change in the buffer memory 124. The image processing unit 122 performs digital zoom processing on the through image according to the zoom magnification. The digitally zoomed image is displayed on the liquid crystal display 123 (S301). FIG. 5B shows an image diagram of a digital zoom image displayed on the liquid crystal display 123. FIG. 5B shows an example in which the zoom magnification is 5 times. As described above, in step S300 to step S301, the liquid crystal display 123 displays a through image digitally zoomed based on the zoom magnification designated by the user.

  When the shooting frame is adjusted to a desired angle of view, the user ends the operation of the zoom lever 171. At this time, the controller 130 determines whether the user determines the angle of view and completes the zoom operation (S302). When the controller 130 determines that the zoom operation has not been completed, that is, the user is operating the zoom lever 171 (NO in S302), the operations from step S300 to step S302 are repeated.

  On the other hand, when the controller 130 determines that the zoom operation is completed, that is, the user has finished operating the zoom lever 171 (Yes in S302), the controller 130 stores the latest image data stored in the buffer memory 124. The digitally zoomed image (still image) based on the designated zoom magnification is displayed on the liquid crystal display 123. Then, based on the determined zoom magnification, the controller 130 drives the zoom motor 116 to move the zoom lens 112 to a desired position (S303). At this time, the controller 130 performs tracking control for causing the focus lens 111 to follow the movement of the zoom lens 112 (S303). This tracking control is performed so that the display screen is not blurred during the optical zoom. However, in the high-speed zoom shooting mode, the zoom lens 112 is driven at a higher speed than in the normal shooting mode in order to give priority to being able to quickly adjust the angle of view desired by the user. Therefore, the movement of the focus lens 11 cannot follow the zoom lens 112 that moves at high speed, and the display screen may be blurred. However, in step S303, since the liquid crystal display 123 displays a digitally zoomed still image, the user does not recognize blur caused by tracking control. As a result, the digital camera 100 can achieve both high-speed zoom driving that quickly adjusts the angle of view desired by the user and avoiding the problem of blurring output on the display screen.

  Subsequently, the controller 130 determines whether the zoom lens 112 and the focus lens 111 following the zoom lens 112 have been moved to a desired position (S304). That is, the controller 130 determines whether or not the optical zoom driving is finished. When determining that the zoom lens 112 and the focus lens 111 have not been moved to the desired positions (No in S304), the controller 130 continues the optical zoom drive. The controller 130 repeats the operations from step S303 to step S304 until the focus lens 111 and the zoom lens 112 are completely moved to desired positions. Since the focus lens 111 is driven following the movement of the zoom lens 112, the movement completion is slightly delayed from the movement completion of the zoom lens 112. Accordingly, if the display of the digital zoom image is canceled and the through image display is started when the movement of the zoom lens 112 is completed, the movement of the focus lens 111 is not yet completed, and the user may visually recognize the blur. There is. Therefore, after the movement of the focus lens 111 following the movement of the zoom lens 112 is completed, the controller 130 cancels the display of the digital zoom image and starts the through image display (S305). FIG. 5C shows an image view of the through image displayed on the liquid crystal display 123. FIG. 5C shows an example in which the zoom magnification is 5 times.

  The controller 130 performs interrupt control based on panning and subject movement while performing the processes of steps S303 to S304. FIG. 4 shows a flowchart of interrupt control by panning and subject movement.

  The controller 130 monitors the panning of the camera body and the movement of the subject while performing the processes of S303 to S304 (S400). When the controller 130 detects panning and movement of the subject (Yes in S400), the controller 130 cancels the digital zoom image display in order to give priority to the angle of view adjustment by the user even during the optical zoom drive. The through image display is started (S401). At this time, the controller 130 continues the optical zoom in the middle of driving, but sets the zoom speed slower than that in the high-speed zoom shooting mode so that the tracking blur is not visually recognized by the user.

  When the controller 130 does not detect panning and subject movement during the processes of steps S303 to S304 (No in S400), the controller 130 does not execute the interrupt control shown in FIG. 4 and continues the processes of steps S303 to S304. To do.

As described above, the digital camera 100 executes optical zoom drive control at a high speed while outputting a digital zoom image to the display screen. When the optical zoom driving is completed, the digital camera 100 cancels the output of the digital zoom image to the display screen. As a result, the digital camera 100 can achieve both high-speed zoom driving that quickly adjusts the angle of view desired by the user and avoiding the problem of blurring output on the display screen. The digital camera 100 cancels the digital zoom image display and starts the through image display when the panning or the movement of the subject is detected even during the optical zoom drive in the high-speed zoom shooting mode. Thereby, the digital camera 100 can prioritize the angle of view adjustment by the user when the panning or the movement of the subject is detected.
[2. Other Embodiments]
The present invention is not limited to the first embodiment, and various embodiments are conceivable. Hereinafter, other embodiments of the present invention will be described together.

  In the first embodiment, the CCD image sensor 120 has been described as an example of the imaging unit, but the present invention is not limited to this. That is, other image pickup devices such as a CMOS image sensor and an NMOS image sensor can be applied to the present invention.

  Although the liquid crystal display 123 has been described as an example of the display unit in the first embodiment, the present invention is not limited to this. That is, even other display devices such as an organic EL display can be applied to the present invention.

  In the first embodiment, the zoom lever 171 is a center-position self-returning lever having a wide-angle end and a telephoto end, but the present invention is not limited to this. That is, as long as it has a wide-angle end and a telephoto end, a switch-type operation unit may be used, or even a touch panel input arranged on the liquid crystal display 123 can be applied to the present invention.

  As described above, according to the present invention, a digital camera capable of zooming at high speed can be provided.

  The present invention is not limited to the implementation on the digital camera 100. In other words, the present invention can be applied to an imaging apparatus capable of zoom adjustment such as a movie camera or a mobile phone with a camera.

100 Digital Camera 111 Focus Lens 112 Zoom Lens 120 CCD Image Sensor 121 AFE (Analog Front End)
122 Image processing unit 123 Liquid crystal display 124 Buffer memory 130 Controller 140 Memory card 141 Card slot 142 Flash memory 150 Operation unit 160 Gyro sensor 170 Release button 171 Zoom lever 172 Power button 173 Select button 174 Enter button

Claims (3)

An optical system including a zoom lens and a focus lens;
A zoom drive unit for driving the zoom lens;
A focus driving unit that drives the focus lens to adjust a focus state of a subject image formed through the optical system in accordance with the driving of the zoom lens;
An imaging unit that captures a subject image formed through the optical system and generates image data;
A display unit that outputs image data generated by the imaging unit;
An operation unit for accepting an operation by a user and specifying a zoom magnification,
A digital zoom control unit that controls to output a digital zoom image obtained by digitally zooming image data corresponding to an operation timing to the display unit based on the zoom magnification specified by the operation unit;
In conjunction with the digital zoom, an optical zoom control unit that controls the zoom drive unit to optically zoom based on the zoom magnification;
A display control unit that controls the digital zoom control unit to cancel the output of the digital zoom image to the display unit after the optical zoom is completed;
An imaging apparatus comprising: A panning determination unit;
When the display control unit determines panning, the display control unit cancels output of the digital zoom image to the display unit.
The imaging device according to claim 1. It further includes a movement determination unit that determines the movement of the subject,
The display control unit cancels output of the digital zoom image to the display unit when the movement of the subject is determined;
The imaging device according to claim 1.

Images