JP2013098905A - Imaging device and control method of imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device capable of easily finding a photographing subject present around outside the angle of view of a photographing optical system by including a zoom photographing assist function interlocked with the zoom magnification of the photographing optical system.SOLUTION: An imaging device 10 comprises a photographing optical system 11 with a zoom lens and an auxiliary optical system 12 separate from the photographing optical system 11. The auxiliary optical system 12 has a digital zooming function. The auxiliary optical system 12 has a digital zoom circuit 51 for setting a digital zoom magnification corresponding to the optical zoom position of the photographing optical system 11 when the photographing optical system 11 is performing zoom operation.

Description

  The present invention relates to an imaging optical system, an imaging apparatus having an auxiliary optical system different from the imaging optical system, and an imaging apparatus control method.

  With a digital still camera equipped with a long focal length photographing optical system, a far object can be photographed large, but in this case, the angle of view becomes narrow. For this reason, in the live view displayed through the photographing optical system, it is difficult to find the target subject and keep it within the angle of view.

  Therefore, a digital still provided with an auxiliary optical system having a wider angle of view than the photographing optical system (this auxiliary optical system is provided with a dedicated image sensor) separately from the photographing optical system. The camera is known. In such a digital still camera, an auxiliary optical system is used to input an image with a wider angle of view than the shooting optical system, and when the live view of the shooting optical system is displayed on the liquid crystal screen, the auxiliary optical system Can be displayed on the LCD screen in picture-in-picture format. Such a display makes it easy to find a subject outside the angle of view of the imaging optical system, so that it is possible to assist the user in determining the shooting composition by the zoom operation (hereinafter referred to as the picture-in- The display in the picture format is referred to as “zoom photographing auxiliary function”).

  Also, in a compound eye camera for 3D shooting, grasp the positional relationship between the wide side and the tele side when performing wide (short-distance focus) with the right imaging system and tele (long-distance focus) with the left imaging system. For the purpose, it has been proposed to display the frame size as guidance or to display the wide-side video in the picture-in-picture format on the tele-side video (see, for example, Patent Document 1).

  However, in Patent Document 1 and the conventional zoom shooting assist function, the angle of view of an optical system having a wider angle of view (the wide-side imaging system, the second optical system described above) depends on the subject to be searched, In some cases, the angle of view of the optical system is not appropriate. For example, if the subject is a small bird and the angle of view is so wide that it is difficult for the image from the auxiliary optical system to visually recognize the bird, it will not be suitable for searching for the subject. In the zoom shooting assist function, when the picture from the auxiliary optical system is displayed in the picture-in-picture format for simultaneous display with the live view from the photographing optical system, the display area is small, and it is further possible to visually recognize a small subject. It becomes difficult.

  On the other hand, if the angle of view of the auxiliary optical system is designed to be narrow, the image from the auxiliary optical system can be confirmed only in a narrow range around the angle of view of the shooting optical system, and from a wider range outside the angle of view of the shooting optical system. The function of searching for a subject is impaired.

  In an imaging apparatus equipped with a zoom shooting assist function, the shooting optical system is a high-power zoom lens because of cost and the like, and the auxiliary optical system often uses a fixed focus lens. When the angle becomes narrower due to zooming, the angle of view of the image captured by the auxiliary optical system does not change, so the angle of view of the image capturing optical system and the auxiliary optical system are too different. There is a problem that it is difficult to find a subject from outside.

  The technique of Patent Document 1 has a problem that it is difficult to find a small subject on the wide side when the difference in display magnification between the wide side and the tele side becomes too large.

  An object of the present invention is to appropriately capture an image from the auxiliary optical system in accordance with the zoom magnification of the imaging optical system in an imaging apparatus having the imaging optical system and an auxiliary optical system having a wider angle of view than the imaging optical system. An object of the present invention is to provide an imaging apparatus capable of making it easier for a user to find a target subject from an image from an auxiliary optical system and a method for controlling the imaging apparatus by providing a zoom photographing auxiliary function for displaying at a wide angle of view.

  In order to solve the above-described problem, an imaging apparatus according to claim 1 is an imaging apparatus including a first optical system having a zoom lens and a second optical system different from the first optical system. The second optical system is set to a digital zoom magnification corresponding to the optical zoom position of the first optical system, and the imaging device is based on a subject image formed by the second optical system. It is characterized by comprising display means for displaying the image data by digital zooming with the digital zoom magnification.

  According to the present invention, in an imaging apparatus having a photographing optical system and an auxiliary optical system having a wider angle of view than the photographing optical system, an image from the auxiliary optical system is appropriately selected according to the zoom magnification of the photographing optical system. By providing a zoom shooting assist function that displays images with a wide angle of view, the user can easily find the target subject from the video from the assist optical system.

1 is an external perspective view of an imaging apparatus having a zoom shooting assist function. It is a system block diagram of a general imaging device. It is a figure explaining the internal structure of the optical system for imaging | photography. It is a figure explaining the internal structure of an auxiliary optical system. It is a block diagram which shows the internal structure of a display control part. It is a figure which shows the example of a display of a zoom assist monitor. It is a figure explaining the zoom lens position detection mechanism of the imaging optical system. It is the figure which showed the output relationship of a rotary encoder and a photo interrupter. It is a figure which shows the variable for control used for control of the imaging optical system, and its table. It is the flowchart explaining the control operation of the reference point detection of a zoom lens. (A) is a flowchart explaining the operation of the zoom operation control, and (B) is a flowchart explaining the operation of the rotary encoder pulse interrupt control. It is a flowchart explaining operation | movement of the confirmation process of a zoom position. It is a figure which shows a zoom position table. 1 is a system block diagram of an imaging apparatus according to Embodiment 1. FIG. It is a figure which shows the variable for zoom control in the imaging device of FIG. 14, and its table. It is a figure which shows a zoom position table. (A) is a flowchart explaining the operation of the zoom operation control, and (B) is a flowchart explaining the operation of the rotary encoder pulse interrupt control. FIG. 6 is a diagram illustrating zoom control variables and a table thereof in the imaging apparatus according to the second embodiment. (A) is the figure which showed the example of a screen for an operator to select assist_magn_rate, (B) is a flowchart which shows the procedure of selection. It is a flowchart which shows operation | movement at the time of selecting a zoom imaging | photography auxiliary | assistant magnification ratio. It is a figure explaining the magnification setting control in a digital zoom circuit magnification setting at the time of zoom control.

  Embodiments of the present invention will be described below with reference to the drawings.

Example 1
First, a general configuration of an imaging apparatus having a zoom shooting assist function will be described with reference to FIGS.

  FIG. 1 is an external perspective view of an imaging apparatus 10 having a zoom photographing assist function. The imaging device 10 includes a photographing optical system 11 and an auxiliary optical system 12 as a second optical system.

  The photographing optical system 11 uses a high-magnification zoom lens, and is used for live view and image storage for storage. A fixed focus lens 31 (see FIG. 4) is used for the auxiliary optical system 12. This auxiliary optical system 12 inputs a video with a wider angle of view and performs a live view display in a picture-in-picture format when performing live view display with a high-magnification zoom using the imaging optical system 11. Therefore, the photographing optical system 11 is provided so as to be able to search for a subject from outside the field angle range captured.

  FIG. 2 is a system block diagram of a general imaging apparatus 10. As shown in FIG. 1, the imaging apparatus 10 includes a photographing optical system 11 and an auxiliary optical system 12, and each of the optical systems 11 and 12 includes a video I / F 13 that transmits an input video, and an optical. Each is connected to the image processing chip 15 via a control I / F 14 for controlling the system. The image processing chip 15 has a built-in control microcomputer and controls peripheral devices.

  The video I / F 13 transmits a digital signal of an input video, and LVDS (Low Voltage Differential Signaling) or the like is used. The control I / F 14 transmits a control command to the lens control device of the optical system or the controller of the imaging device, and a 3-wire serial or the like is used. The video signal input from the optical system is subjected to format conversion such as YUV conversion, image quality correction such as gamma correction, and noise reduction in the image processing chip 15. The video processed by the image processing chip 15 is sent to the display control unit 16 via the data bus and displayed on an LCD (Liquid Crystal Display) 17.

  The image processing chip 15 is connected with an external memory 18 and an operation unit 19. The external memory 18 is a detachable flash memory such as an SD memory card, and stores captured images. Further, the operation unit 19 accepts an operator's button operation during imaging.

  FIG. 3 is a diagram showing the internal configuration of the photographing optical system 11. The photographing optical system 11 includes an objective lens 21, zoom lenses 22 and 23, a zoom lens drive mechanism 24, a zoom lens position detection mechanism 25, an image sensor 26, and an intermediate lens 27 disposed between the zoom lenses 22 and 23. ing.

  The zoom lenses 22 and 23 are lenses for changing the focal length of the lens. The zoom lens driving mechanism 24 is for driving (moving) the zoom lenses 22 and 23 in parallel with the optical axis, and includes a motor, a rotary encoder for detecting the amount of movement of the zoom lenses 22 and 23, and the like. . The zoom lens position detection mechanism 25 is for detecting the reference position of the zoom lens 23 and incorporates a sensor such as a photo interrupter. The image sensor 26 is a CMOS image sensor or a CCD image sensor, and converts an image formed by each lens into a digital signal. The screw threads 24B and 24C formed at two positions of the rotation shaft 24A provided in the zoom lens driving mechanism 24 are opposite to each other, and when the rotation shaft 24A rotates, the zoom lenses 22 and 23 approach each other. Or move away.

  FIG. 4 is a diagram showing the internal configuration of the auxiliary optical system 12. The auxiliary optical system 12 includes a fixed focus lens 31, a lens 32, and an image sensor 33 including a CMOS. Unlike the photographing optical system 11 of FIG. 3, the auxiliary optical system 12 is not provided with a zoom mechanism.

  FIG. 5 is a block diagram showing an internal configuration of the display control unit 16. The display control unit 16 includes a VRAM1 35, a VRAM2 36, and a video composition unit 37. In this way, the display control unit 16 has a two-sided VRAM composed of the VRAM1 35 and the VRAM2 36 that are bus-connected to the image processing chip 15 (see FIG. 2). The video is synthesized and the synthesized video is output to the LCD 17.

  FIG. 6 shows a display example on the zoom assist monitor (LCD 17). A live view 41 of a video input from the photographing optical system 11 and a live view 42 of a video input from the auxiliary optical system 12 are combined in a picture-in-picture format and displayed on the LCD 17. In this case, the operator of the imaging apparatus 10 can simultaneously view the video being shot (that is, the live view 41) and the surrounding video (that is, the live view 42) that is shot with a wider angle of view. Therefore, by checking the video of the live view 42, it is possible to easily find a subject that is outside the angle of view of the photographing optical system 11.

  FIG. 7 is a diagram illustrating the zoom lens position detection mechanism 25 of the photographing optical system 11. The zoom lens 23 can detect the amount of movement of the zoom lens 23 by a rotary encoder 43 built in the zoom lens drive mechanism 24, and the zoom lens 23 can be detected by a photo interrupter 44 built in the zoom lens position detection mechanism 25. Detect if it is in the reference position. Then, the zoom lens 23 moves in the directions of arrows A1 and A2 by driving the zoom lens driving mechanism 24 based on the reference position detected by the photo interrupter 44.

  FIG. 8 is a diagram showing an output relationship between the rotary encoder 43 and the photo interrupter 44. In FIG. 7, when the zoom lens 23 moves in the A1 and A2 directions, pulses are output from the rotary encoder 43 at a constant cycle as shown in FIG. 8A according to the amount of movement of the zoom lens 23. When the zoom lens 23 passes the reference position, one pulse is output from the photo interrupter 44 as shown in FIG. In this case, as shown in FIG. 8C, the number of pulses when passing through the reference position is counted as 0, and thereafter, the number of pulses is added and stored every time the pulse is output from the rotary encoder 43. The position of the lens 23 can be recorded. As a result, when the zoom lens 23 moves, the focal length changes in proportion to time as shown in FIG.

  FIG. 9 shows control variables used for controlling the photographing optical system 11 and a table thereof. Here, position_cnt indicates that the position from the reference point of the zoom lens group of the imaging optical system is held as the number of pulses, and position_table indicates the zoom lens position and focal length indicated by position_cnt of the imaging optical system. In the table, zoom_position indicates the current focal length of the imaging optical system.

  FIG. 10 is a diagram for explaining the control operation for detecting the reference point of the zoom lens. As shown in FIG. 10A, the motor of the zoom lens driving mechanism 24 is driven (step S11), and it waits until the detection that the zoom lens 23 has reached the reference position, that is, the reference point detection (step S12). Then, the motor is stopped (step S13).

  As shown in FIG. 10B, when the zoom lens 23 is operated by the start of motor driving in step S11 and the zoom lens 23 passes the reference position, the zoom lens position detection mechanism 25 generates a reference point detection interrupt. Occur. When this reference point detection interrupt is generated, position_cnt is cleared to 0 (step S14).

  FIG. 11A is a flowchart illustrating an operation in zoom operation control. In FIG. 11A, when the photographer presses the zoom button to start the zoom operation, the type of the zoom button is detected (step S20), and it is further determined whether or not the zoom-up button is pressed (step S21). When the zoom-up button is pressed (that is, when zooming up), the motor of the zoom lens driving mechanism 24 starts to be driven to the tele side (step S22), and when the zoom-up button is not pressed (that is, zooming down) In the case of (1), driving of the motor is started on the wide side (step S23).

  When the process of driving the motor of the zoom lens driving mechanism 24 to the tele side or the wide side is completed, the zoom button driving mechanism 24 is stopped after waiting for the zoom button opening interruption (step S24).

  FIG. 11B is a flowchart for explaining the operation in the rotary encoder pulse interrupt control. The rotary encoder pulse interruption is generated by the operation of the motor of the zoom lens driving mechanism 24, detects the type of the zoom button (step S26), and further determines whether or not the zoom up button is pressed (step S27). When the zoom up button is pressed (that is, when zooming up), position_cnt is counted up (step S28), and when the zoom up button is not pressed (that is, when zooming down), position_cnt is counted down. (Step S29).

  By controlling in this way, a value corresponding to the current lens position can be stored in position_cnt.

  FIG. 12 is a flowchart for explaining the operation in the zoom position confirmation process. The zoom_position can be acquired by subtracting a pre-designed position_cnt and focal length correspondence table position_table (step S30).

  FIG. 13 shows a zoom position table. The focal length designed in advance is held as a position_table as shown in FIG. 5B according to the value of position_cnt as shown in FIG.

  Here, the known focal length is displayed on the LCD 17 to be shown to the operator as shooting information, stored as shooting information recording information, and used for image processing parameters.

  Next, the characteristic part of a present Example is demonstrated. In the present embodiment, as shown in FIG. 14, a digital zoom circuit 51 is interposed between the auxiliary optical system 12 and the image processing chip 15. The digital zoom circuit 51 is connected to the image processing chip 15 via the video I / F 52 and the control I / F 53. The auxiliary optical system 12 is connected to the image processing chip 15 only through the control I / F 14.

  The imaging optical system 11 is connected to the image processing chip 15 via the video I / F 13 and the control I / F 14 as in the case of FIG. The display control unit 16, the LCD 17, the external memory 18, and the operation unit 19 are the same as in the case of FIG.

  FIG. 15 shows variables for zoom control and a table thereof in the image pickup apparatus 10 of FIG. Here, position_cnt indicates that the position from the reference point of the zoom lens group of the imaging optical system is held as the number of pulses, and position_table indicates the zoom lens position and focal length indicated by position_cnt of the imaging optical system. Zoom_position indicates the current focal length of the imaging optical system, and zoom_assist_magn_table indicates a position_cnt and a display magnification table for the corresponding zoom imaging assist function.

  FIG. 16 shows a zoom position table. The value of position_cnt in FIG. 16A is the same as the value of position_cnt in FIG. 13A, and the value of position_table in FIG. 16B is the same as the value of position_table in FIG. The difference from FIG. 13 is that zoom_assist_magn_table that can set the zoom magnification of the zoom photographing assist function for each position_cnt is added.

  Next, the operation of the zoom operation in the imaging apparatus 10 shown in FIG. 14 will be described.

  FIG. 17A is a flowchart illustrating an operation in zoom operation control. The control in FIG. 17A is the same as that in FIG. That is, when the photographer presses the zoom button to start the zoom operation, the type of the zoom button is detected (step S40), and it is further determined whether or not the zoom up button is pressed (step S41). When the zoom up button is pressed (that is, when zooming up), the motor of the zoom lens driving mechanism 24 starts to be driven to the tele side (step S42), and when the zoom up button is not pressed (that is, zooming down). In the case of (1), the motor starts to be driven to the wide side (step S43).

  When the process of driving the motor of the zoom lens driving mechanism 24 to the tele side or the wide side is finished, the zoom button driving mechanism 24 is stopped (step S45) after waiting for the zoom button opening interruption (step S44).

  FIG. 17B is a flowchart for explaining the operation in the rotary encoder pulse interrupt control. The processes in steps S46 to S49 in FIG. 17B are the same as the processes in steps S26 to S29 in FIG. That is, the rotary encoder pulse interruption is generated by the operation of the motor of the zoom lens driving mechanism 24, detects the type of the zoom button (step S46), and further determines whether or not the zoom up button is pressed (step S47). . When the zoom up button is pressed (that is, when zooming up), position_cnt is counted up (step S48), and when the zoom up button is not pressed (that is, when zooming down), position_cnt is counted down. (Step S49).

  In this embodiment, after the process of step S48 or the process of step S49, a zoom position confirmation process is performed for the pulse interrupt of the rotary encoder (step S50), and then the digital zoom circuit magnification is set (step S51). .

  According to the present embodiment, by adding the processing in step S51, the live view 42 (see FIG. 6) of the auxiliary optical system is displayed in an enlarged (or reduced) manner according to the zoom position of the photographing optical system.

  In other words, by adding an image processor for performing display magnification enlargement with respect to the input from the image sensor of the auxiliary optical system, according to the zoom position and presetting of the photographing optical system, in picture-in-picture display The magnification of the image data from the auxiliary optical system can be changed.

  Therefore, in the video from the auxiliary optical system, the user can easily find the target subject, and as a result, the shooting composition can be easily determined by the zoom operation of the imaging optical system.

Example 2
Next, Example 2 will be described. FIG. 18 illustrates variables for zoom control and a table thereof in the imaging apparatus according to the second embodiment. Here, position_cnt indicates that the position from the reference point of the zoom lens group of the imaging optical system is held as the number of pulses, and position_table indicates the zoom lens position and focal length indicated by position_cnt of the imaging optical system. , Zoom_position indicates the current focal length of the optical system for imaging, assist_magn_rate indicates the display magnification ratio of the optical system for imaging and the zoom imaging auxiliary function, and assist_magn indicates the magnification that is applied to the digital zoom circuit of the auxiliary optical system. ing.

  Zoom_assist_magn_table1 is position_cnt and the corresponding zoom magnification assist function display magnification table 1 (for assist_magn_rate = 0.25), zoom_assist_magn_table2 is position_cnt and the corresponding zoom magnification assist function display magnification table 1 (assist_magn_rate = 0.5) Zoom_assist_magn_table3 indicates position_cnt and the corresponding zoom magnification assist function display magnification table 1 (for assist_magn_rate = 0.75).

  In the present embodiment, as described above, having an assist_magn_rate value selected by the operator and having a plurality of zoom_assist_magn_tables. These two points are greatly different from those in the first embodiment. assist_magn_rate is used to hold the ratio of the zoom magnification between the imaging optical system and the auxiliary optical system.

  FIG. 19A is a diagram showing an example of a screen for the operator to select assist_magn_rate, and FIG. 19B is a flowchart showing the selection procedure. As shown in the upper diagram of FIG. 19A, a zoom assist magnification selection menu is displayed on the screen (step S60). Then, when the operator clicks the zoom shooting auxiliary magnification ratio on the screen, as shown in the lower diagram of FIG. 19A, the zoom shooting auxiliary of 0.25, 0.5, and 0.75 times is displayed on the same screen. The magnification ratio is displayed. When the operator selects an arbitrary zoom shooting auxiliary magnification ratio (for example, 0.5 times) from the displayed zoom shooting auxiliary magnification ratio, the selected zoom shooting auxiliary magnification ratio is set (step S61). ).

  FIG. 20 is a flowchart showing an operation when the zoom photographing auxiliary magnification ratio is selected. First, it is determined whether or not assist_magn_rate has been selected to be 0.25 times (step S70). If it is selected to be 0.25 times, the zoom photographing auxiliary magnification ratio is set to 0.25 times (step S71). .

  In step S70, if 0.25 times is not selected, it is determined whether or not assist_magn_rate is selected to be 0.5 times (step S72). If it is selected to be 0.5 times, the zoom-assist magnification ratio is determined. Is set to 0.5 times (step S73).

  If it is determined in step S72 that 0.5 times is not selected, the zoom photographing auxiliary magnification ratio is set to 0.75 (step S74).

  FIG. 21 is a diagram for explaining the magnification setting control in the digital zoom circuit magnification setting during zoom control. The value of position_cnt in FIG. 21A is the same as the value of position_cnt in FIG. 16A, and the value of position_table in FIG. 21B is the same as the value of position_table in FIG. In this embodiment, zoom_assist_magn_table1, zoom_assist_magn_table2, and zoom_assist_magn_table3 are added as shown in FIGS. 21C to 21E instead of zoom_assist_magn_table in FIG.

  According to the present embodiment, the operator can select the zoom photographing auxiliary magnification table according to the selected magnification and determine the magnification of the live view of the auxiliary optical system. As a result, it is possible to obtain a live view display of the zoom photographing assist function suitable for the operator's request.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, each of the above embodiments is only an example of the present invention, and the present invention is not limited only to the configuration of each of the above embodiments. . Needless to say, changes in design and the like within the scope of the present invention are included in the present invention.

DESCRIPTION OF SYMBOLS 10 Imaging device 11 Imaging optical system 12 Auxiliary optical system 13 Image | video I / F
14 Control I / F
15 Image processing chip 16 Display control unit 17 LCD
DESCRIPTION OF SYMBOLS 18 External memory 19 Operation part 22, 23 Zoom lens 24 Zoom lens drive mechanism 25 Zoom lens position detection mechanism 26 Image sensor 31 Fixed focus lens 33 Image sensor 43 Rotary encoder 44 Photo interrupter 51 Digital zoom circuit 52 Image | video I / F
53 Control I / F

JP 2011-045039 A

Claims (6)

An imaging apparatus including a first optical system having a zoom lens and a second optical system different from the first optical system,
The second optical system is set to a digital zoom magnification according to the optical zoom position of the first optical system,
The image pickup apparatus further comprises display means for digitally zooming and displaying image data based on a subject image formed by the second optical system with the digital zoom magnification.


Further comprising setting means for setting the zoom magnification of the second optical system corresponding to the optical zoom position of the first optical system;
When the optical zoom position of the first optical system is changed, the second optical system sets the second optical corresponding to the changed optical zoom position of the first optical system set by the setting means. The imaging apparatus according to claim 1, wherein the imaging apparatus is changed to a zoom magnification of the system.   The image data based on the subject image formed by the first optical system is displayed in live view, and the image data based on the subject image formed by the second optical system is displayed in live view. The imaging apparatus according to claim 1 or 2. A control method of an imaging apparatus including a first optical system having a zoom lens and a second optical system different from the first optical system,
The second optical system is set to a zoom magnification according to the optical zoom position of the first optical system,
A method for controlling an imaging apparatus, comprising: displaying image data based on a subject image formed by the second optical system on a display unit of the imaging apparatus by digital zooming with the digital zoom magnification.



When further comprising a setting means for setting the zoom magnification of the second optical system corresponding to the optical zoom position of the first optical system,
When the optical zoom position of the first optical system is changed, the second optical system is set by the setting means, and the second optical system corresponding to the changed optical zoom position of the first optical system is set. 5. The method according to claim 4, wherein the zoom magnification of the system is changed. The image data based on the subject image formed by the first optical system is displayed in live view, and the image data based on the subject image formed by the second optical system is displayed in live view. The control method of the imaging device according to claim 4 or 5.