JP2011128560A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera enabling panning without blurring even on a low-luminance subject moving at high speed by performing focus control according to the direction of the camera. <P>SOLUTION: The direction of the camera is stored when the acceleration of the camera exceeds a threshold. Then, when a release button is pushed, it is determined whether the direction of the camera is upward or sideways. When the direction of the camera is upward, the focusing lens is driven so that the focus position corresponds to the infinite part. When the direction of the camera is sideways, the focusing lens is driven so that the focus position corresponds to 5 m. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a camera having a function of continuously imaging a subject.

  Along with the increase in the speed of image pickup devices, recent digital cameras can perform one shooting operation in addition to a function (single shooting function or still image shooting function) that performs one shooting according to one shooting operation. Accordingly, there are an increasing number of functions having a function (continuous shooting function or moving image shooting function) for performing imaging a plurality of times. In general, still image shooting can obtain a higher-definition image than moving image shooting, and moving image shooting is suitable for capturing a continuous movement of a subject.

  In Patent Document 1, single shooting and continuous shooting are switched according to the movement of the subject. As a result, continuous shooting is performed for shooting a slow-moving subject, and as a result, only similar images are prevented from being shot.

JP 2000-10162 A

  Here, when shooting a bird flying in the dark (taking pictures such as continuous shooting while moving the camera according to the movement of the subject), the subject bird has low brightness. . In this case, even if the autofocus function is operated, there is a high possibility that it takes time to focus on the bird. Therefore, even if panning is performed, the subject bird may be missed from the shooting range. In addition, even if the image is captured within the shooting range, the out-of-focus photo may be taken.

  By the way, when shooting a flying bird, there is a high possibility that the camera is directed upward. In addition, it is highly possible that the flying bird is located far from the photographer. For this reason, it is considered effective to control the focus so that the camera is forcibly focused at a long distance when the camera is facing upward.

  The present invention has been made in view of the above circumstances, and by performing focus control according to the orientation of the camera, a camera capable of panning without blurring even for a low-luminance subject moving at high speed. The purpose is to provide.

  In order to achieve the above object, a camera according to a first aspect of the present invention captures an image by photographing a subject lens formed by the photographing lens and a photographing lens for forming a subject image. An imaging unit that obtains, a posture detection unit that detects a change in the orientation of the camera accompanying the movement of the camera, and a farther distance than a predetermined distance when the orientation of the camera changes so that the photographing lens faces the sky. And a control unit for controlling the focus position of the photographing lens so as to be the first position which is the first focus position.

  According to the present invention, it is possible to provide a camera capable of panning without blurring a low-luminance subject moving at high speed by performing focus control according to the direction of the camera.

It is a figure which shows the structure of the camera which concerns on each embodiment of this invention. It is a figure for demonstrating an acceleration and attitude | position detection part. It is a flowchart which shows operation | movement of the camera which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating upward of a camera. It is a flowchart which shows operation | movement of the camera which concerns on the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, a first embodiment of the present invention will be described. FIG. 1 is a diagram showing a configuration of a camera according to each embodiment of the present invention.

  A camera 1 shown in FIG. 1 includes a control microcomputer 2, a lens unit 3, an imaging unit 4, a memory unit 5, a display unit 6, an image recording unit 7, an audio processing unit 8, and an operation unit 9. The flash light emitting unit 10 and the acceleration / attitude detection unit 11 are provided.

  The control microcomputer 2 comprehensively controls the operation of each block inside the camera 1 such as the lens unit 3, the imaging unit 4, and the flash light emitting unit 10. Here, the control microcomputer 2 has a plurality of timers 2a that function as time-keeping units for measuring various times. The control microcomputer 2 also performs various types of image processing on the image data obtained via the imaging unit 4 and image compression for recording in the image recording unit 7. Further, the control microcomputer 2 also has a function as a control unit, and controls the focus of the focus lens 31b of the lens unit 3 in accordance with the acceleration of the camera 1 detected by the acceleration / attitude detection unit 11 and the change in the attitude of the camera 1. I do.

  The lens unit 3 includes a photographing lens 31 and a lens control unit 32. The photographing lens 31 is an optical system for condensing the optical image of the subject on the imaging unit 4. The taking lens 31 has a zoom lens 31a and a focus lens 31b. The zoom lens 31a and the focus lens 31b are moved in the optical axis direction by a lens control unit 32 that operates in accordance with an instruction from the control microcomputer 2. The zoom lens 31a is a lens for adjusting the angle of view. By driving the zoom lens 31a of the photographing lens 31 to the wide angle side or the telephoto side by the lens control unit 32, the angle of view at the time of photographing is changed. When the zoom lens 31a is driven to the wide angle side, the angle of view is widened, and a state suitable for photographing in a wide range is obtained. On the other hand, when the zoom lens 31a is driven to the telephoto side, the angle of view becomes narrow, but the state is suitable for photographing a long-distance subject. The focus lens 31b is a lens for adjusting the focus position of the photographing lens 31.

  The imaging unit 4 includes an imaging device 41, an imaging device driver 42, a timing generator (TG) 43, and an analog front end circuit (AFE) 44. The imaging element 41 has an imaging surface in which pixels are arranged in a two-dimensional manner, and the light collected by the photographing lens 31 is received by each pixel and subjected to photoelectric conversion, thereby converting the amount of light into an electrical quantity. Convert. The image sensor driver 42 drives the image sensor 41 in accordance with the synchronization signal from the TG 43. The TG 43 generates a synchronization signal for driving the image sensor 41 according to the timing signal from the control microcomputer 2 and outputs it to the image sensor driver 42. The image sensor 41 operates in synchronization with this synchronization signal. The AFE 44 performs various analog processing such as correlated double sampling (CDS) processing and gain control processing (AGC) on the analog electrical signal (image signal) output from the image sensor 41, and then performs analog processing. The obtained image signal is converted into a digital image signal (hereinafter referred to as image data).

  The memory unit 5 is a storage unit that temporarily stores various data such as image data obtained in the AFE 44 of the imaging unit 4 and image data obtained as a result of image processing in the control microcomputer 2. The memory unit 5 is composed of, for example, a DRAM (Dynamic RAM).

  The display unit 6 is a display unit such as a liquid crystal display provided on the back surface of the camera 1, for example, and displays various images such as an image based on image data image-processed by the control microcomputer 2. The image recording unit 7 is, for example, a memory that can be attached to and detached from the camera 1, and records image data that has been subjected to image processing by the control microcomputer 2.

  The sound processing unit 8 performs processing for emitting various sounds according to the control of the control microcomputer 2.

  The operation unit 9 is an operation member such as a power button, a release button, a zoom button, and various input keys. When one of the operation members of the operation unit 9 is operated by the user, the control microcomputer 2 executes various processes according to the user's operation. Here, the power button is an operation member for instructing to turn on / off the power of the camera 1. When the power button is pressed, the control microcomputer 2 turns the camera 1 on or off. The release button is an operation member for instructing execution of shooting. When the release button is pressed, the control microcomputer 2 executes still image shooting or moving image shooting. The zoom button is an operation member for instructing execution of zooming. When the zoom button is pressed, the control microcomputer 2 sends an instruction to the lens control unit 32 to drive the zoom lens of the photographing lens 31 to the wide angle side or the telephoto side. The input key is, for example, an operation member for setting shooting conditions and the like at the time of shooting on a menu screen displayed on the display unit 6.

  The flash light emitting unit 10 emits light in response to a light emission instruction from the control microcomputer 2 when the subject has a low luminance or a backlight scene. The flash light emitting unit 10 includes an arc tube such as a xenon (Xe) tube and a reflector.

  The acceleration / posture detection unit 11 detects the acceleration generated in the camera 1 and detects the change direction of the posture of the camera 1 from the acceleration. The acceleration / attitude detection unit 11 can be constituted by an angular velocity sensor, for example.

  An example of posture detection will be described with reference to FIG. First, as shown in FIG. 2A, the Z axis is set in the direction along the photographing optical axis of the photographing lens 31 of the camera 1, and the X axis is set along the side of the camera 1 orthogonal to the Z axis. Set the Y axis. The acceleration / attitude detection unit 11 detects the acceleration of the camera 1 in the directions along the X axis, Y axis, and Z axis set as shown in FIG.

For example, when the user holds the camera 1 sideways (in the direction shown in FIG. 2A), gravitational acceleration (1G = 9.8 m / S ² ) is applied in the Y-axis direction. On the other hand, the acceleration in the Z-axis direction is almost zero. Further, when the user holds the camera 1 vertically (the direction in which the camera 1 is rotated by 90 degrees with respect to the horizontal holding), gravitational acceleration (1G) is applied in the X-axis direction. On the other hand, the acceleration in the Z-axis direction is almost zero. Thus, the posture of the camera 1 can be detected from the degree of gravitational acceleration in the X-axis direction, the Y-axis direction, and the Z-axis direction.

  Further, the movement of the camera 1 along the X-axis direction, the Y-axis direction, and the Z-axis direction can be detected from the time change of the acceleration along the X-axis direction, the Y-axis direction, and the Z-axis direction. Furthermore, the amount of movement of the camera 1 can be detected by integrating the acceleration twice over time.

  Further, for example, when a user holding the camera 1 horizontally holds the photographing lens 31 of the camera 1 in the sky direction (direction from the Z axis to the Y axis shown in FIG. 2A), FIG. As shown in FIG. 2C, the acceleration in the Y-axis direction and the Z-axis direction changes abruptly. Thereafter, the acceleration in the Y-axis direction is stabilized in a state where it is slightly reduced from the gravitational acceleration (1G), and the acceleration in the Z-axis direction is stabilized in a state where it is increased to a value close to the gravitational acceleration (1G).

  Further, when the user holding the camera 1 vertically holds the photographing lens 31 of the camera 1 in the sky direction (in this case, the direction from the Z axis toward the X axis), FIG. 2B and FIG. ), The acceleration in the X-axis direction and the Z-axis direction changes abruptly. Thereafter, the acceleration in the X-axis direction is stabilized in a state where it is slightly reduced from the gravitational acceleration, and the acceleration in the Z-axis direction is stabilized in a state where the acceleration in the vicinity of the gravitational acceleration (1G) is increased.

  As described above, it is possible to detect the change in the posture of the camera 1 from the relationship of the time change of the acceleration along the X axis, the Y axis, and the Z axis of the camera 1. For example, the acceleration in the Y-axis direction and the acceleration in the Z-axis direction change abruptly from the state where the camera 1 is held sideways (the Y-axis direction acceleration is 1 G and the Z-axis direction acceleration is 0). When the acceleration in the Z-axis direction ≧ the acceleration in the Y direction in the subsequent stable state, it can be detected that the photographing lens 31 of the camera 1 is directed in the sky direction.

In the example of FIG. 2B, the acceleration in the Y-axis (X-axis) direction when the photographing lens of the camera 1 is directed in the sky direction by 45 ° from the Z-axis to the Y-axis (X-axis). The time change is shown. Similarly, in the example of FIG. 2C, the time change of the acceleration in the Z-axis direction when the photographing lens 31 of the camera 1 is directed in the sky direction by 45 ° from the Z-axis toward the Y-axis (X-axis). Is shown. In such a case, the acceleration in the Y-axis (X-axis) direction and the acceleration in the Z-axis direction are both equal (2 ^−1/2 G). In the focus control operation described later, (2 ^−1/2 G) is used as an acceleration threshold for determining whether or not the posture of the camera 1 has changed.

  Details of the operation of the camera 1 according to the first embodiment will be described below. FIG. 3 is a flowchart specifically illustrating the focus control operation of the camera 1 according to the first embodiment. Although not shown in the operation of FIG. 3, when the power button of the operation unit 9 is turned off, the power of the camera 1 is turned off regardless of the state at that time.

For example, when the power button of the operation unit 9 is turned on, the operation of FIG. 3 is started. When the power button of the operation unit 9 is turned on, the control microcomputer 2 determines that the acceleration (any one of the X-axis direction, the Y-axis direction, and the Z-axis direction) detected by the acceleration / attitude detection unit 11 is It is determined whether or not the threshold (2 ^−1/2 G) has been exceeded (step S1). Although the acceleration threshold is (2 ^−1/2 G) here, the threshold is not necessarily (2 ^−1/2 G).

  In step S1, if the acceleration exceeds the threshold, the control microcomputer 2 determines whether the camera 1 is facing upward or sideways, and stores the determination result in the memory unit 5 (step S2). Here, in the present embodiment, “the state where the camera 1 is facing upward” refers to “a state where the photographing lens 31 of the camera 1 faces the sky”. For example, as shown in FIGS. 4A and 4B, a state in which the photographing lens 31 forms an angle of 45 ° or more with respect to the ground surface is defined as “camera 1 is facing upward”. On the other hand, in the state shown in FIG. 4C or FIG. 4D, the camera 1 is accelerated in the sky direction, but the photographing lens 31 does not face the sky direction. Not. " Further, “the camera 1 is in the sideways direction” means “the direction in which the acceleration direction of the camera 1 is parallel to the ground surface (for example, the direction along the plane formed by the Z axis and the X axis when the camera 1 is horizontally held). It is assumed that the photographing lens 31 of the camera 1 is oriented in a direction parallel to the ground surface. As described above, the orientation of the camera 1 is determined from the relationship between the magnitude of acceleration in the X-axis direction when the acceleration is stabilized, the magnitude of acceleration in the Y-axis direction, and the magnitude of acceleration in the Z-axis direction. can do.

  After storing the orientation of the camera 1 in the memory unit 5 in step S2, the control microcomputer 2 starts a timer Timer1 included in the timer 2a (step S3). Note that the timer Timer1 is a timer for measuring the effective period of the acceleration / attitude detection unit 11, and is a timer for measuring, for example, 3 seconds. Of course, this timekeeping time is an example and can be changed as appropriate.

  After the timer Timer1 is started, the control microcomputer 2 determines whether or not the timer Timer1 has timed out (step S4). If it is determined in step S4 that the timer Timer1 has timed out, the process returns to step S1. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold.

  If it is determined in step S4 that the timer Timer1 has not timed out, the control microcomputer 2 determines whether or not the release button of the operation unit 9 has been pressed to instruct shooting (step S5). If it is determined in step S5 that the release button has not been pressed, the process returns to step S4. In this case, the control microcomputer 2 determines again whether or not the timer Timer1 has timed out.

  That is, even if the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold, if the release button is not pressed for a certain time, the focus lens 31b is driven to the fixed focus position after step S6. Do not do.

  Further, when the release button is pressed in the determination in step S5, the control microcomputer 2 determines whether or not the camera 1 is upward from the information on the orientation of the camera 1 stored in the memory unit 5. (Step S6). In the determination of step S6, when the camera 1 is facing upward, the control microcomputer 2 causes the focus lens 31b to be driven to a position corresponding to infinity as the first position farther than the predetermined distance. An instruction is sent to the lens controller 32 (step S7). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S7, the focus lens 31b is driven to a position corresponding to infinity. However, if the focus position is a predetermined long-distance focus position that can focus on a long-distance subject such as a bird flying over the sky. It is not always necessary to drive the focus lens 31b to infinity.

  Here, the shooting operation after driving the focus lens 31b may be any of a still image shooting operation, a continuous shooting operation, and a moving image shooting operation. The control microcomputer 2 changes these shooting operations to the operation mode of the camera 1, for example. Switch accordingly. In the still image shooting operation, after the image pickup by the image pickup device 41 is performed once, an image obtained by the single operation of the image pickup device 41 is subjected to image processing (still image compression or the like) by the control microcomputer 2, and then after the processing. Are recorded in the image recording unit 7. In the continuous shooting operation, the imaging device 41 performs imaging a plurality of times, and the control microcomputer 2 sequentially performs image processing (still image compression, etc.) on a plurality of images obtained by the operations of the imaging device 41 a plurality of times. Then, the processed image is recorded in the image recording unit 7. In the moving image shooting operation, imaging by the image pickup device 41 is performed a plurality of times, and an image obtained by the operation of the image pickup device 41 a plurality of times is subjected to image processing (moving image compression or the like) by the control microcomputer 2, and then the processed image is processed. Is recorded in the image recording unit 7.

  In step S6, if the camera 1 is not upward, the control microcomputer 2 determines whether the camera 1 is sideways (step S8). In the determination of step S8, when the camera 1 is sideways, the control microcomputer 2 moves the lens so that the focus lens 31b is driven to the 5m position as the second position that is closer than the first position. An instruction is sent to the control unit 32 (step S9). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S9, the focus lens 31b is driven to the 5 m position, but it may be a short distance from the first position.

  In step S8, when the camera 1 is not in the landscape orientation, the control microcomputer 2 drives the focus lens 31b to the 3m position as the third position that is closer than the second position. An instruction is sent to the lens controller 32 (step S10). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S10, the focus lens 31b is driven to the 3m position, but the third position is not limited to the 3m position.

  In step S1, if the acceleration does not exceed the threshold, the control microcomputer 2 determines whether the release button of the operation unit 9 has been pressed to instruct the execution of shooting (step S11). If it is determined in step S11 that the release button has not been pressed, the process returns to step S1. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold. If the release button is pressed in the determination in step S11, the control microcomputer 2 starts automatic focus control (autofocus: AF) (step S12). Note that AF includes a phase difference AF method in which the focus of the focus lens 31b is controlled based on a phase difference between images formed on each of a pair of sensors, and an image contrast obtained via the image sensor 41. There is a hill-climbing AF method that drives the focus lens 31b so as to be maximum. The AF method in the present embodiment is not limited to any method.

After starting the AF, the control microcomputer 2 starts the timer Timer2 included in the timer 2a (step S13). Note that the timer Timer2 is a timer for counting the effective period of AF, for example, a timer for counting 0.1 second. Of course, this timekeeping time is an example and can be changed as appropriate. After the timer Timer2 is started, the control microcomputer 2 determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold (2 ^−1/2 G) (step S14).

  If it is determined in step S14 that the acceleration exceeds the threshold, the control microcomputer 2 determines whether the camera 1 is facing upward or sideways, and stores the determination result in the memory unit 5 (step S15). Thereafter, the control microcomputer 2 performs the processing after step S6.

  In step S14, when the acceleration does not exceed the threshold, the control microcomputer 2 determines whether the in-focus position is detected as a result of AF (step S16). If the in-focus position is not detected in the determination in step S16, the control microcomputer 2 determines whether or not the timer Timer2 has timed out (step S17). If it is determined in step S17 that the timer Timer2 has not timed out, the process returns to step S14. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold.

  If the timer Timer2 times out in the determination in step S17, the control microcomputer 2 performs the process in step S10. That is, the control microcomputer 2 sends an instruction to the lens control unit 32 so that the focus lens 31b is driven to the 3m position as the third position that is closer than the second position. Thereafter, the control microcomputer 2 performs a process of executing a photographing operation.

  Further, when the in-focus position is detected in the determination in step S16, the control microcomputer 2 drives the focus lens 31b to the in-focus position (step S18). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation.

  As described above, in the first embodiment, when the release button is pressed immediately after the camera 1 is directed upward, the focus position becomes a position corresponding to infinity as the first position. The focus lens 31b is driven. By performing such control, it is possible to focus on a desired subject in a short time when the user turns the camera 1 upward to shoot a subject such as a bird moving at high speed in the sky. As a result, the time lag from when the release button is pressed to when the actual shooting is performed can be shortened at the time of panning shooting and the like, and the possibility of taking out-of-focus photos can be reduced.

  In the present embodiment, when the release button is pressed immediately after the camera 1 is turned sideways, the focus lens 31b is driven so that the focus position becomes the 5 m position as the second position. By performing such control, it is possible to focus on a desired subject in a short time when the user turns the camera 1 sideways to shoot a subject that moves at high speed in a lateral direction parallel to the ground surface. is there. As a result, the time lag from when the release button is pressed to when the actual shooting is performed can be shortened at the time of panning shooting and the like, and the possibility of taking out-of-focus photos can be reduced.

  Furthermore, in this embodiment, even after AF is started, if the user turns the camera 1 upward or sideways, the AF is interrupted at that time, and the focus lens 31b is driven to a fixed focus position. Is done. Accordingly, it is possible to shorten the time lag until actual shooting is performed and to reduce the possibility that a blurred photo is shot.

  Here, the process of step S7 in FIG. 3 is a process for enabling photographing of a subject such as a bird moving at high speed in the sky. Since the moving speed of the subject is high, there is a possibility that the subject may move from within the angle of view only by shortening the release time lag. For this reason, in addition to the process of step S7, a process of driving the zoom lens 31a to the wide angle side may be added. As described above, when the zoom lens 31a is driven to the wide angle side, the field angle is widened. For this reason, it is easy to capture a subject moving at high speed within the angle of view. Also, the shooting operation after step S7 in FIG. By taking a moving image, it is possible to capture the continuous movement of the subject.

  Further, the image sensor 41 may be operated during the processing shown in FIG. 3, and the face part in the image obtained by the operation of the image sensor 41 may be detected by the control microcomputer 2. When the face is detected, AF is performed to focus on the face even if acceleration occurs in the camera 1, and the focus lens 31b is driven to a fixed focus position. However, the AF may be switched to focus on the face when the face is detected. That is, it is considered that the user intends to photograph a person while the face portion is detected. Therefore, it is possible to perform focus control more reflecting the user's intention by forcibly performing AF when there is a face in an image obtained via the image sensor 41. When such control is performed, the control microcomputer 2 functions as a face detection unit.

  Further, it is generally known that AF for a low-brightness subject takes more time for AF than AF for a high-brightness subject. Therefore, the subject brightness may be detected before focus control, and the drive control of the focus lens 31b to the fixed focus position may be performed only when the subject brightness is lower than a predetermined level. Note that the subject brightness can be detected based on an image obtained via the image sensor 41, for example. In this case, the control microcomputer 2 functions as a luminance detection unit. Of course, the subject brightness may be detected using a dedicated sensor.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The configuration of the camera 1 in the second embodiment is the same as that shown in FIG. Therefore, the description about a structure is abbreviate | omitted.

  Details of the operation of the camera 1 according to the second embodiment will be described below. FIG. 5 is a flowchart specifically illustrating the focus control operation of the camera 1 according to the second embodiment.

For example, when the power button of the operation unit 9 is turned on, the operation of FIG. 5 is started. When the power button of the operation unit 9 is turned on, the control microcomputer 2 determines that the acceleration (any one of the X-axis direction, the Y-axis direction, and the Z-axis direction) detected by the acceleration / attitude detection unit 11 is It is determined whether or not the threshold (2 ^−1/2 G) has been exceeded (step S21). Here, the acceleration threshold is (2 ^−1/2 G), but the threshold is not necessarily (2 ^−1/2 G).

  When the acceleration exceeds the threshold in the determination in step S21, the control microcomputer 2 determines whether the camera 1 is facing upward or sideways, and stores the determination result in the memory unit 5 (step S22). After storing the orientation of the camera 1 in the memory unit 5 in step S22, the control microcomputer 2 starts a timer Timer1 included in the timer 2a (step S23). Note that the timer Timer1 is a timer for measuring the effective period of the acceleration / attitude detection unit 11, and is a timer for measuring, for example, 3 seconds. Of course, this timekeeping time is an example and can be changed as appropriate.

  After the timer Timer1 is started, the control microcomputer 2 determines whether or not the timer Timer1 has timed out (step S24). If it is determined in step S24 that the timer Timer1 has timed out, the process returns to step S21. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold.

  If it is determined in step S24 that the timer Timer1 has not timed out, the control microcomputer 2 determines whether the release button of the operation unit 9 has been pressed to instruct the execution of shooting (step S25). If it is determined in step S25 that the release button has not been pressed, the process returns to step S24. In this case, the control microcomputer 2 determines again whether or not the timer Timer1 has timed out.

  If the release button is pressed in the determination in step S25, the control microcomputer 2 starts AF (step S26). After the start of AF, the control microcomputer 2 activates the timer Timer3 included in the timer 2a (step S27). Note that the timer Timer3 is a timer for measuring a predetermined time for AF, for example, a timer for measuring 0.1 second. Of course, this timekeeping time is an example and can be changed as appropriate.

  After the timer Timer3 is started, the control microcomputer 2 determines whether or not the in-focus position is detected as a result of AF (step S28). If the in-focus position is not detected in the determination in step S28, the control microcomputer 2 determines whether or not the timer Timer3 has timed out (step S29). If it is determined in step S29 that the timer Timer3 has not timed out, the process returns to step S28. In this case, the control microcomputer 2 determines again whether or not the in-focus position has been detected.

  If the timer Timer3 times out in the determination in step S29, the control microcomputer 2 determines whether the camera 1 is facing upward from the information on the orientation of the camera 1 stored in the memory unit 5 ( Step S30). In the determination in step S30, when the camera 1 is facing upward, the control microcomputer 2 causes the focus lens 31b to be driven to a position corresponding to infinity as the first position farther than the predetermined distance. An instruction is sent to the lens controller 32 (step S31). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S31, the focus lens 31b is driven to a position corresponding to infinity. However, if the focus position is a predetermined long-distance focus position capable of focusing on a long-distance subject such as a bird flying over the sky. It is not always necessary to drive the focus lens 31b to a position corresponding to infinity.

  In step S30, if the camera 1 is not upward, the control microcomputer 2 determines whether the camera 1 is sideways (step S32). In the determination of step S32, when the camera 1 is sideways, the control microcomputer 2 moves the lens so that the focus lens 31b is driven to the 5m position as the second position that is closer than the first position. An instruction is sent to the control unit 32 (step S33). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S33, the focus lens 31b is driven to the 5m position, but it may be a short distance from the first position.

  Further, in the determination of step S32, when the camera 1 is not in the horizontal direction, the control microcomputer 2 causes the focus lens 31b to be driven to the 3m position as the third position that is closer than the second position. An instruction is sent to the lens controller 32 (step S34). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation. In step S34, the focus lens 31b is driven to the 3m position, but the third position is not limited to the 3m position.

  In step S21, if the acceleration does not exceed the threshold, the control microcomputer 2 determines whether the release button of the operation unit 9 has been pressed and execution of shooting has been instructed (step S35). If it is determined in step S35 that the release button has not been pressed, the process returns to step S21. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold. If the release button is pressed in the determination in step S35, the control microcomputer 2 starts AF (step S36).

After starting the AF, the control microcomputer 2 activates the timer Timer2 included in the timer 2a (step S37). Note that the timer Timer2 is a timer for counting the effective period of AF, for example, a timer for counting 0.1 second. Of course, this timekeeping time is an example and can be changed as appropriate. After the timer Timer2 is started, the control microcomputer 2 determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds a threshold (2 ^−1/2 G) (step S38).

  If the acceleration exceeds the threshold in the determination in step S38, the control microcomputer 2 determines whether the camera 1 is facing upward or sideways, and stores the determination result in the memory unit 5 (step S39). Thereafter, the control microcomputer 2 performs the processing after step S30.

  In step S38, if the acceleration does not exceed the threshold, the control microcomputer 2 determines whether the in-focus position is detected as a result of AF (step S40). If the in-focus position is not detected in the determination in step S40, the control microcomputer 2 determines whether or not the timer Timer2 has timed out (step S41). If it is determined in step S41 that the timer Timer2 has not timed out, the process returns to step S38. In this case, the control microcomputer 2 again determines whether or not the acceleration detected by the acceleration / attitude detection unit 11 exceeds the threshold.

  If the timer Timer2 times out in the determination in step S41, the control microcomputer 2 performs the process in step S34. That is, the control microcomputer 2 sends an instruction to the lens control unit 32 so that the focus lens 31b is driven to the 3m position as the third position that is closer than the second position. Thereafter, the control microcomputer 2 performs a process of executing a photographing operation.

  Further, when the in-focus position is detected in the determination in step S40, the control microcomputer 2 drives the focus lens 31b to the in-focus position (step S42). Thereafter, the control microcomputer 2 performs a process of executing a photographing operation.

  As described above, in the second embodiment, AF is performed first even when the release button is pressed immediately after the camera 1 is directed upward or immediately after it is turned sideways. The focus lens 31b is driven to a fixed position only when the focus is not achieved within a predetermined time by AF. By performing such control, as in the first embodiment, it is possible to shorten the time lag until actual shooting is performed and to reduce the possibility of taking out-of-focus photos. In the second embodiment, the time required for focus control tends to be longer than that in the first embodiment, but it is possible to perform focus control with higher accuracy than in the first embodiment.

  Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications and applications are naturally possible within the scope of the gist of the present invention.

  Further, the above-described embodiments include various stages of the invention, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some configuration requirements are deleted from all the configuration requirements shown in the embodiment, the above-described problem can be solved, and this configuration requirement is deleted when the above-described effects can be obtained. The configuration can also be extracted as an invention.

  DESCRIPTION OF SYMBOLS 1 ... Camera, 2 ... Control microcomputer, 2a ... Timer, 3 ... Lens part, 4 ... Imaging part, 5 ... Memory part, 6 ... Display part, 7 ... Image recording part, 8 ... Sound processing part, 9 ... Operation part DESCRIPTION OF SYMBOLS 10 ... Flash light emission part, 11 ... Acceleration and attitude | position detection part, 31 ... Shooting lens, 31a ... Zoom lens, 31b ... Focus lens, 32 ... Lens control part, 41 ... Image sensor, 42 ... Image sensor driver, 43 ... Timing Generator (TG), 44 ... Analog front-end circuit (AFE)

Claims (9)

A photographic lens for forming an image of the subject;
An imaging unit that captures an image of a subject formed by the photographing lens to obtain an image;
An attitude detection unit that detects a change in the orientation of the camera accompanying the movement of the camera;
A control unit that controls the focus position of the photographic lens so that the first position, which is a focus position farther than a predetermined distance when the orientation of the camera is changed so that the photographic lens faces the sky, ,
A camera comprising:   The camera according to claim 1, wherein the first position is a focus position corresponding to infinity.   The control unit becomes a second position that is a focus position closer to the first position when the orientation of the camera is changed so that the photographing lens moves in a direction parallel to the ground surface. The camera according to claim 1 or 2, wherein the focus position of the photographing lens is controlled as described above.   The controller does not change the orientation of the camera so that the photographing lens faces the sky, and changes the orientation of the camera so that the photographing lens moves in a direction parallel to the ground surface. 4. The focus position of the photographic lens is controlled to be a third position, which is a focus position closer to the near side than the second position when there is no such position. Camera described in. The photographing lens includes a zoom lens for adjusting the angle of view of an image obtained in the imaging unit,
5. The control unit according to claim 1, wherein the control unit further drives the zoom lens to a wide-angle side when the orientation of the camera changes so that the photographing lens faces the sky. The camera according to item 1. Further comprising an acceleration detection unit for detecting acceleration accompanying the movement of the camera,
The control unit automatically controls the focus position of the photographing lens regardless of the orientation of the camera when the acceleration is less than a predetermined value, and the orientation of the camera when the acceleration exceeds the predetermined value. 6. The camera according to claim 1, wherein the focus position of the photographic lens is controlled in accordance with the camera. An acceleration detection unit for detecting acceleration accompanying the movement of the camera;
A timekeeping section for measuring a predetermined time;
Further comprising
The control unit automatically controls the focus position of the photographing lens regardless of the orientation of the camera when the acceleration is less than a predetermined value or when the acceleration is equal to or greater than the predetermined value and within the predetermined time, 6. The focus position of the photographing lens is controlled according to the direction of the camera when the acceleration is equal to or greater than the predetermined value and exceeds the predetermined time. camera. A face detection unit for detecting a face in the image obtained by the imaging unit;
When the face is detected in the image obtained by the imaging unit, the control unit sets the focus position of the photographing lens so that the face is focused regardless of the orientation of the camera and the acceleration. The camera according to claim 6 or 7, wherein the camera is automatically controlled. A luminance detection unit for detecting the luminance of the subject;
The control unit is configured to control a focus position of the photographing lens according to a direction of the camera regardless of acceleration of the camera when the luminance of the subject is lower than a predetermined level. Item 8. The camera according to Item 6 or 7.

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