JP2009080244A - Imaging apparatus and method for correcting irradiation area in imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus, wherein a subject is irradiated with appropriate light even when blurring is optically corrected. <P>SOLUTION: The imaging apparatus 1 is equipped with a light emitting means 55 continuously emitting light to the subject, and generates an image signal by forming an image of the subject on an imaging device through an imaging optical system 10, wherein an amount of blurring is detected, and the blurring is optically corrected by moving at least part of the imaging optical system 10 and also the irradiation area of the light emitting means 55 is corrected based on the detected amount of the blurring. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging apparatus including a light emitting unit, and more particularly to an irradiation region correction method for changing an irradiation region of a light emitting unit.

Conventionally, imaging devices using a Xe (xenon) tube, an LED (light emitting diode) or the like as a light source of a flash are widely used. For example, such an imaging apparatus includes a plurality of light sources, and a plurality of lenses that condense the light emitted from these light sources, respectively. (Patent Document 1), a subject distance is detected for each region in the image, and the amount of light is changed based on the detection result (Patent Document 2). Then, by changing the number of LEDs to be lit, a necessary irradiation angle is obtained (Patent Document 3), a plurality of flash light sources are provided, a face is detected from an image, and flash is performed based on the detection result There is one that changes the irradiation range of flash light by selecting a light source to emit light (Patent Document 4).
JP 2004-196864 A JP 2005-017812 A JP 2005-338280 A JP 2006-3400000

  On the other hand, a flash using an Xe tube as a light source instantaneously emits a large amount of light, whereas a flash using an LED as a light source has a small amount of light, and requires a subject by continuously emitting light during the exposure time. To compensate for the amount of light to be emitted, the exposure time becomes longer. If the exposure time is increased, camera shake is likely to occur, so that camera shake correction is required. When the optical axis of the shooting optical system is corrected by camera shake correction, the shooting angle of view changes. Moreover, there is a possibility that the irradiation area of the LED flash is changed by changing only the shooting angle of view with the imaging apparatus main body as it is, so that appropriate irradiation cannot be performed with respect to the shooting angle of view.

  However, none of the above conventional imaging devices irradiate the LED in response to camera shake correction.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an imaging apparatus capable of irradiating a subject with appropriate light even when optical image stabilization is performed in the imaging apparatus. It is the purpose.

An image pickup apparatus according to the present invention includes an image pickup unit that forms an image of a subject on an image pickup device via a shooting optical system to generate an image signal;
Camera shake detection means for detecting the amount of camera shake;
Optical camera shake correction means for correcting camera shake by moving at least a part of the photographing optical system based on the camera shake amount detected by the camera shake detection means;
A light emitting means for continuously emitting light to the subject;
And an irradiation region correction unit that corrects the irradiation region of the light emitting unit based on the amount of camera shake detected by the camera shake detection unit.

  Here, the “irradiation area” includes the irradiation position, the irradiation shape, and the size of the irradiation area. Examples of the “light emitting means for continuously emitting light” include those using LEDs (light emitting diodes), organic EL (organic electroluminescence), light bulbs, etc., and can emit light for a long time. Shall. Note that “continuously” may include a change in the amount of light due to a voltage drop or the like.

In the imaging device of the present invention, the light emitting means has a plurality of light emitting elements,
The irradiation area correction unit may change the irradiation area by controlling light emission amounts of the plurality of light emitting elements.

In the imaging apparatus according to the aspect of the invention, the light-emitting unit includes a plurality of light-emitting elements, and a split irradiation mode in which the subject is irradiated in a divided manner by controlling light emission amounts of the plurality of light-emitting elements, respectively, and the subject And an overall irradiation mode for irradiating the entire area,
The irradiation area correction unit may change the irradiation area only when the light emitting unit is in the divided irradiation mode.

  In the imaging apparatus of the present invention, the irradiation area correction unit may mechanically change the irradiation area.

  In the imaging apparatus according to the aspect of the invention, the irradiation region correction unit may change the size of the irradiation region based on the light emission time of the light emitting unit.

In the imaging device of the present invention, the imaging device further includes an object detection means for detecting a predetermined object from the image signal,
The irradiation area correction means changes the light emission amount and / or the irradiation area of the light on the object detected by the object detection means in the subject based on the light emission time of the light emission means. There may be.

In the image pickup apparatus of the present invention, the optical camera shake correction unit and the irradiation area correction unit include a switching unit that can be switched on / off,
It is preferable that the irradiation area correction unit is turned on only when the optical camera shake correction unit is on.

In the imaging apparatus of the present invention, the imaging optical system includes a zoom lens,
The irradiation area correction unit may be driven only when a zoom magnification of the zoom lens is larger than a predetermined value.

  In the imaging apparatus of the present invention, the irradiation area correction unit may be driven only when an F value of a diaphragm included in the photographing optical system is larger than a predetermined value.

An irradiation region correction method according to the present invention includes a light emitting unit that continuously emits light to a subject, and forms an image signal by forming an image of the subject on an image sensor via a photographing optical system. In the device
Detect the amount of camera shake,
Based on the detected amount of camera shake, at least a part of the imaging optical system is moved to optically correct camera shake and to correct the irradiation area of the light emitting means.

  According to the imaging device and the irradiation region correction method in the imaging device of the present invention, the amount of camera shake is detected, and the irradiation region of the light emitting unit that continuously emits light to the subject is detected based on the detected amount of camera shake. Since correction is performed, when the camera shake is optically corrected by moving at least a part of the imaging optical system based on the amount of camera shake, the optical angle of the photographic optical system is tilted by the camera shake correction and the angle of view changes. Even so, the irradiation area of the light emitting means can be corrected following the change in the angle of view. Thereby, even if optical image stabilization is performed in the imaging apparatus, it is possible to irradiate the subject with appropriate light.

  Hereinafter, an embodiment of an imaging apparatus according to the present invention will be described in detail with reference to the drawings. In the following embodiments, a digital camera will be described as an example of the imaging apparatus in the present invention. However, the scope of the present invention is not limited to this, and for example, a light emitting unit that continuously emits light such as an LED. Can be applied to other electronic devices having an electronic imaging function such as a mobile phone with a camera and a PDA with a camera. FIG. 1 is a block diagram showing the functional configuration of the digital camera 1.

  As shown in FIG. 1, the digital camera 1 has, as an operation system of the digital camera 1, an operation mode switch for switching each operation mode, a menu / OK button, a zoom / up / down arrow lever, a left / right arrow button, a release button for instructing shooting, An operation unit 52 such as a power switch (not shown) is connected to the CPU 50 via an operation system control unit 51 which is an interface for transmitting to the CPU 50. The release button can be operated in two steps, half-pressed and fully pressed, and normally performs AE processing and AF processing when half-pressed, and instructs the start of shooting when fully pressed.

  The LED flash control unit 55 controls the light emission operation of the LED 55 by driving the LED (light emitting diode) 55 by the LED drive circuit 54. When the release button is pressed, the LED flash control unit 55 causes the LED 55 to emit light necessary for photographing. To the subject. A plurality (three in this embodiment) of LEDs 55-1 to 55-3 can be connected to the LED drive circuit 54. The LED flash control unit 55, the LED drive circuit 54, and the plurality of LEDs 55 constitute an LED flash (first light emitting means).

  The Xe tube flash controller 56 controls the light emission operation of the Xe tube 58 by causing the Xe (xenon) tube drive circuit 57 to drive the Xe (xenon) tube 58, and when the release button is pressed, The tube 58 is irradiated with light necessary for photographing on the subject. The Xe tube flash controller 56, the Xe tube drive circuit 57, and the Xe tube 58 constitute an Xe tube flash (second light emitting means).

  In addition, as a configuration of the photographing optical system 10 for forming a subject image on a predetermined imaging surface (CCD or the like inside the camera body), a focus lens 10a, a zoom lens 10b, an aperture 11, a shutter 12, and the like Is provided. Each lens is step-driven by a focus lens driving unit 21 and a zoom lens driving unit 22 including a motor and a motor driver, and is movable in the optical axis direction. The focus lens driving unit 21 step-drives the focus lens 10 a based on the focus driving amount data output from the AF processing unit 38. The zoom lens driving unit 22 controls step driving of the zoom lens 10 b based on the operation amount data of the zoom / up / down arrow lever 13.

  The diaphragm 11 is driven by a diaphragm driving unit 23 including a motor and a motor driver. The aperture drive unit 23 adjusts the aperture diameter of the aperture 11 based on aperture value data output from an AE processing unit 39 described later.

  The shutter 12 is a mechanical shutter and is driven by a shutter driving unit 24 including a motor and a motor driver. The shutter drive unit 24 controls the opening and closing of the shutter 12 according to a signal generated by pressing the release button and the shutter speed data output from the AE processing unit 39. At this time, the exposure starts when the shutter 12 is opened, and the exposure ends when the shutter 12 is closed.

  Behind the photographing optical system 10 is a CCD 13 that is a photographing element. The CCD 13 has a photocathode in which a large number of light receiving elements are arranged in a matrix, and subject light that has passed through the imaging optical system 10 is imaged on the photocathode and subjected to photoelectric conversion. In front of the photocathode, a microlens array (not shown) for condensing light on each pixel and a color filter array (not shown) in which RGB filters are regularly arranged are arranged. Yes.

  The CCD 13 reads out the charges accumulated for each pixel line by line in synchronization with the vertical transfer clock signal and horizontal transfer clock signal supplied from the CCD control unit 25 and outputs them as a serial analog image signal. The charge accumulation time in each pixel, that is, the exposure time is determined by an electronic shutter drive signal given from the CCD control unit 25. An imaging unit (imaging means) 100 is configured including the photographing optical system 10, the CCD 13, and the CCD control unit 25.

  The analog image signal output from the CCD 13 is input to the analog signal processing unit 30. The analog signal processing unit 30 includes a correlated double sampling circuit (CDS) that removes noise from the analog image signal, an auto gain controller (AGC) that adjusts the gain of the analog image signal, and converts the analog image signal into digital image data. It comprises an A / D converter (ADC) for conversion. The digital image data converted into the digital signal is CCD-RAW data having RGB density values for each pixel.

  The timing generator 31 generates a timing signal. This timing signal is input to the shutter drive unit 24, the CCD control unit 25, and the analog signal processing unit 30 to operate the release button, open / close the shutter 12, and the CCD 13 And the analog signal processing unit 30 are synchronized.

  The image input controller 32 writes the CCD-RAW data input from the analog signal processing unit 30 in the frame memory 33. The frame memory 33 is a working memory used when various digital image processing (signal processing) described later is performed on the image data. For example, an SDRAM that transfers data in synchronization with a bus clock signal having a fixed period. (Synchronous Dynamic Random Access Memory) is used.

  The display control unit 34 is for displaying the image data stored in the frame memory 33 on the liquid crystal monitor 35 as a through image. For example, the display control unit 34 combines one luminance (Y) signal and one color (C) signal. The signal is converted into a composite signal and output to the liquid crystal monitor 35. The through image is acquired at a predetermined time interval and displayed on the liquid crystal monitor 35 while the shooting mode is selected. Further, the display control unit 34 causes the liquid crystal monitor to display an image based on the image data stored in the external recording medium 37 and read out by the media control unit 36.

  The object detection unit (object detection means) 46 detects a predetermined object such as a human face from image data stored in the frame memory 33, that is, a through image. Specifically, an area having the characteristics of the object (face) included in the object (face) (for example, having skin color, eyes, or face shape) is detected as the object (face) area. For example, when the object is a face, the face may be detected by matching the image data of both eyes, the face may be detected from the positional relationship between the eyes and the mouth, etc. The face region may be specified by detection, detection of color information corresponding to the skin of the face, or the like, or a known technique can be used.

  The AF processing unit 38 detects a focus position based on the image data, determines a focus setting value (focus drive amount), and outputs focus drive amount data (AF processing). At this time, the focus setting value may be determined based on the detection result of the object detection unit 46. As a focus position detection method, for example, a passive method is used in which a focus position is detected by using a feature that an in-focus evaluation value (contrast value) of an image increases in a focused state.

  The AE processing unit (exposure calculating means) 39 measures subject luminance (photometric value) based on the image data, determines exposure setting values such as an aperture value, shutter speed, and exposure time based on the measured subject luminance, Aperture value data and shutter speed data are output (AE processing). At this time, the exposure setting value may be determined based on the detection result of the object detection unit 46.

  The AWB processing unit 40 automatically adjusts the white balance at the time of imaging (AWB processing). Note that the AWB processing unit 40 can adjust the white balance before or after imaging.

  The camera shake detection unit 44 detects vibration of the main body of the digital camera 1 caused by a user's camera shake, and can be configured by a gyro sensor, an acceleration sensor, or the like. Then, the detected vibration is converted into an electric signal and input to the CPU 50 as a camera shake amount. The input camera shake amount is stored in the internal memory 43. The camera shake detection unit 44 of the present embodiment detects the amount of camera shake using the above-described sensor. However, the present invention is not limited to this. For example, the first image captured by the imaging unit at the time of actual shooting and stored in the frame memory 33 is used. It is also possible to use electronic camera shake detection means for detecting the amount of camera shake by comparing the image data and image data captured and stored thereafter and calculating the difference.

  A camera shake correction unit (optical camera shake correction unit, camera shake correction unit) 45 is a correction lens (not shown) provided in the photographing optical system 10 based on the amount of camera shake detected by the camera shake detection unit 44. Is moved in a direction to cancel camera shake, thereby correcting the optical axis of the photographing optical system 10. This suppresses the movement of light reaching the CCD 13 to optically reduce camera shake.

  In the present embodiment, the camera shake is corrected as described above. For example, the CCD 13 is moved in the direction of canceling the camera shake based on the amount of the camera shake, so that the CCD 13 causes the optical axis of the photographing optical system 10 to move. So-called image sensor shift type camera shake correction may be performed. Further, the image-capturing area is narrowed to a certain size, the image data stored in the frame memory 33 is read, the first captured image is compared with the image captured after that, the difference amount is calculated, and the image-capable area is calculated. So-called electronic camera shake correction may be performed.

  Further, it is assumed that the camera shake correction unit 45 can be switched on / off when the user operates the operation unit 52, for example. For example, when the camera shake mode is set to ON by the user operating the operation unit 52, the camera shake correction unit 45 performs the above-described correction.

  The image processing unit 41 performs image quality correction processing such as gamma correction processing, contour enhancement (sharpness) processing, contrast processing, noise reduction processing, and the like on the image data of the main image, and converts the CCD-RAW data to a luminance signal Y. YC processing for converting the data into YC data composed of Cb data that is a blue color difference signal and Cr data that is a red color difference signal is performed.

  The main image is taken in from the CCD 13 when a photographing instruction is given by the photographer, for example, when the release button is fully pressed, and stored in the frame memory 33 via the analog signal processing unit 30 and the image input controller 32. This is an image based on image data, and acquiring this main image is called main shooting.

  Although the upper limit of the number of pixels of the main image is determined by the number of pixels of the CCD 13, for example, the number of recorded pixels can be changed by image quality settings (settings such as fine and normal) that can be set by the photographer. On the other hand, the number of pixels of the through image or the like may be smaller than that of the main image.

  The compression / decompression processing unit 42 performs compression processing in a compression format such as JPEG on the image data of the main image that has been subjected to processing such as image quality correction by the image processing unit 41 to generate an image file. This image file is a tag that stores incidental information such as whether it is an image taken in the LED 55 emission mode, Xe tube emission mode, camera shake mode, or irradiation area correction mode based on the Exif format, etc. Is added.

  The compression / decompression processing unit 42 reads a compressed image file from the external recording medium 37 and performs decompression processing in the reproduction mode. The decompressed image data is output to the display control unit 34, and the display control unit 34 displays an image based on the image data on the liquid crystal monitor 35.

  The media control unit 36 reads an image file or the like stored in the external recording medium 37 or writes an image file. The internal memory 43 stores various constants set in the digital camera 1, programs executed by the CPU 50, and the like. The CPU 50 controls each part of the main body of the digital camera 1 in accordance with the operation of the operation unit 52 and signals from each functional block.

  The data bus 47 is connected to the image input controller 32, various processing units 38 to 42, the frame memory 33, various control units 34 and 36, the internal memory 43, the camera shake detection unit 44, the object detection unit 46, and the CPU 50. Various signals and data are transmitted and received through the data bus 47. In this way, the digital camera 1 is configured.

  Next, processing performed at the time of shooting in the digital camera 1 configured as described above will be described with reference to the drawings. FIG. 2 is a graph showing the relationship between the light emission amount and light emission time of LED and Xe and the exposure time, and FIG. 3 is a flowchart of a series of photographing processes by the digital camera 1. In the graph of FIG. 2, the horizontal axis represents time, and the vertical axis represents the amount of light emission.

  Since the Xe tube flash instantaneously emits light with a large light emission amount P2, as shown in FIG. 2, the amount of light required by the subject can be obtained in a relatively short time t1 during the exposure time. For this reason, since the exposure time can be shortened, that is, the shutter speed can be increased, the movement of the main body of the digital camera 1 caused by the shake of the user's hand hardly affects the main image.

  On the other hand, since the LED flash emits light continuously and stably with a light quantity P1 smaller than P2, it is necessary to emit light for t2 for a long time during the exposure time in order to obtain the light quantity required by the subject. For this reason, the exposure time becomes long, and when the exposure time becomes long, the main image is blurred due to the movement of the main body of the digital camera 1 caused by the shaking of the user's hand. This blurring of the main image is referred to as so-called camera shake.

  Therefore, in the present invention, camera shake correction is performed only when shooting is performed by the imaging unit 100 during light emission by the LED flash whose exposure time is long.

  In photographing by the digital camera 1, as shown in FIG. 3, the CPU 50 first determines the light emission mode (step S1). As the light emission mode, for example, an LED light emission mode, an Xe tube light emission mode, and an off mode can be selected, and the user can arbitrarily select the light emission mode by operating the operation unit 52.

  When the CPU 50 determines that the light emission mode is the Xe tube light emission mode (step S1; Xe tube light emission), the CPU 50 sets 1 to the flag (step S2) and determines that the light emission mode is the LED light emission mode (step S1; LED light emission). ), The camera shake mode is automatically turned on, the camera shake correction unit 45 is turned on (step S3), and the flag is set to 0 (step S4).

  Next, the CPU 50 determines whether or not the release button is half-pressed (step S5). If the release button is not half-pressed (step S5; NO), the process of step S5 is repeated until the release button is half-pressed.

  On the other hand, when the release button is half-pressed (step S5; YES), the AWB processing unit 40 performs AWB processing (step S6), and the AE processing unit 39 and the AF processing unit 38 perform AE processing and AF processing, respectively. It carries out in order (step S7). At this time, the AE processing unit 39 determines the above-described exposure setting value in consideration of whether the flag is 1 or 0, that is, whether the light emission at the time of photographing is the light emission by the Xe tube or the LED.

  Then, the CPU 50 determines whether or not the release button has been fully pressed (step S8). If the release button has not been fully pressed (step S8; NO), the process of step S8 is repeated until the release button is fully pressed. If the half-press is released at this time, the CPU 75 proceeds to step S5.

  On the other hand, when the release button is fully pressed (step S8; YES), the CPU 50 determines whether or not the flag is 1 (step S9), and when the flag is 1 (step S9; YES). Since the light emission mode is the Xe tube light emission mode, the shutter drive unit 24 opens the shutter 12 to start exposure (step S10), and the Xe tube flash control unit 56 causes the Xe tube 58 to emit light (step S11).

  When the exposure time determined by the AE process in step S7 has elapsed, the shutter drive unit 24 closes the shutter 12 to end the exposure (step S12), and the shooting is ended.

  On the other hand, if the flag is not 1 in step S9, that is, 0 (step S9; NO), the LED flash control unit 53 causes the LED 55 to emit light (step S13), and the shutter drive unit 24 opens and closes the shutter 12. Thus, exposure is performed (step S14). At this time, since the camera shake correction unit 45 is set to ON in step S3, the camera shake correction unit 45 performs camera shake correction during exposure based on the camera shake amount detected by the camera shake detection unit 44. When the exposure is finished, the LED flash control unit 53 stops the light emission of the LED 55 (step S15), and the photographing is finished.

  As described above, the camera shake mode is turned on and the camera shake correction unit 45 performs camera shake correction only when shooting is performed during light emission by the LED flash. Therefore, camera shake correction is automatically performed only when necessary. Therefore, it is possible to reduce the power consumption by saving the user's operation and reducing the power required for camera shake correction.

  Note that the camera shake mode must be turned on even when the Xe tube flash is used for shooting modes such as when the front is flashed in a dark environment, such as slow sync, or when the background is brightly exposed by long exposure. Can do. Even in the case of light emission by the LED flash, the camera shake mode, that is, the camera shake correction unit 45 may be switched on / off according to the light emission time, that is, the exposure time calculated by the AE processing unit 39. In this case, for example, processing is performed between step S1 and step S3 to switch off when the exposure time is 1/100 second or less, and to turn on when the exposure time is 1/100 second or more. In this way, wasteful power consumption can be reduced.

  Next, a digital camera 1-2 according to another embodiment will be described in detail with reference to the drawings. FIG. 4 is a block diagram showing a functional configuration of the digital camera 1-2. Since the digital camera 1-2 of the present embodiment is substantially the same as the functional configuration of the digital camera 1 in FIG. 1, the same parts are denoted by the same reference numerals and the description thereof is omitted, and only different parts will be described.

  The digital camera 1-2 according to the present embodiment includes an irradiation area correction unit 60 as shown in FIG. The irradiation area correction unit 60 corrects the irradiation area of the LED flash based on the amount of camera shake detected by the camera shake detection means. The irradiation region correction unit 60 may include a switching unit that can be switched on / off. For example, when the user operates the operation unit 52, ON / OFF can be set.

  Note that the camera shake correction unit 45 in the digital camera 1-2 enables only the above-described optical camera shake correction. The digital camera 1-2 does not include the Xe tube flash, but may include it.

  Here, FIG. 5 shows an example of the optical axis a1 and the photographing field angle a2 of the photographing optical system 10, and the optical axis b1 and the irradiation region b2 of the LED 55, respectively. In FIG. 5, (a) is an example during normal shooting, (b) is during camera shake correction, and (c) is an example during camera shake correction and irradiation area correction.

  As shown in FIG. 5A, during normal shooting by the digital camera 1, that is, shooting without camera shake correction by the camera shake correction unit 45, an irradiation region b2 that satisfies a shooting field angle a2 arbitrarily set by the user. Illuminate the subject with light.

  However, as shown in FIG. 5B, at the time of photographing during optical camera shake correction by the digital camera 1, for example, when the digital camera 1 body shakes downward (downward on the paper) by the user's hand, the photographing optical system 10 By moving the optical axis a1 upward so that it does not face downward, the photographing field angle a2 is corrected so as not to change. At this time, since the main body of the digital camera 1 remains in a state of being shaken downward, the optical axis b1 ′ of the LED 55 provided on the main body of the digital camera 1 faces downward according to the direction of the main body of the digital camera 1, and thus the irradiation region b2 ′. Will also shift to the bottom of the subject.

  Therefore, in the digital camera 1-2 of this embodiment, the irradiation area correction unit 60 corrects the irradiation area of the LED 55, that is, the LED flash. Here, FIG. 6 shows a flowchart of a series of photographing processing by the digital camera 1-2.

  In the digital camera 1-2, as shown in FIG. 6, first, the CPU 50 determines whether or not the camera shake correction unit 45 is set to ON (step S20). When the camera shake correction unit 45 is set to ON (step S20; YES), the camera shake detection unit 44 detects camera shake (step S21), and the camera shake correction unit is based on the detected camera shake amount. 45 corrects camera shake (step S22). The processes in steps S21 and S22 are repeated until the exposure is completed.

  Next, the CPU 50 determines whether or not the release button is half-pressed. (Step S23) If the camera shake correction unit 45 is not set to ON in step S20, that is, if it is set to OFF (step S20; NO), the CPU 50 proceeds to step S23.

  If the release button is not half-pressed (step S23; NO), the process of step S23 is repeated until the release button is half-pressed. If the release button is half-pressed (step S23; YES), AWB The processing unit 40 performs AWB processing (step S24), and the AE processing unit 39 and the AF processing unit 38 sequentially perform AE processing and AF processing, respectively (step S25).

  Next, the CPU 50 determines whether or not the release button has been fully pressed (step S26). If the release button has not been fully pressed (step S26; NO), the process of step S26 is repeated until the release button is fully pressed. If the half-press is released at this time, the CPU 75 shifts the processing to step S23.

  On the other hand, when the release button is fully pressed (step S26; YES), it is determined whether or not the irradiation area correction unit 60 is set to on (step S27), and when it is set to on (step S27). YES), the LED flash control unit 53 irradiates the LED 55 toward the subject, and the irradiation region correction unit 60 corrects the irradiation region of the LED flash based on the amount of camera shake. At this time, the irradiation region correction unit 60 initializes the positional relationship between the optical axis a1 of the photographing optical system 10 and the optical axis b1 of the LED 55 to be the positional relationship before the camera shake correction is driven, and Start correction.

  Here, a method of correcting the irradiation region by the irradiation region correction unit 60 will be described. 7 and 8. FIG. 9 is an example of the structure of an LED flash that mechanically changes the irradiation area. FIG. 7 (a) is an overall perspective view, FIG. 7 (b) is a top view of the main part, and FIG. FIG. 8 and 9 are side views, respectively.

  As shown in FIG. 7A, for example, a plurality of LEDs 55-1 to 55-6 are adhered to the mounting plate 55a so that the respective optical axes b1 are directed in substantially the same direction. The attachment plate 55a is attached to a single support plate 55c via an elastic member 55b composed of, for example, a spring or a damper. Then, by driving the mounting plate 55a, for example, by the control member 55d, as shown in FIG. 7 (b), the mounting plate 55a is viewed from above in FIG. As shown in FIG. 7 (c), the upper and lower elastic members 55a are changed as seen from the front side of the mounting plate 55a as shown in FIG. 7 (c). Thus, the optical axis b1 is varied in the vertical direction as the optical axis b1 ′. In this way, the irradiation area is corrected by changing the position of the optical axis b1 of the LED 55.

  In addition, as shown in FIG. 8, the LED flash has a reflection control member 55f that protrudes from both the upper and lower sides of the LED 55 and reflects the light from the support plate 55c to which the LED 55 is attached, and has a projection on the reflection member 55e side. Is moved in the front-rear direction of the optical axis b1 of the LED 55, the reflection control member 55f changes the front end side of the reflection member 55e inward or outward. In this way, the irradiation area of the LED 55 is changed in the vertical direction by changing the reflecting member 55e. The left and right sides of the LED 55 are configured in the same manner, thereby changing the irradiation area of the LED 55 in the left-right direction. In this way, the irradiation area may be corrected.

  In addition, the LED flash does not include the reflection control member 55f of the above embodiment, but a lens 55g is disposed in front of the LED 55, and a lens driving member 55h that moves the lens 55g back and forth in the direction of the optical axis b1 of the LED 55 is disposed. By providing, the irradiation area may be corrected in the same manner as described above.

  As described above, the irradiation area of the LED flash can be mechanically changed.

  In the embodiment described above, the irradiation area correction unit 60 mechanically changes the irradiation area of the LED flash, but the present invention is not limited to this. FIG. 10 shows an example of the relationship between the irradiation area 7 and the imaging range P when the LED flash has a plurality of LEDs (light emitting elements) 55.

  When a plurality of LEDs 55 are used, the irradiation region 7 is set so as to irradiate the entire photographing range P as shown in FIG. 10A during normal photographing, that is, when camera shake correction is not performed. However, when the optical axis of the photographic optical system 10 is shifted to the lower left, for example, by the camera shake correction by the camera shake correction unit 45, the camera moves from the shooting range P to the shooting range P 'as shown in FIG.

  At this time, since the irradiation area 7 by the LED flash does not move, a deviation occurs between the imaging range P ′ and the irradiation area 7. Therefore, the irradiation area correction unit 60 controls the light emission amounts of the plurality of LEDs 55 to reduce the deviation between the imaging range P ′ and the irradiation area 7. Here, FIG. 11 shows an example of the arrangement of the LEDs 55 and the light emission pattern, and FIG. 12 shows an irradiation example of each LED 55 being exposed.

  As shown in FIG. 11, a plurality of LEDs 55 arranged vertically and horizontally are set by selecting, for example, two rows at the lower end and the left end by selecting “3”, 4 × 4 at the center, “1” and the remaining “2”. When the optical axis of the optical system 10 is shifted to the lower left as shown in FIG. 10B, the LEDs 55 arranged in the direction in which the optical axis is shifted, that is, the LEDs 55 set to “3” are replaced with the LEDs of FIG. As shown in the pattern 3, the light intensity is gradually increased from the start to the end of exposure, and the LEDs 55 arranged in the direction opposite to the direction in which the optical axis is shifted, that is, the LEDs 55 set to “2” are As shown in pattern 2, the light intensity is gradually reduced between the start and end of exposure. In this way, by controlling the amount of light emitted from the LED 55 in accordance with the movement of the optical axis of the photographing optical system 10, the deviation between the irradiation region 7 of the LED flash and the photographing range P can be achieved without mechanical driving. Can be reduced.

  In the above embodiment, the LED flash having a plurality of LEDs (light emitting elements) 55 irradiates the entire subject in the shooting range P, but the present invention is not limited to this. The LED flash may have a whole irradiation mode for irradiating the subject in the photographing range P as a whole and a divided irradiation mode for partially irradiating the subject in the photographing range P. Here, FIG. 13 and FIG. 14 each show an example of irradiation when photographing in the divided irradiation mode. FIG. 13A shows normal shooting, FIG. 14B shows camera shake, FIG. 14A shows camera shake correction, and FIG. 13B shows camera shake and irradiation area correction.

  In the divided irradiation mode, for example, as shown in FIG. 13A, when the object detection unit 46 detects, for example, the face F from the image data, the LED 55 corresponding to the detected area of the face F is caused to emit light. Can be set as the irradiation region L0.

  In this way, when the subject is divided and irradiated, if a camera shake occurs during shooting, the shooting range P becomes a shooting range P ′ as shown in FIG. The irradiation area L0 also blurs to the lower left to become the irradiation area L0 ′, and the irradiation area L0 ′ shifts from the face F area. Further, as shown in FIG. 14A, when the photographing range P ′ is corrected by the camera shake correction unit 45 at the time of photographing, the irradiation range L0 remains the irradiation range L0 that deviates from the face F region.

  When the irradiation range L is the entire subject, the deviation of the irradiation range due to camera shake is not noticeable, but the irradiation range L0 irradiated in a divided manner may change the irradiation target due to movement due to camera shake. large. Therefore, the irradiation area correction unit 60 corrects the irradiation range L0 only when the LED flash is set to the divided irradiation mode.

  The correction method changes the irradiation range L <b> 0 by controlling each of the plurality of LEDs 55 by turning it on / off in the same manner as in the above embodiment. As a result, as shown in FIG. 14B, the imaging range P ′, that is, the optical axis of the imaging optical system 10 is set in the irradiation range L0 based on the camera shake amount detected by the camera shake detection unit 44 in the same manner as the correction. Correction can be performed. As a result, the irradiation area can be corrected only when the influence of camera shake is large, and power consumption can be reduced.

  In this way, the irradiation area correction unit 60 corrects the irradiation area. When the correction of the irradiation area is started, as shown in FIG. 6, the shutter drive unit 24 opens and closes the shutter to perform exposure and photographing (step S30). When the exposure is completed, the LED flash control unit 53 The LED 55 is stopped (step S31), and photographing is finished.

  If the irradiation area correction unit 60 is not set to ON in step S27 (step S27; NO), the LED control unit 53 irradiates the LED 55 toward the subject (step S32), and the irradiation area correction unit. The process proceeds to step S30 without performing the correction by 60, and the subsequent processes are performed to complete the photographing. In this way, photographing with the digital camera 1-2 is performed.

  By correcting camera shake optically based on the amount of camera shake and correcting the irradiation area of the LED flash as described above, even if the optical angle of the photographic optical system is tilted by the camera shake correction, the angle of view changes. The irradiation area of the light emitting means can be corrected following the change in the angle of view. Thereby, even if optical camera shake correction is performed in the digital camera, it is possible to irradiate the subject with appropriate light.

  In the above embodiment, camera shake correction by the camera shake correction unit 45 is performed not only during exposure but also during display of a through image on the liquid crystal monitor 35. However, it may be performed only during exposure.

  In the above-described embodiment, the description has been mainly made of correcting the irradiation position of the LED flash. However, the present invention is not limited to this, and the size of the irradiation area of the LED flash may be changed. Here, FIG. 15 shows an example of changing the size of the irradiation region.

  In general, the longer the exposure time, the higher the possibility of camera shake and the greater the amount of camera shake. Accordingly, the amount of camera shake correction when the camera shake correction unit 45 performs camera shake correction, that is, the amount of movement of the shooting range also increases.

  Therefore, as shown in FIG. 15 (a), the LED flash irradiates the irradiation region L to the subject in the shooting range P during normal shooting, while the light emission is performed based on the exposure time, that is, the LED flash emission time. When the time is long, the irradiation region L ′ is changed to be larger than the irradiation region L as shown in FIG. For example, the configuration shown in FIGS. 8, 9, and 11 can be used to change the irradiation region.

  In this way, even if the shooting range P and the irradiation area L of the LED flash are shifted due to the camera shake correction by the camera shake correction unit 45, shooting is performed if the shift amount is smaller than the increment in the shift direction of the irradiation area L. A subject in the range P can be irradiated.

  Even in the case of shooting in the divided irradiation mode, the light emission amount and / or the irradiation region of the LED 55 may be changed based on the exposure time, that is, the light emission time of the LED flash. FIG. 16 shows an example of changing the light emission amount and / or the irradiation area of the LED 55 at the time of photographing in the divided irradiation mode.

  As shown in FIG. 16A, for example, the object detection unit 46 detects a face as an object from the image data, and causes the LED 55 corresponding to the detected area of the face F to emit light, thereby setting the face area as the irradiation area L1. In this case, when the exposure time, that is, the light emission time is relatively short (for example, 1/60 seconds to 1/15 seconds), the irradiation region L1 ′ is changed to be slightly larger than the irradiation region L1, and the light emission time is relatively long In (for example, 1/15 second to 1/4 second), the irradiation area is changed to an irradiation area L1 ″ larger than the irradiation area L1 ′.

  In this way, even if the LED flash irradiation area L1 is shifted from the face F to be irradiated by the camera shake correction by the camera shake correction unit 45, the shift amount is smaller than the increment in the shift direction of the irradiation area L1. Since the face area can be irradiated, it is possible to prevent the main part such as the face from becoming dark.

  If the light emission time is relatively long, the light emission amount of the LED 55 may be reduced. By doing so, it is possible to prevent the portion other than the face irradiated with light, that is, the background from becoming bright when the LED flash irradiation area L1 deviates from the face F to be irradiated by camera shake correction.

  In the above-described embodiment, on / off of the irradiation area correction unit 60 can be arbitrarily set. However, the present invention is not limited to this, and only when the camera shake correction unit 45 is set to on. Alternatively, the irradiation area correction unit 60 may be set to ON. FIG. 17 shows a flowchart of a series of processing of this photographing.

  As shown in FIG. 17, first, the CPU 50 determines whether or not the camera shake correction unit 45 is set to ON (step S40). When the camera shake correction unit 45 is set to ON (step S40; YES), the irradiation area correction unit 60 is set to ON (step S41). Since the irradiation area correction unit 60 is automatically turned on when the camera shake correction unit 45 is turned on in this way, the irradiation area can be corrected only when necessary. Power consumption for correction can be reduced.

  Note that steps S42 to S47 in FIG. 17 are the same as steps S21 to S26 in FIG. 6, and steps S48 to S51 in FIG. 17 are the same as steps S28 to S31 in FIG. .

  Further, the irradiation region correction unit 60 may be driven only when the zoom magnification of the zoom lens 10b is larger than a predetermined value (for example, focal length f = 80 mm: 35 mm conversion), that is, may be turned on. When the zoom magnification is low, the subject shooting range is wide and the subject movement is small. However, when the zoom magnification is high, the subject shooting range is narrow and the subject movement is large. Accordingly, camera shake is more likely to occur when the zoom magnification is large. Therefore, by turning on the irradiation region correction unit 60 only when the zoom magnification is large, power consumption for correction of the irradiation region can be reduced. .

  Further, the irradiation area correction unit 60 may be driven only when the F value of the diaphragm 11 of the photographing optical system 10 is larger than a predetermined value (for example, F value is F5.0 times), that is, may be turned on. When the F value of the diaphragm 11 is large, the shutter speed becomes slower than when the F value is small, and thus camera shake is likely to occur. Therefore, by turning on the irradiation region correction unit 60 only when the F value of the diaphragm 11 is large, it is possible to reduce power consumption required for correction of the irradiation region.

  Note that the imaging apparatus of the present invention is not limited to the digital camera of the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

Functional block diagram of digital camera The graph which shows the relationship between the light emission amount and light emission time in LED and Xe, and exposure time Flowchart of a series of shooting processes using a digital camera Functional block diagram of a digital camera of another embodiment The figure which shows an example of the optical axis and imaging | photography field angle of an imaging optical system, the optical axis of LED, and an irradiation area | region Another flowchart of a series of shooting processes by a digital camera (A) perspective view (b) top view (c) side view of an LED flash that mechanically changes the irradiation area Side view of another LED flash that mechanically changes the illumination area Side view of yet another LED flash that mechanically changes the illumination area Diagram showing the relationship between the irradiation area and imaging range The figure which shows an example of arrangement | positioning and the light emission pattern of LED The figure which shows an example of the light emission pattern of each LED under exposure The figure which shows an example of the irradiation at the time of imaging | photography in division | segmentation irradiation mode, (a) At the time of normal imaging | photography (b) At the time of camera shake occurrence The figure which shows another example of irradiation when image | photographing by division | segmentation irradiation mode, (a) At the time of camera shake correction (b) At the time of camera shake and irradiation area correction The figure which shows an example in the case of changing the magnitude | size of an irradiation area | region The figure which shows an example in the case of changing the emitted light quantity and / or irradiation area | region of LED at the time of imaging | photography in division | segmentation irradiation mode Another flowchart of a series of shooting processes

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Imaging device 10 Imaging optical system 100 Imaging part (imaging means)
39 AE processing unit (exposure calculation means)
44 Camera shake detection unit (camera shake detection means)
45 Camera shake correction unit (camera shake correction means, optical camera shake correction means)
46 Object detection unit (object detection means)
53 LED flash controller 54 LED drive circuit 55 LED
53, 54, 55 LED flash (light emitting means, first light emitting means)
56 Xe tube flash controller 57 Xe tube drive circuit 58 Xe tube 56, 57, 58 Xe tube flash (second light emitting means)
60 Irradiation area correction unit (irradiation area correction means)

Claims (10)

Imaging means for generating an image signal by forming an image of a subject on an imaging device via a photographing optical system;
Camera shake detection means for detecting the amount of camera shake;
Optical camera shake correction means for correcting camera shake by moving at least a part of the photographing optical system based on the camera shake amount detected by the camera shake detection means;
A light emitting means for continuously emitting light to the subject;
An imaging apparatus comprising: an irradiation area correction unit that corrects an irradiation area of the light emitting unit based on a camera shake amount detected by the camera shake detection unit. The light emitting means has a plurality of light emitting elements,
The imaging apparatus according to claim 1, wherein the irradiation region correction unit changes the irradiation region by controlling light emission amounts of the plurality of light emitting elements. The light emitting means has a plurality of light emitting elements, and a divided irradiation mode for irradiating the subject in a divided manner by controlling light emission amounts of the plurality of light emitting elements, and an overall irradiation mode for irradiating the subject as a whole. And
The imaging apparatus according to claim 1, wherein the irradiation region correcting unit changes the irradiation region only when the light emitting unit is in the divided irradiation mode.   The imaging apparatus according to claim 1, wherein the irradiation area correction unit mechanically changes the irradiation area.   The imaging apparatus according to claim 1, wherein the irradiation region correction unit changes a size of the irradiation region based on a light emission time of the light emitting unit. An object detection means for detecting a predetermined object from the image signal;
The irradiation area correction means changes the light emission amount and / or the irradiation area of the light on the object detected by the object detection means in the subject based on the light emission time of the light emission means. The image pickup apparatus according to claim 1, wherein the image pickup apparatus is provided. The optical camera shake correction means and the irradiation area correction means have switching means that can be switched on / off,
The imaging apparatus according to claim 1, wherein the irradiation region correction unit is turned on only when the optical camera shake correction unit is turned on. The imaging optical system includes a zoom lens,
The imaging apparatus according to claim 1, wherein the irradiation area correction unit is driven only when a zoom magnification of the zoom lens is larger than a predetermined value.   The imaging according to any one of claims 1 to 6, wherein the irradiation area correction unit is driven only when an F value of an aperture included in the photographing optical system is larger than a predetermined value. apparatus. In an imaging apparatus that includes a light emitting unit that continuously emits light to a subject and generates an image signal by forming an image of the subject on an imaging element via a photographing optical system.
Detect the amount of camera shake,
An irradiation area correction method comprising: correcting at least a part of the imaging optical system based on a detected amount of camera shake to optically correct camera shake and correcting an irradiation area of the light emitting means.

Images