JP5351298B2 - Compound eye imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compound-eye imaging apparatus that can image an excellent 3D image regardless of whether a finger rests on a lens or not. <P>SOLUTION: Two imaging parts allocated to positions in the longer direction of a camera body image two images having a parallax each other, where the imaging part having a taking lens farthest from a release button is set as a reference imaging part. An AE detection part or AWB detection part performs photometry of the brightness of a subject or obtains a white balance gain based on an image signal acquired through the reference imaging part respectively. The detected detection result is applied to an AE control or AWB correction of the other imaging part. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a compound eye imaging apparatus, and more particularly to a compound eye imaging apparatus that captures two images having parallax with each other.

  2. Description of the Related Art Conventionally, in a compound-eye imaging apparatus having a function of capturing a stereoscopically viewable three-dimensional image (3D image) composed of parallax images having parallax with each other, a photographic lens of a bending optical system using a prism for miniaturizing the apparatus body (Hereinafter referred to as “bending lens”) has been proposed (Patent Document 1).

  Further, the two focus lenses are driven simultaneously, an evaluation value (AF evaluation value) indicating the contrast of the image is calculated for each predetermined feed amount, and the maximum value of the AF evaluation value is detected at the position of the focus lens previously detected. A compound eye imaging device that sets the other focus lens has been proposed (Patent Document 2). For example, one focus lens performs AF search from close to infinity, and the other focus lens performs AF search from infinity to close so that the AF operation can be completed efficiently in a short time. Yes.

JP 2009-48181 A JP 2006-162990 A

  The compound eye imaging device described in Patent Document 1 is miniaturized by using a bent lens, but the left and right bent lenses are designed to increase the stereoscopic effect and the sense of reality (in order to increase the baseline length). It is arrange | positioned at the left-right edge part of an apparatus main body, respectively.

  Therefore, when the grip portion (end portion on the release button side) of the apparatus main body is gripped, there is a problem that the finger of the gripped hand is easily caught on the bent lens on the release button side.

  If a finger is placed on one of the left and right lenses, there is a problem that the amount of light incident on the left and right lenses changes greatly, and the brightness of the left eye image and the right eye image changes greatly. Similarly, the focus adjustment and white balance correction of the left eye image and the right eye image are different and there is a problem that a good 3D image cannot be obtained.

  On the other hand, the compound-eye imaging apparatus described in Patent Document 2 uses a retractable lens barrel (FIG. 1, Paragraph [0016] of Patent Document 2), so that there is no problem of fingering on the lens during photographing. Therefore, it is impossible to reduce the thickness and size of the device. Moreover, since the compound-eye imaging device described in Patent Document 2 is configured so that the position of the other focus lens is aligned with the focus position of the focus lens previously focused, the reference imaging unit is fixed. I can't.

  In a conventional digital camera, a live view image (through image) is displayed on a liquid crystal monitor on the back of the camera in order to confirm the composition of a subject before actual imaging. However, a 3D through image is two-dimensional ( There is a problem that finger catching is difficult to confirm as compared to a through image of 2D). This is because an image with a finger and an image without a finger are superimposed and displayed when there is no finger on the other lens even if there is a finger on one lens.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a compound eye imaging apparatus capable of capturing a good 3D image regardless of whether or not a finger is caught on the lens.

In order to achieve the above object, a compound-eye imaging device according to one aspect of the present invention is two imaging means that are arranged at positions in the longitudinal direction of the device main body and capture two images having parallax with each other, Two imaging means each having a photographic lens that does not protrude from the front surface of the apparatus main body or has a small protrusion, a release button disposed on the apparatus main body, and an imaging means having a photographic lens farthest from the release button Metering means for metering the brightness of the subject based on the image signal acquired in the above; exposure control means for controlling the exposure of the two imaging means based on the brightness of the subject metered by the photometry means; wherein the center position between the two imaging means taking lens, away from the position of the release button relative to the longitudinal center position of the main body It is arranged so as to be offset.

  Of the two image pickup means, an image pickup means having a taking lens farthest from the release button is used as a reference image pickup means, and the photometry means is configured to detect a subject based on an image signal acquired through the reference image pickup means. The brightness is metered. Since the reference imaging means has the taking lens farthest from the release button, the finger of the hand operating the release button does not get caught on the taking lens. Since the light metering unit measures the brightness of the subject based on the image signal acquired from the image pickup unit (reference image pickup unit) having the image pickup lens without the finger hold, it can perform good photometry. In addition, since the exposure of the two image pickup means is controlled based on the photometric result, two images picked up by the two image pickup means can be picked up with appropriate exposure, respectively, and The brightness can be adjusted and a good 3D image can be obtained.

In addition, since the center position between the two photographing lenses is arranged to be shifted in the direction away from the position of the release button with respect to the center position in the longitudinal direction of the apparatus body, the apparatus body is manually operated by operating the release button. When gripping the device, a grip portion for gripping with the hand can be secured in the apparatus main body.

  In the compound eye imaging device according to still another aspect of the present invention, a calculating unit that calculates a white balance correction value based on an image signal acquired through an imaging unit having a photographing lens farthest from the release button; White balance correction means for correcting the white balance of the parallax images acquired from the two imaging means based on the white balance correction value calculated by the calculation means can be further provided.

  According to still another aspect of the present invention, the reference imaging means of the two imaging means has a photographing lens that is farthest from the release button, so the finger of the hand that operates the release button is the photographing lens. It wo n’t hang on. As a result, the calculating means can calculate an appropriate white balance correction value based on the image signal obtained from the reference imaging means, and the white balance of the two images acquired from the two imaging means. And a good 3D image can be obtained.

  In the compound-eye imaging device according to still another aspect of the present invention, the calculation means for calculating the white balance correction value is a color balance sensitivity between an imaging means having an imaging lens farthest from the release button and another imaging means. A storage unit for storing a ratio, and a white balance correction value for a parallax image acquired from another imaging unit can be calculated based on the calculated white balance correction value and the sensitivity ratio read from the storage unit; . Thereby, the individual difference between the two imaging means can be absorbed and the white balance can be made uniform.

  In the compound-eye imaging device according to still another aspect of the present invention, the two photographing lenses can each be a photographing lens of a bending optical system.

According to the present invention, the photographic lens that is disposed at a position in the longitudinal direction of the apparatus main body and that does not protrude from the front surface of the apparatus main body or has a photographic lens with a small protrusion, of the photographic lens that is farthest from the release button The image pickup unit having the image pickup unit is used as a reference image pickup unit, and exposure control (AE control) of the two image pickup units is performed based on an image signal acquired through the reference image pickup unit, or white balance of an image having two parallaxes is performed. Since the correction (AWB correction) is performed, a good 3D image can be captured regardless of whether or not the other photographing lens is hooked. In addition, since the center position between the photographing lenses of the two imaging means is shifted in the direction away from the position of the release button with respect to the center position in the longitudinal direction of the apparatus main body, it is possible to operate the release button with a hand. When gripping the device main body, a grip portion for gripping with the hand can be secured in the device main body.

FIG. 1 is a view showing an appearance of a compound eye imaging apparatus according to the present invention. FIG. 2 is a front view of the compound eye image pickup apparatus shown in FIG. FIG. 3 is a block diagram showing a first embodiment of a compound eye imaging apparatus according to the present invention. FIG. 4 is a flowchart showing the first embodiment of the present invention. FIG. 5 is a block diagram of the main part of the first embodiment of the present invention. FIG. 6 is a program diagram applied during exposure control according to the present invention. FIG. 7 is a block diagram showing a second embodiment of the compound eye imaging apparatus according to the present invention. FIG. 8 is a flowchart showing the second embodiment of the present invention. FIG. 9 is a diagram used for explaining the focus adjustment according to the present invention. FIG. 10 is a block diagram of the main part of the second embodiment of the present invention. FIG. 11 is a block diagram showing a third embodiment of the compound eye imaging device according to the present invention. FIG. 12 is a flowchart showing the third embodiment of the present invention. FIG. 13 is a block diagram of the main part of the third embodiment of the present invention.

  Embodiments of a compound eye imaging apparatus according to the present invention will be described below with reference to the accompanying drawings.

[Appearance of compound eye imaging device]
FIG. 1 is a diagram showing the appearance of a compound eye imaging device according to the present invention, and FIGS. 1A to 1D are a top view, a front view, a rear view, and a left side view of the compound eye imaging device, respectively. FIG. 2 is a front view of the compound eye imaging apparatus shown in FIG.

  This compound-eye imaging device (compound-eye camera) 10 is a digital camera capable of recording and reproducing 2D / 3D still images and 2D / 3D moving images. As shown in FIG. 1, the upper surface of a thin rectangular parallelepiped camera body Are provided with a release button 11 and a zoom button 12.

  On the front surface of the camera body, a lens barrier 13 having a width substantially equal to the width in the left-right direction of the camera body is disposed so as to be movable in the vertical direction of the camera body, and the lens barrier 13 is moved in the vertical direction. By doing so, the front surfaces of the pair of left and right photographing lenses 14-1 and 14-2 can be opened and closed simultaneously as shown in FIG. Note that bent lenses are used as the photographing lenses 14-1 and 14-2.

  Further, on the surface of the lens barrier 13, finger-hanging convex portions 13 </ b> A are formed in the left-right direction. The finger-hanging convex portion 13A serves as a finger hook when operating the lens barrier 13, and also serves to prevent the finger from being caught on the lens during imaging. The camera power supply can be turned on / off in conjunction with the opening / closing operation of the lens front surface by the lens barrier 13.

  On the back of the camera body, a 3D liquid crystal monitor 16 is disposed at the center. The liquid crystal monitor 16 can display two images (right-eye image and left-eye image) as directional images each having a predetermined directivity by a parallax barrier. The 3D liquid crystal monitor 16 uses a lenticular lens, or can display a right eye image and a left eye image individually by wearing dedicated glasses such as polarized glasses or liquid crystal shutter glasses. Is applicable.

  Various operation switches are arranged on the left and right of the liquid crystal monitor 16 (FIG. 1C). The operation switch 18A is a switch for switching between still image shooting and moving image shooting, and the operation switch 18B is a switch for switching between 2D shooting and 3D shooting. The operation switch 18C is a seesaw key that functions as both a MENU / OK button and a playback button, the operation switch 18D is a multifunction cross key, and the operation switch 18E is a DISP / BACK key.

  The MENU / OK button is an operation switch having both a function as a menu button for instructing to display a menu on the screen of the liquid crystal monitor 16 and a function as an OK button for instructing confirmation and execution of selection contents. It is. The playback button is a button for switching from the shooting mode to the playback mode. The cross key is an operation switch for inputting instructions in four directions, up, down, left, and right. A macro button, a flash button, a self-timer button, or the like is assigned to the menu key. When a menu is selected, the menu screen is displayed. Function as a switch (cursor moving operation means) for selecting an item from the menu or instructing selection of various setting items from each menu. The left / right key of the cross key functions as a frame advance (forward / reverse feed) button in the playback mode. The DISP / BACK key is used for switching the display form of the liquid crystal monitor 16, canceling the instruction content on the menu screen, or returning to the previous operation state.

As shown in FIG. 2, when C _{1 is} the center of the camera body in the left-right direction and C ₂ is the center of the left and right photographing lenses 14-1 and 14-2, C ₂ is shown by a length L than C ₁ . 2 is shifted to the right side (right side when viewed from the front side). That is, each imaging lens 14-1 and 14-2, the lens center C ₂ with respect to the center C ₁ of the camera body is disposed displaced in the direction away from the release button 11 side, thereby the camera right It is possible to secure a grip portion when the release button 11 is operated by gripping with.

[First Embodiment]
FIG. 3 is a block diagram showing a first embodiment of the compound eye imaging device (compound eye camera) 10.

  As shown in FIG. 3, this compound-eye camera 10 mainly includes two imaging units 20-1, 20-2, a central processing unit (CPU) 32, an AE (Automatic Exposure) photometric unit 33, and the release button described above. 11, an operation unit 34 including a zoom button 12 and various operation switches, a display control unit 36, a liquid crystal monitor 16, a recording control unit 38, a compression / decompression processing unit 42, a digital signal processing unit 44, an AF (Auto Focus: automatic) It includes a focus detection unit 46, an AWB (Automatic White Balance) detection unit 48, a VRAM 50, a RAM 52, a flash memory 54, a ROM 56, an exposure setting calculation unit 58, and the like. Note that the imaging units 20-1 and 20-2 capture two parallax images, a left-eye image and a right-eye image, that have parallax with each other, but there may be three or more imaging units 20.

  The imaging unit 20-1 that captures an image for the left eye includes a prism (not shown), a bending lens including a focus lens and a zoom lens 21, an optical unit including a diaphragm 22 and a mechanical shutter 23, and a solid-state imaging device (CCD). 24, an analog signal processing unit 25, an A / D converter 26, an image input controller 27, a lens driving unit 28 for driving the optical unit, an aperture driving unit 29, a shutter control unit 30, and a CCD 24. CCD control unit 31 is provided. Note that the imaging unit 20-2 that captures the image for the right eye has the same configuration as the imaging unit 20-1 that captures the image for the left eye, and thus the description of the specific configuration is omitted.

  The CPU 32 controls the overall operation of the compound eye camera according to a predetermined control program based on the input from the operation unit 34. The ROM 56 stores a control program executed by the CPU 32 and various data necessary for the control, and the flash memory 54 stores various setting information related to the operation of the compound eye camera such as user setting information. The VRAM 50 is a memory for temporarily storing display image data to be displayed on the liquid crystal monitor 16, and the RAM 52 includes a calculation work area for the CPU 32 and a temporary storage area for image data.

  The focus lens and zoom lens 21 included in the bent lens are driven by the lens driving unit 28 and moved back and forth along the optical axis. The CPU 32 controls the driving of the lens driving unit 28 to control the position of the focus lens so as to adjust the focus so that the subject is in focus, and in response to a zoom command from the zoom button 12 in the operation unit 34. To control the zoom lens position for zooming.

  The diaphragm 22 is constituted by an iris diaphragm, for example, and is driven by the diaphragm drive unit 29 to operate. The CPU 32 controls the aperture amount (aperture value) of the aperture 22 via the aperture drive unit 29 and controls the amount of light incident on the CCD 24.

  The mechanical shutter 23 determines the exposure time at the CCD 24 by opening and closing the optical path, and prevents unwanted light from entering the CCD 24 when reading an image signal from the CCD 24 to prevent smear. The CPU 32 outputs a shutter close signal synchronized with the exposure end time corresponding to the shutter speed to the shutter control unit 30 to control the mechanical shutter 23.

  The CCD 24 is constituted by a two-dimensional color CCD solid-state imaging device. A large number of photodiodes are two-dimensionally arranged on the light receiving surface of the CCD 24, and color filters are arranged in a predetermined arrangement on each photodiode.

  The optical image of the subject formed on the CCD light receiving surface via the optical unit having the above configuration is converted into a signal charge corresponding to the amount of incident light by the photodiode. The signal charge accumulated in each photodiode is sequentially read out from the CCD 24 as a voltage signal (image signal) corresponding to the signal charge based on a drive pulse given from the CCD control unit 31 according to a command from the CPU 32. The CCD 24 has an electronic shutter function, and the exposure time (shutter speed) is controlled by controlling the charge accumulation time in the photodiode. The electronic shutter controls the charge accumulation start time corresponding to the shutter speed, and the exposure end time (charge accumulation end time) is controlled by closing the mechanical shutter 23. In the present embodiment, the CCD 24 is used as the image pickup device, but an image pickup device having another configuration such as a CMOS sensor can also be used.

  The analog signals R, G, and B read from the CCD 44 are subjected to correlated double sampling (CDS) and amplification by the analog signal processing unit 25, and then the R, G, and B analog signals are output by the A / D converter 26. Converted to a digital signal.

  The image input controller 27 includes a line buffer having a predetermined capacity, temporarily stores R, G, and B image signals A / D converted by the A / D converter 26, and then stores the RAM 52 via the bus 60. To store.

  In the 3D shooting mode, the CPU 32 controls the imaging unit 20-2 that captures the right-eye image in the same manner as the imaging unit 20-1 that captures the left-eye image.

  The AE metering unit 33 calculates the subject brightness necessary for AE control based on the image signal captured when the release button 11 is half-pressed. The exposure setting calculation unit 58 sets the shutter speed (exposure time), aperture value, and photographing sensitivity in the two imaging units 20-1 and 20-2 based on the photometric value measured by the AE photometric unit 33.

  The AF detection unit 46 integrates the absolute value of the high-frequency component of the image signal in the AF area captured when the release button 11 is half-pressed, and outputs this integrated value (AF evaluation value) to the CPU 32. The CPU 32 moves the focus lens from the closest position to the infinity side, searches for a focus position where the AF evaluation value detected by the AF detection unit 46 is maximum, and moves the focus lens to the focus position. Adjust the focus on the subject (main subject). The AWB detection unit 48 automatically obtains the light source type (color temperature of the object scene) based on the R, G, and B image signals acquired at the time of the main imaging, and R, G, The corresponding white balance gain is read out from the table storing the B white balance gain (white balance correction value).

  Details of the AE photometry unit 33, the AF detection unit 46, the AWB detection unit 48, and the exposure setting calculation unit 58 will be described later.

  The digital signal processing unit 44 interpolates a spatial shift of color signals such as R, G, and B accompanying a white balance correction circuit, a gradation conversion processing circuit (for example, a gamma correction circuit), and a color filter array of a single-plate CCD. And function as image processing means including a processing circuit for aligning the position of each color signal, a contour correction circuit, a luminance / color difference signal generation circuit, and the like, and a predetermined signal for the R, G, B image signals stored in the RAM 52 Process. That is, the R, G, and B image signals are multiplied by the white balance gain detected by the AWB detection unit 48 in the digital signal processing unit 44 and subjected to white balance correction. After predetermined processing such as gamma correction is performed, the signal is converted into a YC signal including a luminance signal (Y signal) and a color difference signal (Cr, Cb signal). The YC signal processed by the digital signal processing unit 44 is stored in the RAM 52.

  The compression / decompression processing unit 42 compresses the YC signal stored in the RAM 52 in accordance with a command from the CPU 32 during recording on the recording medium 40, and decompresses the compressed compressed data recorded on the recording medium 40. To YC signal. The recording control unit 38 converts the compressed data compressed by the compression / decompression processing unit 42 into an image file of a predetermined format (for example, a 3D still image is an MP (multi-picture) format image file) and records it on the recording medium 40. Alternatively, the image file is read from the recording medium 40.

  The liquid crystal monitor 16 is used as an image display unit for displaying captured images, and is used as a GUI (graphical user interface) during various settings. The liquid crystal monitor 16 is used as an electronic viewfinder for confirming the angle of view in the shooting mode. When displaying a 3D image on the liquid crystal monitor 16, the display control unit 36 alternately displays the left-eye image and the right-eye image held in the VRAM 50 one pixel at a time. By the parallax barrier provided in the liquid crystal monitor 16, the left and right images alternately arranged pixel by pixel are visually recognized separately by the left and right eyes of the user observing from a predetermined distance. This enables stereoscopic viewing.

<AE control>
FIG. 4 is a flowchart showing the first embodiment of the present invention, and shows the procedure for calculating the exposure setting value in each imaging unit.

  In FIG. 4, when the release button 11 is half-pressed, the AE metering unit 33 performs subject brightness metering based on an image signal acquired from an imaging unit having a lens farthest from the release button 11 (step S10). ). In other words, the AE metering unit 33 is acquired from the imaging unit having the lens farthest from the release button 11 (in this embodiment, the imaging unit 20-1 that captures the image for the left eye having the photographing lens 14-1). The subject luminance is measured by calculating the integrated average value of the image signals. The photometric method is not limited to average photometry, and various photometric methods such as center-weighted photometry and spot photometry can be applied.

  The metering value measured by the AE metering unit 33 is input to the exposure setting calculation unit 58 as shown in FIG. All other inputs of the exposure setting calculation unit 58 include the amount of aperture shift and mechanical shutter delay with respect to the reference values of the aperture 22 and the mechanical shutter 23 of the imaging unit, and the exposure setting calculation unit 58 Based on the input photometric value, the aperture shift amount of all the image pickup units, and the shift amount of the mechanical shutter delay, the exposure setting values of all the image pickup units are calculated (steps S12 to S20).

  Note that the exposure setting calculation unit 58 sets the sensitivity / aperture shift amount of all the imaging units with respect to the sensitivity / aperture reference value stored in the storage unit 58A in advance, and all the imaging units with respect to the mechanical shutter delay reference value. From the amount of mechanical shutter displacement, the corresponding sensitivity / aperture displacement amount and mechanical shutter delay amount can be input.

  Subsequently, the exposure setting calculation unit 58 obtains an exposure value (shooting EV value) from the photometric value obtained by the above correction, and based on this exposure value and a preset program diagram, the shooting sensitivity, aperture value, and exposure time ( The shutter speed is obtained (step S14).

  FIG. 6 shows an example of a program diagram. For example, when the exposure value is 9, according to the program diagram of FIG. 4, the exposure time is 1/125 (second) (TV7), the photographing sensitivity is ISO400, and the aperture value is F2.9 (AV3).

  Next, the exposure setting calculation unit 58 has other lenses for the exposure setting value (shooting sensitivity / aperture value / exposure time) for the imaging unit having the lens farthest from the release button 11 obtained as described above. It is reflected as an exposure setting value for the imaging unit (step S16).

  Here, as the imaging sensitivity of each imaging unit to be set, the sensitivity is corrected by the amount of deviation from the sensitivity / aperture reference value of the imaging unit, and the corrected sensitivity is set (step S18).

  Further, the mechanical shutter planned closing position of the mechanical shutter of each imaging unit is corrected by the amount of deviation from the mechanical shutter delay reference value of the mechanical shutter of the imaging unit (step S20).

  The exposure setting calculation unit 58 passes the exposure setting values of all the imaging units calculated as described above to the CPU 32, and the CPU 32 determines the aperture 22, electronic shutter, and the like based on the exposure setting values set for each imaging unit. The mechanical shutter 23 and the photographing sensitivity are controlled. The shooting sensitivity is set by setting the amplifier gain of the analog signal processing unit 25.

  In the compound-eye camera configured with a bent lens as described above, the subject brightness is measured based on the image signal acquired from the imaging unit having the lens farthest from the release button, so that the lens side that is difficult to catch on the finger ( When the camera is held by one hand, photometry can be performed by the imaging unit on the lens side that does not hold the finger 100%, so that the photometry / exposure accuracy is improved. In addition, by correcting the amount of deviation from the reference value of sensitivity / aperture / mechanical shutter delay of each image pickup unit, individual differences in each image pickup unit can be absorbed and exposure control can be performed with high accuracy. A high-quality stereoscopic image can be performed.

[Second Embodiment]
FIG. 7 is a block diagram showing a second embodiment of the compound eye camera according to the present invention. In addition, the same code | symbol is attached | subjected to the part which is common in 1st Embodiment shown in FIG. 3, and the detailed description is abbreviate | omitted.

  The compound eye camera of the second embodiment shown in FIG. 7 is provided with an AE / AWB detection unit 49 instead of the AE photometry unit 33 and the AWB detection unit 48 shown in FIG. 3, and instead of the exposure setting calculation unit 58. Is different from the first embodiment in that a focus range calculation unit 62 is provided. The AE / AWB detection unit 49 performs the same detection as the AE photometry unit 33 and the AWB detection unit 48 shown in FIG.

<AF control>
FIG. 8 is a flowchart showing a second embodiment of the present invention, and shows a focus adjustment method in each imaging unit.

  In FIG. 8, when the release button 11 is half-pressed, the AF detection unit 46 integrates the absolute value of the high frequency component of the image signal in the AF area acquired from the imaging unit having the lens farthest from the release button 11. The integrated value (AF evaluation value) is output to the CPU 32. The CPU 32 moves the focus lens from the closest position to the infinity side, searches for the focus position P1 at which the AF evaluation value detected by the AF detection unit 46 is maximum, and moves the focus lens to the focus position P1. Thus, the focus adjustment to the subject (main subject) is performed (step S30).

  FIG. 9A is a diagram showing the relationship between the search position of the focus lens of the first lens farthest from the release button 11 and the AF evaluation value. The focus lens has a focus position at which the AF evaluation value is maximum. Moved to P1. By obtaining the in-focus position P1 with the focus adjusting means of the first lens farthest from the release button 11, it is possible to obtain an in-focus position that is not affected by finger grip. Since there is a grip on the release button 11 side, there is a possibility that a finger is put on the lens close to the release button 11.

  Subsequently, a variable i indicating the imaging unit of the compound eye camera is initially set to 2 (step S32).

  As shown in FIG. 10, the focus range calculation unit 62 includes the in-focus position Pi of the first lens farthest from the release button 11, the i-th lens and the first lens that are previously investigated and stored in the storage unit 62 </ b> A. The focus shift amount Dfi with the lens and the focus adjustment width of the search margin (Ni, Fi) are input.

  The focus range calculation unit 62 determines the center position Pi of the focus adjustment means of the i-th lens as P1- based on the in-focus position P1 of the first lens and the focus shift amount Dfi between the i-th lens and the first lens. Obtained as Dfi (step S34, FIG. 9B).

  Further, the focus range calculation unit 62 passes the obtained center position Pi of the focus adjustment means of the i-th lens and the focus adjustment width for the search margin stored in the storage unit 62A to the CPU 32. The CPU 32 causes the focus lens of the i-th lens to perform an AF search within the range of the Ni pulse on the near side and the Fi pulse (search margin due to temperature, posture, etc.) on the far side centered on the center position Pi (step). S36).

  The CPU 32 determines the presence / absence of a focus position Pi ′ at which the AF evaluation value is maximum based on the AF evaluation value acquired by the AF search by the focus lens of the i-th lens (step S38), and the focus position Pi ′. If there is a focus position Pi ′, the focus lens of the i-th lens is moved to the focus position Pi ′ (step S40). If there is no focus position Pi ′, the focus lens of the i-th lens is calculated. The position Pi is moved (step S42).

  Subsequently, the CPU 32 determines whether or not the focus adjustment of all the lenses has been completed (step S44). If the focus adjustment of all the lenses has not been completed, the variable i is incremented by 1 (step S46). In step S34, the same focus adjustment as described above is performed for the next i-th lens. Note that when there are three or more imaging units, the process may return to step S34 according to the above flow line, but in the case of two imaging units, the process does not return to step S34.

  In the compound-eye camera configured with a bent lens as described above, the focus is adjusted based on the image signal acquired from the imaging unit having the lens farthest from the release button. In this case, the focus can be adjusted based on the image signal acquired from the image pickup unit on the lens side that is not 100% finger-fingered, so that a correct in-focus position can be obtained and high-precision focus adjustment can be performed. In addition, the i-th lens takes into account the shift amount (Dfi) of the focus lens between the lens farthest from the release button and the i-th lens, and the search margin (Ni, Fi) due to temperature, posture, etc. By adjusting the focus of this lens, there is a high possibility that a correct focus position (a focus position for focusing on the same subject) can be obtained.

  Furthermore, even when the i-th in-focus position cannot be obtained due to some cause (for example, the cause of finger catching on the lens), another focus lens is placed at the position obtained from the previously obtained amount of shift of the focus lens. By moving it, the possibility of being in focus can be increased. As described above, a highly visible stereoscopic image can be captured.

  In the above embodiment, the AF search is performed from close to infinity. However, for example, when shooting in landscape mode, the AF search may be performed from infinity to close.

[Third Embodiment]
FIG. 11 is a block diagram showing a third embodiment of the compound-eye camera according to the present invention. In addition, the same code | symbol is attached | subjected to the part which is common in 1st Embodiment shown in FIG. 3, and the detailed description is abbreviate | omitted.

  The compound eye camera of the third embodiment shown in FIG. 11 is provided with an AWB detection unit 64 instead of the AWB detection unit 48 shown in FIG. 3 and an AE detection unit 51 instead of the AE photometry unit 33. Further, the second embodiment is different from the first embodiment in that a WB calculation unit 66 is provided instead of the exposure setting calculation unit 58. The AE detection unit 51 performs the same detection as the AE photometry unit 33 shown in FIG.

<AWB correction>
FIG. 12 is a flowchart showing a third embodiment of the present invention, and shows an AWB correction method in each imaging unit.

  In FIG. 12, the AWB detection unit 64 is actually captured by fully pressing the release button 11, and is acquired from an imaging unit having a lens farthest from the release button 11 among the image signals of a plurality of viewpoints stored in the RAM 52. An image signal for one screen is captured, the screen of this image signal is divided into a plurality of divided areas (for example, 8 × 8), R, G, B signals are integrated for each divided area, and the integrated value R / G Color information (R / G, B / G) of each divided area expressed by the ratio of / B is calculated (step S50). The AWB detection unit 64 is shaded, cloudy, and clear from the distribution of the obtained color information (R / G, B / G) of each divided area on the color space with the R / G axis and the B / G axis as coordinate axes. The light source type is estimated from the light source types such as the fluorescent lamp and the light bulb (step S52). As a method for estimating the light source type, known methods described in JP 2000-224608 A, JP 2004-304695 A, and the like can be used.

  After estimating the light source type, the AWB detection unit 64 obtains a white balance gain (white balance correction value) according to the estimated light source type (step S53). The white balance gain is obtained by preparing a white balance gain table for performing white balance correction optimal for the light source type and reading the white balance gain corresponding to the obtained light source type. be able to.

  Subsequently, a variable i indicating the imaging unit of the compound eye camera is initially set to 2 (step S54).

  As shown in FIG. 13, the white balance gain of the first lens farthest from the release button 11 is input from the AWB detection unit 64 to the WB calculation unit 66 and a storage unit 66A that stores the imaging unit sensitivity ratio. From all the lenses, the sensitivity ratio of the imaging unit with the lens farthest from the release button can be input.

  The WB calculation unit 66 determines the white balance of the i-th lens based on the sensitivity ratio between the first lens farthest from the release button and the i-th lens and the white balance gain obtained for the first lens. A gain is calculated (step S56).

  Now, the white balance gain of the first lens is WBR1 / WBG1 / WBB1 for each of the R, G, and B signals, and the sensitivity ratio between the imaging unit of the first lens and the imaging unit of the i-th lens is GRi / GGi / Assuming GBi, the white balance gain (WBRi / WBGi / WBBi) of the i-th lens can be obtained by the following [Equation 1].

[Equation 1]
WBRi = WBR1 * GRi
WBGi = WBG1 * GGi
WBBi = WBB1 * GBi
The WB calculation unit 66 determines whether or not the calculation of the white balance gain of all the lenses has been completed (step S58). If the calculation of the white balance gain of all the lenses has not been completed, the variable i is set. 1 is incremented by 1 (step S60), the process proceeds to step S56, and the white balance gain is calculated in the same manner as described above for the next i-th lens. When there are three or more image capturing units, the process may return to step S56 according to the above flow line, but in the case of two image capturing units, the process does not return to step S56.

  In the compound-eye camera configured with a bent lens as described above, the white balance gain is calculated based on the image signal acquired from the imaging unit having the lens farthest from the release button, so that the lens side that is difficult to catch on with the finger The white balance gain can be calculated based on the image signal acquired from the imaging unit (the lens side that is not 100% finger-clamped when it is held by one hand), and the correct white balance gain can be obtained. It can be carried out. In addition, by using the sensitivity ratio between the imaging unit of the lens farthest from the release button and the imaging unit of the other lens, which is obtained in advance, the white balance gain of the lens farthest from the release button is used to calculate another lens. By calculating the white balance gain, it is possible to match the white balance by absorbing individual differences in the imaging units of the respective lenses. As a result, a highly visible stereoscopic image can be obtained.

[Others]
The present invention is not limited to those shown in the first to third embodiments, but may be a combination of the embodiments as appropriate.

  The photographing lens applied to the present invention is not limited to a bent lens, and any lens may be used as long as the lens does not protrude from the front surface of the camera.

  It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Compound eye imaging device (compound camera), 11 ... Release button, 13 ... Lens barrier, 13A ... Convex part, 16 ... Liquid crystal monitor, 20-1, 20-2 ... Imaging part, 21 ... Focus lens and zoom lens, 22 ... Aperture, 23 ... Mechanical shutter, 24 ... CCD, 25 ... Analog signal processing unit, 28 ... Lens driving unit, 29 ... Aperture driving unit, 30 ... Shutter control unit, 31 ... CCD control unit, 32 ... Central processing unit (CPU) , 34... Operation unit, 44... Digital signal processing unit, 46... AF detection unit, 48 and 64... AWB detection unit, 52. , 62... Focus range calculation unit, 66... WB calculation unit

Claims (4)

Two imaging units that are disposed at positions in the longitudinal direction of the apparatus main body and that capture two images having parallax with each other, each having an imaging lens that does not protrude from the front surface of the apparatus main body or has a small protrusion Means,
A release button disposed in the apparatus body;
Photometric means for measuring the brightness of a subject based on an image signal acquired through an imaging means having a taking lens farthest from the release button;
Exposure control means for controlling the exposure of the two imaging means based on the brightness of the subject measured by the photometry means,
A compound-eye imaging device in which the center position between the photographing lenses of the two imaging means is shifted in a direction away from the position of the release button with respect to the longitudinal center position of the device body. Calculating means for calculating a white balance correction value based on an image signal acquired through an imaging means having a taking lens farthest from the release button;
White balance correction means for correcting white balance of parallax images acquired from the two imaging means based on the white balance correction value calculated by the calculation means;
The compound eye imaging apparatus according to claim 1, further comprising:   The calculation means for calculating the white balance correction value has storage means for storing a sensitivity ratio of color balance between an imaging means having an imaging lens farthest from the release button and another imaging means, and the calculated white balance The compound eye imaging apparatus according to claim 2, wherein a white balance correction value for a parallax image acquired from another imaging unit is calculated based on the balance correction value and the sensitivity ratio read from the storage unit.   The compound eye imaging apparatus according to any one of claims 1 to 3, wherein each of the two photographing lenses is a bending optical system photographing lens.

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