JP2013109079A - Compound-eye imaging device, focusing method of the same and electronic information device - Google Patents

Abstract

An optical system for capturing a pair of left and right parallax images with different angles of view can be easily focused at an appropriate position, thereby reducing the control time required for automatic focusing in a short time. A compound eye imaging device capable of accurately acquiring a pair of left and right parallax images forming a stereoscopic image is realized.
SOLUTION: First and second imaging units 12 and 22 that image a subject so as to obtain a pair of left and right parallax images, and first and second optical systems 11 and 21 corresponding to the imaging units 12 and 22, respectively. And a signal processing unit 31 that determines the focus of each optical system based on an image in the focus evaluation region in each parallax image, and based on the parallax of both the imaging units 12 and 22, The relative position of the second focus evaluation area with respect to the left-eye image is adjusted so that the relative position of the first focus evaluation area matches the relative position of the first focus evaluation area with respect to the right-eye image.
[Selection] Figure 2

Description

  The present invention relates to a compound-eye imaging device, a focusing method for a compound-eye imaging device, and an electronic information device, and in particular, optimum automatic focusing is performed by an optical system of two imaging units that capture a pair of parallax images forming a stereoscopic image. The present invention relates to a compound-eye imaging apparatus configured to be performed, a method for performing such optimum autofocusing, and an electronic information device including such a compound-eye imaging apparatus.

  2. Description of the Related Art Conventionally, there is a compound eye imaging device that captures a subject so that a pair of parallax images (that is, a right-eye image and a left-eye image) for forming a stereoscopic image can be obtained. In such a compound-eye imaging device, the subject is imaged by two imaging units that obtain a right-eye image and a left-eye image. Therefore, focusing (focusing) is performed by two optical systems corresponding to the two imaging units. ) Is necessary.

  However, in such a compound-eye imaging device, since the two imaging units simultaneously photograph the same subject, an automatic focusing operation, that is, an autofocus operation (AF operation) is separately performed by the optical system corresponding to the two imaging units. There is a problem that it is inefficient, and Patent Documents 1 and 2 disclose measures against such a problem.

  FIG. 10 is a diagram illustrating a compound eye imaging device disclosed in Patent Document 1. In FIG.

  The compound-eye imaging apparatus 200a includes a first video camera (imaging camera) 201 and a second video camera (imaging camera) 202, and optical systems 201a and 202a such as a lens group provided in each video camera. doing.

  Here, these optical systems 201a and 202a have adjustment mechanisms (not shown) for adjusting each imaging condition such as an aperture mechanism, a focus mechanism, and a zoom mechanism. The compound-eye imaging apparatus 200a includes a control unit (not shown) for controlling the adjustment mechanism as described above, and a focusing arithmetic circuit (for detecting a focus state in at least one optical system of each video camera). The control means drives the focus mechanism in the optical system of the first video camera and the second video camera from the output (that is, focal length information) of the focus calculation circuit. It is configured. In FIG. 10, reference numeral 204 denotes a member that integrally supports the first and second video cameras 201 and 202, and 203 denotes a viewfinder that displays the video output of one of the video cameras.

  In the compound-eye imaging apparatus 200a having such a configuration, the focus mechanism in both the optical systems of the first video camera 201 and the second video camera 202 is driven based on the output of the focusing calculation circuit. Then, quick focusing is performed without shifting the focusing timing of the left and right video cameras.

  FIG. 11 is a diagram for explaining the stereoscopic camera (compound eye imaging device) disclosed in Patent Document 2.

  The stereoscopic camera 200b includes first and second imaging units (imaging cameras) 220a and 220b that image a subject. The first and second imaging units 220a and 220b include first and second zoom lenses 211 and 220, first and second diaphragms 212 and 221, first and second focus lenses 213 and 222, and First and second image sensors 214 and 223 are included. Here, the first imaging unit 220a captures the subject so that one of a pair of parallax images (a right-eye image and a left-eye image) for forming a stereoscopic image is obtained. The unit 220b captures the subject so that the other of a pair of parallax images (right-eye image and left-eye image) for forming a stereoscopic image is obtained. The first and second focus lenses 213 and 222 are driven by a lens motor and configured to move between the near point Pn and the far point Pi along the optical axes La and Lb.

  When such an automatic focusing operation (AF operation) is started, the first focus lens 213 moves from the near point Pn to the far point Pi in the direction of arrow A, and the second focus lens 222 moves far away. It moves in the direction of arrow B from the point Pi toward the near point Pn. At this time, an AF evaluation value (a value indicating the degree of focus) is calculated for each predetermined feed amount of each focal lens, and both focus points to the focus lens position where the maximum value of the AF evaluation value is detected first. The AF operation is completed by aligning the lens position.

  Thus, in the stereoscopic camera disclosed in Patent Document 2, one focus lens of the first and second imaging units 220a and 220b is placed on the macro side, and the other focus lens of these imaging units is placed on the telephoto side. Simultaneously, the two focus lenses are moved in the opposite directions to calculate the AF evaluation value for each focus lens, and the positions of both focus lenses are aligned with the lens position of the focus lens where the AF evaluation value is maximized first. An AF operation can be performed efficiently in a short time.

JP-A-7-15749 JP 2006-162990 A

  By the way, in a compound eye imaging device, depending on the lens position in the optical system of the imaging camera, there is a possibility that the images captured by the pair of left and right imaging cameras become images with different angles of view. If the lens position is on the macro side of the macro side and the macro side, the position of the subject may be greatly different in a pair of parallax images obtained by the respective imaging cameras.

  For example, FIG. 12 shows a state in which the angle of view is shifted between the left-eye image (FIG. 12A) and the right-eye image (FIG. 12B) obtained by the compound-eye projection apparatus.

  In the left-eye image LVa shown in FIG. 12A, the foreground person image H included in the background is located on the right side of the imaging region (field of view of the imaging camera) LSa, while shown in FIG. In the right-eye image RVa, the foreground person image H included in the background is located to the left of the imaging region (field of view of the imaging camera) RSa.

  In such a state, when automatic focusing is performed with each imaging camera corresponding to both eyes using the right-eye image RVa, imaging for capturing the left-eye image at a position where the right-eye image RVa is in focus. The focus of the camera is set, and the focus position of the imaging camera for the left-eye image may not be the correct focus position for the left-eye image having a different angle of view from the right-eye image.

  That is, when the angle of view differs between the left-eye image and the right-eye image, an AF evaluation value (autofocus evaluation value) originally obtained from the left-eye image and an AF evaluation value (autofocus evaluation value) obtained from the right-eye image ) Will be different. For this reason, when the focus position of both the imaging camera for the left-eye image and the imaging camera for the right-eye image is set using the AF evaluation value obtained from either the right-eye image or the left-eye image, one imaging camera Thus, the parallax image obtained in (1) becomes out of focus with respect to the subject, and a clear stereoscopic image cannot be obtained.

  The present invention has been made to solve the above-described problems, and easily focuses the optical system for capturing each of a pair of left and right parallax images having different angles of view at appropriate positions. A compound eye imaging device capable of acquiring a pair of left and right parallax images for obtaining a clear stereoscopic image while suppressing a control time required for automatic focusing in a short time, and a focusing method of the compound eye imaging device, Another object of the present invention is to obtain an electronic information device using such a compound eye imaging device.

  A compound-eye imaging apparatus according to the present invention is a compound-eye imaging apparatus that obtains a pair of parallax images forming a stereoscopic image of a subject by photographing the subject, and images the subject so that one of the pair of parallax images is obtained. A first imaging unit; a second imaging unit that images the subject so that the other of the pair of parallax images is obtained; and a first optical system that introduces light from the subject into the first imaging unit A second optical system that introduces light from the subject into the second imaging unit, and a focal point of the first optical system is determined based on an image in the first focus evaluation region in the one parallax image. And a focus determination unit that determines a focus of the second optical system based on an image in the second focus evaluation region in the other parallax image, and the focus determination unit includes the first imaging unit. And the second imaging unit based on the parallax between the second imaging unit and the second imaging unit The relative position of the second focus evaluation area with respect to the other parallax image is adjusted so that the relative position of the point evaluation area matches the relative position of the first focus evaluation area with respect to the one parallax image. Yes, and the above objective is achieved.

  According to the present invention, in the compound eye imaging device, the focus determination unit determines a relative position of the first focus evaluation region with respect to the one parallax image based on an operation signal of an operator, and It is preferable to have an evaluation area setting unit that matches the relative position of the second focus evaluation area with the relative position of the first focus evaluation area with respect to the one parallax image.

  According to the present invention, in the compound eye imaging device, the evaluation area setting unit sets the first focus evaluation area at an arbitrary position on the one parallax image based on an operation signal of the operator. It is preferable to be configured.

  The present invention provides the compound-eye imaging device, comprising: a display screen that displays an image; and a touch panel that is arranged on the display screen and is divided into a plurality of partitioned areas, and is obtained by imaging the subject. A monitor unit that displays the pair of parallax images on the display screen so that a stereoscopic image of the subject is recognized, and the evaluation region setting unit includes a monitor unit configured to display one of the pair of parallax images displayed on the display screen. It is preferable that an area corresponding to the partitioned area designated by the operator's touch operation among the plurality of partitioned areas is set as the first focus evaluation area.

  In the compound eye imaging device according to the present invention, it is preferable that the focus determination unit is configured to set the first focus evaluation region at the center of the one parallax image.

  According to the present invention, in the compound eye imaging device, the focus determination unit is configured to evaluate a first degree for evaluating a degree of focus of the first optical system with respect to an image in the first focus evaluation region. A first evaluation value calculation unit that calculates a focus evaluation value; a first focus position calculation unit that calculates a focus position in the first optical system based on the first focus evaluation value; and the second A second evaluation value calculation unit for calculating a second focus evaluation value for evaluating the degree of focus of the optical system with respect to the image in the second focus evaluation region; and the second focus It is preferable to have a second focal position calculation unit that calculates a focal position in the second optical system based on the evaluation value.

  In the compound eye imaging device according to the present invention, the first focus evaluation value is obtained by integrating the luminance value of each pixel constituting the image in the first focus evaluation area over the entire first focus evaluation area. The second focus evaluation value is obtained by integrating the luminance value of each pixel constituting the image in the second focus evaluation area over the entire second focus evaluation area. The obtained value is preferred.

  In the compound eye imaging device according to the present invention, the first focus evaluation value is obtained by integrating a luminance difference between adjacent pixels in an image in the first focus evaluation area over the entire first focus evaluation area. The second focus evaluation value is obtained by integrating the luminance difference between adjacent pixels in the image in the second focus evaluation area over the entire second focus evaluation area. The obtained value is preferred.

  In the compound eye imaging apparatus according to the present invention, the optical axis of the first optical system and the optical axis of the second optical system are parallel, and the parallax between the first imaging unit and the second imaging unit Is preferably a separation distance between the optical axis of the first optical system and the optical axis of the second optical system.

  According to the present invention, in the compound eye imaging device, the first optical system includes a first focus lens, and the first focus lens is moved by moving the first focus lens on the optical axis of the first optical system. The second optical system includes a second focus lens, and an optical axis of the second optical system of the second focus lens is adjusted on the optical axis of the second optical system. It is preferable that the focal position of the second optical system is adjusted by movement of the second optical system.

  In the focusing method of the compound-eye imaging device according to the present invention, one of a pair of parallax images forming a stereoscopic image of a subject is captured by a first imaging unit, and the other of the pair of parallax images is captured by a second imaging unit. A method of focusing a compound-eye imaging device for imaging, wherein the focus of a first optical system that introduces light of the subject into the first imaging unit is within a first focus evaluation region in the one parallax image Determine based on the image, and determine the focus of the second optical system that introduces light from the subject into the second imaging unit based on the image in the second focus evaluation region in the other parallax image Including a step, in which the relative position of the second focus evaluation region with respect to the other parallax image is based on the parallax between the first imaging unit and the second imaging unit. Match the relative position of the first focus evaluation area to the image So that is intended to adjust the relative position of the focus evaluation area of the second with respect to the parallax images of the other side, the objects can be achieved.

  An electronic information device according to the present invention is an electronic information device including an imaging unit, and uses the above-described compound eye imaging device according to the present invention as the imaging unit, thereby achieving the above-described object. The

  Next, the operation will be described.

  In the present invention, in a compound eye imaging device in which one of a pair of parallax images forming a stereoscopic image of a subject is captured by a first imaging unit and the other of the pair of parallax images is captured by a second imaging unit. The focus of the first optical system that introduces the light of the subject into one imaging unit is determined based on the image in the first focus evaluation region in the one parallax image, and the subject is sent to the second imaging unit. A focal point of the second optical system that introduces light from the second parallax image is determined based on an image in the second focus evaluation region in the other parallax image, and at this time, the first imaging unit and the second imaging unit Based on the parallax with the other unit, the relative position of the second focus evaluation region with respect to the other parallax image matches the relative position of the first focus evaluation region with respect to the one parallax image. Adjusting the relative position of the second focus evaluation area with respect to the parallax image Therefore, it is possible to easily adjust the focus of each optical system for capturing one parallax image and another parallax image with different angles of view to an appropriate position, thereby shortening the control time required for automatic focusing. It is possible to capture an image that can form a clear stereoscopic image as a pair of parallax images while suppressing.

  As described above, according to the present invention, it is possible to easily focus the optical system for capturing each of the pair of left and right parallax images having different angles of view to an appropriate position, which is necessary for automatic focusing. Using a compound eye imaging device capable of acquiring a pair of left and right parallax images for obtaining a clear stereoscopic image while keeping the control time short, a focusing method for the compound eye imaging device, and such a compound eye imaging device An electronic information device can be realized.

FIG. 1 is a diagram illustrating an appearance of a compound eye imaging apparatus according to Embodiment 1 of the present invention. FIG. 2 is a diagram illustrating a circuit configuration of the compound eye imaging device according to Embodiment 1 of the present invention. FIG. 3 is a diagram for explaining a compound eye imaging device according to Embodiment 1 of the present invention, a state in which a subject is imaged by this compound eye imaging device (FIG. 3A), and imaging of a subject by this compound eye imaging device. 3 shows a pair of parallax images (FIG. 3B and FIG. 3C) obtained by. FIG. 4 is a diagram for explaining the effect of the first embodiment of the present invention. The positional relationship between the left-eye image and the AF evaluation region (FIGS. 4A and 4C), and the right-eye image and the AF evaluation region. (FIGS. 4B and 4D). FIG. 5 is a diagram for explaining an AF operation in the compound eye imaging apparatus according to Embodiment 1 of the present invention. FIG. 6 is a diagram for explaining a digital signal processing circuit constituting the compound eye imaging apparatus according to Embodiment 1 of the present invention. FIG. 7 is a diagram illustrating the flow of imaging processing in the compound eye imaging device according to Embodiment 1 of the present invention. FIG. 8 is a diagram for explaining another example (FIGS. 8A and 8B) in which an AF evaluation area is set for one parallax image in the compound-eye imaging device according to Embodiment 1 of the present invention. is there. FIG. 9 is a block diagram illustrating a schematic configuration example of an electronic information device using the compound-eye imaging device of Embodiment 1 as an imaging unit as Embodiment 2 of the present invention. FIG. 10 is a diagram illustrating a compound eye imaging device disclosed in Patent Document 1. In FIG. FIG. 11 is a diagram illustrating a stereoscopic image capturing apparatus (compound eye imaging apparatus) disclosed in Patent Document 2. FIG. 12 is a diagram for explaining a problem in the conventional compound eye imaging device disclosed in the above-mentioned patent document.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a diagram illustrating an appearance of a compound eye imaging apparatus according to Embodiment 1 of the present invention.

  The compound-eye imaging apparatus 100 according to the first embodiment captures a subject T (see FIG. 3A) so as to obtain a pair of parallax images that form a stereoscopic image. The first optical system 11 and the second optical system 21 are incorporated, and an operation button 102 is provided on the upper surface of the apparatus housing 101.

  FIG. 2 is a diagram illustrating a specific configuration of the compound-eye imaging apparatus according to Embodiment 1 of the present invention.

  The compound-eye imaging apparatus 100 includes a first imaging unit 12 that captures an image of the subject T so as to obtain one (right-eye image) Rv (FIG. 3C) of a pair of parallax images, and a pair of parallax images of the subject T. 2 (image for left eye) Lv (FIG. 3B) and a second image pickup unit 22 for picking up an image, and the first image pickup unit 12 uses the first optical system 11 to shoot the subject. Light L <b> 1 from T is introduced, and light L <b> 2 from the subject T is introduced into the second imaging unit 22 by the second optical system 21.

  Here, the first optical system 11 includes a first focus lens (not shown), and the first optical system 11 is moved by moving the first focus lens on the optical axis of the first optical system 11. The second optical system 21 includes a second focus lens (not shown) and is on the optical axis of the second optical system 21 of the second focus lens. The focal position of the second optical system 21 is adjusted by the movement at. The compound eye imaging apparatus 100 is provided with a first actuator 16 that moves a first focus lens that constitutes the first optical system 11, and moves a second focus lens that constitutes the second optical system 21. A second actuator 26 is provided. The first actuator 16 is driven by the drive signal Ad1 from the first actuator drive unit 15, and the second actuator 26 is driven by the drive signal Ad2 from the second actuator drive unit 25. Yes.

  The first imaging unit 12 and the second imaging unit 22 use a solid-state imaging device such as a CCD image sensor or a CMOS image sensor, and the optical axis of the first optical system 11 is the first one. The optical axis of the second optical system 21 constitutes the second imaging unit 22, which coincides with the normal line set at the center of the light receiving surface of the solid-state imaging device (right imaging device) constituting the imaging unit 12. This coincides with the normal line set at the center of the light receiving surface of the solid-state image sensor (left image sensor). The optical axis of the first optical system 11 and the optical axis of the second optical system 21 are parallel, and the parallax between the first imaging unit 12 and the second imaging unit 22 is the light of the first optical system 11. This is the distance between the axis and the optical axis of the second optical system 21.

  FIG. 3 is a diagram for explaining a compound eye imaging device according to Embodiment 1 of the present invention, a state in which a subject is imaged by this compound eye imaging device (FIG. 3A), and imaging of a subject by this compound eye imaging device. 3 shows a pair of parallax images (FIG. 3B and FIG. 3C) obtained by.

  The compound-eye imaging apparatus 100 determines the focus of the first optical system 11 based on the image in the first focus evaluation region Raf in one parallax image (right-eye image) Rv, and the focus of the second optical system 21. Is determined based on the image in the second focus evaluation region Laf in the other parallax image (left-eye parallax image) Lv, and a monitor that displays a stereoscopic image obtained by imaging Part 40. Here, the monitor unit 40 includes, for example, a liquid crystal display panel and a parallax barrier, and is configured to display a pair of parallax images so that a stereoscopic image can be recognized.

  Based on the parallax between the first imaging unit 12 and the second imaging unit 22, the signal processing unit 31 has a relative position of the second focus evaluation region Laf with respect to the other parallax image (left-eye image) Lv. Adjusting the relative position of the second focus evaluation region Laf to the other parallax image (left-eye image) Lv so as to match the relative position of the first focus evaluation region Raf to the parallax image (right-eye image) Rv of The luminance value Rd1 of each pixel constituting the image in the first focus evaluation area Raf is sequentially output over the first focus evaluation area Raf, and each pixel constituting the image in the second focus evaluation area Laf is output. A digital signal processing circuit 32 that sequentially outputs the luminance value Rd2 over the second focus evaluation region Laf is provided. In FIG. 3B and FIG. 3C, Ra is an imaging region by the first imaging unit 12 (that is, a field of view of the first imaging unit 12 determined by the first optical system 11), and La is the first. 2 is an imaging region (that is, a field of view of the second imaging unit 22 determined by the second optical system 21) by the second imaging unit 22.

  In addition, the signal processing unit 31 integrates the luminance value Rd1 of each pixel constituting the image in the first focus evaluation area Raf over the first focus evaluation area Raf, and the first focus evaluation area Raf. The first AF integration unit 13 that outputs the focus evaluation value Daf1 and the luminance value Rd2 of each pixel constituting the image in the second focus evaluation region Laf are integrated over the second focus evaluation region Laf. A lens position signal is calculated by calculating the lens position based on the second AF integrating unit 23 that outputs the focus evaluation value Daf2 in the second focus evaluation area Laf and the focus evaluation value Daf1 in the first focus evaluation area Raf. A first lens position calculation unit 14 that outputs Dp1 and a second lens that calculates a lens position based on the focus evaluation value Daf2 in the second focus evaluation region Laf and outputs a second lens position signal Dp2 Position calculator And a 4.

  In the first and second AF integrating units 13 and 23, the first and second focus evaluation values Daf1 and Daf2 are moved along the optical axis of the focus lens in the first and second optical systems 11 and 21, respectively. It is obtained for each of a plurality of measurement points set in advance in the path. In the first and second lens position calculation units 14 and 24, the measurement point having the largest first and second focus evaluation values Adf1 and Adf2 is the lens position. The lens position information Dp1 and Dp2 indicating the lens position is output to the first and second actuator driving units 15 and 25.

  The first focus evaluation value Aaf1 is a value for evaluating the degree to which the first optical system 11 is focused on the image in the first focus evaluation region Raf. The focus evaluation value Aaf2 is a value for evaluating the degree to which the second optical system 21 is focused on the image in the second focus evaluation region Laf. In addition, when the operator presses the operation button (shutter button) 102 of the apparatus housing 101 halfway, the actuator driving units 15 and 25 are the focus lenses of the optical systems 11 and 12 according to the operation signal Sop from the operation button 102. 11a is moved along the optical axis from the movement start point Sp to the movement end point Ep as shown in FIG. 5, and when the lens position information Dp1 and Dp2 are input from the lens position calculation units 14 and 24, this lens position The focus lens is moved to the position indicated by the information. In FIG. 5, F indicates the magnitude of the focus evaluation value Aaf1, and Lp indicates the lens position between the movement start point Sp and the movement end point Ep.

  FIG. 6 is a diagram for explaining a digital signal processing circuit constituting the compound eye imaging apparatus according to Embodiment 1 of the present invention.

  The digital signal processing circuit 32 includes a first frame memory 32 a that stores image data Dv1 of a right-eye image obtained by imaging the subject T by the first imaging unit 12, and the subject T by the second imaging unit 22. First and second AF evaluations for the second frame memory 32b for storing the image data Dv2 of the left-eye image obtained by imaging, and the images Rv and Lv stored in the respective frame memories 32a and 32b, respectively. The AF evaluation area setting unit 32e that sets the areas Raf and Laf, and the pixel value Px1 of the pixel in the first AF evaluation area Raf in the image Rv stored in the frame memory 32a are read, and the first AF evaluation area Raf is read A first luminance value generation unit 32c that outputs the luminance value Rd1 of the constituent pixels, and an image L stored in the frame memory 32b And a second luminance value generation unit 32d that reads out the pixel value Px2 of the pixel in the second AF evaluation area Laf and outputs the luminance value Rd2 of the pixel constituting the second AF evaluation area Laf. .

  Here, the AF evaluation area setting unit 32e sets the first focus evaluation area Raf to be positioned at the center of the right-eye image Rv stored in the first frame memory 32a, and sets the second frame. For the left eye image Lv stored in the memory 32b, the second focus evaluation area Laf is used, and the relative position of the second focus evaluation area Laf to the left eye image Lv is the first focus evaluation for the right eye image Rv. The configuration is set so as to coincide with the relative position of the region Raf.

  Next, the operation will be described.

  FIG. 7 is a diagram for explaining the flow of imaging processing by the compound eye imaging apparatus according to the first embodiment.

  As shown in FIG. 3A, when the operator images the subject T with the compound eye imaging device 100 of the first embodiment, while viewing the image displayed on the display screen V of the monitor unit 40 of the compound eye imaging device 100. When the operation button (shutter button) 102 is half-pressed in the direction in which the compound-eye imaging device 100 is imaged, the operation button 102 receives a signal for instructing the focus position as the operation signal Sop from the operator. It is output to the first and second actuator driving units 15 and 25 (step S1).

  Subsequently, the AF evaluation area setting unit 32e, for the first imaging unit 12 that captures the right-eye image Rv of the pair of parallax images that form the stereoscopic image of the subject T, is the center of the imaging area Ra. Is set to the first AF evaluation area Raf, and the second imaging unit 22 that captures the left-eye image Lv of the pair of parallax images forming the stereoscopic image of the subject T is set in the imaging area La. The second AF evaluation area Laf is set at a position displaced in the horizontal direction from the center by a distance equivalent to the parallax of the imaging units 12 and 22 (step S2). Thereby, the relative position of the first AF evaluation region Raf with respect to the image Rv imaged by the first imaging unit 12 and the relative position of the second AF evaluation region Laf with respect to the image Lv imaged by the second imaging unit 22. The position will substantially match.

  Here, the setting of the first AF evaluation area Raf with respect to the imaging area (the visual field of the first imaging section 12 determined by the first optical system 11) Ra of the first imaging section 12 is made from the AF evaluation area setting section 32e. Is performed on the first frame memory 32a that stores the image data Dv1 of the right-eye image Rv obtained from the first imaging unit 12, and the first AF of the first frame memory 32a is performed. Image data of an area corresponding to the evaluation area Raf is used for the AF operation. In addition, the setting of the second AF evaluation area Laf with respect to the imaging area of the second imaging section 22 (the field of view of the second imaging section 22 determined by the second optical system 21) is made from the AF evaluation area setting section 32e. In response to the command signal Ea2, the second AF is performed on the second frame memory 32b that stores the image data Dv2 of the image Lv for the left eye obtained from the second imaging unit 22, and the second AF evaluation of the second frame memory 32b is performed. Image data of an area corresponding to the area Laf is used for the AF operation.

  After the AF evaluation area is set in this way, the AF operation is started (step S3).

  The first actuator 16 moves the focus lens of the first optical system 11 from the movement start point Sp to the movement end point Ep by the drive signal Ad1 from the first actuator drive unit 15, and from this movement start point Sp. An AF evaluation value is obtained for each preset measurement point up to the movement end point Ep.

  Specifically, when the focus lens is located at one measurement point in the first optical system 11, the image data Dv1 obtained from the first imaging unit 12 is stored in the first frame memory 32a, and the first In the first luminance value generation unit 32c, the luminance of each pixel constituting the image of the AF evaluation area Raf based on the image data of the area corresponding to the first AF evaluation area Raf in the first frame memory 32a. The value Rd1 is generated. The luminance value Rd1 is integrated over the entire AF evaluation region Raf by the first AF integration unit 13, and the integrated value of the luminance value Rd1 is used as the first AF evaluation value Daf1 for the measurement point at the first lens position. It is output to the calculation unit 14.

  The first lens position calculation unit 14 compares the first AF evaluation value Daf1 obtained as described above at each measurement point, and determines the measurement point at which the largest first AF evaluation value Daf1 is obtained. The in-focus position of the first optical system 11 is determined, and first lens position information Dp1 indicating the in-focus position is output to the first actuator driving unit 15. Thereby, the first actuator driving unit 15 drives the first actuator 16 so that the focus lens in the first optical system 11 moves to the in-focus position.

  Similarly, the second actuator 26 moves the focus lens of the second optical system 21 from the movement start point Sp toward the movement end point Ep by the drive signal Ad2 from the second actuator driving unit 25, and this movement An AF evaluation value is obtained for each preset measurement point between the start point Sp and the movement end point Ep.

  Specifically, when the focus lens is located at one measurement point in the second optical system 21, the image data Dv2 obtained from the second imaging unit 22 is stored in the second frame memory 32b, and the second In the second luminance value generation unit 32d, the luminance of each pixel constituting the image of the AF evaluation area Laf based on the image data of the area corresponding to the second AF evaluation area Laf of the second frame memory 32b. The value Rd2 is generated. The luminance value Rd2 is integrated over the entire AF evaluation area Laf by the second AF integration unit 23, and the integrated value of the luminance value Rd2 is used as the second AF evaluation value Daf2 for the measurement point at the second lens position. It is output to the calculation unit 24.

  The second lens position calculation unit 24 compares the second AF evaluation value Daf2 obtained as described above at each measurement point, and determines the measurement point at which the largest second AF evaluation value Daf2 is obtained. The in-focus position of the second optical system 21 is determined, and second lens position information Dp2 indicating the in-focus position is output to the second actuator driving unit 25. As a result, the second actuator driving unit 25 drives the second actuator 26 so that the focus lens in the second optical system 21 moves to the in-focus position (step S4).

  Thereafter, when the operator completely pushes down the operation button (shutter button) 102, a shooting command signal is output from the operation button to the control unit 32f as the operation signal Sop, and the focus of the optical system corresponding to each of the imaging units 12 and 22 is obtained. In the state in which the images are matched, the imaging units 12 and 22 capture the subject, and the image data Dv1 and Dv2 of the right-eye image and the left-eye image obtained thereby are the frame memories 32a corresponding to the respective imaging units. 32b, and the image data RDv1 and RDv2 stored in the frame memories 32a and 32b are output as digital outputs under the control of the control unit 32f.

  As described above, in the first embodiment, in the compound-eye imaging apparatus 100 that obtains a pair of parallax images (a right-eye image and a left-eye image) that form a stereoscopic image of a subject by photographing the subject, a right-eye image Rv is obtained for the subject. A first imaging unit 12 for imaging, a second imaging unit 22 for imaging the subject so as to obtain the left-eye image Lv, and a first optical system for introducing light from the subject into the first imaging unit 12 11, the second optical system 21 that introduces light from the subject into the second imaging unit 22, and the focus of the first optical system 11 is an image in the first focus evaluation region Raf in the right-eye image Rv. And a signal processing unit 31 that determines the focal point of the second optical system 21 based on the image in the second focus evaluation region Laf in the left-eye image Lv, and includes the first imaging unit 12 and the first imaging unit 12. Based on the parallax between the two imaging units 22 Thus, the relative position of the second focus evaluation area with respect to the left-eye image is adjusted so that the relative position of the second focus evaluation area with respect to the left-eye image matches the relative position of the first focus evaluation area with respect to the right-eye image. Therefore, it is possible to easily adjust the focus of each optical system for capturing right-eye images and left-eye images with different angles of view to appropriate positions, thereby reducing the control time required for automatic focusing in a short time. Meanwhile, it is possible to capture an image that can form a clear stereoscopic image as a pair of parallax images.

  In other words, in the first embodiment, in the compound-eye imaging device, both the focusing lenses of the first and second optical systems are operated simultaneously to perform focusing separately. Therefore, the right-eye image and the left-eye that form a stereoscopic image A clear image can be obtained together with the image for use.

  In addition, when the focusing lens (AF operation) is separately operated by operating the focusing lens in the optical systems of both imaging units in this way, an area (AF evaluation area) for acquiring image data used for automatic focusing is obtained. Depending on the parallax between the left and right imaging units, there may be very different cases. However, in the compound-eye imaging device of this embodiment, the relative positions of the AF evaluation areas for the right-eye image and the left-eye image are matched. Since the AF evaluation area is set in the optical system of the imaging unit that acquires the image data used for automatic focusing by the optical system of the imaging unit that captures the image for the left eye, the optical system of the imaging unit that captures the area for the image for the left eye Thus, the image data used for automatic focusing can be substantially matched with the area in the right-eye image. In other words, automatic focusing in the optical system of the imaging unit that captures the image for the left eye and automatic focusing in the optical system of the imaging unit that captures the image for the left eye are performed using image data for appropriate AF evaluation. Therefore, the AF operation in the compound eye imaging apparatus can be performed with high accuracy.

  For example, as shown in FIGS. 4A and 4B, the AF evaluation regions Raf and Laf are set to be positioned at the center of each image for the right-eye image Rv and the left-eye image Lv. In some cases, depending on conditions, as shown in these drawings, image data of different parts of the subject image may be used to focus the optical system corresponding to each imaging unit. Then, as shown in FIGS. 4C and 4D, the AF evaluation areas Raf and Laf are substantially the same as the images in the AF evaluation area for the right-eye image Rv and the left-eye image Lv. Therefore, even when the angle of view of the images obtained by these imaging units is shifted due to the parallax between the two imaging units, the focus adjustment for obtaining a clear stereoscopic image is Corresponding to the imaging unit It is possible to accurately easily with two optical systems.

  In the first embodiment, the AF evaluation value is calculated using the luminance value of each pixel constituting the image in the AF evaluation area. However, the AF evaluation value is calculated for each pixel constituting the image in the AF evaluation area. Instead of the luminance value, the luminance difference between adjacent pixels in the image in the AF evaluation area may be used for calculation.

  In the first embodiment, the AF evaluation area for acquiring the image data used for focusing the optical system of the first imaging unit is always set at the center of the right-eye image obtained by the first imaging unit. Although shown, the AF evaluation area may be set at an arbitrary position in the right-eye image by the operation of the operator.

  In this case, when the AF evaluation region setting unit 32e shown in FIG. 6 receives a command signal for instructing movement of the AF setting region by the operator as the operation signal Sop, the first luminance value generation unit 32c As shown in FIG. 8A, the first luminance value generation is performed so that the initial setting area Raf for reading image data used for automatic focusing from the first frame memory 32a is replaced with a command area Raf1 instructed by the operator. It is desirable that the part 32c be controlled.

  Also, the replacement instruction of the AF setting area by the operator may be performed by selecting from a plurality of areas set in advance on the display screen V of the monitor unit 40 of the compound eye imaging apparatus.

  For example, as shown in FIG. 8B, the monitor unit 40 shown in FIG. 2 is arranged so as to overlap with a display screen that displays an image, and is divided into a plurality of partitioned regions Vr1 to Vr9. A pair of parallax images obtained by imaging a subject are displayed on a display screen so that a stereoscopic image is recognized, and an AF evaluation area setting unit 32e is provided on the display screen. An area corresponding to a partitioned area (for example, the central partitioned area Vr5) designated by the operator's touch operation among the partitioned areas may be set as the first focus evaluation area Raf1.

  In the above description, the case where the relative position between the AF evaluation area and the left-eye image is matched with the relative position between the AF evaluation area and the right-eye image has been described, but this may be reversed, that is, the AF evaluation area and the right-eye image. The relative position with the image for use may be matched with the relative position between the AF evaluation area and the image for the left eye.

Further, although not specifically described in the first embodiment, a digital camera such as a digital video camera or a digital still camera, an image input camera, a scanner, or the like using the compound eye imaging device of the first embodiment as an imaging unit. An electronic information device having an image input device such as a facsimile or a camera-equipped cellular phone will be briefly described below.
(Embodiment 2)
FIG. 9 is a block diagram illustrating a schematic configuration example of an electronic information device using the solid-state imaging device of Embodiment 1 as an imaging unit as Embodiment 2 of the present invention.

  An electronic information device 90 according to Embodiment 2 of the present invention illustrated in FIG. 9 includes the compound-eye imaging device according to Embodiment 1 of the present invention as an imaging unit 91 that captures a subject, and such an imaging unit. Memory unit 92 such as a recording medium for recording data after high-definition image data obtained by photographing with a predetermined signal processing for recording, and a liquid crystal display screen after a predetermined signal processing for display of this image data A display unit 93 such as a liquid crystal display device that displays on the display screen, a communication unit 94 such as a transmission / reception device that performs communication processing after the image data is subjected to predetermined signal processing for communication, and prints (prints) the image data. And an image output unit 95 that outputs (prints out).

  As mentioned above, although this invention has been illustrated using preferable embodiment of this invention, this invention should not be limited and limited to this embodiment. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  In the fields of a compound-eye imaging device, a focusing method for a compound-eye imaging device, and an electronic information device, the focus of an optical system for capturing each of a pair of left and right parallax images with different angles of view is easily set to an appropriate position The compound eye imaging device capable of acquiring a pair of left and right parallax images for obtaining a clear stereoscopic image while suppressing the control time required for automatic focusing in a short time, and the focus of the compound eye imaging device A matching method and an electronic information device using such a compound eye imaging device can be realized.

11 1st optical system 12 1st image pick-up part (right image pick-up element)
13 First AF integration unit 14 First lens position calculation unit 15 First actuator driving unit 16 First actuator 21 Second optical system 22 Second imaging unit (left imaging element)
23 Second AF integration unit 24 Second lens position calculation unit 25 Second actuator driving unit 26 Second actuator 31 Signal processing unit 32 Digital signal processing circuit 32a First frame memory 32b Second frame memory 32c Second 1 luminance value generation unit 32d second luminance value generation unit 40 monitor unit 100 compound-eye imaging device 101 device housing 102 operation button Ad1, Ad2 drive signal Daf1 first AF evaluation value Daf2 second AF evaluation value Dv1, Dv2 Image data Ep Movement end point H Human image La Imaging region (field of view of second imaging unit)
Laf Second focus evaluation area Lv Left eye image (the other parallax image)
Ra imaging area (field of view of first imaging unit)
Raf First focus evaluation region Rd1, Rd2 Luminance value Rv Right eye image (one parallax image)
Sop operation signal Sp Movement start point T Subject

Claims (12)

A compound eye imaging device that obtains a pair of parallax images forming a stereoscopic image of a subject by photographing the subject,
A first imaging unit that images the subject so that one of the pair of parallax images is obtained;
A second imaging unit that images the subject so that the other of the pair of parallax images is obtained;
A first optical system for introducing light from the subject into a first imaging unit;
A second optical system for introducing light from the subject into a second imaging unit;
The focus of the first optical system is determined based on the image in the first focus evaluation region in the one parallax image, and the focus of the second optical system is determined as the second focus evaluation in the other parallax image. A focus determining unit that determines based on an image in the region,
The focus determination unit is configured such that a relative position of the second focus evaluation region with respect to the other parallax image is relative to the one parallax image based on parallax between the first imaging unit and the second imaging unit. A compound-eye imaging apparatus that adjusts the relative position of the second focus evaluation region with respect to the other parallax image so as to coincide with the relative position of the first focus evaluation region. The compound eye imaging device according to claim 1,
The focus determination unit
A relative position of the first focus evaluation area with respect to the one parallax image is determined based on an operation signal of the operator, and a relative position of the second focus evaluation area with respect to the other parallax image is determined based on the one parallax. A compound eye imaging apparatus having an evaluation area setting unit for matching the relative position of the first focus evaluation area with respect to an image. The compound eye imaging apparatus according to claim 2,
The evaluation area setting unit includes:
A compound-eye imaging device configured to set the first focus evaluation region at an arbitrary position on the one parallax image based on an operation signal of the operator. In the compound eye imaging device according to claim 1 or 2,
A display screen for displaying an image, and a touch panel arranged on the display screen and divided into a plurality of partitioned areas, and the pair of parallax images obtained by imaging the subject A monitor unit for displaying on the display screen so that a stereoscopic image is recognized;
The evaluation area setting unit selects an area corresponding to a partition area designated by a touch operation of the operator among the plurality of partition areas in one of the pair of parallax images displayed on the display screen. A compound eye imaging device configured to be set as one focus evaluation region. The compound eye imaging device according to claim 1,
The focus determination unit
A compound-eye imaging device configured to set the first focus evaluation region at the center of the one parallax image. In the compound eye imaging device according to any one of claims 1 to 5,
The focus determination unit
A first evaluation value calculation unit for calculating a first focus evaluation value for evaluating the degree to which the first optical system is in focus with respect to the image in the first focus evaluation region;
A first focus position calculation unit that calculates a focus position in the first optical system based on the first focus evaluation value;
A second evaluation value calculation unit that calculates a second focus evaluation value for evaluating the degree to which the second optical system is in focus with respect to the image in the second focus evaluation region;
A compound eye imaging apparatus comprising: a second focus position calculation unit that calculates a focus position in the second optical system based on the second focus evaluation value. The compound eye imaging device according to claim 6,
The first focus evaluation value is a value obtained by integrating the luminance value of each pixel constituting the image in the first focus evaluation area over the entire first focus evaluation area,
The second focus evaluation value is a compound eye image obtained by integrating the luminance value of each pixel constituting the image in the second focus evaluation area over the entire second focus evaluation area. apparatus. The compound eye imaging device according to claim 6,
The first focus evaluation value is a value obtained by integrating the luminance difference between adjacent pixels in the image in the first focus evaluation area over the entire first focus evaluation area,
The second focus evaluation value is a value obtained by integrating the luminance difference between adjacent pixels in the image in the second focus evaluation area over the entire second focus evaluation area. apparatus. In the compound eye imaging device according to any one of claims 1 to 8,
The optical axis of the first optical system and the optical axis of the second optical system are parallel,
The compound-eye imaging device, wherein the parallax between the first imaging unit and the second imaging unit is a separation distance between the optical axis of the first optical system and the optical axis of the second optical system. The compound eye imaging device according to claim 9,
The first optical system includes a first focus lens, and a focal position of the first optical system is adjusted by movement of the first focus lens on the optical axis of the first optical system. It is configured as
The second optical system includes a second focus lens, and a focal position of the second optical system is adjusted by movement of the second focus lens on the optical axis of the second optical system. A compound eye imaging device configured as described above. A method for focusing a compound-eye imaging device in which one of a pair of parallax images forming a stereoscopic image of a subject is captured by a first imaging unit and the other of the pair of parallax images is captured by a second imaging unit. ,
The focus of the first optical system that introduces the light of the subject into the first imaging unit is determined based on the image in the first focus evaluation area in the one parallax image, and the second imaging unit Determining a focus of a second optical system for introducing light from the subject based on an image in a second focus evaluation region in the other parallax image;
In this step, based on the parallax between the first imaging unit and the second imaging unit, the relative position of the second focus evaluation region with respect to the other parallax image is the first position with respect to the one parallax image. A focusing method for a compound-eye imaging apparatus, wherein the relative position of the second focus evaluation area with respect to the other parallax image is adjusted so as to coincide with the relative position of one focus evaluation area. An electronic information device including an imaging unit,
An electronic information device using the compound-eye imaging device according to any one of claims 1 to 10 as the imaging unit.

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