JP2013254089A - Display device, display method and imaging device including display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately present information captured by a light-field camera having two or more angle divisions to a user.SOLUTION: A display device for displaying pixel signals obtained by performing photoelectric conversion of a subject image with an imaging element on display means is configured to comprise: signal acquisition means that acquires information including pixel signals obtained by the light-field camera; display area division means that divides a display screen of the display means into a plurality of division display areas; base-line direction control means that sets a base-line length direction to be used in range-finding; and display control means that displays the pixel signal corresponding to different pupil areas but not adjacent to each other of two or more pupil areas divided in the base-line length direction set by the base-line direction control means on the basis of the information obtained by the signal acquisition means in one of the plurality of division display areas.

Description

  The present invention relates to a display device used in an imaging apparatus typified by a digital camera, and more particularly to a display method of a pixel signal acquired by a camera capable of acquiring light space information (also referred to as a light field).

  In recent years, digital cameras have been improved in functionality, and a camera capable of acquiring light space information has been proposed as a new camera form. Such a camera is commonly called a light field camera or the like. Light field cameras can provide functions such as changing the focus position after shooting by acquiring pixel signals from light fluxes that have passed through different pupil regions and reconstructing images from the acquired pixel signals to obtain output images. Is possible.

  On the other hand, the light field camera needs to present the acquired information to the user as appropriate.

  In order to solve this problem, Patent Document 1 discloses a technique for displaying a so-called split image by displaying images that have passed through different pupil regions in different regions.

  Further, Patent Document 2 discloses a technique for displaying an image that has passed through different pupil regions in an imaging optical system provided with a focus detection element.

JP 2009-232288 A JP 2008-116848 A

  However, in the related art disclosed in the above-mentioned patent document, when the pupil region is divided into a larger number (when the number of angle divisions in the light field camera is larger than 2), the display may not be appropriately performed. .

  That is, Patent Document 1 and Patent Document 2 disclose information about a case where an image that has passed through different pupil regions for focus detection is basically divided into two. On the other hand, a preferred display method in the case of having more divisions is not disclosed.

  Accordingly, an object of the present invention is to provide a display device capable of appropriately presenting to a user an image that has passed through different pupil regions, using information acquired by a light field camera having more than two angle divisions. An object of the present invention is to provide a photographing apparatus provided with a display device.

  According to the present invention, a display device for displaying on a display means a pixel signal obtained by photoelectrically converting a subject image by an image sensor acquires a signal for acquiring information including the pixel signal obtained by a light field camera. Means, a display area dividing means for dividing the display screen of the display means into a plurality of divided display areas, a baseline direction control means for setting a baseline length direction used for ranging, and the signal acquisition means in one area of the plurality of divided display areas Display control for displaying the pixel signals corresponding to different non-adjacent pupil regions out of more than two pupil regions divided in the baseline length direction set by the baseline direction control means based on the information acquired in Means.

  According to the invention, the imaging device includes the display device of the invention.

  ADVANTAGE OF THE INVENTION According to this invention, the imaging device provided with the display apparatus which can show suitably the information acquired with the light field camera which has more than two angle divisions to a user, and the said display apparatus can be provided. .

1 is a block diagram of an imaging apparatus to which the present invention is applied in an embodiment. The figure which shows typically the imaging optical system of the imaging device of FIG. FIG. 2 is a diagram conceptually illustrating an image generation operation in the imaging apparatus of FIG. 1. FIG. 3 is a diagram illustrating a flowchart of the operation of the imaging apparatus in FIG. 1. The figure which shows the display structure by the display apparatus concerning the 1st Example of this invention. The figure which shows typically the setting of the base line length direction in the display apparatus concerning the 1st grade of this invention. The figure which shows the display structure of the display apparatus concerning the 2nd Example of this invention. FIG. 6 is a diagram illustrating another example of an imaging optical system of an imaging apparatus to which the present invention is applied.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic diagram for explaining a main part of the present invention.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. The display device of the present invention is used for aiming prior to photographing and image display at the time of development after photographing. In the present embodiment, a case where the present invention is applied to an imaging device will be described as an example. .

  FIG. 1 is a block diagram of a camera system which is a photographing apparatus according to an embodiment of the present invention. This camera system includes a camera 1 and a lens 2 and includes an imaging system, an image processing system, a recording / reproducing system, and a control system. The imaging system includes an imaging optical system 3 and an imaging element 6, and the image processing system includes an image processing unit 7. The recording / reproducing system includes a memory unit 8 and a display unit 9, and the control system includes a camera system control circuit 5, an operation detection unit 10, a lens system control circuit 12, and a lens driving unit 13. The lens driving unit 13 can drive a focus lens, a shake correction lens, a diaphragm, and the like.

  The imaging system is an optical processing system that forms an image of light from an object on the imaging surface of the imaging device 6 via the imaging optical system 3. The imaging element 6 has a light receiving surface in which pixels (photoelectric conversion elements) are two-dimensionally arranged, and microlenses are arranged in a lattice pattern on the light receiving surface to form a so-called microlens array (hereinafter referred to as MLA). ing. The MLA constitutes pupil dividing means in this embodiment. Details of the functions and arrangement of the MLA will be described later with reference to FIG. As will be described later, since the focus evaluation amount / appropriate exposure amount is obtained from the pixel signal output from the image sensor 6, the photographing optical system 3 is appropriately adjusted based on this amount. Thereby, subject light of an appropriate amount of light is exposed to the image sensor 6 and a subject image is formed in the vicinity of the image sensor 6.

  The image processing unit 7 includes an A / D converter, a white balance circuit, a gamma correction circuit, an interpolation calculation circuit, and the like, and can generate a recording image. In addition, an image shift unit, an image generation unit, a contrast evaluation unit, a correlation calculation unit, and the like, which are main parts of the present invention, can be included. (In this embodiment, these elements are described assuming that they are arranged in the camera system control.)

  The memory means 8 includes a processing circuit necessary for recording in addition to an actual storage unit. The memory means outputs to the recording unit and generates and stores an image to be output to the display means 9. Further, the memory means 8 compresses the amount of information such as images, moving images, and sounds using a predetermined method.

  The camera system control circuit 5 generates and outputs a timing signal at the time of imaging. The imaging system, image processing system, and recording / reproducing system are controlled in response to external operations. For example, the operation detection circuit 10 detects that a shutter release button (not shown) is pressed, and controls driving of the image sensor 6, operation of the image processing unit 7, compression processing of the memory unit 8, and the like. Further, the state of each segment of the information display device that displays information on a display screen such as a liquid crystal monitor is controlled by the display means 9.

  The adjustment operation of the optical system by the control system will be described. An image processing unit 7 is connected to the camera system control circuit 5, and appropriate focus positions and aperture positions are obtained based on pixel signals (photoelectric conversion signals) from the image sensor 6. The camera system control circuit 5 issues a command to the lens system control circuit 12 via the electrical contact 11, and the lens system control circuit 12 appropriately controls the lens driving means 13. Further, a camera shake detection sensor (not shown) is connected to the lens system control circuit 12. In the camera shake correction mode, the shake correction lens is appropriately controlled via the lens driving means 13 based on the signal of the camera shake detection sensor. To do.

  FIG. 2 is a diagram schematically showing a configuration of a main part of the photographing optical system in the present embodiment. In order to apply the present invention, it is necessary to acquire angle information in addition to the position of light rays, so-called light space information. In this embodiment, in order to obtain angle information, an MLA is arranged in the vicinity of the imaging plane of the photographing optical system 3, and a plurality of pixels are associated with one lens constituting the MLA.

  FIG. 2A is a diagram schematically illustrating the relationship between the image sensor 6 and the MLA 20. FIG. 2B is a schematic diagram showing the correspondence between the pixels of the image sensor and the MLA. FIG. 2C is a diagram showing that pixels provided under the MLA by the MLA are associated with a specific pupil region.

  As shown in FIG. 2A, the MLA 20 is provided on the image sensor 6, and the front principal point of the MLA 20 is arranged in the vicinity of the imaging plane of the photographing optical system 3. FIG. 2A shows a front view and a side view when the image pickup device 6 is viewed from the side and the front of the image pickup apparatus. As can be seen from the front view, the MLA lens is a pixel on the image pickup device 6. It is arranged to cover. In FIG. 2A, the microlenses constituting the MLA are illustrated in large size so that the microlenses are easy to see, but each microlens is actually only about several times as large as a pixel. (The actual size will be described with reference to FIG. 2B.)

  FIG. 2B is a partially enlarged view of the front view of FIG. A grid-like frame shown in FIG. 2B indicates each pixel of the image sensor 6. On the other hand, each microlens constituting the MLA is indicated by thick circles 20a, 20b, 20c, and 20d. As apparent from FIG. 2B, a plurality (a predetermined number) of pixels are assigned to one microlens. In the example of FIG. 2B, 5 rows × 5 columns = 25 pixels are 1 It is provided for two microlenses. (That is, the size of each microlens is 5 × 5 times the size of the pixel.)

  FIG. 2C is a diagram in which the image sensor 6 is cut so that the longitudinal direction of the sensor includes the microlens optical axis and is in the horizontal direction of the drawing. 2, 21, 22, 23, 24, and 25 in FIG. 2C indicate pixels (one photoelectric conversion unit) of the image sensor 6. On the other hand, the figure shown above FIG. 2C shows the exit pupil plane of the photographing optical system 3. Actually, when the direction is aligned with the sensor diagram shown in the lower part of FIG. 2C, the exit pupil plane is in the direction perpendicular to the plane of FIG. 2C, but the projection direction is changed for the sake of explanation. Yes. In FIG. 2C, one-dimensional projection / signal processing will be described to simplify the description. In an actual device, this can be easily extended to two dimensions.

  The pixels 21, 22, 23, 24, and 25 in FIG. 2C are in a positional relationship corresponding to 21a, 22a, 23a, 24a, and 25a in FIG. As shown in FIG. 2C, each pixel is designed to be conjugate with a specific area on the exit pupil plane of the photographing optical system 3 by the microlens 20. In the example of FIG. 2C, the pixel 21 and the region 27a correspond to the pixel 22 and the region 27b, the pixel 23 and the region 27c, the pixel 24 and the region 27d, and the pixel 25 and the region 27e, respectively. That is, only the light beam that has passed through the region 27 a on the exit pupil plane of the photographing optical system 3 enters the pixel 21. The same applies to the other pixels. As a result, it is possible to obtain angle information from the passing area on the pupil plane and the positional relationship on the image sensor 6.

  FIG. 3 schematically shows image shift and image generation. FIG. 3 is lined up with (a), (b), and (c) from above, and FIG. 3 (b) shows image generation on the surface where the image pickup device 6 actually exists and the image is acquired. 3A shows image reconstruction on a reconstruction surface (reconstruction surface 1) closer to the subject side than FIG. 3B, and FIG. 3C shows the subject reconstruction side from FIG. 3B. Image reconstruction is shown on the far-side reconstruction plane (referred to as reconstruction plane 2).

In FIG. 3B, X _{1, i} , X _{2, i} , X _{3, i} , X _{4, i} , X _{5, i} pass through the pupil regions 1, _{2, 3, 4, 5} respectively and are microscopic. Data obtained by entering the lens X _i is shown. That is, of the subscripts, the first half indicates the passing pupil region, and the second half indicates the pixel number. Also, in FIG. 3, the data is described as having only one-dimensional expansion for the sake of clarity. In relation to the physical position, X _{1, i} indicates data obtained from the 21 region in FIG. 2C, X _{2, i} indicates data obtained from the 22 region in FIG. The other X subscripts 3, 4, and 5 indicate that they correspond to the regions 23, 24, and 25, respectively.

In order to generate an image on the acquisition surface, data incident on the microlens X _i may be added as shown in FIG. Specifically, the integrated value in the angular direction of the light incident on X _i can be obtained with S _i = X _{1, i} + X _{2, i} + X _{3, i} + X _{4, i} + X _{5, i} . (This produces an image similar to a normal camera.)

Next, a method for generating an image on the reconstruction plane 1 will be considered. As described with reference to FIG. 2, the imaging optical system of the present embodiment limits the luminous flux incident on each pixel to a specific pupil region, so the incident angle is known. The position of each pixel on the reconstruction plane is reconstructed along this angle. Specifically, it is assumed that a pupil region with a subscript of 1 such as X1 _{, i} is incident at an angle as shown at 41 on the right side of FIG. Hereinafter, it is assumed that the subscripts 2, 3, 4, and 5 of the pupil region correspond to 32, 33, 34, and 35, respectively. At this time, the light beam incident on the microlens X _i on the reconstruction surface 1 is scattered and incident on the acquisition surface from X _{i −2} to X _{i + 2} . More specifically, it is distributed in X1 _{, i-2} , X2 _{, i-1} , X3 _{, i} , X4 _{, i + 1} , and X5 _{, i + 2} . To restore the image in the reconstruction plane 1 is not limited to the X _i is the image it can be seen that may be added by shifting the in accordance with the incident angle. In order to generate an image on the reconstruction plane 1, a shift corresponding to the incident angle can be given as follows. A pupil area subscript 1 shifts 2 pixels to the right, a pupil area subscript 2 shifts right by 1 pixel, a pupil area subscript 3 shifts no, pupil area subscript 4 is shifted to the left by 1 pixel, and the pupil area subscript 5 is shifted to the left by 2 pixels. Thereafter, the data in the reconstruction plane 1 can be obtained by adding in the vertical direction of FIG. Specifically, in _{S i = X 1, i-} 2 + X 2, i-1 + X 3, i + X 4, i + 1 + X 5, i + 2 in the reconstruction plane 1, the X _i An integral value in the angular direction of the incident light can be obtained. As a result, an image on the reconstruction surface was obtained.

Here, in the reconstruction plane 1, if you had bright spots X _i, the acquisition plane _{X 1, i-2, X} 2, i-1, X 3, i, X 4, i + 1, X _{It is} in a so-called blurred state dispersed in _{5, i + 2} . However, when the image on the reconstruction plane 1 described above is generated, a bright spot is generated again on X _i and an image with high contrast is obtained. That is, so-called contrast AF can be performed by reconstructing the image and calculating the contrast.

  Further, as can be seen from FIG. 3C, an image can be generated on the reconstruction plane 2 in the same manner as the reconstruction plane 1. If the direction in which the reconstruction plane is arranged is different (meaning opposite to the object), it is only necessary to reverse the direction of shifting.

  FIG. 4 is a flowchart for obtaining an image of the present invention. 4A shows the overall operation of obtaining an image, FIG. 4B shows the operation of the image shift means, FIG. 4C shows the operation of the image generation means, and FIG. 4D shows the operation of the correlation calculation means. Respectively. These operations are realized, for example, by controlling each unit of the imaging apparatus by loading and executing a program stored in a memory (not shown) by the CPU of the camera system control circuit 5.

  A description will be given in order of each step from FIG. Step S1 indicates the start of the image acquisition operation. For example, this is the case when the operation detection unit 10 shown in FIG. 1 detects a specific operation from the photographer (for example, pressing the release button).

  Step S411 corresponds to acquiring data by exposing the image sensor 6 for an appropriate time and reading out (A / D conversion) the obtained pixel signal.

  In step S412, the correlation calculation means is operated to obtain a result. Information relating to the focus evaluation value is obtained from the correlation calculation means. Details of the operation will be described later with reference to FIG.

  In step S413, a focus position is determined for each appropriately divided area (which will be described later in the description of the correlation calculation means, but corresponds to the evaluation frame in step S462). The position where the focus evaluation value obtained from the correlation calculation means described later is the best is defined as the focus position. (Here, “good” corresponds to a state where a small value is good according to a correlation calculation formula in step S466 described later.)

  However, the focus position here indicates a relative focus shift from the current focus position. That is, the focus position of the subject that is in focus at the current focus position is set to 0, and the subjects that are in front or behind it are obtained as values having plus or minus signs. Furthermore, the focus position is obtained as indicating the position of the image plane on the image plane side, not the depth on the subject side.

  In step S414, the image shift means is operated to obtain a result. There are several methods for specifying the image generation position at this time. For example, a method of giving a focus position by combining the focus position of each area obtained in step S413 and the subject recognition result can be considered. In this way, it is possible to focus on an object recognized as a subject. Alternatively, a user-specified position can be given. In this way, so-called manual focus can be realized. Details of the operation of the image shift means will be described later with reference to FIG.

  In step S415, the image generating means is operated to obtain a result. Details of the operation of the image generating means will be described later with reference to FIG.

  In step S416, necessary processing such as conversion to a recording image format and compression is performed, and then recording is performed in the memory unit 8.

  In step S8, the series of operations from image acquisition to recording ends.

  Details of the operation of the image shift means will be described with reference to FIG. Step S421 indicates the start of the operation of the image shift means.

  Steps S422 to S427 form a loop. In step S422, loop calculation is executed by the number corresponding to the number of pupil divisions. For example, in the example shown in FIG. 2, since it is divided into 25, calculation according to each pupil position of 25 is performed. As described with reference to FIG. 3, considering the reconstruction of the image, if the incident angle is different even on the same reconstruction surface (if the exit pupil is sufficiently far away, it is almost synonymous with the difference in the passing pupil region. ) The amount of image shift is different. This is a loop for appropriately reflecting this.

  In step S423, the incident angle is determined based on the data from step S424. That is, as described with reference to FIG. 2, since the incident angle is determined by the physical configuration, the information is read and the incident angle corresponding to each pupil region is calculated.

  In step S425, the shift amount is calculated from the incident angle determined in step S424 and the position of the reconstruction surface. This corresponds to the fact that when the position and the incident angle of the reconstruction surface are determined as in the reconstruction surface 1 and the reconstruction surface 2 in FIG. 34, the pixels are shifted laterally accordingly.

  In step S426, image shift is executed according to the amount obtained in step S425.

  In step S428, the process returns to step S413 and step S477 of the caller.

  Details of the operation of the image generating means will be described with reference to FIG. Step S431 indicates the start of the operation of the image generating means.

In step S432, the area data for addition in step S435 is initialized (filled with 0). The size of the data area at this time may be the number of MLA, and the gradation of data is convenient as long as the product of the gradation of the original data and the number of pupil divisions can be stored. For example, if the original data is 8 bits and divided into 25, if 13 bits (> 8 bits + log ₂ 25), there is no need to consider data overflow.

  Steps S433 to S438 form a loop. In step S433, loop calculation is executed according to the number of microlenses constituting the MLA. For example, in the example illustrated in FIG. 23, the number of microlens is the number of pixels of the original image sensor ÷ 25 (number of pupil divisions).

  Steps S434 to S437 form a loop. In step S434, the loop calculation is executed by the number corresponding to the number of pupil divisions. For example, in the example shown in FIG. 2, since the light is divided into 25, the light fluxes from the 25 pupil positions are processed.

  In step S435, it is determined whether the pupil region should be added. In other words, an image according to the intention is provided by changing a region to be added according to a user setting. In general, when the number of pupil regions to be added is increased, an image having excellent S / N and a shallow depth of focus is obtained.

  In step S436, addition is performed. If the shift amount is not an integral multiple of the pixel, the addition is performed while being appropriately divided in addition S436. (It may be added appropriately according to the overlapping area.)

  In step S439, the process returns to caller step S416.

  Details of the operation of the correlation calculation means will be described with reference to FIG. Step S461 indicates the start of the operation of the correlation calculation means.

  In step S462, the number of evaluation points to be evaluated and the size of the evaluation frame are set. The evaluation frame here is preferably as small as possible within a range where the correlation can be appropriately calculated without losing the noise. By doing so, focus position detection is appropriately performed when defect correction is performed.

  Steps S463 to S469 form a loop. In step S463, the calculation is repeated so as to obtain an evaluation value corresponding to the evaluation number determined in step S462.

  Steps S464 to S467 form a loop. In step S464, correlation calculation is performed in the range of the number of pixels corresponding to the size of the evaluation frame determined in step S462.

In step S465, it is determined whether A _i or B _i is defective. If it is a defect, it is not appropriate to use it for correlation calculation, so the process proceeds to step S467. If it is not a defect, the process proceeds to step S466. For example, the correlation calculation may be performed by Σ | A _i −B _i | as in step S466. Here, A _i indicates the luminance of the i-th pixel that has passed through a specific pupil region. B _i indicates the luminance of the i-th pixel that has passed through a pupil area different from A _i . For example, in FIG. 2, A _i may be a line in which only pixels corresponding to the pixel 22 are arranged, and B _i may be a line in which only pixels corresponding to the pixel 24 are arranged. Which pixel of the pupil region to select may be determined according to the length of the base line length, the vignetting situation of the pupil surface, and the like.

  By setting as described above, the correlation between images that have passed through different pupil regions can be calculated, and an evaluation amount based on so-called phase difference AF can be obtained. In step S68, the obtained correlation value is stored as an evaluation amount.

In the evaluation formula Σ | A _i −B _i | shown above, the part where the correlation value is small corresponds to the part where the focus state is the best. Here, the correlation calculation is performed by the method of adding the difference absolute value, but the correlation calculation is performed by other calculation methods such as the method of adding the maximum value, the method of adding the minimum value, the method of adding the square difference value, and the like. Also good.

  In step S469, the process returns to caller step S416.

The configuration of display control according to the present embodiment will be described with reference to FIG. This display control is performed using imaging information including pixel signals obtained by the above-described light field camera (signal acquisition means).
In FIG. 5A, 9a is a monitor constituting the display device, 52 and 53 in FIG. Each of the display areas is shown.

  When photographing using the photographing apparatus which is the subject of the present invention, the photographer determines the composition while looking at the monitor 9a provided on the back of the photographing apparatus. Further, in the present invention, a point to be focused (this is defined as a distance measuring point) is indicated. In the example of FIG. 5A, a touched part is defined as a distance measuring point by touching a flower as a subject. The distance measuring point may be indicated by other methods (such as a method using a cross key provided separately). In this way, it is possible to set the distance measuring point according to the user's instruction, and it operates as a distance measuring area control means.

  The display device 9 according to the present embodiment divides the vicinity of the distance measuring point into three areas of two areas 52 and 53 and another area 51 (display area dividing means). The dividing direction of the areas 52 and 53 is preferably set to the base line length direction in which distance measurement is performed (the direction in which image shift is desired). In the example of FIG. 5, it is assumed that the baseline length direction is defined (set) in advance in the horizontal direction. That is, a case where the baseline direction control means holds a value defined in the horizontal direction will be described. A method of instructing the baseline length by the baseline direction control means will be described later.

  The display control means (in this embodiment, the circuit in the camera system control 5 plays its role) instructs the display means 9 to display different pupil area signals for each divided area. In the example of FIG. 5B, images (pixel signals) obtained from the areas 27e and 27a are displayed in the divided display areas 52 and 53 provided near the distance measuring points, respectively. On the other hand, an image obtained by adding pixel signals obtained from all pupil regions is displayed in the other region 51. (In the example of FIG. 5B, this corresponds to adding pixel signals from 27a to 27e. Actually, it has a two-dimensional spread, but only the one-dimensional direction will be described here.) By so doing, so-called split image display becomes possible. Although not shown here, if the above configuration is used as it is, the regions 52 and 53 are dark because there is no addition, and the region 51 is displayed brightly. This can be adjusted by appropriately controlling the gain.

  FIG. 5C to FIG. 5E schematically show the display of the divided display area when the focus state is changed in this state. The focus state changes in the order of FIG. 5 (c) → FIG. 5 (d) → FIG. 5 (e), and FIG. 5 (d) is a state in focus. In the focused state, the same image can be obtained regardless of the pupil region that passes through, so that the images of the region 52 and the region 53 are matched without being shifted. On the other hand, when the focus state changes, an image shift occurs in the baseline length direction due to the passing pupil region as shown in FIG. 5C and FIG. By observing this, it is possible to intuitively grasp whether or not the current optical state is in focus on the subject.

  As a preferred method for selecting the display area, it is only necessary to select pupil areas separated in the baseline length direction. Further, it is preferable to select a pupil region as far as possible (not adjacent) in a range where vignetting does not occur in consideration of the F number of the optical system. Furthermore, in order to reduce the blur when the split image is laterally shifted, as shown in the example of FIG. 5B, the image displayed in the divided display area provided near the distance measuring point is displayed without being added. Is preferred. Specifically, in FIG. 5B, the region 27a and the region 27e are used, but the base line length is longer than when the regions 27b, 27c, and 27d are used. The lines are larger and focus adjustment is easier. Furthermore, it is possible to form a split image by adding the areas 27c, 27d, and 27e to the area 52 and adding the areas 27a, 27b, and 27c to the area 53. The blur will become larger. For this reason, when the area 27a and the area 27e are used, even when the focus fluctuates, the blur generated in the image is small and the focus adjustment is easy.

  FIG. 6 is a diagram for explaining a method of setting the baseline length. In the present invention, it is necessary to display pupil regions separated in the baseline length direction, but the case where the baseline length direction is set in the display configuration of FIG. 5 has been described. In the present embodiment, a configuration set through the monitor 9a (touch panel) will be described with reference to FIG. However, the present invention is not limited to this. For example, the setting may be made using an operation member provided in the imaging apparatus.

  FIG. 6A shows a configuration in which the base line length is set in the horizontal direction, and FIG. 6B shows a region division when the base line length is set in the horizontal direction and a pupil region displayed there. FIG. 6 (c) shows a configuration in which the base line length is set in the vertical direction, and FIG. 6 (d) shows a region division when the base line length is set in the vertical direction and a pupil region displayed there.

  In FIG. 6A, the monitor 9a is a so-called touch panel, and is configured to detect the touch position and the moving direction. In order to indicate the distance measuring point and the baseline length direction in FIG. 6A, first, a point on the main subject (defined as the distance measuring point) is touched, and then the finger is slid in the baseline length direction. Thus, the slide direction is defined (set) as the baseline length direction. FIG. 6A illustrates a state in which the subject is touched, and an arrow in the figure indicates the subsequent sliding direction of the finger. In FIG. 6A, since the finger is slid in the horizontal direction (horizontal direction), the baseline length is defined in the horizontal direction. By this operation, the area in the vicinity of the distance measuring point is divided as indicated by 52 and 53 in FIG. That is, the split display area is formed so that two areas are arranged so as to be orthogonal to the set base line length direction (in FIG. 6B, there are two areas 52 and 53 in the vertical (vertical direction)). Is set. Moreover, what is necessary is just to select the area | region separated in the base line length direction as the pupil area | region displayed on the area | regions 52 and 53. FIG. In the example of FIG. 6B, the pupil region 62a is associated with the region 52, and the pupil region 63a is associated with the region 53. As shown in the example of FIG. 5, the other areas 51 are added and displayed including the other pupil areas.

  In FIG. 6C, since the finger is slid in the vertical direction (vertical direction), the base line length is defined (set) in the vertical direction. By this operation, the area in the vicinity of the distance measuring point is divided as indicated by 52 and 53 in FIG. That is, the areas are set so that the two areas are arranged so as to be orthogonal to the set baseline length direction (in FIG. 6D, there are two areas 52 and 53 in the horizontal direction). At this time, the pupil regions displayed in the regions 52 and 53 may be selected as regions separated in the baseline length direction, so in the example of FIG. 6B, the pupil region 62b corresponds to the region 52 and the pupil region 63b corresponds to the region 53. I am letting. As shown in the example of FIG. 5, the other areas 51 are added and displayed including the other pupil areas.

  By controlling the display area and the pupil area displayed there as described above, it is possible to make a display that is sensitive to a focus shift and is easy to see with little blur even when a focus shift occurs. In other words, the display configuration described with reference to FIG. 5 makes it possible to perform convenient display when performing manual focus on two or more pupil division regions.

  Next, a second embodiment of the display device of the present invention will be described with reference to FIG. The present embodiment is an example in which the present invention is applied to the image pickup apparatus of FIG. 1 as in the first embodiment, but the image display configuration in the divided display area is different from that of the first embodiment. Accordingly, the configuration of the imaging apparatus and its imaging optical system is as described with reference to FIGS. 1 to 4, and a description thereof is omitted here. Further, the definition (setting) of the distance measuring point and the setting in the baseline length direction are the same as those in FIG. 7 that are the same as those in FIG. 5 are given the same reference numerals.

  FIG. 7 shows an example in which so-called double image matching is performed. In FIG. 7B, reference numeral 70 denotes a divided display area provided in the vicinity of the distance measuring point, and 51 denotes other display areas not included in the 70. As in the example of FIG. 5A, a distance measuring point is defined by touching the monitor 9 a and is divided into an area 70 and an area 51. In the example of FIG. 6 as well, the baseline length direction is defined (set) in the horizontal direction as in FIG.

  The display control means (in this embodiment, the circuit in the camera system control 5 plays its role) instructs the display means 9 to display different pupil area signals for each divided area. In the example of FIG. 7B, an image obtained by adding the pixel signals of the areas 27a and 27e is displayed in the divided display area 70 provided near the distance measuring point. On the other hand, an image obtained by adding the pixel signals of all pupil regions is displayed in the other region 51. In this way, so-called double image coincidence display is possible. In FIG. 7 (b), a gain of 1/2 is applied to the pixel signals in the areas 27a and 27e, but the present invention is not limited to this and can be set as appropriate.

  Changes in display when the focus state is changed in this state are schematically shown in FIGS. 7C to 7E. The focus state changes in the order of FIG. 7 (c) → FIG. 7 (d) → FIG. 7 (e), and FIG. 7 (d) is a state in focus. In the focused state, the same image can be obtained regardless of the pupil region that passes through, so the two images displayed in the region 54 match. On the other hand, when the focus state changes, an image shift occurs in the baseline length direction due to the passing pupil region as shown in FIGS. 7C and 7E, and two images appear. By observing this, it is possible to intuitively grasp whether or not the current optical state is in focus on the subject.

  Here, in order to observe the double image separately in two (recognized as an image shift rather than a blur), the pupil region after addition is limited to a narrow region with respect to the whole and separated from each other. It is desirable that

  In addition, when displaying a double image match, different color adjustments may be performed on the images of the two pupil regions before the addition is performed. For example, whether the focus is tied forward by adjusting the white balance so that the white balance is adjusted appropriately when matched with a blueish image and a yellowish image. Information about whether it is tied behind may be displayed.

  When the double image matching is used, the region division defines the region 70 in the vicinity of the distance measuring point as shown in FIG. 7, and the pupil region for generating an image to be displayed there is shown in FIG. It can be generated with reference to the example. That is, when the base line length is defined in the vertical direction, the pupil regions 62b and 63b in FIG.

  Also in the present embodiment, by controlling the display area and the pupil area displayed there, it is possible to make a display that is sensitive to a focus shift and is easy to see with little blur even when the focus shift occurs. . That is, by using the display configuration as described in FIG. 7, it is possible to perform a display that is convenient when manual focusing is performed on two or more pupil division regions.

  Here, another example of the optical system applicable to the present embodiment will be described with reference to FIG. FIG. 8 is a diagram schematically showing a state in which light rays from an object (subject) are imaged on the image sensor 6. FIG. 8A corresponds to the optical system described in FIG. 2, and is an example in which the MLA 20 is disposed in the vicinity of the imaging surface of the photographing optical system 3. FIG. 8B shows an example in which the MLA 20 is arranged closer to the object than the imaging plane of the photographing optical system 3. FIG. 8C shows an example in which the MLA 20 is arranged on the side farther from the object than the imaging plane of the photographing optical system 3. In the figure, the parts shown in the already described figures are denoted by the same reference numerals.

  In FIG. 8, 80 is an object plane, 80a and 80b are appropriate points on the object, 27 is a pupil plane of the photographing optical system, 81, 82, 83, 84, 85, 86, 87, 88 and 89 are Each specific microlens on the MLA is shown. In FIGS. 8B and 8C, 6a represents a virtual image sensor, and 20a represents a virtual MLA. These are shown for reference in order to clarify the correspondence with FIG. Also, a light beam that exits from the point 80a on the object and passes through the regions 27a and 27c on the pupil plane is indicated by a solid line, and a light beam that exits from the point 80b on the object and passes through the regions 27a and 27c on the pupil plane is indicated by a broken line. did.

  In the example of FIG. 8A, as described with reference to FIG. 2, the MLA 20 is disposed in the vicinity of the imaging plane of the photographing optical system 3, so that the imaging element 6 and the pupil plane 27 of the photographing optical system have a conjugate relationship. is there. Further, the object plane 80 and the MLA 20 are in a conjugate relationship. Therefore, the light beam emitted from the point 80a on the object reaches the microlens 81, the light beam emitted from the point 80b reaches the microlens 82, and the light beams that have passed through the regions 27a to 27e respectively correspond to those provided below the microlens. Reach the pixel.

  In the example of FIG. 8B, the light beam from the photographing optical system 3 is imaged by the microlens 20, and the imaging element 6 is provided on the imaging surface. By arranging in this way, the object plane 80 and the imaging device 6 are in a conjugate relationship. The light beam that has exited from the point 80a on the object and passed through the region 27a on the pupil plane reaches the micro lens 83, and the light beam that has exited from the point 80a on the object and passed through the region 27c on the pupil plane reaches the micro lens 84. To do. The light beam that has exited from the point 80b on the object and passed through the region 27a on the pupil plane reaches the microlens 84, and the light beam that has exited from the point 80b on the object and passed through the region 27c on the pupil plane reaches the microlens 85. To do. The light beam that has passed through each microlens reaches a corresponding pixel provided under the microlens. In this way, images are formed at different positions depending on the point on the object and the passing area on the pupil plane. If these are rearranged at positions on the virtual imaging surface 6a, the same information as in FIG. 8A can be obtained. That is, information on the pupil region (incident angle) that has passed through and the position on the imaging device can be obtained.

  In the example of FIG. 8C, the microlens 20 re-images the light beam from the photographing optical system 3 (this is called re-imaging because a light beam once formed is diffused). ), An image pickup device 6 is provided on the image plane. By arranging in this way, the object plane 80 and the imaging device 6 are in a conjugate relationship. The light beam that has exited from the point 80a on the object and passed through the region 27a on the pupil plane reaches the micro lens 87, and the light beam that has exited from the point 80a on the object and passed through the region 27c on the pupil plane reaches the micro lens 86. To do. The light beam that has exited from the point 80b on the object and passed through the region 27a on the pupil plane reaches the microlens 89, and the light beam that has exited from the point 80b on the object and passed through the region 27c on the pupil plane reaches the microlens 88. To do. The light beam that has passed through each microlens reaches a corresponding pixel provided under the microlens. Similar to FIG. 8B, information similar to that in FIG. 8A can be obtained by rearranging the positions on the virtual imaging surface 6a. That is, information on the pupil region (incident angle) that has passed through and the position on the imaging device can be obtained.

  FIG. 7 shows an example in which the position information and the angle information can be acquired by using the MLA (phase modulation element) as the pupil dividing means. However, the position information and the angle information (equivalent to restricting the passing area of the pupil) are shown. Other optical configurations can be used as long as they can be obtained. For example, a method of inserting a mask (gain modulation element) with an appropriate pattern into the optical path of the photographing optical system can be used.

  In the first and second embodiments, the method for carrying out the present invention using the monitor 9a provided in the photographing apparatus in the photographing preliminary operation in the imaging apparatus has been described, but also in the development after photographing. The present invention can be similarly applied. That is, an application for performing a so-called development operation for generating an output image by recording imaging information including a pixel signal obtained by a light field camera as it is may be considered. At this time, if the monitor 9a is replaced with one window on the PC, the instruction with the finger is an instruction with the mouse, and the manual focus operation is replaced with the refocus after shooting (manipulating the image generation surface to be developed), the book is easily obtained. The invention can be applied.

  As described above, according to the present invention, a high-quality image can be obtained even when vignetting occurs in the photographing optical system based on information on the photographing lens.

[Other embodiments]
Each process shown in the embodiment described above is realized by reading a program for realizing the function of each process from the memory and executing it by the CPU of the camera system control circuit 5.

  Note that the present invention is not limited to the configuration described above, and all or some of the functions of each process may be realized by dedicated hardware. The above-described memory may be composed of a non-volatile memory such as a magneto-optical disk device or a flash memory, a recording medium such as a CD-ROM that can only be read, and a volatile memory other than the RAM. Moreover, you may comprise from the computer-readable / writable recording medium by those combination.

  In addition, each process may be performed by recording a program for realizing the function of each process on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium. . Here, the “computer system” includes an OS and hardware such as peripheral devices. Specifically, the program read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. After that, the CPU of the function expansion board or function expansion unit performs part or all of the actual processing based on the instructions of the program, and the functions of the above-described embodiments are realized by the processing.

  The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” includes a medium that holds a program for a certain period of time. For example, a volatile memory (RAM) inside a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line.

  The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  A program product such as a computer-readable recording medium in which the above program is recorded can also be applied as an embodiment of the present invention. The above program, recording medium, transmission medium, and program product are included in the scope of the present invention.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

Claims (13)

In a display device for displaying a pixel signal obtained by photoelectrically converting a subject image by an image sensor,
Signal acquisition means for acquiring information including pixel signals obtained by a light field camera;
Display means for displaying the acquired pixel signal;
Display area dividing means for dividing the display screen of the display means into a plurality of divided display areas;
A baseline direction control means for setting a baseline length direction used for distance measurement;
In one area of the plurality of divided display areas, based on the information acquired by the signal acquisition means, out of more than two pupil areas divided in the baseline length direction set by the baseline direction control means A display device comprising display control means for displaying the pixel signals corresponding to different non-adjacent pupil regions.   The display area dividing means further divides the one area into two areas based on the baseline length direction set by the baseline direction control means, and the display control means divides the one area into the two divided areas. The display device according to claim 1, wherein each of the pixel signals corresponding to different pupil regions is displayed.   3. The display device according to claim 2, wherein the display area dividing unit further divides the one of the plurality of divided display areas into two areas in a direction orthogonal to the set base line length direction.   Ranging area control means for setting a ranging area on the display screen is provided, and the display area dividing means divides the display screen into the plurality of divided display areas according to the setting of the ranging area by the ranging area control means. The display device according to claim 1, wherein the display control unit sets the one area as the distance measurement area.   The display control means corresponds to a different non-adjacent pupil area among the more than two pupil areas divided in the baseline length direction set by the baseline direction control means in one of the plurality of divided display areas. The display device according to claim 1, wherein the pixel signals to be added are displayed.   The display control unit performs different color adjustments on the pixel signals corresponding to different non-adjacent pupil regions among the more than two pupil regions divided in the baseline length direction set by the baseline direction control unit. 6. The display device according to claim 5, wherein addition is performed. An imaging optical system;
An image sensor;
Pupil dividing means for restricting a light beam incident on a pixel on the image sensor to only a specific pupil region of the photographing lens and dividing it into more than two pupil regions;
An imaging apparatus comprising: the display device according to claim 1.   8. The pupil division unit is a microlens array disposed on a light receiving surface of the imaging device, and each microlens is provided corresponding to an array including a predetermined number of pixels. The imaging device described in 1. In a display method for displaying on a display means a pixel signal obtained by photoelectrically converting a subject image by an image sensor,
A signal acquisition step of acquiring information including pixel signals obtained by a light field camera;
A display area dividing step of dividing the display screen of the display means into a plurality of divided display areas;
A baseline direction control step for setting a baseline length direction used for distance measurement;
In one region of the plurality of divided display regions, based on the information acquired in the signal acquisition step, out of more than two pupil regions divided in the baseline length direction set in the baseline direction control step A display method comprising a display control step of displaying the pixel signals corresponding to different non-adjacent pupil regions. Computer
In a control method of a display device for displaying on a display means a pixel signal obtained by photoelectrically converting a subject image by an image sensor,
Signal acquisition means for acquiring information including pixel signals obtained by a light field camera;
Display area dividing means for dividing the display screen of the display means into a plurality of divided display areas;
Baseline direction control means for setting the baseline length direction used for ranging,
In one region of the plurality of divided display regions, based on the information acquired by the signal acquisition unit, of the more than two pupil regions divided in the baseline length direction set by the baseline direction control unit A program that functions as display control means for displaying the pixel signals corresponding to different pupil regions that are not adjacent to each other.   The computer-readable recording medium which recorded the program of Claim 10.   The program which makes a computer function as each means of the display apparatus as described in any one of Claims 1 thru | or 6.   A storage medium storing a program that causes a computer to function as each unit of the display device according to any one of claims 1 to 6.

Images