JP5832353B2 - Imaging device - Google Patents

Description

  The present invention relates to an image pickup apparatus, and more particularly to an image pickup apparatus capable of shooting using a coded aperture.

  In the technical field of imaging devices, a technique is known in which an image is acquired using a plurality of point spread functions (PSFs), and processing such as blur correction and subject distance estimation is performed from the acquired image. In this case, an encoded aperture (encoded pupil) is used in order to improve the robustness of the restoration / estimation process (photographing using such an encoded aperture is performed). Hereafter referred to as “encoded aperture photography”). For example, a technique is known in which a lens incorporating a coded aperture of a different pattern is changed to change the PSF, and a plurality of images are acquired with a single imaging device. For example, in Patent Document 1, a pinhole-shaped coded aperture is used, and subject light incident on a photographing lens is separated into a plurality of light beams by a prism, and the optical path lengths (focused states) for the light beams are arranged differently. It describes that three types of encoded aperture images are acquired by imaging using a plurality of imaging elements.

Japanese Patent Laid-Open No. 11-337313

  However, such a conventional technique cannot easily perform imaging with a plurality of PSFs and acquisition of a plurality of images with different degrees of blurring (focused state) in coded aperture imaging. For example, as described above, when a lens incorporating a coded aperture with a different pattern is exchanged and shooting is performed a plurality of times, only a stationary object can be shot because the shooting timing varies between images. Because of this, shooting was time consuming and time consuming. Further, when the optical path is separated by the prism as in Patent Document 1, there is a problem that the imaging apparatus becomes large and complicated, and the cost increases.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an imaging apparatus capable of performing coded aperture imaging quickly and easily.

  In order to achieve the above object, an imaging apparatus according to a first aspect of the present invention is a photographic lens having a plurality of regions, wherein the plurality of regions have independent characteristics, and a plurality of regions. An encoding opening provided corresponding to each of the plurality of light receiving sensors provided corresponding to each of the plurality of areas, the encoding opening corresponding to any of the plurality of areas and the corresponding one of the areas And an image generation means for generating a plurality of images corresponding to each of a plurality of regions from image pickup signals of the plurality of light receiving sensors. And the characteristic is at least one of a focal length and a focusing distance.

  In the imaging device according to the first aspect, a plurality of areas have independent characteristics (at least one of a focal length and a focusing distance), and a code provided corresponding to each of the plurality of areas. A plurality of images are generated from the aperture. That is, since a plurality of images corresponding to each area of the photographic lens can be generated at the same time, it is possible to shoot both still images and moving images without taking time and effort for shooting. In the first aspect, the generation of a plurality of images is realized by the fact that the plurality of areas of the photographing lens have independent characteristics, so that the lenses are exchanged to change the aperture pattern as in the prior art described above. Therefore, it is not necessary to separate the optical path with a prism in order to obtain images with different in-focus states, and the configuration is simple, the size can be reduced, and cost can be reduced.

  In the first aspect, the characteristic of each area (at least one of the focal length and the focusing distance) is “independent” means that the characteristic of one area does not depend on the characteristics of other areas. The focal length and the in-focus distance may be the same or different. In the first aspect, the number of photographing lenses may be one, or a plurality of lenses may be combined to have a plurality of regions as a whole. The characteristics of each region may be fixed or may be changed. Furthermore, the pattern of the coded aperture may be the same or different in each region. Even if the coded aperture pattern is the same in each region, a plurality of images with different in-focus states can be obtained if the characteristics of the photographic lens (for example, in-focus distance) are different, and the coded aperture pattern is different in each region. For example, the PSF differs depending on the opening pattern, and as a result, a plurality of images with different blur conditions (focused states) are obtained. The opening pattern may be different in some of the plurality of regions.

  In the first aspect, the “focusing distance” refers to a distance FD represented by the following expression, that is, a distance from the light receiving surface of the light receiving sensor to a subject in focus with the light receiving sensor.

(Equation 1)
FD = a + b (1)
FD: In-focus distance a: Distance between lens and light-receiving surface of light-receiving sensor b: Distance between lens and in-focus position If the focal length is f, 1 / f = (1 / a) + (1 / b) Even if the focal length f is the same, the focusing distance FD differs depending on the combination of the distances a and b. Conversely, even if the focal length f is different, the in-focus distance FD can be made the same by combining the distances a and b.

  When a photographic lens in which a plurality of areas have independent characteristics as in the first aspect is used, if the subject images formed on the light receiving sensor by the areas of the photographic lens are different, the different subject images are overlapped. A difference in characteristics between subject images is perceived as a reduction in image quality. Factors that cause differences in subject images are mainly (1) size difference between subject images, (2) difference in blur amount between subject images, and (3) parallax shift between subject images. The characteristics of each region (focal length, The relationship with the (focus distance) is as follows.

  (I) When both the focal length and the in-focus distance are different between regions, a size difference, a blur amount difference, and a parallax shift occur between images corresponding to the regions.

  (Ii) When the focal lengths are the same in the regions but the in-focus distances are different, a blur amount difference and a parallax shift occur between images corresponding to the regions.

  (Iii) When the focal length is different between the regions and the in-focus distance is the same, a size difference and a parallax shift of the subject image occur between images corresponding to the regions.

  (Iv) When both the focal length and the in-focus distance are equal between regions, a parallax shift occurs between images corresponding to those regions.

  When a photographic lens in which a plurality of areas have independent characteristics is used, the difference between the subject images generated according to the characteristics of each area as described in (i) to (iv) above in a normal sensor, that is, in one area. The image quality deteriorates due to the influence of light beams that have passed through other areas in the corresponding image (crosstalk between areas).

  Therefore, in the imaging apparatus according to the first aspect of the present invention, a light receiving sensor that selectively receives light by splitting a light beam that has passed through any of the plurality of regions of the photographing lens described above and the coded aperture corresponding to the region. The influence of crosstalk between regions is removed using an image sensor having a (pupil directivity sensor), and a plurality of images corresponding to each region of the photographing lens can be acquired independently. The pupil division and selective light reception of the light beam by the light receiving sensor can be realized by an optical element such as a light shielding surface, a light shielding member, a liquid crystal shutter, or a liquid crystal prism provided in front of the light receiving surface.

  In this manner, the imaging apparatus according to the first aspect can perform coded aperture shooting quickly and easily and obtain a plurality of images with good image quality.

  In the imaging device according to the second aspect of the present invention, in the first aspect, each of the plurality of regions has a different coded aperture pattern. Since the aperture pattern when performing coded aperture shooting varies depending on conditions such as the type and distance of the subject such as a still life, a person, and a landscape, the image pickup apparatus according to the second aspect has different coded aperture patterns for each of the plurality of regions. By having it, it is possible to change the PSF by setting a plurality of opening patterns according to the subject, and it is possible to quickly and easily acquire a plurality of images with different blur conditions (focused states).

  The imaging device according to a third aspect of the present invention includes, in the first or second aspect, an opening pattern changing unit that changes a pattern of the coded opening. In the third aspect, an image can be acquired with a desired aperture pattern in consideration of the fact that the preferred aperture pattern when performing coded aperture imaging as described above varies depending on the subject. In the third mode, the opening pattern can be changed by inserting or removing an optical member corresponding to the opening pattern in the optical path of the photographing lens or using a liquid crystal shutter that can electrically change the opening pattern.

  In any one of the first to third aspects, an imaging apparatus according to a fourth aspect of the present invention includes distance information acquisition means for acquiring subject distance information based on a plurality of generated images. The distance information acquired in this way can be used for measuring the three-dimensional shape of the subject. In the fourth aspect, a distance image may be generated based on the acquired distance information.

  In the image pickup apparatus according to the fifth aspect of the present invention, in the fourth aspect, the image generation means generates an omnifocal image from the acquired distance information and the acquired plurality of images. The omnifocal image generated (restored) in this way can be widely used in the field of surveying / measurement and the field of image processing, such as measurement of the three-dimensional shape of the subject, like the distance information described above.

  In any one of the first to fifth aspects, an imaging apparatus according to a sixth aspect of the present invention includes a focal length changing unit that changes the focal length of at least one of the plurality of areas. In the sixth aspect, an image having a desired focal length can be acquired in accordance with the subject by changing the focal length. In the sixth aspect, the change of the focal length can be realized by various methods such as moving the focal length changing lens in the optical axis direction or inserting / removing it in the optical path of the photographing lens.

  In any one of the first to sixth aspects, an imaging apparatus according to a seventh aspect of the present invention includes a focusing distance changing unit that changes a focusing distance of at least one of the plurality of areas. In the seventh aspect, by changing the focus distance, an image having a desired focus distance can be acquired in accordance with the subject. In addition, in the seventh aspect, the focus distance can be changed by moving the focus distance changing lens in the optical axis direction or inserting / removing the lens in the optical path of the photographic lens as in the case of changing the focal length. Can be realized by various methods such as moving the lens in the direction of the optical axis.

  An imaging device according to an eighth aspect of the present invention is the imaging device according to any one of the first to seventh aspects, wherein the photographing lens is a photographing lens composed of two or more physically separated lenses, and a plurality of the photographing lenses. These regions have independent characteristics corresponding to combinations of two or more lenses. As described above, in the imaging apparatus according to the present invention, the photographing lens may be composed of a plurality of lenses, and the eighth aspect shows one aspect of the photographing lens composed of such a plurality of lenses. . As the photographing lens in the eighth aspect, for example, a plurality of lenses each corresponding to a plurality of regions are arranged with their optical axis direction positions separated from each other, and each of the plurality of lenses has an independent focal length. Is mentioned.

  As described above, according to the imaging apparatus according to the present invention, coded aperture imaging can be performed quickly and easily.

FIG. 1 is a block diagram illustrating a main configuration of the imaging apparatus 10. FIG. 2 is a diagram illustrating an example of the encoding aperture 11. FIG. 3 is a front view of the photographic lens 12. FIG. 4 is a diagram illustrating a state of selective light reception of a light beam in the image sensor 16. FIG. 5 is a diagram illustrating an example of the arrangement of the light receiving cells in the image sensor 16. FIG. 6 is a diagram illustrating a functional configuration of the CPU 40. FIG. 7 is a diagram illustrating a state of image acquisition in the imaging apparatus 10. FIG. 8 is a diagram illustrating an example of an image acquired by the imaging apparatus 10. FIG. 9 is a diagram illustrating an example of an omnifocal image in the imaging apparatus 10. FIG. 10 is a diagram illustrating an example in the case where the photographing lens includes two or more lenses.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for implementing an imaging apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

<Configuration of imaging device>
FIG. 1 is a block diagram showing a main configuration of the imaging apparatus 10. The overall operation of the image pickup apparatus 10 is controlled in an integrated manner by a central processing unit (CPU) 40, and programs necessary for the operation of the CPU 40 (programs used for image pickup processing, image generation / compositing processing, focusing distance change, etc., which will be described later). And parameters are stored in an EEPROM (Electronically Erasable and Programmable Read Only Memory) 46.

  The imaging apparatus 10 is provided with an operation unit 38 including a release button, a mode dial, a playback button, a MENU / OK key, a cross key, a BACK key, and the like. A signal from the operation unit 38 is input to the CPU 40, and the CPU 40 controls each circuit of the imaging device 10 based on the input signal as described later.

  The release button is an operation button for inputting an instruction to start shooting, and is composed of a two-stroke switch having an S1 switch that is turned on when half-pressed and an S2 switch that is turned on when fully pressed. The mode dial is a means for selecting a still image / moving image shooting mode, a manual / auto shooting mode, a shooting scene, and the like.

  The playback button is a button for switching to a playback mode in which a still image or a moving image of a photographed and recorded image is displayed on the liquid crystal monitor 30. The MENU / OK key is an operation key that has both a function for instructing to display a menu on the screen of the liquid crystal monitor 30 and a function for instructing confirmation and execution of selection contents. The cross key is an operation unit that inputs instructions in four directions, up, down, left, and right, and functions as a cursor moving operation means, a zoom switch, a frame advance button in the playback mode, and the like. The BACK key is used to delete a desired object such as a selection item, cancel an instruction content, or return to the previous operation state. These buttons and keys can also be used for operations necessary for image extraction and composition processing.

  In the photographing mode, image light indicating a subject is imaged on a light receiving surface of a solid-state imaging device (imaging device: hereinafter referred to as “CCD”) 16 through a photographing lens 12 (photographing lens) and an encoding aperture 11. FIG. 2 is a diagram illustrating an example of the encoding aperture 11. The encoded aperture is set as a pattern of a portion that transmits the light beam and a portion that shields light (the hatched portion in FIG. 2) in the liquid crystal shutter 11-1. In this embodiment, when the user operates the operation unit 38, the aperture pattern changing function of the CPU 40 is set. f2 (described later) controls the liquid crystal shutter 11-1, thereby changing the opening pattern (and the PSF corresponding thereto). The pattern of the encoding aperture 11 may be set / changed in consideration of conditions such as the type and distance of the subject, the ease and accuracy of the restoration process, and the same pattern regardless of the area of the photographing lens 12. It may be a different pattern for each region. FIG. 2 shows a case where the encoding aperture 11 is composed of different patterns of encoding apertures 11a (lower half of FIG. 2) and 11b (upper half of FIG. 2) corresponding to the area of the taking lens 12 (accordingly, each area). In the case of different PSFs).

  In the present embodiment, the aperture pattern is changed by the liquid crystal shutter 11-1, but an optical member in which a plurality of encoded apertures having different patterns are arranged is appropriately moved and rotated to be on the optical axis of the photographing lens 12. You may make it change a pattern by arrange | positioning. When the aperture pattern is not changed, an optical member having a specific aperture pattern may be fixedly provided in place of the aperture pattern changing function f2 and the liquid crystal shutter 11-1.

  In the present embodiment, the encoding aperture 11 may be disposed on the front focal plane of the photographic lens 12, and the encoding aperture 11, the photographic lens 12, and the CCD 16 may constitute a telecentric optical system. However, in the present invention, the arrangement of the encoding aperture 11, the photographic lens 12, and the CCD 16 is not limited to such a mode, and the encoding aperture 11 is located at a position other than the front focal plane (including the rear of the photographic lens 12). You may arrange.

  FIG. 3 is an external view of the photographic lens 12. The photographic lens 12 includes a region 12a having a long focusing distance (hereinafter referred to as a far focusing region) 12a and a region 12b (hereinafter referred to as a near focusing region) having a focusing distance shorter than the far focusing region 12a. As shown in FIG. 3, half-moon shaped regions are provided above and below the lens center O1, as viewed from the front, and form a far focusing region 12a and a near focusing region 12b in this order from the bottom. The focus distances of the far focus area 12a and the near focus area 12b are independent of the focus distances of the other areas. A photographic lens whose characteristics are independent of each other can be realized by changing the material and shape of each region.

  Although the focal lengths of the respective areas in the photographing lens 12 are equal, the characteristics of the respective areas of the photographing lens in the imaging apparatus of the present invention are not limited to such conditions, and the focal distances between the respective areas. And at least one of the focal lengths is independent, the specific values may be the same or different. Further, in these areas, specific values of the focus distance and the focal distance may be set according to the purpose of photographing.

  In the example of FIG. 3, each region is formed in a half-moon shape, but a circular region arranged at the center of the lens and an annular region around it (one is a far focusing region, the other is a near focusing region) And may be formed. In the example of FIG. 3, the areas of the far focus area 12a and the near focus area 12b are made equal, but the area ratio of these areas is different from the above depending on the characteristics of the optical system, the shooting purpose, shooting conditions, etc. May be set. Further, the number of regions is not limited to 2, but may be 3 or more.

  The light beam that has passed through the far focusing area 12a and the near focusing area 12b of the photographing lens 12 is incident on each photosensor of the CCD 16. As shown in FIG. 4, the CCD 16 includes a far-image light-receiving cell 16a that receives the light beam that has passed through the far-focus area 12a of the photographing lens 12, and a near-image light-receiving cell that receives the light beam that has passed through the near-focus area 12b. 16b. The light receiving cells 16a and 16b selectively receive light beams that have passed through the far focus region 12a and the near focus region 12b by the microlens ML and the light shielding films 18a and 18b provided on the front surface of the light receiving unit 17, respectively. Therefore, the light shielding films 18a and 18b have different shapes. Instead of providing a light shielding film on the front surface of the light receiving unit 17, a light shielding member or a liquid crystal shutter may be provided on the front surface of the microlens ML.

  It is preferable that the ratio of the number of the light receiving cells 16a and 16b is substantially equal to the area ratio of the focusing regions 12a and 12b corresponding to the light receiving cells 16a and 16b. FIG. 5 shows an example of the arrangement of the light receiving cells in the image sensor 16. In this embodiment, since the areas of the far focusing area 12a and the near focusing area 12b are equal, the numbers of the light receiving cells 16a and 16b are also equal. The light receiving cells 16a and 16b are preferably arranged so that the image quality does not deteriorate in a specific region or direction in the generated image, and interpolation of pixel data loss due to a mixture of cells corresponding to each of a plurality of regions is performed. It is preferable to appropriately compensate by such as.

The CPU 40 performs charge accumulation time (shutter speed) in the CCD 16, image signal readout control from the CCD 16, and the like via a CCD control unit (not shown ). The signal charge accumulated in the CCD 16 is read out as a voltage signal corresponding to the signal charge based on the readout signal applied from the CCD control unit and added to the analog signal processing unit 20.

  The analog signal processing unit 20 samples and holds the R, G, and B signals for each pixel by the correlated double sampling process on the voltage signal output from the CCD 16, amplifies it, and adds the amplified signal to the A / D converter 21. The A / D converter 21 converts analog R, G, and B signals that are sequentially input into digital R, G, and B signals and outputs them to the image input controller 22. A MOS type image pickup device can be used in place of the CCD 16, but in this case, the A / D converter 21 is often built in the image pickup device, and the correlated double sampling is not required.

  The digital signal processing unit 24 performs predetermined processing such as offset control, gain control processing including white balance correction and sensitivity correction, gamma correction processing, YC processing, etc., on the digital image signal input via the image input controller 22. Perform signal processing.

  The image data processed by the digital signal processing unit 24 is input to the VRAM 50. The VRAM 50 includes an A area and a B area each storing image data representing an image of one frame, and image data representing an image of one frame is rewritten alternately between the A area and the B area. Thus, the written image data is read from an area other than the area where the image data is rewritten. The image data read from the VRAM 50 is encoded by the video encoder 28 and output to the liquid crystal monitor 30, whereby the subject image is displayed on the liquid crystal monitor 30. The liquid crystal monitor 30 employs a touch panel, displays an acquired image, and allows a user operation via the screen.

  When the first release button (half-press) of the release button of the operation unit 38 is pressed, the CPU 40 starts an AE operation. The image data output from the A / D converter 21 when the release button is half-pressed is taken into the AE detection unit 44.

  The CPU 40 calculates the brightness of the subject (shooting Ev value) from the integrated value of the G signal input from the AE detection unit 44, determines the electronic shutter (shutter speed) of the CCD 16 based on this shooting Ev value, and the result Based on the above, the charge accumulation time in the CCD 16 is controlled.

  When the AE operation ends and the release button is pressed in the second stage (full press), the image data corresponding to the far-focus area 12a and the near-focus area 12b is sent to the A / D converter in response to the press. 21 is input from the image input controller 22 to the memory (SDRAM) 48 and temporarily stored.

  After temporary storage in the memory 48, image files are generated through signal processing such as YC processing in the digital signal processing unit 24 and compression processing to a JPEG (joint photographic experts group) format in the compression / decompression processing unit 26. Are read out by the media controller 52 and recorded in the memory card 54. The image recorded on the memory card 54 can be reproduced and displayed on the liquid crystal monitor 30 by operating the reproduction button of the operation unit 38.

<Functional configuration of CPU>
As will be described later, the imaging apparatus 10 performs focus distance control of the photographing lens 12 and image generation / combination. Such processing is mainly performed by control of the CPU 40. FIG. 6 is a functional block diagram showing functions of the CPU 40 for performing such processing. The CPU 40 has an image generation function f1 (image generation means), an opening pattern change function f2 (opening pattern change means), and distance information acquisition. It has a function f3 (distance information acquisition means). Hereinafter, an outline of each function will be described.

  The image generation function f1 is a function for generating an image corresponding to each region of the photographing lens 12 using an imaging signal output from the CCD 16 and generating an omnifocal image from these images. The image generation function f1 also generates a distance image from the distance information acquired by the distance information acquisition function f3.

  As described above, the opening pattern changing function f2 is a function for changing the opening pattern of the encoded opening 11 by controlling the liquid crystal shutter 11-1.

  The distance information acquisition function f3 is a function for acquiring distance information of the subject from the image acquired by the image generation function f1.

<Image acquisition>
Next, multifocus image acquisition by the imaging apparatus 10 will be described. FIG. 7 is a diagram showing how images i1 and i2 (encoded aperture images) corresponding to the far focus area 12a and the near focus area 12b of the photographic lens 12 are acquired. It is as follows.

a1, a2: Distance between the lens and the light receiving surface in the far focus area 12a and the near focus area 12b b1, b2: Distance between the lens and the subject in the far focus area 12a, the near focus area 12b FD1, FD2: Far focus In-focus distance Q1, Q2 of subject 12a and near-focus region 12b: subject Therefore, in the situation of FIG. 7, subject Q1 at distance b1 is in-focus at far-focus region 12a, and subject Q2 at distance b2 is close-in Focusing is performed in the focal region 12b. FIG. 8 is an example of images i1 and i2 acquired in each focus area in the situation of FIG. An image i1 shown in FIG. 8A shows an image acquired in the far focus area 12a. A subject Q1 at a distance b1 is in focus, and a subject Q2 at a distance b2 different from the distance b1 is a difference between the distances b1 and b2. It is blurred according to. On the other hand, an image i2 shown in FIG. 8B shows an image acquired in the near focus area 12b. A subject at a distance b2 is in focus, and a subject Q1 at a distance b1 different from the distance b2 is a difference between the distances b2 and b1. It is blurred according to.

  As described above, in the imaging apparatus 10 according to the present embodiment, the coded aperture photographing with a plurality of PSFs is performed by the coded aperture 11, the photographing lens 12, and the CCD 16 including the light receiving cells 16a and 16b capable of selective light reception. And a plurality of images i1 and i2 having different degrees of blurring (focused state) can be acquired simultaneously. Since a plurality of images can be acquired at the same time, it does not take time and effort to shoot, and there is no deviation in shooting timing between images. Further, by changing the opening pattern by the opening pattern changing function f2 and the liquid crystal shutter 11-1 as described above, an image is acquired with a desired opening pattern (and a PSF corresponding to the subject) and the photographing purpose. it can. In the above description, it is not particularly limited whether the image is a still image or a moving image, but either a still image or a moving image can be taken. Even when a moving image is shot, the shooting timing is not shifted between areas, and an image with good image quality is obtained, which is advantageous for subsequent image processing.

  As described above, the imaging apparatus 10 can quickly and easily perform coded aperture shooting and acquire a plurality of images with good image quality.

  Further, in the imaging device 10, the distance information acquisition function f3 of the CPU 40 acquires subject distance information from the images i1 and i2, and the image generation function f1 acquires both the subjects Q1 and Q2 from the images i1 and i2 and the distance information. (Omnifocal image) and distance image can be obtained. FIG. 9 is an example of the omnifocal image i3 generated in this way. The images i1 to i3 and the distance information (distance image) can be used in various fields such as measurement of the three-dimensional shape of the subject and synthesis with other images.

  In the imaging apparatus 10, the distance information of the subject can be calculated by various methods. As described in Japanese Patent Application Laid-Open No. 2011-124712, it may be calculated using the phase difference information of the light receiving sensor, or by comparing the contrast of a plurality of imaging signals acquired at different lens positions. The calculation may be performed, and various methods can be used. Similarly, an omnifocal image can also be acquired by various methods. References that describe how to acquire distance information and omnifocal images include, for example, “Coded Aperture Pairs for Depth from Defocus and Defocus Deblurring (Changyin Zhou, Stephen Lin, and Shree Nayar; International Journal of Computer Vision (IJCV), Volume 93, Number 1, Pages 53-72, 2011) ”,“ Programmable Aperture Camera Using LCoS (Hajime Nagahara, Changyin Zhou, Takuya Watanabe, Hiroshi Ishiguro, and Shree Nayar; ECCV 2010) ”,“ Coded Aperture Pairs for Depth from Defocus (Changyin Zhou, Stephen Lin, and Shree Nayar); ICCV 2009 ”.

<Modification of imaging device>
In the above-described embodiment, the case where the photographing lens is a lens as illustrated in FIG. 3 has been described. However, the photographing lens in the imaging apparatus according to the present invention is not limited to such a mode. FIG. 10 is a diagram showing another aspect of the photographing lens. The photographic lens 12 ′ shown in FIG. 10 is a photographic lens composed of two or more physically separated lenses, and a plurality of areas of the photographic lens have independent characteristics corresponding to combinations of two or more lenses. (At least one of the focal distance and the focal distance ; hereinafter, the case of the focal distance will be described ). In FIG. 10, L1 indicates the optical axis of the photographing lens 12 ′. In the photographing lens 12 ′, as shown in FIG. 10A, half-moon shaped regions are provided above and below the lens center O1 ′ when viewed from the front, and the far focusing region 12a ′ and the near focusing region are sequentially arranged from the bottom. 12b ′. These two in- focus areas function as two lenses that are physically separated, and constitute a photographic lens 12 'as a whole. In these areas, a specific value of the in- focus distance may be set according to the purpose of photographing. As shown in FIG. 10B, the far focusing area 12a ′ and the near focusing area 12b ′ may be arranged at different positions in the optical axis direction.

  In the imaging apparatus according to the present invention, the characteristics of the photographing lens (at least one of the in-focus distance and the focal distance) may be changed. The change of the characteristics can be realized by various methods such as moving the entire photographing lens or moving a part of the photographing lens composed of a plurality of lenses. Further, any one of the photographing lenses including two or more lenses as shown in FIG. 10 may be rotated and moved. Such movement and rotation of the lens may be performed in accordance with the rotation of the lens barrel by the photographer, or may be performed by the CPU 40 controlling the motor and PZT (piezo element). In this way, by changing the characteristics of the photographing lens, a plurality of images can be acquired simultaneously with desired characteristics and combinations thereof. When the photographing lens (or a part thereof) is moved and rotated in this way to change the focal distance or focal distance, the CPU 40 has a focal distance / focus distance changing function f4, and the imaging apparatus is a motor. -Provide a lens driving unit composed of a driver or the like.

  Although one embodiment of the present invention has been described above, the embodiment of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Imaging device, 11 ... Encoding aperture, 11-1 ... Liquid crystal shutter, 12, 12 '... Shooting lens, 12a, 12a' ... Far focus area | region, 12b, 12b '... Near focus area | region, 16 ... Solid imaging Element (CCD), 16a ... far light receiving cell, 16b ... near light receiving cell, 18a, 18b ... light shielding film, 30 ... liquid crystal monitor, 38 ... operation unit, 40 ... CPU, 46 ... EEPROM, 48 ... memory, 54 ... Memory card, a1, a2 ... Lens-light receiving surface distance, b1, b2 ... Lens-subject distance, FD1, FD2 ... In-focus distance, Q1, Q2 ... Subject, i1-i3 ... Image

Claims (7)

A single optical system including an imaging lens having a plurality of regions, and an optical system having a characteristic of said plurality of regions are each independently
A coded opening provided corresponding to each of the plurality of regions, the coded opening having a different pattern corresponding to each of the plurality of regions ;
A plurality of light receiving sensors provided corresponding to each of the plurality of regions, wherein a light beam that has passed through any one of the plurality of regions and a coded aperture corresponding to any one of the regions is selected by pupil division. An image sensor having a plurality of light receiving sensors for receiving light automatically,
Image generating means for generating a plurality of images corresponding to each of the plurality of regions from imaging signals of the plurality of light receiving sensors;
With
Said properties Ri least one der of the focal length and focus distance,
Each of the plurality of light receiving sensors includes a light shielding film provided on a light receiving surface and having a shape corresponding to any shape of the plurality of regions, and the imaging element includes the plurality of light shielding films. The selective light reception is performed by receiving a light beam that has passed through one of the regions and shielding a light beam that has passed through another region,
Imaging device. The imaging apparatus according to claim 1, further comprising an opening pattern changing unit that changes a pattern of the encoded opening. The imaging apparatus according to claim 1, further comprising a distance information acquisition unit that acquires distance information of a subject based on the plurality of generated images. The imaging apparatus according to claim 3, wherein the image generation unit generates an omnifocal image from the acquired distance information and the generated plurality of images. The imaging apparatus according to claim 1, further comprising a focal length changing unit that changes a focal length of at least one of the plurality of areas. The imaging apparatus according to claim 1, further comprising a focus distance changing unit that changes a focus distance of at least one of the plurality of areas. The photographing lens is a photographing lens composed of two or more physically separated lenses, and a plurality of regions of the photographing lens have independent characteristics corresponding to the combination of the two or more lenses, The imaging device according to any one of claims 1 to 6.

Images