JP2012194487A - Imaging device, imaging method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately execute multiple AF function in consideration of focal distance deviation which is different to each individual device and occurs according to a position in a photographing screen of a photographing optical system.SOLUTION: An imaging device includes: an optical lens unit 11 including a focus lens for moving a focal position; a CMOS image sensor 12 for projecting a subject image obtained from the optical lens unit 11 onto an imaging surface and outputting an image signal; a program memory 23 that previously stores focus error with respect to a focus state at a reference position at the time of photographing an equidistant subject image for each of a plurality of positions in the subject image projected onto the imaging surface; a CPU 21 for determining respective focal positions of the plurality of positions in the subject image projected onto the imaging surface, correcting a determination result based on a store content of the program memory 23, and deciding a moving position of the focus lens of the optical lens unit 11 based on the corrected determination result.

Description

  The present invention relates to an imaging apparatus, an imaging method, and a program suitable for a digital camera that measures a plurality of areas in an image to be captured and executes an AF (automatic focus) function.

  A camera having a multi-AF function is generally commercialized in which a plurality of AF areas are provided in a shooting screen, and a final focus position is determined based on a result of focusing in each AF area. Further, in a camera having this type of multi-AF function, image data obtained by capturing subject images at a plurality of different focal positions that have been changed while changing the focal position with reference to the original in-focus position. A technique for executing an auto bracket function related to the in-focus distance, which is acquired as image data for storage, can be considered. (For example, Patent Document 1)

JP 2010-128018 A

  By the way, when shooting a flat subject with the same distance at any position in the shooting screen using the AF function, there is an individual camera even if it is accurately focused in the center of the shooting screen. Depending on the characteristics of the optical lens system that is being used, the error in the mounting angle of the image sensor, etc., it is far from the original focus position on the upper left side of the screen, for example, and closer to the original focus position on the lower right side. As described above, depending on the position in the screen, there may occur a situation in which an accurate in-focus distance is shifted.

  Therefore, in such a camera in which the accurate focus distance is shifted at a plurality of positions in the shooting screen, the plurality of AF areas in the shooting screen are focused by the multi-AF function to obtain a final focus position. Therefore, since the reference is shifted for each AF area, an accurate determination cannot be made. It is also possible to execute.

  In this regard, when the technology described in the above-mentioned patent document is applied, the amount of focus distance shift for each AF area that the photographing optical system potentially has, and when the apparatus intentionally changes the imaging The amount of change in the in-focus distance is not necessarily the same, and there is a high possibility that imaging at the correct in-focus distance will not be executed. On the other hand, because there is definitely an image that is not focused on the main subject by bracket shooting, the capacity of the medium for storing the image data acquired by imaging is greatly wasted, etc. It is impossible to deal with a camera with an accurate in-focus distance.

  The present invention has been made in view of the above circumstances, and its purpose is to take into account a shift in the focusing distance that varies depending on the position of the photographing optical system in the photographing screen, which differs for each device. Another object of the present invention is to provide an imaging apparatus, an imaging method, and a program that can accurately execute the multi-AF function.

  One embodiment of the present invention includes a photographic lens optical system including a focus lens that moves a focus position, an imaging element that irradiates an imaging surface with a subject image obtained from the photographic lens optical system, and outputs the image signal. A focus error storage unit that stores in advance a focus error from a focus state at a reference position when shooting a subject image at an equal distance for each of a plurality of positions in a subject image irradiated on the surface; and the imaging surface And a correction for correcting the determination result of the focus determination means based on the contents stored in the focus error storage means. And a focus control means for determining the movement position of the focus lens of the photographing lens optical system based on the determination result of the focus determination means corrected by the correction means.

  According to the present invention, it is possible to accurately execute the multi-AF function in consideration of the shift in the focusing distance that varies depending on the position of the photographing optical system, which differs depending on the individual device.

1 is a block diagram showing a schematic configuration of a functional circuit of a digital camera according to an embodiment of the present invention. The figure which shows the relationship between the deviation | shift amount of the focusing distance for every multi AF area which concerns on the same embodiment, and correction | amendment. The figure which illustrates the structure of the AF area correction table previously stored in the program memory according to the embodiment. 6 is a flowchart showing the processing content of still image shooting in the shooting mode according to the embodiment. The figure which shows the correction | amendment operation | movement of the focusing distance for every multi AF area which concerns on the same embodiment.

  Hereinafter, an embodiment in which the present invention is applied to a digital camera will be described with reference to the drawings.

  FIG. 1 shows a circuit configuration of a digital camera 10 according to the present embodiment. In the figure, a light image of a subject is incident on an image pickup surface of an image pickup element, for example, a CMOS image sensor 12 through an optical lens unit 11 disposed on the front surface of the camera casing.

  In a monitoring state, also referred to as through image display or live view image display, an image signal obtained by imaging with the CMOS image sensor 12 is sent to the AGC / A / D conversion unit 13 to perform correlation square sampling, automatic gain adjustment, A / D conversion processing is executed and digitized. The digital image data is held in the buffer memory 14 via the system bus SB.

  The image processing unit 15 appropriately performs necessary image processing on the image data held in the buffer memory 14. In the image processing unit 15, digital development processing, specifically pixel interpolation processing, gamma correction processing, is performed on image data corresponding to the configuration of the color filter of the Bayer array included in the CMOS image sensor 12 held in the buffer memory 14. By performing demosaic processing such as matrix operation, the image data is converted into luminance color difference (YUV) image data.

  The image processing unit 15 creates image data in which the number of pixels and gradation bits are greatly reduced for display from the developed image data, and sends the image data to the display unit 16 via the system bus SB. The display unit 16 displays a through image based on the sent image data.

  The display unit 16 includes, for example, a color liquid crystal panel with a backlight and its controller. A touch panel unit 17 using a transparent conductive film is formed integrally with the upper portion of the screen of the display unit 16.

  When the user touches the surface of the touch panel unit 17 with a finger or the like, the touch panel unit 17 calculates the position of the operation coordinate and sends the calculated coordinate signal to the CPU 21 described later via the system bus SB.

  Similarly to the optical lens unit 11, a microphone 18 is provided on the front surface of the camera casing, and the sound in the subject direction is input. The microphone 18 converts the input sound into an electrical signal and outputs it to the sound processing unit 19.

  The sound processing unit 19 converts the sound signal input from the microphone 18 into digital data when recording a single sound, capturing a still image with sound, and capturing a moving image. Further, the sound processing unit 19 detects the sound pressure level of the digitized sound data, and compresses the sound data in a predetermined data file format, for example, AAC (moving picture experts group-4 Advanced Audio Coding) format. An audio data file is created and sent to a recording medium to be described later.

  In addition, the sound processing unit 19 includes a sound source circuit such as a PCM sound source, uncompresses and converts the sound data file sent during sound reproduction into an analog signal, and a speaker 20 provided on the rear side of the housing of the digital camera 10. To sound a loud sound.

  The CPU 21 controls the above circuit in an integrated manner. The CPU 21 is directly connected to the main memory 22 and the program memory 23. The main memory 22 is composed of, for example, an SRAM and functions as a work memory. The program memory 23 is composed of an electrically rewritable nonvolatile memory such as a flash memory, for example, and fixedly stores various operation programs and data including a multi-AF control operation described later, an AF area correction table described later, and the like. .

  The CPU 21 reads the necessary program, data, etc. from the program memory 23 and executes the control operation of the entire digital camera 10 while temporarily developing and storing it in the main memory 22.

  Further, the CPU 21 executes control operations corresponding to various key operation signals directly input from the key operation unit 24 and coordinate signals corresponding to the touch operation from the touch panel unit 17.

  The key operation unit 24 includes, for example, a power key, shutter release key, zoom up / down key, shooting mode key, playback mode key, menu key, cursor (“↑”, “→”, “↓”, “←”) key, set key. , Release key, display key, etc.

  In addition to the AGC / A / D converter 13, the buffer memory 14, the image processor 15, the display unit 16, the touch panel unit 17, and the audio processor 19, the CPU 21 further includes a lens driver 25, via the system bus SB. The flash drive unit 26, the image sensor (IS) drive unit 27, and the memory card controller 28 are connected.

  The lens driving unit 25 controls the rotation of the lens DC motor (M) 29 in response to a control signal from the CPU 21, and a part of a plurality of lens groups constituting the optical lens unit 11, specifically zoom. The positions of the lens and the focus lens and the aperture degree of the aperture stop are individually controlled.

  The flash drive unit 26 receives a control signal from the CPU 21 during still image shooting, and drives the flash unit 30 including a plurality of white high-intensity LEDs to be lit in synchronization with the shooting timing.

  The image sensor driving unit 27 scans and drives the CMOS image sensor 12 according to the shooting conditions set at that time.

  The image processing unit 15 performs demosaic processing on the image data sent from the AGC / A / D conversion unit 13 and held in the buffer memory 14 at the time of photographing an image accompanying the shutter release key operation of the key operation unit 24, Further, if a predetermined data file format, for example, JPEG (Joint Photographic Experts Group), data compression processing such as DCT (Discrete Cosine Transform) or Huffman coding is performed to create an image data file with a greatly reduced data amount. The created image data file is recorded on the memory card 31 via the system bus SB and the memory card controller 28.

Further, the image processing unit 15 receives image data read from the memory card 31 via the memory card controller 28 in the reproduction mode via the system bus SB, holds the image data in the buffer memory 14, and then stores the buffer memory 14. The image data of the original size is obtained by decompression processing that decompresses the image data held in the recording process in the reverse procedure to the time of recording. After the data amount of the obtained image data is reduced, the display unit 16 is connected via the system bus SB. To display.
The memory card controller 28 is connected to the memory card 31 via the card connector 32. The memory card 31 is detachably attached to the digital camera 10 and is a memory for recording image data and the like serving as a recording medium of the digital camera 10, and internally includes a flash memory that is a non-volatile memory and a driving circuit thereof. And are provided.

Next, the operation of the above embodiment will be described.
Prior to a specific operation, a focus distance shift amount and correction basic concept for each multi AF area in the present embodiment will be described.

  FIG. 2 is a diagram showing the relationship between the amount of shift in the focusing distance for each multi-AF area and the correction. In the present embodiment, a case will be described in which the multi-AF area is formed with a total of nine frames of 3 × 3 in the approximate center of the shooting screen as illustrated.

  This digital camera is designed so that the optical axis of the camera is perpendicular to the wall surface of a flat subject, for example, a vertical wall surface, which is essentially the same in focus distance at the most standard focal length, aperture value, and distance to the subject. Assume that distance measurement to the subject is executed with the multi-AF function with 10 held horizontally. At this time, when the focus distance in the focus area E located at the center, that is, the drive step position of the focus lens in the optical lens unit 11 is set to “0” which is the reference position, other focus areas A to D, FIG. 2A shows the amount of focus distance deviation (number of focus lens drive steps) in F to I. FIG. The amount of deviation varies depending on errors such as the characteristics of the optical lens system and the mounting angle of the image sensor for each camera.

  In general, the focus lens is closest to the image sensor on the lens optical axis at infinity, and the position closest to the subject is the shortest shooting distance on the macro side. Start the search.

  Therefore, for example, in the focus area A, the amount of deviation of the focal length is “+4”, so that the focus is obtained at a distance closer to the reference focus area E by 4 steps. On the other hand, since the focal length shift amount is “−3” in the focus area I that is diagonally opposite the focus area A, the distance is 3 steps away from the reference focus area E. The focus is on.

  In this way, when the focal length shift amount is generated according to the position of each focus area, the original accurate focus distance cannot be obtained as it is, so that the focus areas A to D and F to I are used in advance. If the numerical value obtained by inverting the shift amount and the sign shown in FIG. 2A is held as a correction value, the correct focus distance is obtained by adding the correction value to the obtained focus distance. Will be able to. FIG. 2B shows correction values prepared in advance to cancel out the shift amount for each focus area.

  Unlike the principle described above, since the shift amount of each focus area differs depending on the focal length and aperture value in an actual digital camera, correction values for each focus area corresponding to the focal length and aperture value are stored in advance. It is necessary to keep.

  FIG. 3 illustrates the configuration of the AF area correction table stored in advance in the program memory 23 according to the present embodiment in accordance with the inspection result in the production process before factory shipment. FIG. 3A shows the identification position of each focus area.

  FIG. 3B shows the configuration of the AF area correction table. In this paper embodiment, for ease of explanation, for example, the optical lens unit 11 has an optical zoom function of about 4.8 times 28 [mm] to 135 [mm] in terms of the focal length of a 35 [mm] film camera. The aperture value at the focal length of the wide-angle system at a focal length of 28 [mm] to 35 [mm] is “F2.8”, and the standard system to the telephoto system at a focal length of 135 [mm] higher than that. Assuming that the maximum aperture value is “F4”, correction values for each focus area corresponding to each focal length and aperture value are stored in a table in the memory card controller 28 in advance.

  In FIG. 3B, the focal lengths are 28 [mm], 35 [mm], 50 [mm], 85 [mm], and 135 [mm], and the aperture values are “F2.8” and “F4”. The table in the case of “F8” and “F11” is illustrated, but the focal length and the aperture value, as well as the correction values corresponding to the respective intermediate values, are stored using a table having a larger capacity. Or may be calculated each time by linear interpolation calculation.

Next, the operation when a still image is shot in the shooting mode will be described.
The operation shown below shows the processing contents executed by the CPU 21 for taking a still image. The CPU 21 reads out the operation program and data stored in the program memory 23 and develops and stores them in the main memory 22. It will be executed.

  For example, when the digital camera 10 is upgraded, the operation program stored in the program memory 23 is stored in the program memory 23 when the digital camera 10 is shipped from the factory. To download and store new operation programs, data, and the like from the outside by connecting to.

  Note that the shutter release key of the key operation unit 24 has two operation strokes, and AF and AE (first-stage pressing operation that presses about ½ of the entire stroke, that is, a so-called “half-pressing” operation. It is assumed that shooting and recording are performed by a second-stage pressing operation that locks each state of (automatic exposure) and presses the entire stroke from that state, so-called “full pressing” operation.

FIG. 4 shows the processing contents under the still image shooting mode as described above.
At that location, the CPU 21 has the inside of the area in the image data held in the buffer memory 14 so that the in-focus state can be obtained in each of the plurality of areas in the subject image formed on the imaging surface of the CMOS image sensor 12. The focus lens position in the optical lens unit 11 is controlled by the lens driving unit 25 and the lens DC motor 29 so that the contrast evaluation values of the lens are maximized (step S101).

  FIG. 5A shows an example of the number of steps of driving the focus lens, which represents the in-focus distances in all the focus areas A to I, obtained by the process in step S101. Here, for example, the entire process of the focus lens of the optical lens unit 11 is set to 240 steps, and each area is in focus at substantially the center in the entire process.

  In this case, as described above, the minimum value “0” of the number of steps is infinity, and the maximum value “239” is the shortest shooting distance. The larger the value, the closer the subject in the area is to the digital camera 10. .

  Therefore, in the focusing result shown in FIG. 5A, the value of the focus area “A” is the largest, and if the focus distance is not corrected, the subject at the latest position is focused. Then, shooting is performed in a state in which focus output is performed in the focus area “A”.

  After the processing in step S101, the CPU 21 subsequently executes AE processing, and sets the optimum shutter speed and aperture value according to the exposure program diagram selected at that time (step S102).

  At this time, the CPU 21 matches the timing of reading the charges from the CMOS image sensor 12 by the image sensor driving unit 27 with the set shutter speed, while adjusting the aperture stop of the optical lens unit 11 to the set aperture value. Drive control is performed via the drive unit 25 and the lens DC motor 29.

  The CPU 21 sets the in-focus distance in all the focus areas A to I obtained in the immediately preceding step S101, the aperture value of the aperture stop set in the immediately preceding step S102, and the zoom of the optical lens unit 11 set at that time. Based on the lens position (focal length), a correction value for each focus area is read out from the AF area correction table shown in FIG. 4B, and the focus distance in all the focus areas A to I is corrected ( Step S103).

  FIG. 5B illustrates the correction value for each focus area read from the AF area correction table.

  Therefore, the in-focus distances in all the focus areas A to I after correction are as shown in FIG. 5C, and an area to be in focus is selected according to this content. In FIG. 5B, unlike the selection result in FIG. 5A, the value of the focus area “I” is the largest, and the entire captured image is set to the focus distance of the value of the focus area “I”. By doing so, it becomes possible to focus on the subject at the latest position.

  An image obtained with the focus distance corrected in this way is acquired from the CMOS image sensor 12, and is displayed as a through image by the image processing unit 15 (step S104).

  In this through image display state, the CPU 21 determines whether or not the shutter release key of the key operation unit 24 has been pressed halfway (step S105). If the shutter release key is half-pressed and it is determined that it is in the courtroom, then the CPU 21 determines whether or not a key operation for changing the focal length in the optical lens unit 11 is performed by operating the zoom key of the key operation unit 24 (step) S106). If it is determined here that the zoom key has not been operated, the processing returns to step S101.

  In this way, the processes of steps S101 to S106 are repeatedly executed, a through image is displayed while executing the focus control by the multi-AF function, and the process waits for the shutter release key to be pressed halfway or the zoom key to be operated.

  When the zoom key is operated, the CPU 21 having determined that in step S106 moves the zoom lens position of the optical lens unit 11 by the lens driving unit 25 and the lens DC motor 29 in accordance with the operated content, and the optical lens unit. 11 is variably set (step S107), and the process returns to step S101.

  In addition, when the shutter release key of the key operation unit 24 is half-pressed during the standby time when the through image is displayed, the CPU 21 determines that in step S105 and determines the AF state and AE set at that time. The shutter speed and aperture value of the process are locked (step S108).

  In this AF and AE locked state, the CPU 21 further determines whether or not the shutter release key has been fully pressed (step S109). It is judged whether it is (step S110).

  Here, if the half-pressing operation of the shutter release key is maintained, the process returns to step S109.

  By repeatedly executing steps S109 and S110 in this way, the CPU 21 waits until the half-pressing operation is performed or the half-pressing operation is released while the shutter release key is half-pressed.

  When the half-press operation of the shutter release key is released, the CPU 21 determines that in step S110, and after releasing the AF state and the shutter speed and aperture value of the AE process that have been locked so far (step S111). Then, in order to wait for the shutter release key to be half-pressed again, the process returns to step S101.

  If the shutter release key is fully pressed, the CPU 21 determines in step S109 and executes a shooting operation under shooting conditions including the AF and AE conditions locked at that time (step S112). .

  Under the control of the CPU 21, the image processing unit 15 creates an image data file in which image data obtained by shooting is compressed for recording, and the created image data file is stored in the memory card via the system bus SB and the memory card controller 28. 31 is recorded (step S113), and the process relating to the shooting and recording of a series of still images is temporarily ended, and the process returns to step S101 to prepare for the next shooting.

  As described above in detail, according to the present embodiment, by taking into account the shift of the focusing distance that varies depending on the position of the photographing optical system in the photographing screen, which is different for each digital camera 10, The multi AF function can be executed accurately.

  In particular, in the above-described embodiment, the optical lens unit 11 includes a zoom lens and an aperture stop that move the focal length, and the focus distance shift is determined in consideration of the focal length of the zoom lens and the aperture value of the aperture stop. Since the correction is made, the multi-AF function can be executed more accurately in consideration of the change in the depth of field.

  In the above embodiment, the focus area used in the multi-AF function is formed by a total of nine frames of 3 × 3 in the approximate center of the shooting screen as shown in FIGS. 2, 3, and 5, for example. However, the present invention is not limited to this, and can be applied to a larger number of focus areas. For example, even in the present situation, some higher-end single-lens reflex digital cameras have a focus area of about 20 to 30 points, and the present invention can be similarly applied to such digital cameras. .

  In the interchangeable lens camera system, the number and arrangement of multi-AF areas differ depending on the model on the camera body side. Therefore, while the interchangeable lens side stores data that maps the amount of shift of the in-focus distance to the lens mount position as a distribution in the shooting screen for each focal length and aperture value, the camera body stores the image sensor from the lens mount position. Is stored for each focus area. In the camera body, the device itself stores it by calculating the amount of deviation corresponding to the focus area position of the camera from the data map stored in the attached interchangeable lens, for example, by performing interpolation calculation if necessary. The amount of in-focus distance from the lens mount position to the image sensor is added to each focus area, and as a result, the in-focus distance is deviated for each focus area from the taking optical system lens to the image sensor. The amount can be acquired.

  In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiment includes various stages, and various inventions can be extracted by an appropriate combination of a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the embodiment, if an effect is obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

The invention described in the claims of the present application of the present application will be appended below.
According to a first aspect of the present invention, there is provided a photographic lens optical system including a focus lens that moves a focus position, an imaging element that outputs an image signal by irradiating an imaging surface with a subject image obtained from the photographic lens optical system, and A focusing error storage unit that stores in advance a focusing error from a focusing state at a reference position at the time of shooting a subject image at an equal distance for each of a plurality of positions in a subject image irradiated on the imaging surface; Focus determination means for determining the respective focus positions of a plurality of positions in the subject image irradiated on the surface, and the determination result of the focus determination means is corrected based on the contents stored in the focus error storage means. And a focusing control unit that determines a moving position of the focus lens of the photographing lens optical system based on a determination result of the focusing determination unit corrected by the correction unit.

  According to a second aspect of the present invention, in the first aspect of the present invention, the photographing lens optical system includes a zoom lens that moves a focal length and an aperture stop, and the focusing error storage means includes a plurality of zoom error lenses. A focusing error is stored in advance for each of a plurality of positions in a subject image irradiated on the imaging surface in accordance with a focal length of the zoom lens and a plurality of aperture values by the aperture stop, and the zoom lens of the photographing lens optical system Detection means for detecting a focal length and an aperture value of the aperture stop is further provided, and the correction means uses the focal length of the zoom lens and the aperture value of the aperture stop detected by the detection means, and the focusing error storage means. And the determination result by the focus determination means is corrected.

  According to a third aspect of the present invention, there is provided a photographic lens optical system including a focus lens that moves a focus position, and an imaging element that outputs an image signal by irradiating an imaging surface with a subject image obtained from the photographic lens optical system. An imaging method using the apparatus, which stores in advance an in-focus error with respect to a focus state at a reference position at the time of subject image shooting at an equal distance for each of a plurality of positions in the subject image irradiated on the imaging surface. Based on the contents stored in the focus error storage step, the focus determination step of determining each focus position of a plurality of positions in the subject image irradiated on the imaging surface, and the content stored in the focus error storage step A correction step for correcting the determination result in the focus determination step, and a focus for determining the movement position of the focus lens of the photographing lens optical system based on the determination result in the focus determination step corrected in the correction step. Having a control process And features.

  According to a fourth aspect of the present invention, there is provided a photographing lens optical system including a focus lens that moves a focus position, and an imaging element that outputs an image signal by irradiating an imaging surface with a subject image obtained from the photographing lens optical system. A program executed by a computer incorporated in the apparatus, wherein the computer is focused at a reference position at the time of subject image photography at an equal distance for each of a plurality of positions in a subject image irradiated on the imaging surface. Focusing error storage means for preliminarily storing a focusing error with respect to the focusing surface, focusing determination means for determining each in-focus position of a plurality of positions in the subject image irradiated on the imaging surface, and the focusing error storage means Correction means for correcting the determination result of the focus determination means based on the contents stored in the above, and the focus lens of the photographing lens optical system based on the determination result of the focus determination means corrected by the correction means Characterized in that to function as an in-focus control means for determining a moving position.

  DESCRIPTION OF SYMBOLS 10 ... Digital camera, 11 ... Optical lens unit, 12 ... CMOS image sensor, 13 ... AGC / A / D conversion part, 14 ... Buffer memory, 15 ... Image processing part, 16 ... Display part, 17 ... Touch panel part, 18 ... Microphone, 19 ... Audio processing unit, 20 ... Speaker, 21 ... CPU, 22 ... Main memory, 23 ... Program memory, 24 ... Key operation unit, 25 ... Lens drive unit, 26 ... Flash drive unit, 27 ... Image sensor (IS ) Drive unit, 28... Memory card controller, 29. Lens DC motor (M), 30. Flash unit, 31. Memory card, 32. Card connector, SB.

Claims (4)

A taking lens optical system including a focus lens for moving the in-focus position;
An image sensor that outputs an image signal by irradiating an imaging surface with a subject image obtained from the photographing lens optical system;
A focus error storage means for storing in advance a focus error with a focus state at a reference position at the time of subject image shooting at an equal distance for each of a plurality of positions in the subject image irradiated on the imaging surface;
In-focus determination means for determining in-focus positions of a plurality of positions in the subject image irradiated on the imaging surface;
Correction means for correcting the determination result of the focus determination means based on the content stored in the focus error storage means;
An imaging apparatus comprising: a focusing control unit that determines a movement position of a focus lens of the photographing lens optical system based on a determination result of the focusing determination unit corrected by the correction unit. The photographing lens optical system includes a zoom lens that moves a focal length and an aperture stop,
The focusing error storage means stores a focusing error for each of a plurality of positions in a subject image irradiated on the imaging surface in accordance with a plurality of focal lengths by the zoom lens and a plurality of aperture values by the aperture stop. Remember in advance,
Further comprising detection means for detecting the focal length of the zoom lens of the photographic lens optical system and the aperture value of the aperture stop,
The correction means refers to the focus error storage means using the focal length of the zoom lens and the aperture value of the aperture stop detected by the detection means, and corrects the determination result by the focus determination means. The imaging apparatus according to claim 1, wherein: An imaging method using an imaging lens optical system including a focus lens that moves a focus position, and an imaging device that outputs an image signal by irradiating an imaging surface with a subject image obtained from the imaging lens optical system. ,
A focus error storing step for storing in advance a focus error with a focus state at a reference position at the time of photographing a subject image at an equal distance for each of a plurality of positions in the subject image irradiated on the imaging surface; ,
An in-focus determination step of determining in-focus positions at a plurality of positions in the subject image irradiated on the imaging surface;
A correction step of correcting the determination result in the focus determination step based on the content stored in the focus error storage step;
An imaging method comprising: a focus control step of determining a movement position of the focus lens of the photographing lens optical system based on the determination result of the focus determination step corrected in the correction step. This is executed by a computer built in a photographing lens optical system including a focus lens that moves a focusing position, and an apparatus having an imaging element that outputs an image signal by irradiating an imaging surface with a subject image obtained from the photographing lens optical system. A program,
The computer
A focus error storage unit that stores in advance a focus error with a focus state at a reference position at the time of subject image photographing at an equal distance for each of a plurality of positions in the subject image irradiated on the imaging surface;
In-focus determination means for determining each in-focus position of a plurality of positions in the subject image irradiated on the imaging surface;
Correction means for correcting the determination result of the focus determination means based on the content stored in the focus error storage means, and the photographing lens optical system based on the determination result of the focus determination means corrected by the correction means A program which functions as a focusing control means for determining the moving position of the focus lens.

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