WO2013145887A1

WO2013145887A1 - Imaging device and imaging method

Info

Publication number: WO2013145887A1
Application number: PCT/JP2013/053034
Authority: WO
Inventors: 貴嗣青木
Original assignee: 富士フイルム株式会社
Priority date: 2012-03-28
Filing date: 2013-02-08
Publication date: 2013-10-03

Abstract

A solid-state imaging element (5) is provided with pixel cells (30) for imaging and pixel cells (31R, 31L) for focus detection. While in a continuous shooting mode, a defocus amount is calculated between an exposure (1) and an exposure (2) of the imaging element (5) using the imaging signals of the pixel cells (31R, 31L) for focus detection that are included in the captured image signal obtained using the exposure (1), and focusing adjustment of a focus lens included in an imaging lens (1) is begun on the basis of the defocus amount.

Description

Imaging apparatus and imaging method

The present invention relates to an imaging apparatus and an imaging method.

In recent years, with the increase in the resolution of solid-state imaging devices such as CCD (Charge Coupled Device) image sensors and CMOS (Complementary Metal Oxide Semiconductor) image sensors, digital still cameras, digital video cameras, mobile phones, PDA (Personal DigitalAssessment). The demand for information equipment having a photographing function such as an information terminal is rapidly increasing. Note that an information device having the above imaging function is referred to as an imaging device.

By the way, there are a contrast AF (Auto Focus) method and a phase difference AF method as a focus control method for focusing on a main subject. Since the phase difference AF method can detect the in-focus position at a higher speed and with higher accuracy than the contrast AF method, the phase difference AF method is widely used in various imaging apparatuses (see, for example, Patent Document 1).

The phase difference AF method detects the phase difference based on the image signal of the subject image output from the image sensor, and adjusts the focus of the focus lens based on the detected phase difference.

Patent Document 1 describes a method that enables high-speed continuous shooting in an imaging apparatus that employs the phase difference AF method.

Specifically, Patent Document 1 stores a focus detection signal output from a focus detection pixel cell at the time of shooting in a memory, determines whether or not the current shooting is a continuous shooting following the previous shooting, and continues. A technique is disclosed in which, when it is determined that shooting is performed, a focus detection signal at the time of previous shooting recorded in a memory is read, and focus adjustment for the current shooting is performed by phase difference AF using the focus detection signal. .

Japanese Unexamined Patent Publication No. 2008-310072

However, the technique described in Patent Document 1 detects the phase difference based on the focus detection signal at the time of the first image read from the memory after the first image is captured, and the subsequent imaging optical system. Since focus adjustment is performed and then the second image is started, the time interval from the end of the first image to the start of the second image is long, and there is a limit to increasing the continuous shooting speed.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an imaging apparatus and an imaging method capable of performing continuous imaging at high speed using the phase difference AF method.

In the imaging device of the present invention, a plurality of imaging pixel cells and a plurality of types of focus detection pixel cells that receive light beams that have passed through different portions of the pupil region of the imaging optical system including the focus lens are arranged on a plane. Imaging optics based on the phase difference between a solid-state image sensor that receives an image formed by the imaging optical system and outputs a captured image signal, and a pair of focus detection signals output from a plurality of types of focus detection pixel cells In a mode in which a focus detection unit that calculates the defocus amount of the system and a focus adjustment unit that adjusts the focus of the photographing optical system by moving the focus lens based on the defocus amount, In the imaging period from the start of the first exposure of the solid-state imaging device to the end of reading of the captured image signal obtained by the first exposure from the solid-state imaging device, the focus detection unit performs the first exposure. The defocus amount is calculated based on the phase difference between the pair of focus detection signals included in the captured image signal obtained by the previous exposure, and the focus adjustment unit adjusts the focus of the photographing optical system based on the calculated defocus amount. It is what is started.

According to the imaging method of the present invention, a plurality of imaging pixel cells and a plurality of focus detection pixel cells that receive a pair of light beams that have passed through different parts of the pupil region of the imaging optical system including the focus lens are arranged on a plane. An imaging method using an imaging apparatus having a solid-state imaging device that receives an image formed by a photographing optical system and outputs a captured image signal, and in a mode in which shooting is continuously performed, In the imaging period from the start of exposure to the end of readout of the imaged image signal obtained by the first exposure from the solid-state imaging device, a plurality of images included in the imaged image signal obtained by the exposure before the first exposure The defocus amount is calculated based on the phase difference between the pair of focus detection signals corresponding to the pair of light beams output from the focus detection pixel cell, and the focus is determined based on the calculated defocus amount. It is to start the focus adjustment of the photographing optical system by moving the lens.

According to the present invention, it is possible to provide an imaging apparatus and an imaging method capable of performing continuous imaging at high speed using the phase difference AF method.

It is a schematic block diagram of the digital camera which is an example of the imaging device of this invention. It is a top view which shows schematic structure of the solid-state image sensor mounted in the digital camera shown in FIG. 3 is a flowchart illustrating an example of a shooting operation of the digital camera 1 illustrated in FIG. 1. 6 is a flowchart illustrating another example of the photographing operation of the digital camera 1 illustrated in FIG. 1. 6 is a flowchart illustrating another example of the photographing operation of the digital camera 1 illustrated in FIG. 1. 6 is a flowchart illustrating another example of the photographing operation of the digital camera 1 illustrated in FIG. 1. It is a figure explaining a smart phone as an imaging device. It is an internal block diagram of the smart phone of FIG.

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

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a digital camera as an example of an imaging apparatus for explaining the first embodiment of the present invention.

The imaging system of the digital camera shown in FIG. 1 includes a photographic lens 1 as a photographic optical system, a solid-state imaging device 5 such as a CCD image sensor or a CMOS image sensor, an aperture 2 provided between the two, and an infrared cut. A filter (IRCUT) 3 and an optical low-pass filter (OLPF) 4 are provided.

The solid-state imaging device 5 has a configuration in which a plurality of imaging pixel cells and a plurality of types of focus detection pixel cells that receive light beams that have passed through different portions of the pupil region of the photographing optical system are arranged two-dimensionally. The image formed by the photographing lens 1 is received and a picked-up image signal is output, and a pair of focus detection signals corresponding to the light flux are output.

The system control unit 11 that controls the entire electric control system of the digital camera controls the flash light emitting unit 12 and the light receiving unit 13. Further, the system control unit 11 controls the lens driving unit 8 to adjust the position of the focus lens included in the photographing lens 1 or adjust the position of the zoom lens included in the photographing lens 1. Further, the system control unit 11 adjusts the exposure amount by controlling the aperture amount of the aperture 2 via the aperture drive unit 9.

Further, the system control unit 11 drives the solid-state imaging device 5 via the imaging device driving unit 10 and outputs a subject image captured through the photographing lens 1 as a captured image signal. An instruction signal from the user is input to the system control unit 11 through the operation unit 14.

The electrical control system of the digital camera further includes an analog signal processing unit 6 that performs analog signal processing such as correlated double sampling processing connected to the output of the solid-state imaging device 5, and RGB output from the analog signal processing unit 6. And an A / D conversion circuit 7 for converting the color signal into a digital signal. The analog signal processing unit 6 and the A / D conversion circuit 7 are controlled by the system control unit 11.

Further, the electric control system of the digital camera performs main memory 16, a memory control unit 15 connected to the main memory 16, interpolation calculation, gamma correction calculation, RGB / YC conversion processing, etc. A digital signal processing unit 17 to be generated, a compression / decompression processing unit 18 that compresses the captured image data generated by the digital signal processing unit 17 into a JPEG format or expands the compressed image data, and focus detection of the solid-state imaging device 5 A focus detection unit 19 that calculates a defocus amount of the photographing lens 1 based on a phase difference between a pair of focus detection signals output from the pixel cell, and an external memory control unit 20 to which a detachable recording medium 21 is connected. And a display control unit 22 to which a display unit 23 mounted on the rear surface of the camera or the like is connected. The memory control unit 15, digital signal processing unit 17, compression / decompression processing unit 18, focus detection unit 19, external memory control unit 20, and display control unit 22 are mutually connected by a control bus 24 and a data bus 25, and system control is performed. It is controlled by a command from the unit 11.

FIG. 2 is a schematic plan view showing a schematic configuration of the solid-state imaging device 5 mounted on the digital camera shown in FIG.

The solid-state imaging device 5 includes a large number of pixel cells (each square in the drawing) arranged in a two-dimensional manner (in the example of FIG. 2, a square lattice shape) in the row direction X and the column direction Y orthogonal thereto. . A large number of pixel cells are arranged such that pixel cell rows composed of a plurality of pixel cells arranged at a constant pitch in the row direction X are arranged at a constant pitch in the column direction Y. The many pixel cells include an imaging pixel cell 30, a focus detection pixel cell 31L, and a focus detection pixel cell 31R.

The imaging pixel cell 30 has both a pair of lights that have passed through different portions of the pupil region of the photographing lens 1 shown in FIG. Is a pixel cell that receives light.

The focus detection pixel cell 31L is a pixel cell that receives one of the pair of lights. Compared with the imaging pixel cell 30, the opening (region not hatched) of the photoelectric conversion unit is eccentric to the left side. It has a configuration.

The focus detection pixel cell 31 </ b> R is a pixel cell that receives the other of the pair of lights. Compared with the imaging pixel cell 30, the opening of the photoelectric conversion unit (a region not hatched) is decentered to the right side. It has a configuration.

A color filter is mounted above the photoelectric conversion unit included in each of the pixel cells, and the array of the color filters is a Bayer array over the entire number of pixel cells constituting the solid-state imaging device 5.

In FIG. 2, “R” is written in the pixel cell on which the color filter that transmits red (R) light is mounted. In addition, “G” is written in a pixel cell on which a color filter that transmits green (G) light is mounted. Further, “B” is written in the pixel cell on which the color filter that transmits blue (B) light is mounted. In the example of FIG. 2, the solid-state imaging device 5 is equipped with a color filter, but it may be one without a color filter.

The focus detection pixel cells 31L are arranged at intervals of three pixel cells in the third pixel cell row from the top of FIG. 2 at the positions of pixel cells on which a color filter that transmits green (G) light is mounted.

In the fifth pixel cell row from the top in FIG. 2, the focus difference detection pixel cell 31R is arranged at every third pixel cell at the position of the pixel cell on which the color filter that transmits green (G) light is mounted. .

The focus detection pixel cell 31L and the focus detection pixel cell 31R at the same position in the row direction X form a pair, and the solid-state imaging device 5 has a configuration in which a plurality of pairs are provided.

The focus detection unit 19 shown in FIG. 1 uses a group of signals read from the focus detection pixel cell 31L and the focus detection pixel cell 31R and uses the signal group read out from the focus detection pixel cell 31R. And its direction, that is, the defocus amount is calculated.

The system control unit 11 illustrated in FIG. 1 performs focus adjustment by controlling the position of the focus lens included in the imaging lens 1 based on the defocus amount calculated by the focus detection unit 19.

FIG. 3 is a timing chart for explaining the photographing operation of the digital camera shown in FIG. Here, illustration and description of camera operations not directly related to the present invention are omitted.

In a continuous shooting mode in which shooting for recording is continuously performed, when a shooting start signal from a user is input to the system control unit 11 through the operation unit 14, the system control unit 11 performs one sheet via the image sensor driving unit 10. Eye exposure (photographing exposure (1)) is started.

When the photographic exposure (1) is completed, the system control unit 11 performs driving for reading out the captured image signal from the solid-state image sensor 5 via the image sensor driving unit 10, and stores the captured image signal in the main memory 16 (signal). Uptake (1)). When the signal capture (1) is completed, the digital signal processing unit 17 processes the captured image signal stored in the main memory 16, generates captured image data, and records the generated captured image data in the recording medium 21. .

When the signal capture (1) is completed, the system control unit 11 starts the second exposure (shooting exposure (2)) via the image sensor driving unit 10.

When the photographic exposure (2) is completed, the system control unit 11 performs driving for reading out the captured image signal from the solid-state image sensor 5 via the image sensor driving unit 10, and stores the captured image signal in the main memory 16 (signal). Uptake (2)). When the signal capture (2) is completed, the digital signal processing unit 17 processes the captured image signal stored in the main memory 16, generates captured image data, and records the generated captured image data in the recording medium 21. .

After the completion of the signal capture (2), the third exposure (photographing exposure (3)), capture of the captured image signal obtained by the photographing exposure (3) (signal capture (3)), The exposure of the first sheet (photographing exposure (4)) and the capture of the captured image signal (signal capture (4)) obtained by the photographing exposure (4) are sequentially performed.

The system control unit 11 repeatedly performs shooting exposure and signal capture control for a preset number of times in the continuous shooting mode.

When the signal capture (1) ends, the focus detection unit 19 acquires the captured image signal stored in the main memory 16 by the signal capture (1), and among the captured image signals, focus

detection pixel cells

31L and 31R. A pair of focus detection signals output from the image are subjected to correlation calculation to detect a phase difference (image shift amount), and AF calculation is performed to calculate a defocus amount based on the phase difference (AF calculation (1) in FIG. 3). ).

When the AF calculation (1) ends, the system control unit 11 controls the lens driving unit 8 based on the defocus amount calculated by the AF calculation (1), and drives the photographing lens 1 to adjust the focus. (Lens drive (1) in FIG. 3).

The AF calculation (1) and the lens driving (1) are started in a period in which the photographing exposure (2) and the signal capture (2) are performed, respectively.

When the signal capture (2) is completed, the focus detection unit 19 acquires the captured image signal stored in the main memory 16 by the signal capture (2), and among the captured image signals, focus

detection pixel cells

31L and 31R. The pair of focus detection signals output from the signal are subjected to correlation calculation to detect a phase difference, and AF calculation for calculating a defocus amount based on the phase difference is performed (AF calculation (2) in FIG. 3).

When the AF calculation (2) is completed, the system control unit 11 controls the lens driving unit 8 based on the defocus amount calculated by the AF calculation (2), and drives the photographing lens 1 to adjust its focus. (Lens drive (2) in FIG. 3).

The AF calculation (2) and the lens driving (2) are started in a period in which the photographing exposure (3) and the signal capture (3) are performed, respectively.

When the signal capture (3) is completed, the focus detection unit 19 acquires the captured image signal stored in the main memory 16 by the signal capture (3), and among the captured image signals, focus

detection pixel cells

31L and 31R. A pair of focus detection signals output from the CPU are correlated to detect a phase difference, and an AF calculation is performed to calculate a defocus amount based on the phase difference (AF calculation (3) in FIG. 3).

When the AF calculation (3) is completed, the system control unit 11 controls the lens driving unit 8 based on the defocus amount calculated by the AF calculation (3), and drives the photographing lens 1 to adjust its focus. (Lens drive (3) in FIG. 3).

The AF calculation (3) and the lens driving (3) are started in a period in which the photographing exposure (4) and the signal capture (4) are performed, respectively.

As described above, the digital camera according to the present embodiment performs the previous exposure (shooting exposure N-1) during the exposure (shooting exposure N) and the captured image signal obtained thereby (signal capture N). Since the calculation of the defocus amount based on the obtained focus detection signal (AF calculation N-1) and the subsequent focus adjustment of the photographing lens 1 (lens driving N-1) are performed, continuous photographing using the phase difference AF method is performed. It can be done at high speed.

In the present embodiment, the photographic exposure (1) and the photographic exposure (2) are performed in a state where the focus is not achieved, and the focus is achieved from the third and subsequent exposures. However, in continuous shooting mode in which shooting is performed continuously, many exposures are performed in a short time, so there is no problem even if the first two shots are not in focus, and it is possible to shoot at a higher speed than that. Is a big advantage.

In the photographing operation shown in FIG. 3, the focus adjustment (for example, lens driving (1)) of the photographing lens 1 is started before the exposure (for example, photographing exposure (2)) ends. Since the focus follows the movement of the subject by adjusting the focus of the photographing lens 1 in advance, an image with natural movement is often obtained.

In the shooting operation shown in FIG. 3, the AF calculation is started simultaneously with the start of the shooting exposure, but the AF calculation may be started during the period when the shooting exposure is performed.

As shown in FIG. 3, by starting AF calculation almost simultaneously with the start of shooting exposure, lens driving is performed during exposure (shooting exposure N) and capturing of a captured image signal (signal capturing N) obtained thereby. Can increase the probability of being terminated. As a result, it is possible to prevent the lens from being driven during the next photographing exposure, and to improve the image quality.

Further, in the photographing operation shown in FIG. 3, the lens driving is started simultaneously with the end of the AF calculation, but the lens driving may be started after a predetermined time from the end of the AF calculation.

As shown in FIG. 3, the lens driving is started almost simultaneously with the end of the AF calculation, so that AF (shooting exposure N) and capture of a captured image signal (signal capture N) obtained thereby are performed during AF. The probability that calculation and lens driving can be finished can be increased. As a result, it is possible to prevent the lens from being driven during the next photographing exposure, and to improve the image quality.

(Second embodiment)
FIG. 4 is a timing chart showing another example of the photographing operation of the digital camera shown in FIG. Only the differences from the first embodiment will be described here.

In the present embodiment, as shown in FIG. 4, the lens driving ((1), (2), (3)) is started after the end of each exposure ((2), (3), (4)). Different from the first embodiment. In FIG. 4, the start of lens driving is coincident with the start of signal capture, but this may not be coincident.

According to the present embodiment, since the focus lens does not move during photographing exposure, it is possible to suppress a focus shift. Therefore, for example, when continuously shooting a subject that does not move, such as a landscape, it is effective to shoot in such an operation mode.

(Third embodiment)
FIG. 5 is a timing chart showing another example of the photographing operation of the digital camera shown in FIG. Only the differences from the first embodiment will be described here.

3 and 4, for example, when the focal length of the subject changes greatly during shooting exposure (2) and the time required for lens driving (2) becomes longer, for example, shooting exposure (4) and lens driving (2). May overlap.

Therefore, in the digital camera of this embodiment, as shown in FIG. 5, the lens drive (N) (lens drive (1) in the example of FIG. 5) is the next exposure (N + 2) (shooting in the example of FIG. 5). In the case where it does not end before the start of exposure (3)), the system control unit 11 limits the end timing of lens driving (1) with the start timing of shooting exposure (3).

That is, the lens driving (1) is forcibly terminated at the start timing of the photographing exposure (3). By such control, even when the time required for driving the lens becomes long, it is possible to prevent the focus lens from moving during the photographing exposure, and thus it is possible to suppress a shift in focus.

Even when the lens drive (N) end timing is not limited by the shooting exposure (N + 2) start timing, when shooting an object that continues to move, the focus will follow the movement of the object, which is a major disadvantage. Must not.

For example, when the moving direction of the focus lens according to the defocus amount obtained by the AF calculation (1) is the same as the moving direction of the focus lens according to the defocus amount obtained by the AF calculation (2) It can be determined that the subject continues to move from the start of shooting exposure (1) to the start of shooting exposure (3).

As described above, when the subject continues to move, the influence on the image quality is limited even if the end timing of the lens drive (2) is not limited.

Therefore, when the system control unit 11 determines that the subject continues to move in a certain direction after the start of continuous shooting, it is preferable not to limit the end timing of the lens drive (N). .

Specifically, after performing the AF calculation (N), the system control unit 11 determines that the movement direction of the focus lens determined by the AF calculation (N) is the movement of the focus lens in the immediately preceding lens drive (N−1). When the direction is the same, the end timing is not limited in lens driving (N).

On the other hand, the system control unit 11 performs the AF calculation (N), and then the moving direction of the focus lens determined by the AF calculation (N) is different from the moving direction of the focus lens in the lens driving (N−1) immediately before that. In the case of N = 1, the end timing is limited in lens driving (N).

For example, as shown in FIG. 6, the system control unit 11 limits the end timing for the lens drive (1), and the focus lens of the focus lens determined by the moving direction of the focus lens in the lens drive (1) and the AF calculation (2). When the movement direction matches, the end timing of the lens drive (2) is not limited.

Such control makes it possible to perform AF following a moving subject and improve the quality of continuous shot images.

(Fourth embodiment)
In this embodiment, a configuration of a smartphone as an imaging device will be described.

FIG. 7 shows an appearance of a smartphone 200 that is an embodiment of the photographing apparatus of the present invention. A smartphone 200 illustrated in FIG. 7 includes a flat housing 201, and a display input in which a display panel 202 as a display unit and an operation panel 203 as an input unit are integrated on one surface of the housing 201. Part 204 is provided. Such a housing 201 includes a speaker 205, a microphone 206, an operation unit 207, and a camera unit 208. Note that the configuration of the housing 201 is not limited thereto, and for example, a configuration in which the display unit and the input unit are independent can be employed, or a configuration having a folding structure and a slide mechanism can be employed.

FIG. 8 is a block diagram showing a configuration of the smartphone 200 shown in FIG. As shown in FIG. 7, the main components of the smartphone include a wireless communication unit 210, a display input unit 204, a call unit 211, an operation unit 207, a camera unit 208, a storage unit 212, and an external input / output unit. 213, a GPS (Global Positioning System) receiving unit 214, a motion sensor unit 215, a power supply unit 216, and a main control unit 220. As a main function of the smartphone 200, a wireless communication function for performing mobile wireless communication via a base station device BS (not shown) and a mobile communication network NW (not shown) is provided.

The wireless communication unit 210 performs wireless communication with the base station apparatus BS accommodated in the mobile communication network NW according to an instruction from the main control unit 220. Using this wireless communication, transmission and reception of various file data such as audio data and image data, e-mail data, and reception of Web data and streaming data are performed.

The display input unit 204 controls the main control unit 220 to display images (still images and moving images), character information, and the like to visually transmit information to the user and to detect user operations on the displayed information. A so-called touch panel, which includes a display panel 202 and an operation panel 203.

The display panel 202 uses an LCD (Liquid Crystal Display), an OELD (Organic Electro-Luminescence Display), or the like as a display device.

The operation panel 203 is a device that is placed so that an image displayed on the display surface of the display panel 202 is visible and detects one or more coordinates operated by a user's finger or stylus. When this device is operated with a user's finger or stylus, a detection signal generated due to the operation is output to the main control unit 220. Next, the main control unit 220 detects an operation position (coordinates) on the display panel 202 based on the received detection signal.

As shown in FIG. 7, the display panel 202 and the operation panel 203 of the smartphone 200 exemplified as an embodiment of the photographing apparatus of the present invention integrally constitute a display input unit 204. The arrangement 203 covers the display panel 202 completely.

When such an arrangement is adopted, the operation panel 203 may have a function of detecting a user operation even in an area outside the display panel 202. In other words, the operation panel 203 includes a detection area (hereinafter referred to as a display area) for an overlapping portion that overlaps the display panel 202 and a detection area (hereinafter, a non-display area) for an outer edge portion that does not overlap the other display panel 202. May be included).

Although the size of the display area and the size of the display panel 202 may be completely matched, it is not always necessary to match the two. In addition, the operation panel 203 may include two sensitive areas of the outer edge portion and the other inner portion. Further, the width of the outer edge portion is appropriately designed according to the size of the housing 201 and the like. Furthermore, examples of the position detection method employed in the operation panel 203 include a matrix switch method, a resistance film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, a capacitance method, and the like. You can also

The call unit 211 includes a speaker 205 and a microphone 206, converts user's voice input through the microphone 206 into voice data that can be processed by the main control unit 220, and outputs the voice data to the main control unit 220. 210 or the audio data received by the external input / output unit 213 is decoded and output from the speaker 205. As shown in FIG. 7, for example, the speaker 205 can be mounted on the same surface as the display input unit 204 and the microphone 206 can be mounted on the side surface of the housing 201.

The operation unit 207 is a hardware key using a key switch or the like, and receives an instruction from the user. For example, as illustrated in FIG. 7, the operation unit 207 is mounted on the side surface of the housing 201 of the smartphone 200 and is turned on when pressed with a finger or the like, and is turned off by a restoring force such as a spring when the finger is released. It is a push button type switch.

The storage unit 212 includes a control program and control data of the main control unit 220, application software, address data that associates the name and telephone number of a communication partner, transmitted / received e-mail data, Web data downloaded by Web browsing, The downloaded content data is stored, and streaming data and the like are temporarily stored. The storage unit 212 includes an internal storage unit 217 built in the smartphone and an external storage unit 218 having a removable external memory slot. Each of the internal storage unit 217 and the external storage unit 218 constituting the storage unit 212 includes a flash memory type (hard memory type), a hard disk type (hard disk type), a multimedia card micro type (multimedia card micro type), This is realized using a storage medium such as a card type memory (for example, MicroSD (registered trademark) memory), a RAM (Random Access Memory), a ROM (Read Only Memory), or the like.

The external input / output unit 213 serves as an interface with all external devices connected to the smartphone 200, and communicates with other external devices (for example, universal serial bus (USB), IEEE 1394, etc.) or a network. (For example, Internet, wireless LAN, Bluetooth (registered trademark), RFID (Radio Frequency Identification), Infrared Data Association (IrDA) (registered trademark), UWB (Ultra Wideband) (registered trademark) ZigBee) (registered trademark, etc.) for direct or indirect connection.

As an external device connected to the smartphone 200, for example, a wired / wireless headset, a wired / wireless external charger, a wired / wireless data port, a memory card (Memory card) connected via a card socket, or a SIM (Subscriber). Identity Module Card / UIM (User Identity Module Card) card, external audio / video equipment connected via audio / video I / O (Input / Output) terminal, external audio / video equipment connected wirelessly, yes / no There are a wirelessly connected smartphone, a wired / wireless personal computer, a wired / wireless PDA, a wired / wireless personal computer, an earphone, and the like. The external input / output unit 213 transmits data received from such an external device to each component inside the smartphone 200, or allows the data inside the smartphone 200 to be transmitted to the external device. Can do.

The GPS receiving unit 214 receives GPS signals transmitted from the GPS satellites ST1 to STn in accordance with instructions from the main control unit 220, executes positioning calculation processing based on the received GPS signals, and calculates the latitude of the smartphone 200 Detect the position consisting of longitude and altitude. When the GPS reception unit 214 can acquire position information from the wireless communication unit 210 or the external input / output unit 213 (for example, a wireless LAN), the GPS reception unit 214 can also detect the position using the position information.

The motion sensor unit 215 includes, for example, a three-axis acceleration sensor, and detects the physical movement of the smartphone 200 in accordance with an instruction from the main control unit 220. By detecting the physical movement of the smartphone 200, the moving direction and acceleration of the smartphone 200 are detected. The detection result is output to the main control unit 220.

The power supply unit 216 supplies power stored in a battery (not shown) to each unit of the smartphone 200 in accordance with an instruction from the main control unit 220.

The main control unit 220 includes a microprocessor, operates according to a control program and control data stored in the storage unit 212, and controls each unit of the smartphone 200 in an integrated manner. In addition, the main control unit 220 includes a mobile communication control function that controls each unit of the communication system and an application processing function in order to perform voice communication and data communication through the wireless communication unit 210.

The application processing function is realized by the main control unit 220 operating according to the application software stored in the storage unit 212. Examples of the application processing function include an infrared communication function for controlling the external input / output unit 213 to perform data communication with the opposite device, an e-mail function for transmitting / receiving e-mails, and a web browsing function for browsing web pages. .

Also, the main control unit 220 has an image processing function such as displaying video on the display input unit 204 based on image data (still image or moving image data) such as received data or downloaded streaming data. The image processing function is a function in which the main control unit 220 decodes the image data, performs image processing on the decoding result, and displays an image on the display input unit 204.

Further, the main control unit 220 executes display control for the display panel 202 and operation detection control for detecting a user operation through the operation unit 207 and the operation panel 203. By executing the display control, the main control unit 220 displays an icon for starting application software, a software key such as a scroll bar, or a window for creating an e-mail. Note that the scroll bar refers to a software key for accepting an instruction to move the display portion of a large image that does not fit in the display area of the display panel 202.

In addition, by executing the operation detection control, the main control unit 220 detects a user operation through the operation unit 207 or accepts an operation on the icon or an input of a character string in the input field of the window through the operation panel 203. Or a display image scroll request through a scroll bar.

Further, by executing the operation detection control, the main control unit 220 causes the operation position with respect to the operation panel 203 to overlap with the display panel 202 (display area) or other outer edge part (non-display area) that does not overlap with the display panel 202. And a touch panel control function for controlling the sensitive area of the operation panel 203 and the display position of the software key.

The main control unit 220 can also detect a gesture operation on the operation panel 203 and execute a preset function in accordance with the detected gesture operation. Gesture operation is not a conventional simple touch operation, but an operation that draws a trajectory with a finger or the like, designates a plurality of positions at the same time, or combines these to draw a trajectory for at least one of a plurality of positions. means.

The camera unit 208 includes configurations other than the external memory control unit 20, the recording medium 21, the display control unit 22, the display unit 23, and the operation unit 14 in the digital camera shown in FIG. The captured image data generated by the camera unit 208 can be recorded in the storage unit 212 or output through the input / output unit 213 or the wireless communication unit 210. In the smartphone 200 shown in FIG. 7, the camera unit 208 is mounted on the same surface as the display input unit 204, but the mounting position of the camera unit 208 is not limited to this, and the camera unit 208 may be mounted on the back surface of the display input unit 204. Good.

The camera unit 208 can be used for various functions of the smartphone 200. For example, an image acquired by the camera unit 208 can be displayed on the display panel 202, or the image of the camera unit 208 can be used as one of operation inputs of the operation panel 203. Further, when the GPS receiving unit 214 detects a position, the position can be detected with reference to an image from the camera unit 208. Furthermore, referring to the image from the camera unit 208, the optical axis direction of the camera unit 208 of the smartphone 200 can be determined without using the triaxial acceleration sensor or in combination with the triaxial acceleration sensor. It is also possible to determine the current usage environment. Of course, the image from the camera unit 208 can also be used in the application software.

In addition, the position information acquired by the GPS receiving unit 214 to the image data of the still image or the moving image, the voice information acquired by the microphone 206 (the text information may be converted into voice information by the main control unit or the like), Posture information and the like acquired by the motion sensor unit 215 can be added and recorded in the recording unit 212, or can be output through the input / output unit 213 and the wireless communication unit 210.

Even in the smartphone 200 configured as described above, high-speed continuous shooting using phase difference AF can be performed.

As described above, the following items are disclosed in this specification.

In the disclosed imaging device, a plurality of imaging pixel cells and a plurality of types of focus detection pixel cells that receive light beams that have passed through different portions of the pupil region of the imaging optical system including the focus lens are arranged on a plane. Based on a phase difference between a solid-state image sensor that receives an image formed by the photographing optical system and outputs a captured image signal, and a pair of focus detection signals output from the plurality of types of focus detection pixel cells. A focus detection unit that calculates a defocus amount of the imaging optical system; and a focus adjustment unit that adjusts the focus of the imaging optical system by moving the focus lens based on the defocus amount. In the mode to be performed, from the start of the first exposure of the solid-state imaging device until the reading of the captured image signal obtained by the first exposure from the solid-state imaging device is completed. In the image period, the focus detection unit calculates a defocus amount based on a phase difference between the pair of focus detection signals included in the captured image signal obtained by exposure before the first exposure, and the focus The adjustment unit starts focus adjustment of the photographing optical system based on the calculated defocus amount.

In the disclosed imaging apparatus, the focus adjustment unit starts focus adjustment of the imaging optical system after the first exposure is completed in the imaging period.

The disclosed imaging apparatus performs the focus adjustment when the end timing of the focus adjustment of the imaging optical system that is started in the imaging period is after the start of the second exposure that is performed following the first exposure. A control unit that performs stop control to be terminated at the start timing of the second exposure is provided.

In the disclosed imaging device, the control unit moves the focus lens based on a defocus amount calculated by the focus detection unit during the previous imaging period of two consecutive imaging periods, and the 2 When the movement direction of the focus lens based on the defocus amount calculated by the focus detection unit coincides during the subsequent imaging period among the two imaging periods, the stop control is performed during the subsequent imaging period. There is nothing.

In the disclosed imaging apparatus, the focus detection unit starts calculating the defocus amount during the period in which the first exposure is performed.

In the disclosed imaging apparatus, the focus detection unit starts calculating the defocus amount almost simultaneously with the start of the first exposure.

In the disclosed imaging method, a plurality of imaging pixel cells and a plurality of focus detection pixel cells that receive a pair of light beams that have passed through different portions of the pupil region of the imaging optical system including the focus lens are arranged on a plane. An imaging method using an imaging apparatus having a solid-state imaging device that receives an image formed by the imaging optical system and outputs a captured image signal, wherein the solid-state imaging device The imaging obtained by the exposure before the first exposure during the imaging period from the start of the first exposure until the readout of the captured image signal obtained by the first exposure from the solid-state imaging device is completed. Calculating a defocus amount based on a phase difference between a pair of focus detection signals corresponding to the pair of light fluxes output from the plurality of focus detection pixel cells included in the image signal; By moving the focus lens based on the defocus amount issued is to start the focus adjustment of the photographic optical system.

As mentioned above, although this invention was demonstrated by specific embodiment, this invention is not limited to this embodiment, A various change is possible in the range which does not deviate from the technical idea of the disclosed invention.
This application is based on a Japanese patent application filed on Mar. 28, 2012 (Japanese Patent Application No. 2012-074308), the contents of which are incorporated herein.

DESCRIPTION OF SYMBOLS 1 Shooting lens 5 Solid-state image sensor 30

Imaging pixel cell

31R, 31L Focus detection pixel cell

Claims

A plurality of imaging pixel cells and a plurality of types of focus detection pixel cells that receive light beams that have passed through different portions of the pupil region of the imaging optical system including the focus lens are arranged on a plane and are connected by the imaging optical system. A solid-state image sensor that receives an image to be imaged and outputs a captured image signal;
A focus detection unit that calculates a defocus amount of the imaging optical system based on a phase difference between a pair of focus detection signals output from the plurality of types of focus detection pixel cells;
A focus adjustment unit that adjusts the focus of the photographing optical system by moving the focus lens based on the defocus amount;
In a mode in which shooting is continuously performed, in the imaging period from the start of the first exposure of the solid-state imaging device to the end of reading of the captured image signal obtained by the first exposure from the solid-state imaging device, The focus detection unit calculates a defocus amount based on a phase difference between the pair of focus detection signals included in the captured image signal obtained by exposure before the first exposure, and the focus adjustment unit An imaging apparatus that starts focus adjustment of the imaging optical system based on the calculated defocus amount.
The imaging apparatus according to claim 1,
The focus adjustment unit is an imaging apparatus that starts focus adjustment of the photographing optical system after the first exposure is completed in the imaging period.
The imaging apparatus according to claim 1 or 2,
When the end timing of the focus adjustment of the imaging optical system that is started in the imaging period is after the start of the second exposure that is performed following the first exposure, the focus adjustment is started in the second exposure. An imaging apparatus including a control unit that performs stop control to be terminated at timing.
The imaging apparatus according to claim 3,
The control unit includes a moving direction of the focus lens based on a defocus amount calculated by the focus detection unit during a previous imaging period of two consecutive imaging periods, and a rear of the two imaging periods. An imaging apparatus that does not perform the stop control in the subsequent imaging period when the moving direction of the focus lens matches the movement direction of the focus lens based on the defocus amount calculated by the focus detection unit during the imaging period.
The imaging apparatus according to any one of claims 1 to 4, wherein
The focus detection unit is an imaging apparatus that starts calculating the defocus amount during a period in which the first exposure is performed.
The imaging apparatus according to claim 5, wherein
The focus detection unit is an imaging apparatus that starts calculating the defocus amount substantially simultaneously with the start of the first exposure.
A plurality of imaging pixel cells and a plurality of focus detection pixel cells that receive a pair of light beams that have passed through different portions of the pupil region of the imaging optical system including the focus lens are arranged on a plane, and the imaging optical system An imaging method by an imaging device having a solid-state imaging device that receives an imaged image and outputs a captured image signal,
In the mode in which shooting is performed continuously, during the imaging period from the start of the first exposure of the solid-state imaging device to the end of reading of the captured image signal obtained by the first exposure from the solid-state imaging device, Based on the phase difference between the pair of focus detection signals corresponding to the pair of light fluxes output from the plurality of focus detection pixel cells included in the captured image signal obtained by the exposure before the first exposure. An imaging method for calculating a focus amount, and starting focus adjustment of the imaging optical system by moving the focus lens based on the calculated defocus amount.