WO2021010528A1 - Camera and control method therefor - Google Patents

Abstract

The present invention relates to a camera and a control method therefor, and has a subject matter of obtaining, from an image sensor, phase detection auto focus data (hereinafter referred to as PDAF data) while an auto focus algorithm is performed, and rotating the image sensor at a predetermined angle in a first direction when the reliability of the PDAF data is less than a preset threshold value.

Description

Camera and its control method

The present invention relates to a camera and a control method thereof, and more particularly, to a camera for improving the accuracy of autofocus by rotating an image sensor when the reliability of PDAF data is lower than a preset threshold, and a control method thereof.

With the recent development of IT technology, mobile devices are emerging as a big issue in everyday life. The functions of mobile devices are diversifying. For example, there is a function of taking pictures and taking videos through a camera.

One of the major issues related to mobile devices is how to improve camera functions. The phase difference auto focus (AF) technology, which was mainly used in DSLR cameras, is rapidly being ported to smartphones. Major CMOS image sensor (CIS) companies are releasing new CIS products with phase difference detection function.

Recently, the industry is releasing a CIS with a so-called'Phase Detection Auto Focus (PDAF)' technology.

CIS with built-in PDAF technology is characterized by a significantly faster speed compared to existing products that focus on color contrast. PDAF divides the light coming through the lens into pairs and compares the phase difference to determine whether the focus is correct. DSLR cameras are equipped with a separate AF sensor to check the phase difference of light. This structure was difficult to apply in mobile devices pursuing lightness, thinness, and reduction, but CIS companies solved this problem by embedding a function to detect phase difference in some of the effective pixels of the sensor.

However, in the case of the prior art, when an image contains a large number of horizontal components, there is a problem in that it is difficult to accurately focus due to poor reliability of PDAF data.

An embodiment of the present invention provides a camera that acquires PDAF data from an image sensor and, when the reliability of the PDAF data is lower than a threshold value, rotates the image sensor by a predetermined angle to improve the reliability of PDAF data, and a control method thereof. It aims to do.

In another embodiment of the present invention, after rotating the image sensor by a predetermined angle, the reliability of the PDAF data is checked again, and if the reliability of the PDAF data is more than a threshold, the image sensor is rotated back to its original position, and the preview screen is displayed. An object of the present invention is to provide a camera capable of preventing an image from being rotated and a control method thereof.

Another embodiment of the present invention is to provide a camera and a method for controlling the same by rotating an image sensor by a predetermined angle so as to be less affected by the horizontal component when an image contains a large number of horizontal components.

The technical problem to be achieved in the present invention is not limited to the above-mentioned technical problem, and other technical problems not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. .

According to an aspect of the present invention, a camera includes a lens 210 that collects or radiates light coming from a subject to form an optical image; An image sensor 220 processing a first image corresponding to the subject; An auto focus actuator 230 for adjusting the focus applied to the image sensor by moving the lens 210 up and down; And phase detection auto focus data (PDAF data) while performing an Auto Focus Algorithm operation, from the image sensor 220, and the reliability of the acquired PDAF data is a preset threshold. If the value is higher than the value, the autofocus actuator 230 controls the lens 210 to move by a first predetermined distance, and when the reliability of the PDAF data is less than a preset threshold, the image sensor 220 is first It includes a control unit 240 that rotates by a predetermined angle in the direction.

According to another aspect of the present invention, a camera control method includes the steps of processing a first image corresponding to a subject (S310); Acquiring phase detection auto focus data (hereinafter, PDAF data) from the image sensor 220 while performing an auto focus algorithm operation (S320); If the reliability of the obtained PDAF data is greater than or equal to a preset threshold (S330), controlling the autofocus actuator 230 to move the lens 210 by a first predetermined distance (S340) and the PDAF data If the reliability is less than a preset threshold, rotating the image sensor 220 by a predetermined angle in the first direction (S350).

According to an embodiment of the present invention, when PDAF data is acquired from an image sensor and the reliability of the PDAF data is lower than a threshold value, the reliability of the PDAF data can be improved by rotating the image sensor by a predetermined angle. User convenience can be improved because the focus can be accurately adjusted.

According to another embodiment of the present invention, after rotating the image sensor by a predetermined angle, the reliability of the PDAF data is checked again, and if the reliability of the PDAF data is more than the threshold, the image sensor is rotated back to its original position, and the preview screen Since it is possible to prevent rotation of the image of, user convenience can be improved since the user can create an effect of viewing the preview screen of the same composition.

According to another embodiment of the present invention, when an image contains a large number of horizontal components, the reliability of PDAF data can be improved by rotating the image sensor by a predetermined angle to be less affected by the horizontal components. Because the focus can be accurately focused, user convenience can be improved.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the art from the following description. will be.

1A is a block diagram illustrating a mobile terminal related to the present invention.

1B and 1C are conceptual diagrams of an example of a mobile terminal according to the present invention viewed from different directions.

2 is a configuration diagram of a camera according to an embodiment of the present invention.

3 is a diagram illustrating a flow chart of a camera control method according to an embodiment of the present invention.

4 is a diagram illustrating a flow chart of a camera control method according to an embodiment of the present invention.

5 is a diagram illustrating a configuration of a camera mounted on a mobile device according to an embodiment of the present invention.

6 is a diagram showing the structure of a PDAF cell according to an embodiment of the present invention.

7 is a diagram illustrating an image in which PDAF data is well acquired and an image in which PDAF data is not well acquired according to an embodiment of the present invention.

8 is a diagram illustrating an image according to a distance between a subject and a focal point according to an embodiment of the present invention.

9 is a diagram illustrating a lens position and focus accuracy in an image in which PDAF data is well acquired according to an embodiment of the present invention.

10 is a diagram illustrating a lens position and focus accuracy of an image in which PDAF data is difficult to acquire according to an embodiment of the present invention.

11 is a diagram illustrating rotating an image sensor with respect to a lens according to an embodiment of the present invention.

12 is a diagram illustrating rotation of an image sensor by a predetermined angle with respect to a lens when a subject is a specific subject according to an embodiment of the present invention.

13 is a diagram illustrating a weight map and a confidence level map in a PDAF ROI area having a size of 6 x 6 according to an embodiment of the present invention.

14 is a diagram illustrating contents related to a confidence level and a local confidence level according to an embodiment of the present invention.

15 is a diagram illustrating an example of detecting a vertical edge and detecting a horizontal edge according to an embodiment of the present invention.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not have meanings or roles that are distinguished from each other by themselves.

In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description thereof will be omitted.

In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

Terms including ordinal numbers, such as first and second, may be used to describe various elements, but the elements are not limited by the terms. These terms are used only for the purpose of distinguishing one component from another component.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Mobile terminals described in this specification include mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, and slate PCs. , Tablet PC (tablet PC), ultrabook (ultrabook), wearable device (wearable device, for example, smartwatch, glass-type terminal (smart glass), HMD (head mounted display)), etc. may be included. have.

However, it will be readily apparent to those skilled in the art that the configuration according to the embodiment described in the present specification may also be applied to fixed terminals such as digital TVs, desktop computers, and digital signage, except when applicable only to mobile terminals. will be.

1A to 1C, FIG. 1A is a block diagram illustrating a mobile terminal related to the present invention, and FIGS. 1B and 1C are conceptual diagrams of an example of a mobile terminal related to the present invention viewed from different directions.

The mobile terminal 100 includes a wireless communication unit 110, an input unit 120, a sensing unit 140, an output unit 150, an interface unit 160, a memory 170, a control unit 180, and a power supply unit 190. ), etc. The components shown in FIG. 1A are not essential for implementing the mobile terminal, and thus, the mobile terminal described in the present specification may have more or fewer components than those listed above.

More specifically, among the components, the wireless communication unit 110 may be configured between the mobile terminal 100 and the wireless communication system, between the mobile terminal 100 and another mobile terminal 100, or between the mobile terminal 100 and an external server. It may include one or more modules that enable wireless communication between. In addition, the wireless communication unit 110 may include one or more modules for connecting the mobile terminal 100 to one or more networks.

The wireless communication unit 110 may include at least one of a broadcast reception module 111, a mobile communication module 112, a wireless Internet module 113, a short-range communication module 114, and a location information module 115. .

The input unit 120 includes a camera 121 or an image input unit for inputting an image signal, a microphone 122 for inputting an audio signal, or an audio input unit, and a user input unit 123 for receiving information from a user, for example, , A touch key, a mechanical key, etc. The voice data or image data collected by the input unit 120 may be analyzed and processed as a user's control command.

The sensing unit 140 may include one or more sensors for sensing at least one of information in the mobile terminal, information on surrounding environments surrounding the mobile terminal, and user information. For example, the sensing unit 140 includes a proximity sensor 141, an illumination sensor 142, a touch sensor, an acceleration sensor, a magnetic sensor, and gravity. G-sensor, gyroscope sensor, motion sensor, RGB sensor, infrared sensor (IR sensor), fingerprint sensor (finger scan sensor), ultrasonic sensor (ultrasonic sensor) , Optical sensor (for example, camera (see 121)), microphone (microphone, see 122), battery gauge, environmental sensor (for example, barometer, hygrometer, thermometer, radiation detection sensor, It may include at least one of a heat sensor, a gas sensor, etc.), and a chemical sensor (eg, an electronic nose, a healthcare sensor, a biometric sensor, etc.). Meanwhile, the mobile terminal disclosed in the present specification may combine and utilize information sensed by at least two or more of these sensors.

The output unit 150 is for generating an output related to visual, auditory or tactile sense, and includes at least one of the display unit 151, the sound output unit 152, the hap tip module 153, and the light output unit 154 can do. The display unit 151 may implement a touch screen by forming a layer structure or integrally with the touch sensor. Such a touch screen can function as a user input unit 123 that provides an input interface between the mobile terminal 100 and a user, and can provide an output interface between the mobile terminal 100 and a user.

The interface unit 160 serves as a passage between various types of external devices connected to the mobile terminal 100. The interface unit 160 connects a wired/wireless headset port, an external charger port, a wired/wireless data port, a memory card port, and a device equipped with an identification module. It may include at least one of a port, an audio input/output (I/O) port, an input/output (video I/O) port, and an earphone port. The mobile terminal 100 may perform appropriate control related to the connected external device in response to the connection of the external device to the interface unit 160.

In addition, the memory 170 stores data supporting various functions of the mobile terminal 100. The memory 170 may store a plurality of application programs or applications driven by the mobile terminal 100, data for operation of the mobile terminal 100, and commands. At least some of these application programs may be downloaded from an external server through wireless communication. In addition, at least some of these application programs may exist on the mobile terminal 100 from the time of delivery for basic functions of the mobile terminal 100 (eg, incoming calls, outgoing functions, message reception, and outgoing functions). Meanwhile, the application program may be stored in the memory 170, installed on the mobile terminal 100, and driven by the controller 180 to perform an operation (or function) of the mobile terminal.

In addition to the operation related to the application program, the controller 180 generally controls the overall operation of the mobile terminal 100. The controller 180 may provide or process appropriate information or functions to a user by processing signals, data, information, etc. input or output through the above-described components or by driving an application program stored in the memory 170.

Also, in order to drive an application program stored in the memory 170, the controller 180 may control at least some of the components examined together with FIG. 1A. Furthermore, in order to drive the application program, the controller 180 may operate by combining at least two or more of the components included in the mobile terminal 100 with each other.

The power supply unit 190 receives external power and internal power under the control of the controller 180 and supplies power to each of the components included in the mobile terminal 100. The power supply unit 190 includes a battery, and the battery may be a built-in battery or a replaceable battery.

At least some of the components may operate in cooperation with each other to implement an operation, control, or control method of a mobile terminal according to various embodiments described below. In addition, the operation, control, or control method of the mobile terminal may be implemented on the mobile terminal by driving at least one application program stored in the memory 170.

Hereinafter, before examining various embodiments implemented through the mobile terminal 100 described above, the above-listed components will be described in more detail with reference to FIG. 1A.

First, referring to the wireless communication unit 110, the broadcast reception module 111 of the wireless communication unit 110 receives a broadcast signal and/or broadcast-related information from an external broadcast management server through a broadcast channel. The broadcast channel may include a satellite channel and a terrestrial channel. Two or more broadcast receiving modules may be provided to the mobile terminal 100 for simultaneous broadcast reception or broadcast channel switching of at least two broadcast channels.

The broadcast management server may mean a server that generates and transmits a broadcast signal and/or broadcast-related information, or a server that receives and transmits a previously-generated broadcast signal and/or broadcast-related information to a terminal. The broadcast signal may include not only a TV broadcast signal, a radio broadcast signal, and a data broadcast signal, but also a broadcast signal in a form in which a data broadcast signal is combined with a TV broadcast signal or a radio broadcast signal.

The broadcast signal may be encoded according to at least one of technical standards (or a broadcast method, for example, ISO, IEC, DVB, ATSC, etc.) for transmission and reception of digital broadcast signals, and the broadcast reception module 111 The digital broadcast signal can be received using a method suitable for the technical standards set by technical standards.

The broadcast related information may mean information related to a broadcast channel, a broadcast program, or a broadcast service provider. The broadcast-related information may also be provided through a mobile communication network. In this case, it may be received by the mobile communication module 112.

The broadcast-related information may exist in various forms, such as an Electronic Program Guide (EPG) of Digital Multimedia Broadcasting (DMB) or an Electronic Service Guide (ESG) of Digital Video Broadcast-Handheld (DVB-H). The broadcast signal and/or broadcast related information received through the broadcast reception module 111 may be stored in the memory 160.

The mobile communication module 112 includes technical standards or communication methods for mobile communication (eg, GSM (Global System for Mobile communication), CDMA (Code Division Multi Access), CDMA2000 (Code Division Multi Access 2000)), EV -DO (Enhanced Voice-Data Optimized or Enhanced Voice-Data Only), WCDMA (Wideband CDMA), HSDPA (High Speed Downlink Packet Access), HSUPA (High Speed Uplink Packet Access), LTE (Long Term Evolution), LTE-A (Long Term Evolution-Advanced), etc.), transmits and receives radio signals with at least one of a base station, an external terminal, and a server on a mobile communication network.

The wireless signal may include a voice call signal, a video call signal, or various types of data according to transmission/reception of text/multimedia messages.

The wireless Internet module 113 refers to a module for wireless Internet access, and may be built-in or external to the mobile terminal 100. The wireless Internet module 113 is configured to transmit and receive wireless signals in a communication network according to wireless Internet technologies.

Examples of wireless Internet technologies include WLAN (Wireless LAN), Wi-Fi (Wireless-Fidelity), Wi-Fi (Wireless Fidelity) Direct, DLNA (Digital Living Network Alliance), WiBro (Wireless Broadband), WiMAX (World Interoperability for Microwave Access), HSDPA (High Speed Downlink Packet Access), HSUPA (High Speed Uplink Packet Access), LTE (Long Term Evolution), LTE-A (Long Term Evolution-Advanced), etc., and the wireless Internet module ( 113) transmits and receives data according to at least one wireless Internet technology in a range including Internet technologies not listed above.

From the point of view that wireless Internet access by WiBro, HSDPA, HSUPA, GSM, CDMA, WCDMA, LTE, LTE-A, etc. is made through a mobile communication network, the wireless Internet module 113 performs wireless Internet access through the mobile communication network. ) May be understood as a kind of the mobile communication module 112.

The short-range communication module 114 is for short-range communication, and includes Bluetooth, Radio Frequency Identification (RFID), Infrared Data Association (IrDA), Ultra Wideband (UWB), ZigBee, and NFC (Near Field Communication), Wi-Fi (Wireless-Fidelity), Wi-Fi Direct, and Wireless Universal Serial Bus (USB) technologies may be used to support short-range communication. , Between the mobile terminal 100 and the wireless communication system, between the mobile terminal 100 and another mobile terminal 100, or between the mobile terminal 100 and another mobile terminal 100, or through a wireless area network (Wireless Area Networks) An external server) may support wireless communication between networks located in. The short-range wireless communication network may be a short-range wireless personal area network.

Here, the other mobile terminal 100 is a wearable device capable of exchanging (or interlocking with) data with the mobile terminal 100 according to the present invention, for example, a smartwatch, a smart glasses. (smart glass), HMD (head mounted display)). The short-range communication module 114 may detect (or recognize) a wearable device capable of communicating with the mobile terminal 100 around the mobile terminal 100. Furthermore, when the sensed wearable device is a device that is authenticated to communicate with the mobile terminal 100 according to the present invention, the controller 180 transmits at least part of the data processed by the mobile terminal 100 to the short-range communication module ( 114) can be transmitted to the wearable device. Accordingly, a user of the wearable device can use data processed by the mobile terminal 100 through the wearable device. For example, according to this, when a call is received by the mobile terminal 100, the user performs a phone call through the wearable device, or when a message is received by the mobile terminal 100, the user receives the received call through the wearable device. It is possible to check the message.

The location information module 115 is a module for obtaining a location (or current location) of a mobile terminal, and representative examples thereof include a GPS (Global Positioning System) module or a WiFi (Wireless Fidelity) module. For example, if the mobile terminal utilizes the GPS module, it can acquire the location of the mobile terminal by using a signal transmitted from a GPS satellite. As another example, if the mobile terminal utilizes the Wi-Fi module, the mobile terminal may acquire the location of the mobile terminal based on information of the Wi-Fi module and a wireless access point (AP) that transmits or receives a wireless signal. If necessary, the location information module 115 may perform any function among other modules of the wireless communication unit 110 in order to obtain data on the location of the mobile terminal as a substitute or additionally. The location information module 115 is a module used to obtain the location (or current location) of the mobile terminal, and is not limited to a module that directly calculates or obtains the location of the mobile terminal.

Next, the input unit 120 is for inputting image information (or signal), audio information (or signal), data, or information input from a user. For inputting image information, the mobile terminal 100 Alternatively, a plurality of cameras 121 may be provided. The camera 121 processes an image frame such as a still image or a video obtained by an image sensor in a video call mode or a photographing mode. The processed image frame may be displayed on the display unit 151 or stored in the memory 170. On the other hand, a plurality of cameras 121 provided in the mobile terminal 100 may be arranged to form a matrix structure, and through the camera 121 forming a matrix structure as described above, various angles or focal points are applied to the mobile terminal 100. A plurality of image information may be input. In addition, the plurality of cameras 121 may be arranged in a stereo structure to obtain a left image and a right image for implementing a stereoscopic image.

The microphone 122 processes an external sound signal into electrical voice data. The processed voice data may be variously utilized according to a function (or an application program being executed) being executed by the mobile terminal 100. Meanwhile, the microphone 122 may be implemented with various noise removal algorithms for removing noise generated in a process of receiving an external sound signal.

The user input unit 123 is for receiving information from the user, and when information is input through the user input unit 123, the controller 180 can control the operation of the mobile terminal 100 to correspond to the input information. . Such, the user input unit 123 is a mechanical (mechanical) input means (or a mechanical key, for example, a button located on the front, rear or side of the mobile terminal 100, a dome switch (dome switch), a jog wheel, Jog switch, etc.) and a touch-type input means. As an example, the touch-type input means comprises a virtual key, a soft key, or a visual key displayed on a touch screen through software processing, or a portion other than the touch screen On the other hand, the virtual key or the visual key may be made of a touch key disposed on the touch screen, while having various forms and may be displayed on the touch screen. ), icon, video, or a combination thereof.

Meanwhile, the sensing unit 140 senses at least one of information in the mobile terminal, information on a surrounding environment surrounding the mobile terminal, and user information, and generates a sensing signal corresponding thereto. The controller 180 may control the driving or operation of the mobile terminal 100 or perform data processing, functions, or operations related to an application program installed in the mobile terminal 100 based on such a sensing signal. Representative sensors among various sensors that may be included in the sensing unit 140 will be described in more detail.

First, the proximity sensor 141 refers to a sensor that detects the presence or absence of an object approaching a predetermined detection surface or an object existing in the vicinity using the force of an electromagnetic field or infrared rays without mechanical contact. In the proximity sensor 141, the proximity sensor 141 may be disposed in an inner area of the mobile terminal surrounded by the touch screen as described above or near the touch screen.

Examples of the proximity sensor 141 include a transmission type photoelectric sensor, a direct reflection type photoelectric sensor, a mirror reflection type photoelectric sensor, a high frequency oscillation type proximity sensor, a capacitive type proximity sensor, a magnetic type proximity sensor, an infrared proximity sensor, and the like. When the touch screen is a capacitive type, the proximity sensor 141 may be configured to detect the proximity of the object by a change in the electric field according to the proximity of the conductive object. In this case, the touch screen (or touch sensor) itself may be classified as a proximity sensor.

On the other hand, for convenience of explanation, the action of allowing an object to be recognized as being positioned on the touch screen by being approached without contacting an object on the touch screen is called "proximity touch", and the touch The act of actually touching an object on the screen is referred to as "contact touch". A position at which an object is touched in proximity on the touch screen means a position at which the object is vertically corresponding to the touch screen when the object is touched in proximity. The proximity sensor 141 may detect a proximity touch and a proximity touch pattern (eg, proximity touch distance, proximity touch direction, proximity touch speed, proximity touch time, proximity touch position, proximity touch movement state, etc.). have. Meanwhile, as above, the controller 180 processes data (or information) corresponding to the proximity touch operation and the proximity touch pattern sensed through the proximity sensor 141, and further, provides visual information corresponding to the processed data. It can be output on the touch screen. Furthermore, the controller 180 may control the mobile terminal 100 to process different operations or data (or information) according to whether a touch to the same point on the touch screen is a proximity touch or a touch touch. .

The touch sensor applies a touch (or touch input) to the touch screen (or display unit 151) using at least one of various touch methods such as a resistive film method, a capacitive method, an infrared method, an ultrasonic method, and a magnetic field method. To detect.

As an example, the touch sensor may be configured to convert a pressure applied to a specific portion of the touch screen or a change in capacitance generated at a specific portion of the touch screen into an electrical input signal. The touch sensor may be configured to detect a location, an area, a pressure upon touch, a capacitance upon touch, and the like at which a touch object applying a touch on the touch screen is touched on the touch sensor. Here, the touch object is an object that applies a touch to the touch sensor, and may be, for example, a finger, a touch pen, a stylus pen, or a pointer.

In this way, when there is a touch input to the touch sensor, the signal(s) corresponding thereto is transmitted to the touch controller. The touch controller processes the signal(s) and then transmits the corresponding data to the controller 180. As a result, the controller 180 can know whether an area of the display unit 151 is touched. Here, the touch controller may be a separate component from the controller 180 or may be the controller 180 itself.

Meanwhile, the controller 180 may perform different controls or perform the same control according to the type of the touch object by touching the touch screen (or a touch key provided in addition to the touch screen). Whether to perform different controls or to perform the same control according to the type of the touch object may be determined according to an operating state of the mobile terminal 100 or an application program being executed.

Meanwhile, the touch sensor and the proximity sensor described above are independently or in combination, and a short (or tap) touch, a long touch, a multi touch, and a drag touch on the touch screen. ), flick touch, pinch-in touch, pinch-out touch, swipe touch, hovering touch, etc. You can sense the touch.

The ultrasonic sensor may recognize location information of a sensing target using ultrasonic waves. Meanwhile, the controller 180 may calculate the location of the wave generator through information sensed from the optical sensor and the plurality of ultrasonic sensors. The location of the wave generator may be calculated by using a property that the light is much faster than the ultrasonic wave, that is, the time that the light reaches the optical sensor is much faster than the time that the ultrasonic wave reaches the ultrasonic sensor. More specifically, the location of the wave generator may be calculated using a time difference between a time when the ultrasonic wave arrives using light as a reference signal.

On the other hand, the camera 121, viewed as the configuration of the input unit 120, includes at least one of a camera sensor (eg, CCD, CMOS, etc.), a photo sensor (or image sensor), and a laser sensor.

The camera 121 and the laser sensor may be combined with each other to detect a touch of a sensing target for a 3D stereoscopic image. The photosensor may be stacked on the display device, and the photosensor is configured to scan a motion of a sensing object close to the touch screen. More specifically, the photo sensor scans the contents placed on the photo sensor by mounting a photo diode and a transistor (TR) in a row/column and using an electrical signal that changes according to the amount of light applied to the photo diode. That is, the photosensor calculates the coordinates of the sensing object according to the amount of light change, and through this, position information of the sensing object may be obtained.

The display unit 151 displays (outputs) information processed by the mobile terminal 100. For example, the display unit 151 may display execution screen information of an application program driven in the mobile terminal 100, or UI (User Interface) and GUI (Graphic User Interface) information according to such execution screen information. .

In addition, the display unit 151 may be configured as a three-dimensional display unit that displays a three-dimensional image.

A three-dimensional display method such as a stereoscopic method (glasses method), an auto stereoscopic method (no glasses method), and a projection method (holographic method) may be applied to the stereoscopic display unit.

In general, a 3D stereoscopic image is composed of a left image (an image for the left eye) and a right image (an image for the right eye). Depending on how the left and right images are combined into a 3D stereoscopic image, a top-down method in which left and right images are arranged up and down in one frame, and left and right images are left and right within one frame. L-to-R (left-to-right, side by side) method, a checker board method in which pieces of left and right images are arranged in a tile form, and left and right images are arranged in columns Alternatively, it is divided into an interlaced method in which the image is alternately arranged in row units, and a time sequential (frame by frame) method in which the left image and the right image are alternately displayed by time.

In addition, the 3D thumbnail image may generate a left image thumbnail and a right image thumbnail from the left image and the right image of the original image frame, respectively, and may be generated as one image as they are combined. In general, a thumbnail refers to a reduced image or a reduced still image. The left image thumbnail and the right image thumbnail generated in this way are displayed with a left and right distance difference on the screen as much as a depth corresponding to the parallax between the left image and the right image, thereby representing a three-dimensional sense of space.

The left image and the right image required for realization of the 3D stereoscopic image may be displayed on the stereoscopic display unit by the stereoscopic processing unit. The 3D processing unit receives a 3D image (an image at a reference point of view and an image at an extended point of view) and sets a left image and a right image therefrom, or receives a 2D image and converts it into a left image and a right image.

The sound output unit 152 may output audio data received from the wireless communication unit 110 or stored in the memory 170 in a call signal reception, a call mode or a recording mode, a voice recognition mode, a broadcast reception mode, and the like. The sound output unit 152 also outputs sound signals related to functions (eg, a call signal reception sound, a message reception sound, etc.) performed in the mobile terminal 100. The sound output unit 152 may include a receiver, a speaker, and a buzzer.

The haptic module 153 generates various tactile effects that a user can feel. A typical example of the tactile effect generated by the haptic module 153 may be vibration. The intensity and pattern of vibrations generated by the haptic module 153 may be controlled by a user's selection or setting of a controller. For example, the haptic module 153 may synthesize and output different vibrations or sequentially output them.

In addition to vibration, the haptic module 153 is used for stimulation such as an arrangement of pins that move vertically with respect to the contact skin surface, blowing force or suction force of air through the injection or inlet, grazing against the skin surface, contact of electrodes, and electrostatic force. It can generate various tactile effects, such as the effect by the effect and the effect by reproducing the feeling of cooling and warming using an endothermic or heat generating element.

The haptic module 153 may not only deliver a tactile effect through direct contact, but may also be implemented so that a user can feel the tactile effect through muscle sensations such as a finger or an arm. Two or more haptic modules 153 may be provided depending on the configuration aspect of the mobile terminal 100.

The light output unit 154 outputs a signal for notifying the occurrence of an event using light from a light source of the mobile terminal 100. Examples of events occurring in the mobile terminal 100 may include message reception, call signal reception, missed call, alarm, schedule notification, email reception, and information reception through an application.

The signal output from the light output unit 154 is implemented as the mobile terminal emits a single color or multiple colors of light to the front or rear. The signal output may be terminated when the mobile terminal detects the user's event confirmation.

The interface unit 160 serves as a passage for all external devices connected to the mobile terminal 100. The interface unit 160 receives data from an external device or receives power and transmits it to each component inside the mobile terminal 100, or transmits data inside the mobile terminal 100 to an external device. For example, a wired/wireless headset port, an external charger port, a wired/wireless data port, a memory card port, a port for connecting a device equipped with an identification module. (port), an audio input/output (I/O) port, a video input/output (I/O) port, an earphone port, and the like may be included in the interface unit 160.

Meanwhile, the identification module is a chip that stores various types of information for authenticating the right to use the mobile terminal 100, and includes a user identification module (UIM), a subscriber identity module (SIM), and universal user authentication. It may include a module (universal subscriber identity module; USIM). A device equipped with an identification module (hereinafter referred to as'identification device') may be manufactured in the form of a smart card. Accordingly, the identification device may be connected to the terminal 100 through the interface unit 160.

In addition, the interface unit 160 serves as a path through which power from the cradle is supplied to the mobile terminal 100 when the mobile terminal 100 is connected to an external cradle, or is input from the cradle by a user. It may be a path through which various command signals are transmitted to the mobile terminal 100. Various command signals or the power input from the cradle may be operated as signals for recognizing that the mobile terminal 100 is correctly mounted on the cradle.

The memory 170 may store a program for the operation of the controller 180 and may temporarily store input/output data (eg, a phone book, a message, a still image, a video, etc.). The memory 170 may store data on vibrations and sounds of various patterns output when a touch input on the touch screen is performed.

The memory 170 is a flash memory type, a hard disk type, a solid state disk type, an SDD type, a multimedia card micro type. ), card-type memory (e.g., SD or XD memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read (EEPROM) -only memory), programmable read-only memory (PROM), magnetic memory, magnetic disk, and optical disk. The mobile terminal 100 may be operated in connection with a web storage that performs a storage function of the memory 170 over the Internet.

Meanwhile, as described above, the controller 180 controls an operation related to an application program and, in general, an overall operation of the mobile terminal 100. For example, when the state of the mobile terminal satisfies a set condition, the controller 180 may execute or release a lock state limiting input of a user's control command for applications.

In addition, the controller 180 performs control and processing related to voice calls, data communication, video calls, etc., or performs pattern recognition processing capable of recognizing handwriting input or drawing input performed on the touch screen as characters and images, respectively. I can. Furthermore, in order to implement various embodiments described below on the mobile terminal 100 according to the present invention, the controller 180 may control any one or a combination of a plurality of components described above.

The power supply unit 190 receives external power and internal power under the control of the controller 180 to supply power necessary for the operation of each component. The power supply unit 190 includes a battery, and the battery may be a built-in battery configured to be rechargeable, and may be detachably coupled to a terminal body for charging or the like.

Further, the power supply unit 190 may include a connection port, and the connection port may be configured as an example of an interface 160 to which an external charger supplying power for charging a battery is electrically connected.

As another example, the power supply unit 190 may be configured to charge the battery in a wireless manner without using the connection port. In this case, the power supply unit 190 uses at least one of an inductive coupling method based on a magnetic induction phenomenon or a magnetic resonance coupling method based on an electromagnetic resonance phenomenon from an external wireless power transmitter. Power can be delivered.

Meanwhile, hereinafter, various embodiments may be implemented in a recording medium that can be read by a computer or a similar device using, for example, software, hardware, or a combination thereof.

1B and 1C, the disclosed mobile terminal 100 includes a bar-shaped terminal body. However, the present invention is not limited thereto, and may be applied to various structures such as a watch type, a clip type, a glass type, or a folder type in which two or more bodies are relatively movably coupled, a flip type, a slide type, a swing type, and a swivel type. . Although it will be related to a specific type of mobile terminal, the description of a specific type of mobile terminal can be applied generally to other types of mobile terminals.

Here, the terminal body may be understood as a concept referring to the mobile terminal 100 as at least one aggregate.

The mobile terminal 100 includes a case (eg, a frame, a housing, a cover, etc.) forming an exterior. As shown, the mobile terminal 100 may include a front case 101 and a rear case 102. Various electronic components are disposed in an inner space formed by the combination of the front case 101 and the rear case 102. At least one middle case may be additionally disposed between the front case 101 and the rear case 102.

A display unit 151 is disposed on the front of the terminal body to output information. As illustrated, the window 151a of the display unit 151 may be mounted on the front case 101 to form the front surface of the terminal body together with the front case 101.

In some cases, electronic components may be mounted on the rear case 102 as well. Electronic components that can be mounted on the rear case 102 include a removable battery, an identification module, and a memory card. In this case, a rear cover 103 for covering the mounted electronic component may be detachably coupled to the rear case 102. Accordingly, when the rear cover 103 is separated from the rear case 102, the electronic components mounted on the rear case 102 are exposed to the outside.

As shown, when the rear cover 103 is coupled to the rear case 102, a part of the side surface of the rear case 102 may be exposed. In some cases, when the rear case 102 is combined, the rear case 102 may be completely covered by the rear cover 103. Meanwhile, the rear cover 103 may be provided with an opening for exposing the camera 121b or the sound output unit 152b to the outside.

These cases 101, 102, 103 may be formed by injection of synthetic resin or may be formed of a metal such as stainless steel (STS), aluminum (Al), titanium (Ti), or the like.

Unlike the above example in which a plurality of cases provide an inner space for accommodating various electronic components, the mobile terminal 100 may be configured such that one case provides the inner space. In this case, a unibody mobile terminal 100 in which synthetic resin or metal is connected from the side to the rear may be implemented.

Meanwhile, the mobile terminal 100 may include a waterproof unit (not shown) that prevents water from permeating into the terminal body. For example, the waterproof unit is provided between the window 151a and the front case 101, between the front case 101 and the rear case 102, or between the rear case 102 and the rear cover 103, and the combination thereof It may include a waterproof member for sealing the inner space.

The mobile terminal 100 includes a display unit 151, first and second sound output units 152a and 152b, a proximity sensor 141, an illuminance sensor 142, a light output unit 154, and first and second sound output units. Cameras 121a and 121b, first and second operation units 123a and 123b, microphone 122, interface unit 160, and the like may be provided.

In the following, as shown in FIGS. 1B and 1C, a display unit 151, a first sound output unit 152a, a proximity sensor 141, an illuminance sensor 142, and a light output unit ( 154), a first camera 121a and a first operation unit 123a are disposed, a second operation unit 123b, a microphone 122, and an interface unit 160 are disposed on the side of the terminal body, and the terminal body The mobile terminal 100 in which the second sound output unit 152b and the second camera 121b are disposed on the rear surface of will be described as an example.

However, these configurations are not limited to this arrangement. These configurations may be excluded or replaced as necessary, or may be disposed on different sides. For example, the first operation unit 123a may not be provided on the front surface of the terminal body, and the second sound output unit 152b may be provided on the side of the terminal body rather than on the rear surface of the terminal body.

The display unit 151 displays (outputs) information processed by the mobile terminal 100. For example, the display unit 151 may display execution screen information of an application program driven in the mobile terminal 100, or UI (User Interface) and GUI (Graphic User Interface) information according to such execution screen information. .

The display unit 151 includes a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT LCD), an organic light-emitting diode (OLED), and a flexible display. display), a 3D display, and an e-ink display.

In addition, two or more display units 151 may exist depending on the implementation type of the mobile terminal 100. In this case, the mobile terminal 100 may have a plurality of display units spaced apart or integrally disposed on one surface, or may be disposed on different surfaces.

The display unit 151 may include a touch sensor that senses a touch on the display unit 151 so as to receive a control command by a touch method. Using this, when a touch is made to the display unit 151, the touch sensor detects the touch, and the controller 180 may be configured to generate a control command corresponding to the touch based on this. Content input by the touch method may be letters or numbers, or menu items that can be indicated or designated in various modes.

On the other hand, the touch sensor is configured in the form of a film having a touch pattern and is disposed between the window 151a and a display (not shown) on the rear surface of the window 151a, or a metal wire patterned directly on the rear surface of the window 151a. May be. Alternatively, the touch sensor may be integrally formed with the display. For example, the touch sensor may be disposed on a substrate of the display or may be provided inside the display.

As such, the display unit 151 may form a touch screen together with a touch sensor, and in this case, the touch screen may function as a user input unit 123 (see FIG. 1A). In some cases, the touch screen may replace at least some functions of the first manipulation unit 123a.

The first sound output unit 152a may be implemented as a receiver that transmits a call sound to the user's ear, and the second sound output unit 152b is a loud speaker that outputs various alarm sounds or multimedia playback sounds. ) Can be implemented.

A sound hole for emitting sound generated from the first sound output unit 152a may be formed in the window 151a of the display unit 151. However, the present invention is not limited thereto, and the sound may be configured to be emitted along an assembly gap between structures (eg, a gap between the window 151a and the front case 101). In this case, the externally formed hole for sound output is not visible or hidden, so that the appearance of the mobile terminal 100 may be more simple.

The light output unit 154 is configured to output light for notifying when an event occurs. Examples of the event include message reception, call signal reception, missed call, alarm, schedule notification, email reception, and information reception through an application. When the user's event confirmation is detected, the controller 180 may control the light output unit 154 to terminate the light output.

The first camera 121a processes an image frame of a still image or moving image obtained by an image sensor in a photographing mode or a video call mode. The processed image frame may be displayed on the display unit 151 and may be stored in the memory 170.

The first and second manipulation units 123a and 123b are an example of a user input unit 123 that is manipulated to receive a command for controlling the operation of the mobile terminal 100, and may also be collectively referred to as a manipulating portion. have. The first and second operation units 123a and 123b may be employed in any manner as long as the user operates while receiving a tactile feeling such as touch, push, and scroll. In addition, the first and second manipulation units 123a and 123b may also be employed in a manner in which the first and second manipulation units 123a and 123b are operated without a user's tactile feeling through proximity touch, hovering touch, or the like.

In this drawing, the first manipulation unit 123a is illustrated as being a touch key, but the present invention is not limited thereto. For example, the first operation unit 123a may be a push key (mechanical key) or may be configured as a combination of a touch key and a push key.

Contents input by the first and second manipulation units 123a and 123b may be variously set. For example, the first operation unit 123a receives commands such as menu, home key, cancel, search, etc., and the second operation unit 123b is output from the first or second sound output units 152a, 152b. Commands such as adjusting the volume of sound and switching to the touch recognition mode of the display unit 151 may be input.

Meanwhile, as another example of the user input unit 123, a rear input unit (not shown) may be provided on the rear surface of the terminal body. This rear input unit is manipulated to receive a command for controlling the operation of the mobile terminal 100, and input contents may be variously set. For example, commands such as power on/off, start, end, scroll, etc., control the volume of sound output from the first and second sound output units 152a and 152b, and touch recognition mode of the display unit 151 You can receive commands such as conversion of. The rear input unit may be implemented in a form capable of inputting by a touch input, a push input, or a combination thereof.

The rear input unit may be disposed to overlap the front display unit 151 in the thickness direction of the terminal body. As an example, when the user holds the terminal body with one hand, the rear input unit may be disposed on the rear upper end of the terminal body so that the user can easily manipulate the terminal body using the index finger. However, the present invention is not necessarily limited thereto, and the position of the rear input unit may be changed.

When the rear input unit is provided on the rear surface of the terminal body, a new type of user interface can be implemented using the rear input unit. In addition, when the touch screen or the rear input unit described above replaces at least some functions of the first operation unit 123a provided on the front of the terminal body, and the first operation unit 123a is not disposed on the front of the terminal body, The display unit 151 may be configured with a larger screen.

Meanwhile, the mobile terminal 100 may be provided with a fingerprint recognition sensor for recognizing a user's fingerprint, and the controller 180 may use fingerprint information detected through the fingerprint recognition sensor as an authentication means. The fingerprint recognition sensor may be embedded in the display unit 151 or the user input unit 123.

The microphone 122 is configured to receive a user's voice and other sounds. The microphone 122 may be provided in a plurality of locations and configured to receive stereo sound.

The interface unit 160 becomes a passage through which the mobile terminal 100 can be connected to an external device. For example, the interface unit 160 is a connection terminal for connection with other devices (eg, earphones, external speakers), a port for short-range communication (eg, an infrared port (IrDA Port), a Bluetooth port (Bluetooth Port), a wireless LAN port, etc.], or at least one of a power supply terminal for supplying power to the mobile terminal 100. The interface unit 160 may be implemented in the form of a socket for accommodating an external card such as a subscriber identification module (SIM) or a user identity module (UIM), or a memory card for storing information.

A second camera 121b may be disposed on the rear surface of the terminal body. In this case, the second camera 121b has a photographing direction substantially opposite to that of the first camera 121a.

The second camera 121b may include a plurality of lenses arranged along at least one line. The plurality of lenses may be arranged in a matrix format. Such a camera may be referred to as an'array camera'. When the second camera 121b is configured as an array camera, an image may be photographed in various ways using a plurality of lenses, and an image of better quality may be obtained.

The flash 124 may be disposed adjacent to the second camera 121b. The flash 124 illuminates light toward the subject when the subject is photographed by the second camera 121b.

A second sound output unit 152b may be additionally disposed on the terminal body. The second sound output unit 152b may implement a stereo function together with the first sound output unit 152a, and may be used to implement a speakerphone mode during a call.

At least one antenna for wireless communication may be provided in the terminal body. The antenna may be embedded in the terminal body or may be formed in a case. For example, an antenna forming a part of the broadcast receiving module 111 (refer to FIG. 1A) may be configured to be retractable from the terminal body. Alternatively, the antenna may be formed in a film type and attached to the inner surface of the rear cover 103, or a case including a conductive material may be configured to function as an antenna.

The battery 191 may be configured to receive power through a power cable connected to the interface unit 160. In addition, the battery 191 may be configured to enable wireless charging through a wireless charger. The wireless charging may be implemented by a magnetic induction method or a resonance method (magnetic resonance method).

On the other hand, in this drawing, the rear cover 103 is coupled to the rear case 102 so as to cover the battery 191 to limit the separation of the battery 191, and to protect the battery 191 from external shock and foreign substances. It is illustrated. When the battery 191 is configured to be detachably attached to the terminal body, the rear cover 103 may be detachably coupled to the rear case 102.

An accessory that protects the exterior of the mobile terminal 100 or assists or expands the function of the mobile terminal 100 may be added. An example of such an accessory may be a cover or a pouch that covers or accommodates at least one surface of the mobile terminal 100. The cover or pouch may be configured to interlock with the display unit 151 to expand functions of the mobile terminal 100. Another example of an accessory may be a touch pen for assisting or extending a touch input to a touch screen.

Meanwhile, in the present invention, information processed by a mobile terminal can be displayed using a flexible display. Hereinafter, based on the accompanying drawings, this will be described in more detail.

Further, hereinafter, embodiments of the present invention will be described by taking the camera shown in FIG. 2 as a camera as an example. However, it goes without saying that the camera according to an embodiment of the present invention may be mounted and implemented in the mobile device shown in FIGS. 1A to 1C.

In addition, hereinafter, referring to FIGS. 2 to 14, the camera and a control method thereof will be described in detail. However, the person skilled in the art may supplementary interpretations of FIGS. 2 to 14 or modify the embodiments with reference to FIGS. 1A to 1C described previously.

2 is a configuration diagram of a camera according to an embodiment of the present invention.

The camera 200 includes a lens 210, an image sensor 220, an auto focus actuator 230, a control unit 240, and a filter 250.

The lens 210 collects or radiates light coming from the subject to form an optical image.

The lens 210 for a mobile phone camera is a component constituting a camera module, and is generally supplied in the form of a module in which several lenses having respective characteristics are assembled to a barrel rather than a single lens. The camera phone lens 210 is divided into a spherical lens having a constant radius of curvature and an aspherical lens whose radius of curvature increases toward the periphery.

Multiple spherical lenses can be used to overcome spherical aberration (focal error) where the position of the focal point formed at the center and the periphery of the lens is different. As the dispersion is small and there is no blurring of the peripheral field, aspherical lenses are used more.

The image sensor 220 processes a first image corresponding to a subject. The image sensor 220 converts image information of a subject into an electrical image signal.

The auto focus actuator 230 adjusts the focus formed on the image sensor 220 by moving the lens 210 up and down.

The controller 240 acquires phase detection auto focus data (hereinafter, PDAF data) from the image sensor 220 while performing an auto focus algorithm operation, and the reliability of the acquired PDAF data When is greater than or equal to a preset threshold, the autofocus actuator 230 controls the lens 210 to move by a first predetermined distance, and if the reliability of the PDAF data is less than a preset threshold, the image sensor 220 It rotates by a predetermined angle in the first direction.

Here, the predetermined angle means the angle at which the horizontal component of the image displayed on the current screen is minimized. That is, when the horizontal component of the image is minimized, the reliability of PDAF data can be improved. The first direction may be clockwise or counterclockwise.

If the reliability of the PDAF data is less than a preset threshold, the control unit 240 checks whether the image sensor can be rotated, and if the image sensor can be rotated, the controller 240 executes an image sensor rotation autofocus algorithm, and operates the image sensor. If it cannot rotate, the contrast auto focus algorithm is executed.

The controller 240 determines the reliability of the PDAF data based on the defocust accuracy of the PDAF data and the contrast detection value through the horizontal edge filter.

For example, if the defocust accuracy of the PDAF data is less than the confidence level and the contrast detection value through the horizontal edge filter is less than the threshold value, the controller 240 determines that the reliability of the PDAF data is less than the preset threshold.

In the present invention, the reliability of PDAF data is not limited to the above-described method, and may be determined in various ways.

The reliability of PDAF data can be 0 to 100%.

3 is a diagram illustrating a flow chart of a camera control method according to an embodiment of the present invention. The present invention is carried out by the control unit 240.

Referring to FIG. 3, a first image corresponding to a subject is processed (S310).

Phase detection auto focus data (hereinafter, PDAF data) is acquired from the image sensor 220 while the auto focus algorithm is being operated (S320).

When the reliability of the acquired PDAF data is greater than or equal to a preset threshold (S330), the autofocus actuator 230 controls the lens 210 to move by a first predetermined distance (S340).

That is, if the reliability of the PDAF data is greater than or equal to a preset threshold, the position of the lens 210 to be moved based on the PDAF data is identified within 1 frame, and the control unit 240 detects the autofocus actuator 230 and the lens 210 Is controlled to move by a first predetermined distance within 30 to 40 msec.

If the reliability of the PDAF data is less than a preset threshold, the image sensor 220 is rotated in the first direction by a predetermined angle (S350). The first direction may be clockwise or counterclockwise. Here, the predetermined angle means the angle at which the horizontal component of the image displayed on the current screen is minimized. That is, when the horizontal component of the image is minimized, the reliability of PDAF data can be improved.

According to an embodiment of the present invention, when the reliability of PDAF data is low, the image sensor is rotated. In this case, the image sensor rotation is used within 1 frame as to whether to use the image sensor rotation AF algorithm, and the PDAF Data is received, the lens 210 is moved based on the data, and the image sensor 220 is restored to its original state, which is more than two frames slower than when the reliability of PDAF data is high.

4 is a diagram illustrating a flow chart of a camera control method according to an embodiment of the present invention. 4 is performed by the control unit 240.

First, the AF operation is performed (S410). Here, the AF operation means execution of the camera's auto focus algorithm.

PDAF data is acquired from the image sensor 220 (S420).

When the reliability of the acquired PDAF data is greater than or equal to a preset threshold (S430), the autofocus actuator 230 controls the lens 210 to move to the target position (S440). Here, the target position may be a distance away from the current lens position by a first predetermined distance.

If the reliability of the PDAF data is less than the preset threshold (S430), it is checked whether the image sensor can be rotated, and the step of executing the image sensor rotation AF algorithm is entered (S510).

The image sensor rotation AF algorithm will be described.

When the image sensor can be rotated (S510), the image sensor rotation auto focus algorithm is executed, and the image sensor is rotated by a predetermined angle (S520). Here, the predetermined angle means the angle at which the horizontal component of the image displayed on the current screen is minimized. That is, when the horizontal component of the image is minimized, the reliability of PDAF data can be improved.

If the image sensor cannot be rotated, a contrast autofocus algorithm is executed, and contrast data of the current lens position is checked (S610) .

After rotating the image sensor 220, PDAF data is obtained from the image sensor 220 (S530).

When the reliability of the acquired PDAF data is greater than or equal to a preset threshold (S540), the autofocus actuator 230 controls the lens 210 to move to the target position (S550). Here, the target position may be a distance away from the current lens position by a first predetermined distance.

If the reliability of the PDAF data is less than the preset threshold (S540), the contrast data of the current lens position is checked, and the step of executing the contrast AF algorithm is entered (S610).

The contrast AF algorithm will be described.

The contrast AF algorithm is a method of focusing by discriminating between the contrast of the subject, that is, the difference between the bright and dark areas. If the focus is correct, the outline of the image becomes clear and the contrast (contrast) increases, and if the focus is not correct, the outline becomes blurred and the contrast decreases. When using the camera, if you focus with the shutter button halfway, the image displayed on the LCD screen becomes blurred and clear repeatedly, and you can see that the focus is achieved. That is, the camera 200 moves the lens 210 to find a place with the highest contrast.

If the image sensor cannot be rotated, contrast data is checked at the current position of the lens (S610). Specifically, the control unit 240 checks the contrast ratio of the contrast data.

The moving direction of the lens 210 is determined (S620). When the image sensor 220 is in the xy plane, the lens 210 may move up and down the z-axis with respect to the xy plane.

The auto focus actuator 230 is controlled to move the lens 210 by the first distance in the second direction corresponding to the determined moving direction (S630). For example, the auto focus actuator 230 may control the lens 210 to move upward by a first distance.

The controller 240 checks the previous focus value and the current focus value (S640). Here, the focal value means the degree to which focus is well achieved. For example, the focus value has a value of 0 to 1, 0 means out of focus, and 1 means accurate focus.

If the previous focus value is greater than or equal to the current focus value (S640), the auto focus actuator 230 controls the lens to move by a first distance in a direction opposite to the second direction (S650). For example, the auto focus actuator 230 may control the lens 210 to move downward by a first distance. That is, the auto focus actuator moves the lens 210 to the previous position.

If the previous focus value is less than the current focus value (S640), the contrast data of the current lens position is reconfirmed (S610).

There is a question whether it is possible to extract PDAF data from the first frame. According to the present invention, the controller 240 may extract the PDAF data from the first frame and edge information used for the contrast AF algorithm.

5 is a diagram illustrating a configuration of a camera mounted on a mobile device according to an embodiment of the present invention.

Referring to FIG. 5, the camera 200 may be mounted on the mobile device 100.

The camera 200 includes a lens 210, an image sensor 220, an auto focus actuator 230, a control unit 240, a filter 250, and an RF-PCB substrate 260.

The lens 210 collects or radiates light coming from the subject to form an optical image.

The image sensor 220 processes a first image corresponding to a subject.

The auto focus actuator 230 adjusts the focus formed on the image sensor 220 by moving the lens 210 up and down.

The controller 240 acquires phase detection auto focus data (hereinafter, PDAF data) from the image sensor 220 while performing an auto focus algorithm operation, and the reliability of the acquired PDAF data is If it is more than a preset threshold, the autofocus actuator 230 controls the lens 210 to move by a first predetermined distance, and if the reliability of the PDAF data is less than the preset threshold, the image sensor 220 is moved in the first direction. Rotates by a predetermined angle.

The filter 250 includes an IR filter and a blue filter.

The RF-PCB substrate 260 refers to a substrate composed of a rigid portion and a flex portion. The RF-PCV substrate 260 may be connected to a three-dimensional circuit by bending the flex portion. The RF-PCB board 260 is advantageous in miniaturization because it does not require a connector for connection between modules, and it is possible to improve design freedom by maximizing set space utilization.

6 is a diagram illustrating a structure of a PDAF cell according to an embodiment of the present invention. 6 includes FIGS. 6(a) and 6(b). 6(a) is a diagram showing the structure of a PDAF cell.

Referring to FIG. 6(a), a view of an upper portion is a view showing an on chip lens (OCL) 60. The lower part is a view showing a color filter (CF) 62.

6(b) is a diagram showing a top view and a side view of a PDAF cell. Referring to FIG. 6(b), the diagram on the left side is a view showing a top view of the PDAF cell, and the diagram on the right side is a side view of the PDAF cell.

As the application of phase detection, which can measure the distance within an image sensor, is becoming common, the auto focus algorithm is operating based on PDAF distance extraction. Although the distance measurement of the PDAF cell must be accurate, if there are many horizontal components in the image due to the structural characteristics of the PDAF cell, the reliability of the PDAF data is degraded.

7 is a diagram illustrating an image in which PDAF data is well acquired and an image in which PDAF data is not well acquired according to an embodiment of the present invention. 7 includes FIGS. 7(a) and 7(b).

7(a) shows an image with many vertical components. 7B shows an image with many horizontal components.

Referring to FIG. 7(a), since the image contains many vertical components, it is easy to obtain PDAF data.

Referring to FIG. 7(b), it is difficult to obtain PDAF data because the image contains many horizontal components. An embodiment in which an image contains a large number of horizontal components may be a wall, a blackboard, a desk, or a laptop screen.

According to the present invention, when an image contains a large number of horizontal components, the image sensor is rotated in the first direction by a predetermined angle to remove the horizontal component, thereby improving the reliability of PDAF data.

8 is a diagram illustrating an image according to a distance between a subject and a focal point according to an embodiment of the present invention. 8 includes FIGS. 8(a), 8(b), and 8(c).

8(a) is a diagram showing a case where the focus is closer than that of the subject.

8(b) is a diagram illustrating a case in which focus is achieved.

8(a) is a diagram showing a case where the focus is farther than the subject.

9 is a diagram illustrating a lens position and focus accuracy in an image in which PDAF data is well acquired according to an embodiment of the present invention.

Referring to FIG. 9, the horizontal axis indicates a lens position. That is, it means the distance from the camera to the subject. The horizontal axis can be normalized and displayed as 0 to 100. When the lens position is 0, it means that the focus is closer than the subject.

If the lens position is 50, it means that it is in focus.

If the lens position is 100, it means that the focus is farther than the subject.

The vertical axis refers to the distance from the current lens position to the focus position. Therefore, the coordinates are (x, y) = (lens position, the distance from the current lens position to the focus position. The vertical axis indicates reliability. The reliability has a value between 0 and 100%.

For example, in the case of (0, 50), the lens must be moved by + 50 to achieve focus.

In the case of (50, 0), the lens is in focus at the current position, and there is no need to move the lens.

In the case of (100, 0), focus is achieved only when the lens is moved by -50.

Here, defocust refers to a distance from a current position to a focused lens position, and a confidence level refers to the accuracy of a defocust value obtained at a corresponding lens position.

Referring to FIG. 9, when an image contains a large number of vertical components, defocusing forms a first-order straight line according to a lens position, and reliability is formed close to 100%. When the image contains a lot of vertical components, it is easy to obtain PDAF data.

10 is a diagram illustrating a lens position and focus accuracy of an image in which PDAF data is difficult to acquire according to an embodiment of the present invention.

Referring to FIG. 10, the horizontal axis indicates the lens position. That is, it means the distance from the camera to the subject. The horizontal axis can be normalized and displayed as 0 to 100. When the lens position is 0, it means that the focus is closer than the subject.

If the lens position is 50, it means that it is in focus.

If the lens position is 100, it means that the focus is farther than the subject.

The vertical axis refers to the distance from the current lens position to the focus position. Therefore, the coordinates (x, y) = (lens position, the distance from the current lens position to the focus position. In addition, the vertical axis represents the reliability. The reliability has a value between 0 and 100%.

Referring to FIG. 10, defocust does not form a first-order straight line, and reliability is unknown. Therefore, it is not possible to find the lens position in focus.

11 is a diagram illustrating rotating an image sensor with respect to a lens according to an embodiment of the present invention. 11 includes FIGS. 11(a), 11(b) and 11(c).

11(a) is a diagram illustrating a rotation direction of an image sensor. Referring to FIG. 11(a), the image sensor 220 may move up and down on the +z axis, and may rotate counterclockwise "nyun*" or clockwise based on the +Z axis.

Fig. 11(b) is a diagram illustrating the prior art. Referring to FIG. 11B, the lens 210 may be moved up and down along the + z axis. In this case, the control unit 240 adjusts the distance to the image sensor 220 along the z-axis and focuses. In the case of the prior art, the lens 210 can only be moved up and down, and the image sensor 220 cannot be rotated.

11(c) is a diagram illustrating the present invention. Referring to FIG. 11C, the controller 240 may move the lens 210 vertically along the + z axis. In addition, the controller 240 may rotate the image sensor 220 counterclockwise or clockwise based on the z-axis. When the image sensor 22 is rotated counterclockwise or clockwise based on the z-axis, reliability of PDAF data can be improved.

In the case of the prior art, when the reliability of the PDAF data is low, the lens 210 is moved for every frame by executing a contrast auto focus algorithm, and the accuracy of focusing by analyzing the contrast of the screen is low and it takes a lot of time.

According to the present invention, when the reliability of the PDAF data is low, the image sensor 220 can be rotated to obtain PDAF data with high reliability, so that the focus can be more accurately focused and the focusing time can be reduced.

For example, according to an embodiment of the present invention, when the image sensor 220 is rotated, focus may be achieved within 3 frames.

12 is a diagram illustrating rotation of an image sensor by a predetermined angle with respect to a lens when an image of a subject contains a large number of horizontal components according to an embodiment of the present invention. 12 includes FIGS. 12(a) and 12(b).

FIG. 12(a) is a diagram showing that the image 1210 of a subject contains a large amount of horizontal components. Referring to FIG. 12A, since the image 1210 of the subject contains a large amount of horizontal components, the reliability of PDAF data is low.

12(b) is a view showing a top view of rotating the image sensor with respect to the lens by a predetermined angle.

Referring to the first embodiment (1), it is a diagram illustrating that the image sensor 220 is rotated by 0 degrees with respect to the lens 210.

In the case of the second embodiment (2), a diagram showing that the image sensor 220 is rotated counterclockwise with respect to the lens 210 by a first angle. For example, the first angle may be 1 degree.

In the case of the third embodiment (3), a diagram showing that the image sensor 220 is rotated counterclockwise with respect to the lens 210 by a second angle. The second angle is an angle greater than the first angle. When the rotation angle is the second angle, the horizontal component of the image is smaller than that of the first angle. For example, the first angle may be 1 degree and the second angle may be 2 degrees.

In the case of the fourth embodiment (4), a diagram showing that the image sensor 220 is rotated clockwise with respect to the lens 210 by a first angle. For example, the first angle may be 1 degree.

In the case of the fifth embodiment (5), a diagram showing that the image sensor 220 is rotated clockwise with respect to the lens 210 by a second angle. The second angle is an angle greater than the first angle. When the rotation angle is the second angle, the horizontal component of the image is smaller than that of the first angle. For example, the first angle may be 1 degree and the second angle may be 2 degrees.

The controller 240 rotates the image sensor 220 by a predetermined angle in a rotational direction around an axis in a horizontal plane parallel to the moving direction of the lens 210. Specifically, the controller 240 rotates the image sensor 220 with a motor (not shown) in a rotational direction around an axis in a horizontal plane parallel to the moving direction of the lens 210.

Here, the predetermined angle means an angle at which the horizontal component of the image displayed on the screen is minimized.

The controller 240 rotates the image sensor 220 ROLL based on the z-axis, and improves the reliability of PDAF data. The reliability of PDAF data decreases as the number of horizontal components of the image 1210 of the subject increases.

Accordingly, in the third embodiment (3), the horizontal component of the subject image 1210 is smaller than in the second embodiment (2). Therefore, the reliability of PDAF data is higher, and focus can be more accurately achieved. .

In addition, the fifth embodiment (5) has fewer horizontal components of the subject image 1210 than the fourth embodiment (4). Therefore, the reliability of PDAF data is higher, and focus can be more accurately achieved. .

Next, a technique for returning the preview screen to its original state when rotating the image sensor will be described.

When the image sensor 220 is rotated by a predetermined angle in the clockwise direction, the image displayed on the preview screen is also rotated by a predetermined angle in the clockwise direction. In this case, the user feels uncomfortable as he sees the rotated image on the preview screen.

First, the frame skipping will be described.

The control unit 240 skips a frame corresponding to a time while the image sensor 220 is rotating. For example, when the image sensor 220 rotates for 40 ms and returns to its original position, the frame corresponding to the 40 ms time is skipped.

Second, the image is rotated in a direction opposite to that of the image sensor.

The controller 240 rotates the first image by a predetermined angle in a direction opposite to the first direction, and displays the rotated first image on the preview screen.

That is, when the image sensor 220 is rotated by a predetermined angle in the clockwise direction, the control unit 240 rotates the first image by a predetermined angle in the counterclockwise direction, and displays the rotated first image on the preview screen.

According to the present invention, even if the image displayed on the preview screen is distorted by rotating the image sensor 220, the preview screen is restored to its original state, thereby providing the user with a feeling of continuously viewing the same composition.

13 is a diagram illustrating a weight map and a confidence level map in a PDAF ROI area having a size of 6 x 6 according to an embodiment of the present invention.

Referring to FIG. 13, FIG. 13(a) is a diagram illustrating a weight map of a 6 x 6 PDAF ROI area. 13(b) is a diagram showing a reliability level map of a 6 x 6 PDAF ROI area.

First, a method of estimating the reliability of PDAF data will be described.

First, it is a method of using the reliability level of the entire domain.

The controller 240 determines the reliability by comparing the overall average reliability value and the local average value of the PDAF region with a specific threshold value. The controller 240 divides the PDAF area into an M×N shape having a specific number of pixels. Each region has the same number of pixels.

The control unit 240 sets each to have a weight map corresponding to the ROI area. In this case, it is set variably in consideration of the illuminance condition.

In addition, the global confidence level means the average of the reliability of the entire PDAF area in consideration of the weight. M and N are variable depending on the camera sensor and can have various sizes such as 6 x 6, 8 x 6, 16 x 8, 4 x 4, 32 x 32, 32 x 24.

Second, it is a method of using the reliability level of the local domain.

The control unit 240 creates a larger ROI by locally adding the ROI divided by the local reliability level by M x N, and calculates the reliability corresponding to each ROI.

In this case, the controller 240 sets a threshold corresponding to each ROI in consideration of not only the illuminance condition but also lens shading. In this case, the peripheral portion of the lens 210 determines that PDAF information cannot be accurately performed as a noise signal due to shading, and thus the weight is set small.

Referring to FIG. 13(a), the entire area 1310 refers to an area obtained by dividing one image into 6×6 areas, and the local area 1312 is a 2×2 area of a partial area of the total area 1310. It means the area divided by.

13(b), the entire area 1320 refers to an area obtained by dividing one image into 6×6 areas, and the local area 1322 indicates a partial area of the total area 1320 2×2 areas. It means the area divided by.

When acquiring PDAF data from the image sensor 220, if the entire area is used, as an advantage, more detailed data can be obtained than when using a local area when acquiring PDAF data, and as a disadvantage, it is vulnerable to noise.

When acquiring PDAFT data from the image sensor 220, if a local area is used, it is robust against noise as an advantage, and as a disadvantage, detailed data cannot be obtained than when using the entire area when acquiring PDAF data.

14 is a diagram illustrating contents related to a confidence level and a local confidence level according to an embodiment of the present invention. Fig. 14 includes Figs. 14(a) and 14(b).

14(a) shows an equation of the confidence level.

Referring to FIG. 14A, the confidence level refers to a value obtained by dividing the entire region into M x N regions, adding a value obtained by multiplying the weight and the confidence level for each individual region, and dividing this by M x N.

14(b) shows an equation of a local confidence level.

Referring to FIG.14(b), the local confidence level refers to a value obtained by dividing a local region corresponding to a partial region of the entire region into mxn regions, adding a value obtained by multiplying the weight and the confidence level for each individual region, and dividing this by mxn. do.

15 is a diagram illustrating an example of detecting a vertical edge and detecting a horizontal edge according to an embodiment of the present invention. Referring to FIG. 15, FIG. 15 includes FIGS. 15(a), 15(b) and 15(c).

15(a) is a diagram showing an original image 1510.

FIG. 15B is a diagram illustrating an image 1520 in which a vertical edge component of the original image 1510 is detected by applying a Sobel X filter.

FIG. 15C is a diagram illustrating an image 1530 in which a horizontal edge component of the original image 1510 is detected by applying a Sobel Y filter.

Sobel filter refers to a filter that detects edge components in the horizontal and vertical directions of an image. Applying the Sobel X filter detects the vertical edge component of the image. Applying the Sobel Y filter detects the horizontal edge component of the image.

According to an embodiment of the present invention, when PDAF data is acquired from an image sensor and the reliability of the PDAF data is lower than a threshold value, the reliability of the PDAF data can be improved by rotating the image sensor by a predetermined angle. User convenience can be improved because the focus can be accurately adjusted.

According to another embodiment of the present invention, after rotating the image sensor by a predetermined angle, the reliability of the PDAF data is checked again, and if the reliability of the PDAF data is more than the threshold, the image sensor is rotated back to its original position, and the preview screen Since it is possible to prevent rotation of the image of, user convenience can be improved since the user can create an effect of viewing the preview screen of the same composition.

According to another embodiment of the present invention, when an image contains a large number of horizontal components, the reliability of PDAF data can be improved by rotating the image sensor by a predetermined angle to be less affected by the horizontal components. Because the focus can be accurately focused, user convenience can be improved.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains, various modifications and variations can be made without departing from the essential characteristics of the present invention. Accordingly, the embodiments expressed in the present invention are not intended to limit the technical idea of the present invention, but to illustrate, and the scope of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas equivalent to or within the scope of the present invention should be construed as being included in the scope of the present invention.

Various embodiments have been described in the best mode for carrying out the present invention.

The present invention is used in the related field of cameras to improve the accuracy of autofocus.

It is apparent to those skilled in the art that various changes and modifications are possible in the present invention without departing from the spirit or scope of the present invention. Accordingly, the present invention is intended to cover modifications and variations of the present invention provided within the appended claims and their equivalents.

Claims (20)

1. From the camera,

   A lens that collects or radiates light from a subject to form an optical image;

   An image sensor that processes a first image corresponding to the subject;

   An auto focus actuator for adjusting the focus applied to the image sensor by moving the lens up and down; And

   Acquiring phase detection auto focus data (hereinafter, PDAF data) from the image sensor while performing an auto focus algorithm operation,

   When the reliability of the acquired PDAF data is equal to or greater than a preset threshold, the autofocus actuator controls the lens to move by a first predetermined distance,

   When the reliability of the PDAF data is less than a preset threshold, the control unit rotates the image sensor by a predetermined angle in the first direction

   Camera comprising a.
2. The method of claim 1, wherein the control unit

   If the reliability of the PDAF data is less than a preset threshold, check whether the image sensor can be rotated,

   If the image sensor can be rotated, the image sensor rotation autofocus algorithm is executed,

   If the image sensor cannot be rotated, executing a contrast auto focus algorithm,

   camera.
3. The method of claim 1, wherein the control unit

   Determining the reliability of the PDAF based on the defocust accuracy of the PDAF data and a contrast detection value through a horizontal edge filter,

   camera.
4. The method of claim 1, wherein the control unit

   Rotating the image sensor in a rotational direction around an axis in a horizontal plane parallel to the movement direction of the lens,

   camera.
5. The method of claim 2, wherein the control unit

   If the image sensor cannot be rotated, check the contrast data at the current position of the lens,

   Determine the moving direction of the lens based on the confirmed contrast data,

   Controlling the autofocus actuator to move the lens by a first distance in a second direction corresponding to the determined moving direction,

   If the previous focus value is greater than or equal to the current focus value, controlling the autofocus actuator to move the lens by the first distance in a direction opposite to the second direction,

   camera.
6. The method of claim 5, wherein the control unit

   If the focus value is less than the current focus value, reconfirming contrast data at the current position of the lens,

   camera.
7. The method of claim 2, wherein the control unit

   Rotate the image sensor by a predetermined angle in the first direction,

   Acquire PDAF data again from the image sensor,

   When the reliability of the acquired PDAF data is equal to or greater than a preset threshold, the autofocus actuator moves the lens by a second predetermined distance,

   Rotating the image sensor by a predetermined angle in a direction opposite to the first direction,

   camera.
8. The method of claim 7, wherein the control unit

   If the reliability of the obtained PDAF data is less than a preset threshold, executing a contrast auto-focus algorithm,

   camera.
9. The method of claim 7, wherein the control unit

   Skipping the image frame corresponding to the time while the image sensor is rotating,

   camera.
10. The method of claim 7, wherein the control unit

    Rotate the first image by a predetermined angle in a direction opposite to the first direction,

    Displaying the rotated first image on a preview screen,

    camera.
11. In the camera control method,

    Processing a first image corresponding to the subject;

    Acquiring phase detection auto focus data (hereinafter, PDAF data) from an image sensor while performing an Auto Focus Algorithm operation;

    When the reliability of the acquired PDAF data is equal to or greater than a preset threshold, controlling the autofocus actuator to move the lens by a first predetermined distance; and

    If the reliability of the PDAF data is less than a preset threshold, rotating the image sensor by a predetermined angle in the first direction

    Camera control method comprising a.
12. The method of claim 11,

    Checking whether the image sensor can be rotated if the reliability of the PDAF data is less than a preset threshold;

    If the image sensor can be rotated, executing an image sensor rotation auto focus algorithm; And,

    If the image sensor cannot be rotated, further comprising executing a contrast autofocus algorithm,

    Camera control method.
13. The method of claim 11,

    The step of determining the reliability of the PDAF based on the defocust accuracy of the PDAF data and a contrast detection value through a horizontal edge filter,

    Camera control method.
14. The method of claim 11,

    Rotating the image sensor in a rotational direction around an axis in a horizontal plane parallel to the moving direction of the lens,

    Camera control method.
15. The method of claim 12,

    Checking contrast data at a current position of the lens when the image sensor cannot be rotated;

    Determining a moving direction of the lens based on the checked contrast data;

    Controlling the auto focus actuator to move the lens by a first distance in a second direction corresponding to a determined moving direction; And

    If the previous focus value is greater than or equal to the current focus value, controlling the autofocus actuator to move the lens by the first distance in a direction opposite to the second direction,

    Camera control method.
16. The method of claim 15,

    If the focus value is less than the current focus value, further comprising reconfirming contrast data at the current position of the lens,

    Camera control method.
17. The method of claim 12,

    Rotating the image sensor by a predetermined angle in a first direction;

    Acquiring PDAF data again from the image sensor;

    If the obtained reliability of the PDAF data is greater than or equal to a preset threshold, the autofocus actuator moves the lens by a second predetermined distance; And

    Further comprising rotating the image sensor by a predetermined angle in a direction opposite to the first direction,

    Camera control method.
18. The method of claim 17,

    If the reliability of the obtained PDAF data is less than a preset threshold, further comprising the step of executing a contrast auto-focus algorithm,

    Camera control method.
19. The method of claim 17,

    Further comprising the step of skipping the image frame corresponding to the time during the rotation of the image sensor,

    Camera control method.
20. The method of claim 17,

    Rotating the first image by a predetermined angle in a direction opposite to the first direction;

    Further comprising the step of displaying the rotated first image on a preview screen,

    Camera control method.

Images