Patent Description:
A display device is a device having a function of receiving, processing, and displaying a video that a user may watch. For example, the display device receives a broadcast selected by the user from broadcast signals transmitted from a broadcasting station, separates a video signal from the received signals, and displays the separated video signal on a display.

In recent years, because of a development of a broadcasting technology and a network technology, functions of the display device have also been considerably diversified, and a performance of the device has been improved accordingly. That is, the display device has been developed to provide not only broadcast contents but also various other contents to the user. For example, the display device may provide game play, music listening, internet shopping, user customized information, and the like using various applications as well as programs received from the broadcasting station. In order to perform such extended functions, the display device may be basically connected to other devices or networks using various communication protocols, and may provide the user with an ubiquitous computing environment. In other words, the display device has evolved into a smart device that enables connectivity to a network and continuous computing.

Recently, a flexible display, which has sufficient elasticity, and thus, be able to be deformed largely, has been developed. A size of the mobile terminal may be varied using a deforming property of the flexible display. When twisting or excessive deformation occurs in the mobile terminal having such a variable structure, a defect may occur in the mobile terminal. Thus, a change of the structure of the mobile terminal should be performed stably.

In addition, in order to show an intended content or screen to the user, the mobile terminal needs to orient the content or screen on the display of such changing shape. Furthermore, the mobile terminal may need to further adjust the oriented content in consideration of an extension direction and the orientation. <CIT> relates to a mobile terminal having <NUM> axis slide detector and method for operating mobile terminal using <NUM> axis slide detector. <CIT> relates to recognizing device of slide type terminal. <CIT> relates to a display expansion type mobile terminal with sliding motion.

One purpose of the present disclosure is to provide a mobile terminal that may prevent distortion of a frame through a sensor that detects degrees of extension and contraction of a flexible display unit, and may accurately adjust a size of a video output on the display unit.

One aspect of the present disclosure proposes a mobile terminal including a first frame, a second frame movable in a first direction or in a second direction opposite to the first direction with respect to the first frame, a slide rail extending in the first direction on the first frame, a slidably-moving portion coupled to the second frame and moving along the slide rail, a sensing terminal located on the slide rail, a sensing resistor connected to the sensing terminal, an input resistor positioned between a power supply unit and the sensing resistor, a detecting unit for measuring a voltage between the sensing resistor and the input resistor, a ground terminal located on the slidably-moving portion and facing the sensing terminal, and a controller that calculates a position of the second frame based on the voltage detected by the detecting unit when the ground terminal is in contact with the sensing terminal.

In one implementation, the slidably-moving portion may include a groove recessed in a face facing the slide rail, and the ground terminal may be located above the groove and in contact with the slide rail.

In one implementation, the ground terminal may include a conductive gasket made of an elastic material.

In one implementation, the mobile terminal may further include a flexible substrate having the sensing resistor and the input resistor formed thereon, and the sensing terminal may be mounted on the flexible substrate to be connected with the sensing resistor.

In one implementation, the sensing terminal may include a pogo pin having elasticity.

In one implementation, a plurality of sensing terminals may be arranged in the first direction, and a plurality of sensing resistors respectively connected to the plurality of sensing terminals may have different resistance values.

Another aspect of the present disclosure proposes a mobile terminal including a first frame, a second frame movable in a first direction or in a second direction opposite to the first direction with respect to the first frame, a flexible display unit including a fixed portion coupled to the first frame and a variable portion extending in the first direction and bent in a direction of a rear face of the second frame, a slide rail extending in the first direction on the second frame, a sensing terminal located on the slide rail, a sensing resistor connected to the sensing terminal, an input resistor positioned between a power supply unit and the sensing resistor, a detecting unit for measuring a voltage between the sensing resistor and the input resistor, a ground terminal coupled to a rear face of the flexible display unit and facing the sensing resistor, and a controller that calculates a position of the second frame based on the voltage detected by the detecting unit when the ground terminal is in contact with the sensing terminal.

In one implementation, the flexible display unit may include a display panel for outputting a video and a back plate for supporting a rear face of the display panel and containing a metal material, and the ground terminal may be connected to the back plate.

In one implementation, the mobile terminal may further include a third frame coupled to an end of the variable portion and moving in the first direction along the slide rail on a rear face of the second frame, and the ground terminal may be located on the second frame.

In one implementation, the sensing terminal may be located on a side face of the slide rail, and the ground terminal may extend vertically from the flexible display unit.

The mobile terminal that detects the moved distance of the frame and controls the driving unit to move the frame stably without the distortion may be provided.

In addition, since the size of the video output on the display unit may be accurately adjusted, usability may be improved.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by illustration only.

Description will now be given in detail according to exemplary embodiments disclosed herein, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components may be provided with the same reference numbers, and description thereof will not be repeated. In general, a suffix such as "module" and "unit" may be used to refer to elements or components. Use of such a suffix herein is merely intended to facilitate description of the specification, and the suffix itself is not intended to give any special meaning or function. In the present disclosure, that which is well-known to one of ordinary skill in the relevant art has generally been omitted for the sake of brevity. The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings.

It will be understood that when an element is referred to as being "connected with" another element, the element can be directly connected with the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly connected with" another element, there are no intervening elements present.

The terminology used in the present disclosure is used only to describe specific embodiments, not intended to limit the present disclosure.

The mobile terminal <NUM> is shown having components such as a wireless communication unit <NUM>, an input unit <NUM>, a sensing unit <NUM>, an output unit <NUM>, an interface unit <NUM>, a memory <NUM>, a controller <NUM>, and a power supply unit <NUM>. Referring now to <FIG>, the mobile terminal <NUM> is shown having wireless communication unit <NUM> configured with several commonly implemented components. It is understood that implementing all of the illustrated components is not a requirement, and that greater or fewer components may alternatively be implemented.

The mobile communication module <NUM> can transmit and/or receive wireless signals to and from one or more network entities. Typical examples of a network entity include a base station, an external mobile terminal, a server, and the like. Such network entities form part of a mobile communication network, which is constructed according to technical standards or communication methods for mobile communications (for example, Global System for Mobile Communication (GSM), Code Division Multi Access (CDMA), CDMA2000(Code Division Multi Access <NUM>), EV-DO(Enhanced Voice-Data Optimized or Enhanced Voice-Data Only), Wideband CDMA (WCDMA), High Speed Downlink Packet access (HSDPA), HSUPA(High Speed Uplink Packet Access), Long Term Evolution (LTE) , LTE-A(Long Term Evolution-Advanced), and the like).

Examples of such wireless Internet access include Wireless LAN (WLAN), Wireless Fidelity (Wi-Fi), Wi-Fi Direct, Digital Living Network Alliance (DLNA), Wireless Broadband (WiBro), Worldwide Interoperability for Microwave Access (WiMAX), High Speed Downlink Packet Access (HSDPA), HSUPA (High Speed Uplink Packet Access), Long Term Evolution (LTE), LTE-A (Long Term Evolution-Advanced), and the like.

In some embodiments, when the wireless Internet access is implemented according to, for example, WiBro, HSDPA, HSUPA, GSM, CDMA, WCDMA, LTE, LTE-A and the like, as part of a mobile communication network, the wireless Internet module <NUM> performs such wireless Internet access.

Suitable technologies for implementing such short-range communications include BLUETOOTHTM, Radio Frequency IDentification (RFID), Infrared Data Association (IrDA), Ultra-WideBand (UWB), ZigBee, Near Field Communication (NFC), Wireless-Fidelity (Wi-Fi), Wi-Fi Direct, Wireless USB (Wireless Universal Serial Bus), and the like.

Such cameras <NUM> may process image frames of still pictures or video obtained by image sensors in a video or image capture mode. The processed image frames can be displayed on the display unit <NUM> or stored in memory <NUM>. In some cases, the cameras <NUM> may be arranged in a matrix configuration to permit a plurality of images having various angles or focal points to be input to the mobile terminal <NUM>. As another example, the cameras <NUM> may be located in a stereoscopic arrangement to acquire left and right images for implementing a stereoscopic image.

The sensing unit <NUM> is typically implemented using one or more sensors configured to sense internal information of the mobile terminal, the surrounding environment of the mobile terminal, user information, and the like. For example,, the sensing unit <NUM> may alternatively or additionally include other types of sensors or devices, such as a proximity sensor <NUM> and an illumination sensor <NUM>, a touch sensor, an acceleration sensor, a magnetic sensor, a G-sensor, a gyroscope sensor, a motion sensor, an RGB sensor, an infrared (IR) sensor, a finger scan sensor, a ultrasonic sensor, an optical sensor (for example, camera <NUM>), a microphone <NUM>, a battery gauge, an environment sensor (for example, a barometer, a hygrometer, a thermometer, a radiation detection sensor, a thermal sensor, and a gas sensor, among others), and a chemical sensor (for example, an electronic nose, a health care sensor, a biometric sensor, and the like), to name a few. The mobile terminal <NUM> may be configured to utilize information obtained from sensing unit <NUM>, and in particular, information obtained from one or more sensors of the sensing unit <NUM>, and combinations thereof.

The controller <NUM> typically functions to control overall operation of the mobile terminal <NUM>, in addition to the operations associated with the application programs. The controller <NUM> may provide or process information or functions appropriate for a user by processing signals, data, information and the like, which are input or output, or activating application programs stored in the memory <NUM>.

To drive the application programs stored in the memory <NUM>, the controller <NUM> may be implemented to control a predetermined number of the components mentioned above in reference with FIG. Moreover, the controller <NUM> may be implemented to combinedly operate two or more of the components provided in the mobile terminal <NUM> to drive the application programs.

<FIG> is an expanded perspective view of a mobile terminal according to one embodiment. Further, <FIG> shows perspective views respectively illustrating a first state and a second state viewed from one side of a mobile terminal according to one embodiment. Further, <FIG> shows rear face views respectively illustrating a first state and a second state of a mobile terminal according to one embodiment. Further, <FIG> shows cross-sectional views respectively taken along a line A-A and a line B-B of <FIG>. In these drawings, <FIG>, <FIG>, and <FIG>show a first state of the mobile terminal, and <FIG>, <FIG>, and <FIG> show a second state of the mobile terminal.

As shown, a mobile terminal <NUM> in a first state is contracted, and has a smaller size than the mobile terminal <NUM> in a second state. In addition, a size of a display unit <NUM> located disposed on a front face of the mobile terminal <NUM> also becomes smaller than that of the display unit <NUM> in the second state. The mobile terminal <NUM> of the first state is expanded in a first direction D1 to be in the second state. In the second state, the size of the mobile terminal <NUM> and a size of a front face of the display unit <NUM> are larger than those in the first state. In a following description, a direction in which the mobile terminal <NUM> and the display <NUM> thereof are extended or enlarged is referred to as a first direction D1, a direction in which the mobile terminal <NUM> and the display <NUM> thereof are contracted or retracted, or reduce to be converted into the first state from the second state is referred to as a second direction D2, and a direction perpendicular to the first and second directions D1 and D2 is referred to as a third direction.

The mobile terminal <NUM> of the present disclosure may be converted from the first state in which the display unit <NUM> is positioned on the front face of a bar-shaped mobile terminal as shown in <FIG> into the second state as shown in <FIG> by enlarging a screen thereof. In the second state, an area of the front face of the display unit <NUM> is enlarged, and an area of a rear face of the display unit <NUM> is reduced as shown in <FIG>. That is, the display unit <NUM> positioned on a rear face of the mobile terminal <NUM> in the first state moves to the front face of the mobile terminal <NUM> in the second state.

As such, the display unit may use a flexible display unit <NUM> that may be bent such that the position of the display unit may be varied. The flexible display is a lightweight, unbreakable, and durable display that is built on a thin and flexible substrate that may be bent, crooked, folded, twisted, or rolled while retaining properties of a conventional flat panel display.

In addition, an electronic paper is a display technology to which properties of general ink are applied. The electronic paper may be different from the conventional flat panel display in using reflected light. The electronic paper may change information using a twisted ball or electrophoresis using a capsule.

In a state in which the flexible display unit <NUM> is not deformed (e.g., a state of having an infinite curvature radius, hereinafter referred to as a basic state), a display region of the flexible display unit <NUM> becomes flat. In a state in which the flexible display unit <NUM> is deformed by an external force from the basic state (e.g., a state of having a finite radius of curvature, hereinafter referred to as a deformed state), the display region may become a curved face. As shown, information displayed in the deformation state may be visual information output on the curved face. Such visual information is implemented by independently controlling light emission of sub-pixels arranged in a matrix. The sub-pixel refers to a minimum unit for implementing one color.

The flexible display unit <NUM> may be in a curved state (e.g., a vertically or horizontally curved state) rather than a flat state in the basic state. In this case, when the external force is applied to the flexible display unit <NUM>, the flexible display unit <NUM> may be deformed into the flat state (or a less curved state) or more curved state.

The flexible display unit <NUM> may be combined with a touch sensor to implement a flexible touch screen. When a touch is made on the flexible touch screen, the controller <NUM> (see <FIG>) may perform control corresponding to such touch input. The flexible touch screen may be configured to detect the touch input in the deformed state as well as in the basic state.

The touch sensor detects the touch (or touch input) applied on the touch screen using at least one of various touch schemes such as a resistive film scheme, a capacitance scheme, an infrared scheme, an ultrasonic wave scheme, a magnetic field scheme, and the like.

As an example, the touch sensor may be configured to convert a change in pressure applied on a specific portion of the touch screen capacitance generated at the specific portion, or the like into an electrical input signal. The touch sensor may be configured such that a touch object applying a touch on the touch screen may detect touched position and area on the touch sensor, a pressure during the touch, a capacitance during the touch, and the like.

Further, the mobile terminal <NUM> may have a deformation detection means for detecting the deformation of the flexible display unit <NUM>. Such deformation detection means may be included in the sensing unit <NUM> (see <FIG>).

The deformation detection means may be disposed in the flexible display unit <NUM> or a case (first to third frames <NUM> to <NUM> to be described later) to detect information related to the deformation of the flexible display unit <NUM>. In this connection, the information related to the deformation may include a direction in which the flexible display unit <NUM> is deformed, a degree of the deformation, a deformed position, a deformed time, an acceleration at which the deformed flexible display unit <NUM> is restored, and the like. In addition, the information related to the deformation may be various information that may be detected due to the bending of the flexible display unit <NUM>.

In addition, the controller <NUM> may change information displayed on the flexible display unit <NUM> or generate a control signal for controlling a function of the mobile terminal <NUM> based on the information related to the deformation of the flexible display unit <NUM> detected by the deformation detection means.

The state conversion (first or second state) of the flexible display unit <NUM>, i.e., the size change at the front and rear faces of the mobile terminal <NUM> of the display unit <NUM> based on the size change of the mobile terminal <NUM> may be performed manually by a force applied by the user, but may be not limited to such manual scheme. For example, when the mobile terminal <NUM> or the flexible display unit <NUM> is in the first state, the mobile terminal <NUM> or the flexible display unit <NUM> may be converted into the second state by the user or an application command without the external force applied by the user. As such, in order for the flexible display unit <NUM> to be automatically deformed without the external force, the mobile terminal <NUM> may include a driving unit <NUM> to be described later.

The flexible display unit <NUM> of the present disclosure is bent <NUM> degrees while being rolled on one of both sides of the mobile terminal <NUM>. Thus, a portion of the display unit <NUM> is disposed on the front face of the mobile terminal <NUM> based on such side, and the other portion thereof is disposed on the rear face of the mobile terminal <NUM>. A portion of the display unit <NUM> located on the front face of the mobile terminal <NUM> may be fixed to the front face so as not to move. Further, the other portion thereof located on the rear face of the mobile terminal <NUM> may be movable to the rear face.

In addition, the display unit <NUM> may be rolled on or released from the side. Accordingly, the portion disposed on the rear face of the mobile terminal <NUM> moves, so that the size of the portion disposed on the front face of the mobile terminal <NUM> may be adjusted. Since the area of the flexible display unit <NUM> is determined and the flexible display unit <NUM> is formed of one continuous body, an area of the portion on the rear face decreases as an area of the portion on the front face increases. Such a display unit <NUM> may be rolled in a second frame <NUM>, which is movable relative to a first frame <NUM> to be described later, more correctly, on one of sides of the second frame <NUM>. The display unit <NUM> may be withdrawn or pulled out from or inserted or pushed into the second frame <NUM> while being rolled in the second frame <NUM> along a moving direction of the second frame <NUM> to adjust the area of the display unit <NUM> on the front face of the mobile terminal <NUM>. Such operation will be described in more detail below along with other relevant components of the mobile terminal <NUM>.

Typically, an antenna is disposed in the case or the housing of the mobile terminal <NUM>, but a portion where the antenna is installed in the case or the housing may be limited because of the flexible display unit <NUM> that covers not only the front face of the mobile terminal <NUM> but also the rear face thereof. For this reason, the antenna may be implemented on the flexible display unit <NUM>. An antenna on display (AOD) is an antenna in which a transparent film is formed by stacking an electrode layer and a dielectric layer that have patterns engraved thereon, respectively. The antenna on display may be implemented thinner than an antenna implemented using a laser direct structuring (LDS) technology using a conventional copper nickel plating scheme, so that the antenna on display may not be exposed to the outside without affecting a thickness. In addition, the antenna on display may transmit and receive a signal directly to or from the display unit <NUM>. Accordingly, the antenna on display may be used in the mobile terminal <NUM> in which the display unit <NUM> is located on the both faces of the mobile terminal <NUM> as in the present disclosure.

With reference to <FIG>, a detailed configuration of the mobile terminal <NUM> of the present disclosure will be described in detail below. A following description will be achieved basically with reference to <FIG> illustrating an overall configuration. <FIG> are referred to explain detailed features of corresponding components in the first and second states of the mobile terminal <NUM>.

The mobile terminal <NUM> of the present disclosure includes a main frame in which components are mounted, and the main frame of the present disclosure may vary in size in the first direction as shown in <FIG>. One or more frames move relative to each other, and sizes thereof may vary in the first direction. Electronic components are mounted in the main frame, and the flexible display unit <NUM> is located out of the main frame.

Since the mobile terminal <NUM> of the present disclosure includes the flexible display unit, the flexible display unit <NUM> may be combined in a form surrounding a front face and a rear face of the main frame. The main frame may include first to third frames <NUM> to <NUM>. The main frame may include the first frame <NUM>, the second frame <NUM> moving in the first direction with respect to the first frame <NUM>, and the third frame <NUM> moving in the first direction with respect to the second frame <NUM>. The first frame <NUM> and the second frame <NUM> include front portions, a rear portions, and side portions, respectively, and are coupled to each other. Thus, the mobile terminal <NUM> may have a hexahedral outer shape by such coupled first and second frames <NUM> and <NUM>. In consideration of an illustrated configuration of the first to third frames <NUM> to <NUM>, movements of the second and third frames <NUM> and <NUM> may be a slide movement.

First, the first frame <NUM> corresponds to a main body of the mobile terminal <NUM>, and may have a space therein for accommodating various components. In addition, the first frame <NUM> may accommodate the second frame <NUM> movably coupled to the first frame <NUM> in such a space. More specifically, as shown in <FIG> and <FIG>, the first frame <NUM> may include a first front portion <NUM> disposed at a front portion of the mobile terminal <NUM> and a first rear portion <NUM> and a second rear portion <NUM> disposed at a rear portion of the mobile terminal.

Such first front portion <NUM>, first rear portion <NUM>, and second rear portion <NUM> may be respectively formed of plate-shaped members that are generally flat. The first rear portion <NUM> and the second rear portion <NUM> may be respectively formed of separate members coupled to each other or may be formed of one member as shown. The first front portion <NUM> and the first rear portion/second rear portion <NUM> and <NUM> may be spaced apart from each other at a predetermined spacing to define a predetermined space therebetween, and may be connected to each other by a side portion <NUM>. The controller <NUM> and the power supply unit <NUM> may be accommodated as components of the mobile terminal <NUM> in the space in the first frame <NUM>. For example, the controller <NUM> may be a circuit board including a processor and an electronic circuit for controlling the operation of the mobile terminal, and the power supply unit <NUM> may be a battery and related components. In addition, the second frame <NUM> and the driving unit <NUM> to described later may also be accommodated in the first frame <NUM>.

As described above, the display unit <NUM> has the continuous body, and thus, may be disposed on both the front face and the rear face of the mobile terminal <NUM> while being rolled in the mobile terminal <NUM>. The display unit <NUM> may include the front face positioned at the front face of the mobile terminal <NUM>, the rear face positioned at the rear face of the mobile terminal <NUM>, and the side face positioned between the front face and the rear face thereof and surrounding the side face of the mobile terminal. The front face and the rear face of the display unit <NUM> are flat, and the side face of the display unit <NUM> may form a curved face. When the flexible display unit <NUM> may be damaged when being bent. Thus, the flexible display unit <NUM> may be formed to be bent with a predetermined curvature.

The display unit <NUM> may be divided into a fixed portion and a variable portion. The fixed portion means a portion fixed to the frame. Because of being fixed to the frame, the fixed portion maintains a constant shape without changing a bending degree. On the other hand, the variable portion means a portion in which a bending angle or a position of the bent portion changes. The variable portion in which the position or bending angle of the bent portion changes requires a structure for supporting a rear face of the variable portion in response to the change.

A first region of the display unit <NUM> may be coupled to the first front portion <NUM> corresponding to the front face of the mobile terminal <NUM>.

In one example, as shown in <FIG>, various physical input units <NUM> for manipulation of the mobile terminal <NUM> and sensing units <NUM> may be located on the first rear portion <NUM>, and the display unit <NUM> may be disposed only on the second rear portion <NUM>. Since the first rear portion <NUM> does not overlap the flexible display unit <NUM> regardless of the state of the mobile terminal, and is always exposed to the outside, the input unit <NUM> such as various buttons, switches, the camera <NUM>, and a flash, and the sensing unit <NUM> such as a proximity sensor <NUM> may be arranged on the first rear portion <NUM>. In a conventional bar-shaped terminal, a display unit is provided only on a front face of the terminal. Therefore, a main camera is placed on a rear face of the terminal in order for the user to capture an object at an opposite side while looking through the display unit. On the other hand, an additional auxiliary camera is required to be disposed on the front face of the terminal in order for the user to capture himself or herself while viewing himself or herself through the display unit.

However, the display unit <NUM> is positioned at both the front face and the rear face of the mobile terminal <NUM> of the present disclosure. Therefore, when the user captures himself or herself, a display unit on the same face as the camera <NUM>, that is, the portion of the display <NUM> on the rear face of the mobile terminal <NUM> in the drawing may be used. Further, when the user captures the object on the opposite side of the user, a display unit on the opposite face of the camera <NUM>, that is, the portion of the display unit <NUM> on the front face of the mobile terminal <NUM> in the drawing may be used. For this reason, the mobile terminal <NUM> may capture the object on the opposite side of the user and capture the user using the single camera <NUM>. The camera may include a plurality of cameras having different angles of view, such as wide angle, super wide angle, and telephotographic cameras. In addition to the camera, a proximity sensor sound output unit may be positioned on the first rear portion <NUM>, and an antenna <NUM> may be installed on the first rear portion <NUM>.

The side portion <NUM> may extend along edges of the first front portion <NUM> and the first rear portion/second rear portion <NUM> and <NUM> to surround the first frame <NUM>, and may form the outer shape of the mobile terminal <NUM>. However, as mentioned above, since the second frame <NUM> is accommodated in the first frame <NUM> and is movably coupled thereto, in order to allow the movement of the second frame <NUM> relative to the first frame <NUM>, a portion of the first frame <NUM> needs to be opened. As shown in <FIG>, as an example, the second frame <NUM> is movably coupled to one of both side portions of the first frame <NUM>, so that the side portion <NUM> may not be formed on the same side portion, and thus, the portion of the first frame <NUM> may be opened. Accordingly, the first frame <NUM> may include a substantially closed first side portion 101a and a second side portion 101b, which is disposed to be opposite to the first side portion 101a and is opened. The side portion <NUM> is exposed to the outside of the mobile terminal <NUM>, so that an interface unit <NUM> for connecting a supply port or an ear jack, the user input unit <NUM> such as a volume button, or the like may be disposed on the side portion <NUM>. When containing a metal material, the side portion <NUM> may serve as an antenna.

The second rear portion <NUM> of the first frame <NUM> may be covered by the display unit, but may be disposed on the front face of the display unit using a transparent material.

The second frame <NUM> may include a second front portion <NUM> disposed at the front portion of the mobile terminal <NUM> and a third rear portion <NUM> disposed at the rear portion of the mobile terminal <NUM>. Like the first front portion <NUM> and the first rear portion <NUM> of the first frame <NUM>, the second front portion <NUM> and the third rear portion <NUM> may be formed of plate-shaped members that are generally flat. In addition, the second frame <NUM> also accommodates various components, and must not interfere with the components accommodated in the first frame <NUM> during the movement. Accordingly, the second front portion <NUM> and the third rear portion <NUM> may be coupled to each other in a state of being spaced apart from each other to define a predetermined space therebetween, and may have shapes that do not interfere with the components in the first frame <NUM>.

In addition, the display unit <NUM> may be bent <NUM> degrees while being rolled in the second frame <NUM> to be disposed on both the front face and the rear face of the mobile terminal <NUM>. For such an arrangement of the display unit <NUM>, the second frame <NUM> may include a roller <NUM> rotatably disposed therein. The roller <NUM> may be disposed at any position inside the second frame <NUM>. However, the display unit <NUM> should be spread flat on the front face and the rear face of the mobile terminal <NUM> to provide a good quality screen to the user. Further, for such spread, a proper tension must be provided on the display unit <NUM>. In order to provide the proper tension, the roller <NUM> may be disposed at a first directional end of the second frame <NUM>. The roller <NUM> may extend in the third direction, and may be rotatably coupled to the second frame <NUM>.

The display unit <NUM> may be rolled around the roller <NUM> while being gently bent with a predetermined curvature. The flexible display unit <NUM> may include a first face on which a video is output and exposed to the outside and an inner face facing the frame at the opposite side. The roller <NUM> may be installed to rotate freely in the second frame <NUM> while being in contact with the inner face of the display unit <NUM>. Accordingly, the roller <NUM> may actually move the display unit <NUM> in a lateral direction of the mobile terminal <NUM>, that is, in a direction perpendicular to a longitudinal direction. As will be described later, when the second frame <NUM> slides, because of the tension applied by the second frame <NUM>, the display unit <NUM> moves to the front face or the rear face of the mobile terminal <NUM> in different directions (i.e., the first direction D1 or the second direction D2) relative to the second frame <NUM>. The roller <NUM> may guide such movement while rotating.

In addition, the roller <NUM> is disposed on a first side portion 102a of the second frame <NUM>, and the first side portion 102a actually corresponds to an outermost side portion of the mobile terminal <NUM>. When the first side portion 102a of the second frame <NUM> is exposed, the display unit <NUM> rolled on the roller <NUM> may be damaged. Accordingly, the second frame <NUM> may include a side frame <NUM> disposed on the first side portion 102a.

The side frame <NUM> extends in the longitudinal direction of the second frame <NUM> to cover the first side portion 102a, thereby protecting the roller <NUM> and the display unit <NUM> rolled thereon. That is, the side frame <NUM> covers the side face of the display unit <NUM>, and the side face thereof is located in the third region. The first to third regions are at specified positions on the flexible display unit and do not change in size or position, but the sizes of the front face and the rear face, and the position of the side face are determined based on the state of the main frame. The first region and the second region correspond to the fixed portion described above, and the third region corresponds to the variable portion described above.

The third region may vary in position depending on the state of the mobile terminal. Because the side face is rolled by the roller, the side face is bent with the predetermined curvature, and an inner face of the side frame may include a curved face corresponding to the curvature of the side face.

Because of the side frame <NUM>, the second frame <NUM> may have the substantially closed first side portion 102a, and the side frame <NUM> may substantially form the outer shape of the mobile terminal <NUM> together with the side face <NUM> of the first frame <NUM>. In addition, the second frame <NUM> may include a second side portion 102b that is disposed opposite the first side portion 102a to minimize interference with the components within the first frame <NUM> during the movement, and is opened.

Such a second frame <NUM> is movably coupled to the first frame <NUM>, and thus may slide in the predetermined first or second direction D1 or D2 relative to the first frame <NUM>. More specifically, the second frame <NUM> may be movably coupled to the first frame <NUM> through the side portion of the first frame <NUM>, more precisely, through the opened second side portion 101b, as shown. More specifically, the second side portion 102b of the second frame is disposed relatively adjacent to the first side portion 101a of the first frame <NUM> which is closed. Accordingly, the first side portion 102a of the second frame may be disposed to be opposite to the first side portion 101a. Accordingly, the second side portion 102b is inserted into the first frame <NUM> through the side portion of the first frame, that is, the second side portion 101b thereof. The first side portion 102a is not inserted into the first frame <NUM> but is always located outside the first frame <NUM>, thereby forming the outer shape of the mobile terminal <NUM> as described above. However, when necessary, such first side portion 102b of the second frame <NUM> may also be inserted into the first frame <NUM>.

Because of such positional relationship, the second frame <NUM> may extend from or contract to the first frame <NUM> in a direction perpendicular to the longitudinal direction of the mobile terminal <NUM> or the first frame <NUM>. That is, the first and second directions D1 and D2 may basically be directions perpendicular to the longitudinal direction of the mobile terminal <NUM> or the first frame <NUM>. Further, the first and second directions D1 and D2 may also be described as the lateral direction or the horizontal direction of the mobile terminal <NUM> or the first frame <NUM>. In addition, during the movement in the first direction D1, the second frame <NUM> extends from the first frame <NUM>. Accordingly, the first direction D1 may be a direction in which the second frame <NUM> moves away from the first frame <NUM>, that is, moves outwardly of the mobile terminal <NUM> or the first frame <NUM>. On the other hand, during the movement in the second direction D2, the second frame <NUM> contracts to the first frame <NUM>. Thus, the second direction D2 is a direction opposite to the first direction D1, so that the second direction D2 may be a direction in which the second frame <NUM> moves to become closer to the first frame <NUM>, that is, moves inwardly of the mobile terminal <NUM> or the first frame <NUM>. When being moved in the first direction D1, such second frame <NUM> extends and applies a force to the portion of the display unit <NUM> disposed on the rear face of the mobile terminal <NUM>, so that the portion of the display unit <NUM> may be disposed on the front face of the mobile terminal <NUM>, and a region for such additional arrangement may be defined. Thus, the second frame <NUM> may convert the mobile terminal <NUM> into the second state with the display unit <NUM> with the relatively extended front face by moving in the first direction D1. On the other hand, when being moved in the second direction D2, the second frame <NUM> contracts into an original state thereof, and applies a force to the portion of the display unit <NUM> disposed on the front face of the mobile terminal <NUM> to return to the rear face of the mobile terminal <NUM> again. Thus, the second frame <NUM> may convert the mobile terminal <NUM> into the first state with the display unit <NUM> with the relatively contracted front face by moving in the second direction D2. Accordingly, the second frame <NUM> selectively exposes the display unit <NUM> to the front face of the mobile terminal <NUM> depending on the moving direction (i.e., the first or second direction D1 and D2). Accordingly, the mobile terminal <NUM> may be converted into the first or second state defined above.

During the expansion and the contraction in such first and second directions D1 and D2, the second frame <NUM> may overlap the first frame <NUM>, more precisely, the first front portion <NUM> and the first rear portion <NUM> thereof so as not to interfere with the first frame <NUM>. More specifically, the display unit <NUM> may be coupled to and supported by the first front portion <NUM> of the first frame <NUM>, as described above. Accordingly, the display unit <NUM> does not need to be additionally supported by the second front portion <NUM> of the second frame <NUM>. Rather, when the second front portion <NUM> is interposed between the first front portion <NUM> and the display unit <NUM>, the display unit <NUM> may be deformed or damaged because of friction with the second front portion <NUM>, which is repeatedly moved. Thus, the second front portion <NUM> may be disposed below the first front portion <NUM>, as shown in <FIG>. That is, a front face of the second front portion <NUM> may face the rear face of the first front portion <NUM>. In addition, the rear face of the first front portion <NUM> may be in contact with the front face of the second front portion <NUM> to stably support the movement of the second frame <NUM>.

The third rear portion <NUM> of the second frame <NUM> may be disposed below the second rear portion <NUM> of the first frame <NUM>. That is, the front face of the third rear portion <NUM> may face the rear face of the second rear portion <NUM>. In addition, the rear face of the second rear portion <NUM> may be in contact with the front face of the third rear portion <NUM> to stably support the movement of the second frame <NUM>. Because of such arrangement, the third rear portion <NUM> may be exposed to the outside of the first frame, more precisely, of the second rear portion <NUM>, and may be coupled to the display unit <NUM>.

Alternatively, when the second rear portion <NUM> is made of a transparent material, the second rear portion <NUM> may form an outer shape of the rear face of the mobile terminal. The second rear portion <NUM> may be positioned rearward of the third rear portion <NUM> of the second frame, and the flexible display unit may be disposed between the second rear portion <NUM> and the third rear portion <NUM> in the first state.

When the second rear portion <NUM> is made of a material such as a transparent glass to form the outer shape of the rear face of the mobile terminal, the first rear portion <NUM> may be implemented using the same member as the second rear portion <NUM>. That is, the camera <NUM>, the flash or the sensing unit <NUM>, and the like may be arranged by partially coating the plate-shaped member of the transparent glass material to not allow the internal components to be visible and by not coating only a required portion.

In addition, the second frame <NUM> may expand and contract the size of the mobile terminal <NUM> itself, particularly the front face of the mobile terminal <NUM> by the expansion and the contraction in the first and second directions D1 and D2. Thus, the display unit <NUM> must move by such extended or reduced front face size to obtain the intended first and second states. However, when being fixed to the second frame <NUM>, the display unit <NUM> may not be moved smoothly to be adapted for the front face of the mobile terminal <NUM> that is expanded or contracted. For this reason, the display unit <NUM> may be movably coupled to the second frame <NUM>. More specifically, the display unit <NUM> may include a first side edge (or side end) 151d disposed on the front face of the mobile terminal <NUM> and a second side edge 151e opposite to the first side edge 151d and disposed on the rear face of the mobile terminal <NUM>. The first side edge <NUM> may be disposed on the front face of the first frame <NUM>, that is, the front face of the first front portion <NUM> thereof, and may be disposed adjacent to the side portion of the mobile terminal <NUM>, that is, the first side portion 101a of the first frame. On the other hand, since the second side edge 151e is adjacent to the rear face of the mobile terminal <NUM> and the third rear portion <NUM> of the second frame <NUM>, the second side edge 151e may is be coupled the third rear portion <NUM> of the second frame <NUM> to be movable in the first and second directions D1 and D2. In addition, since the display unit <NUM> is not structurally strong, a third frame <NUM> may be coupled to the second side edge 151e. The third frame <NUM> may be formed of a plate-shaped member extending in the longitudinal direction of the mobile terminal <NUM>. Accordingly, the third frame <NUM> may be coupled to the second frame, that is, the third rear portion <NUM> thereof to be movable in the first and second directions D1 and D2 instead of the second side edge 151e. In addition, the second frame <NUM> may include a slot <NUM> extending in the lateral direction of the mobile terminal <NUM> or the second frame <NUM>, that is, the direction perpendicular to the longitudinal direction thereof. Further, the third frame <NUM> may be stably moved while being guided by the slot <NUM>. The third frame <NUM> may include, for example, a projection inserted into the slot <NUM> for the movement along the slot <NUM>.

Referring to <FIG>, in connection with such configuration of the first to third frames <NUM>, <NUM>, and <NUM>, the display unit <NUM> may include a first region <NUM> extending from one side thereof, that is, the first side edge 151d toward the second side edge 151e by a predetermined length, and a second region <NUM> disposed opposite the first region <NUM>, and extending from the second side edge 151e toward the first side edge 151d by a predetermined length. In addition, the display unit <NUM> may include a third region <NUM> disposed between the first and second regions <NUM> and <NUM>. Such first to third regions <NUM>, <NUM>, and <NUM> may be connected to each other, and may form a continuous body of the display unit <NUM>. In addition, as described above, for the movement of the third region <NUM> toward the front face or the rear face of the mobile terminal <NUM> depending on the moving direction of the second frame <NUM>, the first region <NUM> may be fixed so as not to move to the front face of the mobile terminal <NUM>, and the second region <NUM> may be provided to be movable on the rear face of the mobile terminal. Such configuration of the display unit <NUM> will be described in more detail below.

The first region <NUM> may be disposed on the front face of the mobile terminal <NUM>, more specifically, the first frame <NUM>, that is, on the front face of the first front portion <NUM>. The first region <NUM> is fixed to the first frame <NUM>, that is, the front face of the first front portion <NUM> so as not to be moved during the movement of the second frame <NUM>, and thus, the first region <NUM> may always be exposed to the front face of the mobile terminal <NUM>. The third region <NUM> may be adjacent to the first region <NUM>, and may extend into the second frame <NUM> and rolled on the roller <NUM>. The third region <NUM> may consecutively extend out of the second frame <NUM> again and partially cover the second frame <NUM>, that is, the rear face of the third rear portion <NUM>. Further, the second frame <NUM>, that is, the third rear portion <NUM>, is adjacent to the first frame <NUM>, that is, the second rear portion <NUM> and together forms the rear case of the mobile terminal <NUM>, so that it may be described that the third region <NUM> is also disposed on the rear face of the first frame <NUM>.

The second region <NUM> may be adjacent to the third region <NUM> and may be disposed on the rear face of the mobile terminal <NUM>, more specifically, on the second frame, that is, the rear face of the third rear portion <NUM> thereof. The second region <NUM> may be coupled to the third frame <NUM> without being directly coupled to the second frame <NUM>. As shown in <FIG>, the slot <NUM> extending in the lateral direction (i.e., the direction perpendicular to the longitudinal direction of the mobile terminal <NUM>) to the second frame <NUM>, that is, to the third rear portion <NUM> is defined. Further, the third frame <NUM> may move along the slot <NUM>. In <FIG>, it is shown that the slot <NUM> is defined in the rear face of the second frame <NUM>, but may be defined in the side face of the second frame <NUM>. Although the second region <NUM> may move in the first or second direction D1 or D2 with respect to the second frame <NUM> together with the third frame <NUM>, the movement of the second region <NUM> may be restricted within the rear face of the mobile terminal <NUM> by the slot <NUM>. That is, the second region <NUM> does not move out of the second frame <NUM> even when the second frame <NUM> is extended or contracted, and may move along the slot <NUM> within the second frame <NUM> by the extended or contracted distance of the second frame <NUM>. Accordingly, the second region <NUM> may always be exposed to the rear face of the mobile terminal <NUM>.

As a result, the first region <NUM> may be disposed on the front face of the mobile terminal <NUM> and may be always exposed to the front face regardless of the movement of the second frame <NUM>, and the second region <NUM> may be disposed on the rear face of the mobile terminal <NUM> and may be always exposed to the rear face regardless of the movement of the second frame <NUM>. In addition, the third region <NUM> may be disposed between the first and second regions <NUM> and <NUM>, and may be selectively placed on the front face or the rear face of the mobile terminal <NUM> depending on the moving directions D1 and D2 of the second frame <NUM>.

Because of such selective placement of the third region <NUM>, as shown in <FIG>, the second rear portion <NUM> of the first frame <NUM> is covered by the second and third regions <NUM> and <NUM> and the third rear portion <NUM> of the display unit <NUM> in the first state, but the third region <NUM> moves to the front face of the mobile terminal <NUM> in the second state, and the third rear portion <NUM> also moves in the first direction D1, so that the mobile terminal <NUM> may be exposed to the outside. In addition, the second front portion <NUM> of the second frame <NUM> is disposed below the first front portion <NUM> of the first frame <NUM> in the first state, but is moved out of the first frame <NUM> and supports the third region <NUM> of the display unit <NUM> disposed on the front face of the mobile terminal <NUM> in the second state.

Since the first and second regions <NUM> and <NUM> are always respectively arranged on the front face and the rear face of the mobile terminal <NUM>, curvatures of the first region <NUM> and the second region <NUM> do not change, and the first region <NUM> and the second region <NUM> may be maintained in a flat basic state. However, the third region <NUM> may be rolled on the roller <NUM> and bent in the second frame <NUM>. When converting from the first state to the second state, the third region <NUM> may extend from the second frame <NUM> to the front face of the mobile terminal <NUM> while being rolled on the roller <NUM> in one direction. On the other hand, when converting from the second state to the first state, the third region <NUM> may be retracted from the front face of the mobile terminal <NUM> to the second frame <NUM> while being rolled on the roller <NUM> in the opposite direction, and at the same time, may return to the rear face of the mobile terminal <NUM> from the second frame <NUM>. A specific location of the foldable mobile terminal in a form of being spread like a book is easily damaged because only the specific location is folded repeatedly. On the other hand, the deformed portion of the flexible display unit <NUM>, that is, a portion rolled on the roller <NUM>, may vary based on the first and second states of the mobile terminal <NUM>, that is, the movement of the second frame <NUM>. Accordingly, the mobile terminal <NUM> of the present disclosure may significantly reduce deformation and fatigue repeatedly applied to a specific portion of the display unit <NUM>, thereby preventing damage to the display unit <NUM>.

Based on the above-described configuration, overall operations of the mobile terminal <NUM> will be described as follows. As an example, the state conversion may be performed manually by the user, and an operation of the mobile terminal <NUM> during such manual state conversion will be described. However, operations of the first to third frames <NUM> to <NUM> and the display unit <NUM>, which will be described below, may be performed in the same manner when a power source other than a user's force is used, for example, when the driving unit <NUM> to be described below is applied.

As shown in <FIG>, <FIG>, and <FIG>, the second frame <NUM> is fully retracted into the first frame <NUM> in the first state. Therefore, only the first region <NUM> of the display unit <NUM> fixed to the front face of the first frame <NUM> may be exposed to the front face of the mobile terminal <NUM>. Such first region <NUM> may be fixed and supported to the first frame <NUM>, that is, the first front portion <NUM> thereof. In addition, a major portion of the third region <NUM> may be disposed on the rear face of the mobile terminal <NUM> together with the second region <NUM>, and the third region <NUM> may be disposed in the second frame <NUM> while being partially rolled on the roller <NUM>. The third region <NUM> of the rear face of the mobile terminal <NUM> may be supported by the second frame, that is, the third rear portion <NUM> thereof. The second region <NUM> may be fixed by the third frame <NUM> disposed on the second frame (i.e., the third rear portion <NUM>) and may be movably coupled to the second frame <NUM>.

In such first state, when the second frame <NUM> moves in the first direction D1, the mobile terminal <NUM> may be converted into the second state. As shown in <FIG>, <FIG>, and <FIG>, the second frame <NUM> may extend from the first frame <NUM> by the movement in the first direction D1, and may increase the overall size of the mobile terminal <NUM>, in particular, the front face thereof. During the movement in the first direction D1, the second frame <NUM> may apply a force, that is, a tension, to the display unit <NUM> in the first direction D1. The display unit <NUM> is fixed to the first frame <NUM> but is coupled to the second frame <NUM> so as to be movable using the third frame <NUM>, so that the force applied by the second frame <NUM> allows the third region <NUM> to be rolled out from the roller <NUM> of the second frame <NUM> to the front face of the mobile terminal <NUM>. That is, the third region <NUM> may be withdrawn (or pulled out) from the second frame <NUM> or extend to (or move out of) the second frame <NUM>. At the same time, the third region <NUM>, particularly, the portion located on the rear face of the third region <NUM> may be rolled into the roller <NUM> of the second frame <NUM> from the rear face, or may be inserted (or pushed in), retracted, or moved into the second frame <NUM>. Not an entirety of the third region <NUM> is withdrawn from the second frame <NUM> to the front face of the mobile terminal <NUM>, and a portion of the third region <NUM> may be disposed in the second frame <NUM> while still being rolled on the roller <NUM>. In addition, for the smooth movement of the third region <NUM>, the second region <NUM> may also move in the first direction D1 with respect to the second frame <NUM> together with the third frame <NUM>. In addition, as described above, the second region <NUM> and the third frame <NUM> may be constrained to the second frame <NUM> and move in the first direction D1 with respect to the first frame <NUM> together with the second frame <NUM>. Accordingly, the second region <NUM> and the third frame <NUM> may move in the first direction D1 relative to the first frame <NUM> as well as the second frame <NUM>, and accordingly, move a distance longer than the moved distance of the second frame <NUM>. Thus, because of such long distance movement in the first direction D1 of the second region <NUM>, the third region <NUM> may be smoothly extended to the front face of the mobile terminal <NUM>. Further, for the movement of the third region <NUM>, which is proportional to the expansion of the second frame <NUM>, the movement of the second region <NUM> and the third frame <NUM> in the first direction D1 may be performed simultaneously with the movement of such third region <NUM> and second frame <NUM> in the first direction D1 so as to be proportional to the movement of third region <NUM> and second frame <NUM>.

When the second frame <NUM> is fully extended in the first direction D1, the first and third regions <NUM> and <NUM> may be arranged on the front face of the mobile terminal <NUM>, and only the second region <NUM> may be disposed on the rear face of the mobile terminal <NUM>. Such first and third regions <NUM> and <NUM> may be supported by the first frame (i.e., the first front portion <NUM> thereof) and the second frame (i.e., the second front portion <NUM> thereof). In addition, the second frame <NUM>, i.e., the third rear portion <NUM> thereof exposes the second rear portion <NUM> of the first frame while extending in the first direction D1, and supports the moving third region <NUM>. Therefore, in the second state, the mobile terminal <NUM> may have the extended front face display unit <NUM>.

On the other hand, when the second frame <NUM> moves in the second direction D2 in the second state, the mobile terminal <NUM> may again return into the first state as shown in <FIG>, <FIG>, and <FIG>. The second frame <NUM> may be contracted to the first frame <NUM> by the movement in the second direction D2, and may reduce the overall size of the mobile terminal <NUM>, particularly the front face thereof. The movement of the display unit <NUM> during such movement of the second frame <NUM> may be performed in a reverse order of the movement in the first direction D1 described above. In brief, the third region <NUM> may be rolled from the front face of the mobile terminal <NUM> into the roller <NUM> of the second frame <NUM>, or may be inserted, retracted, or moved into the second frame <NUM>. At the same time, the third region <NUM> may be rolled, withdrawn, extended, or moved out of the roller <NUM> of the second frame <NUM> to the rear face of the mobile terminal <NUM>. Not the entirety of the third region <NUM> may be withdrawn from the second frame <NUM> to the rear face of the mobile terminal <NUM>, and the portion of the third region <NUM> may still be placed in the second frame <NUM> while still being rolled on the roller <NUM>. In addition, for such smooth movement of the third region <NUM>, the second region <NUM> may also move in the second direction D2 with respect to the second frame <NUM> together with the third frame <NUM>. The second region <NUM> and the third frame <NUM> may be constrained to the second frame <NUM> to move in the second direction D2 with respect to the first frame <NUM> together with the second frame <NUM>. Accordingly, the second region <NUM> and the third frame <NUM> may move relatively in the second direction D2 with respect to not only the second frame <NUM> but also the first frame <NUM>. As a result, the second region <NUM> and the third frame <NUM> may move in the second direction D2 a distance larger than the moved distance of the second frame <NUM>. Thus, because of such long distance movement of the second region <NUM>, the third region <NUM> may be smoothly returned to the rear face of the mobile terminal <NUM>. Further, for the movement of the third region <NUM> proportional to the contraction of the second frame <NUM>, the movements of the second region <NUM> and the third frame <NUM> in the second direction D2 may be performed simultaneously with the movements of the third region <NUM> and the second frame <NUM> in the second direction D2 to be proportional to the movements of the third region <NUM> and the second frame <NUM>. When the second frame <NUM> is completely contracted in the second direction D2, the mobile terminal <NUM> may be converted into the first state as described above, and may have the display unit <NUM> with the front face that is relatively reduced in comparison with the second state in the first state.

The flexible display unit <NUM> containing the variable portion is applicable not only to the above-described embodiment in which a width in the first direction of the mobile terminal <NUM> is variable because of the sliding of the second frame <NUM>, but also to a mobile terminal in which an angle between the plurality of frames <NUM> and <NUM> may vary.

For example, the flexible display unit may be applied to a mobile terminal including a first frame and a second frame that is hinge coupled to one side of the first frame and an having a variable angle with the first frame. A variable portion of the mobile terminal of such form may mean a position where a bending angle changes when the angle between the first frame and the second frame changes, and may be located between the first frame and the second frame.

One face of the flexible display unit <NUM> may output the video thereon, and may be exposed to the outside. Because a bent position or a curvature of bending deflection varies in the variable portion, a support frame <NUM> in which a curvature thereof may vary corresponding thereto is required. The support frame <NUM> is a flexible member coupled to the other face of the variable portion of the flexible display unit. When the support frame <NUM> supports the other face of the flexible display unit <NUM>, stable touch input may be possible even in the variable portion, and the variable portion may be prevented from being damaged by the external force.

In addition, as described above, the second front portion <NUM> of the second frame is inside the first front portion <NUM> of the first frame in the first state, and then moves in the first direction in the second state, so that a gap corresponding to a thickness of the first front portion <NUM> occurs between the flexible display unit <NUM> and the second front portion <NUM>. Using the support frame <NUM> having a thickness corresponding to the gap, a problem in which the front portion extended in the second state is spaced apart from the second front portion <NUM> may be solved.

When the support frame <NUM> has sufficient rigidity, the second front portion may be omitted. Hereinafter, the support frame <NUM> supporting the variable portion of the flexible display unit will be described in detail.

In a case of the flexible mobile terminal <NUM>, which is the mobile terminal <NUM> of the type in which the sizes of the frames <NUM> and <NUM> are extended and reduced as shown in <FIG>, the above-described foldable type mobile terminal <NUM> may be configured such that the flexible display unit <NUM> is bent with curvature only in a specific direction without bending in all directions. In order to consider the structures of the frames <NUM> and <NUM> and to minimize a possibility of damage of the flexible display unit <NUM>, the flexible display unit <NUM> may be bent only in a specific direction (first direction). The support frame <NUM> may also be bent only in the first direction, and may have rigidity in the third direction perpendicular to the first direction. <FIG> illustrates a coupling state of the flexible display unit <NUM> and the support frame <NUM> of the present disclosure. One face of the support frame <NUM> may be positioned on the other face of the variable portion of the flexible display unit <NUM>, and may vary as the form of the variable portion varies.

The support frame <NUM> includes a plurality of rigid bars <NUM> short in the first direction and elongated in the third direction. The rigid bar <NUM> may use a metal member having rigidity such as SUS or STS. The rigid bar <NUM> extending in the third direction provides rigidity in the third direction and is short in the first direction, thereby minimizing an effect on the bending deflection in the first direction of the flexible display unit <NUM>. As shown in <FIG>, the plurality of rigid bars <NUM> may be arranged side by side in the first direction.

Since it is difficult to couple the plurality of rigid bars <NUM> to the rear face of the flexible display unit <NUM> one by one, a flexible portion <NUM> made of a flexible material may be connected between the plurality of rigid bars <NUM> in the present disclosure. The flexible portion <NUM> may contain the flexible material, such as silicon, and arrange the plurality of rigid bars <NUM> in parallel, and be coupled with the plurality of rigid bars <NUM> in a double injection molding scheme to form one support frame <NUM>.

<FIG> is a view for describing a position and an operation of the sensing unit <NUM> of the mobile terminal <NUM>. <FIG> is a front view of the mobile terminal <NUM>, which removes the display unit <NUM> and illustrates the first frame <NUM> and the second frame <NUM>. <FIG> shows the first state, and <FIG> shows the second state. In the conversion from the first state to the second state, an overlapped area of the first frame <NUM> and the second frame <NUM> is changed. In the first state, the overlapping area of the first frame <NUM> and the second frame <NUM> becomes maximum, and in the second state, the overlapping area of the first frame <NUM> and the second frame <NUM> becomes minimum.

The driving unit <NUM> may include a motor <NUM> positioned on the first frame <NUM> and a linear gear <NUM> that linearly moves in the first direction or the second direction when the motor <NUM> is driven. The linear gear <NUM> is coupled to the second frame <NUM> to change a rotational force of the motor <NUM> to a linear motion to change the position of the second frame <NUM>.

In order to assist the movement of the driving unit <NUM>, a slide rail <NUM> formed on the first frame <NUM> and a slidably-moving portion moving along the slide rail <NUM> and fixed to the second frame <NUM> may be included. The slidably-moving portion may have a rail shape extending in the first direction as shown in <FIG>. The slidably-moving portion extended in the first direction has a large area engaged with the slide rail <NUM>, so that the slidably-moving portion may move more stably while reducing a distortion because of the wide engaged area.

An embodiment shown in <FIG> has a form in which the slide move portion has a groove defined therein for inserting the slide rail <NUM> therein. On the contrary, a form in which a groove extending in the first direction may be defined in the slide rail <NUM>, and the slidably-moving portion moves along the groove is available.

However, when the second frame <NUM> reaches the first state and the second state and then does not stop the operation correctly, a load may be applied on the flexible display unit <NUM> or other components, so that the second frame <NUM> may be damaged. Further, although the motor <NUM> operates, the second frame <NUM> is no longer movable, so that noise may occur. To solve such problem, the controller <NUM> needs to control the driving unit <NUM> to stop exactly when the first state or the second state is reached. Further, a sensing unit <NUM> for detecting the state of the mobile terminal <NUM> may be further included.

A pair of driving units <NUM> may be arranged in the third direction (vertical direction in the drawing) as shown in <FIG>, so that the second frame <NUM> may move stably. When speeds of the pair of driving units <NUM> are different, the second frame <NUM> may be distorted. Thus, the pair of driving units <NUM> must be synchronized and move at the same speed.

However, when the pair of driving units <NUM> are different in speed or artificially restrict the movement of the second frame <NUM>, the second frame <NUM> may be tilted. In this case, the speed of the pair of driving units <NUM> must be adjusted to correct the tilted position of the second frame <NUM>. As such, in order for the controller <NUM> to control the driving unit <NUM> accurately, the sensing unit <NUM> capable of accurately detecting the position of the second frame <NUM> is required.

In addition, when the position of the second frame <NUM> may be accurately detected through the sensing unit <NUM>, the controller <NUM> may output a video having a size corresponding to an area of the portion of the flexible display unit <NUM> located on the front face.

In order to detect positions of two members, a magnet and a hall sensor that detects magnetism of the magnet may be used. For example, when a magnet located in the second frame <NUM> moves to be adjacent to a hall sensor located in the first frame <NUM>, the hall sensor may detect the movement of the second frame <NUM>, and thus, detect the position of the second frame <NUM>. However, since a hall sensor scheme uses a magnetic force, many electronic components in the mobile terminal <NUM> may be affected, and since magnets are already used in the speaker and the like in the mobile terminal <NUM>, an interference may occur. In addition, an accuracy of the position of the second frame <NUM> that may be detected by the hall sensor is low.

In order to solve the above problem, the slide rail <NUM> and the slidably-moving portion <NUM> described above may include resistors and electrodes, and thus may detect a position of the slidably-moving portion on the slide rail <NUM> based on the movement of the second frame <NUM>.

<FIG> is a diagram illustrating an embodiment of the sensing unit <NUM> of the mobile terminal <NUM>, and the sensing unit <NUM> is formed on the slide rail <NUM> and the slidably-moving portion <NUM>. The sensing unit <NUM> includes a sensing terminal <NUM> located on the slide rail <NUM>. The sensing unit <NUM> may include a sensing resistor <NUM> connected to the sensing terminal <NUM>, and an input resistor <NUM> positioned between the sensing terminal <NUM> and a power supply unit. The sensing unit <NUM> may include a ground terminal <NUM>, which may be in contact with the sensing terminal <NUM>, on a face of the slidably-moving portion <NUM> facing the slide rail <NUM>. The ground terminal <NUM> is a grounded electrode. When the sensing terminal <NUM> and the ground terminal <NUM> are in contact with each other, a circuit connected to the sensing terminal <NUM> is grounded. Further, when power is applied from the power supply unit, current flows to the input resistor <NUM>, the sensing resistor <NUM>, the sensing terminal <NUM>, and the ground terminal <NUM>.

When measuring a voltage (Vout) between the input resistor <NUM> and the sensing resistor <NUM>, the detecting unit may calculate a resistance value of the sensing resistor <NUM> through a formula shown in <FIG> using values of an input voltage Vin and a resistance of the input resistor <NUM>.

As illustrated in <FIG>, a plurality of sensing terminals <NUM> may be provided along the slide rail <NUM>, and in this case, the sensing resistors <NUM> of the respective sensing terminals <NUM> may be different. <FIG> is a view for describing the operating principle of the sensing unit <NUM>. As shown in <FIG>, depending on the position of the slidably-moving portion <NUM> on the slide rail <NUM>, a sensing terminal <NUM> in contact with the ground terminal <NUM> varies, and the resistance value of the sensing resistor <NUM> through which power applied from the power supply unit (Vin) passes. Accordingly, a resistance value of the output resistor detected by the detecting unit also varies. Based on the resistance value of the output resistor detected by the detecting unit, the controller may determine the position of the sensing terminal <NUM> in contact with the ground terminal <NUM>. Further, the controller may calculate the position of the second frame <NUM> on the first frame <NUM> based on the determined position of the sensing terminal <NUM>.

Since the area of the portion of the flexible display unit <NUM> located on the front face varies based on the position of the second frame <NUM>, the size of the video output on the flexible display unit <NUM> may be adjusted based on the position of the second frame <NUM>.

When the second frame <NUM> automatically moves using the driving unit, the second frame <NUM> may be controlled to stop at a position corresponding to the first state or the second state by adjusting the speed of the motor of the driving unit. The sensing terminal <NUM> may be added to control the second frame <NUM> to stop at an intermediate state between the first state and the second state.

<FIG> is a view illustrating cross-sections of the sensing unit <NUM> depending on positions of the sensing unit <NUM>. Only the sensing terminal <NUM> located in a portion A. The sensing terminal <NUM> may have a pogo pin shape. When being in contact with the ground terminal <NUM>, the pogo pin may be withdrawn into the slide rail <NUM>, as in a portion B.

As shown in <FIG>, the slidably-moving portion <NUM> may define a groove <NUM>' extending in the first direction in a face facing a face where the sensing terminal <NUM> is positioned, as shown in a portion C such that the slidably-moving portion <NUM> does not come into contact with the sensing terminal <NUM>. A height of the groove <NUM>' may be greater than a height of the pogo pin, and the ground terminal <NUM> may be disposed in the groove <NUM>'. The ground terminal <NUM> may use a conductive gasket containing an elastic material to be in close contact with the pogo pin.

<FIG> is a diagram illustrating another embodiment of the sensing unit <NUM> of the mobile terminal <NUM>. The member that slidably moves when the state of the mobile terminal <NUM> of the present disclosure is changed may slidably move the display unit in addition to the second frame <NUM> in the first direction. The flexible display unit <NUM> has the fixed portion fixed to the first frame <NUM> and the variable portion rolled in the second frame <NUM> and changed in size at the front face and the rear face. An end of the variable portion is coupled with the third frame <NUM> which slidably moves on the rear face of the second frame <NUM>, and moves on the rear face of the second frame <NUM>.

The sensing unit <NUM> may detect the state change based on the position change between the second frame <NUM> and the flexible display unit <NUM>. When the second frame <NUM> moves by d relative to the first frame <NUM>, the end of the variable portion or the third frame <NUM> moves by d with respect to the second frame <NUM>, and as a result, the same result as in the above-described embodiment may be obtained.

The slide rail <NUM> may be formed on the second frame <NUM>, and the slidably-moving portion that moves along the slide rail <NUM> of the second frame <NUM> may be positioned on the flexible display. Since the bending deflection occurs in the portion of the variable portion moving between the front face and the rear face, and thus, it is hard to implement the slidably-moving portion, the slidably-moving portion of the present embodiment may be positioned at the end of the variable portion of the flexible display unit <NUM>. The third frame <NUM> located at the end of the variable portion may include the slidably-moving portion.

The flexible display unit <NUM> may include a curved display panel <NUM> for outputting the video and a back plate <NUM> for supporting a rear face of the display panel <NUM>. As the curved display panel <NUM>, an OLED panel or a panel using micro LEDs may be used, and the back plate <NUM> may be a thin plate member of a metal member supporting a weak display panel. Since the back plate <NUM> has a large area, the back plate <NUM> may serve as a ground. The back plate <NUM> of the flexible display unit <NUM> may be used to ground the ground terminal located in the slidably-moving portion.

<FIG> illustrates only portions of the flexible display unit <NUM> because it is difficult to illustrate an entirety of the flexible display unit <NUM>.

As shown in <FIG>, the sensing terminal <NUM> and the ground terminal <NUM> may be arranged on a face where the slide rail <NUM> and the flexible display unit <NUM> face each other. However, as shown in <FIG>, the sensing terminal <NUM> may be disposed on a side face of the slide rail1029, and the ground terminal <NUM> extending from the rear face of the flexible display unit <NUM> may be provided.

The sensing resistor <NUM> and the input resistor <NUM> may be implemented using the flexible substrate <NUM>, and the sensing terminal <NUM> connected to the sensing resistor <NUM> may be mounted on a surface of the flexible substrate <NUM>. The sensing terminal <NUM> may be in the form of the pogo pin as described above, or may be in a form of an electrode of a conductive material exposed on the surface of the general flexible display unit <NUM>.

As described above, the applying of the load on the terminal may be prevented by stopping the driving unit <NUM> at a time when the state conversion of the mobile terminal <NUM> is completed using an optical detection sensor <NUM> and markers <NUM>, <NUM>, and <NUM>. In addition, the plurality of driving units <NUM> may be synchronized with each other and move the second frame <NUM> at a uniform speed, thereby reducing defects occurring during the state conversion.

The mobile terminal that detects the moved distance of the frame and controls the driving unit to move the frame stably without the distortion may be provided. In addition, since the size of the video output on the display unit may be accurately adjusted, usability may be improved.

Claim 1:
A mobile terminal (<NUM>) comprising:
a first frame (<NUM>);
a second frame (<NUM>) slidable with respect to the first frame (<NUM>) in a first direction (D1) and in a second direction (D2) opposite to the first direction (D1);
a slide rail (<NUM>) formed on the first frame (<NUM>) and extending in the first direction (D1);
a slidably-moving portion (<NUM>) fixed to the second frame (<NUM>) and movable along the slide rail (<NUM>) in the first direction (D1) and in the second direction (D2);
a sensing terminal (<NUM>) located on the slide rail (<NUM>);
a ground terminal (<NUM>) located on a face of the slidably-moving portion (<NUM>) facing the slide rail (<NUM>) and configured to contact the sensing terminal (<NUM>) at predetermined first position of the slidably-moving portion (<NUM>) with respect to the slide rail (<NUM>) corresponding to a predetermined first sliding position of the second frame (<NUM>) with respect to the first frame (<NUM>);
a power supply unit (<NUM>);
an input resistor (<NUM>) having one end connected to the power supply unit (<NUM>);
a sensing resistor (<NUM>) having one end connected to the sensing terminal (<NUM>) and the other end connected to the other end of the input resistor (<NUM>);
a detecting unit configured to measure the voltage (Vout) at said other end of the input resistor (<NUM>); and
a controller (<NUM>) configured to determine the sliding position of the second frame (<NUM>) with respect to the first frame (<NUM>) when the ground terminal (<NUM>) is in contact with the sensing terminal (<NUM>) based on the voltage measured by the detecting unit.