Abstract:
A wearable display device that employs a sliding structure is disclosed. The device includes: a frame; a main unit coupled to the frame; a display unit coupled to the main unit and configured to show an image on at least a portion thereof; and a sliding element for sliding the display unit from the main unit, where the display unit comprises a hinge for bending a part of the display unit. With the device disclosed herein, it is possible to prevent malfunctioning and damage even when the device is worn for extended periods, and it is also possible to resolve the problem of the wearable display device obstructing the field of vision when not in use.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of Korean Patent Application Nos. 10-2012-0086484 (filed on Aug. 7, 2012), 10-2012-0092937 (filed on Aug. 24, 2012), 10-2013-0027645 (filed on Mar. 15, 2013), and 10-2013-0038272 (filed on Apr. 8, 2013) filed with the Korean Intellectual Property Office. The disclosures of the above applications are incorporated herein by reference in their entirety. 
       BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present invention relates to a wearable display device. 
         [0004]    2. Description of the Related Art 
         [0005]    The HMD (head-mounted display), a representative type of wearable display device, was designed to provide a pilot with aviation information such as the altitude, velocity, etc., of the aircraft. Commercial products were first developed during the 1990&#39;s, and have attracted interest after 1997 due to their popularity. The HMD may be worn on the head like goggles and may provide the vision of a large screen showing virtual images. The display used here typically has a size of 1 inch or less, which may be magnified a hundredfold with the application of highly advanced optical technology. 
         [0006]    With the development and commercialization of accessory devices such as the HMD, further growth is anticipated in the field of wearable computing devices. While previous efforts have focused on developing the HMD for movies or games, rapid advances in the fields of display devices and visual communication, as exemplified by the trends towards higher performance and smaller sizes in computer systems and LCD&#39;s, have led to research on wearable monitors, with some products already commercially available. 
         [0007]    The HMD market faced many difficulties in the market for the past few years, due to relatively high prices, but the market is expected to grow dramatically in step with the trends in the wearable computer industry. The wearable HMD is expected to expand to industrial sites, logistics warehouses, maintenance sites for large-scale equipment such as cars, airplanes, and ships, etc., as well as to the field of sports entertainment, such as car racing. 
         [0008]    In particular, developments in processor and software technology enable the miniaturization of computing devices, and as such, the HMD is expected to evolve beyond simply displaying images to becoming a personal computing device analogous to the smart phone. 
         [0009]      FIG. 1  illustrates an example of a wearable display device that can operate as a computing device. 
         [0010]    Referring to  FIG. 1 , a wearable display device according to the related art can include an image viewer unit  100 , a connection unit  102 , a main unit  120  that includes an interface unit  104  and a processor unit  106 , and a frame  110 . 
         [0011]    The frame  110  may form the main body of the wearable display device and, for example, can have a structure similar to a pair of glasses, as illustrated in  FIG. 1 . The frame can be structured to be wearable on the user&#39;s head, and the other components of the wearable display device may be coupled onto the frame  110 . 
         [0012]    The image viewer unit  100  may serve to show images and may be positioned in front of the user&#39;s eye. 
         [0013]    The main unit  120 , composed of the interface unit  104  and the processor unit  106 , may be coupled to the frame  110 , for example on a support part  110   c  of the frame  110  for wearing on the user&#39;s ear. 
         [0014]    The interface unit  104  may provide an interface with which the user can input a control command. The interface unit  104  can include a number of buttons and can include a flat touch pad for inputting cursor movements. By using the interface unit  104 , the user can input a necessary control command, such as for playing a video clip and searching information, for example. 
         [0015]    The processor unit  106  may control the operations of the wearable display device for use as a computing device. The user&#39;s control commands inputted through the interface unit  104  may be provided to the processor unit  106 , after which the processor unit  106  may then process the user&#39;s control commands. 
         [0016]    In a wearable display device according to the related art, such as that illustrated in  FIG. 1 , the image viewer unit  100  may be installed in front of the user&#39;s eyes and may thus obstruct the user&#39;s field of vision when it is not in use. 
         [0017]    Also, in the wearable display device according to the related art, the interface unit  104  may be fixed to the frame and exposed to the exterior, forming a structure that is vulnerable to damage caused by dust and moisture, etc. 
         [0018]    Thus, the wearable display device according to the related art, when worn for extended periods, can cause considerable discomfort due to the obstruction of vision and can be more susceptible to damage. 
       SUMMARY 
       [0019]    An aspect of the invention is to propose a wearable display device of which malfunctioning and damage can be prevented even when the device is worn for extended periods. 
         [0020]    Also, an aspect of the invention is to propose a wearable display device that does not obstruct the user&#39;s field of vision when not in use. 
         [0021]    One aspect of the invention provides a wearable display device that includes: a frame; a main unit coupled to the frame; a display unit coupled to the main unit and configured to show an image on at least a portion thereof; and a sliding element for sliding the display unit from the main unit, where the display unit comprises a hinge for bending a part of the display unit. 
         [0022]    The display unit may be disposed to hide an interface formed on the main unit, in a first mode, and may be slid from the main unit to have a part bent, in a second mode. 
         [0023]    The sliding of the display unit in the second mode may cause the interface of the main unit to be exposed. 
         [0024]    The display unit may include a bending part that is bent by the hinge and a non-bending part that is not bent, and an exposed surface of the non-bending part exposed by the bending of the bending part may have a camera coupled thereto. 
         [0025]    The bending part may have a display disposed thereon for showing images, and the display may be positioned in front of a user&#39;s eye in the second mode. 
         [0026]    The sliding element may include a guide hole formed in the main unit and a guide protrusion formed on the display part. 
         [0027]    The wearable display device may further include a bend control part for automatically bending the bending part of the display unit. 
         [0028]    The wearable display device may further include a detector part configured to detect a danger state of a user, where the bend control part may bend the bending part of the display unit if the detector part detects a danger state of the user. 
         [0029]    The bend control part may automatically bend the bending part of the display unit if power is turned off or if a usage time exceeds a preset threshold time. 
         [0030]    Another aspect of the invention provides a wearable display device that includes: a frame; a main unit, which is coupled to the frame, and on which an interface is formed; a display unit coupled to the main unit and configured to show an image on at least a portion thereof; and a sliding element for sliding the display unit from the main unit, where the sliding of the display unit causes the interface of the main unit to be exposed. 
         [0031]    Yet another aspect of the invention provides a wearable display device that includes: a frame; a main unit coupled to the frame; a non-bending part coupled to the main unit and configured for a sliding movement; a hinge coupled with the non-bending part; and a bending part, which is configured to provide a user with image information and coupled with the hinge to rotate within a preset angle. 
         [0032]    An aspect of the invention makes it possible to prevent malfunctioning and damage, even when the device is worn for extended periods. 
         [0033]    Also, an aspect of the invention can resolve the problem of the wearable display device obstructing the field of vision when not in use. 
         [0034]    Additional aspects and advantages of the present invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0035]      FIG. 1  illustrates an example of a wearable display device that can operate as a computing device. 
           [0036]      FIG. 2  illustrates the structure in a first mode of a wearable display device according to an embodiment of the invention. 
           [0037]      FIG. 3  illustrates the structure in a second mode of a wearable display device according to an embodiment of the invention. 
           [0038]      FIG. 4  illustrates a wearable display device according to an embodiment of the invention before the display unit is bent. 
           [0039]      FIG. 5  is a perspective view of the main unit  220  and the display unit  200  of a wearable display device according to an embodiment of the invention in the first mode. 
           [0040]      FIG. 6  is a cross-sectional view of the wearable display device illustrated in  FIG. 5 . 
           [0041]      FIG. 7  is a perspective view of the display unit of a wearable display device according to an embodiment of the invention, with the display unit shown after sliding. 
           [0042]      FIG. 8A  and  FIG. 8B  are perspective views of the display unit of a wearable display device according to an embodiment of the invention in the second mode. 
           [0043]      FIG. 9  is a block diagram illustrating the modules of a wearable display device according to an embodiment of the invention. 
           [0044]      FIG. 10  is a block diagram illustrating the modules of a wearable display device according to another embodiment of the invention. 
           [0045]      FIG. 11  is a block diagram illustrating the modular composition of a detector part according to an embodiment of the invention. 
           [0046]      FIG. 12  is a block diagram illustrating the modular composition of a dangerous object detector part according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0047]    As the present invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to particular modes of practice, and it is to be appreciated that all changes, equivalents, and substitutes that do not depart from the spirit and technical scope of the present invention are encompassed in the present invention. In describing the drawings, like reference numerals are used for like elements. 
         [0048]      FIG. 2  illustrates the structure in a first mode of a wearable display device according to an embodiment of the invention,  FIG. 3  illustrates the structure in a second mode of a wearable display device according to an embodiment of the invention, and  FIG. 4  illustrates a wearable display device according to an embodiment of the invention before the display unit is bent. 
         [0049]    In  FIGS. 2 to 4 , the first mode refers to a mode in which the image viewer function of the wearable display device is not used, while the second mode refers to a mode in which the image viewer function of the wearable display device is used. 
         [0050]    Referring to  FIGS. 2 to 4 , a wearable display device according to an embodiment of the invention can include a display unit  200 , a main unit  220 , a hinge  202 , and a frame  210 . 
         [0051]    The frame  210 , to which the wearable display device may be coupled, can have a structure similar to that of a pair of glasses, for example, as illustrated in  FIGS. 2 to 4 . The frame may be structured to be wearable on a user&#39;s head, and other components of the wearable display device may be coupled onto the frame  210 . 
         [0052]    The frame  210  can be made from various materials including metals and dielectrics, but using a dielectric material can be considered so as not to influence computing operations and RF signal reception. 
         [0053]    While  FIG. 2  illustrates an example in which the frame is of a similar form to that of a pair of glasses, the frame  210  can take any form that is wearable on the user&#39;s body. For instance, the frame can take the form of a helmet or a set of headphones. 
         [0054]    In cases where the frame has a form similar to a pair of glasses, an example of which is illustrated in  FIG. 2 , the frame may include two lens-mounting parts  210   a ,  210   b . A user who needs prescription glasses can mount lenses onto the lens-mounting parts  210   a ,  210   b  for use. 
         [0055]    Also, the frame  210  may include two support parts  210   c ,  210   d  for wearing the frame on the user&#39;s ears. 
         [0056]    The main unit  220  can be equipped with a processor for controlling the wearable display device, and an interface can be provided by way of the main unit. 
         [0057]    The main unit  220  may be coupled to the frame  210  and may be coupled, for example, on a support part  210   c  of the frame  210  intended for wearing on the user&#39;s ear. 
         [0058]    The interface provided by the main unit  220  may serve to receive control information from the user and provide it to the processor. The interface may receive control information for turning the power on or off, as well as various control information related to the operation of the wearable display device, from the user. For example, various control commands such as for playing a video clip, making a voice call, searching information, etc., can be provided through the interface. 
         [0059]    The interface can be implemented in various forms. For example, it is possible to provide control information through a number of buttons, and it is also possible to provide a flat touch pad such as that for a mouse controller on a laptop. 
         [0060]    While the image viewer function is not being used (i.e. in the first mode), the main unit  220  and the display unit  200  may be coupled parallel to each other, as illustrated in  FIG. 2 . Since the main unit  220  and the display unit  200  are structured to overlap each other during this non-use state, the display unit  200  may operate as a cover that shields the interface formed on the main unit  220 . 
         [0061]    The display unit  200  may be slidably coupled with the main unit  220 , and when the display unit is to be used, the display unit  200  may be slid preliminarily from the main unit  220 , as illustrated in  FIG. 4 . The display unit  200  can be moved in a direction in which the area of overlap with the main unit  220  increases and its opposite direction, the direction in which the area of overlap with the main unit  220  decreases. 
         [0062]    The sliding action which changes the arrangement in  FIG. 2  to the arrangement in  FIG. 4  can be applied manually, or a structure for automatically performing the sliding can also be used. 
         [0063]    After the display unit  200  is preliminarily slid as in  FIG. 4 , the display unit  200  may be bent by way of a hinge  202  formed at a particular point, as illustrated in  FIG. 3 . The display unit  200  may be divided into the bending part  200   a  and the non-bending part  200   b , each formed on either side of the hinge  202 , where the bending part  200   a  can be bent within a preset angle after the sliding. In a wearable display device such as that illustrated in  FIGS. 2 to 4 , the bending part  200   a  can be bent by an angle of about 90 degrees. 
         [0064]    Of course, unlike the structure illustrated in  FIGS. 2 to 4 , the sliding and the bending actions can be implemented simultaneously. For example, as the sliding is being performed, the bending angle of the bending part can be gradually increased, such that the final result is as shown in  FIG. 3 . 
         [0065]    A display  200   c  which shows images on the display unit  200  may be formed on the bending part  200   a , and by way of the bending action of about 90 degrees, the display may be positioned in front of the user&#39;s eye in the second mode. 
         [0066]    In order to exchange information with one another, the main unit  220 , bending part  200   a , and non-bending part  200   b  can be connected by cables capable of transmitting electrical signals. Alternatively, the main unit  220 , bending part  200   a , and non-bending part  200   b  can exchange information wirelessly. Here, the exchanged information can include control information inputted through the interface formed on the main unit. 
         [0067]    The display  200   c  formed on the display unit  200  may serve to show images and may provide the user with image information. The display  200   c  can have a size of about 1 inch in the form of a micro-display and can show images using various known methods. It may be preferable to have the display  200   c  be made of a transparent material, but the invention is not thus limited. 
         [0068]    In order to show an image on the display  200   c , an external light source can be used, or a self-illuminating system can be used. 
         [0069]    An example of using a self-illuminating system is to use OLED&#39;s. An OLED contains electrons and holes, which undergo an excitation state and then recombine to produce light. As it can emit light by itself, it is possible to show images without a separate external light source. 
         [0070]    An example of using a system with an external light source is to use a transparent display. One such example is the TFT-LCD, which is structured such that light emitted from a fluorescent lamp is directed towards a liquid crystal panel by a device that reflects and disperses the light. The liquid crystal panel includes twisted nematic (TN) liquid crystals filled in between two glass sheets; the glass sheet on the side where light enters includes TFT and ITO pixels and a liquid crystal alignment layer, while the glass sheet on the other side is structured with a color filter and a coated liquid crystal alignment layer (polyimide). 
         [0071]    Another example of using a system with an external light source is to use a reflective display. One example of a reflective display is the LCos, in which light is reflected with a reflective display to show images. A silicon substrate is mainly used for the display element, and it is possible to show images of a high resolution on a small display screen. 
         [0072]    Although it is not illustrated in  FIGS. 2 to 4 , a protector part (not shown) for protecting the display unit  200  in the first mode can be additionally included. At least one surface of the protector part may be open, to enable the sliding of the display unit  200 . For instance, the protector part can be structured to surround the display unit  200 . 
         [0073]    In the first mode, the display unit  200  may be positioned within the protector part, but in the second mode, it may move from the inside to the outside of the protector part. 
         [0074]      FIG. 5  is a perspective view of the main unit  220  and the display unit  200  of a wearable display device according to an embodiment of the invention in the first mode,  FIG. 6  is a cross-sectional view of the wearable display device illustrated in  FIG. 5  across line A-A′, and  FIG. 7  is a perspective view of the display unit of a wearable display device according to an embodiment of the invention, with the display unit shown after sliding.  FIG. 8A  and  FIG. 8B  are perspective views of the display unit of a wearable display device according to an embodiment of the invention in the second mode.  FIG. 8A  and  FIG. 8B  are perspective views each illustrating the display unit from different directions. 
         [0075]    Referring to  FIG. 5  and  FIG. 6 , in the first mode (display unit not in use), the main unit  220  and the display unit  200  may be coupled parallel to each other, and the interface of the main unit  220  may not be exposed in the first mode. While  FIGS. 5 and 6  illustrate an embodiment in which the main unit  220  and the display unit  200  have substantially the same sizes, this is merely one example, and it is obvious to those skilled in the art that the sizes can be different. 
         [0076]    The hinge  202  may be formed on the display unit  200 , so that the structure of the display unit  200  is bendable. 
         [0077]    Referring to the cross-sectional view in  FIG. 6  and the perspective views in  FIGS. 7 ,  8 A, and  8 B, a guide hole  600  may be formed in the main unit  220 , while a guide protrusion  610  corresponding to the guide hole  600  may be formed on the display unit  200 . 
         [0078]    The guide protrusion  610  may be inserted into the guide hole  600 , and the end of the guide protrusion  610  may be larger than the guide hole  600  so that the display unit  200  does not become detached from the main unit  220 . 
         [0079]    By way of the guide protrusion  610  and guide hole  600  illustrated in  FIGS. 6 and 7 , the display unit  200  is able to slide from the main unit, with the range of sliding determined by the length of the guide hole  600 . 
         [0080]    Although it is not illustrated in  FIGS. 6 and 7 , an elastic structure can be additionally included, which fixes the position of the display unit  200  to either the arrangement shown in  FIG. 2  or the arrangement shown in  FIG. 4 . In other words, a separate structure can be employed which may secure the guide protrusion  610  of the display unit  200  at one end or the other end of the guide hole  600 . 
         [0081]    According to another embodiment of the invention, the main unit  220  may not provide a processor and an interface, serving only as a base for the sliding, i.e. movement, of the display unit  200 . Here, an additional main unit (not shown) that does include a processor and an interface can be coupled to a support part  210   d  opposite the support part  210   c  on which the main unit  220  is coupled. In this case, the additional main unit and the display unit  200  can exchange information wirelessly. 
         [0082]    Referring to  FIGS. 8A and 8B , a camera  700  may be coupled to the exposed surface  200   d  of the non-bending part  200   b  that is exposed when the bending part  200   a  of the display unit  200  is bent. The camera  700  may serve to acquire image information in the forward direction. Also, the camera can be activated according to the position of the non-bending part  200   b . The camera can be activated when the non-bending part  200   b  moves in a first direction to be positioned in a preset region. For example, the camera can be activated when the non-bending part  200   b  is moved from the position in  FIG. 2  to the position in  FIG. 3 . 
         [0083]    Since the camera of the wearable display device can acquire image information in the forward direction at any time the wearable display device is worn, there is a concern that it may violate other people&#39;s privacy. Because of this, the wearable display device is often prohibited in certain places. In an embodiment of the invention, the camera may be coupled to the exposed surface  200   d  of the non-bending part that is exposed when the display unit  200  is in a bent state, so that the camera is only exposed during use. 
         [0084]    Also, when the display unit  200  is slid from the main unit  220  to allow the use of the display unit  200 , the interface  750  of the main unit  220  that was hidden by the display unit  200  may be exposed. 
         [0085]    According to an embodiment of the invention, the sliding and bending actions of the display unit  200  can be implemented manually. 
         [0086]    According to another embodiment of the invention, the sliding and bending actions of the display unit  200  can be implemented automatically by using a motor or an actuator, etc. On a particular point on the main unit  220 , an interface button may be included for controlling the automatic sliding and bending actions. Of course, it is also possible to have just one of the sliding action and the bending action be automatically implemented by a motor or an actuator. 
         [0087]    During use of the image viewer function (in second mode), when a preset condition is detected, the display unit  200  can be bent automatically. For example, if a danger condition is detected, the display unit  200  may be bent automatically to be removed from the user&#39;s field of vision. Here, the sliding action for converting to the first mode can also be implemented automatically. 
         [0088]    The images acquired by the camera  700  can be analyzed for the detection of danger conditions. The processor of the wearable display device may analyze the image information acquired from the camera to determine whether or not a dangerous object such as an automobile is approaching the user, and if it is determined that there is a danger condition, may provide the control for an automatic rotation action that removes the display unit from the user&#39;s field of vision. 
         [0089]    If there is no device included for automatically bending the display unit  200 , it is also possible to have the processor output alarm information, prompting the user to bend the display unit  200 . 
         [0090]    According to another embodiment of the invention, a type of sensor unit (not shown) other than the camera  700  can be additionally included, where the sensor unit may acquire additional information for determining whether or not the user faces a dangerous condition. 
         [0091]    For example, the sensor unit can detect information such as illuminance, temperature, etc., to provide information based on which to determine whether the user is located indoors or outdoors. If the user is located indoors, the processor can deactivate the function for detecting whether or not a dangerous object is approaching and the function for outputting alarm information, in order to reduce battery consumption. 
         [0092]    Also, the sensor unit can detect the movement speed of the user, which can be utilized as supplementary information in determining whether or not to activate the function for detecting the approach of dangerous objects. 
         [0093]    According to another embodiment of the invention, the processor can rotate the display unit  200  also in cases where the movement speed of the user exceeds a preset threshold. 
         [0094]    According to yet another embodiment of the invention, the display unit  200  can be bent automatically when the power is turned off for the wearable display device or when an allowed usage time is exceeded. 
         [0095]    A wearable display device based on an embodiment of the invention may preferably operate in a power-save mode during the first mode. When the display unit  200  is in contact with the main unit, it may be preferable to change the mode such that the image viewer function and audio output function are deactivated and only the function for outputting a preset alarm sound is activated. 
         [0096]      FIG. 9  is a block diagram illustrating the modules of a wearable display device according to an embodiment of the invention. 
         [0097]    Referring to  FIG. 9 , a wearable display device according to an embodiment of the invention can include a mode setter part  900 , a processor  902 , an interface receiver part  904 , a video driver  906 , and an audio driver  908 . 
         [0098]    The mode setter part  900  may serve to check the state of the display unit  200 , i.e. whether the display unit is coupled with the main unit as in  FIG. 2  or is rotated for use of the image viewer function, and may serve to set the settings to an operating mode corresponding to the checked state. If the display unit  200  is rotated and positioned in front of the user&#39;s eye, the wearable display device according to an embodiment of the invention may operate in a mode in which all functions are active. 
         [0099]    When the display unit  200  is in the first mode, with the display unit  200  not rotated, the wearable display device according to an embodiment of the invention may operate in a mode in which only some of the functions are active. 
         [0100]    The interface receiver part  904  may serve to receive from the user a control command for an interface and forward the user&#39;s control command to the processor  902 . 
         [0101]    The video driver  906  may serve to generate image signals that are to be shown on the image viewer unit  220 . When the display unit  200  is in a retracted state, the functions of the video driver  906  may be deactivated. 
         [0102]    The audio driver  908  may serve to generate audio signals that are to be provided to the user. 
         [0103]    The processor  902  may control the overall operations of the wearable display device and may process any control commands when they are received from the user. 
         [0104]      FIG. 10  is a block diagram illustrating the modules of a wearable display device according to another embodiment of the invention. 
         [0105]    Referring to  FIG. 10 , a wearable display device according to another embodiment of the invention may include a detector part  1000 , a bend control part  1002 , a mode setter part  1004 , a controller part  1006 , an interface receiver part  1008 , a setting part  1010 , a video driver  1012 , and an audio driver  1014 . 
         [0106]    The modules of the wearable display device illustrated in  FIG. 10  may be for an embodiment in which the bending of the display unit  200  is achieved automatically by the use of a motor or an actuator. 
         [0107]    The bend control part  1002  may control the bending operation of the display unit  200 . The display unit  200  may be bent if the user requests the bending of the display unit  200  through the interface or if a condition is detected that is associated with a setting for bending the display unit  200 . 
         [0108]    The detector part  1000  may determine whether or not a condition occurs that is associated with a setting for bending the display unit. The detector part  1000  may determine whether or not a condition has occurred that is associated with a setting for bending the display unit by analyzing the information acquired by the camera  700  or an additional sensor unit. 
         [0109]      FIG. 11  is a block diagram illustrating the modular composition of a detector part according to an embodiment of the invention. 
         [0110]    Referring to  FIG. 11 , a detector part  1000  according to an embodiment of the invention may include a dangerous object detector part  1100 , an environment detector part  1102 , and a motion detector part  1104 . 
         [0111]    The dangerous object detector part  1100  may analyze the information acquired from the camera or the sensor unit to determine whether or not a dangerous object approaches the user. For instance, the dangerous object detector part  1100  can determine whether or not a dangerous object approaches the user by analyzing image information provided from the camera. 
         [0112]    According to an embodiment of the invention, the dangerous object detector part  1100  may determine whether or not a dangerous object approaches the user by using at least one of an object feature, an object velocity, and an object direction or a combination thereof. 
         [0113]      FIG. 12  is a block diagram illustrating the modular composition of a dangerous object detector part according to an embodiment of the invention. 
         [0114]    Referring to  FIG. 12 , a dangerous object detector part  1100  according to an embodiment of the invention can include an object feature analyzer part  1200 , an object velocity analyzer part  1202 , an object direction analyzer part  1204 , and a determiner part  1206 . 
         [0115]    The object feature analyzer part  1200  may analyze the images obtained at the camera to determine whether or not an object exists that corresponds to a dangerous object. The information on the features of a dangerous object can be learnt beforehand, and the object feature analyzer part  1200  may determine whether or not an object corresponding to a dangerous object feature learnt beforehand exists in the acquired images. Here, an object feature can include an object&#39;s shape information, color information, and the like. 
         [0116]    The object feature analyzer part  1200  can determine whether or not a dangerous object exists in the acquired images by comparing the features of objects existing in the acquired images with the features of objects learnt beforehand. The comparing of object features is well known in the art and thus will not be elaborated here. 
         [0117]    The object velocity analyzer part  1202  may serve to analyze the movement speed of a dangerous object, if it is determined that a dangerous object is present. Image information can be used for the velocity analysis can utilize, while a separate radar or ultrasonic sensor, etc., can also be used. 
         [0118]    The object direction analyzer part  1204  may serve to analyze the movement direction of a moving object. The analysis of an object&#39;s direction can be performed by using the image information. 
         [0119]    The determiner part  1206  may use the information analyzed by the object feature analyzer part  1200 , object velocity analyzer part  1202 , and object direction analyzer part  1204  to determine whether or not the user faces a dangerous condition. 
         [0120]    It is obvious to the skilled person that the determiner part  1206  can not only determine whether or not the user faces a dangerous condition by considering all of the feature, velocity, and direction of an object, but also can be set to detect a danger simply if a dangerous object exists in front, irrespective of the velocity or direction of the object. In such cases, the dangerous object detector part can detect a danger by analyzing only the object features. 
         [0121]    Also, even when a particular object is determined not to correspond to a dangerous object set beforehand, if it is determined at the object velocity analyzer part  1202  that the object is approaching the user with a velocity greater than or equal to a threshold velocity, the determiner part can determine that the user faces a dangerous condition. 
         [0122]    The environment detector part  1102  may serve to detect whether the environment in which the user is located is outdoors or indoors. According to an embodiment of the invention, the issue of whether or not the user is indoors can be detected by using at least one of illuminance, light wavelengths, and temperature or a combination thereof. 
         [0123]    The environment detector part  1102  can also determine whether or not the user is indoors by using radio signals. For example, if the user is indoors so that the reception rate of a GPS signal is equal to or lower than a threshold value, the environment detector part  1102  can determine that the user is located indoors. Also, the environment detector part  1102  can determine that the user is indoors by identifying certain RFID or NFC modules installed indoors. 
         [0124]    The motion detector part  1104  may determine the movement speed of the user by using acceleration information detected from the sensor unit. The motion detector part  1104  may determine that the user faces a dangerous condition when the movement speed of the user is greater than or equal to a preset threshold value. 
         [0125]    The setting part  1010  may serve to configure the activation/deactivation settings for the function of detecting and outputting danger information. As the function for detecting and outputting danger information may require a considerable amount of power, the setting part  1010  may deactivate this function of detecting and outputting danger information under certain circumstances, in order to increase the battery use efficiency. 
         [0126]    According to an embodiment of the invention, the setting part  1010  may deactivate certain functions in response to the user&#39;s control command. For instance, the user may be provided with an interface for activating/deactivating the dangerous object detection function according to an embodiment of the invention, and if a control command for deactivating the detector function is selected by way of the interface, the setting part  1010  may deactivate the detector function. 
         [0127]    According to another embodiment of the invention, the setting part  1010  can deactivate certain functions by using the detection information of the detector part  1000 . For example, the setting part  1010  can deactivate the dangerous object detection function if the detector part  1000  determines that the user is located indoors. In another example, the setting part  1010  can deactivate the dangerous object detection function if the detector part  1000  determines that the user&#39;s movement speed is equal to or lower than a preset threshold speed. 
         [0128]    While the present invention has been described above using particular examples, including specific elements, by way of limited embodiments and drawings, it is to be appreciated that these are provided merely to aid the overall understanding of the present invention, the present invention is not to be limited to the embodiments above, and various modifications and alterations can be made from the disclosures above by a person having ordinary skill in the technical field to which the present invention pertains. Therefore, the spirit of the present invention must not be limited to the embodiments described herein, and the scope of the present invention must be regarded as encompassing not only the claims set forth below, but also their equivalents and variations.