Patent Publication Number: US-2020284905-A1

Title: Distance measurement device and control method therefor

Description:
TECHNICAL FIELD 
     The present disclosure relates to a distance measuring apparatus and a method for controlling the same. 
     BACKGROUND ART 
     Golf is a sport in which a golfer hits a golf ball into a hole. A golfer determines a target point in consideration of a current location of a golf ball and a location of a hole, and selects an appropriate golf club and hits the golf ball so that the golf ball moves to the target point. 
     In order to determine a location of a hole and a distance from a current location to the hole, a golfer refers to a flag (pin) affixed in a hole and a distance indication fixed facility installed along a fairway. However, the location of the hole is frequently changed, so that the fixed facility cannot reflect the momentarily changed location of the hole. Accordingly, it is difficult for the golfer to accurately grasp the distance from the current location to the hole. 
     Recently, a distance measuring apparatus using a distance measuring sensor has been released in order to more accurately measure a distance in a field. The distance measuring sensor measures the distance to the hole by emitting light, sound waves, etc. toward the target and receiving light, sound waves, etc. reflected from the pin. 
     However, even when using such a distance measurement sensor, the golfer has a problem in that it is difficult to fire light and sound waves by aiming at the pin accurately. In addition, when the golfer aims at an object other than the pin (e.g., a tree, a structure, etc.), the distance measuring apparatus has a problem of guiding the distance to the object rather than the pin to the golfer. 
     DISCLOSURE 
     Technical Problem 
     An object of the present disclosure is to solve the aforementioned problems and other problems. Another object is to provide a distance measuring apparatus for guiding a location of a hole in a field and a control method thereof. 
     Another object is to provide a distance measuring apparatus for guiding a distance to a hole in a field and a control method thereof. 
     Technical Solution 
     The present invention has been made in an effort to provide a distance measuring apparatus including: an output unit configured to output information; a memory configured to store map information of golf courses; a location acquiring sensor configured to acquire a current location; a distance measuring sensor configured to measure a distance to a target; a slope sensor configured to measure a tilt angle; and a control unit configured to read map information of the golf course corresponding to the current location from the memory, to calculate a first distance from the current location to a first point on the golf course by using the map information, to calculate a horizontal distance to the target by using the distance to the target and the tilt angle, and to output the horizontal distance to the output unit when the horizontal distance is within the first distance. 
     The distance measuring apparatus may further include an azimuth sensor configured to measure an azimuth, and the control unit may output the horizontal distance when the azimuth is included in a range between a first azimuth in a direction connecting a second point of the golf course from the current location and a second azimuth in a direction of connecting a third point of the golf course from the current location. 
     The second point and the third point may be two points where an arc and two radii of a fan having the first distance as a length of a radius thereof meet each other when a length of the arc of the fan satisfies a predetermined length. 
     A central angle of the fan is bisected by a connection line between the current location and the first point. 
     The second point and the third point may be two points where two tangent lines from the current location to the green of the golf course contact the green. 
     The first point may be a longest point from the current location on the green of the golf course. 
     The control unit may further calculate a second distance from the current location to a fourth point of the golf course, and may output the horizontal distance to the output unit when the horizontal distance is included in a range between the first distance and the second distance, and the fourth point may be a shortest point from the current location on the green of the golf course. 
     The second point and the third point may be two points that are in contact with a circle centered on the central point of the green of the golf course from the current position and having a predetermined distance as a radius, and the first point may be a longest point from the current location on the circle. 
     The control unit may calculate an altitude of the target by using an altitude of the current location, the distance to the target, and the tilt angle, and may calculate a horizontal distance to the target when the altitude of the target is included between the altitude of the hole obtained from the map information and a sum of a predetermined height and the altitude of the hole. 
     The control unit may output a message for guiding re-measurement to the output unit when the horizontal distance is outside the first distance. 
     The present invention has been made in an effort to provide a control method of a distance measuring apparatus, including: acquiring, by a location acquiring sensor, a current location of the distance measuring apparatus; 
     reading out, by a control unit, map information of golf courses corresponding to the current location from a memory in which the map information of the golf courses is stored; measuring, by a distance measuring sensor, a distance to a target; measuring, by a slope sensor, a sloped tilt angle; calculating, by the control unit, a horizontal distance to the target by using the distance to the target and the tilt angle; calculating, by the control unit, a first distance from the current location to a first point of the golf course; and outputting, by the control unit, the horizontal distance when the horizontal distance is within a first distance. 
     The control method may further include: measuring, by an azimuth sensor, an azimuth to which the distance measuring apparatus is directed; and outputting, by the control unit, the horizontal distance when the azimuth is included in a range between a first azimuth in a direction connecting a second point of the golf course from the current location and a second azimuth in a direction of connecting a third point of the golf course from the current location. 
     The second point and the third point may be two points where an arc and two radii of the fan having the first distance as a length of a radius thereof meet each other when a length of the arc of the fan satisfies a predetermined length. 
     A central angle of the fan is bisected by a connection line between the current location and the first point. 
     The second point and the third point may be two points where two tangent lines from the current location to the green of the golf course contact the green. 
     The first point may be a longest point from the current location on the green of the golf course. 
     The calculating the first distance includes calculating, by the control unit, a second distance from the current location to a fourth point of the golf course, the outputting the horizontal distance includes outputting, by the control unit, the horizontal distance when the horizontal distance is included in a range between the first distance and the second distance, and the fourth point is a shortest point from the current location on the green of the golf course. 
     The second point and the third point may be two points that are in contact with a circle centered on the central point of the green of the golf course from the current position and having a predetermined distance as a radius, and the first point may be a longest point from the current location on the circle. 
     The control method may further include: before the calculating the horizontal distance, calculating, by the control unit, an altitude of the target by using an altitude of the current location, the distance to the target, and the tilt angle; and calculating, by the control unit, a horizontal distance to the target when the altitude of the target is included between the altitude of the hole obtained from the map information and a sum of a predetermined height and the altitude of the hole. 
     The control method may further include outputting, by the control unit, a message for guiding re-measurement to the output unit when the horizontal distance is outside the first distance. 
     Advantageous Effects 
     The effects of the distance measuring apparatus and the control method thereof according to the present disclosure will be described as follows. 
     According to at least one of the embodiments of the present disclosure, a golfer can easily check a location of a hole. 
     According to at least one of the embodiments of the present disclosure, a golfer can easily check a distance to a hole. 
     The additional range of applicability of the present disclosure will become apparent from the following detailed description. However, since various modifications and alternatives within the spirit and scope of the present disclosure may be clearly understood by those skilled in the art, it is to be understood that a detailed description and a specific exemplary embodiment of the present invention are provided only by way of example. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a block diagram for describing a distance measuring apparatus according to an exemplary embodiment. 
         FIG. 2  and  FIG. 3  illustrate schematic diagrams of examples of a distance measuring apparatus viewed in different directions according to an exemplary embodiment. 
         FIG. 4  illustrates a schematic structural diagram of an optical unit and a distance measuring sensor of a distance measuring apparatus according to an exemplary embodiment. 
         FIG. 5  illustrates a flowchart of a control method of a distance measuring apparatus according to a first exemplary embodiment. 
         FIG. 6  illustrates an example of searching for a pin depending on the control method of  FIG. 5 . 
         FIG. 7  illustrates a flowchart of a control method of a distance measuring apparatus according to a second exemplary embodiment. 
         FIG. 8  and  FIG. 9  illustrate examples of searching for a pin depending on the control method of  FIG. 7 . 
         FIG. 10  illustrates a flowchart of a control method of a distance measuring apparatus according to a third exemplary embodiment. 
         FIG. 11  illustrates an example of searching for a pin depending on the control method of  FIG. 10 . 
         FIG. 12  illustrates a flowchart of a control method of a distance measuring apparatus according to a fourth exemplary embodiment. 
         FIG. 13  illustrates an example of searching for a pin depending on the control method of  FIG. 12 . 
     
    
    
     MODE FOR INVENTION 
     Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings. In the present specification, the same or similar components will be denoted by the same or similar reference numerals, and a repeated description thereof will be omitted. Terms “module” and “unit” for components used in the following description are used only in order to easily describe the specification. Therefore, these terms do not have meanings or roles that distinguish them from each other in and of themselves. In describing exemplary embodiments of the present specification, when it is determined that a detailed description of the well-known art associated with the present invention may obscure the gist of the present invention, it will be omitted. The accompanying drawings are provided only in order to allow exemplary embodiments disclosed in the present specification to be easily understood and are not to be interpreted as limiting the spirit disclosed in the present specification, and it is to be understood that the present invention includes all modifications, equivalents, and substitutions without departing from the scope and spirit of the present invention. 
     Terms including ordinal numbers such as first, second, and the like will be used only to describe various components, and are not to be interpreted as limiting these components. The terms are only used to differentiate one component from other components. 
     It is to be understood that when one component is referred to as being “connected” or “coupled” to another component, it may be connected or coupled directly to the other component or be connected or coupled to the other component with a further component intervening therebetween. Further, it is to be understood that when one component is referred to as being “directly connected” or “directly coupled” to another component, it may be connected or coupled directly to the other component without a further component intervening therebetween. 
     It will be further understood that terms “comprises” and “have” used in the present specification specify the presence of stated features, numerals, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, numerals, steps, operations, components, parts, or combinations thereof. 
       FIG. 1  illustrates a block diagram for describing a distance measuring apparatus  100  according to an exemplary embodiment, and  FIG. 2  and  FIG. 3  illustrate schematic diagrams of examples of the distance measuring apparatus  100  viewed in different directions according to an exemplary embodiment. 
     The distance measuring apparatus  100  may include a sensing unit  110 , an optical unit  120 , a user input unit  130 , an interface unit  140 , an output unit  150 , a memory  160 , a wireless communication unit  170 , a control unit  180 , a power supply unit  190 , and the like. The constituent elements shown in  FIG. 1  are not essential for implementing the distance measuring apparatus  100 , so the distance measuring apparatus  100  described in the present specification may include more or less constituent elements than the foregoing listed constituent elements. 
     More particularly, among the constituent elements, the sensing unit  110  may include one or more sensors for sensing at least one of information on an environment surrounding the distance measuring apparatus  100  and information within the distance measuring apparatus  100 . For example, the sensing unit  110  may include at least one of a distance measuring sensor  111 , a location acquiring sensor  112 , an acceleration sensor  113 , an azimuth sensor  114 , a gyroscope sensor, a battery gauge, and an environment sensor (for example, a barometer, a hydrometer, and a thermometer). In the meantime, the distance measuring apparatus  100  disclosed in the present specification may utilize a combination of information sensed by at least two or more sensors among the sensors. 
     First, the distance measuring sensor  111  refers to a sensor which measures a distance to a target. The distance measuring sensor  111  may include an ultrasonic sensor, an infrared sensor (IR sensor), a laser sensor, a radio detecting and ranging sensor (radar sensor), an optical sensor (for example, a camera), and the like. The distance measuring sensor  111  is not limited to the listed kinds of sensors, and includes all kinds of sensors measuring a distance to a target. 
     Hereinafter, it is assumed that the distance measuring sensor  111  is a laser sensor, which transmits a laser in a front direction and receives a laser reflected from a target to measure a distance to the target. 
     The location acquiring sensor  112  is a sensor for acquiring a location of the distance measuring apparatus  100 , and a representative example of the location acquiring sensor  112  is a global positioning system (GPS) sensor. The GPS sensor calculates distance information from three or more separate satellites and accurate time information and then applies trigonometry to the calculated information, thereby accurately calculating 3D current location information according to the latitude, the longitude, and the altitude. Currently, a method of calculating location and time information by using three satellites and correcting errors of the calculated location and time information by using one other satellite is widely used. Further, the GPS sensor may calculate speed information by continuously calculating a current location in real time. 
     A slope sensor  113  may acquire the degree of tilt of the distance measuring apparatus  100 . The slope sensor  113  may include an acceleration sensor (accelerometer) measuring gravitational acceleration. Further, the slope sensor  113  may also be implemented by a scheme of calculating a tilt by using a rotation angle in a vertical direction from a predetermined reference direction acquired by a gyro sensor, and the like. 
     The azimuth sensor  114  is a sensor measuring an azimuth, and may acquire a value of an azimuth to which the distance measuring apparatus  100  is directed. The azimuth sensor  114  may be a geomagnetic sensor, which detects the earth&#39;s magnetic field and measures an azimuth. Further, the azimuth sensor  114  may also be implemented by a scheme of calculating an azimuth by using a rotation angle in a horizontal direction from a predetermined reference direction acquired by a gyro sensor, and the like. 
     The optical unit  120  has a structure for receiving external light, and may include a lens unit, a filter unit, and the like. The optical unit  120  optically processes light from a subject. 
     The lens unit may include a zoom lens, a focusing lens, a compensating lens, and the like, and the filter unit may include an ultraviolet filter (UV filter), an optical low pass filter, and the like. 
     ext, the user input unit  130  receives input of information from a user, and when information is input through the user input unit  130 , the control unit  180  may control an operation of the distance measuring apparatus  100  so as to correspond to the input information. The user input unit  130  may include a mechanical input means (for example, a mechanical key, a button located on a front surface, a rear surface, or a lateral surface of the distance measuring apparatus  100 , a dome switch, a jog wheel, and a jog switch) and a touch-type input means. For example, the touch-type input means may be formed of a virtual key, a soft key, or a visual key displayed on a touch screen through software processing, or a touch key disposed in a portion other than the touch screen. In the meantime, the virtual key or the visual key may be displayed on the touch screen with various forms, and for example, the virtual key or the visual key may be formed of a graphic, a text, an icon, a video, or a combination thereof. 
     The interface unit  140  serves as a passage of various kinds of external devices connected with the distance measuring apparatus  100 . The interface unit  140  may include at least one of an external charger port, a wired/wireless data port, and a memory  160  card port. The distance measuring apparatus  100  may perform appropriate control related to the connected external device in response to the connection of the external device to the interface unit  140 . 
     The output unit  150  generates an output related to a visual sense, an auditory sense, or a tactile sense, and may include a display unit  151 , a sound output unit  152 , a vibration output unit  153 , and the like. 
     The display unit  151  displays (outputs) information processed by the distance measuring apparatus  100 . For example, the display unit  151  may display execution image information of an application program driven in the distance measuring apparatus  100 , or user interface (UI) and graphical user interface (GUI) information according to the execution image information. 
     The display unit  151  may include at least one of a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT LCD), an organic light-emitting diode (OLED), and an e-ink display. 
     In addition, two or more display units  151  may exist according to an implementation form of the distance measuring apparatus  100 . In this case, the plurality of display units  151  may be disposed together on an external surface of the distance measuring apparatus  100  and in an internal portion of the distance measuring apparatus  100 , or the plurality of display units  151  may be individually disposed on an external surface of the distance measuring apparatus  100  and in an internal portion of the distance measuring apparatus  100 , respectively. 
     A display unit  151   a  disposed on the external surface of the distance measuring apparatus  100  may include a touch sensor, which detects a touch to the display unit  151   a,  so as to receive an input of a control command by a touch scheme. When a touch is input to the display unit  151   a  by using the display unit  151   a,  the touch sensor may detect the touch, and the control unit  180  may generate a control command corresponding to the touch based on the detected touch. Contents input by the touch scheme may be letters or numbers, or may be menu items indicatable or designable in various modes. 
     A display unit  151   b  disposed in the internal portion of the distance measuring apparatus  100  may display an image to a user through an ocular lens  121  of the distance measuring apparatus  100 . The display unit  151   b  disposed in the internal portion of the distance measuring apparatus  100  includes a transparent display (or a semi-transparent display), which is directly located on an optical path of the ocular lens  121 . A representative example of the transparent display is a transparent OLED (TOLED). Further, the display unit  151   b  disposed in the internal portion of the distance measuring apparatus  100  may be an opaque display, which provides an image to the optical path of the ocular lens  121  through an optical member having a function of refracting or reflecting light and the like. 
     The sound output unit  152  may output audio data stored in the memory  160  in the form of a sound, and may be implemented in the form of a loudspeaker, which outputs various alarm sounds or a playback sound of multimedia. 
     The vibration output unit  153  generates various tactile effects that the user may feel. Intensity, a pattern, and the like of the vibration generated by the vibration output unit  153  may be controlled by a selection of the user or a setting of the control unit  180 . For example, the vibration output unit  153  may also combine and output different vibrations or sequentially output different vibrations. 
     In addition, the output unit  150  may further include a light output unit, which outputs a signal notifying of generation of an event by using light of a light source. 
     Further, the memory  160  stores data (for example, the data includes course map information about a tee box, a fairway, a hazard, a bunker, a rough, a green, a hole of a golf course, and the like, but is not limited thereto) supporting various functions of the distance measuring apparatus  100 . The memory  160  may store firmware and an application program driven in the distance measuring apparatus  100  and data and commands for an operation of the distance measuring apparatus  100 . At least some of the application programs may be installed in the distance measuring apparatus  100  at the time of shipment for the basic function of the distance measuring apparatus  100 . Further, at least some of the application programs may be downloaded from an external server through wireless communication. In the meantime, the application program may be stored in the memory  160  and is installed in the distance measuring apparatus  100 , thereby being driven so as to perform the operation (or the function) of the distance measuring apparatus  100  by the control unit  180 . 
     The wireless communication unit  170  may include one or more modules, which are capable of establishing wireless communication between the distance measuring apparatus  100  and a wireless communication system, the distance measuring apparatus  100  and other available wireless communication devices, or the distance measuring apparatus  100  and an external server. 
     The wireless communication unit  170  may include a wireless Internet module  171  and a short range communication module  172 . 
     The wireless Internet module  171  refers to a module for wireless Internet connection, and may be embedded in the distance measuring apparatus  100 . The wireless Internet module  171  is configured to transmit and receive wireless signals in a communication network according to wireless Internet technologies. The wireless Internet module  171  transceives a wireless signal in a communication network according to the wireless Internet technologies. Examples of the wireless Internet technology include a Wireless Local Area Network (WLAN), Wireless Fidelity (Wi-Fi), Wi-Fi Direct, Digital Living Network Alliance (DLNA), Wireless Broadband (WiBro), World Interoperability for Microwave Access (WiMAX), High Speed Downlink Packet Access (HSDPA), High Speed Uplink Packet Access (HSUPA), Long Term Evolution (LTE), and Long Term Evolution-Advanced (LTE-A), and the wireless Internet module  171  transceives data according to at least one wireless Internet technology in a range including Internet technology which is not listed above. 
     The short range communication module  172  is for short range communication, and may support short range communication by using at least one of BluetoothTM, Radio Frequency Identification (RFID), Infrared Data Association (IrDA), Ultra Wideband (UWB), ZigBee, Near Field Communication (NFC), Wi-Fi, Wi-Fi direct, and Wireless Universal Serial Bus (USB) technologies. The short range communication module  172  may support wireless communication between the distance measuring apparatus  100  and a wireless communication system, the distance measuring apparatus  100  and a wireless communication available device, or the distance measuring apparatus  100  and a network, in which an external server is located, through a wireless area network. The wireless area network may be a wireless personal area network. 
     Herein, the wireless communication available device may be a wearable device (for example, a smart watch and smart glasses) which is capable of exchanging (interlocking) data with the distance measuring apparatus  100  according to the present invention. The short range communication module  172  may detect (or recognize) a wearable device which is capable of communicating with the distance measuring apparatus  100 , around the distance measuring apparatus  100 . Further, when the detected wearable device is a device authenticated to communicate with the distance measuring apparatus  100  according to the exemplary embodiment, the control unit  180  may transmit at least a part of the data processed in the distance measuring apparatus  100  to the wearable device through the short range communication module  172 . Accordingly, a user of the wearable device may use the data processed in the distance measuring apparatus  100  through the wearable device. 
     The control unit  180  generally controls an overall operation of the distance measuring apparatus  100  in addition to the operation related to the application program. The control unit  180  processes the input or output signal, data, information, and the like, or drives the application program stored in the memory  160  through the foregoing constituent elements, thereby providing the user with or processing the appropriate information or function. 
     Further, the control unit  180  may control at least a part of the constituent elements described with reference to  FIG. 1  in order to drive the application program stored in the memory  160 . Further, the control unit  180  may combine two or more of the constituent elements included in the distance measuring apparatus  100  and operate the combined constituent elements for driving the application program. 
     The power supply unit  190  receives power from an external power source and an internal power source, and supplies the power from the power source to each constituent element included in the distance measuring apparatus  100  under the control of the control unit  180 . The power supply unit  190  includes a battery, and the battery may be an embedded battery or a replaceable battery. 
     At least a part of the constituent elements may cooperate with each other and be operated for operating, controlling, or implementing a method for controlling the distance measuring apparatus  100  according to various exemplary embodiments described below. Further, the operation, the control, or the method for controlling the distance measuring apparatus  100  may be implemented in the distance measuring apparatus  100  through driving of at least one application program stored in the memory  160 . 
     Referring to  FIGS. 2 and 3 , the disclosed distance measuring apparatus  100  includes a body having the form of a column, of which a front surface and a rear surface have oval track shapes. However, the present invention is not limited thereto, and is applicable to various structures, such as a watch type, a clip type, a glasses type, or a slide type, and a swing type and a swivel type in which two or more bodies are combined to be relatively movable. The form of the body may be related to a specific type of distance measuring apparatus  100 , but a description of the specific type of distance measuring apparatus  100  may be generally applied to a distance measuring apparatus  100  of other types. 
     Herein, the body may be understood as a concept of the distance measuring apparatus  100  being considered as at least one assembly. 
     The distance measuring apparatus  100  includes a case (for example, a frame, a housing, and a cover) configuring an exterior appearance. As shown, the distance measuring apparatus  100  may include a front case  101 , a middle case  102 , and a rear case  103 . Various electronic components are disposed in an internal space formed by a combination of the front case  101 , the middle case  102 , and the rear case  103 . 
     The cases may be formed by injecting a synthetic resin or may be formed of a metal, for example, stainless steel (STS), aluminum (Al), and titanium (Ti), and external portions of the cases may also be covered with leather, rubber, and the like. 
     An ocular lens  121 , a first operation unit  130   a,  a second operation unit  130   b,  and a display unit  151   a  may be disposed in the front case  101 . In this case, the first operation unit  130   a  may be disposed in the form of a jog wheel in a circumference of the ocular lens  121 , thereby protecting the ocular lens  121 . 
     A third operation unit  130   c  and a fourth operation unit  130   d  may be disposed on one surface of the middle case  102 . The user may conveniently operate the third operation unit  130   c  and the fourth operation unit  130   d  while holding the distance measuring apparatus  100 . 
     One or more object lens  122  and  123  may be disposed in the rear case  103 . The object lens  122  and  123  may receive light from the outside. For example, the object lens  122  located at the upper side may receive light from a subject to enable the user to check the subject by eye through the ocular lens  121 . When the laser emitted from the distance measuring apparatus  100  is reflected from the target, the object lens  123  located at the lower side may receive the reflected laser. 
     The configurations are not limited to the foregoing disposition. The configurations may be excluded or replaced as necessary, or may be disposed in other surfaces. For example, the display unit  151   a  and the second operation unit  130   b  may not be provided in the front surface of the body, and the number of operation units  130   a,    130   b,    130   c,  and  130   d  may be changed. 
     Next, the optical unit  120  and the distance measuring sensor  111  of the distance measuring apparatus  100  will be described in detail with reference to  FIG. 4 . 
       FIG. 4  is a schematic structural diagram of the optical unit  120  and the distance measuring sensor  111  of the distance measuring apparatus  100  related to one exemplary embodiment. 
     The distance measuring apparatus  100  according to one exemplary embodiment includes the two object lens  122  and  123 , one ocular lens  121 , a light path changing unit  126 , a light processing unit  124 , the display unit  151   a,  a laser generating unit  1110 , a laser receiving unit  1111 , a laser control unit  1112 , and the control unit  180 . 
     Through the first object lens  122 , external light OL may be incident to the distance measuring apparatus  100 , or a laser L 1  generated in the laser generating unit  1110  may be emitted to the outside. A path of the laser L 1  generated in the laser generating unit  1110  may be changed through the light path changing unit  126  so that the laser L 1  heads to the first object lens  122 . 
     The external light OL passes through the first object lens  122  and the light path changing unit  126  to be incident to the light processing unit  124 . The light processing unit  124  includes a lens unit and a filter unit. The external light OL incident to the light processing unit  124  is optically processed and heads to the ocular lens  121  side. The lens unit processes light according to the driving of a driving unit  125 . For example, when the user operates the first operation unit  130   a  and the like, the driving unit  125  is driven and a zoom lens moves, so that a zoom-in or zoom-out operation is performed. 
     Through the second object lens  123 , a laser L 2  reflected from the target may be incident to the distance measuring apparatus  100 . The laser receiving unit  1111  receives the laser L 2  incident through the second object lens  123 , and outputs a corresponding signal to the laser control unit  1112 . 
     Then, the laser control unit  1112  may calculate a distance from the distance measuring apparatus  100  to the target by using the signal received from the laser receiving unit  1111 . The calculated distance value is output to the control unit  180 . 
     The display unit  151   b  may be formed of a transparent or semi-transparent display and be directly disposed in a path through which the external light OL passes. Otherwise, the display unit  151   b  may provide an image to the optical path of the ocular lens  121  through an optical member having a function of refracting or reflecting light and the like. 
     Hereinafter, a control method implementable by the distance measuring apparatus  100  formed as described above and relevant exemplary embodiments will be described with reference to the accompanying drawings. It is obvious to those skilled in the art that the present invention may be embodied in another specific form within a range of a spirit and an essential characteristic of the present invention. 
     A control method of the distance measuring apparatus  100  according to a first exemplary embodiment will be described with and to  FIG. 5  and  FIG. 6 . 
       FIG. 5  illustrates a flowchart of a control method of the distance measuring apparatus according to the first exemplary embodiment, and  FIG. 6  illustrates an example of searching for a pin depending on the control method of  FIG. 5 . 
     First, the location acquiring sensor  112  acquires coordinates of a current location  600  (S 100 ). The location acquiring sensor  112  may acquire coordinates of the current location  600  of the distance measuring apparatus  100 . The control unit  180  reads course map information corresponding to the coordinates of the current location  600  from the memory  160  (S 102 ). The course map information includes location coordinates indicating a boundary GB of the green of the golf course including the coordinates of the current location  600 . 
     The distance measuring sensor  111  measures a straight line distance from the distance measuring apparatus  100  to a target (one of  601 ,  602 , and  603 ) (S 104 ), and the slope sensor  113  measures an angle of tilt (hereinafter referred to as a tilt angle) in which the distance measuring apparatus  100  is directed to the target (S 106 ). 
     Then, the control unit  180  calculates a horizontal distance from the distance measuring apparatus  100  to the target according to Equation 1 by using the measured straight line distance and the tilt angle (S 108 ). 
         L=D ×cos TA   (Equation 1)
 
     In Equation 1, L indicates a horizontal distance from the distance measuring apparatus  100  to the target, D indicates a straight line distance measured by the distance measuring sensor  111 , and TA indicates a tilt angle. 
     The control unit  180  calculates a first distance BD 1  and a second distance BD 2  by using the coordinates of the current position  600  and location coordinates indicating a boundary GB 1  of the green (S 110 ). 
     For example, the control unit  180  may calculate a distance to a point BP 01  located at a closest distance from the current location  600  in the boundary GB of the green as the first distance BD 1 , and may calculate a distance to a point BP 02  located at a farthest distance from the current location  600  in the boundary GB of the green as the second distance BD 2 . 
     The control unit  180  determines whether the calculated horizontal distance (one of MD 1 , MD 2 , and MB 3 ) is greater than the first distance BD 1  and smaller than the second distance BD 2  (S 112 ). 
     For the first horizontal distance MD 1 , it is determined that it is greater than the first distance BD 1  and smaller than the second distance BD 2 . For the second horizontal distance MD 2 , it is determined that it is smaller than the first distance BD 1 . For the third horizontal distance MD 3 , it is determined that it is greater than the second distance BD 2 . 
     The control unit  180  outputs the horizontal distance MD 1  by using the output unit  150  when the calculated horizontal distance MD 1  is greater than the first distance BD 1  and smaller than the second distance BD 2  (S 114 ). 
     For example, the control unit  180  may display the horizontal distance MD 1  on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration indicating that the pin is present at the horizontal distance MD 1  by using the vibration output unit  153 . 
     The control unit  180  outputs a message for guiding distance re-measurement by using the output unit  150  when the calculated horizontal distance MD 2  or MD 3  is smaller than the first distance BD 1  or greater than the second distance BD 2  (S 116 ). 
     For example, the control unit  180  may display the message for guiding the distance re-measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the distance re-measurement using by the vibration output unit  153 . 
     According to the control method of the distance measuring apparatus  100  as described above, a user can easily check a hole location and a distance from the current location to the hole. 
     Next, a control method of the distance measuring apparatus  100  according to a second exemplary embodiment will be described with reference to  FIG. 7  to  FIG. 9 . 
       FIG. 7  illustrates a flowchart of the control method of the distance measuring apparatus  100  according to the second exemplary embodiment, and  FIG. 8  and  FIG. 9  illustrate examples of searching for a pin depending on the control method of  FIG. 7 . 
     First, the location acquiring sensor  112  acquires a current location (S 200 ). The location acquiring sensor  112  may acquire coordinates of the current location of the distance measuring apparatus  100 . 
     The control unit  180  reads course map information corresponding to the coordinates of the current location from the memory  160  (S 202 ). The course map information includes location coordinates indicating a predetermined point on the green of the golf course including the coordinates of the current location. 
     The predetermined point, which is a point on the green located on the corresponding golf course, may be, e.g., a point BP located farthest from a pin  801  along a predetermined direction among boundaries of the green of each golf course as illustrated in  FIG. 8 . Alternatively, the predetermined point may be a central point CP of the green of each golf course, as illustrated in  FIG. 9 . The central point CP may be a predetermined point for each golf course. The central point CP may be a different location from a pin  901 . 
     The central point CP has coordinates including medians of x-axis coordinates and medians of y-axis coordinates among coordinates of the green on a plane formed by two intersecting axes (e.g., x-axis and y-axis). Alternatively, the central point CP may have coordinates including averages of x-axis coordinates and average values of y-axis coordinates among the coordinates of the green. 
     The control unit  180  calculates a second distance from the current position to a predetermined point (S 204 ). 
     As an example, as illustrated in  FIG. 8 , when the current location is a point  800 , the control unit  180  may calculate a distance RL 1  from the current location  800  to the point BP as the second distance. In addition, when the current location is a point  810 , the control unit  180  may calculate a distance RL 2  from the current location  810  to the point BP as the second distance. 
     As another example, as illustrated in  FIG. 9 , when the current location is a point  900 , the control unit  180  may calculate a longest distance RL 3  from the current location  900  to a circle GC centering on a point CP as the second distance. In this case, the circle GC may have a radius R 2  of a predetermined length (e.g., 10 to 20 m). In addition, when the current location is a point  910 , the control unit  180  may calculate a longest distance RL 4  from the current location  910  to the circle GC centering on the point CP as the second distance. 
     Next, the control unit  180  calculates the first azimuth and the second azimuth (S 206 ). 
     For example, as illustrated in  FIG. 8 , when the current location is a point  800 , the control unit  180  calculates a central angle of a fan  820  having the distance RL 1  as a radius length in the case where a length of an arc AD of the fan  820  satisfies a specific length (e.g., 30 to 50 m). In addition, the control unit  180  respectively calculates azimuths of two radii R 11  and R 12  of the fan  820  as the first azimuth and the second azimuth when a line connecting the current location  800  to the point BP bisects a central angle of the fan  820  (including the case of generally bisecting it, including the case that BA 11  and BA 12  have exactly the same value or have different values within a 1 degree range). 
     In addition, when the current location is a point  810 , the control unit  180  calculates a central angle of a fan  830  having the distance RL 2  as a radius length in the case where a length of an arc AL 2  of the fan  830  satisfies a specific length. In addition, the control unit  180  respectively calculates azimuths of two radii R 13  and R 14  of the fan  830  as the first azimuth and the second azimuth when a line connecting the current location  810  to the point BP bisects a central angle of the fan  830  (including the case of generally bisecting it, including the case that BA 13  and BA 14  have exactly the same value or have different values within a 1 degree range). 
     As another example, as illustrated in  FIG. 9 , when the current location is a point  900 , the control unit  180  respectively calculates the azimuths of two tangent lines BL 11  and BL 12  from the current location  900  to a circle GC as the first azimuth and the second azimuth. 
     In addition, when the current location is a point  910 , the control unit  180  respectively calculates the azimuths of two tangent lines BL 21  and BL 22  from the current location  910  to the circle GC as the first azimuth and the second azimuth. 
     The azimuth sensor  114  measures an azimuth in a direction in which the distance measuring apparatus  100  faces (S 208 ). 
     The control unit  180  determines whether the measured azimuth is included in a range of the first azimuth to the second azimuth (S 210 ). In this case, the range of the first azimuth to the second azimuth indicates a range in which an angle formed by the first azimuth to the second azimuth is 180 degrees or less. 
     When the measured azimuth is included in the range of the first azimuth to the second azimuth, the control unit  180  may display a message for guiding distance measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding distance measurement using by the vibration output unit  153 . 
     The control unit  180  outputs a message for guiding target adjustment by using the output unit  150  when the measured azimuth is not included in the first azimuth to the second azimuth (S 214 ). For example, the control unit  180  may display the message for guiding the target adjustment on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the target adjustment using by the vibration output unit  153 . 
     Next, the distance measuring sensor  111  measures a straight line distance from the distance measuring apparatus  100  to a target (S 212 ), and the slope sensor  113  measures a tilt angle of the distance measuring apparatus  100  (S 216 ). 
     Then, the control unit  180  calculates a horizontal distance from the distance measuring apparatus  100  to the target according to Equation 1 by using the measured straight line distance and the tilt angle (S 218 ). 
     The control unit  180  determines whether the horizontal distance is smaller than the second distance (S 220 ). 
     The control unit  180  outputs the horizontal distance by using the output unit  150  when the calculated horizontal distance is smaller than the second distance (S 222 ). 
     For example, the control unit  180  may display the horizontal distance on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration indicating that the pin is present at the measured horizontal distance using the vibration output unit  153 . 
     The control unit  180  outputs a message guiding distance re-measurement by using the output unit  150  when the calculated horizontal distance is greater than or equal to the second distance (S 224 ). For example, the control unit  180  may display the message for guiding the distance re-measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the distance re-measurement using by the vibration output unit  153 . 
     According to the control method of the distance measuring apparatus  100  as described above, a user can easily check a hole location and a distance from the current location to the hole. 
     Next, a control method of the distance measuring apparatus  100  according to a third exemplary embodiment will be described with and to  FIG. 10  and  FIG. 11 . 
       FIG. 10  illustrates a flowchart of a control method of the distance measuring apparatus  100  according to a third exemplary embodiment, and  FIG. 11  illustrates an example of searching for a pin depending on the control method of  FIG. 10 . 
     First, the location acquiring sensor  112  acquires coordinates of a current location  1000  (S 300 ). The location acquiring sensor  112  may acquire coordinates of the current location  1000  of the distance measuring apparatus  100 . 
     The control unit  180  reads course map information corresponding to the coordinates of the current location  1000  from the memory  160  (S 302 ). The course map information includes location coordinates indicating a boundary GB of the green of the golf course including the coordinates of the current location  1000 . 
     Then, the control unit  180  calculates the first azimuth and the second azimuth (S 304 ). 
     For example, the control unit  180  calculates azimuths of two tangent lines from a current location  1000  to two contact points BP 1  and BP 2  of a boundary GB of the green as the first azimuth and the second azimuth, respectively. In this case, the two contact points BP 1  and BP 2  may correspond to two contact points between the boundary GB of the green and the two tangent lines, respectively, from the current location  1000 . 
     The azimuth sensor  114  measures an azimuth in a direction in which the distance measuring apparatus  100  faces (S 306 ). 
     The control unit  180  determines whether the measured azimuth is included in a range of a first azimuth BA 1  to a second azimuth BA 2  (S 308 ). In this case, the range of the first azimuth BA 1  to the second azimuth BA 2  indicates a range in which an angle formed by the first azimuth BA 1  to the second azimuth BA 2  is 180 degrees or less. 
     When the measured azimuth is included in the range of the first azimuth BA 1  to the second azimuth BA 2 , the control unit  180  may display a message for guiding distance measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding distance measurement using by the vibration output unit  153 . 
     The control unit  180  outputs a message for guiding target adjustment by using the output unit  150  when the measured azimuth is not included in the first azimuth BA 1  to the second azimuth BA 2  (S 312 ). Specifically, the control unit  180  may display the message for guiding the target adjustment on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the target adjustment using by the vibration output unit  153 . 
     Further, when the distance measuring apparatus  100  faces a target  1002 , the control unit  180  determines that an azimuth in a direction of the target  1002  is not included in the first azimuth BA 1  to the second azimuth BA 2 , and a horizontal distance MD 2  from the distance measuring apparatus  100  to the target  1002  may not be calculated. 
     The distance measuring sensor  111  measures a straight line distance from the distance measuring apparatus  100  to a target  1001  (S 310 ), and the slope sensor  113  measures a tilt angle of the distance measuring apparatus  100  (S 314 ). 
     Then, the control unit  180  calculates a horizontal distance MD 1  from the distance measuring apparatus  100  to the target according to Equation 1 by using the measured straight line distance and the tilt angle (S 316 ). 
     The control unit  180  calculates a first distance BD 1  and a second distance BD 2  by using the coordinates of the current position  1000  and location coordinates indicating a boundary GB 1  of the green (S 318 ). 
     For example, the control unit  180  may calculate a distance to a point BP 01  located at a closest distance from the current location  1000  in the boundary GB of the green as the first distance BD 1 , and may calculate a distance to a point BP 02  located at a farthest distance from the current location  1000  in the boundary GB of the green as the second distance BD 2 . 
     The control unit  180  determines whether the calculated horizontal distance MD 1  is greater than the first distance BD 1  and smaller than the second distance BD 2  (S 320 ). 
     The control unit  180  outputs the horizontal distance MD 1  by using the output unit  150  when the calculated horizontal distance MD 1  is greater than the first distance BD 1  and smaller than the second distance BD 2  (S 322 ). 
     For example, the control unit  180  may display the horizontal distance MD 1  on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration indicating that the pin is present at the horizontal distance MD 1  by using the vibration output unit  153 . 
     The control unit  180  outputs a message for guiding distance re-measurement by using the output unit  150  when the calculated horizontal distance is smaller than the first distance BD 1  or greater than the second distance BD 2  (S 324 ). 
     For example, the control unit  180  may display the message for guiding the distance re-measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the distance re-measurement using by the vibration output unit  153 . 
     According to the control method of the distance measuring apparatus  100  as described above, a user can easily check a hole location and a distance from the current location to the hole. 
     Next, a control method of the distance measuring apparatus  100  according to a fourth exemplary embodiment will be described with and to  FIG. 12  and  FIG. 13 . 
       FIG. 12  illustrates a flowchart of a control method of the distance measuring apparatus  100  according to a fourth exemplary embodiment, and  FIG. 13  illustrates an example of searching for a pin depending on the control method of  FIG. 12 . 
     First, the location acquiring sensor  112  acquires a current location (S 200 ). The location acquiring sensor  112  may acquire coordinates of the current location of the distance measuring apparatus  100 . In particular, the location acquiring sensor  112  may acquire information related to an altitude of the current location. 
     The control unit  180  reads course map information corresponding to the coordinates of the current location from the memory  160  (S 202 ). The course map information may include information related to an altitude of the green of the golf course including the coordinates of the current location, location coordinates indicating the boundary of the green, and the like. 
     The distance measuring sensor  111  measures a straight line distance MD 11  from the distance measuring apparatus  100  to a target  200  (S 404 ), and the slope sensor  113  measures a tilt angle TA 1  of the distance measuring apparatus  100  (S 406 ). 
     Then, the control unit  180  calculates an altitude of the target  200  from the distance measuring apparatus  100  by using Equation 2 using the measured straight distance MD 11  and the tilt angle TA 1  (S 408 ). 
         h 01= MD 1×sin  TA 1   (Equation 2)
 
     In Equation 2, h 01  indicates an altitude difference from the distance measuring apparatus  100  to the target, MD 1  indicates a straight line distance TA 1  measured by the distance measuring sensor  111 , and TA indicates a tilt angle. 
     The control unit  180  may calculate an altitude of the target  200  by adding the altitude difference h 01  from the distance measuring apparatus  100  to the target  200  to an altitude H 0  of the distance measuring apparatus  100 . 
     Next, the control unit  180  determines whether the altitude of the target  200  is included in a range of a first altitude to a second altitude (S 410 ). The first altitude includes an altitude H 1  of the hole obtained from information related to an altitude of the green of the golf course read in step S 402 , and the second altitude includes an altitude plus a height h 11  of the pin from the first altitude. In addition, the first altitude and the second altitude may be a highest altitude and a lowest altitude of the green altitudes, respectively. A method of determining the first altitude and the second altitude is not limited to the above description. 
     When the altitude of the target  200  is included in a range of a first altitude to a second altitude, the control unit  180  calculates a horizontal distance L 11  from the distance measuring apparatus  100  to the target according to Equation 1 by using the measured straight line distance and the tilt angle (S 412 ). 
     The control unit  180  outputs a message guiding target adjustment by using the output unit  150  when the altitude of the target  200  is not included in the range of the first altitude to the second altitude (S 414 ). For example, the control unit  180  may display the message for guiding the target adjustment on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the target adjustment using by the vibration output unit  153 . 
     The control unit  180  calculates a first distance and a second distance by using the coordinates of the current position and location coordinates indicating a boundary of the green (S 416 ). A description of step S 416  is the same as step S 112  or step S 318  described above, so the description will be omitted. The control unit  180  determines whether the calculated horizontal distance L 11  is greater than the first distance and smaller than the second distance (S 418 ). 
     The control unit  180  outputs the horizontal distance L 11  by using the output unit  150  when the calculated horizontal distance L 11  is greater than the first distance and smaller than the second distance (S 420 ). 
     For example, the control unit  180  may display the horizontal distance L 11  on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration indicating that the pin is present at the horizontal distance L 11  by using the vibration output unit  153 . 
     The control unit  180  outputs a message for guiding distance re-measurement by using the output unit  150  when the calculated horizontal distance L 11  is smaller than the first distance or greater than the second distance. 
     For example, the control unit  180  may display the message for guiding the distance re-measurement on the display unit  151  or may output it as a sound by using the sound output unit  152 . In addition, the control unit  180  may output a vibration of a sequence for guiding the distance re-measurement using by the vibration output unit  153 . 
     According to the control method of the distance measuring apparatus  100  as described above, a user can easily check a hole location and a distance from the current location to the hole. 
     While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.