Patent Publication Number: US-2016231977-A1

Title: Display device for vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on Japanese Patent Application (No. 2015-021973) filed on Feb. 6, 2015 and Japanese Patent Application (No. 2015-246998) filed on Dec. 18, 2015, the contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention The present invention relates to a display device for a vehicle. 
     2. Description of the Related Art 
     A meter device for a vehicle mounted in the vehicle has been known. The meter device for a vehicle includes a meter unit which has a vehicle information display area for displaying vehicle information such as a vehicle speed and an engine rotation speed. The vehicle further mounts an in-vehicle display used for a multimedia unit and a navigation system. 
     Mobile terminals such as a smartphone have been spread among people rapidly. The mobile terminal includes various kinds of functions such as a navigation function using GPS information, etc., an audio reproduction function for viewing a video image and listening to music and a browsing function for browsing webs provided on the internet. Such the mobile terminal is expected to be used in a vehicle as a matter of course. Thus, in order to improve convenience for an occupant of a vehicle, there has been also proposed a method in which the mobile terminal is connected to a device on the vehicle side and a display image of the mobile terminal is displayed on an in-vehicle display. 
     For example, JP-A-2012-124578 discloses an in-vehicle system which displays an image, being displayed on a display unit of a mobile phone, on a display unit of an in-vehicle device. Specifically, when the mobile phone is connected to the in-vehicle device, a control unit of the mobile phone reads image data representing an image being displayed on the display unit of the mobile phone from a memory and transfers the image data to the in-vehicle device via an interface. A control unit of the in-vehicle device receives the image data from the mobile phone via an interface, then performs an image processing using a memory and displays the image on the display unit of the in-vehicle device. 
     For example, JP-A-2012-111330 discloses a method of operating an icon on a mobile-phone side image displayed on a display unit of a vehicle in response to a switch operation of an operation unit (pointing device) provided at a center console of the vehicle. 
     In general, an operation with respect to a mobile terminal is performed by a touch operation on a display screen of the mobile terminal. Thus, even if the display screen of the mobile terminal is displayed on a display unit mounted on a vehicle, an operation of the display screen cannot be performed by an ordinary operation switch mounted on the vehicle. 
     SUMMARY OF THE INVENTION 
     Therefore, the invention, having been contrived bearing in mind the heretofore described circumstances, has for its object to provide a display device for a vehicle which can perform operations substantially same as respective operations to be performed on a mobile terminal, by using an operation unit on the vehicle allowing an occupant of the vehicle to perform switch operations, while displaying on the display device for the vehicle an image to be displayed on a mobile display unit of the mobile terminal. 
     In order to solve this problem, the invention provides a display device for a vehicle includes: a connection unit configured to connect to a mobile terminal to communicate with the mobile terminal, the mobile terminal having a mobile display unit being capable of reading operation information based on a touch position, a touch direction, a touch timing or a combination thereof of an operation element with respect to a screen of the mobile display unit when a touch operation of the operation element is performed to the screen; a display unit configured to display a mobile display image to be displayed on the mobile display unit in a state where the mobile terminal is connected to the connection unit; a control unit configured to control display of the display unit; and an operation unit including a direction switch for performing a direction operation and a decision switch for performing a decision operation, and configured to input an operation instruction according to the direction operation or the decision operation to the control unit, wherein the control unit converts the operation instruction input from the operation unit into an operation signal corresponding to a touch operation for the mobile terminal and outputs the operation signal to the mobile terminal. 
     For example, the operation unit is a steering switch arranged at a steering wheel of the vehicle. 
     For example, the operation unit further includes a mode switch for switching among operation modes, and the operation modes include: a cursor mode for moving a cursor, which is displayed on the display unit so as to be superimposed on the mobile display image displayed on the display unit, in accordance with the direction operation of the direction switch; and a scroll mode for moving the mobile display image displayed on the display unit in accordance with the direction operation of the direction switch. 
     For example, in a case where the direction switch is operated in the scroll mode, the mobile display image displayed on the display unit moves gradually during a predetermined time in accordance with the direction operation of the direction switch. 
     For example, the mobile display image displayed on the display unit moves gradually during a constant time after the direction switch is operated in accordance with the direction operation of the direction switch. 
     For example, the mobile display image displayed on the display unit moves gradually during a period where the direction switch is operated, in accordance with the direction operation of the direction switch. 
     According to the invention, operations substantially same as respective touch operations to be performed on a mobile terminal can be performed on the mobile terminal by using an operation unit which allows an occupant of the vehicle to perform switch operations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram schematically showing configuration of a meter device for a vehicle according to the first embodiment. 
         FIG. 2  is an explanatory diagram schematically showing configuration of a meter unit. 
         FIG. 3  is an explanatory diagram showing a display state of a meter display. 
         FIG. 4  is an explanatory diagram showing another display state of the meter display 
         FIG. 5  is an explanatory diagram for explaining a drawing processing performed by a graphic controller. 
         FIG. 6  is an explanatory diagram schematically showing configuration of an operation unit. 
         FIG. 7  is an explanatory diagram of an operation mode. 
         FIGS. 8A and 8B  are explanatory diagrams of a focus mode. 
         FIG. 9  is an explanatory diagram showing an operable range of a cursor. 
         FIG. 10  is an explanatory diagram showing a correspondence relation between touch operations, operation modes and operations with respect to the operation unit. 
         FIG. 11  is an explanatory diagram showing concept of a coordinate conversion processing. 
         FIG. 12  is an explanatory diagram showing a marker for a scroll mode. 
         FIG. 13  is a flowchart illustrating a control processing for achieving a flick operation or a swipe operation by the operation unit. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     First Embodiment 
       FIG. 1  is a block diagram schematically showing configuration of a meter device  1  for a vehicle according to the first embodiment. The vehicle meter device  1  mainly includes a meter unit (display unit)  10  and a control unit  50 . In this embodiment, although the meter unit  10  and the control unit  50  are constituted separately, these units may be constituted integrally. 
       FIG. 2  is an explanatory diagram schematically showing configuration of the meter unit  10 . The meter unit  10  is disposed, for example, at a dashboard in front of a driver&#39;s seat and displays vehicle information for an occupant of the vehicle. The vehicle information is information relating to the vehicle. In this embodiment, the vehicle information relates to information of a vehicle state. The vehicle state includes at least a vehicle speed and an engine rotation speed. In addition, the vehicle state includes a mileage, a shift position, direction indicators, time, various kinds of alarms, and so on. 
     The meter unit  10  includes a vehicle information display area Al for displaying the vehicle information. In the vehicle information display area AI, various kinds of meters, e.g., a speedometer  11  for displaying a vehicle seed, a tachometer  12  for displaying an engine rotation speed, and so on are arranged. 
     Each of the speedometer  11 , the tachometer  12 , a water temperature meter  13 , a fuel meter  14   a,    14   b,  direction indicators  15  and so on is an ordinary analog meter. Each of these meters is constituted of an arc-shaped scale  11   a,    12   a,    13   a  or  14   a  and an indicator  11   b,    12   b,    13   b  or  14   b  for indicating a required position on the scale. 
     In the vehicle information display area AI, a meter display  20  for displaying various kinds of information is further arranged. The meter display  20  displays time of a clock provided in the vehicle, an ambient temperature of the vehicle, the shift position, a travel distance, the various kinds of alarms, and other vehicle information. The meter display  20  further displays an image which is displayed on a mobile display unit  101  of a mobile terminal  100  described later, as the need arises. 
     In consideration of visibility from the driver&#39;s seat, the meter display  20  is disposed, for example, almost at the center of the vehicle information display area AI, that is, between the speedometer  11  and the tachometer  12 . A TFT-LCD (Thin Film Transistor Liquid Crystal Display: an example of an LCD) can be used as the meter display  20 . The meter display  20  has a screen size (almost 7 inches, for example) necessary for securing various kinds of display areas described later. The meter display  20  has a resolution substantially same as that of the mobile display unit  101  of the mobile terminal  100 . Alternatively, in view of reduction of an operation load and a cost, the meter display may have a resolution lower than that of the mobile display unit  101  of the mobile terminal  100 . 
     The control unit  50  controls display of the meter unit  10 . The control unit includes a meter controller (meter CPU: meter Central Processing Unit)  51  for controlling an entirety of the meter unit  10 , a graphic controller (GDC: Graphic Display Controller)  55  for controlling display of the meter display  20 , a 
     CAN (Controller Area Network) communication unit  52 , and a power supply unit (PWR)  60 . The meter controller  51  and the graphic controller  55  are connected to each other so as to be capable of communication mutually. 
     The meter controller  51  transmits predetermined control data to the graphic controller  55  so as to display the vehicle information via the meter display  20 . The graphic controller  55  performs a drawing processing in accordance with the control data. 
     The graphic controller  55  is mainly constituted of a microcomputer which includes a CPU, an ROM, an RAM and an I/O interface as main constituent elements. A memory  57  constituted of a semiconductor nonvolatile memory is connected to the graphic controller  55 . 
     The graphic controller  55  performs the drawing processing in accordance with the control data transmitted from the meter controller  51 . The graphic controller  55  outputs image data as a result of the drawing processing to the meter display  20 , thus displaying a required image on the meter display  20 . 
       FIG. 3  is an explanatory diagram showing a display state of the meter display  20 . In the meter display  20 , a time area  20   a  displays time information of the clock provided in the vehicle, other areas  20   b  to  20   f  display ambient temperature information of the vehicle, shift position information, sectional travel distance information, mileage information and an icon representing a display menu, respectively, and a vehicle information content area  20   g  displays contents of other vehicle information. For example, the vehicle information content area  20   g  graphically displays an instantaneous fuel consumption, an average fuel consumption, a boost pressure, and so on, each together with a predetermined scale. 
     The graphic controller  55  is connected to a communication interface  56  which connects the vehicle meter device  1  to the mobile terminal  100  as to be capable of communication. The communication interface  56  is, for example, a wire communication interface. For example, an USB (Universal Serial Bus) is used as the communication interface. Alternatively, a radio communication interface may be used as the communication interface  56 . For example, a near field radio communication such as Bluetooth (a registered trade mark) or a wireless LAN may be applied to the communication interface. 
     An example of the mobile terminal  100  is a smartphone. Alternatively, a mobile terminal such as a mobile phone or a PDA (Personal Digital Assistance) may be used as the mobile terminal. The mobile terminal  100  includes the mobile display unit  101  for displaying an image according to contents subjected to an information processing by the mobile terminal  100 . 
     The mobile display unit  101  has a function of reading operation information based on a touch position, a touch direction, a touch timing or a combination thereof of a finger with respect to a screen of the mobile display unit  101 . Specifically, the mobile display unit includes a touch panel allowing a touch operation by a user. 
     The touch operations are operations according to various kinds of touch modes such as a touch position, a touch direction and a touch timing of a finger (an operation element) with respect to a screen of the mobile display unit  101  (touch panel) when a touch operation of the finger is performed to the screen. The touch direction of the finger is defined as a direction of a touch locus of the finger with respect to the screen when the finger is touched to the screen. When the touch operation is performed, the mobile terminal  100  reads finger operation information of the touch operation, specifically, coordinate information of a position touched by a finger. Typical examples of the touch operation are a tap operation, a flick operation, a swipe operation, a pinch-in operation and a pinch-out operation. The tap operation is touching an optional position on the mobile display unit  101  by a fingertip. The flick operation is touching an optional position on the mobile display unit  101  by a fingertip and moving away the fingertip quickly therefrom. The swipe operation is touching an optional position on the mobile display unit  101  by a fingertip and sliding the fingertip therefrom. The pinch-out operation is sliding two fingers touched at respective optional positions on the mobile display unit  101  so as to spread a distance therebetween. The pinch-in operation is sliding two fingers touched at respective optional positions on the mobile display unit  101  so as to shorten a distance therebetween. The touch operations may be performed by an operation element such as a touch pen and a finger or fingers and so on. In the following explanation, the touch operations performed by the operation element are also contained in the touch operations performed by the finger or the fingers. 
     When a predetermined menu item (for example, “display of a mobile display screen” menu) is selected by an operation unit  70  after the mobile terminal  100  is connected to the communication interface  56  of the vehicle meter device  1 , mobile image data is input to the graphic controller  55  from the mobile terminal  100 . The mobile image data is image data representing a display image displayed on the mobile display unit  101  and is outputted from the mobile terminal  100  in response to a request from the graphic controller  55 . The mobile image data is generated through a predetermined processing performed by the mobile terminal  100 . That is, the mobile terminal performs an image processing on a display image (hereinafter referred to as “a mobile display image”) displayed on the mobile display unit  101  so as to cope with a resolution of the meter display  20  and a screen size of a mobile display image area  20   h.    
     When the mobile image data is input to the graphic controller  55  from the mobile terminal  100 , the graphic controller perfumes a drawing processing according to the mobile image data. The graphic controller  55  outputs required image data obtained by the drawing processing to the meter display  20 , thus displaying the mobile display image on the meter display  20 . 
       FIG. 4  is an explanatory diagram showing another display state of the meter display  20 . The meter display  20  displays the mobile display image as well as the vehicle information. In the meter display  20 , in place of the vehicle information content area  20   g  illustrated in  FIG. 3 , the mobile display image area  20   h  for displaying the mobile display image is set. In this manner, the meter display  20  simultaneously displays the vehicle information display area (an area including the display areas  20   a  to  20   f ) for displaying vehicle information and the mobile display image area  20   h  for displaying the mobile display image in a manner that the mobile display image area  20   h  is set separately from the vehicle information display area so as to be distinguished therefrom. 
     The meter display  20  also displays a cursor  20   i  which is movable on the display screen, displayed so as to match with display of the mobile display image, in correspondence to an operation instruction input from the operation unit  70  described later. The cursor  20   i  is not always displayed on the meter display  20  but displayed only when a cursor mode is set as an operation mode described later. 
     The mobile display image area  20   h  is not necessarily set to have the same size and layout as those of the vehicle information content area  20   g  but may employ an optional size and layout. However, the mobile display image area  20   h  is preferably set to have a size larger than a screen size of the mobile display unit  101  of the mobile terminal  100 . By doing so, an occupant of the vehicle can view the mobile display image by the mobile display image area  20   h  having a screen size larger that of the mobile display unit  101  of the mobile terminal  100 . Further, as the mobile display image area  20   h  has the larger size, an entirety of the mobile display image displayed on the mobile display unit  101  can be displayed in the mobile display image area without cutting out a part of the mobile display image. 
       FIG. 5  is an explanatory diagram for explaining the drawing processing performed by the graphic controller  55 . An image displayed on the meter display  20  is layered. The graphic controller  55  draws images of respective layers based on the control data outputted from the meter controller  51  and the mobile image data outputted from the mobile terminal  100 , then prepares image data formed by superimposing images of at least one layer and outputs the image data thus prepared to the meter display  20 . 
     In this embodiment, the number of the layers is four, and an image formed by superimposing images of four layers L 1  to L 4  from an uppermost layer to a lowermost layer is displayed on the mobile display image area  20   h.  The cursor  20   i  is drawn at the uppermost layer L 1 , the vehicle information is drawn at the second upper layer L 2 , the mobile display image is drawn at the third upper layer L 3 , and other information (for example, a photographed image in a case of connecting a camera) is drawn at the lowermost layer L 4 . In this manner, the graphic controller  55  provides the dedicated layer  3  for drawing the mobile display image, and draws the vehicle information at the layer  2  different from the layer  3 . Further, in this embodiment, the cursor  20   i  is drawn at the layer L 1  different from the layer  3  for drawing the mobile display image. 
     As illustrated in  FIG. 4 , in an image displayed on the meter display  20 , if there is an image at a portion of the upper layer, this image of the upper layer is displayed at this portion. In contrast, if there is no image at a portion of the upper layer, an image of the lower layer is displayed at this portion. That is, an image of a layer with an upper level is displayed with higher priority. Incidentally, in place of this display method in which an image of the lower layer is not displayed due to the presence of an image of the upper layer, another display method may be employed in which a transmissivity of the upper layer is set to a suitable value so that an image of the lower layer is translucently displayed. 
     As one feature of this embodiment, the graphic controller  55  limits a drawing range (movable range) of the cursor  20   i  within a drawing range of the mobile display image, that is, the mobile display image area  20   h.  In other words, control specification of the cursor  20   i  is set so that the cursor  20   i  is displayed only within the mobile display image area  20   h  and not displayed outside this area. 
     In a case of moving the cursor  20   i  from an outer edge (for example, a left-side outer edge) of the mobile display image area  20   h  or a position near this edge to an outer edge on the opposite side (for example, a right-side outer edge) or a position near this edge, the cursor  20   i  is required to be moved over almost the entire range of the mobile display image area  20   h.  In this case, as it takes a time to move the cursor  20   i  and further an occupant of the vehicle has to perform a required operation continuously, convenience of the device degrades. 
     In view of this, in a state where the cursor  20   i  locates at the outer edge (for example, the left-side outer edge) of the mobile display image area  20   h,  if an operation instruction for moving the cursor  20   i  outside this outer edge (for example, left direction) is input, the graphic controller  55  preferably performs a loop processing. This loop processing is a processing of displaying the cursor  20   i  at the outer edge (for example, the right-side outer edge) of the mobile display image area  20   h  locating in opposite to the previous outer edge. By doing so, the cursor  20   i  can be moved efficiently within the mobile display image area  20   h,  and hence usability of the device can be improved. 
     As another feature of this embodiment, the graphic controller  55  converts an operation instruction input from the operation unit  70  into an operation signal corresponding to the touch operation and outputs the operation signal to the mobile terminal  100 . In this respect, the operation signal after the conversion is equivalent to a simulated coordinate signal and corresponds to a coordinate signal recognized by the mobile terminal  100  when the touch operation is performed on the mobile display unit  101 . As a precondition of this processing, operations with respect to the operation unit  70  are associated with the touch operations in advance, respectively. The graphic controller  55  performs such the conversion processing, thereby enabling to perform operations substantially same as the respective touch operations, with respect to the mobile terminal  100  through the operation unit  70  for switch operations. 
     The operation method of the mobile terminal  100  using the operation unit  70  will be described later. 
       FIG. 6  is an explanatory diagram schematically showing configuration of the operation unit  70 . The operation unit  70  is connected to the graphic controller  55 . The operation unit  70  is used for inputting an operation instruction according to an operation performed by an occupant of the vehicle. The operation unit  70  is, for example, a steering switch (STRSW) provided at a steering wheel  2 . 
     The operation unit  70  includes four direction switches, that is, upper, lower, left and right direction switches  70   a,    70   b,    70   c  and  70   d,  a decision switch  70   e,  a mode switch  70   f,  and a back switch  70   g.  Each of these switches  70   a  to  70   g  is designed to allow a switch operation (for example, a press operation) by an occupant of the vehicle. 
     Each of the four direction switches  70   a,    70   b,    70   c  and  70   d  serves to input an operation instruction relating to a moving direction of the cursor  20   i  displayed in an overlapped manner with the mobile display image displayed in the mobile display image area  20   h,  and also to input an operation instruction relating to a moving direction of the mobile display image displayed in the mobile display image area  20   h.  The decision switch  70   e  serves to input an operation instruction relating to decision of an occupant of the vehicle. 
     The mode switch  70   f  serves to input an operation instruction relating to switching of the operation mode. As illustrated in  FIG. 7 , a menu mode, a cursor mode, a focus mode, a scroll mode, an audio mode, etc., are prepared as the operation modes. 
     The menu mode is the operation mode for operating a menu item for switching the display contents of the vehicle information content area  20   g  and the mobile display image area  20   h  and an operation subject of the mobile terminal  100 . 
     The cursor mode is the operation mode for moving the cursor  20   i  displayed in the mobile display image area  20   h  according to an operation of optional one of the four direction switches  70   a,    70   b,    70   c  and  70   d  so as to achieve the touch operation such as the tap operation, a double tap operation or a long tap operation. 
     As illustrated in  FIGS. 8A and 8B , the focus mode is the operation mode for moving a focus  20   k  displayed in the mobile display image area  20   h  according to an operation of optional one of the four direction switches  70   a,    70   b,    70   c  and  70   d.  For example, in this focus mode, based on application information obtained from the mobile terminal  100 , an application screen displaying a list or icon of the application is displayed in the mobile display image area  20   h  and the focus  20   k  is displayed in a superimposed manner. Then, the list, the icon or the like within the application screen is designated and operated according to an operation of the focus  20   k.    
     The scroll mode is the operation mode for moving the mobile display image displayed in the mobile display image area  20   h  according to an operation of optional one of the four direction switches  70   a,    70   b,    70   c  and  70   d  so as to achieve the touch operation such as the flip operation or the swipe operation. 
     The audio mode is the operation mode for reproducing music or video contained in the mobile terminal  100 . 
     Each of these modes other than the menu mode can be used only in a state where the mobile terminal  100  is connected to the communication interface  56 . The operation mode can be switched sequentially from the menu mode through the cursor mode, the focus mode and the audio mode each time the mode switch  70   f  is operated. 
     The back switch  70   g  serves to input an operation instruction for returning the mobile display image displayed in the mobile display image area  20   h  to an immediately preceding state. 
     According to the vehicle meter device  1  thus configured, in a state where the mobile terminal  100  is not connected to the communication interface  56  of the vehicle meter device  1 , information relating to the vehicle information is displayed entirely in the vehicle information display area Al containing the meter display  20 . 
     In this case, an occupant of the vehicle can switch the kind of the vehicle information to be displayed on the meter display  20  through the operation of the operation unit  70 . 
     Next, an operation method of the mobile terminal  100  using the operation unit  70  will be explained as to a state where the mobile display image is displayed in the mobile display image area  20   h.    
       FIG. 10  is an explanatory diagram showing a correspondence relation between the touch operations, the operation modes and the operations with respect to the operation unit  70 . For example, “tapping” as one of the touch operations corresponds to a single push operation of the decision switch  70   e  in the cursor mode. Similarly, “double tapping” as one of the touch operations corresponds to a double push operation of the decision switch  70   e  in the cursor mode. “Long tapping” as one of the touch operations corresponds to a long push operation of the decision switch  70   e  in the cursor mode. “Flicking” as one of the touch operations corresponds to a single push operation of one of the direction switches  70   a  to  70   d  in the scroll mode. “Swiping” as one of the touch operations corresponds to a long push operation of one of the direction switches  70   a  to  70   d  in the scroll mode. “Pinching in” as one of the touch operations corresponds to a single push operation of the decision switch  70   e  in the scroll mode. “Pinching out” as one of the touch operations corresponds to a long push operation of the decision switch  70   e  in the scroll mode. Such the correspondence relation is only one example, and other optional operations of the operation unit  70  may be associated with the touch operations. 
     Usually, the application utilizing the mobile terminal  100  is executed by tapping the application displayed on the mobile display unit  101 . An occupant of the vehicle can select and operate the application installed in the mobile terminal  100  by selecting the cursor mode as the operation mode. 
     Hereinafter, an operation method of the mobile terminal  100  utilizing the cursor mode will be explained. As illustrated in  FIG. 4 , if the cursor  20   i  is displayed in the mobile display image area  20   h  in response to the selection of the cursor mode, an occupant of the vehicle selectively operates the direction switches  70   a  to  70   d  to move the cursor  20   i,  thus superimposing the center position of the cursor  20   i  on the desired application displayed in the mobile display image. Then, an occupant of the vehicle performs the single push operation of the decision switch  70   e.    
     When the single push operation of the decision switch  70   e  is performed, the graphic controller  55  obtains a coordinate (center coordinate of the cursor  20   i ) where the center point  20   ia  of the cursor  20   i  locates, based on a two-dimensional coordinate set in the mobile display image area  20   h  in advance. As the coordinate system differs between the mobile display image area  20   h  and the mobile display unit  101 , the graphic controller  55  performs a coordinate conversion processing based on the center coordinate of the cursor  20   i.  According to this coordinate conversion processing, as illustrated in  FIG. 11 , a coordinate (hereinafter referred to as “a corresponding coordinate”)  101   a  on the mobile display unit  101  positionally corresponding to the center point  20   ia  of the cursor  20   i  is specified. Then, the graphic controller  55  transmits the simulated touch operation signal (coordinate signal) based on the specified corresponding coordinate  101   a  to the mobile terminal  100 . 
     In response to the reception of the simulated touch operation signal, the mobile terminal  100  recognizes that as if the tap operation is performed with respect to the corresponding coordinate  101   a  of the mobile display unit  101 . As a result, the mobile terminal  100  executes the application corresponding to the tapped position on the mobile display unit. 
     Such the processing relating to the tap operation is also performed in the similar manner as to each of the double tap operation and the long tap operation. 
     Next, a switching processing of the operation mode will be explained. Firstly when the mode switch  70   f  is operated, the graphic controller  55  determines whether the operation is a single push operation or a long push operation based on an on-time of the mode switch  70   f  (that is, a time period during which the switch  70   f  is pushed). 
     In a case of the single push of the mode switch  70   f,  the graphic controller  55  sequentially switches the operation mode from one to another among the four modes, that is, the menu, cursor, focus and audio modes in response to every single pushing (see  FIG. 7 ). 
     In a case of the long push of the mode switch  70   f,  the graphic controller  55  switches between the cursor mode and the scroll mode. As illustrated in  FIG. 7 , in response to the long push of the mode switch, the graphic controller can also switch between the focus mode and the scroll mode or between the audio mode and the scroll mode. 
     When the operation mode is switched to the scroll mode, the graphic controller  55  switches the cursor  20   i  displayed on the meter display  20  to a marker  20   j  for the scroll mode as illustrated in  FIG. 12 . Irrespective of the immediately preceding cursor position, a display position of the marker  20   j  is set so that a center coordinate of the marker  20   j  coincides with a center coordinate of the mobile display image area  20   h.  In the scroll mode, an image is shifted with reference to the position of the marker  20   j.  Thus, as the marker is disposed at the center of the mobile display image area initially, an image can be moved easily to an optional direction. 
     Next, an operation method utilizing the scroll mode will be explained. In a case of moving the mobile display image (for example, map information) displayed on the mobile display unit  101 , usually, the flick operation or the swipe operation is performed on the mobile display unit  101 . An occupant of the vehicle can move the mobile display image displayed in the mobile display image area  20   h,  utilizing the scroll mode. 
       FIG. 13  is a flowchart illustrating a control processing for achieving the flick operation or the swipe operation. Firstly, in step  30  (S 30 ), the graphic controller  55  determines whether or not the operation signal is input from one of the direction switches  70   a  to  70   d.  If one of the direction switches  70   a  to  70   d  is operated, an affirmative determination is made in step  30 , and the processing proceeds to step  31  (S 31 ). 
     In step  31 , the graphic controller  55  determines whether or not an on-time of the one of the direction switches  70   a  to  70   d,  that is, a time period during which the one of the direction switches  70   a  to  70   d  is pushed is equal to or shorter than a determination value n (msec). The determination value n is set so as to distinguish between the single push operation and the long push operation. 
     If the operation on the one of the direction switches  70   a  to  70   d  is the single pushing (flick operation), the on-time is equal to or shorter than the determination value n. Thus, an affirmative determination is made in step  31 , and the processing proceeds to step  32  (S 32 ). In contrast, if the operation on the one of the direction switches  70   a  to  70   d  is the long pushing (swipe operation), the on-time is longer than the determination value n. Thus, a negative determination is made in step  31 , and the processing proceeds to step  35  (S 35 ). 
     In step  32 , the graphic controller  55  transmits a simulated flick operation signal to the mobile terminal  100 . Specifically, firstly the graphic controller  55  specifies an objective coordinate. In a case of executing the processing of step  32  for the first time by operating one of the direction switches  70   a  to  70   d,  the center coordinate of the marker  20   j  in the mobile display image area  20   h  is used as the objective coordinate. In contrast, in the succeeding case, an objective coordinate updated by step  34  (S 34 ) described later is used as the objective coordinate. 
     Next, the graphic controller  55  performs the coordinate conversion processing based on the objective coordinate. According to the coordinate conversion processing, a coordinate (corresponding coordinate) on the mobile display unit  101  positionally corresponding to the objective coordinate of the mobile display image area  20   h  is specified. Then, the graphic controller  55  transmits the simulated flick operation signal (coordinate signal) based on the specified corresponding coordinate to the mobile terminal  100 . 
     In step  33  (S 33 ), the graphic controller  55  determines whether or not the objective coordinate reaches a predetermined end coordinate. The end coordinate is set according to a moving amount of an image caused by the flick operation. For example, the end coordinate can be set at a position corresponding to a half size of the mobile display image area  20   h.  For example, in a case of reproducing in a simulated manner the flick operation of quickly moving a finger to the left direction, a coordinate at the center of the left end side of the mobile display image area  20   h  corresponds to the end coordinate. Also, for example, in a case of reproducing in a simulated manner the flick operation of quickly moving a finger to the upper direction, a coordinate at the center of the upper end side of the mobile display image area  20   h  corresponds to the end coordinate. 
     When the objective coordinate reaches the end coordinate, an affirmative determination is made in step  33 , and the control processing terminates. In contrast, when the objective coordinate does not reach the end coordinate, a negative determination is made in step  33 , and the processing proceeds to step  34  (S 34 ). 
     In step  34 , the graphic controller  55  performs a coordinate update processing. In this coordinate update processing, the graphic controller  55  updates the objective coordinate to a position shifted from the current position by a predetermined amount according to the operation direction of one of the direction switches  70   a  to  70   d.  For example, when the left direction switch  70   c  is operated, the objective coordinate is updated to a position shifted to the left direction from the current position by the predetermined amount. The shift amount can be determined by an initial setting or a manual setting by an occupant of the vehicle. 
     When the processing from step  32  to step  34  is continued for a constant time, the simulated flick signal is input continuously to the mobile terminal  100 . Thus, the mobile terminal  100  obtains continuously-changing coordinate information like a case where the flick operation is performed on the mobile display unit  101 . As a result, the mobile terminal  100  recognizes that as if the flip operation is performed on the mobile display unit  101  according to the movement of the corresponding coordinate. Then, the mobile terminal  100  gradually shifts the coordinate of the image displayed at the center of the mobile display unit  101  to a direction opposite the flick operation direction. By doing so, the mobile display image gradually moves, on the mobile display unit  101  and in the mobile display image area  20   h,  in correspondence to the operation direction of the one of direction switches  70   a  to  70   d  during a constant time after the operation of the one of direction switches  70   a  to  70   d.  The general flick operation employs a display mode in which a moving speed of an image is not constant but changes with time. For example, the moving speed of an image is high at first and then becomes lower with time. In view of this, the shift amount of the coordinate of an image is not necessarily constant but may be changed with time. 
     In step  35 , the graphic controller  55  transmits a simulated swipe operation signal to the mobile terminal  100 . Specifically, firstly the graphic controller  55  specifies an objective coordinate. In a case of executing the processing of step  35  for the first time by operating one of the direction switches  70   a  to  70   d,  the center coordinate of the marker  20   j  in the mobile display image area  20   h  is used as the objective coordinate. In contrast, in the succeeding case, an objective coordinate updated by step  37  (S 37 ) described later is used as the objective coordinate. 
     Next, the graphic controller  55  performs the coordinate conversion processing based on the objective coordinate. According to the coordinate conversion processing, a coordinate (corresponding coordinate) on the mobile display unit  101  positionally corresponding to the objective coordinate of the mobile display image area  20   h  is specified. Then, the graphic controller  55  transmits the simulated swipe operation signal (coordinate signal) based on the specified corresponding coordinate to the mobile terminal  100 . 
     In step  36  (S 36 ), the graphic controller  55  determines whether or not the operation signal from the direction switches  70   a  to  70   d  terminates. When an operation of the one of direction switches  70   a  to  70   d  is stopped, the operation signal from the one of direction switches  70   a  to  70   d  terminates. Thus, an affirmative determination is made in step  36 , and the control processing terminates. In contrast, when an operation of the one of direction switches  70   a  to  70   d  is continued, a negative determination is made in step  36 , and the processing proceeds to step  37  (S 37 ). 
     In step  37 , the graphic controller  55  performs a coordinate update processing. In this coordinate update processing, the graphic controller  55  updates the objective coordinate to a position shifted from the current position by a predetermined amount according to the operation direction of one of the direction switches  70   a  to  70   d.  For example, when the left direction switch  70   c  is operated, the objective coordinate is updated to a position shifted to the left direction from the current position by the predetermined amount. The shift amount can be determined by an initial setting or a manual setting by an occupant of the vehicle. When the objective coordinate reaches the coordinate at the end of the mobile display image area  20   h,  the center coordinate of the mobile display image area  20   h  is set as the objective coordinate in the next coordinate update processing. Then, the coordinate update processing is repeated from this center coordinate. 
     When the processing from step  35  to step  37  is continued for an operation period of the one of direction switches  70   a  to  70   d,  the simulated swipe signal is input continuously to the mobile terminal  100 . Thus, the mobile terminal  100  obtains continuously-changing coordinate information like a case where the swipe operation is performed on the mobile display unit  101 . As a result, the mobile terminal  100  recognizes that as if the swipe operation is performed on the mobile display unit  101  according to the movement of the corresponding coordinate. Then, the mobile terminal  100  gradually shifts the coordinate of the image displayed at the center of the mobile display unit  101  to a direction opposite the swipe operation direction. By doing so, the mobile display image gradually moves, on the mobile display unit  101  and in the mobile display image area  20   h,  in correspondence to the operation direction of the one of direction switches  70   a  to  70   d  during a period where the one of direction switches  70   a  to  70   d  is operated. 
     In this manner, according to the embodiment, the vehicle meter device  1  includes the communication interface  56  which is connectable to the mobile terminal  100  having the mobile display unit  101  capable of performing the touch operation so that the communication interface can communicate with the mobile terminal; the meter display  20  (mobile display image area  20   h ) for displaying the mobile display image to be displayed on the mobile display unit  101  in a state where the mobile terminal  100  is connected to the communication interface  56 ; the control unit  50  for controlling display of the meter display  20 ; and the operation unit  70  which includes the direction switches  70   a  to  70   d  for performing the respective direction operations and the decision switch  70   e  for performing the decision operation and inputs the operation instruction according to the switch operation of an occupant of the vehicle to the control unit  50 . The control unit  50  converts the operation instruction input from the operation unit  70  into the operation signal corresponding to the touch operation and outputs the operation signal to the mobile terminal  100 . 
     According to this configuration, as the mobile display image is displayed at the part of the vehicle information display area Al of the meter unit  10 , an occupant of the vehicle can view the mobile display image via the meter unit  10 . In general, as the vehicle meter device  1  is mounted in a vehicle as a device for displaying the vehicle information, the vehicle meter device  1  can display an image of the mobile terminal  100  so long as the meter device mounts predetermined functions. Further, as the vehicle meter device  1  is disposed at a position excellent in visibility for an occupant of the vehicle, in particular, a driver, a moving amount of a line of sight is shorter as compared with a case of displaying on an in-vehicle display. Thus, visibility of the mobile display image can be improved. As a result, as it is not necessary for a driver to directly view the mobile terminal  100 , the driver can be suppressed from being disturbed in concentration on driving. 
     Some of display units on vehicle sides include touch panels utilized for multimedia units and navigation systems. In this case, the mobile terminal  100  may be operated by the touch panel. However, based on a position of a touch operation perfumed on the display unit (touch panel) on a vehicle side, it is necessary to specify a display object, thus operated, which is displayed on the mobile terminal. Thus, it is required to install a dedicated application common to both the vehicle and the mobile terminal and to make a control event associate between the vehicle and the mobile terminal. As a result, although the dedicated application can be used on the vehicle side, usual application installed in only the mobile terminal cannot be used on the vehicle side, disadvantageously. 
     In a case where the display unit on the vehicle side is not disposed at a position operable by an occupant of the vehicle, the occupant cannot perform a touch operation irrespective of presence or absence of a touch panel, disadvantageously. 
     The display object may be operated by a cursor or a focus interlocking with a touch operation of the operation unit. However, as described above, as it is necessary to specify a display object, having been operated, which is displayed on the mobile terminal, common dedicated application is required to be installed in each of the vehicle and the mobile terminal. 
     In this respect, according to the configuration of this embodiment, an occupant of the vehicle can perform an operation substantially same as the touch operation with respect to the mobile terminal  100  via the operation unit  70  which allows the switch operation by the occupant. In particular, according to this embodiment, the control unit converts an operation instruction input from the operation unit  70  into an operation signal corresponding to a touch operation, specifically, a simulated coordinate signal corresponding to the touch operation and outputs the simulated coordinate signal. Thus, the mobile terminal  100  recognizes via the simulated coordinate signal that as if the tap operation is performed on the mobile display unit  101 . As a result, as it is not necessary to specify a display object having been operated based on an operation position in the mobile display image area  20   h  on the vehicle side, common dedicated application is not required to be installed in each of the vehicle and the mobile terminal. In this manner, the application installed in the mobile terminal  100  can be operated freely. 
     In this embodiment, as the mobile display image is displayed in the vehicle meter device  1 , the touch operation cannot be performed directly on this image. However, according to this embodiment, as the mobile display image can be operated using the operation unit  70  allowing the switch operation, the display and operation of the mobile display image on the vehicle meter device  1  can be achieved. 
     In this embodiment, the operation unit  70  is a steering switch arranged at the steering wheel  2  of the vehicle. 
     According to this configuration, a driver can easily operate the operation unit  70 . 
     Further, in this embodiment, the operation unit  70  further includes the mode switch  70   f  for switching the operation mode. The operation modes include the cursor mode for moving the cursor  20   i,  disposed in a superimposed manner on the mobile display image displayed on the meter display  20 , according to an operation of optional one of the direction switches  70   a  to  70   d,  and the scroll mode for moving the mobile display image displayed on the meter display  20  according to an operation of optional one of the direction switches  70   a  to  70   d.    
     This configuration provides the mode for operating the cursor  20   i  used for selecting a display object and the mode for moving the mobile display image. These modes can be selected freely according to an operation of the mode switch  70   f.  Thus, variety of the operations can be achieved by using the operation unit  70  having a limited number of the switches. 
     In this embodiment, the operations of the switches  70   a  to  70   g  of the operation unit  70  are associated with the cursor mode and the scroll mode. However, the operations of the switches  70   a  to  70   g  of the operation unit  70  may be associated with the menu mode or the audio mode. For example, in the audio mode, “reproduction” of a medium may be performed in response to a single push operation of the right direction switch  70   d.    
     Although the vehicle meter device according to the embodiment of the invention is explained above, the invention is not limited to this embodiment but, of course, may be modified in various manners within a range of the invention. For example, the vehicle information within the meter display and the display mode and layout of the mobile display image may be set individually according to design of the meter unit. Further, in this embodiment, in a case of displaying the vehicle information, a part of the information is displayed using the analog meters. Alternatively, an entirety of the vehicle information display area may be constituted of a display so that display contents of each of the various kinds of meters and meter display is displayed using a graphic processing. 
     Although the embodiment is explained as to a case where the invention is applied to the vehicle meter device, the invention can be widely applied to a display device for a vehicle mounted in a vehicle, such as a display or headup display for a navigation system or multimedia. In this case, the vehicle information may contain vehicle travel information containing map information for route guidance and vehicle periphery and route guidance information, as well as information of the vehicle state. 
     Further, in this embodiment, although the switches are individually provided for the respective functions (direction, decision, mode and back), the invention is not limited thereto but only a single switch may be provided so as to be configured to cope with these functions.