Abstract:
A display device for a motor vehicle includes a display control for generating a first image signal, an image multiplexer for combining the first image signal with a second image signal and for outputting a mixed image signal, and a screen for representing an image depending on the mixed image signal.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a display device for a motor vehicle, the device including an instrument cluster, for example. 
     BACKGROUND INFORMATION 
     An instrument cluster having a rigid printed circuit board situated on the back of a base element is described in German Published Patent Application No. 199 43 571. This base element is partly covered on the front by a supporting body, which is connected in an articulated manner to the base element. A flexible printed circuit board extends over the front of the base element and the supporting body, enclosing a defined angle to an edge region of a connection area hinged to the rigid circuit board, which is connected to this printed circuit board by bow-type soldering, for example. 
     Described in German Published Patent Application No. 199 41 352 is an instrument cluster with a base element divided into display fields, which are aligned at different angles to each other. Situated on the front of the base element is an additional circuit board, which extends over several display fields. It is made up of rigid circuit board parts, which have flexible connection areas including conductor paths in the transitional region of the display fields. 
     An integrated instrument cluster for display of different measuring data in a motor vehicle is described in German Published Patent Application No. 198 19 822, which is equipped with analog and digital display instruments. The integrated instrument cluster includes a device to control the display instruments and to execute one or a plurality of additional functions of the vehicle central electronic system and vehicle power electronics, and at least one integrated security device for the system. 
     An instrument cluster for display of different measuring data in a motor vehicle is described in German Published Patent Application No. 198 19 821, which is equipped with analog and digital display instruments, in which mechanical, optical and electrical components of the display elements are mounted on a circuit support device, and the electronic control of the display instruments is implemented via an electronics module that can be mounted on the circuit support device. The circuit support device has a wiring film, which can be stretched between a rear cover and a front cover. 
     An instrument cluster for display of different measuring data in a motor vehicle is also described in German Published Patent Application No. 198 19 393, which is equipped with analog and digital display instruments, in which mechanical, optical and electrical components of the display elements are mounted on a support plate, and the electronic control of the display instruments is implemented via an electronics module that can be mounted on the support plate. However, a circuit support device to support the wiring of the electrical components is mounted on the support plate. 
     Another display device for a motor vehicle is European Published Patent Application No. 0 272 877, for example. 
     SUMMARY 
     Example embodiments of the present invention may provide a display device, e.g., one including an instrument cluster, for a motor vehicle, and which may be produced more inexpensively, for example. 
     A display device for a motor vehicle may include an instrument cluster, e.g., the display device having a display control to generate a first image signal, an image multiplexer to combine the first image signal with a second image signal and to output a mixed image signal (including at least one component of the first image signal and/or the second image signal), as well as a monitor to display an image as a function of the mixed image signal. The display control and the image multiplexer may be situated in a housing, e.g., in a housing to accommodate the monitor as well as an electromechanical display, for instance. 
     Using the image multiplexer, the first image signal may be able to be prioritized with respect to the second image signal. Using the image multiplexer, the first image signal may be prioritizable with respect to the second image signal so that the mixed image signal is formed such that an image corresponding to the second image signal is imaged on a region of the monitor only if the first image signal has no image component for this region. To this end, the monitor may be subdivided into segments, e.g., virtual segments. In this instance, the mixed image signal may be formed such that in one segment, e.g., a virtual segment, of the monitor, an image corresponding to the second image signal is imaged only if the first image signal has no image component for this segment, e.g., virtual segment. 
     The display device may include an image-input interface, such as a video interface, e.g., a DVI interface (digital video interface), or an RGB interface or an LVDS data interface for reading in the second image signal, etc. 
     The display device may include a control-signal interface such as a CAN-bus interface, to read in a control signal. 
     The first image signal may be able to be generated by the display control as a function of the control signal. 
     The display device may include an electromechanical display which may be able to be controlled by the display control as a function of the control signal. 
     A display device for a motor vehicle may include a cluster instrument, e.g., and a display control to generate a first image signal, as well as an image-input interface to read in a second image signal. 
     A motor vehicle may include a display device, e.g., one having the aforementioned features. The control signal may include the velocity of the motor vehicle and/or the rotational speed of an engine of the motor vehicle. 
     The control signal may include (among others) a temperature of an engine coolant, an oil pressure of the motor vehicle, a fill level of a tank of the motor vehicle, an instantaneous and/or average fuel consumption of the motor vehicle, a driven distance, an average driving speed, an ABS warning signal, a closing status of a door of the motor vehicle, a status of a parking brake, a status of a safety belt, a status of an airbag and/or a signal of a driver-assistance system, etc. 
     The motor vehicle may include an infotainment system having an image-output interface, the image-output interface being connected to the image-input interface via a data link. The second image signal may be able to be generated by the infotainment system. 
     It may be provided that the second image signal is able to include, or may include (depending on the operator&#39;s preference, for instance), an image signal to display information of a navigation system, a radio, a DVD player, a CD player, a telephone, a TV module and/or an air-condition system, etc. 
     The motor vehicle includes, or may include (depending on the operator&#39;s preferences), a rearview camera, which is connected to the image-input interface or the infotainment system via a data link, the second image signal including a video signal able to be generated by the rearview camera. 
     A control signal may include various control signal components transmitted in parallel, such as the speed of the motor vehicle, the engine speed of the motor vehicle, the temperature of the engine coolant, the oil pressure of the motor vehicle, the fill level of the tank of the motor vehicle, the instantaneous and/or average fuel consumption of the motor vehicle, the traveled distance, the average driving speed, the ABS warning signal, the closing status of a door of the motor vehicle, the status of the parking brake, the status of the safety belt, the status of the airbag and/or the signal of a driver-assistance system, etc. Different control signal components may also be transmitted in series, for instance according to the CAN bus protocol. 
     A motor vehicle may be, in particular, a land vehicle that may be used individually in road traffic. Motor vehicles are specifically not restricted to land vehicles having an internal combustion engine. 
     Further aspects and details of exemplary embodiments of the present invention are described in more detail below with reference to the appended Figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an internal view of a motor vehicle. 
         FIG. 2  is a basic representation of a motor vehicle having a display device. 
         FIG. 3  is a view of the display device illustrated in  FIG. 2 . 
         FIG. 4  is another view of the display device illustrated in  FIG. 2 . 
         FIG. 5  is another view of the display device illustrated in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is an interior view of a motor vehicle  1  having a display device  2  situated behind a steering wheel  3 .  FIG. 2  is a basic representation of motor vehicle  1  having display device  2 . Display device  2  has an LCD monitor  11  to display an image as a function of a mixed image signal BM, as well as an electromechanical display  13  having analog pointers, for instance, which is able to be controlled by a display control  28  as a function of a control signal ST able to be generated by, for instance, a control  24  of the motor vehicle and read in via a control-signal interface  22  such as a CAN bus interface. To this end, display control  28  generates a first display control signal ST 1 , which may be a voltage for moving an analog pointer to display the speed of the motor vehicle, or a voltage for moving an analog pointer to display the rotational speed of an engine of the motor vehicle. LCD monitor  11  is able to be turned on or off with the aid of a second control signal ST 2  able to be generated by display control  28 . 
     Control signal ST may include the speed of the motor vehicle, the rotational speed of the engine of the motor vehicle, a temperature of an engine coolant, an oil pressure of the motor vehicle, a fill level of a tank of the motor vehicle, an instantaneous and/or an average fuel consumption of the motor vehicle, a driven distance, an average travel speed, an ABS warning signal, a closing status of a door of the motor vehicle, a status of a parking brake, a status of a safety belt, a status of an airbag and/or a signal of a driver-assistance system, etc. 
     Furthermore, display device  2  includes a warning display  18  as visual alarm. It is possible to display warnings regarding an excessive temperature of the engine coolant, insufficient oil pressure of the motor vehicle, a defect of the ABS, an open door of the motor vehicle, a not fully deactivated parking brake, an unlatched safety belt, or a deactivated airbag, etc. The individual components of warning display  18  are able to be activated and deactivated with the aid of a third control signal ST 3  able to be generated by display control  28 . 
     Center axes  12  and  14  of LCD monitor  11  and electromechanical display  13  may be positioned at an angle α of 90° with respect to one another. Provided at an angle β of 45° from electromechanical display device  13  is a combiner  5 . This may be a planar, semitransparent mirror  15 , which is designed to transmit the image-forming light of LCD monitor  11 , so that an observer perceives the display image of LCD monitor  11  and warning display  18  directly. The image-forming light of electromechanical display  13  is reflected by semitransparent mirror  15 , so that it appears to an observer as a virtual image  16  superposed to monitor  11 . A diaphragm  17  may be provided above electromechanical display  13  by which portions of electromechanical display  13  are able to be covered as a function of a diaphragm-control signal STB. 
     Using display device  28 , a first image signal B 1  is able to be generated, for instance, to display the temperature of the engine coolant, the oil pressure of the motor vehicle, the fill level of the tank of the motor vehicle, the instantaneous and/or the average fuel consumption of the motor vehicle, the traveled distance, the average travel speed, the ABS warning signal, the closing status of the doors of the motor vehicle, the status of the parking brake and/or the displays of a driver-assistance system, etc., as a function of control signal ST. 
     Display device  2  also includes an image multiplexer  21  to combine first image signal B 1  with a second image signal B 2  able to read in via an image-input interface  23  designed as RGB interface, and to output mixed image signal BM. Display control  28  and image multiplexer  21  may be situated in a housing  20  to accommodate LCD monitor  11  and electromechanical display  13 . 
     Using multiplexer  21 , first image signal B 1  may be able to be prioritized with respect to second image signal B 2 . Using the image multiplexer, first image signal B 1  may be prioritizable with respect to second image signal B 2  so that mixed image signal BM is formed such that an image corresponding to second image signal B 2  is imaged on a region of LCD monitor  11  only if first image signal B 1  has no image component for this region. To this end, LCD monitor  11  may be subdivided into segments, for example, in particular virtual segments. In this instance, mixed image signal BM is formed such that in one segment, e.g., a virtual segment, of LCD monitor  11  an image corresponding to second image signal B 2  is imaged only if first image signal B 1  has no image component for this segment, e.g., virtual segment. 
     Furthermore, motor vehicle  1  has an infotainment system  25  by which second image signal B 2  is output via an image-output interface  29  which is connected to image-input interface  23  via a data link. It may be provided that second image signal B 2  includes, or may include (depending to an operator&#39;s wishes), for instance, an image signal to display information of, for instance, a navigation system assigned to infotainment system  25 , a radio assigned to, for instance, infotainment system  25 , a DVD player assigned to, for instance, infotainment system  25 , a CD player assigned to, for instance, infotainment system  25 , a telephone assigned to, for instance, infotainment system  25 , a TV module assigned to, for instance, infotainment system  25 , and/or a climate control system assigned to, for instance, infotainment system  25 . 
     The motor vehicle may include a rearview camera, which is connected to the image-input interface or the infotainment system via a data link, the second image signal including a video signal able to be generated by the rearview camera or able to include such (depending on the operator&#39;s preferences). 
       FIG. 3 ,  FIG. 4  and  FIG. 5  show an exemplary embodiment for a view of display device  2  illustrated in  FIG. 2 . Reference numerals  30 ,  31 ,  32 ,  33 ,  34 ,  35  and  36  denote individual components of warning indicator  18 , which are able to be turned on or off by third control signal ST 3  able to be generated by display control  28 . Reference numerals  42 ,  43 ,  52  and  53  denote (actual) pointers implemented on electromechanical display  13 . In the view illustrated in  FIG. 3 , pointers  52  and  53  are covered by diaphragm  17 , and in the view illustrated in  FIG. 4  and  FIG. 5 , pointers  42  and  43  are covered by diaphragm  17 . Reference numerals  40 ,  41 ,  50  and  51  denote scales assigned to pointers  42 ,  43 ,  52  and  53 . Scales  40 ,  41 ,  50  and  51  may be implemented as a component of electromechanical display  13 . The scales may be displayed on LCD monitor  11  as component of first image signal B 1 . 
     Reference numeral  45  denotes a segment in which a chronological time is shown in the views illustrated in  FIG. 3 ,  FIG. 4  and  FIG. 5 . Reference numeral  47  denotes a segment in which an odometer is displayed in the views illustrated in  FIG. 3 ,  FIG. 4  and  FIG. 5 , and reference numeral  48  denotes a segment in which a daily odometer is displayed in the views illustrated in  FIG. 3 ,  FIG. 4  and  FIG. 5 . Reference numeral  49  denotes a segment in which an average fuel consumption and a range are displayed in the view illustrated in  FIG. 3 . The time, the odometer, the daily odometer, the average fuel consumption, and the range are components of first image signal B 1 . 
     Reference numerals  44  and  46  in the view illustrated in  FIG. 3 , and reference numeral  54  in the view illustrated in  FIG. 4  denote navigation information, which is displayed on LCD monitor  11  and is part of second image signal B 2 . So that a display corresponding to the view illustrated in  FIG. 4  is allowed by image multiplexer  21 , first image signal B 1  is correspondingly limited by display control  28 . To this end, a data exchange between display control  28  and infotainment system  25  is provided via an interface  27 . For instance, infotainment system  25  is able to indicate to display control  28  which segments on LCD monitor  11  are to be utilized by infotainment system  25 . Display control  28  decides whether these segments (in first image signal B 1 ) are activated. In an analogous manner, this also applies to the display of an image  60 , assigned to second image signal B 2 , of a rearview camera  28  as illustrated in  FIG. 5 . 
     The elements in the figures are drawn with simplicity and clarity in mind, and not necessarily to an exact scale. Thus, for example, the orders of magnitude of some elements are exaggerated as compared to other elements in order to facilitate understanding. 
     LIST OF REFERENCE CHARACTER 
       1  motor vehicle 
       2  display device 
       3  steering wheel 
       11  LCD monitor 
       12 ,  14  center axis 
       13  electromechanical display 
       15  semitransparent mirror 
       16  virtual image 
       17  diaphragm 
       18  warning indicator 
       20  housing 
       21  image multiplexer 
       22  control-signal interface 
       23  image-input interface 
       24  control system 
       25  infotainment system 
       26  rearview camera 
       27  interface 
       28  display control 
       29  image-output interface 
       30 , 31 , 32 , 33 ,  34 ,  35 ,  36  components of a warning indicator 
       40 ,  41 ,  50 ,  51  scale 
       42 ,  43 ,  52 ,  53  pointer 
       44 ,  45 ,  47 ,  48 ,  49  segment 
       46 ,  54  navigation information 
       60  image 
     BM mixed image signal 
     B 1  first image signal 
     B 2  second image signal 
     ST control signal 
     STB diaphragm control signal 
     ST 1  first display control signal 
     ST 2  second display control signal 
     ST 13  third display control signal 
     α, β angle