Abstract:
An input device for inputting a command to an electronic system such as an on-board navigation system includes a microphone for inputting voice, a voice recognizer for analyzing the inputted voice and comparing it with data stored in a voice recognition dictionary, a touch panel displaying keys corresponding to the inputted voice and a controller for controlling operation of the input device. User&#39;s voice inputted from the microphone is fed into the voice recognizer to calculate a degree of coincidence with the data in the voice recognition dictionary. The keys corresponding to the inputted voice having a high degree of coincidence are displayed on the touch panel in an enlarged size. The enlarging rates may be determined according to the degree of coincidence. The user is able to finalize, easily and quickly, the keys constituting a command by touching the panel because candidate keys are enlarged.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based upon and claims benefit of priority of Japanese Patent Application No. 2007-314601 filed on Dec. 5, 2007, the content of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a device for inputting commands to an electronic system such as a navigation system. 
         [0004]    2. Description of Related Art 
         [0005]    An input device for inputting characters intended by a user is known hitherto. In this device, user&#39;s voice is recognized by a voice recognizer to specify characters intended by the user, and the recognized characters are inputted as a command to an electronic system such as a navigation system. However, there is a problem that the characters that are not correctly recognized by the voice recognizer are inputted as a command to the system. To avoid this problem, JP-A-2007-212658 proposes to display characters recognized by the voice recognizer in a highlighted manner and let a user to finalize the intended characters by touching the displayed characters. 
         [0006]    The input device proposed by JP-A-2007-212658 is used in a car navigation system which has a display panel having a limited display area. The characters shown in the display panel having a limited area are not easy to quickly specify and to touch them correctly even if the characters are shown in a highlighted manner. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an improved input device for inputting a command to a system quickly and correctly. 
         [0008]    The input device of the present invention is used for inputting commands to an electronic system such as a navigation system mounted on an automotive vehicle. The input device includes a microphone for inputting voice information such as a syllable or a word, a voice recognizer including a voice recognition dictionary, a display panel such as a liquid crystal display panel displaying a touch panel thereon, and a controller for controlling operation of the display panel and other components. The touch panel displays keys such as keys corresponding to 50 Japanese characters and other associated marks. 
         [0009]    Upon inputting voice information such as a syllable or a word from the microphone, the voice recognizer analyzes the inputted voice and compares it with data stored in the voice recognition dictionary. The controller calculates a degree of coincidence between the inputted voice and the dictionary data. The degree of coincidence represents likelihood of voice recognition. Keys displayed on the touch panel corresponding to the inputted voice having likelihood higher than a predetermined level are enlarged. The enlarging rates are determined according to the degree of coincidence. The user of the input device touches one or more keys displayed on the touch panel in an enlarged size, thereby to finalize the keys to be inputted as a command. 
         [0010]    Preferably, the enlarged keys are displayed not to overlap the other keys that are not enlarged. In the enlarging process, the keys may be gradually enlarged so that the user is able to more easily recognize the enlarged keys. The enlarged keys may be returned to an original size after a predetermined period has lapsed. In reducing the size of the keys, it may be gradually reduced. Alternatively, the keys having a lower degree of coincidence may be eliminated from the display so that the keys having a higher degree of coincidence are more clearly shown to the user. The voice recognizer may be put into operation upon initiation of inputting the voice information. 
         [0011]    According to the present invention, the user can easily and quickly finalize the correct keys for inputting a command by touching the touch panel since the candidate keys are enlarged. Other objects and features of the present invention will become more readily apparent from a better understanding of the preferred embodiment described below with reference to the following drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a block diagram showing a navigation system mounted on an automotive vehicle; 
           [0013]      FIG. 2  is a flowchart showing a process of inputting a syllable or a word to an input device; 
           [0014]      FIG. 3A  is a plan view showing a keyboard displayed on a display panel; 
           [0015]      FIG. 3B  is a plan view showing the same keyboard shown in  FIG. 3A , with certain characters shown in an enlarged size; 
           [0016]      FIG. 3C  is a plan view showing the same keyboard shown in  FIG. 3A , with a function key “History” shown in an enlarged size; and 
           [0017]      FIGS. 4A-4C  are drawings corresponding to  FIGS. 3A-3C , in which a keyboard showing a Japanese syllabary is replaced with a keyboard showing an alphabet. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0018]    A first embodiment of the present invention will be described with reference to accompanying drawings. First, an entire structure of a navigation system  1  mounted on an automotive vehicle will be briefly described with reference to  FIG. 1 . 
         [0019]    The navigation system  1  includes: a position detector  11  that detects a present position of a vehicle; a microphone  12  that outputs electric signal based on voices inputted by a user; a display panel  13  for displaying various information including maps; a speaker  14  for outputting sound information to the user; a touch panel  15  (including mechanical switches disposed around the panel) for inputting commands from the user; a talk switch  16  that is operated when the user inputs his/her voices to the speaker; a memory device  17  for storing map data and other information therein; and a controller  18 . The memory device  17  also stores a voice recognition dictionary  17   a.  The controller  18  that performs various processes according to signals from the position detector  11 , the microphone  12 , the touch panel  15 , the talk switch  16  and the memory device  17 , and controls the display panel  13 , the speaker  14  and memory device  17 . 
         [0020]    The position detector  11  includes: a GPS (Global Positioning System) receiver  11   a  that receives electromagnetic waves transmitted from GPS satellites through a GPS antenna and detects positions and directions of the vehicle; a gyroscope  11   b  for detecting an amount of rotation given to the vehicle; a distance sensor  11   c  for detecting a distance from an acceleration in a front to rear direction of the vehicle; and a magnetic sensor  11   d  for detecting a driving direction from a terrestrial magnetic field. Since these sensors  11   a - 11   d  include specific errors, these sensors are used while compensating respective errors one another. It is possible to eliminate some sensors, or to use a steering sensor or a wheel speed sensor in addition to or in place of some of the sensors. 
         [0021]    The navigation system  1  is operated according to commands inputted by a user through the microphone  12 . The display panel  13  is a color display panel, and it can be constituted by a liquid crystal display panel, a plasma display panel, a cathode ray tube or an organic electroluminescent panel. A present position of the vehicle detected by the position detector  11 , a map data fed from the memory device  17 , a calculated route to a destination, names of facilities, etc. are displayed on the display panel  13  in an overlapped manner. 
         [0022]    The touch panel  15  is integrally formed with the display panel  13  by laminating on each other. The touch panel  15  may be constituted by a pressure-sensitive panel, an electromagnetic induction panel, an electrostatic capacitance panel or a combination of these panels. The touch panel  15  may be formed also by devices other than those listed above. The talk switch  16  is disposed on a steering wheel of the vehicle so that a driver can easily operate it. The memory device  17  stores therein various data such as map data, so-called map-matching data for improving accuracy in determining a position of the vehicle, a navigation program to be performed by the controller  18 , and voice recognition dictionary  17   a.  The memory device  17  is composed of a magnetic memory such as a hard disc or the like, considering a large amount of data to be stored. 
         [0023]    The controller  18  is a known microcomputer including CPU, ROM, RAM, I/O, bus lines and other components. The controller  18  calculates a present position of the vehicle (a pair of a coordinate and a driving direction) based on the signals fed from the position detector  11  and the map data fed from the memory device  17  according to a program stored in the memory device  17 . The controller  18  displays a map around the present position on the display panel  13  together with a driving route to a destination. The destination is inputted by a driver&#39;s voice through the microphone  12 , and an optimum route to the destination is calculated in the controller  18 . The driver is guided to the destination by voice instructions through the speaker  14 . 
         [0024]    The controller  18  also includes a function to make a conversation with the driver and to receive driver&#39;s commands by voice. The controller  18  performs a process for inputting the user&#39;s commands by characters through the touch panel  15  and by voice through the microphone  12 . 
         [0025]    With reference to  FIG. 2 , a process of inputting a syllable or a word by voice will be described. The inputting process is started every time when the talk switch  16  is operated. Upon starting the process, an input display  20  shown in  FIG. 3A  is displayed on the display panel  13  at step S 10 . The input display  20  includes syllabary keys  21  having  50  Japanese characters and other marks, a portion  22  for displaying characters inputted and function keys  23 . Each one of the Japanese characters corresponds to a syllable, and a Japanese word is composed of one or plural syllables. The function keys  23  include an Enter key  23   a  for finalizing a character or a word to be inputted, a History key  23   b  for displaying again characters previously displayed. The syllabary keys  21  and the function keys  23  are collectively referred to as input keys. 
         [0026]    Then, at step S 20 , whether voice is inputted to the microphone  12  or not is determined. If not, the process awaits a voice input. If the voice is inputted, the process proceeds to step S 30  to perform voice recognition. In the voice recognition step, the voice inputted from the microphone  12  is analyzed and compared with data stored in the voice recognition dictionary  17   a.  A degree of coincidence between the inputted voice and the dictionary data is calculated. One or more candidates having the degree of coincidence higher than a predetermined level are selected from among the 50 characters. For example, characters having the degree of coincidence higher than 50% are selected as candidates. These candidates are considered to have a certain level of likelihood. In other words, the degree of coincidence corresponds to the likelihood in voice recognition. 
         [0027]    At step S 40 , whether the input is terminated or not is determined. This determination is done when a command word “end” is inputted and the word is recognized as the one having the highest degree of coincidence. If it is determined that the input is terminated, the process proceeds to the end. If not, the process proceeds to step S 50 , where enlarging rates of the input keys (the syllabary keys  21  or the function keys  23 ) corresponding to the candidates are calculated. For example, the enlarging rate of an input key corresponding to a candidate having the highest degree of coincidence is set to 300%. The enlarging rate of the second one is set to 200% and that of the third one is set to 150%. The enlarging rates are set according to the degree of coincidence. 
         [0028]    At step S 60 , a layout of the input keys is determined. More particularly, if three syllabary keys  21  ( 21   a ,  21   b  and  21   c ) are to be enlarged as shown in  FIG. 3B , the layout is arranged so that all the keys do not overlap on one another. In other words, a distance D 1  shown in  FIG. 3B  is made larger than predetermined distance. In the example shown in  FIG. 3B , the enlarging rate of key  21   a  is the highest, key  21   b  is the second, and key  21   c  is the third. If one of the function keys “History” is to be enlarged as shown in  FIG. 3C , the “History” key  23   b  is shown over other functions keys that are not enlarged. When the input keys are enlarged, they are displayed in a gradually enraging manner (animated manner). 
         [0029]    At step S 80 , whether input keys displayed on the touch panel  15  are touched or not is determined. If the input keys are touched, the touched input keys (syllabary keys  21  or function keys  23 ) are determined as the final input keys at step S 90 . Then, the process proceeds to step S 110 , where the input display  20  returns to an initial state. If the input keys are not touched at step S 80 , the process proceeds to step S 100 , where it is determined that a predetermined period has lapsed after the keys are enlarged. The process returns to step S 80  to await the lapse of the predetermined period. If it is determined that the predetermined period has lapsed at step S 100 , the process proceeds to step S 110 , where the input display  20  returns to the initial state. When the enlarged input keys are reduced to the initial size, the size is gradually reduced (animated). The process returns to step S 20  after the input display  20  is returned to the initial state to repeat the same process described above. 
         [0030]    As explained above, the voice inputted from the microphone  12  is subjected to the voice recognition, and the input keys corresponding to the voice recognized with high likelihood are enlarged on the touch panel  15 . The input keys are finalized by touching the enlarged keys on the touch panel  15 . 
         [0031]    The following advantages are attained in the embodiment described above. Since the keys having high likelihood are enlarged on the touch panel  15 , the user can easily and quickly touch desired input keys. The characters on the input keys are easily seen by the user by enlarging the input keys even if the characters are small in size in the initial state. Since the input keys are enlarged according to the degree of coincidence, the character having the highest likelihood is displayed with the largest size, and therefore the user can easily select the most desired character even when there are plural candidates. 
         [0032]    The input keys are finally confirmed by the user by touching the keys enlarged on the touch panel  15 . Since the keys are gradually enlarged, the user can further easily find the desired keys on the touch panel  15 . Since the size of the enlarged keys is reduced to the normal size after a predetermined period has lapsed, it is not required for the user to do some actions for returning the keys to the initial size. Since the size of the enlarged key is gradually reduced to the normal size, the user can easily recognize the key that is reduced to the normal size. 
         [0033]    Since the syllabary keys are displayed on the display panel  13  not to overlap one another when they are enlarged, other keys not enlarged are also visible so that the user can select desired keys from the other keys if the desired keys are not found among the enlarged keys. Since the enlarged function keys  23  are displayed in an overlapped manner on other function keys not enlarged, a process for avoiding the overlapping can be eliminated. Since the inputting process is started every time when the talk switch  16  is operated, commands can be inputted to the device such as a navigation system whenever such is desired by the user. 
         [0034]    The present invention is not limited to the embodiment described above, but it may be variously modified. For example, the input display  20  is not limited to the one having Japanese syllabary keys (shown in  FIGS. 3A ,  3 B and  3 C). It may be replaced with the input display having English alphabet keys (shown in  FIGS. 4A ,  4 B and  4 C). The inputting process can be similarly performed in this case, too. 
         [0035]    The input keys displayed on the display panel  13  may be selected not only by touching with a finger but also by a pointer. The shape of the enlarged input keys is not changed in the foregoing embodiment. It is possible to change their shape when enlarged. The enlarging rates are not limited to the example shown above. The enlarging rates can be arbitrarily selected as long as the candidate keys are distinguished from other keys. Further, the enlarging rates may be continuously changed according to the degree of coincidence. 
         [0036]    The minimum distance D 1  ( FIG. 3B ) is secured between an enlarged key and a non-enlarged key in the foregoing embodiment. It is also possible to arrange a flexible layout of the input keys to provide a minimum distance between neighboring keys by setting hypothetical springs among keys and end margins of the display panel under a simulation of dynamical mechanics. 
         [0037]    Though the syllabary keys  21  are enlarged not to overlap one another in the foregoing embodiment, it is also possible to display the enlarged keys to partially overlap with other keys, avoiding completely hiding other keys behind the enlarged keys. Only the candidate syllabary keys  21  may be displayed while erasing all of the other keys. In this case, the candidate keys may be either enlarged or not enlarged. The user can easily select desired keys from the candidate keys. 
         [0038]    Though the candidate keys having a higher degree of coincidence are enlarged in the foregoing embodiment, it is possible to reduce the size of non-candidate keys, instead. In this case, the size of the non-candidate keys may be gradually reduced in an animation-like manner. The reduced keys may be returned to the original size after a predetermined period (e.g., 5 seconds) has lapsed to eliminate any user&#39;s action for returning to the original size. Further, the reduced keys may be gradually returned to the original size in an animation-like manner. The rates of reducing the size of the keys  21  may be arbitrary set as long as the reduced keys are easily distinguished from other keys by the user. 
         [0039]    A combination of keys  21  which has a low possibility to be a candidate may be determined based on preliminary data or the degree of coincidence calculated at step S 30 . Though the inputting process is started by operating the talk switch  16  in the foregoing embodiment, it is possible to keep the inputting process active all the time during which power is supplied to the navigation system. In this manner, murmuring or conversation with another person can be inputted to the microphone  12  to select a candidate word from the murmuring or the conversation to display it in an enlarged manner on the display panel  13 . For example, a word “History” may be selected from an utterance “it could be found in History.” If the “History” is picked up, the function key  23   b  “History” is displayed in an enlarged manner. 
         [0040]    Though the input process is terminated when the word “end” is recognized at step S 40 , it is possible to terminate the inputting process when a predetermined period has lapsed with no voice inputted or when the talk switch  16  is operated again while the inputting process is being active. 
         [0041]    While the present invention has been shown and described with reference to the foregoing preferred embodiment, it will be apparent to those skilled in the art that changes in form and detail may be made therein without departing from the scope of the invention as defined in the appended claims.