Patent Publication Number: US-2020293118-A1

Title: Character input device, character input method, and character input program

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to Japanese Patent Application No. 2019-045469 filed on Mar. 13, 2019, the contents of which are incorporated herein by reference. 
     FIELD 
     The disclosure relates to a technique for inputting characters in a virtual space. 
     BACKGROUND 
     An input device described in Patent Literature 1 allows a touchpad operation in a virtual space. A user operates the input device with his or her digit to input characters in a virtual space or to operate, for example, an application. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2014-154074 
     SUMMARY 
     Technical Problem 
     However, the user operates the input device with the structure described in Patent Literature 1 while holding the device in his or her hand, and thus has a limitation in other operations. The user may thus have a lower sense of immersion in the virtual space. 
     One or more aspects are directed to a technique for enabling an efficient input operation without lowering the user&#39;s sense of immersion. 
     Solution to Problem 
     A character input device includes a display that displays a scene image in a virtual space with a virtual character input function, a starting character determination unit that identifies a starting position for the character input in the virtual character input function, an operation direction determination unit that detects a direction from the starting position, an operation detector that determines the character input in accordance with the direction, and a controller that outputs information indicating an operation of the character input to the display. 
     This structure enables the user to efficiently input characters without having a lower sense of immersion in the virtual space. 
     The operation direction determination unit in the character input device may be a touchpad. 
     This structure facilitates determination of the direction of a character input. 
     The operation direction determination unit in the character input device may be a cross-shaped key. 
     This structure allows reliable determination of the direction of a character input. 
     The display in the character input device may display the virtual space in a manner superimposed on a real space. 
     This structure is usable for augmented reality. 
     The display in the character input device may display a real space in a manner superimposed on the virtual space. 
     This structure is usable for mixed reality. 
     The display in the character input device may display the virtual space having a time axis in a manner superimposed on a real space. 
     This structure is usable for substitutional reality. 
     Advantageous Effects 
     One or more aspects enable an efficient input operation without lowering a user&#39;s sense of immersion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating a character input device according to a first embodiment. 
         FIGS. 2A and 2B  are schematic diagrams illustrating a character input device according to a first embodiment. 
         FIG. 3  is a flow diagram illustrating an operation of a character input device according to a first embodiment. 
         FIG. 4  is a schematic diagram illustrating a character input device according to a second embodiment. 
         FIG. 5  is a block diagram illustrating a character input device according to a third embodiment. 
         FIG. 6  is a schematic diagram illustrating a character input device according to a third embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments are now described with reference to the drawings. 
     Example Use 
     An example use is described first with reference to  FIG. 1 .  FIG. 1  is a block diagram of a character input device according to a first embodiment. A character input device  10  is, for example, a stick hand controller. The character input device  10  detects movement of a user&#39;s hand. 
     The character input device  10  includes a starting character determination unit  110 , an operation direction determination unit  120 , an operation detector  130 , and a controller  140 . 
     A user experiences the virtual space by wearing a virtual reality (VR) headset. The VR headset for experiencing the virtual space is in the form of goggles. The VR headset includes a gyroscope, an accelerometer, and a magnetometer. The VR headset is mounted on the head of the user, and detects forward and backward, right and left, and up and down movements of the head to project such movements on the x-, y-, and z-axes in the virtual space. 
     A virtual space  20  includes a display  200 . In other words, the display  200  is placed as a scene image appearing in the virtual space  20 , which is visible to the user wearing the VR headset. 
     The display  200  includes a virtual software keyboard that allows character input in the virtual space  20 . A string of characters is arranged on the software keyboard, for example, in the same format as a numeric keypad. When a character is input with the character input device  10  in the virtual space  20 , a display image based on the input character is output to the display  200 . The software keyboard is not limited to the same format as a numeric keypad described above, and may have any structure that allows input of a character string. 
     In an embodiment, the user identifies the display  200  in the virtual space  20  and inputs the Japanese hiragana character No. The user identifies, with the starting character determination unit  110  included in the character input device  10 , the hiragana N-column of the Japanese syllabary table. The operation detector  130  detects an input for the hiragana N-column. 
     The operation detector  130  outputs information indicating the input for the hiragana N-column to the controller  140 . The controller  140  outputs information indicating the input for the hiragana N-column to the display  200 . 
     The display  200  may display a flick input guide for the hiragana N-column. 
     When a key corresponding to a character to be input is selected, the flick input guide displays, as a guide, characters included in the same hiragana column as the character to be input. 
     More specifically, for example, the user selects the character Na. In response to this, the characters Na, Ni, Nu, Ne, and No appear in another area as a guide. In other words, the flick input guide allows the user to clearly recognize a character to be input. 
     The user selects the character No with the operation direction determination unit  120  included in the character input device  10 . 
     The operation detector  130  detects the character No selected by the user. The operation detector  130  outputs, to the controller  140 , information indicating that the character No is selected. The controller  140  outputs the character No to the display  200 . 
     In this manner, the user can input characters in the virtual space  20 . Additionally, the user can input characters with an easy operation. The user can use a familiar method for inputting characters, and thus does not have a lower sense of immersion. 
     Example Structure  1   
       FIG. 1  is a block diagram of a character input device according to a first embodiment.  FIGS. 2A and 2B  are schematic diagrams of the character input device according to a first embodiment.  FIG. 3  is a flowchart showing an operation of the character input device according to a first embodiment. 
     An example structure will be described in more detail with reference to  FIGS. 2A and 2B  based on the structure of the character input device  10  shown in  FIG. 1 . 
     As shown in  FIGS. 1 and 2A , a user  40  wears a virtual reality (VR) headset  30 . The user  40  can view the virtual space  20  through the VR headset  30 . The virtual space  20  includes the display  200 . 
     The user  40  holds the character input device  10 . As shown in  FIG. 2B , the character input device  10  includes the operation direction determination unit  120 . The operation direction determination unit  120  is, for example, a touchpad. More specifically, the touchpad includes a flat sensor. The touchpad is operable with a digit sliding on the sensor. 
     The user  40  identifies the display  200  in the virtual space  20 , and inputs the character No. The user  40  identifies the hiragana N-column. More specifically, the user  40  identifies the hiragana N-column on the display  200  in the virtual space  20  by, for example, pointing at the column with a laser pointer. For example, the position of the hiragana N-column may be identified with a gaze cursor included in the VR headset  30 . In response to this, the operation detector  130  detects an input for the hiragana N-column. 
     The operation detector  130  outputs information indicating the input for the hiragana N-column to the controller  140 . The controller  140  outputs information indicating the input for the hiragana N-column to the display  200 . 
     The user  40  operates the touchpad as the operation direction determination unit  120  with the same method as the flick input while pointing at the character Na on the display  200 . In this state, a flick input guide  220  displays characters included in the hiragana N-column. The user  40  performs a sliding operation downward from the character Na to select the character No. The character Na corresponds to a starting position or a starting point in an embodiment. 
     To input the character Na, an operation described below may be performed. The user  40  taps the operation direction determination unit  120  while pointing at the character Na. In response to this, the character Na is input. 
     The operation detector  130  detects the character No selected by the user  40 . The operation detector  130  outputs, to the controller  140 , information indicating that the character No is selected. The controller  140  outputs the character No to the display  200 . 
     A process performed by the character input device  10  will now be described with reference to the flowchart in  FIG. 3 . 
     The character input device  10  receives an operation performed by the user  40 , and activates the display  200  in the virtual space  20  (S 101 ). 
     The character input device  10  receives an operation performed by the user  40 , and identifies a starting character on the display  200  (S 102 ). 
     The operation detector  130  determines whether a starting character is identified (S 103 ). When the operation detector  130  determines that a starting character is identified (Yes in S 103 ), the character input device  10  receives an operation performed by the user  40  and selects an input character (S 104 ). The input character may be displayed by the flick input guide. 
     The operation detector  130  determines whether the input character is selected (S 105 ). When the operation detector  130  determines that the input character is selected (Yes in S 105 ), the controller  140  outputs the input character to the display  200  (S 106 ). 
     When determining that no starting character is identified in step S 103  (No in S 103 ), the processing in step S 102  is repeated. 
     When determining that no input character is selected in step S 106  (No in S 103 ), the processing in step S 104  is repeated. 
     In this manner, the user  40  can input characters in the virtual space  20 . Additionally, the user  40  can input characters with an easy operation. The user  40  can use a familiar flick input method for inputting characters, and thus does not have a lower sense of immersion. 
     Although the structure described above uses a touchpad as the operation direction determination unit  120 , the character input device  10  may have any structure that allows an input character to be selected by a sliding operation such as a flicking operation. 
     The character input device  10  may have any shape that does not eliminate the sense of immersion for the user. The operation direction determination unit  120  may also have any shape. 
     The structure described above uses the flick input guide  220  to input characters on the display  200 , and improves usability for the user  40  in inputting characters. However, the above structure may eliminate the flick input guide  220  when the flick input guide lowers the sense of immersion for the user  40 . 
     Example Structure  2   
     An operation for inputting a character will now be described in detail with reference to  FIG. 4 .  FIG. 4  is a schematic diagram of a character input device according to a second embodiment. 
     A second embodiment differs from a first embodiment in the shape of an operation detector. The other components and processes are the same as those in a first embodiment, and will not be described. 
     A character input device  10 A includes an operation direction determination unit  120 A. The operation direction determination unit  120 A is, for example, a cross-shaped key. 
     This structure allows the user to more easily determine the direction being identified. In other words, this structure reduces input errors in selecting characters to be input. 
     This structure also allows the user  40  to input characters in the virtual space  20 . Additionally, the user  40  can input characters with an easy operation. The user  40  can use a familiar method for inputting characters with a cross-shaped key, and thus does not have a lower sense of immersion. 
     Example Structure  3   
     An operation for inputting a character will now be described in detail with reference to  FIG. 5 .  FIG. 5  is a block diagram of a character input device according to a third embodiment.  FIG. 6  is a schematic diagram of the character input device according to a third embodiment. 
     A third embodiment differs from a first embodiment in including a transmissive display  200 A. The other components and processes are the same as those in a first embodiment, and will not be described. 
     A virtual space  20 A includes the transmissive display  200 A. More specifically, the transmissive display  200 A displays the virtual space  20 A in a manner superimposed on a real space. In other words, the virtual space  20 A is used in augmented reality (AR). 
     The transmissive display  200 A is included in a thin plate-like device having a camera function. The transmissive display  200 A is, for example, a liquid crystal display of, for example, a smartphone. 
     The user  40  captures an image of a real space  50  using the camera function. The captured image of the real space appears on the transmissive display  200 A. 
     The user  40  inputs the Japanese hiragana character No on the transmissive display  200 A. The user  40  identifies the hiragana N-column on the transmissive display  200 A. The operation detector  130  detects an input for the hiragana N-column. 
     The operation detector  130  outputs information indicating the input for the hiragana N-column to the controller  140 . The controller  140  outputs information indicating the input for the hiragana N-column to the transmissive display  200 A. 
     The transmissive display  200 A uses the flick input guide  220  to display characters included in the hiragana N-column. 
     The user  40  operates the touchpad as the operation direction determination unit  120  with the same method as the flick input to perform a sliding operation from the character Na to select the character No. In this case, the user  40  performs a sliding operation downward as viewed from the front of the character input device  10 . In response to this, the character No is selected. 
     The operation detector  130  detects the character No selected by the user  40 . The operation detector  130  outputs, to the controller  140 , information indicating that the character No is selected. The controller  140  outputs the character No to the transmissive display  200 A. 
     This structure allows the user  40  to input characters in AR. Additionally, the user  40  can input characters with an easy operation. The user  40  can use a familiar method for inputting characters, and thus does not have a lower sense of immersion. 
     AR may use either a vision-based technique or a markerless technique. 
     The structure in the above example is used in AR. However, the transmissive display  200 A can also be used in mixed reality (MR), in which the transmissive display  200 A displays the virtual space and the real space in a mixed manner, or specifically, the transmissive display  200 A displays the real space in a manner superimposed on the virtual space. 
     Also, the transmissive display  200 A can be used in a space in which the virtual space having a time axis is displayed in a manner superimposed on the real space. 
     Structures in embodiments may be expressed in the appendix below. 
     Appendix 
     A character input device ( 10 ), comprising: 
     a display ( 200 ) configured to display a scene image in a virtual space allowing a character input; 
     a starting character determination unit ( 110 ) configured to identify a starting position for the character input; 
     an operation direction determination unit ( 120 ) configured to detect a direction from the starting position; 
     an operation detector ( 130 ) configured to determine the character input in accordance with the direction; and 
     a controller ( 140 ) configured to output information indicating an operation of the character input to the display. 
     REFERENCE SIGNS LIST 
     
         
           10 ,  10 A character input device 
           20 ,  20 A virtual space 
           30  VR headset 
           40  user 
           50  real space 
           110  starting character determination unit 
           120 ,  120 A operation direction determination unit 
           130  operation detector 
           140  controller 
           200  display 
           200 A transmissive display 
           210  character string display area 
           220  flick input guide