Patent Publication Number: US-2017371510-A1

Title: Information processing apparatus, information processing system, and image forming apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2016-127754 filed Jun. 28, 2016. 
     BACKGROUND 
     (i) Technical Field 
     The present invention relates to an information processing apparatus, an information processing system, and an image forming apparatus. 
     (ii) Related Art 
     In some cases, information such as a recipient list or the like is displayed in the form of a display image in a display of an information processing apparatuses. When the display image of the information does not fit in the display, the information is typically viewed in the following method: a portion of the display image is displayed in the display, and the user scrolls the displayed display image. 
     SUMMARY 
     According to an aspect of the present invention, an information processing apparatus includes a display, an operating unit, and a movement controller. The display displays in a form of a display image a portion of information including plural items and moves the display image at a first speed by scrolling so as to display the plural items in a predetermined order. The operating unit accepts a movement instruction operation from a user for moving the display image. The movement controller performs control for reducing a movement speed to a speed lower than the first speed when a line of sight of the user toward the display image changes while the movement controller causes the display image to move. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiment of the present invention will be described in detail based on the following figures, wherein: 
         FIG. 1  illustrates an information processing system according to an exemplary embodiment; 
         FIG. 2  is the appearance of an image forming apparatus according to the present exemplary embodiment; 
         FIG. 3  illustrates an internal structure of the image forming apparatus according to the present exemplary embodiment; 
         FIG. 4  is an example of a display image displayed in the user interface; 
         FIG. 5  is a block diagram illustrating an example of a functional configuration of a control device; 
         FIG. 6  is a flowchart illustrating a first example of operations of the control device; 
         FIGS. 7A to 7D  illustrate examples of display images displayed in the user interface; 
         FIG. 8  is a flowchart illustrating a second example of the operations of the control device; and 
         FIGS. 9A and 9B  illustrate examples of display images displayed in the user interface. 
     
    
    
     DETAILED DESCRIPTION 
     An exemplary embodiment will be described in detail below with reference to the accompanying drawings. 
     Description of an Overall Structure of an Information Processing System 
       FIG. 1  illustrates an information processing system according to an exemplary embodiment. 
     As illustrated in  FIG. 1 , an information processing system S includes a detection device  500  and an image forming apparatus (information processing apparatus)  1 . The detection device  500  serves as an example of a detector that detects a line of sight of a user. The image forming apparatus  1  forms an image on a recording material. 
     Description of the Detection Device  500   
     The detection device  500  includes a camera  510  and a processing device  520 . The camera  510  is used to take an image of the user. The processing device  520  obtains the line of sight of the user in accordance with the image taken by the camera  510 . 
     The camera  510  includes, for example, an optical system and an image sensor. The optical system converges light incident thereupon. The image sensor is an imaging device that detects the light having been converged by the optical system. 
     The optical system includes a single lens or plural lenses combined with one another. Various types of aberrations are eliminated by a combination of the lenses, coatings provided on the surfaces of the lenses, and so forth. The image sensor includes imaging elements such as charge coupled devices (CCDs) or complementary metal oxide semiconductors (CMOSs) arranged therein. 
     The processing device  520  analyzes the image taken by the camera  510  and detects the line of sight of the user in accordance with the analysis of the image. Here, the line of sight of the user refers to, for example, information about what is a target watched by the user, and furthermore, includes, for example, information about the size of the pupil, information about whether or not the user intensely watches the target, and so forth. 
     The processing device  520  extracts, for example, parts of the user such as the face and the eye from the image taken by the camera  510  and detects the line of sight of the user in accordance with the orientation of the face, the position of the pupil in the eye, and the like. 
     Description of an Overall Structure of the Image Forming Apparatus  1   
       FIG. 2  is the appearance of the image forming apparatus  1  according to the present exemplary embodiment.  FIG. 3  is an internal structure of the image forming apparatus  1  according to the present exemplary embodiment. 
     The image forming apparatus  1  includes an image reading device  100  that reads an image on an original document and an image recording device  200  that records the image on the recording material (“recording material” is also representatively referred to as “sheet P” hereafter. Also, “sheet P” is described in the plural form “sheets P” where appropriate). Furthermore, the image forming apparatus  1  includes a user interface (UI)  300  that accepts operating input performed by the user and displays various types of information for the user. Furthermore, the image forming apparatus  1  includes a control device  400  that controls operations of the entirety of the image forming apparatus  1 . 
     The image reading device  100  is disposed on an upper portion of the image forming apparatus  1 . The image recording device  200  is disposed below the image reading device  100 . The control device  400  is disposed in the image recording device  200 . The user interface  300  is disposed in an upper central portion on the front side of the image processing apparatus  1 , that is, on the front side of a central portion of an image reading unit  110 , which will be described later, of the image reading device  100 . 
     First, the image reading device  100  is described. 
     The image reading device  100  includes the image reading unit  110  that reads the image of the original document and a document transport unit  120  that transports the original document to the image reading unit  110 . The document transport unit  120  is disposed in an upper portion of the image reading device  100 . The image reading unit  110  is disposed in a lower portion the image reading device  100 . 
     The document transport unit  120  includes a document loader  121  and a document output unit  122 . The document loader  121  contains the original document. The original document transported from the document loader  121  is output to the document output unit  122 . Thus, the original document is transported from the document loader  121  to the document output unit  122 . The document transport unit  120  is also referred to as an auto document feeder (ADF). 
     The image reading unit  110  includes a platen glass  111 , a light radiation unit  112 , a light guide unit  113 , and an imaging lens  114 . The light radiation unit  112  radiates light toward a target side (image side) of the original document. The light guide unit  113  guides light L radiated by the light radiation unit  112  toward the target side of the original document and reflected at the target side of the original document. The imaging lens  114  focuses an optical image of the light L guided by the light guide unit  113 . Furthermore, the image reading unit  110  includes a detection unit  115  and an image processing unit  116 . The detection unit  115  includes a photoelectric converter such as a CCD image sensor that photoelectrically converts the light L having been focused by the imaging lens  114 , so that the detection unit  115  detects the focused optical image. The image processing unit  116  is electrically connected to the detection unit  115 , so that an electric signal as image information obtained by the detection unit  115  is transmitted to the image processing unit  116 . 
     The image reading unit  110  reads an image of the original document transported by the document transport unit  120  and an image of the original document placed on the platen glass  111 . 
     Next, the image recording device  200  is described. 
     The image recording device  200  includes an image forming section  20 , a sheet feed unit  60 , a sheet output unit  70 , and an inversion transport unit  80 . The image forming section  20  forms an image on the sheet P. The sheet feed unit  60  feeds the sheet P to the image forming section  20 . The sheet output unit  70  outputs the sheet P on which the image has been formed by the image forming section  20 . The inversion transport unit  80  inverts the sheet P on one side of which the image has been formed by the image forming section  20  while transporting again the sheet P toward the image forming section  20 . 
     The image forming section  20  includes four image forming units  21 Y,  21 M,  21 C, and  21 K for yellow (Y), magenta (M), cyan (C), and black (K). The image forming units  21 Y,  21 M,  21 C, and  21 K are arranged parallel to one another and spaced from one another with a certain distance set therebetween. The image forming units  21  include respective photosensitive drums  22 , respective chargers  23 , and respective developing devices  24 . The chargers  23  uniformly charge the surfaces of the respective photosensitive drums  22 . The developing devices  24  each develop an electrostatic latent image formed by laser radiation performed by an optical system unit  50 , which will be described later, with toner of a corresponding one of predetermined color components so as to make visible the electrostatic latent image. Furthermore, the image forming section  20  is provided with toner cartridges  29 Y,  29 M,  29 C, and  29 K that supply toner of the colors to the developing devices  24  of the respective image forming units  21 Y,  21 M,  21 C, and  21 K. 
     The image forming section  20  includes the optical system unit  50  below the image forming units  21 Y,  21 M,  21 C, and  21 K. The optical system unit  50  radiates laser light toward the photosensitive drums  22  of the image forming units  21 Y,  21 M,  21 C, and  21 K. The optical system unit  50  includes a semiconductor laser (not illustrated) and a modulator (not illustrated). The optical system unit  50  also includes a polygon mirror (not illustrated), a window (not illustrated) and a frame (not illustrated). The polygon mirror deflects and scans the laser light emitted from the semiconductor laser. The window formed of glass allows the laser light to pass therethrough. The frame tightly encloses the elements of the optical system unit  50 . 
     Furthermore, the image forming section  20  includes an intermediate transfer unit  30 , a second transfer unit  40 , and a fixing device  45 . The intermediate transfer unit  30  performs multi-transfer, through which the toner images of the colors formed on the photosensitive drums  22  of the image forming units  21 Y,  21 M,  21 C, and  21 K are transferred onto an intermediate transfer belt  31 . The second transfer unit  40  transfers the toner images superposed on the intermediate transfer unit  30  onto the sheet P. The fixing device  45  fixes the toner images formed on the sheet P by applying heat and pressure. 
     The intermediate transfer unit  30  includes the intermediate transfer belt  31 , a drive roller  32 , and a tension roller  33 . The drive roller  32  drives the intermediate transfer belt  31 . The tension roller  33  applies a certain amount of, tension to the intermediate transfer belt  31 . The intermediate transfer unit  30  also includes first transfer rollers  34  and a backup roller  35 . Two or more (four according to the present exemplary embodiment) of the first transfer rollers  34  face the photosensitive drums  22  with the intermediate transfer belt  31  interposed therebetween and transfers the toner images formed on the photosensitive drums  22  onto the intermediate transfer belt  31 . The backup roller  35  faces a second transfer roller  41 , which will be described later, with the intermediate transfer belt  31  interposed therebetween. 
     The intermediate transfer belt  31  is looped over plural rotating members including, for example, the drive roller  32 , the tension roller  33 , the first transfer rollers  34 , the backup roller  35 , and a driven rollers  36 . The intermediate transfer belt  31  is rotated in an arrow direction at a predetermined speed by the drive roller  32  rotated by a drive motor (not illustrated). The intermediate transfer belt  31  is formed of, for example, rubber or resin. 
     The intermediate transfer unit  30  also includes a cleaner  37  that removes residual toner and the like existing on the intermediate transfer belt  31 . The cleaner  37  removes the residual toner, paper dust, and the like from the surface of the intermediate transfer belt  31  after the toner images have been transferred. 
     The second transfer unit  40  includes the second transfer roller  41  provided at a second transfer position. The second transfer roller  41  is pressed against the backup roller  35  with the intermediate transfer belt  31  interposed therebetween so as to transfer the images onto the sheet P through second transfer. The second transfer position is formed by the second transfer roller  41  and the backup roller  35  that faces the second transfer roller  41  with the intermediate transfer belt  31  interposed therebetween. At the second transfer position, the toner images having been transferred onto the intermediate transfer belt  31  are transferred onto the sheet P. 
     The fixing device  45  fixes onto the sheet P the images (toner images) having been transferred onto the sheet P through the second transfer performed by the intermediate transfer unit  30 . This fixing of the images is performed by utilizing heat and pressure with a heating fixing roller  46  and a pressure roller  47 . 
     The sheet feed unit  60  includes sheet containers  61 , feed rollers  62 , a transport path  63 , and transport rollers  64 ,  65 , and  66 . The sheet containers  61  contain the sheets P on which images are to be formed. The feed rollers  62  feed sheets P contained in the sheet containers  61 . The sheets P fed by the feed rollers  62  are transported through the transport path  63 . The transport rollers  64 ,  65 , and  66  are disposed along the transport path  63  so as to transport the sheets P fed by the feed rollers  62  to the second transfer position. The sheet feed unit  60  also includes a manual feed tray  67  that allows the sheets to be manually fed. The manual feed tray  67  is openable. Thus, the manual feed tray  67  is opened when in use so as to allow the sheets P to be set therein and closed when not in use.  FIG. 3  illustrates the manual feed tray  67  in a closed state. 
     The sheet output unit  70  includes a first placement tray  71  and a second placement tray  72 . The first placement tray  71  is provided above the image forming section  20  and allows the sheets P on which the images have been formed by the image forming section  20  to be placed therein. The second placement tray  72  is provided between the first placement tray  71  and the image reading device  100  and allows the sheets P on which the images have been formed by the image forming section  20  to be placed therein. 
     The sheet output unit  70  also includes a transport roller  75  and a switching gate  76 . The transport roller  75  is provided downstream of the fixing device  45  in a transport direction so as to transport each of the sheets P onto which the toner images have been fixed. The switching gate  76  is provided downstream of the transport roller  75  in the transport direction and switches the transport direction of the sheet P. The sheet output unit  70  also includes a first output roller  77  disposed downstream of the switching gate  76  in the transport direction. The first output roller  77  outputs to the first placement tray  71  the sheet P transported in the transport direction switched to one side (right side of  FIG. 3 ) by the switching gate  76 . The sheet output unit  70  also includes a transport roller  78  and a second output roller  79  disposed downstream of the switching gate  76  in the transport direction. The transport roller  78  transports the sheet P transported in the transport direction switched to the other side (upper side of  FIG. 3 ) by the switching gate  76 . The second output roller  79  outputs the sheet P transported by the transport roller  78  to the second placement tray  72 . 
     The inversion transport unit  80  includes an inversion transport path  81  beside the fixing device  45 . The sheet P is inverted by rotating the transport roller  78  in the opposite direction to the direction in which the transport roller  78  outputs the sheet P to the second placement tray  72  and being transported through the inversion transport path  81 . Plural transport rollers  82  are provided along the inversion transport path  81 . The sheet P transported by these transport rollers  82  are fed to the second transfer position again by the transport rollers  82 . 
     Furthermore, the image recording device  200  includes a device-body frame  11  and a device housing  12 . The device-body frame  11  directly or indirectly supports the image forming section  20 , the sheet feed unit  60 , the sheet output unit  70 , the inversion transport unit  80 , and the control device  400 . The device housing  12  is attached to the device-body frame  11  so as to form the outer surface of the image forming apparatus  1 . 
     The device-body frame  11  includes a reading-device support  13  on one lateral end side of the image forming apparatus  1 . The components such as the switching gate  76 , the first output roller  77 , the transport roller  78 , and the second output roller  79  are disposed in the reading-device support  13 . The reading-device support  13  extends in the up-down direction so as to support the image reading device  100 . The reading-device support  13  cooperates with a portion of the device-body frame  11  on the rear side for supporting the image reading device  100 . 
     Furthermore, the image recording device  200  includes a front covering  15  as part of the device housing  12 . The front covering  15  is provided on the front side of the image forming section  20  and openably attached to the device-body frame  11 . 
     The user is able to replace any of the intermediate transfer unit  30  and the toner cartridges  29 Y,  29 M,  29 C, and  29 K of the image forming section  20  with a new one by opening the front covering  15 . 
     The user interface  300  is, for example, a touch panel. With the touch panel used as the user interface  300 , various types of information such as image forming conditions of the image forming apparatus  1  are displayed in the touch panel. The user performs input operations for the image forming conditions and so forth by touching the touch panel. That is, the user interface  300  functions as a display that displays information relating to the image forming apparatus  1  in which the user interface  300  is included and also functions as an operating unit that accepts an operation performed by the user. The user interface  300  is not necessarily a touch panel. The functions of the display and the functions of the operating unit may be separated. That is, the user interface  300  may include a display and an operating unit separated from each other. In this case, the display includes a liquid crystal display or the like so as to display information relating to the image forming apparatus  1 , and the operating unit includes physical buttons or the like so as to accept the operation performed by the user. 
     Description of the Operations of the Image Forming Apparatus  1   
     The image forming apparatus  1  having the above-described structure operates as follows. 
     For example, the user is able to copy an original document by using the image forming apparatus  1 . That is, the original document is able to be copied by forming an image on the sheet P with the image recording device  200  in accordance with image data of the original document read by the image reading device  100 . Furthermore, the user is able to perform printing by transmitting a print job to the image forming apparatus  1  from a personal computer (PC) or the like (not illustrated) connected to a line of communication. That is, the printing is able to be performed by receiving the print job through the line of communication and forming an image on the sheet P with the image recording device  200  in accordance with image data included in the print job. Furthermore, facsimile communication is usable for the user. That is, image data of an original document read by the image reading device  100  is able to be transmitted through the line of communication. The user is also able to save image data of an original document. That is, the image data of the original document is able to be saved in the image forming apparatus  1  or a PC connected to the line of communication. 
     Here, operations of the image forming apparatus  1  are described in detail with an example in which the user copies an original or performs printing. 
     An image of the original document read by the image reading device  100  and image data received from the PC or the like are subjected to predetermined image processing. The image data on which the image processing has been performed is converted into colorant gradation data of the four colors, that is, yellow (Y), magenta (M), cyan (C), and black (K) and output to the optical system unit  50 . 
     In the optical unit  50 , the laser light emitted from the semiconductor laser (not illustrated) in accordance with the received color gradation data is directed to the polygon mirror through an f-O lens (not illustrated). With the polygon mirror, the laser light incident thereupon is modulated in accordance with the gradation data of the colors, deflected and scanned, and radiated to the photosensitive drums  22  of the image forming units  21 Y,  21 M,  21 C, and  21 K through an imaging lens (not illustrated) and plural mirrors (not illustrated). 
     The surfaces of the photosensitive drums  22  of the image forming units  21 Y,  21 M,  21 C, and  21 K having been charged by the chargers  23  are exposed to and scanned by the laser light, thereby electrostatic latent images are formed. The electrostatic latent images having been formed are developed into toner images of yellow (Y), magenta (M), cyan (C), and black (K) colors by the respective image forming units  21 Y,  21 M,  21 C, and  21 K. The toner images formed on the photosensitive drums  22  of the image forming units  21 Y,  21 M,  21 C, and  21 K are transferred onto the intermediate transfer belt  31  serving as an intermediate transfer body through multi-transfer. 
     Meanwhile, in the sheet feed unit  60 , the sheet P contained in one of the sheet containers  61  is picked up by rotating a corresponding one of the feed rollers  62  at timing adjusted to timing of image formation. The picked up sheet P is transported through the transport path  63  by the transport rollers  64  and  65 . After that, the transport roller  66  is rotated at timing adjusted to movement timing of the intermediate transfer belt  31  on which the toner images have been formed, thereby transporting the sheet P to the second transfer position formed by the backup roller  35  and the second transfer roller  41 . At the second transfer position, the toner images of four colors superposed on one another are transferred in the sub-scanning direction by using a pressure contact force and a predetermined electric field onto the sheet P being transported upward from below. The sheet P onto which the toner images of the colors have been transferred is subjected to a fixing process of heat and pressure performed by the fixing device  45  and then output and placed in the first placement tray  71  or the second placement tray  72 . 
     When duplex printing is requested, the sheet P on one side of which the images have been formed is transported by the inversion transport unit  80  so as to be inverted, and the sheet P is fed again to the second transfer position. At the second transfer position, the toner images are transferred onto the other side of the sheet P, and the transferred images are fixed by the fixing device  45 . After that, the sheet P on both the sides of which the toner images have been formed is output and placed in the first placement tray  71  or the second placement tray  72 . 
     The user interface  300  operates as follows. 
       FIG. 4  is an example of a display image displayed in the user interface  300 . 
     As has been described, information displayed in the user interface  300  is information relating to the image forming apparatus  1  in which the user interface  300  is included. Specifically, when the user copies an original document or performs a printing operation, image forming conditions such as the size of the sheet P to be used, simplex printing/duplex printing, and so forth are displayed in the user interface  300 . When the user performs a facsimile operation, a list that includes abbreviated numbers and names of recipients and so forth of the facsimile is displayed in the user interface  300 . Furthermore, when the user saves image data having been read, a list of destinations for saving the image data is displayed in the user interface  300 . 
     In the example of, for example,  FIG. 4 , a list of recipients of facsimile is displayed as a “Recipient List” in the user interface  300 . In this case, the abbreviated number and the name of each of the recipients are combined as a single item, and plural items are arranged in the up-down direction of the user interface  300  of, for example,  FIG. 4 . 
     In this state, a portion of information including plural items is displayed as a display image in the user interface  300 . That is, when there are many items, it is impossible to display all the items at once in the user interface  300 . Accordingly, among all the items, some of the items are displayed and other items are to be displayed in a predetermined order by being moved (transitioned) due to scrolling of the display image. In this case, scrolling is performed in the up-down direction of the user interface  300  of, for example,  FIG. 4 . The scrolling may be performed by moving the display image by a predetermined number of pixels or by defining the display image displayed at a time as a single page and sequentially changing pages from one page to another page. 
     The user interface  300  starts the scrolling upon reception of a movement instruction operation from the user for moving the display image. 
     Specifically, when the user interface  300  is a touch panel, the movement instruction operation is an operation in which the user swipes the touch panel. The movement instruction operation is not limited to this. For example, the movement instruction operation may be, for example, as follows: the user performs an operation such as touching or dragging a scroll bar that is displayed in the touch panel. Furthermore, when the user interface  300  includes a liquid crystal display and physical buttons separated from each other, the movement instruction operation may be an operation in which the user presses down a physical button to which a function of scrolling the display image is assigned. 
     The user interface  300  stops the scrolling upon reception of a stop instruction operation from the user for stopping the movement of the display image. 
     Specifically, when the user interface  300  is a touch panel, the stop instruction operation is an operation in which the user touches the touch panel. When the scroll bar is displayed in the touch panel, the stop instruction operation may be as follows: the user moves away from the touch panel his or her finger used to, for example, touch or drag the touch panel. Furthermore, when the user interface  300  includes a liquid crystal display and physical buttons separated from each other, the stop instruction operation may be an operation in which the user moves away his or her finger from a physical button to which a function of scrolling the display image is assigned. 
     However, when the number of the items further increases, the user may be required to scroll through more pages to reach his or her target item by scrolling. Accordingly, in addition to an increase in time, the user&#39;s attention may be distracted, and the user may miss the target item even when the target item is displayed and the user may continue scrolling. 
     Such a situation may be suppressed by controlling the speed at which the display image displayed in the user interface  300  is scrolled with the control device  400  as follows according to the present exemplary embodiment. Although it will be described in detail later, the control device  400  functions as a movement controller that controls the speed at which the display image is moved by scrolling. 
     Description of the Control Device  400   
       FIG. 5  is a block diagram illustrating an example of a functional configuration of the control device  400 . It is noted that, in  FIG. 5 , functions relating to the present exemplary embodiment are selected and illustrated out of various functions of the control device  400 . 
     As illustrated in  FIG. 5 , the control device  400  according to the present exemplary embodiment includes a display item determination unit  401 , an instruction operation determination unit  402 , a movement speed determination unit  403 , a line-of-sight determination unit  404 , and a display control unit  405 . The display item determination unit  401  determines the items to be displayed in the user interface  300 . The instruction operation determination unit  402  determines whether or not the movement instruction operation is performed and whether or not the stop instruction operation is performed. The movement speed determination unit  403  determines the movement speed of the scrolling. The line-of-sight determination unit  404  determines the line of sight of the user. The display control unit  405  controls the display image displayed in the user interface  300 . 
     The display item determination unit  401  determines the items to be displayed in the user interface  300  in accordance with the operation of the image forming apparatus  1 . Here, a case is described in which the user selects to perform a facsimile operation using the image forming apparatus  1  and the items such as items of  FIG. 4  are determined. 
     The instruction operation determination unit  402  determines whether or not the user inputs the movement instruction operation in accordance with information about the operation performed on the user interface  300  by the user. In this case, the instruction operation determination unit  402  determines, for example, whether or not the user swipes the touch panel. Alternatively, the instruction operation determination unit  402  determines, for example, whether or not the user presses down a physical buttons to which the function to perform scrolling of the display image is assigned. 
     The instruction operation determination unit  402  also determines whether or not the user inputs the stop instruction operation in accordance with information about the operation performed on the user interface  300  by the user. In this case, the instruction operation determination unit  402  determines, for example, whether or not the user moves away his or her finger from the touch panel. Alternatively, the instruction operation determination unit  402  determines, for example, whether or not the user releases the pressing down of the physical button to which the function to perform scrolling of the display image is assigned. 
     The movement speed determination unit  403  determines the scrolling speed when the plural items are moved by scrolling in the user interface  300 . 
     The line-of-sight determination unit  404  obtains information about the line of sight of the user detected by the detection device  500  (see  FIG. 1 ). Thus, the line-of-sight determination unit  404  determines what position is watched by the user. 
     The display control unit  405  performs control for displaying in the user interface  300  the items determined by the display item determination unit  401 . Furthermore, if the user inputs the movement instruction operation, the display control unit  405  performs control for scrolling the display image at the speed determined by the movement speed determination unit  403 . If the user input the stop instruction operation, the display control unit  405  performs control for stopping the scrolling of the display image. Actually, the display control unit  405  generates at a predetermined time interval display image data of the display image to be displayed in the user interface  300  and sequentially outputs the display image data to the user interface  300 . 
     Description of Operations of the Control Device  400  First Example 
     Next, a first example of operations of the control device  400  is described. 
       FIG. 6  is a flowchart illustrating the first example of the operations of the control device  400 .  FIGS. 7A to 7D  illustrate examples of display images displayed in the user interface  300 . In  FIGS. 7A to 7D , solid arrows indicate scrolling directions and dotted arrows indicate the line of sight of the user. 
     First, the display item determination unit  401  determines the items to be displayed in the user interface  300  (step S 101 ). 
     At this time, the display image of, for example,  FIG. 7A  is displayed in the user interface  300 . Here, what is illustrated in  FIG. 7A  is similar to or the same as what is illustrated in  FIG. 4 . 
     Next, the instruction operation determination unit  402  determines whether or not the user interface  300  has accepted the movement instruction operation from the user (step S 102 ). 
     If the user interface  300  has not been accepted the movement instruction operation (“NO” in step S 102 ), processing returns to step S 101 . In contrast, if the user interface  300  has accepted the movement instruction operation (“YES” in step S 102 ), the movement speed determination unit  403  selects a standard speed (first speed) and sets the standard speed as the movement speed (step S 103 ). The display control unit  405  performs control so as to cause the items to be sequentially displayed by the user interface  300  while causing the display image to move by scrolling at the standard speed (first speed) (step S 104 ). 
     At this time, the display image of  FIG. 7B  being moved by scrolling is displayed in the user interface  300 . 
     While the display image is being moved by scrolling, the instruction operation determination unit  402  determines whether or not the user interface  300  has accepted the stop instruction operation as the movement instruction operation from the user (step S 105 ). 
     If the user interface  300  has accepted the stop instruction operation (“YES” in step S 105 ), the display control unit  405  performs control for stopping the movement by scrolling (step S 106 ). 
     In contrast, if the user interface  300  has not been accepted the stop instruction operation (“NO” in step S 105 ), the processing advances to the next step, that is, step S 107 . 
     Next, the line-of-sight determination unit  404  obtains information about the line of sight of the user detected by the detection device  500  (step S 107 ). Furthermore, the line-of-sight determination unit  404  determines the position watched by the user (step S 108 ). 
     Furthermore, the line-of-sight determination unit  404  determines whether or not the user watches the user interface  300 , and further, whether or not this line of sight of the user has been changed (step S 109 ). Here, the change in the line of sight is not limited to a change in the position watched by the user. For example, an enlargement of the pupil, a sudden change of the eyepoint, intensive watching, and the like may be processed as the change in the line of sight. 
     If the line of sight of the user toward the user interface  300  has not been changed (“NO” in step S 109 ), the processing returns to step S 105 . 
     In contrast, if the line of sight of the user toward the user interface  300  has been changed (“YES” in step S 109 ), the display control unit  405  performs control for positioning the item corresponding to the line of sight of the user (the item watched by the user) at a position of a central portion in the scrolling direction of the user interface  300  (in this case, the up-down direction of  FIGS. 7A to 7D ) and for stopping the movement by scrolling (step S 110 ). 
     Assuming that the line of sight of the user changes in the display image of  FIG. 7C , and the user watches the item of “HIT Corporation” indicated by the head of the dotted arrow. In this case, in the user interface  300  as illustrated in  FIG. 7D , the item corresponding to the line of sight of the user (the item “HIT Corporation” watched by the user) is returned so as to be positioned in the central portion in the up-down direction of  FIGS. 7A to 7D , and the scrolling is stopped. 
     Furthermore, after the movement of the display image has been stopped, the instruction operation determination unit  402  determines whether or not the user interface  300  has further accepted the movement instruction operation from the user (step S 111 ). 
     If the user interface  300  has not been accepted the movement instruction operation (“NO” in step S 111 ), the processing ends. 
     In contrast, if the user interface  300  has further accepted the movement instruction operation from the user (“YES” in step S 111 ), the movement speed determination unit  403  selects a high speed (second speed) that is higher than the standard speed (first speed) and sets the high speed as the movement speed (step S 112 ). The display control unit  405  performs control for a movement at the high speed (second speed) that is higher than the standard speed (first speed) to the display image having been displayed when the line of sight of the user toward the display image changed (step S 113 ). After scrolling to the display image displayed when the line of sight of the user changed, the processing returns to step S 103 . That is, the display control unit  405  continues to cause the display image to move by scrolling with the movement speed returned to the standard speed (first speed). 
     According to the first example, the control device  400  performs control for reducing (in this case, stopping) the movement speed to a speed lower than the standard speed (first speed) when the line of sight of the user toward the display image changes while causing the display image to move. With this control, while the display image is being moved by scrolling, the display image is stopped at a position of an item of interest to the user. Thus, the user may easily find his or her target item. Furthermore, when the items that are displayed while the display image is stopped do not include the item that the user tries to find, the movement by scrolling is able to be restarted by performing again the movement instruction operation by the user. At this time, the movement to the display image displayed when the line of sight of the user changed is performed at the high speed (second speed). This may reduce time taken for the user to find the target item. 
     Second Example 
     Next, a second example of operations of the control device  400  is described. 
       FIG. 8  is a flowchart illustrating the second example of the operations of the control device  400 .  FIGS. 9A and 9B  illustrate examples of display images displayed in the user interface  300 . In  FIGS. 9A and 9B , solid arrows indicate scrolling directions and dotted arrows indicate the line of sight of the user. 
     Processing from step S 201  to step S 209  of  FIG. 8  is the same as or similar to the processing from step S 101  to step S 109 . Thus, description of the processing from step S 201  to step S 209  is omitted. 
     In step S 209 , if the line of sight of the user toward the user interface  300  has changed (“YES” in step S 209 ), the movement speed determination unit  403  selects a low speed (third speed) that is lower than the standard speed (first speed) and sets the lower speed as the movement speed (step S 210 ). The display control unit  405  performs control so as to cause the items to be sequentially displayed by the user interface  300  while causing the display image to be moved by scrolling at the standard speed (third speed) (step S 211 ). 
     At this time, the display image of  FIG. 9A  being moved by low-speed scrolling is displayed in the user interface  300 . 
     In contrast, if the line of sight of the user toward the user interface  300  does not change in step S 209  (“NO” in step S 209 ), the line-of-sight determination unit  404  determines whether or not a predetermined time period has elapsed while the line of sight of the user has not changed (step S 212 ). 
     If the predetermined time period has not elapsed (“NO” in step S 212 ), the processing returns to step S 209 . In contrast, if the predetermined time period has elapsed (“YES” in step S 212 ), the movement speed determination unit  403  selects a high speed (fourth speed) that is higher than the standard speed (first speed) and sets this high speed as the movement speed (step S 213 ). The display control unit  405  performs control so as to cause the items to be sequentially displayed by the user interface  300  while causing the display image to be moved by scrolling at the high speed (fourth speed) (step S 211 ). After that, the processing returns to step S 205 . 
     At this time, the display image of  FIG. 9B  being moved by high-speed scrolling is displayed in the user interface  300 . 
     According to the second example, the control device  400  causes the movement speed to change depending on whether or not the line of sight of the user toward the display image changes while the control device  400  causes the display image to move. 
     For example, in order to move the display image by scrolling to the item existing in a latter portion of the list, the user is not interested in a former portion of the list and starts to be careful so as to find his or her target item as the display approaches the latter portion. At this time, the line of sight of the user does not change in the former portion and changes in the latter portion due to a change of the position watched by the user in the user interface  300 . 
     At this time, in the former portion of the list, the line of sight of the user toward the user interface  300  has not changed for the predetermined time period. In this case, the control device  400  causes the higher speed (fourth speed) that is higher than the standard speed (first speed) to be set as the movement speed. This may reduce time taken for the user to find the target item. 
     In contrast, in the latter portion of the list, the line of sight of the user toward the display image changes while the display image is being moved. In this case, the control device  400  performs control for reducing the movement speed to a lower speed (in this case, to the third speed) that is lower than the standard speed (first speed). With this control, while the display image is being moved by scrolling, the display image is moved at a lower speed at a position of an item of interest to the user. Thus, the user may easily find his or her target item. 
     Although the information processing apparatus is exemplified by the image forming apparatus  1  in the above-described examples, this is not limiting. That is, the present exemplary embodiment is applicable to any of apparatuses as long as the apparatuses display information including plural items as a display image, and the display image is moved by scrolling. For example, the present exemplary embodiment is applicable to devices such as mobile phones, smart phones, and tablets that display a phonebook including names, telephone numbers, e-mail addresses, and so forth as items and devices such as PCs on which spreadsheet software that displays spread sheets operates. 
     Furthermore, in the above-described examples, the information processing system S is configured by providing the detection device  500  and the image forming apparatus  1  as the information processing apparatus as separate units. However, for example, the detection device  500  may be disposed in the image forming apparatus  1  so as to be integrated with the image forming apparatus  1 . 
     The foregoing description of the exemplary embodiment of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiment was chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.