Patent Publication Number: US-2019199868-A1

Title: Operation console, and electronic device and image processing apparatus provided with the operation console

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This nonprovisional application is a continuation of U.S. patent application Ser. No. 15/828,362, filed Nov. 30, 2017, which is a continuation of U.S. patent application Ser. No. 14/683,500, filed Apr. 10, 2015, which is a continuation of U.S. patent application Ser. No. 13/022,712, filed Feb. 8, 2011, which claims priority under 35 U.S.C. § 119(a) on Patent Application No. 2010-033289 filed in Japan on Feb. 18, 2010, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an operation console including a display unit for displaying information to a user. More specifically, the present invention relates to an operation console allowing the user to accurately select and operate an operation button for displaying a specific screen image (operation mode selecting screen image) on the display unit, from among a plurality of operation buttons. The present invention also relates to an electronic device and an image forming apparatus provided with such an operation console. 
     Description of the Background Art 
     As one type of image processing apparatuses as electronic equipment, image forming apparatuses forming images on recording paper (typically, copy machines) are introduced to many places of business (companies and offices). In such a place of business, it has become increasingly common to connect an image forming apparatus having a printer function or a copy function to a network, to allow use (sharing) by a plurality of users. A multifunction peripheral (MFP) as one type of such image forming apparatuses has a plurality of basic operation modes such as a copy mode, a facsimile mode (hereinafter “facsimile” may also be denoted as FAX or fax), a network-supported printer mode and a scanner mode. In such an image forming apparatus, each user selects an operation mode and sets a function of duplex (two-sided) printing or collective printing (such as 2-in-1 by which two pages of an original document are printed on one sheet, or 4-in-1 by which four pages of an original document are printed on one sheet), whereby images are formed on sheets of paper in a desired manner. Appropriate combinations of these functions come to be more frequently used. 
     When a user uses such an image forming apparatus, for example, the user inputs image data in the scanner mode, performs image processing (such as collection) by inputting various instructions through an operation panel, and prints the results on a sheet of recording paper. In such a situation, the operation panel, serving as an operation and display unit, functions as an interface between the image forming apparatus and the user. Generally, on the operation panel, a screen image for setting functions in each operation mode is displayed, so that the user can easily set various functions. Further, while a job is being executed, job progress status may be displayed, to allow the user to easily grasp the progress status of the job. In the printer mode executed upon reception of data from an external device, the job progress status may be displayed on the operation panel in accordance with the data received from the external device as a source. 
     Recently, a touch-panel display having a touch-panel overlapped on a liquid crystal panel (display panel) comes to be increasingly used as such an operation panel. By way of example, items (software buttons) allowing selection of a mode of the image forming apparatus are displayed on the touch-panel display, the user viewing the display presses a position of an item displayed on the touch-panel display (presses a software button), and the operation mode is set. 
     Such a touch-panel display having both the display and operation functions is advantageous in that it eliminates the necessity of providing a display unit and an operation unit separately. Further, it attracts attention recently since a command can be selected advantageously in accordance with the user&#39;s sense, when it is adapted such that a command can be selected in accordance with a trajectory of pressing of the touch-panel display by the user&#39;s finger. Examples of such command selection using finger trajectory include the following. 
     When a plurality of pages are displayed on the touch-panel display as print previews, the following operations may be performed. By a user operation of lightly tapping twice (hereinafter also referred to as double-tapping) a position of a certain page displayed as a preview, a command to display the page in an enlarged or reduced size can be selected. By a user operation trajectory of expanding a space between two fingers (hereinafter also referred to as pinch-out or pinch-open), a command to display the page in an enlarged size can be selected, and by a user operation trajectory of reducing a space between the two fingers (hereinafter also referred to as pinch-in or pinch-close), a command to display the page in a reduced size can be selected. In the following, these operations are denoted as gesture operations. The gesture operations are not limited to the above, and may include: tapping, or lightly touching an item displayed on the touch-panel display; dragging, or sliding an item with a finger; flicking, or lightly sweeping an item to scroll; and pinching with two fingers. It is noted that, strictly speaking, (different from other gesture operations) tapping and double-tapping are not determined by detecting the user operation trajectory on the touch-panel display. These are determined not by the trajectory but by detection of a position. Considering the relation to other gesture operations, in the present specification, the gesture operation generally refers to an operation for detecting a user request based on the operation trajectory of the user to the touch-panel display, including tapping and double tapping. 
     Further, in the present specification, an operation other than the gesture operations as such will be described as a touch operation. The touch operation means an operation of detecting a user&#39;s request based on the position of operation by the user on the touch-panel. A representative example of the touch operation is an operation of the user pressing a position of an item (pressing a software button) displayed on the touch-panel display. 
     In an MFP provided with a touch-panel display allowing both touch operation and gesture operation, many pieces of information intended for the user are displayed on the touch-panel display. Such an MFP has a plurality of operation modes as described above, and the user selects an operation mode. An operation mode may be selected by pressing a software button displayed on the touch-panel display, or by pressing a hardware button. 
     By way of example, Japanese Patent Laying-Open No. 2006-201585 (hereinafter referred to as &#39;585 Reference) discloses an operation panel device intended for improving operability by preventing operation error of any user. The operation panel device has a display unit on which an operation screen image can be displayed. The display unit of operation panel device provides color displays of a plurality of operation menu screen images, with background colors made different from each other. 
     In the operation panel device, the display unit is capable of color display of a plurality of operation menu screen images of respective operation menus, with background colors made different from each other. The user, noticing the background color of the operation menu screen image color-displayed on the display unit, can intuitively grasp the operation menu corresponding to the operation menu screen image. No matter who the user is, operation error in selecting the operation menu can be reduced, and improved operability can be attained. In FIG. 1 of &#39;585 Reference, a group of function switching keys including four keys to switch among the copy function, printer function, scanner function and facsimile function is arranged as software buttons, aligned on the right side of the touch-panel display. 
     Japanese Patent Laying-Open No. 2006-308831 (hereinafter referred to as &#39;831 Reference) discloses an image forming apparatus including a plurality of processing functions (copy function, facsimile function, scanner function, electronic mail function, etc.), that improves user operability by controlling screen image transitions. 
     The image forming apparatus includes: a display unit, displaying a menu screen image allowing selection of any of the plurality of processing functions, or a function instruction screen image allowing execution of a processing function; an operation unit, receiving a user operation related to the selected processing function, based on the screen image displayed on the display unit; a detection unit detecting absence of any operation, related to the selected processing function, on the operation unit for a prescribed time period; and a control unit, returning, if it is detected by the detecting unit that no operation is done for the prescribed time period, the screen image on the display unit to an initial display of the function instruction screen image related to the selected processing function. 
     The image forming apparatus is controlled such that, if no operation is done by the operation unit for a prescribed time period, the detecting unit detects the absence of operation, the function instruction screen image related to the processing function displayed on the display unit is reset, and the display is returned to the initial screen image of the function instruction screen image. Therefore, as an automatic reset process that takes place after the lapse of the prescribed time period, the initial screen image corresponding to the function that has been selected immediately before is resumed. Therefore, when the user is to proceed to the next process, the process function can readily be executed. FIG. 3(a) of &#39;831 Reference shows software buttons for switching among the copy function, scanner function and facsimile function, on the touch-panel display. 
     SUMMARY OF THE INVENTION 
     Various electronic devices as represented by the image forming apparatus and an image processing apparatus include a touch-panel display as a display device. As disclosed in the references described above, various pieces of information are displayed on the touch-panel display. 
     The image forming apparatus as one of such electronic devices has a plurality of functional modes or process functions (operation modes). When a user selects an operation mode, an initial screen image corresponding to the selected operation mode is displayed on the touch-panel display. 
     In the operation panel device disclosed in &#39;585 Reference, the operation mode is selected using a hardware button. In the operation panel device as such, it is necessary to provide hardware buttons at least same in number to the types of operation modes. The operation panel device disclosed in &#39;585 Reference is provided with a large number of hardware buttons including ten keys, a start key and a reset key, in addition to the operation mode selecting buttons corresponding to the four different operation modes. Therefore, a user may be confused in determining which hardware button is to be pressed for selecting an operation mode. Further, in the operation panel device disclosed in &#39;585 Reference, four keys for switching among the copy function, printer function, scanner function and facsimile function are arranged aligned on the right side of touch-panel display. Such arrangement is not very easily viewable to the user, possibly leading to an error of selecting an operation mode. 
     Buttons for selecting operation modes come to be implemented by software buttons displayed on the touch-panel display, rather than the hardware buttons. Software buttons are preferred since the arrangement and shape (size) can easily be changed. By way of example, it is easy to display the software button in a larger size or in different color to be more easily noticeable by the user. In the image forming apparatus disclosed in &#39;831 Reference, software buttons for switching operation modes are displayed on the touch-panel display. 
     However, &#39;831 Reference does not sufficiently disclose the user operation for making a transition to the menu screen image allowing selection of an operation mode. What is disclosed in &#39;831 Reference is simply that transition to the auto reset mode occurs in the absence of any operation for a prescribed time period after selection of an operation mode, and that the screen image after transition to the auto reset mode may be set either to the menu screen image or to the initial screen image of the selected operation mode. 
     Such a configuration may lead to the following problem. Assume that the user selects the copy mode as the operation mode, and is making various settings of the copy mode on the initial screen image of the copy mode. Here, it is often the case that the user has difficulty in operation and wishes to start the operation again from the selection of operation mode. However, it is difficult in the image forming apparatus disclosed in &#39;831 Reference for the user to operate the image forming apparatus smooth in such a situation. The reason is as follows. First, it is necessary to set in advance the screen image after transition to the auto reset mode to the menu screen image. Further, in order to return to the menu image if the user is confused in operation, the user must wait without any operation until auto reset starts. This prevents smooth operation by the user of the image forming apparatus. 
     In order to avoid such a situation, an image forming apparatus having a hardware button forcing the screen image on the touch-panel display to make a transition to the menu screen image has been known. Even in such an apparatus, it is often the case that a large number of hardware buttons are arranged on the operation panel as in the case of &#39;585 Reference, and the user having difficulty in operation could be confused, not knowing which hardware button should be pressed to return to the menu image. In that case, the user who wishes to return to the menu screen image may take a long time for operation, or may make an erroneous operation. 
     As a solution to such a problem, it is possible to provide only one hardware button to return to the menu screen image on the operation panel. In such an image forming apparatus, however, at least a power button and a button to enter/return to the energy saving mode, which cannot be implemented by the software buttons displayed on the touch-panel display, must be provided. Therefore, it is not practical to provide only the hardware button to return to the menu screen image on the operation panel. When a plurality of hardware buttons are provided on the operation panel, the problem that the user may be confused in selecting which hardware button to be pressed cannot be solved. 
     Therefore, an object of the present invention is to provide, in an electronic device and an image processing apparatus that operate in accordance with a user operation, a technique allowing the user to accurately select and operate a hardware button receiving a request to make a transition to the screen image displaying specific information, from among a plurality of hardware buttons. 
     The electronic device may be any device capable of operating in a plurality of operation modes, switched by a user operation. An example of the image processing apparatus is an image forming apparatus. The screen image to which the transition is made upon pressing the hardware button is, for example, a screen image allowing selection of an operation mode. 
     According to an aspect, the present invention provides an operation console provided on an apparatus as an object of control operated by a user operation. The operation console includes: a display device for displaying information to the user; an input device for the user to input a request; and a display control device displaying, if a request for displaying specific information on the display device is input through the input device, the specific information on the display device. The input device includes a plurality of operation buttons for inputting a plurality of requests, corresponding to respective requests. Among the plurality of operation buttons, an operation button corresponding to the request for displaying the specific information is provided closest to the display device. 
     The operation console is provided with a plurality of operation buttons (hardware buttons) as the input device. If a user has difficulty in operation and wishes to have specific information displayed on the display device, the user inputs a request to display the specific information, by operating a specific operation button among the plurality of operation buttons. The specific operation button is provided closest to the display device and, therefore, the user viewing the display device can easily and accurately select the specific button from the plurality of operation buttons. Therefore, the user request can easily and accurately be input, and the specific information can be displayed on the display device. Particularly, since the specific information (such as initial screen image information, help information, or mode selection information) can easily and accurately be displayed to the user having difficulty in operation, the user can avoid further trouble or difficulty. 
     The operation console is provided on an apparatus as an object of control operating in an operation mode selected by a user operation from among a plurality of operation modes. The specific information displayed on the display device is mode selection information allowing selection of one operation mode from the plurality of operation modes. 
     In this manner, if the user is making various settings in an operation mode once selected, and has difficulty in operation and wishes to restart from the selection of operation mode, the user may have the mode selection information displayed easily and accurately. 
     The display device may have a substantially rectangular planar display area in landscape layout. The plurality of operation buttons may be provided opposite to any side of the substantial rectangle. Of the plurality of operation buttons, the operation button corresponding to the request for displaying the specific information may be positioned closest to the said any side. The said any side may be a right, shorter side, or a lower, longer side of the substantial rectangle. 
     A plurality of operation buttons are provided collectively opposite to any side of the display device having a substantially rectangular, planar display area of landscape orientation. The flow line of the user&#39;s fingertip does not wastefully move to the left/right or upward/downward. Thus, user operability can be improved. 
     Preferably, the plurality of operation buttons include, in addition to the button corresponding to the request for displaying the specific information, an operation button for controlling electric power supplied to the apparatus as an object of control. 
     More preferably, the operation console further includes a touch-panel arranged overlapped on the display device, for detecting a request based on a position where a fingertip of a user touched. User operation other than the operation on the operation button corresponding to the request for displaying the specific information and on the operation button for controlling electric power supplied to the apparatus as an object of control is detected by the touch-panel. 
     The operation button controlling electric power supplied to the apparatus as the object of control cannot be implemented by a software button formed on the touch-panel. The operation button for controlling power supply and the operation button corresponding to the request for displaying the specific information are implemented by hardware buttons. Except for these buttons, other operation buttons are implemented by software buttons. As a result, the number of hardware buttons can significantly be reduced, and therefore, it is possible for the user to accurately and easily select the operation button corresponding to the request for displaying specific information from the hardware buttons. 
     Preferably, the operation button for controlling electric power includes a button requesting supply and stop of electric power to the apparatus as the object of control, and a button requesting execution and stop of an energy saving mode of the apparatus as the object of control. 
     The number of operation buttons is limited to three, that is, the power supply button requesting supply and stop of electric power to the apparatus as the object of control, an energy saving button requesting execution and stop of the energy saving mode in the apparatus as the object of control, and the operation button corresponding to the request for displaying the specific information. Therefore, it is possible for the user to accurately and easily select the operation button corresponding to the request for displaying specific information from the hardware buttons. 
     According to another aspect, the present invention provides an electronic device provided with the operation console described above. According to a still further aspect, the present invention provides an image processing apparatus provided with the above-described operation console. 
     In the electronic device and the image forming apparatus, it is possible for the user to accurately select and operate the operation button for causing a transition to a screen image allowing selection of an operation mode of the electronic device or the image forming apparatus, from a plurality of operation buttons. 
     According to the present invention, in the electronic device and the image forming apparatus operated by a user, it is possible for the user to accurately select and operate the hardware button receiving a request to make a transition to the screen image displaying specific information, from a plurality of hardware buttons. 
     The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an appearance of the image forming apparatus in accordance with an embodiment of the present invention. 
         FIG. 2  is a plan view of an operation unit of the image forming apparatus shown in  FIG. 1 . 
         FIG. 3  schematically shows an internal configuration of the image forming apparatus shown in  FIG. 1 . 
         FIG. 4  is a functional block diagram showing a hardware configuration of the image forming apparatus shown in  FIG. 1 . 
         FIG. 5  shows display areas of a touch-panel display of the image forming apparatus shown in  FIG. 1 . 
         FIGS. 6 and 7  show exemplary screen images displayed on the touch-panel display of the image forming apparatus in accordance with the embodiment of the present invention. 
         FIG. 8  is a plan view of an operation unit of the image forming apparatus in accordance with a first modification of the embodiment of the present invention. 
         FIG. 9  is a plan view of an operation unit of the image forming apparatus in accordance with a second modification of the embodiment of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following description, the same components are denoted by the same reference characters. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated. 
     The electronic device in accordance with an embodiment of the present invention is an image forming apparatus as one type of image processing apparatuses. The display device in accordance with the present invention may be applicable to an image processing apparatus or an electronic device other than the image forming apparatus. The electronic device in accordance with the present embodiment may be any apparatus having a plurality of operation modes and provided with an operation console capable of displaying a specific screen image (menu screen image (home screen image), help screen image, initial screen image etc.), for switching the operation mode, by pressing one hardware button among a plurality of hardware buttons. Here, the specific screen image displayed on the operation console is not limited to the home screen image. 
     The image forming apparatus in accordance with the present embodiment includes a touch-panel display allowing operation by the gesture operation method and the touch-operation method not using the gesture operation. The apparatus, however, may include a touch-panel display allowing touch operation only. Alternatively, the apparatus may include a display panel, capable of display only and not allowing any operation, and buttons for operation. 
     The image forming apparatus forms an image on a sheet of recording paper by electro-photography. The image forming apparatus includes, as operation modes, copy mode, FAX mode, document filing mode (a mode in which a scanned image is stored in a storage device in the image forming apparatus) and mail mode (a mode in which a scanned image is transmitted attached to an electronic mail). The image forming apparatus may further include network printer mode. The present invention is not limited to the above, and it may be any image forming apparatus including at least two of the four operation modes, that is, copy mode, FAX mode, document filing mode and mail mode, in which a home screen image allowing selection of an operation mode is displayed on the touch-panel display when a specific button among the plurality of hardware buttons is pressed. Further, the printing method is not limited to electro-photography. 
     [Image Forming Apparatus: Function] 
     Referring to  FIGS. 1 to 4 , an image forming apparatus  100  in accordance with the present embodiment will be described.  FIG. 1  shows an appearance of an image forming apparatus  100 .  FIG. 2  is a plan view of an operation unit of image forming apparatus  100 .  FIG. 3  schematically shows an internal configuration of image forming apparatus  100 .  FIG. 4  is a functional block diagram of image forming apparatus  100 . 
     Referring to  FIGS. 1 to 4 , image forming apparatus  100  includes a document reading unit  102 , an image forming unit  104 , a paper feed unit  106 , a paper discharge unit  108  and an operation unit  120 . As shown in  FIGS. 1 and 2 , operation unit  120  includes a touch-panel display  130  and a display operation unit  140 . Touch-panel display  130  includes a display panel  132  formed of a liquid crystal panel or the like, and a touch-panel  134  arranged overlapped on display panel  132 , for detecting a position pressed by the user&#39;s finger. Display operation unit  140  includes a pilot lamp  142 , a power key  144 , an energy-saving key  146 , and a home key  148  for returning the display screen image on touch-panel display  130  to a home screen image for selection of an operation mode. 
     As described above, image forming apparatus  100  in accordance with the present embodiment is provided with touch-panel display  130  as a main operation device, and, in addition, with display operation unit  140  including hardware buttons and a pilot lamp. The keys (power key  144 , energy-saving key  146  and home key  148 ) of display operation unit  140  are hardware buttons, in contrast to the software buttons realized by touch-panel display  130 . It is noted that image forming apparatus  100  is not limited to one having display operation unit  140  as such, and the invention is applicable to any apparatus in which display operation unit  140  is provided with a plurality of hardware buttons, and the home screen image is displayed on touch-panel display  130  (if the home screen image has not been displayed) when home key  148  among the plurality of hardware buttons is pressed. The display is switched to an initial screen image of a selected operation mode, when the user selects the operation mode on the home screen image displayed on touch-panel display  130 . The operation modes of image forming apparatus  100  as such will be described. 
     —Copy Mode— 
     In the following, an operation in the copy mode will be described. In the copy mode, mainly document reading unit (also referred to as a scanner unit)  102  and image forming unit  104  operate. 
     In image forming apparatus  100 , a document placed on a platen is read by document reading unit  102  as image data. The read image data is input to CPU  300  implemented, for example, by a microcomputer shown in  FIG. 4 . The image data is subjected to various image processing operations here, and the resulting image data is output to image forming unit  104 . 
     Image forming unit  104  is for printing an image of the document represented by the image data on a recording medium (in most cases, on a sheet of recording paper). Image forming unit  104  includes a photoreceptor drum  222 , a charger  224 , a laser scanning unit (hereinafter denoted as LSU)  226 , a developer  228 , a transfer device  230 , a cleaning device  232 , a fixing device  234  and a neutralizer, not shown. 
     In image forming unit  104 , a main feeding path  236  and a reverse feeding path  238  are provided, and a sheet of recording paper fed from paper feed unit  106  is fed along main feeding path  236 . Paper feed unit  106  draws out sheets of recording paper stacked on a paper feed cassette  240  or on a manual feed tray  242  one by one, and feeds the sheet of paper to main feeding path  236  of image forming unit  104 . 
     While the sheet of recording paper is fed along main feeding path  236  of image forming unit  104 , the sheet passes between photoreceptor drum  222  and transfer device  230 , and further passes through fixing device  234 , whereby printing is done on the sheet of recording paper. 
     Photoreceptor drum  222  rotates in one direction, and its surface is cleaned by cleaning device  232  and the neutralizer and, thereafter, uniformly charged by charger  224 . 
     LSU  226  modulates the laser beam based on the image data to be printed, and repeatedly scans the surface of photoreceptor drum  222  with the modulated laser beam in a main scanning direction, whereby an electrostatic latent image is formed on the surface of photoreceptor drum  222 . 
     Developer  228  develops the electrostatic latent image by supplying toner to the surface of photoreceptor drum  222 , and thus, a toner image is formed on the surface of photoreceptor drum  222 . 
     Transfer device  230  transfers the toner image on the surface of photoreceptor drum  222  to the sheet of recording paper passing between transfer device  230  and the photoreceptor drum  222 . 
     Fixing device  234  includes a heating roller  248  for heating the sheet of recording paper and a pressure roller  250  for pressing the sheet of recording paper. As the sheet of recording paper is heated by heating roller  248  and pressed by pressure roller  250 , the toner image that has been transferred to the sheet of recording paper is fixed on the sheet. A heater is heated by electric power supplied to fixing device  234  and controlled such that temperature of heating roller  248  attains to an appropriate temperature for fixing. When operation mode is changed to the energy saving mode, power supply to the heater is, for example, stopped or reduced. 
     At a position of connection between main feeding path  236  and reverse feeding path  238 , a separation pawl  244  is arranged. When printing is done only on one side of the sheet of recording paper, separation pawl  244  is so positioned that the sheet of recording paper fed from fixing device  234  is guided to paper discharge tray  246  or a paper discharge unit  108 . 
     When printing is done on both sides of the sheet of recording paper, separation pawl  244  is turned to a prescribed direction, so that the sheet of recording paper is guided to reverse feeding path  238 . The sheet of recording paper passes through reverse feeding path  238 , turned upside-down and again fed to main feeding path  236 , and while it is again fed along main feeding path  236 , printing is done on its rear surface, and thereafter the sheet is guided to paper discharge tray  246  or to paper discharge unit  108 . 
     The sheet of recording paper printed in the above-described manner is guided to paper discharge tray  246  or to paper discharge unit  108 , and discharged to paper discharge tray  246  or to any of paper discharge trays  110  of paper discharge unit  108 . 
     Paper discharge unit  108  may perform a process of sorting a plurality of printed sheets of paper to be output to different discharge trays  110 , a process of punching each sheet of recording paper or a process of stapling the sheets of recording paper. Assume that a number of copies of the printing are to be prepared. In that case, sheets of recording paper are sorted and discharged to paper discharge trays  110  such that each tray  110  contains each set of printed sheets, and the set of printed sheets in each tray  110  is stapled or punched. 
     —Facsimile Mode— 
     In the following, an operation in the facsimile mode will be described. In the facsimile mode, document reading unit (scanner unit)  102  and FAX communication unit  160  mainly operate for the transmission operation, and FAX communication unit  160  and image forming unit  104  mainly operate for the reception operation. 
     Transmission Operation 
     In image forming apparatus  100 , the facsimile mode is designated. A document placed on the platen is read by document reading unit  102  as image data. The read image data is input to CPU  300  implemented, for example, by a microcomputer shown in  FIG. 4 , the image data is subjected to various image processing operations here, and the resulting image data is output to a FAX communication unit (FAX communication unit  160  of  FIG. 3 ). 
     FAX communication unit  160  of image forming apparatus  100  on the transmitting side connects a designated transmitting side line to a designated transmission destination. FAX communication unit  160  converts the image data to communication data in compliance with facsimile transmission standard, and transmits the converted data to a facsimile machine (such as an image forming apparatus  100  having the facsimile function) on the receiving side. 
     Communication Operation 
     When the line is connected, a FAX communication unit  160  of image forming apparatus  100  on the receiving side detects a communication request signal from FAX communication unit  160  of image forming apparatus  100  on the transmitting side, and transmits an acknowledgement signal. Thereafter, by way of example, FAX communication units  160  on the transmitting and receiving sides pass performance information supported by transmitting side and receiving side, determine highest possible speed of communication and method of coding/code correction of image data, and set the method of communication of modems. Then, using the image signal format in compliance with the communication method, data is transmitted from FAX communication unit  160  of image forming apparatus  100  on the transmitting side to the FAX communication unit  160  of image forming apparatus  100  on the receiving side. When transmission ends, the line is disconnected. 
     Reception Operation 
     FAX communication unit  160  of image forming apparatus  100  on the receiving side converts the received data to image data and passes the data to an image forming unit  104 . The received data may be converted to image data at the image forming unit  104 . The image forming unit  104  prints an image of a document represented by the image data converted from the received data on a sheet of recording paper, in a manner similar to the operation in the copy mode described above. 
     —Document Filing Mode— 
     In the following, an operation in the document filing mode will be described. In the document filing mode, mainly document reading unit (scanner unit)  102  and image forming unit  104  operate. 
     In image forming apparatus  100 , a document placed on the platen is read by document reading unit  102  as image data. The read image data is input to CPU  300  and subjected to various image processing operations here. The resulting image data is stored in a storage device (hard disk drive  302  as will be described later) provided in image forming apparatus  100 . 
     The stored image data is read from the hard disk drive by the user designating the file name, and printed on a sheet of recording paper in the similar manner as in the copy mode described above. 
     —Mail Mode (Scan-to-Mail)— 
     In the following, description will be given on an operation in the mail mode. In the mail mode, document reading unit (scanner unit)  102  and network interface  304  mainly operate. 
     The image communication mode provided in image forming apparatus  100  includes the facsimile mode in which image data is transmitted/received by public line through FAX communication unit  160 , and the electronic mail communication mode (mail mode) in which the image data is transmitted/received by the Internet line in the form of an attachment to an electronic mail, through network interface  304 . Image forming apparatus  100  may further include Internet facsimile mode in which the image data is transmitted/received by the Internet line through network interface  304 , or image transfer mode (scan-to-PC folder) in which the image data is transferred to a folder of a specific personal computer (PC) using a network line. 
     In image forming apparatus  100 , a document placed on a platen is read by document reading unit  102  as image data. The read image data is input to CPU  300 , and subjected to various image processing operations here. The resulting image data is transmitted, attached to an electronic mail. 
     Different from the facsimile mode in which a telephone number of transmission destination is designated, a mail address of the transmission destination is designated in the mail mode. 
     [Image Forming Apparatus: Control Block Configuration] 
     Referring to  FIG. 4 , image forming apparatus  100  further includes operation unit  120 , which allows setting of functions related to the copy mode, facsimile mode, document filing mode and mail mode; ROM (Read Only Memory)  306 , which stores programs and the like; a hard disk drive (hereinafter denoted as HDD)  302 , which is a non-volatile storage area capable of storing programs and data even when power is cut off; and an RAM (Random Access Memory)  308 , which provides a storage area when a program is executed. 
     Image forming apparatus  100  further includes: a bus  310  connected to document reading unit  102 , image forming unit  104 , FAX communication unit  160 , operation unit  120 , ROM  306 , HDD  302 , and RAM  308 ; and CPU  300  connected to bus  310 , for realizing general functions as the image forming apparatus. 
     HDD  302  stores files of image data of documents scanned by image forming apparatus  100 , folder by folder, together with date and time of saving and name of the user who saved. Further, HDD  302  stores initial screen image data of each operation mode. 
     ROM  306  stores programs and data necessary for controlling operations of image forming apparatus  100 . The initial screen image data of each operation mode may be stored as data to be stored together with the program in ROM  306 . CPU  300  controls image forming apparatus  100  in accordance with the programs and data stored in ROM  306 , and executes control related to various functions of image forming apparatus  100 . 
     As shown in  FIG. 4 , a public line is connected for transmitting/receiving image data, to FAX communication unit  160  of image forming apparatus  100 . To network interface  304 , a network line is connected. To the network line, a computer or the like using image forming apparatus  100  as a network-supported printer may be connected. To the network line, a computer or the like identified by a URL (Uniform Resource Locator) designated through the Internet may be connected. When connected to the Internet, image forming apparatus  100  can obtain necessary information through the Internet. 
     RAM  308  provides a function of a working memory for temporarily storing results of operations and processes by CPU  300 , and a function of a frame memory for storing image data. 
     CPU  300  controls document reading unit  102 , image forming unit  104 , ROM  306 , HDD  302 , RAM  308  and touch-panel display  130  and display operation unit  140  forming operation unit  120 , by executing a prescribed program or programs. Operation unit  120  communicates with CPU  300  through an input/output interface. 
     Operation unit  120  is formed of a plate-shaped panel provided in an inclined manner to be easily viewable by the user. On a surface of operation unit  120 , touch-panel display  130  is provided on the left side area, and display operation unit  140  (pilot lamp  142 , and power key  144 , energy-saving key  146  and home key  148  as hardware buttons) is provided on the right side area. Touch-panel display  130  and display operation unit  140  form operation unit  120  as one integrated body as a whole. 
     As described above, touch-panel display  130  is formed of display panel  132  and touch-panel  134  arranged overlapped on display panel  132 . On display panel  132  of touch-panel display  130 , a home screen image allowing selection of an operation mode of image forming apparatus  100 , current state of image forming apparatus  100 , status of destination designation, and status of job processing are displayed. On a display area of display panel  132 , selection buttons as software buttons are displayed. When a portion where the selection button is displayed is pressed, the pressed position is detected by the touch-panel  134 . By comparing the display position of the selection button and the position where the touch-panel  134  is pressed using a program, selection of an operation mode, setting of a function, and instruction of an operation of image forming apparatus  100  become possible. In addition to such a touch operation (command input operation based on the position of pressing by the user), image forming apparatus  100  also allows gesture operation (command input operation based on trajectory of operation by the user) as described above. 
     Pilot lamp  142  of display operation unit  140  is, for example, an LED (Light Emitting Diode). It is turned on/off (/flickered) under the control of CPU  300 . When the user presses power key  144  provided separate from a main power switch, image forming apparatus  100  makes a transition from a standby mode (in which, for example, only the FAX receiving operation is possible with the main power on) to a normal mode, in which every operation mode of image forming apparatus  100  is usable. In this state, pilot lamp  142  is turned and kept on. If a predetermined time passes without any user operation, or if the user presses energy-saving key  146 , image forming apparatus  100  makes a transition from the normal mode to the energy saving mode. In the energy saving mode, only some of the operation modes of image forming apparatus  100  can be used. In this state, pilot lamp  142  flickers. Further, if the user presses energy-saving key  146  in the energy saving mode, the image forming apparatus  100  makes a transition from the energy saving mode to the normal mode. Home key  148  is a hardware key for returning the display of touch-panel display  130  to the initial state (home screen image). The processes performed when power key  144 , energy-saving key  146  and home key  148  are pressed are not limited to the above. 
     Referring to  FIGS. 1 and 2 , planar arrangement of operation unit  120  will be described in detail. Most part of the upper surface of operation unit  120  serves as the display area of rectangular touch-panel display  130 . On the right, shorter side of touch-panel display  130 , display operation unit  140  (pilot lamp  142 , power key  144 , energy-saving key  146  and home key  148 ) is provided. 
     As shown in  FIG. 2 , the appearance of home key  148  has the following characteristics: (1) it is arranged closer to touch-panel display  130 ; (2) its size (area projected on the upper surface of operation unit  120 ) is large; (3) it has a rectangular shape in portrait orientation; and (4) it is formed integrally with touch-panel display  130 . 
     Because of the characteristic shape (3), the length opposite to the shorter side of touch-panel display  130  (the length of the neighboring, or adjacent portion) can be made longer, and hence integrity with the touch-panel display  130  can be enhanced. Specifically, if home key  148  is provided on the left or right side of touch-panel display  130 , home key  148  is adapted to have a rectangular shape in portrait orientation, and if home key  148  is provided on the upper or lower side of touch-panel display  130 , home key  148  is adapted to have a rectangular shape in landscape orientation, so as to enhance integrity with touch-panel display  130 . The integrity of (4) refers to the design that a member (a box, a line, or a member of rugged surface surrounding peripheral edges of touch-panel display  130 ) arranged around the peripheral edge of rectangular touch-panel display  130  is protruded near home key  148 , to enclose home key  148 . Thus, oneness of touch-panel display  130  and home key  148  can effectively be appealed to the user, relation between the devices (display device and operation device) is recognized, and hence, pressing of home key  148  is encouraged. 
     Further, the entire upper surface of operation unit  120  is of achromatic color (black). This is preferred since the state of pilot lamp  142  indicating the status of image forming apparatus  100  is easily recognizable, for example, in the energy saving mode. Particularly if touch-panel display  130  is of a large size, measures to save energy is important and, therefore, at least power key  144  and energy-saving key  146  are provided separately as hardware buttons, so that the apparatus can be set to the standby state not allowing any operation. Since it is impossible to supply power partially to the display area of touch-panel display  130  (to partially render conductive), touch-panel display  130  turns black without any display in the energy saving mode. In this respect, since the panel body of the upper surfaces of touch-panel display  130  and operation unit  120  is all black, pilot lamp  142  is better noticed. 
     The planar arrangement of power key  144 , energy-saving key  146  and home key  148  will be described. As shown in  FIG. 2 , these three hardware buttons (keys) are arranged such that the center line  148 C of home key  148  is positioned closer to the side of touch-panel display  130  than the center line  144 C of power key  144  and the center line  146 C of energy-saving key  146 . Further, these three hardware buttons (keys) are arranged such that the edge line  148 E is positioned closer to the side of touch-panel display  130  than the edge line  144 E of power key  144  and the edge line  146 E of energy-saving key  146 . Edge line  148 E of home key  148  represents the position of the outer edge on the opposite side of (away from) touch-panel display  130 , and edge line  144 E of power key  144  and edge line  146 E of energy-saving key  146  both represent positions of the outer edge on the side of (close to) touch-panel display  130 . 
     Though not limiting, in image forming apparatus  100 , pilot lamp  142  is arranged between the center line  148 C and edge line  148 E of home key  148 . 
     In a hardware button (power key  144 , energy-saving key  146  and home key  148 ) of display operation unit  140 , a key lamp or key lamps, which is turned on/off (/flickered) under the control of CPU  300 , may be embedded. By way of example, the key lamps provide a light ring on the edge of a circular key, or the key lamp lights a central portion of the key. The key lamp is turned on at a timing when hardware buttons are allowed to be used as the operation device (at a timing when a process is executed if the hardware button is used). 
     Image forming apparatus  100  in accordance with the present embodiment includes the four operation modes (copy mode, facsimile mode, document filing mode and mail mode) as described above. On touch-panel display  130 , software buttons for setting functions in respective operation modes are displayed, and buttons for setting a destination or a preview as an expected image, for example, are displayed as needed. 
     In different operation modes, different screen images are displayed on touch-panel display  130 . In order to allow the user to easily find a required piece of information even in such a state, touch-panel display  130  is divided into a plurality of areas (with the size of each area made variable), and pieces of information are displayed in these areas. More specifically, in image forming apparatus  100 , if an operation mode is selected on the home screen image of touch-panel display  130  provided as a main display operation device, the initial screen image of each operation mode is displayed. The initial image has the following characteristics. 
     (1) The basic layout is such that the screen image is divided into five areas (“system area,” “function selecting area,” “preview area,” “action panel area,” and “task trigger area”) and arranged appropriately. Therefore, by a user operation starting from an upper left portion to a lower right portion, easy setting is possible. The reason for this is that the flow lines of the user&#39;s viewpoint and finger tip are similar to those in a conventional device not provided with such a large touch-panel display  130 . 
     (2) Concepts of the pieces of information displayed on respective ones of the five areas are common among different operation modes, so that smooth operation by the user without any confusion becomes possible even in different operation modes. 
     In the following, the arrangement of basic layout will be described. 
     [Basic Layout Arrangement] 
       FIG. 5  shows a basic layout on touch-panel display  130  of image forming apparatus  100 . Referring to  FIG. 5 , the basic layout of landscape-oriented touch-panel display  130  (for example, of 1024 pixels×600 pixels) includes: system area  1000  arranged at the uppermost portion; preview area  3000  arranged at the center of the screen image; function setting/confirmation area  2000  (hereinafter referred to as function selecting area  2000 ) placed on the left side of preview area  3000 ; action panel area  4000  placed on the right side of preview area  3000 ; and task trigger area  5000  placed on the lower right side of preview area  3000 . The number of areas is not limited to five, the arrangement on the left and right sides is not limited to the above, and the layout may be customized to facilitate user operation. For instance, system area  1000  may be positioned at the lowermost portion of the screen image. 
     On system area  1000 , pieces of information related to the current status, title of the operation mode that is being selected, and state of image forming apparatus  100  are displayed. By way of example, on system area  1000 , an operation mode name, an interruption key, a log-in user name, status of a currently processed job, state of use of an internal memory, time and the like are displayed. 
     On function selecting area  2000 , a function selection menu (icons, buttons and the like) operated by the user for setting each function, switching display and confirming setting, is displayed. The manner of display of function selecting area  2000  is changed depending on whether it is in an icon mode, a regular mode or an express mode. In the icon mode, only the icons for setting functions are displayed in function selecting area  2000 , so as to ensure the widest preview area  3000 . In the express mode, a large screen image allowing setting of functions at one time is displayed in function selecting area  2000 , while preview area  3000  is made the smallest. In the regular mode, the size of preview area  3000  is medium size between that in the icon mode and that in the express mode. In function selecting area  2000 , function names are displayed in text, together with the icons for setting functions. 
     Switching among the icon mode, regular mode and express mode is done based on an operation by the user. Specifically, the size of preview area  3000  is changed in accordance with the user&#39;s operation. Since icons can transmit pieces of information to the user in a small area, it is preferred to prepare icons for all functions, so as to allow display of preview area  3000  in a large size. 
     At a lower portion of function selecting area  2000 , a group of change buttons  2010  are provided, for changing style of display of function selecting area  2000 . Among the group of change buttons  2010 , provided are: an icon mode entering button  2012  for displaying function selecting area  2000  in the icon mode; a “favorite” button  2014  for displaying functions registered as “favorites”; a check button  2016  for displaying a function of which setting has been changed; a list button  2018  for displaying a list of all functions that can be set in the selected operation mode; a regular mode entering button  2020  for displaying function selecting area  2000  in the regular mode; and an express mode entering button  2022  for displaying function selecting area  2000  in the express mode. 
     If a large amount of information is to be displayed on function selecting area  2000 , pieces of information are displayed in an upward/downward scrollable manner. In that case, the group of change buttons  2010  are not scrolled but constantly displayed at the lowermost portion of function selecting area  2000 . 
     In preview area  3000 , an image of expected document output (finished form) is displayed. Specifically, an image is displayed using dummy data or scanned data. Every time the user designates the manner of finish, the image displayed on preview area  3000  changes. Preview area  3000  has two display modes, that is, a virtual mode before scanning, in which finished form of a dummy image is displayed, and a scan-in mode after scanning, in which finished form of the actual image is displayed. The virtual mode has two types, that is, before setting an original document and after setting an original document. 
     At a lower portion of preview area  3000 , a group of preview changing buttons  3010  are arranged, for changing the style of display of preview area  3000 . Among the group of preview changing buttons  3010 , provided are: a left-turn button  3016  for turning the preview 90 degrees to the left; a right-turn button  3018  for turning the preview 90 degrees to the right; and a zoom bar  3020 . In addition to these buttons, a color changing button  3012  and preview operation button  3014 , for example, are provided. 
     When left-turn button  3016  is touch-operated once, the preview is turned 90 degrees to the left, and when touch-operated twice, the preview is turned 180 degrees to the left. Similarly, when the image of finished document displayed on the preview area is gesture-operated (when the document image is rotated 90 degrees or 180 degrees counterclockwise by one&#39;s finger), the preview is turned 90 degrees or 180 degrees to the left. 
     When right-turn button  3018  is touch-operated once, the preview is turned 90 degrees to the right, and when touch-operated twice, the preview is turned 180 degrees to the right. Similarly, when the image of finished document displayed on the preview area is gesture-operated (when the document image is rotated 180 degrees clockwise by one&#39;s finger), the preview is turned 180 degrees to the right. 
     When a plus button  3020 A of zoom bar  3020  is touch-operated or if bar  3020 C is gesture-operated (slid) to the side of plus button  3020 A, the preview is displayed in an enlarged size. Similarly, when the image of finished document displayed on the preview area is gesture-operated (when the document image is pinched-out/pinched-open by finger tips), the preview is displayed in an enlarged size. 
     When a minus button  3020 B of zoom bar  3020  is touch-operated or if bar  3020 C is gesture-operated (slid) to the side of minus button  3020 B, the preview is displayed in a reduced size. Similarly, when the image of finished document displayed on the preview area is gesture-operated (when the document image is pinched-in/pinched-close by finger tips), the preview is displayed in a reduced size. 
     If the number of pages of the document image to be displayed on preview area  3000  is large, a display page selection button (a page number input button, page feed button, page return button, single page display button, plural page display button or the like) that can be touch-operated may be displayed. Page feed and page return of the previewed document is also possible by a gesture-operation (flick) of the document image. If the document image displayed on preview area  3000  is large, a scroll bar that can be touch-operated or gesture-operated may be displayed. 
     On action panel area  4000 , pieces of information related to assistance, guidance and suggestion related to the operation are displayed. On action panel area  4000 , if, for instance, a user selects a specific function, functions related to the selected function may be displayed, other functions related to the selected function in object-oriented manner may be displayed, or functions selected in the past by the user or a user of a group to which the user belongs in relation to the selected function may be displayed as “recommended functions.” 
     On task trigger area  5000 , trigger items operated by the user to actually operate image forming apparatus  100  when all settings are done for the operation mode are displayed. By way of example, a start button (software button) is displayed for starting a process. In an operation mode involving printing (other than facsimile transmission), information related to run out of consumables is also displayed on the “task trigger area,” since it leads to a task failure. 
     Here, it is preferred to display the start button only when the state allows pressing of the start button. The state that allows pressing of the start button refers to a state in which all settings have been done, and consumables (recording paper and toner) are available, in the operation mode involving printing. In the facsimile mode (transmission) as an operation mode not involving printing, it is a state in which settings of all transmission parameters including a destination have been done. 
     The positions where these five areas are arranged are not changed even when the operation mode is changed (not changed in the initial screen image of any operation mode). Similar to the switched display in the icon mode/regular mode/express mode of function selecting area  2000  (and preview area  3000 ), the size of each area is changed, reduced/enlarged in the lateral direction (longitudinal direction) of touch-panel display. 
     These five areas are arranged in consideration of the flow line of user&#39;s viewpoint and the flow line of user&#39;s operation, in addition to the user interface of conventional devices. With such an arrangement, the user&#39;s viewpoint moves from upper left to lower right, and the user operation (finger tip of the dominant hand) moves from upper left to lower right. This advantageously enables a user-friendly operation. 
     For making a transition from one operation mode to another, home key  148  is pressed, to select another operation mode on the home screen image. In this manner, the operation mode is switched through the home screen image. 
     As described above, image forming apparatus  100  is provided with touch-panel display  130  on which the home screen image is displayed when home key  148  is pressed by the user. Such a display process is realized by software executed by using the hardware configuration described above. 
     Basically, no matter what screen image is displayed on touch-panel display  130 , if it is detected that home key  148  is pressed, CPU  300  of image forming apparatus  100  executes the program of displaying the home screen image on touch-panel display  130 . CPU  300  executes, in parallel with the program, a program for realizing general functions of an image forming apparatus. The program, however, is not directly related to the characteristic portion of the present invention and, therefore, details thereof will not be described here. It is also possible to change the manner of control of image forming apparatus  100  (particularly, the manner of control related to the display of touch-panel display  130 ) by pressing home key  148  for a long time or by pressing the key twice. 
     [Operation] 
     The operation of image forming apparatus  100  in accordance with the present embodiment based on the configuration and flowchart as above will be described with reference to the exemplary displays on touch-panel display  130  shown in  FIGS. 6 and 7 . 
     —Home Screen Image Display Operation— 
     When the user presses power key  144  of image forming apparatus  100 , the warm-up screen image is displayed on touch-panel display  130  until warm-up is complete. At this time, it is preferred that image forming apparatus  100  prepares pieces of information that can be displayed even during system check and useful for the user who is going to use image forming apparatus  100 , and that the warm-up screen image including such pieces of information is displayed on touch-panel display  130 . 
     When warm-up is complete, the home screen image is displayed on touch-panel display  130 . At this time, on touch-panel display  130 , a home screen image  6000  such as shown in  FIG. 6  is displayed. On home screen image  6000 , not all of the five areas of the layout described above are displayed. As shown in  FIG. 6 , on home screen image  6000 , icons (icons representing operation modes) allowing selection of an operation mode are displayed on most part of touch-panel display  130 , regardless of the five areas. The number of icons to be displayed on home screen image  6000  may be customized, for example, in three stages, of “large,” “middle” and “small.” 
     Referring to  FIG. 6 , home screen image  6000  includes a home system area  6100  corresponding to the system area described above, an icon display area  6200 , an icon display switching tub-button  6300 , and a memo display area  6400 . 
     On home system area  6100 , an area  6102  displaying an icon representing the home screen image, an area  6104  displaying the name of the displayed screen image, an area  6106  displaying the logged-in user name, an area  6108  displaying a log-out button (software button), and an area  6110  displaying the current time, are arranged. 
     On icon display area  6200 , icons  6210 - 6274  representing operation modes are displayed together with the names or abbreviations of the operation modes. The name or abbreviation of the operation mode is not indispensable. In the present embodiment, there are at least four operation modes (copy mode, facsimile mode, document filing mode, and mail mode). Therefore, an icon  6242  for selecting the copy mode, an icon  6232  for selecting the facsimile mode, an icon  6254  for selecting the document filing mode and an icon  6240  for selecting the mail mode are displayed on icon display area  6200 . In  FIG. 6 , icons for selecting other operation modes, icons for selecting other setting modes (for example, system setting and language setting), and icons for displaying other screen images (for example, job status) are also displayed. 
     As shown in  FIG. 6 , in icon display area  6200 , icons on the central column (for example, icons  6240 ,  6242  and  6244 ) are displayed larger than icons on the left and right sides thereof (for example, icons  6230  and  6250  with respect to icon  6240 , icons  6232  and  6252  with respect to icon  6242 , and icons  6234  and  6254  with respect to icon  6244 ). In icon display area  6200 , icons at the central row (for example, icons  6232 ,  6242  and  6252 ) are displayed larger than icons on the upper and lower sides thereof (for example, icons  6230  and  6234  with respect to icon  6232 , icons  6240  and  6244  with respect to icon  6242 , and icons  6250  and  6254  with respect to icon  6252 ). In this manner, in icon display area  6200 , the icons are displayed to be horizontally and vertically symmetrical in size, with the size being the largest at the center (center at the central column). 
     When the user makes a flick operation to the left with his/her finger on icon display area  6200  displayed on the screen of touch-panel display  130 , icons displayed on the screen move as if they flow in the direction indicated by an arrow  6010 . When the user makes a flick operation to the right, icons displayed on the screen move as if they flow in the direction indicated by an arrow  6020 . The distance of movement is determined, for example, in accordance with the width of movement of the finger tip in the flick operation. The distance of movement may be a prescribed distance set in advance for one flick operation. If a manner of display in which a plurality of icons are arranged on a virtual cylinder is adopted for icon display area  6200 , it becomes possible to display the icons in an endless manner. 
     On memo display area  6400 , a piece of maintenance information or the like to be notified to every user of image forming apparatus  100  is displayed. 
     —Operation of Displaying Initial Screen Image of Copy Mode— 
     If icon  6242  shown in  FIG. 6  is touched, tapped or double tapped by the finger tip of a user, it is determined that the operation mode is selected. If the selected operation mode is the copy mode, the initial screen image of copy mode is displayed on touch-panel display  130 . By way of example, an initial screen image  7100  for the copy mode shown in  FIG. 7  is displayed on touch-panel display  130 . As shown in  FIG. 7 , copy mode initial screen image  7100  is divided into five areas of the layout described above, on which pieces of information are displayed. 
     Referring to  FIG. 7 , on system area  1000  of copy mode initial screen image  7100 , an area  1102  indicating the selected operation mode (here, copy mode), an area  1104  displaying sub information related to the selected operation mode, an area  1106  displaying the logged-in user name, an area  1108  displaying a log-out button (software button), an area  1110  displaying the job status of the currently executed job, an area  1112  displaying a button related to the job status (software button), an area  1114  displaying the communication state, and an area  1116  indicating the current time, are arranged. 
     In area  1102 , a name and/or icon representing the operation mode is displayed. It is preferred that if area  1102  is touched, tapped or double-topped, a menu showing operation modes is pulled-down, allowing switching of the operation mode (the same applies to other operation modes). 
     In area  1104 , an interruption key (software button) is displayed as sub information. If the interruption key is touched, tapped or double-tapped, an interruption process can be executed in the copy mode. 
     In area  1106 , job status of the currently executed job is indicated by an icon. If the job status is touched, tapped or double-tapped, detailed information of job status is displayed. Further, it is preferred to display a button or the like to stop the selected job in area  1112 . 
     In function selecting area  2000  of copy mode initial screen image  7100 , a function selection menu allowing selection by the user in the copy mode and the group of change buttons  2010  described above are displayed. In the screen image shown in  FIG. 7 , the function selection menu is displayed in the regular mode. 
     As shown in  FIG. 7 , the function selection menu displayed in the regular mode includes a group of icons  2100  and a group of texts  2120 . In the function selection menu displayed on function selecting area  2000 , displayed are: an icon  2102  for setting the number of copies, and a text  2122  showing the set contents; an icon  2104  for setting color mode, and a text  2124  showing the set contents; an icon  2106  for setting copy density, and a text  2126  showing the set contents; an icon  2108  for setting copy magnification, and a text  2128  showing the set contents; an icon  2110  for setting document type, and a text  2130  showing the set contents; an icon  2112  for setting paper type, and a text  2132  showing the set contents; an icon  2114  for image edition, and a text  2134  showing the set contents; and an icon  2116  for layout edition, and a text  2136  showing the set contents. 
     As described above, further items on the function setting menu may be displayed in upward/downward scrollable manner, with the display position of group of change buttons  2010  fixed. It is possible to switch the items displayed on the function setting menu including the items hidden at the upper or lower portion and not displayed, either by the touch-operation (scroll operation) or gesture-operation (upward/downward flick operation). 
     Here, image edition refers to image edition of one page of document. A lower layer menu thereof includes frame erasure, print menu, watermark, user stamp and the like. The layout edition refers to image edition of a plurality of pages of the document. The lower layer menu thereof includes page collection, margin, page movement, centering and the like. The lower layer menu of the displayed function selection menu appears on touch-panel display  130  if any of icons  2102  to  2116  or texts  2122  to  2136  is touched, tapped or double-tapped. 
     In preview area  3000  of copy mode initial screen image  7100 , an image of expected document output (finished form)  3100  and the group of preview changing buttons  3010  described above are arranged. Here, image  3100  is displayed using dummy data or scanned data. Every time the user changes the function setting menu of function selecting area  2000 , image  3100  is changed and displayed on preview area  3000  (preview display is changed). 
     In action panel area  4000  of copy mode initial screen image  7100 , pieces of information related to assistance, guidance and suggestion related to the copy operation are displayed. As shown in  FIG. 7 , recommended functions in the copy mode selected by the user are displayed. In action panel area  4000 , an area  4100  showing the contents of displayed information, and areas  4102  to  4106  showing, as texts, the recommended functions and serving as software buttons are arranged. 
     When area  4102  is touched, tapped or double-tapped, detailed information of energy-saving copy is pulled-down and displayed. Here, a software button allowing transition to a function setting screen image for double-sided copy is displayed, together with a text message of, for example, “double-sided copy saves paper.” At the same time, a software button allowing transition to a function setting screen image for page collection is displayed, together with a text message of “collective printing of pages saves paper.” Further, a software button allowing transition to a function setting screen image for saddle stitch is displayed, together with a text message of “printing for bookbinding available.” 
     In task trigger area  5000  of copy mode initial screen image  7100 , a group of execution buttons  5100  is displayed. The group of execution buttons  5100  include: a scan-in key  5102  (software button) for operating image forming apparatus  100  to scan a document and obtain image data; a clear all key  5104  (software button) for clearing set function or functions; a monochrome start key  5106  (software button) for operating image forming apparatus  100  to scan a document and start copying in black and white; and a color start key  5108  (software button) for operating image forming apparatus  100  to scan a document and start color copying. 
     On copy mode initial screen image  7100  having pieces of information displayed on five divided areas, the user inputs various requests. Though the operation mode is not limited to the copy mode, after selecting an operation mode, it is possible that the user has difficulty in operation in the process of inputting requests in the operation mode. In such a situation, the user may wish to have the display on touch-panel display  130  to the home screen image and to start again from the selection of operation mode. If the user so wishes, he/she may simply press home key  148  provided on operation unit  120 . Here, it is possible for the user to easily find the home key  148  provided as integral part of touch-panel display  130 . 
     When home key  148  is pressed by the user, the display makes a transition from the screen image of  FIG. 7  to the screen image of  FIG. 6 . Here, the setting (for example, the number of copies set to 10 on the screen image of  FIG. 7 ) made by that time by the user may or may not be saved. If it is saved, after transition of the screen image from  FIG. 7  to  FIG. 6 , when icon  6242  shown in  FIG. 6  is touched, tapped or double-tapped by the user&#39;s finger, the initial screen image of the copy mode appears on touch-panel display  130 , and the saved setting is displayed. 
     Effects of the Present Embodiment 
     As described above, in the image forming apparatus in accordance with the present embodiment, the home key for switching the display on the touch-panel display to the home screen image allowing selection of an operation mode is provided to have integrity with the touch-panel display. Specifically, the home key is (1) arranged closer to the touch-panel display than other hardware buttons (power key and energy saving key), (2) larger than other hardware buttons, (3) adapted to have a rectangular shape in portrait orientation (while the touch-panel display is in landscape orientation), and (4) the box portion of home key and the box portion around the touch-panel display are surrounded by the same member. Because of such a shape, arrangement and structure of the home key, the touch-panel display and the home key are integral and, hence, the user who wishes to have the display on touch-panel display returned to the home screen image can easily find the home key. Therefore, operability of home screen display required by the user can be improved. 
     &lt;First Modification&gt; 
     Next, referring to  FIG. 8 , a first modification of the image forming apparatus in accordance with the present embodiment will be described. The image forming apparatus in accordance with the present modification differs from the embodiment above ( FIG. 2 ), in the arrangement of power key  1144 , energy-saving key  1146  and home key  1148  on operation unit  1120 . Except for these points, the modification and the embodiment above are the same and, therefore, detailed description thereof will not be repeated here. 
     As shown in  FIG. 8 , most part of the upper surface of operation unit  1120  serves as the display area of rectangular touch-panel display  130 . On the right, shorter side of touch-panel display  130 , pilot lamp  1142 , power key  1144 , energy-saving key  1146  and home key  1148  are provided. As shown in  FIG. 8 , pilot lamp  1142 , power key  1144  and energy-saving key  1146  are arranged aligned in the left/right direction (though the arrangement is not limited to such alignment in the left/right direction). Specifically, the center line  1144 C of power key  1144  is the same as the center line of energy-saving key  1146 . Further, in the present modification, since power key  1144  and energy-saving key  1146  have the same size, edge line  1144 E of power key  1144  is the same as edge line of energy-saving key  1146 . 
     The planar arrangement of power key  1144 , energy-saving key  1146  and home key  1148  will be described. As shown in  FIG. 8 , these three hardware buttons (keys) are arranged such that the center line  1148 C of home key  1148  is positioned closer to the side of touch-panel display  130  than the center line  1144 C of power key  1144  (which is also the center line of energy-saving key  1146 ). Further, these three hardware buttons (keys) are arranged such that the edge line  1148 E of home key  1148  is positioned closer to the side of touch-panel display  130  than the edge line  1144 E of power key  1144  (which is also the edge line of energy-saving key  1146 ). The edge line  1148 E of home key  1148  indicates the position of the edge opposite to (away from) the touch-panel display  130 , and edge line  1144 E of power key  1144  and energy-saving key  1146  indicates the position of the edge on the side of (closer to) touch-panel display  130 . 
     Though not limiting, as shown in  FIG. 8 , in the image forming apparatus, pilot lamp  1142  is arranged on the center line  1144 C of power key  1144  (which is also the center line of energy-saving key  1146 ). 
     As described above, in the image forming apparatus in accordance with the present modification, the home key for switching the display of touch-panel display to the home screen image allowing selection of an operation mode is provided to be integral with the touch-panel display and, therefore, the user can easily find the home key. 
     &lt;Second Modification&gt; 
     In the following, referring to  FIG. 9 , a second modification of the image forming apparatus in accordance with the present embodiment will be described. The image forming apparatus in accordance with the present modification differs from the embodiment above ( FIG. 2 ), in the arrangement of power key  2144 , energy-saving key  2146  and home key  2148  on operation unit  2140 . Except for these points, the modification and the embodiment above are the same and, therefore, detailed description thereof will not be repeated here. 
     As shown in  FIG. 9 , most part of the upper surface of operation unit  2140  serves as the display area of rectangular touch-panel display  130 . On the lower, longer side of touch-panel display  130 , pilot lamp  2142 , power key  2144 , energy-saving key  2146  and home key  2148  are provided. As shown in  FIG. 9 , pilot lamp  2142 , power key  2144  and energy-saving key  2146  are arranged aligned in the up/down direction (though the arrangement is not limited to such alignment in the up/down direction). Specifically, the center line  2144 C of power key  2144  is the same as the center line of energy-saving key  2146 . Further, again in the present modification, since power key  2144  and energy-saving key  2146  have the same size, edge line  2144 E of power key  2144  is the same as edge line of energy-saving key  2146 . 
     The planar arrangement of power key  2144 , energy-saving key  2146  and home key  2148  will be described. As shown in  FIG. 9 , these three hardware buttons (keys) are arranged such that the center line  2148 C of home key  2148  is positioned closer to the side of touch-panel display  130  than the center line  2144 C of power key  2144  (which is also the center line of energy-saving key  2146 ). Further, these three hardware buttons (keys) are arranged such that the edge line  2148 E of home key  2148  is positioned closer to the side of touch-panel display  130  than the edge line  2144 E of power key  2144  (which is also the edge line of energy-saving key  2146 ). The edge line  2148 E of home key  2148  indicates the position of the edge opposite to (away from) the touch panel display  130 , and edge line  2144 E of power key  2144  and energy-saving key  2146  indicates the position of the edge on the side of (closer to) touch-panel display  130 . 
     Though not limiting, as shown in  FIG. 9 , in the image forming apparatus, pilot lamp  2142  is arranged on the center line  2144 C of power key  2144  (which is also the center line of energy-saving key  2146 ). 
     As described above, in the image forming apparatus in accordance with the present modification, the home key for switching the display of touch-panel display to the home screen image allowing selection of an operation mode is provided to be integral with the touch-panel display and, therefore, the user can easily find the home key. 
     In the embodiment and modifications described above, that the home key is provided closest to the touch-panel among the hardware buttons has been described with reference to the positional relation of center lines or edge lines of hardware buttons. The position may not be defined by the center line or edge line, provided that the home key is substantially positioned closest to the touch-panel display. 
     The embodiments as have been described here are mere examples and should not be interpreted as restrictive. The scope of the present invention is determined by each of the claims with appropriate consideration of the written description of the embodiments and embraces modifications within the meaning of, and equivalent to, the languages in the claims.