Scroll controller

There is provided a scroll controller which solves a problem that in scrolling an image at coordinates specified by a pen or the like to specific coordinates (e.g., the center), it is unable in a display such as a liquid crystal display having a slow display reaction speed to grasp the state of movement when a scroll quantity (scroll speed) per unit time is fast. The scroll controller calculates a difference between prefixed coordinates and the coordinate position specified by a position specifying device and on the basis of the calculation result, controls so that not only stepwise scroll quantities are obtained, but also scroll quantities in starting and ending of the scroll are different from that in the other time of the scroll.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to a scroll controller capable of converting
 data into an image which can be visually displayed and visually displaying
 the image, which scroll controller may be suitably embodied in personal
 computers and small electronic apparatuses.
 2. Description of the Related Art
 Hitherto, as a so-called scroll control in a small electronic apparatus,
 there has been a technology of conducting a scroll operation by setting a
 moving direction and a moving quantity by points as described in Japanese
 Unexamined Patent Publication JP-A 9-69037 (1997) for example.
 FIGS. 13A and 13B are a diagrammatic view and a graph for explaining the
 related art scroll operation. An outer frame 83 in FIG. 13A denotes an
 edge of a scroll area of a display screen of a display device, i.e., a
 visual display area where an image scroll operation is carried out.
 A reference point 85 is set at the center of the scroll area. A specified
 point 130 is a point within the scroll area corresponding to a point which
 has been inputted and specified by an user of the electronic apparatus
 through a coordinate input device.
 When the specified point 130 is specified, a central processing unit
 scrolls a part of data image displayed on the display screen of the
 display device so that an image displayed at the position of the specified
 point 130 is displayed at the position of the reference point 85 via six
 relay points 131.
 That is, the image which has been displayed right under the point where the
 user has pressed the coordinate input device 13 is scrolled so as to be
 positioned at the center of the display device 12 step by step. The scroll
 is performed so as to switch images for example in this prior art example.
 A moving quantity of one step in scrolling the image is specified to be
 equal to a distance obtained by dividing the distance between the
 reference point 85 and the specified point 130 into seven equal parts for
 example. The image is switched and scrolled by 1/7 of the distance between
 the reference point 85 and the specified point 130 in the first step and
 then it is scrolled to the position of 2/7 of the distance between the
 reference point 85 and the specified point 130 in the second step. The
 image which has been displayed at the position of the specified point 130
 is displayed at the position of the reference point 85 by repeating the
 above-mentioned procedure by seven times. Accordingly, the greater the
 distance between the reference point 85 and the specified point 130, the
 greater the distance of one step where the image is scrolled becomes.
 The image is scrolled in the direction from the specified point 130 to the
 reference point 85 in the scroll operation of this prior art example. That
 is, when the point 130 is specified, the image is scrolled in the
 direction indicated by a vector 132, i.e., in the upper left direction, in
 this prior art example.
 FIG. 13B is a graph showing the relationship between a time and a speed in
 scrolling the image of this case. Assuming a time required for scrolling
 from the specified point 130 to the relay point 131a is t10 and the speed
 from the specified point 130 to the relay point 131a is s10, the moving
 distance of one step may be represented as "t10.times.s10".
 The moving distance between the respective remaining points may be
 represented as "t10.times.s10" in the same manner and the moving speed in
 each unit time from the specified point 130 to the reference point 85 is
 constant. Thus, the electronic apparatus 11 of this prior art example can
 scroll the image stepwise in any direction.
 However, the above-mentioned prior art technology has had a problem that
 because the scroll speed is all the same, it confuses the user because the
 image moves quickly to the specified position and the moving
 directionality cannot be get when a display device such as a liquid
 crystal display whose display processing speed is low is used.
 Further, the related art technology has another problem that it becomes
 difficult to confirm a scroll quantity as the scroll speed increases and
 that the scroll had to be released in order to confirm the scroll
 quantity.
 SUMMARY OF THE INVENTION
 Hence, a primary object of the invention is to provide a scroll controller
 capable of scrolling an image in an arbitrary direction when a pen is
 touched to an image and immediately separated therefrom, and starting and
 ending a scroll of an image with different scroll quantities from that of
 the other time of the scroll.
 Another object of the present invention is to provide a scroll controller
 capable of confirming a scroll quantity by changing an image moving speed
 in accordance to a moving distance of a tip of the pen when the tip of the
 pen is continuously touched to an image and by informing that an image at
 specified coordinates has been scrolled to a fixed coordinate position.
 The invention provides a scroll controller comprising a storage device for
 storing image information; a display device for displaying the image
 information stored in the memory device; a position specifying device for
 specifying the coordinate position of the image information displayed on
 the display device; a calculating device for calculating a difference
 between prefixed coordinates and the coordinate position specified by the
 position specifying device; a scroll quantity setting device for setting a
 scroll quantity per unit time on the basis of a calculation result of the
 calculating device; and a scroll control device for scrolling the image
 information on the basis of the scroll quantity set by the scroll quantity
 setting device.
 In the invention it is preferable that the scroll quantity setting device
 sets scrolling quantities so that a scroll starts and ends with different
 scrolling quantities from that of the other time of the scroll.
 In the invention it is preferable that when a plurality of scroll
 operations by the scroll control device are carried out consecutively, the
 scroll quantity setting device increments a scroll quantity per unit time
 operation by operation.
 As mentioned above, according to the invention, the scroll controller
 comprises the position specifying device, e.g., a so-called tablet. Then,
 an operator is allowed to scroll an image in any direction by touching a
 pen to the tablet and immediately separating the pen therefrom. Further,
 since the scroll controller is arranged so as to start and end the scroll
 operation with different scroll quantities from that of the other time,
 the operator can readily recognize the moving directionality. Still more,
 since the scroll quantity per unit time increases when the scroll
 operation is consecutively carried out a plurality of times, the scroll
 operation of a long distance may be performed in a short time.
 The invention provides a scroll controller comprising a storage device for
 storing image information; a display device for displaying the image
 information stored in the memory device; a position specifying device for
 specifying the coordinate position of the image information displayed on
 the display device; a calculating device for calculating a difference
 between prefixed coordinates and the coordinate position specified by the
 position specifying device; a scrolling device for scrolling the image
 information at the specified coordinate position to the fixed coordinate
 position based on the calculation result of the calculating device; and a
 notifying device for notifying at the point of time when the image at the
 specified coordinates is scrolled to the fixed coordinates by the
 scrolling device.
 As mentioned above, according to the invention the scroll controller
 comprises the position specifying device, e.g., a so-called tablet. In the
 case that the operator continuously touches the pen to the tablet, when
 the image at the specified coordinates is scrolled to the fixed coordinate
 position, the scroll controller notifies that the scroll has carried out
 to the fixed coordinate position. Thereby, the operator can recognize the
 state of move, regardless whether it is large or small, by repeating the
 scroll operation and the notifying process during when the tablet is being
 touched by the pen.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 Now referring to the drawings, preferred embodiments of the invention are
 described below.
 The present invention will be explained below in detail based on preferred
 embodiments thereof shown in the appended drawings. It is noted that the
 present invention is not confined to those embodiments.
 FIG. 1 is a perspective view showing an appearance of an electronic
 apparatus 11 equipped with a scroll controller of the invention. The
 electronic apparatus 11 is an apparatus so-called a personal digital
 assistant or an electronic pocketbook having functions of managing
 telephone numbers and schedules and of storing and editing inputted
 character strings.
 The electronic apparatus 11 comprises a display device 12 and a coordinate
 input device 13. The display device 12 may be realized by a liquid crystal
 display for example. The coordinate input device 13 is transparent and is
 disposed in contact on a display screen of the display device 12.
 The coordinate input device 13 detects two-dimensional coordinates of a
 point where a user touches the surface of the coordinate input device 13
 by a finger or a pen 15. The coordinate input device 13 is realized by a
 touch panel called a tablet. While there are various types of touch panels
 such as a resistance film type, an electrostatic capacity type, an optical
 type and an ultrasonic type touch panel in general, any type of touch
 panel may be used as the coordinate inputting section of the embodiments
 of the invention.
 Here, the structure of the resistance film type touch panel will be
 explained below. The resistance film type touch panel has two transparent
 electrode members formed by molding a transparent conductor thin film on a
 transparent glass or film. The touch panel is constructed by disposing the
 transparent electrode members so that the faces on which the conductor
 thin films are formed face to each other and by creating an insulating dot
 spacer on the face of one transparent electrode member on which the
 conductor thin film is formed to prevent the two transparent electrode
 members from contacting each other. When one point of such touch panel is
 pressed, the conductor thin films of the two transparent electrode members
 short. The pressed position may be detected by utilizing this
 short-circuit.
 Fixed keys 10 displayed on the both ends of the display device 12 are what
 frequently used fixed functions are displayed and printed by
 comprehensible marks on a film inserted between the coordinate input
 device 13 and the display device 12.
 The power source of the electronic apparatus 11 may be turned ON by
 touching the coordinate input device 13 in the state when it is off. A pen
 storage section 11b for storing the pen 15 for inputting coordinates on
 the coordinate input device 13 is provided on the side of a case 111of the
 electronic apparatus 11. A lid 11c connected to the case 111by a hinge is
 provided on the back of the case 111of the electronic apparatus 11. The
 lid 11c turns so as to cover the display device 12 and the coordinate
 input device 13, so that it plays a role of protecting the display device
 12 and the coordinate input device 13 in carrying the electronic apparatus
 11.
 FIG. 2 is a front view of the electronic apparatus 11 shown in FIG. 1. The
 electronic apparatus 11 has a mode key group 16 and a function key group
 17. The mode key group 16 and the function key group 17 are the fixed keys
 10 shown in FIG. 1.
 The mode key group 16 is a group of keys for switching and running
 functions which can be carried out by the electronic apparatus 11, such as
 the function for managing a telephone numbers and schedules and the
 function for inputting and editing character strings.
 The mode key group 16 includes a data processing mode key 20 which is a key
 for imaging, displaying and editing data.
 The function key group 17 is a group of keys for specifying an operation
 which can be executed in the state where a function selected by keying a
 key of the mode key group 16 is being run. The function key group 17
 includes a feed forward key 21 and a feed backward key 22 which are
 instruction keys for switching data displayed within the display device 12
 to other data, a menu key 23 which is an instruction key for displaying a
 menu screen for selecting and executing a plurality of processing
 functions, an interrupt key 25 which is an instruction key for
 interrupting a process being run, and a disconnect key 26 which is a key
 for turning off the power source of the electronic apparatus 11.
 FIG. 3 is a block diagram showing the electrical structure of the scroll
 controller 11 shown in FIG. 1. The electronic apparatus 11 comprises the
 display device 12, the coordinate input device 13, a position detecting
 section 31, a central processing unit 32, a display control section 33, an
 RTC 38, an input/output port 39, an external connection connector 41, a
 buzzer 42, memories 43 and 44 and a power source 60.
 When the user manipulates the coordinate input device 13 by pressing it for
 example, the position detecting section 31 detects coordinates of the
 position where the coordinate input device 13 is manipulated and outputs
 positional information to the central processing unit 32.
 The central processing unit 32 outputs data for displaying a display image
 on the display device 12 to the display control section 33. The display
 control section 33 controls the display device 12 in accordance to the
 output given from the central processing unit 32.
 The central processing unit 32 comprises a computing section 34, a storage
 section 35 and an input/output section 36. The computing section 34
 performs arithmetic operations based on the output given to the central
 processing unit 32. The storage section 35 includes an internal memory and
 registers for storing the data used in the arithmetic operation performed
 in the computing section 34 and the computed results.
 The input/output section 36 includes an input/output port and a buffer for
 receiving the output given to the central processing unit 32. The
 input/output port 39 exchanges data between another electronic apparatus
 connected via an external connector 41 and the central processing unit 32
 of the electronic apparatus 11. The input/output port 39 also controls the
 buzzer 42 provided in the electronic apparatus 11 in accordance to the
 output from the central processing unit 32.
 The central processing unit 32 reads data stored in the memories 43 and 44.
 The memory 43 comprises a data section 46 and a program section 47. Font
 data and graphic data for displaying characters on the display device 12
 and the other data such as a translation dictionary for translating
 hiragana characters inputted to input Japanese into kanji characters are
 stored in the data section 46. The "character" is a concept including
 hiragana characters, katakana characters, kanji characters, alphabets,
 numerals, symbols, icons and the like. A character string is an aggregate
 of a plurality of characters.
 A program for implementing processes of the function corresponding to each
 key of the above-mentioned mode key group 16, a program for controlling
 the operation of the electronic apparatus 11 and the like are stored in
 the program section 47. The memory 43 may be realized by a read only
 memory for example.
 The memory 44 comprises a buffer section 49, a flag section 50, a data
 section 51, a display position section 52 and a display buffer section 53
 and stores the output from the central processing unit 32. The memory 44
 may be realized by a random access memory.
 The buffer section 49 is used to store data temporarily in executing the
 program in the program section 47 of the memory 43. Similarly to that,
 flags used in executing the program in the program section 47 of the
 memory 43 are stored in the flag section 50. Data to be visually displayed
 on the display device 12 is stored in the data section 51 while having
 being developed into the mode which can be displayed on the display screen
 of the display device 12.
 Data indicative of that image data to be displayed on the display screen of
 the display device 12 as a display image belongs to which part of the data
 stored in the data section 51 is stored in the display position section
 52. The image data of the display image to be visually displayed on the
 display screen of the display device 12 is stored in the display buffer
 section 53.
 Electric power is supplied from the power source 60 to the central
 processing unit 32. The power source 60 is provided with a driving battery
 61, a backup battery 62 and a power circuit 63. The driving battery 61
 drives the whole electronic apparatus 11. The backup battery 62 holds the
 contents stored in the memory 44 and the storage section 35 of the central
 processing unit 32. The power circuit 63 performs a low battery check to
 detect exhaustion of the batteries 61 and 62.
 FIG. 4 shows a display image 71 displayed on the display device 12. When
 the user manipulates the data processing mode key 20 in the mode key group
 16, the inventive electronic apparatus 11 images part of data stored in
 the data section 51 of the memory 44 and visually displays on the display
 device 12 as shown in FIG. 4.
 The display image 71 is composed of a data display part 73 and a command
 display part 74. The data display part 73 is a part for displaying an
 image which has been imaged to visually display part of the data stored in
 the data section 51.
 The command display part 74 is a part for clearly expressing for the user
 that a data processing function is being implemented and for displaying
 images of buttons used in the processing function. For instance, "PHOTO
 MEMORY" is a comment indicative of that the data processing operation is
 being executed and does not change until when the data processing
 operation ends.
 Part 75 shows a title of data presently displayed. "NEW INPUT", "CORRECT",
 "SECRET", "LIST", and "ONE SUBJECT" are images of buttons 76 through 80
 for instructing processing operations to be implemented in the respective
 data processing functions.
 In the electronic apparatus 11 of the present embodiment, the buttons are
 constructed by combining the image drawn on the display screen of the
 display device and the coordinate input device 13 positioned right above
 the image when it is displayed. That is, it is determined that each button
 is manipulated and a processing operation corresponding to that button is
 executed when coordinates inputted by the coordinate input device 13
 specify the position corresponding to the position where each button
 within the image is drawn. So to speak, it is equivalent to that a partial
 area of the coordinate input device 13 sectioned by the image displayed on
 the display device 12 is used as an input device. When the coordinates of
 the sectional area are detected, a function represented by the image
 displayed on the display device 12 right under the sectional area is
 executed.
 Further, the original disposition of each button of the input device set by
 combining the display device 12 and the coordinate input device 13 may be
 readily changed just by changing a program which causes an inputted image
 to correspond with the display image. Accordingly, the display screen of
 the display device may be used in maximum by using the above-mentioned
 buttons as the input device in the electronic apparatus such as a small
 portable information terminal whose size is limited.
 Part of data stored in the data part 51 is imaged and displayed on the data
 display part 73. The data stored in the data section 51 is imaged in
 correspondence to an imaginary display area which is larger than the data
 display part 73. The image displayed in the data display part 73 is an
 image formed by cutting out a part of the imaginary image. Accordingly,
 there exists image corresponding to the data not displayed on the display
 device 12 at the periphery of four sides of the image in the data display
 part 73. A scroll operation is carried out to display the image of the
 data not displayed at the center of the data display part 73 at the center
 by specifying a point within the display screen corresponding to the data
 display part 73 in the present embodiment.
 The operation will be explained below with regard to first scroll control
 with reference to FIGS. 3 through 8. FIGS. 5A through 5H show changes of
 images to be displayed by the scroll operation. An outer frame 83 in FIGS.
 5A through 5H corresponds to a boundary line 73a of the area of the data
 display part 73 in FIG. 4 and denotes an edge of a scroll area 84 of the
 display screen of the display device 12 which is a visual display area
 where the image scroll operation is carried out.
 The display images shown in FIGS. 5A through 5H are displayed sequentially
 in this order. All of the two consecutive display images are displayed at
 equal time intervals. A graphic 80 containing {character pullout}
 positioned at the lower right part of a route map in FIG. 5A may be moved
 to the center by touching the graphic 80 by the pen 15 and then by
 separating it. The image at the touched position is started to be scrolled
 to the center by this manipulation.
 That is, when the user touches the graphic 80 by the pen as shown in FIG.
 5A, {character pullout} is scrolled in the direction of the center of the
 scroll area 84 slightly as shown in FIG. 5B. The graphic 80 is scrolled
 further in the direction of the center of the scroll area 84 slightly as
 shown in FIG. 5C.
 Then, as shown in FIG. 5D, it is scrolled in the direction of the center
 largely as compared to the distances between those in FIGS. 5A and 5B and
 in FIGS. 5B and 5C. It is scrolled to the state in FIG. 5F with the same
 rate.
 It is scrolled in the direction of the center slightly between the states
 in FIGS. 5F and 5G and FIGS. 5G and 5H similarly to those between FIGS. 5A
 and 5B and FIGS. 5B and 5C. The scroll operation ends when the graphic 80
 is positioned at the center of the scroll area 84 as shown in FIG. 5H.
 The fore-going scroll operation will be explained below in detail with
 reference to FIGS. 6 through 8. FIG. 6A is a diagrammatic view for
 explaining the scroll operation in the first embodiment.
 An outer frame 83 in FIG. 6A corresponds to the boundary line 73a of the
 area of the data display part 73 in FIG. 4 and denotes an edge of the
 scroll area 84 of the display screen of the display device 12 which is a
 visual display area where the image scroll operation is carried out.
 A reference point 85 is set in the scroll area 84. While the reference
 point 85 may be set at any position within the scroll area 84, assume here
 that the reference point 85 is set at the center of the scroll area 84. A
 specified point 86 is a point within the scroll area 84 corresponding to
 the point inputted and specified by the user of the electronic apparatus
 11 via the coordinate input device 13.
 When the user presses one point of the coordinate input device 13 provided
 over the display screen of the display device 12 by the pen 15, the point
 on the display screen of the display device 12 right under the pressed
 point is specified as the specified point.
 When the specified point 86 is specified, the central processing unit 32
 scrolls the data display part displayed on the display screen of the
 display device 12 so that the image displayed at the position of the
 specified point 86 is displayed at the position of the reference point 85
 via six relay points 88.
 That is, the image displayed right under the point where the user has
 pressed the coordinate input device 13 is scrolled so as to be positioned
 at the center of the display device 12 step by step. The scroll is carried
 out so as to switch the images stepwise for example in the present
 embodiment.
 The specified point 86 corresponds to the graphic 80 in FIG. 5A, each point
 of the relay points 88 corresponds to that in FIGS. 5B through 5G and the
 reference point 85 corresponds to that in FIG. 5H, respectively. The image
 is scrolled by switching the images so that the graphic 80 moves from the
 specified point 86 to the relay point 88a in the first step and is
 scrolled so that the graphic 80 moves from the relay point 88a to the
 relay point 88b in the second step. The image displayed at the position of
 the specified point 86 is displayed at the position of the reference point
 85 by repeating this operation by seven steps.
 The image is scrolled from the specified point 86 in the direction of the
 reference point 85 in the scroll operation of the present embodiment. That
 is, when the specified point 86 is specified, the image is scrolled in the
 direction indicated by a vector 92, i.e., in the upper left direction, in
 the present embodiment. However, the image may be scrolled not only in the
 direction of the vector 92 but also in any direction of up and down, right
 and left and oblique directions.
 When a command is issued to scroll up, down, right or left in the case that
 an upper, lower, right or left edge of the original data is displayed, it
 may be scrolled only within an extent where the original data exists.
 FIG. 6B is a graph showing the relationship between an image moving time
 and an image moving speed in scrolling the image as shown in FIGS. 5A
 through 5H. When it is assumed that a time required for moving from the
 specified point 86 to the relay point 88a is t1 and a speed per one step
 between the relay point 88b and the relay point 88f is s1 , moving
 distances from the specified point 86 to the relay point 88a and from the
 relay point 88g to the reference point 85 may be represented as
 "(t1.times.s1/2)/2=(t1.times.s1)/4", respectively, and moving distances
 from the relay point 88a to the relay point 88b and from the relay point
 88f to the relay point 88g may be represented as
 "(t1.times.s1)-(t1.times.s1)/4", respectively, respectively.
 A moving distance per step between the relay point 88b and the relay point
 88f may be represented as "t1.times.s1". The moving speed from the
 specified point 86 to the relay point 88b is accelerated, the moving speed
 per unit time from the relay point 88b to the relay point 88f is constant
 and the moving speed from the relay point 88f to the reference point 85 is
 decelerated as shown in the figures.
 Next, the relationship between the moving distance and the moving speed
 will be explained with reference to FIGS. 8A through 8D. FIG. 8A is a
 graph showing a pattern of a moving quantity for moving an image. The
 moving quantity is composed of a starting pattern, an intermediate pattern
 and an ending pattern as shown in FIG. 8A.
 The starting pattern represents the pattern of moving quantity when the
 speed is accelerated, the intermediate pattern represents the pattern of
 moving quantity when the speed is held at a constant speed and the ending
 pattern represents the pattern of moving quantity when the speed is
 decelerated. When the specified point is specified, the moving quantity is
 set by combining the above-mentioned three patterns in accordance to a
 distance between the reference point and the specified point. The starting
 pattern and the ending pattern are used preferentially in combining the
 three patterns. In concrete, the combination of the three patterns is
 determined by the distance from the specified point to the reference
 point, i.e., the relationship of magnitude between the scroll moving
 quantity and the reference moving quantity set by combining the starting
 and ending patterns.
 For instance, assume two cases when a point 86A and a point 86B are
 specified within the scroll area 84 as shown in FIG. 7A. The former point
 86A is closer to the reference point 85 than the latter point 86B. When
 the farther point 86B is specified among the two points, i.e., when the
 scroll moving quantity is equal and more than the reference moving
 quantity, the moving quantity is set to calculate a moving quantity of
 each scroll step by combining all of the above-mentioned three patterns as
 shown in FIG. 8B. When the point 86A which is closer to the reference
 point 85 among the two points is specified, i.e., when the scroll moving
 quantity is less than the reference moving quantity, the starting pattern
 and the ending pattern are combined at first as shown in FIG. 8C.
 When the starting pattern and the ending pattern overlap as shown in FIG.
 8D as a result by combining the starting pattern and the ending pattern, a
 pattern of moving quantity is set by calculating an acceleration which
 will eliminate the overlap of the starting pattern and the ending pattern
 as shown in FIG. 8D.
 The operation will be explained below with regard to a second scroll
 control with reference to FIGS. 7 and 9 through 11. The user may move an
 image at the position distance from the reference point 85 on the display
 device 12 by pressing the image in the direction where the image to be
 moved exists by the pen 15.
 The image pressed by the pen 15 scrolls to the position of the reference
 point 85 via two relay points. FIG. 7B is a graph showing the difference
 of moving speeds caused by the difference of moving distances. The
 difference of the moving speeds will be explained by exemplifying two
 cases when the specified point 86A closer to the reference point and the
 specified point 86B distant from the reference point are touched,
 respectively, as shown in FIG. 7A. That is, the images may be scrolled by
 taking an equal time in these two cases by increasing the acceleration in
 moving the image when the specified point 86B distant from the reference
 point is specified more than that when the specified point 86A closer to
 the reference point is specified as shown in the graph in FIG. 7B in which
 the horizontal axis represents the time.
 When it is detected that the image at the position pressed by the pen 15
 has been scrolled to the position of the reference point 85, the central
 processing unit 32 outputs a signal to cause the buzzer 42 to buzz. When
 the user keeps to press the pen 15 further, the image at the position
 pressed by the pen 15 at present is scrolled to the position of the
 reference point 85 via the two relay points and then the buzzer 42 buzzes.
 This is repeated until when the pen 15 is separated from the display
 device 12 or until reaching to the end of the corresponding imaginary
 image. One time of image scroll from the specified point to the reference
 point and the output of the buzzer sound are combined as one set and the
 moving speed is increased in every one set.
 The difference of the moving speeds caused by the difference of distances
 from the reference point 85 will be explained with reference to FIGS. 9A
 and 9B and FIGS. 10A and 10B, respectively.
 FIG. 9A is a diagrammatic view showing a scroll operation when the
 specified point 86B is fully separated from the reference point. When the
 user presses one point on the coordinate input device 13 provided over the
 display screen of the display device 12 by the pen 15, the point on the
 display screen of the display device 12 right under the pressed point is
 specified as the specified point 86B in FIG. 9A. When the specified point
 86B is specified, the central processing unit 32 calculates a distance
 between the specified point 86B and the reference point 85.
 The central processing unit 32 also scrolls the data display part displayed
 on the display screen of the display device 12 via two relay points 89 so
 that the image displayed at the position of the specified point 86B is
 displayed at the position of the reference point 85.
 That is, the image which has been displayed right under the pressed point
 of the coordinate input device 13 is scrolled step by step so as to be
 positioned at the center of the display device 12. It is specified such
 that the moving quantity of one step for scrolling the image is equal to a
 trisected distance of the distance between the reference point 85 and the
 specified point 86B.
 The second scroll operation is carried out so as to switch the images
 stepwise for example. The image is scrolled by switching the images so
 that the image moves from the specified point 86B to the relay point 89a
 in the first step and is scrolled so that the image moves from the relay
 point 89a to the relay point 89b in the second step. It is then scrolled
 from the relay point 89b to the reference point 85 in the third step.
 Thus, the image which has been displayed at the position of the specified
 point 86B is displayed at the position of the reference point 85. At this
 time, the buzzer 42 buzzes.
 When the user keeps to press the pen 15 further, the image at the position
 pressed by the pen 15 at present is scrolled to the position of the
 reference point 85 via the two relay points and then the buzzer 42 buzzes.
 This operation is repeated until when the pen 15 is separated from the
 display device 12 or until reaching to the end of the corresponding
 imaginary image. The operation until when the buzzer buzzes is set as one
 set and the moving speed is increased in every one set.
 The image is scrolled from the specified point 86B in the direction of the
 reference point 85 in the second scroll operation. That is, when the user
 specifies the specified point 86B, the image is scrolled in the direction
 indicated by a vector 93, i.e., in the left horizontal direction, in the
 present embodiment.
 However, the image may be scrolled not only in the direction of the vector
 93 but also in any direction of up and down, right and left and oblique
 directions. When the upper, lower, right or left edge of the original data
 is being displayed and when the user issues a command to scroll to the
 upper, lower, right or left direction, the image may be scrolled only
 within the extent where the original data exists.
 FIG. 9B is a graph showing the relationship between a time and a speed in
 scrolling the image by continuously touching by the pen 15. The
 acceleration in the scroll operation is determined in accordance to a
 moving distance. Because the specified point 86 B is fully separated from
 the reference point 85, the acceleration is large. The buzzer buzzes at
 points indicated by arrows indicating ends of the sets.
 Assuming a time required for scrolling the image by the first one set is t2
 and a speed at the first one set is s2, a moving distance at this time may
 be represented as "t2.times.s2". When a time required for scrolling the
 image by the next one set is t3 and a speed at this time is s3, a moving
 distance at this time may be represented as "t3.times.s3". When a time
 required for scrolling the image by the third one set is t4 and a speed at
 this time is s4, a moving distance at this time may be represented as
 "t4.times.s4".
 Then, as shown in FIG. 9B, the time t3 required for scrolling the image by
 the second one set is shorter than the time t2 required for scrolling the
 image by the first one set and the time t4 required for scrolling the
 image by the third one set is shorter than the time t3 required for
 scrolling the image by the second one set. That is, the time required for
 moving the image in the equal distance is shortened in every one set by
 touching the display screen continuously by the pen 15.
 The speed s3 in scrolling the image by the second one set is faster than
 the speed s2 in scrolling by the first one set and the speed s4 in
 scrolling by the third one set is faster than the speed s3 in scrolling by
 the second one set, respectively. The speed in the equal distance
 increases in every one set by touching the display screen continuously by
 the pen 15.
 Because the maximum value of the moving speed is determined, no speed is
 added further from the fifth set. The buzzer buzzes every time when the
 move of one set ends.
 FIG. 10A is a diagrammatic view showing a scroll operation when the
 specified point 86A is close to the reference point. When the user presses
 one point on the coordinate input device 13 provided over the display
 screen of the display device 12 by the pen 15, the point on the display
 screen of the display device 12 right under the pressed point is specified
 as the specified point 86A in FIG. 10A. When the specified point 86A is
 specified, the central processing unit 32 calculates a distance between
 the specified point 86A and the reference point 85.
 The central processing unit 32 also scrolls the data display part displayed
 on the display screen of the display device 12 via two relay points 90 so
 that the image displayed at the position of the specified point 86A is
 displayed at the position of the reference point 85.
 That is, the image which has been displayed right under the pressed point
 of the coordinate input device 13 is scrolled step by step so as to be
 positioned at the center of the display device 12. It is specified so that
 the moving quantity of one step for scrolling the image is equal to a
 trisected distance of the distance between the reference point 85 and the
 specified point 86A.
 The scroll operation of the present embodiment is carried out so as to
 switch the images step wise for example. The image is scrolled by
 switching the images; so that the image moves from the specified point 86A
 to the relay point 90a in the first step and is scrolled so that the image
 moves from the relay point 90a to the relay point 90b in the second step.
 It is then scrolled from the relay point 90b to the reference point 85 in
 the third step. Thus, the image which has been displayed at the position
 of the specified point 86A is displayed at the position of the reference
 point 85. At this time, the buzzer 42 buzzes.
 When the user keeps to press the pen 15 further, the image at the position
 pressed by the pen 15 at present is scrolled to the position of the
 reference point 85 via the two relay points and then the buzzer 42 buzzes.
 This operation is repeated until when the pen 15 is separated from the
 display device 12 or until reaching to the end of the corresponding
 imaginary image. The operation until when the buzzer buzzes is set as one
 set and the moving speed is increased in every one set.
 The image is scrolled from the specified point 86A in the direction of the
 reference point 85 in the scroll operation of the present embodiment. That
 is, when the user specifies the specified point 86A, the image is scrolled
 in the direction indicated by a vector 94, i.e., in the left horizontal
 direction, in the present embodiment. The image may be scrolled not only
 in the direction of the vector 94 but also in any direction of up and
 down, right and left and oblique directions. When the upper, lower, right
 or left edge of the original data is being displayed and when the user
 issues a command to scroll to the upper, lower, right or left direction,
 the image may be scrolled only within the extent where the original data
 exists.
 FIG. 10B is a graph showing the relationship between a time and a speed in
 scrolling the image by continuously touching by the pen 15. The
 acceleration in the scroll operation is determined in accordance to a
 moving distance. Because the specified point 86 A is close to the
 reference point 85, the acceleration is small. The buzzer buzzes at points
 indicated by arrows indicating ends of the sets.
 Assuming a time required for scrolling the image by the first one set is t7
 and a speed at the first one set is s7, a moving distance at this time may
 be represented as "t7.times.s7". When a time required for scrolling by the
 next one set is t8 and a speed at this time is s8, a moving distance at
 this time may be represented as "t8.times.s8". When a time required for
 scrolling by the third one set is t9 and a speed at this time is s9, a
 moving distance at this time may be represented as "t9.times.s9".
 Then, as shown in the figure, the time t8 required for scrolling the image
 by the second one set is shorter than the time t7 required for scrolling
 by the first one set and the time t9 required for scrolling by the third
 one set is shorter than the time t8 required for scrolling by the second
 one set. That is, the time required for moving the image in the equal
 distance is shortened in every one set by touching the display screen
 continuously by the pen 15.
 The speed s8 in scrolling the image by the second one set is faster than
 the speed s7 in scrolling by the first one set and the speed s9 in
 scrolling by the third one set is faster than the speed s8 in scrolling by
 the second one set, respectively. The speed in the equal distance
 increases in every one set.
 Because the maximum value of the moving speed is determined, no speed is
 added further from the fifth set. The buzzer buzzes every time when the
 move of one set ends.
 It is then apparent by comparing FIGS. 9B and 10B described above that the
 difference between the moving speeds of two consecutive steps in scrolling
 the image of the case when the point 86B which is distant from the
 reference point 85 is specified, i.e., the case of FIG. 9B, is greater
 than the difference between the moving speeds of two consecutive steps in
 scrolling the image of the case when the point 86A which is closer to the
 reference point 85 is specified, i.e., the case of FIG. 10B. That is, the
 increment of the moving speed, i.e., the acceleration, is greater in the
 latter than that of the former.
 FIG. 11 is a diagram showing the relationship between an imaginary image
 120 into which the data stored in the data section 51 is all imaged and
 the scroll area 84 on the display screen of the display device 12. Assume
 here that the data stored in the data section 51 is image data
 representing a route map.
 The above-mentioned scroll area 84 has a size capable of disposing an image
 of m dots in the X direction, i.e., in the horizontal direction, and n
 dots in the Y direction, i.e., in the vertical direction, in a matrix
 while leaving a predetermined gap between adjacent images per each image.
 That is, it can display each image in a matrix of (n.times.m).
 The imaginary image 120 displays each image in a matrix of (N.times.M). An
 image of data which can be displayed in the scroll area 84 is equivalent
 to what a part of the imaginary image 120 is cut out. Regions 84a through
 84d represent data portions within the imaginary image 120 which are
 displayed in the scroll area 84.
 That is, when the region 84a is displayed in the scroll area 84 at first,
 it means that the region 84a of the imaginary image 120 is cut out and is
 displayed on the display device 12. When the user instructs to scroll the
 image in the lower right direction at this time, the region to be cut out
 of the imaginary image 120 is changed by a number of moved dots, thus
 cutting out and displaying the region 84b on the display device 12. The
 data part to be displayed in the scroll area 84 may be any part other than
 that region.
 The first and second scroll control operations described above will be
 explained below with reference to a flowchart in FIG. 12.
 At first, the user displays information to which the user wishes to make
 reference on the display device 12 in STEP 1. In STEP 2, the process is
 held until when coordinates are inputted to the coordinate input device 13
 by the pen 15.
 When coordinates are inputted, it is discriminated whether or not the
 inputted coordinates exist in the scroll area 84 in STEP 3. When the
 coordinates have been inputted to the outside of the scroll area 84, a
 process corresponding to the other inputted position is implemented. When
 the coordinate has been inputted in the scroll area 84, the inputted
 coordinates are taken in and are stored in the data section 51 of the
 memory 44 in STEP 4.
 Then, a distance thereof from the center of the scroll area 84 in the
 X-axis direction is calculated in STEP 5 by comparing a value on the
 X-axis of the center coordinate of the scroll area 84 stored in advance
 and a value on the X-axis of the inputted coordinates taken in STEP 4.
 A distance thereof from the center of the scroll area 84 in the Y-axis
 direction is calculated in STEP 6 by comparing a value on the Y-axis of
 the center coordinate of the scroll area 84 stored in advance and a value
 on the Y-axis of the inputted coordinates taken in STEP 4.
 It is then discriminated whether or not the user is continuously touching
 the coordinate input device 13 by the pen 15 in STEP 7. When the user is
 not continuously touching the coordinate input device 13 by the pen 15, it
 is discriminated whether or not an image exists at the destination of the
 scroll within the imaginary image 120 as information to be moved in STEP
 8. When there is no information to be moved, a quantity which can be moved
 from the position of the region presently cut out of the imaginary image
 120 is set in STEP 9.
 It is then discriminated whether or not the moving quantity is longer than
 the starting and ending patterns shown in FIG. 8 in STEP 10. When the
 moving quantity is shorter than the starting and ending patterns shown in
 FIG. 8, a speed pattern is calculated from the starting and ending
 patterns in STEP 11. When the moving quantity is longer than the starting
 and ending patterns shown in FIG. 8, a speed pattern is calculated from
 the starting, intermediate and ending patterns in STEP 12. Then, the
 information displayed on the display device 12 is scrolled by using the
 calculated speed pattern in STEP 13.
 When the user is continuously touching the coordinate input device 13 by
 the pen 15 as a result of discrimination in STEP 7, an acceleration A is
 set in STEP 14 in accordance to the distance from the reference point 85
 obtained from the distances on the X- and Y-axes obtained in STEPs 5 and
 6.
 In STEP 15, the acceleration A set in STEP 14 is added to an acceleration B
 which is an initial value of an acceleration to set a new initial value B
 and the scroll quantity is set in accordance to the acceleration B. In
 STEP 16, it is discriminated whether or not there exists an image at the
 destination of the scroll within the imaginary image 120 as information to
 be moved. When there is no information to be moved, a quantity which can
 be moved from the position of the region presently cut out of the
 imaginary image 120 is set in STEP 17.
 In STEP 18, the information displayed on the display device 12 is scrolled
 by the quantity set in STEP 15 or in STEP 17. Then, it is discriminated
 whether or not one set of scroll has been completed in STEP 19.
 When one set of scroll has not been completed, the process returns to STEP
 16 and the processes from STEP 16 to STEP 19 are repeated until when one
 set of scroll is completed. When one set of scroll has been completed, the
 buzzer 42 clicks in STEP 20. Then, it is discriminated whether or not the
 user is continuously touching the coordinate input device 13 by the pen 15
 in STEP 21. When the user is not continuously touching the coordinate
 input device 13 by the pen 15, the process ends.
 When the user is continuously touching the coordinate input device 13 by
 the pen 15, the process returns to STEP 15 and the processes from STEP 15
 to STEP 21 are repeated until when the user separates the pen 15 from the
 display device 12. It is noted that a maximum value is set for the value
 of the acceleration B in STEP 15 in accordance to the value of the
 acceleration A, so that the value of B will not exceed that value. The
 scroll operation has been explained above with reference to the flowchart.
 It is noted that the variation of the scroll quantity has been explained by
 exemplifying the distances for moving images in a fixed time in the
 present embodiment, times for moving images in a fixed quantity may be
 used as the variation of the scroll quantity. Further, the present
 embodiment has been explained by using the pen as the coordinate inputting
 device, other pointing devices such as a mouse may be used.
 An image may be scrolled in an arbitrary direction by the above-mentioned
 processes in the electronic apparatus 11 by touching the coordinate input
 device 13 by the pen 15 and by separating it right away and the scroll
 operation may be started and ended with different scroll quantities from
 that in the other time of the scroll. Further, when the user continuously
 touches the coordinate input device 13 by the pen 15 and when an image at
 the specified coordinate is scrolled to the fixed coordinate position, the
 electronic apparatus 11 can inform of that and repeat the scroll operation
 and the informing process until when the pen 15 is separated from the
 coordinate input device 13.
 The invention may be embodied in other specific forms without departing
 from the spirit or essential characteristics thereof. The present
 embodiments are therefore to be considered in all respects as illustrative
 and not restrictive, the scope of the invention being indicated by the
 appended claims rather than by the foregoing description and all changes
 which come within the meaning and the range of equivalency of the claims
 are therefore intended to be embraced therein.