FR2792744A1 - Electronic document display unit with central electronic unit/memory interfacing display screens and allowing different display screen configurations and page jumping user markers. - Google Patents

Abstract

The electronic document display unit has a central electronic unit (5) with a memory (7,9) and connected to a display screen (3). There is a command interface (4). The memory has identification codes corresponding to different document configuration displays for the display screen. The central electronic unit allows jumping between different pages using electronic markers.

Description

Electronic device, data carrier, download process,

  software and method for visualization

of documents.

  The present invention relates to electronic devices, data carriers, downloading methods, software and methods for viewing.

of documents.

  More particularly, the invention relates to an electronic document viewing device, comprising a central electronic unit which includes a memory and which is connected to a display screen and to a control interface, the memory of the central unit containing at least a document in digital form which is intended to be presented on the screen and which comprises alphanumeric characters, this document being constituted

  mainly by frozen information.

  Document US-A-5 802 516 describes an example of

device of this type.

  The object of the present invention is in particular to allow the same document to be easily used in several display configurations, in particular: - to allow the document to be easily and instantly adapted to the characteristics of the screen used, in particular when the initial installation of the document in the electronic device, - and to allow a user to adapt the type of characters presented on the screen in particular according to his visual capacities or his comfort of use, this adjustment having to be carried out without requiring too much computer processing time to determine the new layout of the document presented on the screen. In conventional word processing software, when changing the font (when the software in question is used

  common, to type texts on a micro-

  computer), the entire layout of the document is gradually recalculated from the first page. This operating mode is possible for short documents of a few pages, but it is impractical, because too slow, for texts of several hundred pages such as are commonly found in electronic books or

  similar document viewing devices.

  In addition, the layout calculated automatically by conventional word processing software when changing the type of characters is generally of poor quality compared to the layout of a book.

printed on paper.

  In particular, the positions of page breaks and the hyphenation thus determined are generally not satisfactory, as are the positions and sizes of the illustrations on each page (when the document in question includes illustrations made up of

  photographs, drawings, formulas or others).

  To obtain the desired result, according to the invention, a device of the kind in question is characterized: - in that the document contains layout marks not visible on the screen which each include at least one corresponding identification code to a display configuration representative of the way the document is presented on the screen, the layout marks including at least page break marks which subdivide the document into pages and the identification codes understood by the different layout marks corresponding to several display configurations which themselves correspond to several screen layouts, - in that the memory contains at least one identification code corresponding to an active display configuration , with which the document must be presented on the screen, - and in that the electronic central unit is adapted to lay out the document using the marks d e layout which correspond to the active display configuration and to present the document on the screen according to said active display configuration with a page break for each page jump mark corresponding to said active display configuration, the pages delimited by the page breaks which correspond to the active display configuration being such that each of these pages appears entirely on the screen (possibly after a slight homothety, as explained below) when it is displayed with the

active display configuration.

  In a preferred embodiment, the memory contains characteristic data defining several possible types of characters, corresponding to several layouts on the screen, the command interface being adapted to allow a user to choose a type of character from the different possible types, these types of characters being divided into several groups of types of characters each comprising: - either a single type of characters, - or several types of characters of similar sizes, the display configuration which corresponds to each reference mark of layout comprising at least one group of character types, and the identification code of the active display configuration corresponding at least to the group of character types, known as the active group, to which the

  type of characters chosen by the user.

  It will be noted that the different "types of characters" mentioned above can correspond respectively: - to different fonts, and / or to different font sizes, - and / or to different attributes of the characters, such as bold, italics, etc. In this embodiment, the user of the electronic book can select the type of characters presented on the screen, after which the layout on the screen is changed almost instantly without the electronic central unit having to recalculate the position. page breaks, which would be an extremely slow operation for a long document and which would give a layout of

bad quality.

  In other preferred embodiments of the invention, it is possible optionally to have recourse to one and / or the other of the following provisions: the page break marks each include a code which represents the number corresponding page: 15. either to a page located immediately before the page break mark, when said page break mark corresponds to the active group, or to a page located immediately after the page break mark, when said page mark page break corresponds to the active group; - at least one of the groups of character types corresponding to the page break marks includes several types of characters of similar sizes, the page break marks which correspond to this group of character types being positioned in the document so that the different pages of the document delimited by these page break marks are fully visible on the screen for all the types of characters belonging to said group of character types when this group of character types is the active group; - at least one of the groups of character types corresponding to the page break marks includes several types of characters of similar sizes, the page break marks which correspond to this group of character types being positioned in the document so that the different pages of the document delimited by these page break marks are fully visible on the screen for all the types of characters belonging to said group of character types when said group of character types is the active group, after an adjustment of size of each page by homothety, with a coefficient of homothety which is specific to each type of characters, and the central unit being provided to adapt the size of each page when displaying this page on the screen by applying to said page a homothety with said coefficient of homothety; the central processing unit is adapted to automatically determine a coefficient of uniformity specific to a page and to a type of characters, when this page is displayed with the type of characters considered; - when the user chooses a new type of characters when an initial page was already displayed on the screen before resetting, the central unit is adapted to display on the screen a new page, comprising at least part from the initial page; the central unit is adapted to receive from the user, via the command interface, information making it possible to determine said part of the initial page which is included in the new page displayed on the screen after resetting document page; - Said part of the initial page which is included in the new page displayed on the screen after resetting the document, is a predetermined part of said initial page; - The central unit is adapted to present at least one visual signal highlighting said part of the initial page which is included in the new page displayed on the screen after resetting the document; the central unit is adapted to memorize in a permanent internal memory the last type of characters chosen by the user; the central unit is adapted to present on the screen indications relating to an original layout, corresponding to a predetermined type of characters, whatever the type of characters chosen by the user; the document also includes illustration marks corresponding to illustrations inserted in the text, these illustration marks being not visible on the screen and each comprising: at least one identification code corresponding to a display configuration , at least one code representative of the corresponding illustration, and coded position and / or size information, the electronic central unit being adapted to present the document on the screen with each illustration positioned and / or sized on the page corresponding as a function of said coded position and / or size information contained in the illustration mark of said illustration corresponding to the active configuration; the illustration marks further include coded information for the visual presentation of the illustrations, this coded information being representative of optical characteristics of each point belonging to the illustration; - The device constitutes an electronic book which is in the form of a portable box; the identification code of each display configuration corresponds to at least one screen characteristic specific to the display screen; said screen characteristic is a screen size; - the memory contains characteristics defining several possible types of characters, corresponding to several layouts on the screen, the command interface being adapted to allow a user to choose a type of characters from the different possible types, these types of characters being divided into several groups of types of characters each comprising: either a single type of characters, or several types of characters of neighboring sizes, each display configuration corresponding to a combination of at least one screen characteristic and d '' at least one group of character types, and the identification code of the active display configuration corresponding to the combination of the screen characteristic corresponding to the display screen of the device and of the group of character types to which

  belongs to the type of characters chosen by the user.

  Furthermore, the subject of the invention is also a data carrier for an electronic document viewing device as defined above, comprising an interface adapted to communicate with said data carrier, this data carrier having in memory at least a document in digital form which is intended to be presented on the screen of the electronic book and which comprises alphanumeric characters, this document consisting mainly of frozen information and said document containing layout marks not visible on the screen which each comprise at least one identification code corresponding to a display configuration, these layout marks corresponding to several display configurations which themselves correspond to several screen layouts, and said marks layout including at least

page break marks.

  The subject of the invention is also a method of downloading comprising at least one step consisting in downloading into the memory of an electronic document viewing device, at least one document in digital form which is intended to be presented on the screen and which includes alphanumeric characters, this document consisting mainly of frozen information, and said document containing layout marks not visible on the screen which each include at least one identification code corresponding to a group of character types , these layout marks corresponding to several display configurations which themselves correspond to several screen layouts, and said layout marks including at least

page break marks.

  A subject of the invention is also software comprising at least one data file that can be loaded into the memory of an electronic document viewing device as defined above, this data file comprising a document in digital form which is intended for be presented on the screen of the electronic book and which includes alphanumeric characters, this document consisting mainly of frozen information and said document containing layout marks not visible on the screen which each include at least one code identification corresponding to a display configuration, these layout marks corresponding to several display configurations which themselves correspond to several screen layouts, and said layout marks including at least

page break marks.

  Finally, the invention also relates to a method for viewing a document stored in digital form, by means of an electronic document viewing device which comprises an electronic central unit including a memory and connected to a viewing screen and to a command interface, the document being intended to be presented on the screen and comprising alphanumeric characters, and this document consisting mainly of frozen information, said document containing layout marks not visible on the screen which each comprise at least one identification code corresponding to a display configuration representative of the way in which the document is presented on the screen, the layout marks including at least page break marks which subdivide the document into pages, and the identification codes understood by the different layout marks corresponding to several co display configurations which itself correspond to several layouts on the screen, the method comprising the following steps: a / determining the identification code of an active display configuration, with which the document must be presented on the screen, b / lay out the document using the layout marks having an identification code which corresponds to the identification code of the active display configuration and present the document on the screen according to said active display configuration with a page break for each page break marker corresponding to said active display configuration, the pages delimited by the page breaks which correspond to the active display configuration being such that each of these pages appears entirely on the screen when

  is displayed with the active display configuration.

  In preferred embodiments of this display method, one and / or the other of the following arrangements can optionally be used: - the different display configurations include different types of characters grouped into several groups of character types each comprising at least one type of character, step a / comprising the following sub-steps: choosing a character type, * determining an identification code corresponding to the group of character types to which the type of characters selected, and store this identification code in the memory as identification code of the active display configuration; - the different display configurations correspond to several screen characteristics, step a / comprising the following sub-steps: choose a type of characters, * determine an identification code relating to the screen characteristic corresponding to l display screen of the electronic document presentation device, and memorizing in the memory this identification code as identification code of the active display configuration; the different display configurations correspond to several screen characteristics and to several types of characters grouped into several groups of types of characters each comprising at least

  a type of characters, step a / comprising the sub-

  following steps: * determine a first identification code relating to the screen characteristic which corresponds to the display screen of the electronic document presentation device, * memorize in the memory the identification code corresponding to this characteristic d 'screen, * choose a type of characters, determine a second identification code corresponding to the group of character types to which the chosen type of characters belongs, * store in memory this second identification code, determine and store in memory the identification code of the active display configuration, It corresponding to said first and second identification codes. Other features and benefits of

  the invention will appear during the description

  following of one of its embodiments, given as

  non-limiting example, with reference to the accompanying drawings.

  In the drawings: - Figure 1 is a schematic view of an electronic book according to an embodiment of the invention, - and Figure 2 is a partial block diagram of the

Figure 1 eBook.

  In the different figures, the same references

  denote identical or similar elements.

  FIG. 1 represents an electronic device 1 for viewing documents or electronic book, in the form of a portable portable unit 2, the front face of which is mainly constituted by a viewing screen 3 associated with an interface for

  command 4, in this case a simplified keyboard.

  This simplified keyboard 4 can for example comprise four buttons: - a first button 4a making it possible to bring up a menu on the screen, - second and third buttons 4b, 4c in the form of arrows which allow for example to select options in the menus appearing on the screen and which allow in current use to change the page presented on the screen, - and a fourth 4d button allowing to validate the options of the menus which are selected by means of the

arrows 4b, 4c.

  Of course, other control interfaces could be used, in place of or in addition to the simplified keyboard 4, for example a voice control, a rotary ball control ("track ball"), a tactile control, an "electronic pencil". "whose position of the tip on the screen 3 can be identified by the electronic book, etc. In addition, the box 2 may advantageously include a reader 8 capable of reading an external data medium, for example a standard memory card

PCMIA.

  As shown very diagrammatically in FIG. 2, the box 2 contains an electronic central unit 5 which is connected to the screen 3 and to the control interface 4, and which includes: - logic processing means 6 such as at at least one microprocessor MP, - storage means (hereinafter simply referred to as "the memory of the central unit") comprising at least: an internal memory (MEM), * and advantageously the memory card 9 associated with the interface 8 (INT.) Mentioned above, or any other external memory, and possibly a communication interface 10 (COM.), For example a serial or parallel port, a radio receiver, etc. The internal memory 7 of the central unit or the memory card 9 contains at least one data file comprising a document in digital form (originally contained in memory 7 or 9, or downloaded via the interface 10 via the Internet, by radio, by infrared link, or by any other means of communication) which is subdivided into pages intended to each occupy the entire screen 3 when they are displayed, this document comprising: - text, that is to say alphanumeric characters, - and illustrations (photographs, drawings, tables, mathematical or chemical formulas, etc.) including

  at least some are inserted in the text.

  The information contained in this document is mainly frozen and arranged in a predetermined way, with the exception of certain areas of each page, for example the margins or the top or bottom of the page, which may be the subject of annotations by the part when the control interface allows fairly easy data entry or when the electronic book can be connected by wire or wirelessly with an external device such as a microcomputer or simply

a full keyboard.

  Furthermore, in a manner known per se, the user can also place in certain locations of the document "bookmarks" making it possible to immediately find these locations during a subsequent use of the electronic book. To allow the user of electronic book 1 to adapt the display configuration, and in particular the type of characters presented on the screen (font, size of characters within the same font, attributes of characters such as bold, italic, etc.), memory 7 contains characteristics defining several possible types of characters, corresponding to several layouts to

the screen.

  These different types of characters are grouped into a certain number of groups, for example 10 groups each comprising one or more types of characters of similar sizes corresponding to the same layout.

the screen.

  The user can choose a type of character from the different possible types by means of the command interface, for example by selecting and validating a font with its size and its presentation attributes, in a drop-down menu that the we display on the screen using the buttons 4a-4d, as

explained above.

  In addition, the document contains in advance layout marks including in particular prepositioned page breaks, not visible on the screen, which each include: - an identification code corresponding to one of the groups of types of characters, - and a code which represents the page number corresponding for example to the page located immediately before the page break mark (or possibly to the page located immediately after the page break mark), when the type of characters chosen by the user belongs to group of character types, said group

  active, corresponding to said page break marker.

  Thus, when the user chooses a new type of characters, the microprocessor 6: - reshapes the document using the page jump marks which correspond to the active group, - and presents the document on screen 3 with the type of characters chosen and with a page break for each page break marker corresponding to the active group, each page thus delimited being then adapted to be fully visible on the screen when it is displayed. This operation is almost instantaneous, because the page break marks are positioned in advance in the document, and they already contain the numbers of

  page corresponding to the different possible layouts.

  In addition, the new layout of the document is optimal, since determined in advance by the editor of the

  document and not calculated automatically.

  It will be noted that, when a group of character types comprises several types of characters of similar sizes, the page break marks corresponding to this group of character types are positioned in the document so that the different pages of the document delimited by these page break marks are fully visible on the screen for all the types of characters belonging to this group of types of characters, if necessary after an adaptation of size of each page by a slight homothety, with a coefficient of homothety which is specific to each page and to each type

of characters.

  This coefficient of homothety is for example between 0.95 and 1.05, and it is either predetermined and assigned to each type of characters, or determined by the microprocessor 6 during the display of each page so as to match exactly the page displayed with

screen size.

  In addition, the document also includes, for each illustration, marks of illustrations not visible on the screen which each include: an identification code corresponding to one of the groups of types of characters, - a code representative of the corresponding illustration, for example a link code referring to a data file external to the document, this file containing the illustration, - and coded position and / or size information in the page, for example the abscissa and l ordinate of the point located at the top left of the illustration and the size of the illustration on the abscissa and on the ordinate (or a coefficient of homothety compared to an initial size) in a coordinate system representative of the

  different possible positions on the page.

  It will be noted that, the number of possible types of characters being finite, the size of the illustration within the screen page can only take a finite number of

discrete values.

  When the user chooses a new type of character, the microprocessor 6 presents each page of the document on the screen 3 with each illustration positioned and / or sized on the corresponding page, as a function of said coded position and size information contained in the illustration mark of said illustration corresponding to the group of characters to which the type of characters chosen belongs. Furthermore, the illustration marks may contain not only coded position and / or size information, but also coded information for the visual presentation of the illustration, for example relating to the palette of colors used, the brightness, the contrast, etc., or other optical characteristic of each point of the illustration, these parameters possibly being influenced by the choice of a type of characters by the user or possibly by

  a setting offered to the user.

  It will be noted that the same illustration, that is to say the same image, can if necessary be stored with different display characteristics (size, color, etc.) in several data files external to the document considered. In this case, the illustration marks corresponding to the same illustration will contain a code representative of said illustration which will be different from one illustration mark to another, depending on the group.

  corresponding character types.

  Finally, when the user chooses a new type of characters when an initial page was already displayed on the screen 3 before resetting, the microprocessor 6 displays on the screen a new page, comprising at least part of the initial page: it can be a predetermined part of the initial page, for example the start of the initial page, or a part of the initial page determined by the user by means of the command interface ( for example, a particular word

from the initial page).

  In addition, said predetermined part of the initial page or the part of the initial page determined by the user are preferably highlighted on the screen after resetting, for example by displaying a colored background at this level. part of the page, or

  again by displaying a moving symbol, or whatever.

  Advantageously, the central unit 5 always keeps in memory the original layout of the document 16 presented on the screen (that is to say the default layout chosen initially by the editor) and displays on screen 3, for example in the margin of the document, the indications making it possible to locate the part of the text which is displayed with the type of characters chosen by the user, in the original version of the document. For example, the central processing unit 5 can display, in the margin of the document, in the position which corresponds to the start of each page in the original layout: - the page number in the original layout, - and where appropriate the delimitation of this start

  page, represented for example by a dotted line.

  These provisions allow two users, reading the same document with different layouts on two e-books, to conveniently refer to

the same passage of the document.

  In addition, the layout marks do not necessarily include only page break marks, but may also include marks indicating line breaks, marks referring to another page of the document and making it possible to display at the screen refers to said other page in the layout corresponding to the type of characters chosen by the user, etc. Advantageously, the last type of character chosen by the user is stored in the internal memory 7 of the central unit 5, which is permanent, so that, each time the electronic book 1 is put into service, the document is displayed on the screen. screen with the layout corresponding to the last type of characters chosen by the user. Note that the page break and illustration marks can be determined either entirely by the document editor, or partly automatically: in this case, from a layout produced by the editor for a single type of characters, a computer program automatically determines the layout corresponding to each group of types of characters, according to predetermined presentation criteria, then the editor eventually refines this automatic layout. Of course, the invention is not limited to the mode

  particular embodiment which has just been described.

  In particular: - the electronic document viewing device could not be in the form of a portable box with a simplified keyboard such as that

  shown in Figure 1, but in the form of a micro-

  conventional computer, portable or not, - the different display configurations corresponding to the layout guides positioned in advance in the document could correspond not to groups of character types, but to screen characteristics specific to the display screen 3, in particular the size or the resolution of the screen: in this case, the layout marks which are used to lay out the document on the screen are those having a corresponding identification code an identification code previously memorized and representative of the characteristics of the display screen 3, - and the layout marks could correspond both to groups of types of characters and to screen characteristics, in which case the layout marks used to lay out the document on the screen would be those corresponding to the combination of the characteristics of the display screen 3 and of the typ e

  of characters chosen by the user.

  A particular example will make it clear what

last operating mode.

  In this particular example, each document is adapted to be presented: - on several electronic display devices, comprising for example standardized screens of size 6 '' or size 8 '' or size 10 '', - and using the '' one or other of the following groups of fonts: group 1: Times New Roman 10 or Arial 9, group 2: Times New Roman 14 or Arial 13, * group 3: Times New Roman 18 or Arial 16,

  15. group 4: Times New Roman 24 or Arial 22.

  As already explained above, the fonts belonging to the same group of fonts correspond to similar character sizes when displayed on the screen, and therefore to the same layout of the text when it is displayed on the screen. , each page determined by this layout being adapted to be fully visible on the screen of the document viewing device, possibly after a slight

  homothety as already explained above.

  The table below summarizes the different possible combinations of screen sizes and groups of

fonts.

  Font groups 6 '' 8 '' 10 '' Group 1: Times New Roman 10 C3 C2 Ci Arial 9 Group 2: Times New Roman 14 C4 C3 C2 Arial 13 Group 3: Times New Roman 18 C5 C4 C3 Arial 26 Group 4: Times New Roman 24 C6 C5 C4 Arial 22 As indicated in the table above, each combination of a screen size and a group of fonts corresponds to a code, respectively Cl to C6 As explained previously, the digital document contains layout marks each comprising one of the aforementioned identification codes C1-C6, these layout marks comprising in particular page jump marks which are adapted so that each page that they can be displayed in full on the screen with any of the fonts corresponding to

this identification code C1-C6.

  Note that the same C1-C6 identification code, and therefore the same layout mark, can correspond to several combinations of screen sizes and groups of

  fonts. For example, in the table below

  above, the layout marks corresponding to the identification code C3 are used both for the "Times New Roman 14" font with an 8 "screen, and for the" Arial 9 "font, from smaller

  size, combined with a smaller 6 '' screen.

  When the digital document is loaded for the first time into the electronic display device, the software for viewing this document, which may have been loaded beforehand in the memory of the electronic device or which can load at the same time as the document to be displayed, determines first place the screen size of the display device, according to a first identification code stored in the display device and representative of the screen size of

these measures.

  In addition, when the digital document is first loaded into the display device, this document or an annexed data file may also contain at least one second identification code representative of a

default font.

  The document viewing software then uses the identification code of this default font, combined with the identification code of the screen size of the viewing device, to determine one of the aforementioned codes C1-C6. This determination is made for example by means of a correspondence table similar to the table above, contained in the same data file.

  as the document to view or in an external file.

  Once this code has been determined, the viewing software searches for the different layout marks contained in the document to be viewed, which contain this identification code, and presents the document on the screen using these layout marks.

page.

  Subsequently, the user can also modify the font used, as already explained above, in which case the document viewing software again determines the identification code Cl-C6 corresponding to the combination of the size of screen and the group of fonts to which the font selected by the user belongs, then presents the document on the screen using the layout marks corresponding to the identification code C1-C6 thus determined.

Claims (24)

  1. Electronic document display device comprising an electronic central unit (5) which includes a memory (7, 9) and which is connected to a display screen (3) and to a control interface (4), the memory ( 7,9) of the central unit containing at least one   document in digital form which is intended to be presented on the screen and which comprises alphanumeric characters, this document consisting mainly of   by fixed information, characterized in that the document contains layout markers not visible on the screen which each include at least one identification code corresponding to a display configuration representative of the way in which the document is presented on the screen, the layout marks including at least page break marks which subdivide the document into pages and the identification codes understood by the various layout marks corresponding to several display configurations which themselves correspond to several layouts on the screen, in that the memory (7, 9) contains at least one identification code corresponding to an active display configuration, with which the document must be presented to the user. screen, and in that the electronic central unit (5) is adapted to lay out the document using the layout marks which correspond to the configuration of a active display and to present the document on the screen according to said active display configuration with a page break for each page jump mark corresponding to said active display configuration, the pages delimited by the page breaks which correspond to the active display configuration being such that each of these pages appears entirely on the screen when it   is displayed with the active display configuration.   2. Device according to claim 1, in which the memory (7, 9) contains characteristic data defining several possible types of characters, corresponding to several layouts on the screen, the command interface (4) being adapted for allow a user to choose a type of character from the different possible types, these types of characters being divided into several groups of types of characters each comprising: - either a single type of characters, - or several types of characters of similar sizes, the display configuration which corresponds to each layout marker comprising at least one group of character types, and the identification code of the active display configuration corresponding to at least one group of character types, known as a group active, to which the   type of characters chosen by the user.   3. Device according to claim 2, in which the page break marks each include a code which represents the corresponding page number: - either on a page situated immediately before the page break mark, when said page break mark corresponds to the active group, - either to a page located immediately after the page break mark, when said jump mark page corresponds to the active group.   4. Device according to claim 2 or claim 3, in which at least one of the groups of character types corresponding to the page break marks comprises several types of characters of similar sizes, the page break marks which correspond to this group. of character types being positioned in the document so that the different pages of the document delimited by these page break marks are fully visible on the screen for all the types of characters belonging to said group of character types when this group of types of characters is the active group. 5. Device according to claim 2 or claim 3, in which at least one of the groups of character types corresponding to the page break marks comprises several types of characters of similar sizes, the page break marks which correspond to this group. of character types being positioned in the document so that the different pages of the document delimited by these page break marks are fully visible on the screen for all the types of characters belonging to said group of character types when said group of types of characters is the active group, after an adaptation of size of each page by homothety, with a coefficient of homothety which is specific to each type of characters, and the central unit being provided to adapt the size of each page during the display of this page on the screen by applying to said   page a homothety with said coefficient of homothety.   6. Device according to claim 5, in which the central unit (5) is adapted to automatically determine a coefficient of uniformity specific to a page and to a type of characters, when displaying   this page with the type of characters considered.   7. Device according to any one of   claims 2 to 6, wherein when the user   chooses a new type of characters when an initial page was already displayed on the screen before resetting, the central unit (5) is adapted to display on the screen (3) a new page comprising at least one part of the initial page.   8. Device according to claim 7, in which the central unit (5) is adapted to receive from the user, via the control interface (4), information making it possible to determine said part of the page. initial which is included in the new page displayed on the screen after page layout of the document. 9. Device according to claim 7, wherein said part of the initial page which is included in the new page displayed on the screen after resetting the document, is a predetermined part of said initial page. 10. Device according to any one of   Claims 7 to 9, in which the central unit (5) is   adapted to present at least one visual signal highlighting said part of the initial page which is included in the new page displayed on the screen after resetting document page.   11. Device according to any one of   claims 2 to 10, wherein the central unit (5) is   suitable for storing in a permanent internal memory   (7) the last type of character chosen by the user.   12. Device according to any one of   claims 2 to 10, wherein the central unit (5) is   adapted to present on the screen (3) indications relating to an original layout, corresponding to a predetermined type of characters, whatever the type of   characters chosen by the user.   13. Device according to any one of   previous claims, in which the document   furthermore includes illustration marks corresponding to illustrations inserted in the text, these illustration marks being not visible on the screen and each comprising: - at least one identification code corresponding to a display configuration, - at least one code representative of the corresponding illustration, and coded position and / or size information, the electronic central unit (5) being adapted to present the document on the screen (3) with each illustration positioned and / or sized on the corresponding page as a function of said coded position and / or size information contained in the illustration mark of said illustration corresponding to the active configuration.   14. Device according to claim 13, in which the illustration marks further comprise coded information for the visual presentation of the illustrations, this coded information being representative of the optical characteristics of each   point belonging to the illustration.   15. Device according to any one of   previous claims constituting a book   electronic in the form of a box portable (2).   16. Device according to any one of   previous claims, in which the code   of each display configuration corresponds to at least one screen characteristic specific to the display screen (3).   The device according to claim 16, wherein said screen characteristic is a screen size. 18. Device according to any one of   claims 16 and 17, wherein the memory (7, 9)   contains characteristics defining several possible types of characters, corresponding to several layouts on the screen, the command interface (4) being adapted to allow a user to choose a type of characters from the different possible types, these types of characters being divided into several groups of types of characters each comprising: - either a single type of characters, - or several types of characters of neighboring sizes, each display configuration corresponding to a combination of at least one screen characteristic and at least one group of character types, and the identification code of the active display configuration corresponding to the combination: of the screen characteristic corresponding to the display screen of the device, - and of the group of character types to which   belongs to the type of characters chosen by the user.   19. Data carrier for an electronic document viewing device according to one   any of the preceding claims comprising a   interface (8) adapted to communicate with said data medium (9), this data medium having in memory at least one document in digital form which is intended to be presented on the screen (3) of the electronic device and which comprises alphanumeric characters, this document consisting mainly of frozen information, and said document containing layout marks not visible on the screen which each include at least one identification code corresponding to a display configuration, these marks layout corresponding to several display configurations which themselves correspond to several screen layouts, and said layout marks including at least page break marks.   20. Downloading method comprising at least one step consisting in downloading into the memory (7, 9) of an electronic document viewing device   according to any one of claims 1 to 18, at least   a document in digital form which is intended to be presented on the screen (3) and which comprises alphanumeric characters, this document consisting mainly of frozen information, and said document containing layout marks not visible to the screen which each include at least one identification code corresponding to a group of character types, these layout marks corresponding to several display configurations which themselves correspond to several screen layouts, are said layout guidelines including at least page break marks.   21. Method for viewing a document stored in digital form, by means of an electronic document viewing device according to one   any of claims 1 to 18 which comprises a unit   electronic central unit (5) including a memory (7, 9) and connected to a display screen (3) and to a control interface (4), the document being intended to be presented on the screen and comprising alphanumeric characters, and this document consisting mainly of frozen information, said document containing layout marks not visible on the screen which each include at least one identification code corresponding to a display configuration representative of the way in which the document is presented on the screen, the layout marks including at least page break marks which subdivide the document into pages, and the identification codes understood by the various layout marks corresponding to several configurations of display which itself corresponds to several layouts on the screen, the method comprising the following steps: a / determining the identification code of a conf active display, with which the document must be presented on the screen, b / lay out the document using the layout marks having an identification code which corresponds to the identification code of the configuration d active display and presenting the document on the screen (3) according to said active display configuration with a page break for each page jump marker corresponding to said active display configuration, the pages delimited by the page breaks corresponding to the active display configuration being such that each of these pages appears entirely on the screen when it   is displayed with the active display configuration.   22. The method of claim 21, wherein the different display configurations include different types of characters grouped into several groups of character types each comprising at least   a type of characters, step a / comprising the sub-   following steps: - choose a type of characters, - determine an identification code corresponding to the group of character types to which the chosen type of characters belongs, - and store this identification code in memory (7, 9) as that identification code of the active display configuration.   23. The method of claim 21, wherein the different display configurations correspond to several screen characteristics, step a / comprising the following substeps: - determining an identification code relating to the screen characteristic corresponding to the display screen (3) of the electronic document presentation device, - and memorize in the memory (7, 9) this identification code as identification code of the active display configuration.   24. The method of claim 21, wherein the different display configurations correspond to several screen characteristics and to several types of characters grouped into several groups of character types each comprising at least one type of character, step a / comprising the following sub-steps: - determining a first identification code relating to the screen characteristic which corresponds to the display screen (3) of the electronic document presentation device, - memorizing in the memory (7 , 9) the identification code corresponding to this screen characteristic, - choose a type of characters, - determine a second identification code corresponding to the group of character types to which the chosen type of characters belongs, - store in the memory (7, 9) this second identification code, - determining and storing in memory (7, 9) an identification code of the configuration of display   active, corresponding to said first and second identification codes.