GB2121586A - Improvements relating to display devices - Google Patents

Abstract

A portable display device comprises a circuit board (10) having a plurality of electrically energizable light emitting means (14), e.g. liquid crystal cells, in a pictorial data field (15), a plurality of electric switches (16) identified, e.g. numbered (17) and a logic element (18) electrically connected in circuit between the switches and the light emitting means. In use, operation of a predetermined number of selected switches provides an electrical code signal which is decoded by logic element (18) to energize a light emitting means at a position within said pictorial data field that corresponds to the coded data represented by the particular said selection of switches. The pictorial field may be a map and the readable data (23) a list of places on the map, with associated code (24) indicating the switches to be operated. Two boards can be hinged together, one carrying styles - operated switches, each operating the appropriate light source on the pictorial field on the other board. <IMAGE>

Description

SPECIFICATION Improvements relating to display devices This invention relates to display devices.

A gazetteer and its associated map are customarily related to one another by means of an arbitary grid drawn over the map and having its rows and columns identified by symbols, for example letters across and numerals downwards. In order to locate a named place, street, theatre etc., the user first locates the entry in the gazetteer and reads its grid reference, and then turns to the map firstly to find the correct grid square and then to find the place within that square. This can be time consuming. If the grid squares are too small it takes time visually to locate and fix the correct square, and on the other hand if the grid squares are too large it takes time to locate the place within the identified square. These visual processes are particularly difficult for a traveller actually on the move, e.g. in a crowded city centre or transport vehicle.

An object of the invention is to provide a more effective portable display device, particularly for rapid and reliable indication of a desired location.

According to the present invention there is provided a portable display device comprising a circuit board having a plurality of electrically energisable light emitting means and a pictorial data field visually associated with said light emitting means, terminals for connecting a battery to said circuit board, a plurality of electric switches and readable data visually associated with each said switch, and a logic element electrically connected in circuit between said switches and the light emitting means so that in use operation of a predetermined number of selected said switches provides an electrical code signal which is decoded by said logic element to effect energisation by said battery of a light emitting means at a position within said pictorial data field that corresponds to the coded data represented by the particular said selection of switches.

An embodiment of the invention will now be described, by way of Example, with reference to the accompanying drawing, which is a schematic view of an open pocket sized electronic map according to the invention.

The drawing shows a pocket-sized electronic map comprising a printed circuit board 10 and one or more, e.g. four, plasticized paper pages 11 assembled together in the manner of a book for opening and closing about a flexible spine line 12. The circuit board and the pages are preferably received within cladding material 13 to give a durable exterior when the map is closed. When closed the device should measure no more than about 22 x 12 x 2 centimetres and preferably no more than about 17 x 10 x 1 centimetres so that it can readily be carried in the side pocket of a standard gentlemen's jacket.

The circuit board 10 is provided with a plurality of electrically energisable light emitting means 14. In a preferred embodiment the circuit board carries a liquid crystal cell and the light emitting means 14 are defined by positions on the cell adjacent a corresponding plurality of electrodes on the circuit board.

The light emitting means of each position is selectively energisable by a voltage applied to the appropriate electrode, typically through a matrix of row and column lines.

The circuit board 10 also carries a pictorial data field 15 visually associated with the light emitting means 14. In the preferred embodiment, the data field is printed on a transparent plastics material film in area contact with the upper surface of the liquid crystal cell, and the film and cell are protected by a front sheet of thin glass or rigid transparent plastics material. By way of example the illustrated field shows a portion of a map of an urban railway system with a light emitting means, e.g. a liquid crystal cell area, in the position of each station and possibly in additional positions.

The circuit board also carries a column of switches 16 and readable data 17 associated with each switch.

There are preferably ten switches identified by printed numerals 0 to 9 beside the respective switches. The switches may be adapted for operation by means of a stylus, e.g. the point of a ball point pen. The switches are preferably miniature spring-loaded push-button switches with concave heads, for example as employed in miniature electronic calculators.

The circuit board also carries a logic element 18 electrically connected by the circuit board lines in circuit between the switches and the light emitting means, e.g. the energising electrodes of the liquid crystal cell areas. The logic element is adapted, i.e.

pre-programmed, to respond to sequences of signals from the switches, for example to respond to receipt of a sequence of three signals caused by three operations of any of the switches. The three switch signal sequence forms an electrical code signal which is decoded by the logic element. The actual three operations of switches 16 are temporarily stored in an input register and then entered into and decoded by the logic element 18 upon depression of an "enter" switch 19.

The device includes a receptacle 20 for reception of two disc-shaped batteries no more than about 5 millimetres in thickness, and terminals 21 for connection to the battery. An on/off switch 22 is connected between the terminals and the circuit board.

The plasticized paper pages 11 carry arrays of printed data in pairs of columns 23, 24. Each column 23 has written data items and each column 24 has a three digit code number adjacent the respective written data items. The written data may be grouped in sections of items of different types, e.g. railway stations, streets, theatres, stores and museums. The use of a three digit code permits up to 999 written data items on the pages 11. It will be appreciated that the code may be of one or more digits. A four digit code would permit up to 9999 written data items.

To operate the device, the user scans the written data on pages 11 and finds the name of a place he wishes to locate on the map, e.g. "Oxford Circus" when the pictorial data field 15 is a map of the London Underground System. Beside the name is a three digit code, e.g. 255. The user presses once the switch beside number "2", then presses twice the switch beside numeral "5", and then presses the "enter" switch 19. The logic element 18 decodes the signal "255" and energizes the light emitting means 14 at the position of a station "Oxford Circus" on the map. Clearly two or more codes may be decoded by the logic element to energize a single lamp, e.g.

"Chancery Lane" in the column "stations" and "Patent Office" in the column "Public Buildings".

This will depend on the nature and details of the written data array 23,24 and the pictorial data field 15 in any particular embodiment.

Other examples of display devices according to the invention include devices in which the pictorial data field is a town map and the data array lists roads, streets, avenues, places, etc.; the pictorial data field may be a marine chart and the data array gives depth soundings, buoys and pilot channels; the pictorial data field may be a world map and the data array gives distances between points in miles or kilometres. orthe pictorial data field may be a map of a group of islands such as the Bahamas, the data array being a gazetteer thereof.

The light emitting means may be energized to give steady illumination, but is preferably energized to flash repetitively so as more readily to catch the user's eye. The light emitting means at a position may comprise point illumination, line illumination, on geometrical shape illumination such as a square or circle, in each case preferably flashing repetitively. An electronically generated steady or intermittent tone may accompany energisation of a light emitting means.

A second embodiment of the invention will now be described, by way of Example, with reference to Figure 2 of the accompanying drawing, which is a schematic view of an opened pocket-sized electronic map according to the invention.

The drawing shows a pocket-sized electronic map comprising first and second printed circuit boards 110,111 hinged together in the manner of a book, by means of a hinge pin 112. A flexible material hinge would be an alternative. The circuit boards are preferably received within cladding material to give a durable exterior when the map is closed. When closed the device should measure no more than about 20 x 12 x 2 centimetres and preferably no more than about 17 x 10 x 1 centimetres so that it can readily be carried in the side pocket of a standard gentlemen's jacket.

The first circuit board 110 comprises a plurality of electric switches 113 operable by means of a stylus, e.g. the point of a ball point pen. The switches are preferably miniature spring-loaded push-button switches with concave push-button heads no more than about three millimetres in diameter, for example as employed in wrist-watch calculators. The first circuit board also carries an array 114 of written data, each item 115 of the data being visually associted with one said switch 113. The written data may be grouped in sections or columns of items of different types, e.g. railway stations, theatres, stores, museums. There is space for several hundred legible items 115 and styius-operable switches 113 in an array 114 of dimensions of the order indicated above.

The second circuit board 111 comprises a plurality of electrically energisable light sources 116. The light sources are preferably miniature electric lamps having a diameter no more than about 3 millimetres.

The second circuit board also carries a pictorial data field 117 visually associated with the light sources.

By way of example the illustrated field shows a portion of a map of an urban railway system with a light source 116 in the position of each station and possibly in additional positions.

The device includes a receptacle 118 for reception of a disc-shaped battery no more than about five millimetres in thickness and terminals 119 for connection to the battery. The electrical circuit paths on the two printed circuit boards are connected to one another by flexible electrical connections, some of which are indicated at 120, around the hinge pin 112.

The electrical connections between the batteryter- minals 119, the swiches 113 and the light sources 116 are arranged so that in use operation of each switch 113 effects energisation of a light source 116 at a position in field 117 that corresponds to the written item 115 associated with that switch 113.

For example, operation of the switch 113 beside the written name of "Oxford Circus" would energise the lamp 116 at the position of the station "Oxford Circus" where the pictorial field 117 is a map of the London Underground System. Operation of the switch beside the written name of "Patent Office" would energise the "Chancery Lane" Station lamp, or possibly a separate lamp adjacent the lamp representing the station "Chancery Lane". Clearly, two or more switches 113 may be connected to a single lamp 116, and a single switch 113 may energise two or more lamps 116, depending on the nature and details of the written data array 114 and the pictorial data field 117 in any particular embodiment.

Claims (22)

1. A portable display device comprising a circuit board having a plurality of electrically energizable light emitting means and a pictorial data field visually associated with said light emitting means, terminals for connecting a battery to said circuit board, a plurality of electric switches and readable data visually associated with each said switch, and a logic element electrically connected in circuit between said switches and the light emitting means so that in use operation of a predetermined number of selected said switches provides an electrical code signal which is decoded by said logic element to effect energization by said battery of a light emitting means at a position within said pictorial data field that corresponds to the coded data represented by the particular said selection of switches.

2. A display device as claimed in claim 1 wherein the plurality of light emitting means are provided by a liquid crystal cell.

3. A display device as claimed in claim 2 wherein the pictorial data field comprises a printed sheet of transparent plastics material in area contact with the viewing side of the liquid crystal cell.

4. A display device as claimed in any one of claims 1 to 3 wherein each said switch comprises a miniature spring loaded push button switch adapted for operation by means of a stylus.

5. A display device as claimed in any one of claims 1 to 4 including a receptacle for receiving a disc-shaped battery no more than about 5 millimetres in thickness for connection to said terminals.

6. A display device as claimed in any one of claims 1 to 5 wherein operation of at least of one individual said switch effects energization of at least two said light emitting means.

7. A display device as claimed in any one of claims 1 to 6 wherein the device includes at least one page of printed data assembled together with the circuit board in the manner of a book.

8. A device as claimed in claim 7 wherein the device when closes measures no more than about 22 centimetres x 12 centimetres x 2 centimetres.

9. A display device as claimed in any one of claims 1 to 8 wherein said pictorial data field includes a map of a railway system, a said light emitting means being disposed at the position of each station on the map.

10. A display device as claimed in any one of claims 1 to 9 wherein said pictorial data field includes a map of a town, a said light emitting means being disposed at the position of each prominent building on said map.

11. A display device as claimed in any one of claims 1 to 10 wherein said pictorial data field includes a map of a town, a said light emitting means being linear and disposed along at least a portion of each of selected streets on said map.

12. A display device as claimed in any one of claims 1 to 11 wherein each said light emitting means is adapted to flash repetitively upon energisation thereof.

13. A portable display device comprising first and second circuit boards hinged together in the manner of a book, and terminals for connecting a battery to said device, the first circuit board comprising a plurality of electric switches operable by means of a stylus and said first board having written data visually associated with each said switch, the second circuit board comprising a plurality of electrically energisable light sources and said second board having a pictorial data field visually associated with said light sources, and electric connections between said battery terminals, said switches and said sources arranged so that in use operation of each said switch effects energisation of a said light source at a position within said pictorial data field that corresponds to the written data associated with that switch.

14. A display device as claimed in claim 13 wherein said circuit boards are printed circuit boards and said electric connections include flexible electric connections across the hinging between said boards.

15. A display device as claimed in claim 13 or claim 14 wherein each said electric switch comprises a miniature spring-loaded push-button switch, the push-button having a diameter of no more than about3 millimetres.

16. A display device as claimed in any one of claims 13 to 15 wherein each said light source is a miniature electric lamp having a diameter no more than about 3 millimetres.

17. A display device as claimed in any one of claims 13 to 16 including a receptacle associated with one of said boards for receiving a disc-shaped battery no more than about 5 millimetres in thickness for connection to said terminals.

18. A display device as claimed in any one of claims 13 to 17 wherein operation of at least one individual said switch effects energisation of at least two said light sources.

19. A display device as claimed in any one of claims 13 to 18 wherein said device measures, when the circuit boards are folded together in the manner of a closed book, no more than about 20 centimetres by 12 centimetres by 2 centimetres.

20. A display device as claimed in any one of claims 13 to 19 wherein said written data includes the names of railway stations and said pictorial data field includes a map of the railway system which includes said stations, a said light source being disposed at the position of each station on the map.

21. A display device as claimed in any one of claims 13 to 20 wherein said written data includes the names of prominent buildings in a town and said pictorial data includes a map of that town, a said light source being disposed at the position of each said building on said map.

22. A pocket-sized electronic map substantially as described herein with reference to Figure 1 or Figure 2 of the accompanying drawings.