GB2360740A

GB2360740A - Keypad with keys having contact points wherein a microprocessor identifies which key a user intended to select by the greatest number of points activated

Info

Publication number: GB2360740A
Application number: GB0107335A
Authority: GB
Inventors: Gilbert Stokoe
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-03-28
Filing date: 2001-03-22
Publication date: 2001-10-03
Also published as: AU3943101A; GB0107335D0; GB0007354D0; WO2001073804A1

Abstract

The keypad includes a series of keys wherein the surface of each key, for example the letter R key, comprises a series of contact points 1-5. If a user wishes to select the letter R key, the user contacts the key R. However, because of the small size of the keys, the user's fingers, shown by a broken line 6, will overlap adjacent keys T and F, and contact is made with two adjacent points thereon, viz., 7 on the T letter key and 8 on the F letter key. Because the finger was directed primarily at the R key, it contacts two points 3 and 5 thereon. A microprocessor monitors and identifies which points have been activated by the user and for which the key the greatest number of points been activated thereon and operates that key accordingly. Thus in this example, the microprocessor recognises that the user had intended to select the letter R key for operation. The keypad may be used in a typewriter, computer or a mobile telephone.

Description

2360740 1 IMPROVED KEYPAD The present invention relates to keypads, that

is to arrays of keys each of which is designed to produce a given effect when pressed or contacted either alone or in combination with one or more other keys. The invention is an improved form of such a keypad.

Keypads are of course much used for conventional purposes such as for controlling the operation of a typewriter, a computer or a telephone. When such latter devices are static and therefore often of significant size, it is relatively easy for the user of the device, especially a trained or experienced user, to operate the keys in the desired sequence either wholly accurately or with very little risk of error. However the rapidly increasing use of compact mobile telephones, computers and the internet has led to the adoption of increasingly compact keyboards, 2 with the result that it has become increasingly difficult for the user to operate a specific key without inadvertently contacting, and consequently operating, one or more adjacent keys. Quite apart from the operational errors which may arise as a result, the time required to correct any such errors is an undesirable consequence.

It is an object of the present invention to provide an improved keypad, by means of which the dimensions of the operating keys and therefore of the keypad itself may be reduced while reducing or eliminating the foregoing hitherto associated risk of operational error.

The present invention is a keypad comprising a plurality of keys, the contact surface of each of which comprises a plurality of areas, and means to monitor and identify which said areas have been activated by a person operating the keypad and for which said key the greatest number of areas have been activated. In this way, the monitoring means is able to determine which key was intended to be operated by the user of the keypad, even when one or more adjacent keys have been contacted, albeit unintentionally, by the user. As a result, the sizes and relative spacing 3 of the individual keys may be significantly less than in the case of a conventional keyboard or keypad, without the otherwise associated significantly increased risk of operating the wrong key in addition to the intended key.

One potential benefit of the reduction in key size which is made possible by means of the present invention is that, in a given area, for example that of a keypad for a mobile telephone handset, more keys may be included, thereby reducing or eliminating a need for repetitive operation of a single key.

As indicated above, the keys, and within each key the individual areas, which together form the keypad according to the present invention may be of the type which are required to be depressed, to at least a small extent, to operate them. However the invention is most advantageously applied to keyboards of which the keys are operated by contact. In order to avoid undue repetition, the subsequent description herein will therefore refer to keyboards of the contact type, although reference to keyboards of the other type is inferred where appropriate.

4 The contact surface of each key is divided into a plurality of areas. There may be as f ew as two such areas or as many as nine or more. The areas will normally be distributed symmetrically across the area of the key surface, usually with one such contact area being disposed at the centre of the key and the others symmetrically around that central area. In one particularly preferred form of the invention, the key surface has one contact area at its centre and four such areas around it, that is five contact areas in total. This latter distribution of contact areas is of particular value when the keys overall are square in plan. However it is to be emphasised that the invention is also of value when the keys are of a different shape from square, for example circular or segmental in plan, or when the keys forming the keypad are of different shapes from each other.

Although a primary feature of the present invention is to identify just which key or combination of keys in a display of keys forming a keypad the operator had intended to operate, the response of the keys may be prioritised in the sense that, when a given predetermined combination of two or more keys are contacted simultaneously, a specific one key or combination of those keys will respond before the other key or keys. For example, if the keypad is that of a mobile telephone, the "',send" key to transmit a signal may be operable only after a given total or sequence of figures has been entered.

As described above, the keypad operates by identifying for which of the keys of the keypad the greatest number of areas have been activated. This assessment may readily be made by a microprocessor located within the device which carries the keypad, that is within the mobile telephone, internet access handset or handheld computer, to which microprocessor the key areas are linked mechanically or electrically.

While, in the foregoing description, I have described the device on the basis that the signals generated by each of the areas of a given key are identical, if desired, those areas may be prioritised by arranging for the central area of each key to produce a greater signal than the other areas of that same key. However, in general, the effectiveness of the keypad according to the present invention is such that such prioritising is not normally necessary.

The microprocessor which, by assessing the received signal, identifies the key selected by the operator of 6 the keypad, may of course perform other functions generally associated with the relevant activity. For example, it may indicate that an inappropriate key or keys has been activated, or that an error of activation or of transmission has occurred.

The invention will now be further described, by way of example only, with reference to the accompanying drawings, which illustrate schematically one preferred possible form of keypad according to the present invention and wherein:- Fig 1 is a plan view of a part of the area of a conventional QWERTY keyboard; Fig 2 is a detailed view, to a larger scale, of a part of the area of such a keyboard incorporated in a keypad according to the present invention.

Fig 3 is a perspective view of a mobile telephone unit incorporating a keypad according to the present invention; and Fig 4 is a perspective view of one possible form of keypad cover which may be fitted over the keys of the unit shown in 7 Fig 3 in order to simplify the operation of that unit.

Fig 1 shows, by way of example, an area comprising twentyeight keys of what may, for instance, be those of a typewriter keyboard. In practice, of course, the individual rows of keys are conventionally staggered somewhat and the keys in each row are likely to be slightly spaced apart along the row. However, if that keyboard were required to be incorporated in as compact a form as possible in a small unit such as a mobile handset, then it is desirable that all of the keys be placed, each as small as possible, as close together as the operating convenience of the unit allows. Thus, by way of example, the individual keys in the keypad according to the invention as illustrated in Fig 2 may measure as little as 5 to 20 millimetres square, or even less.

As illustrated, each of the nine keys shown in Fig 2 has incorporated in its surface a total of five highly sensitive contact points, set symmetrically in a cross layout. Thus the W key has contact points 1 to 5, set in this illustrated example in this cross form. As one alternative, these contact zones could be disposed on the diagonals of the key surface.

8 Because these keys are so much smaller than many conventional keys, it is almost inevitable that the user's finger, as applied to any given key, will overlap other keys. The area 6 shown in broken line in Fig 2 represents that of a user's finger, intended to be applied to the letter R key. As shown, the finger also contacts two adjacent contact points, namely the point numbered 7 on the IT' pad and that numbered 8 on the 'F' pad. However, because the user's finger was directed primarily at the 'R' key, it contacts two such points, namely those numbered 3 and 5 respectively, on that key.

Thus the microprocessor associated with the keypad of Fig 2 receives signals from the W, IT' and IF' keys. However, since the signal from the first of these three keys is received from the two points 3 and 5, while that from each of the 'IT' and IF' keys is from a single point in each case, the microprocessor can be programmed to recognise that the user had selected the "R' key for operation and may be designed to ignore the lesser signals from the IT' and IF' keys.

In the second illustrated example in Fig 2, the finger contact 9 activates the points 10 and 11 in the 'Y,' 9 key and only the single point 12 on the 'H' key and is therefore recognised as indicating the user's intention to operate only the first of those two keys. Thus only the xyf key is operated by the microprocessor.

In the foregoing examples, only two or three adjacent keys have been illustrated as having been pressed simultaneously. However, as progressively smaller keyboards are developed for various purposes, the possibility or even likelihood that a single finger pressure may potentially operate even more keys, for example all nine of those illustrated in Fig 2, makes the potential benefits attributable to the present invention of even greater significance in that in general it is the key having most activated areas which is identified as that intended to be activated by the operator.

Thus Fig 3 illustrates a mobile telephone handset 19 having an alphanumeric keyboard to control its operation. As may readily be seen, a finger operating, say, the '14' key will almost inevitably make contact with at least the adjacent '3f 1 X51 'ARf T' and 'Y' keys. However, because the telephone handset 19 incorporates a keypad according to the present invention, and because therefore it is likely that more sub-areas of the '4' key will have been contacted than sub-areas of the other adjacent keys, the unit will recognise that the operatorfs intention was to operate the '4' key.

As will therefore be apparent, whichever key is intended to be operated by the user of the illustrated handset 19 will be duly operated as intended. However, the user of the handset, especially an impatient user or one with restricted vision, may find the keys not required for, say, a simple local telephone call to be a potential distraction to the user. With that in mind, the keypad cover 20 illustrated in Fig 4 of the accompanying drawings has been devised. 'That cover 20 is of such dimensions as to be readily slid into place over the keyboard keys of the Fig 3 telephone handset, in order to provide a simpler supplementary keyboard. As one alternative, the cover 20 could be replaced by a supplementary keyboard hinged at one end to the Fig 3 handset to enable it to pivot into a position overlying the keys of the latter handset.

With the main keys of the handset 19 overlain in this way, only the essentially numerical keys of the keypad cover 20 will. be accessible to the handset user. Fitting of the cover 20 into place is accompanied by an essential. aiLt-omati-c re-assig-ning- of- the handset keys to take account of the new positions of the number markings on- the- keys. Thus pressi-ng the '4' key on the cover 20 will depress, say, the keys marked '121 and ',3', and possibLy th-e "E-' and "R' keys., on the handset itself and the handset will recognise this as an intention to send a 141 signal and will act accordingly.

The illustrated handset 19 and the cover 2.0 may each or either have individual keys which may move as they are operated but it Ls particularly preferred that the keyboards be units in which the individual keys are integrated. together but may separately be pressed to operate them. However, as a less preferred alterna-ti.ve, the keys, may each be s.epa-ra-te from the other keys; if desired, such separate keys could be covered.by a flexible membrane-.

12

Claims

1 A keypad comprising a plurality of keys, the contact surface of each of which comprises a plurality of areas, and means to monitor and identify which said areas have been activated by a person operating the keypad and for which said key the greatest number of areas have been activated.

2. A keypad as claimed in Claim 1, wherein said keypad areas are activated by depressing them.

3. A keypad as claimed in Claim 1, wherein said keypad areas are activated by contact.

4. A keypad as claimed in any of the preceding claims, wherein the contact surface of each said keypad comprises one centrally-disposed said keypad area and a plurality of other said keypad areas disposed symmetrically around said central area.

5. A keypad as claimed in Claim 4, comprising four other said keypad areas.

6. A keypad as claimed in any of the preceding claims, wherein said keys are square, circular or segmental in plan.

7. A keypad as claimed in any of the preceding claims, wherein the response of the keys in the keypad is prioritised.

13

8. A keypad as claimed in any of the preceding claims, wherein the response of said keypad areas is prioritised.

9. A keypad as claimed in any of the preceding claims, wherein the means to identify and assess the keypad areas which have been activated comprises a microprocessor to which the keypad areas are linked mechanically or electronically.

10. A keypad as claimed in Claim 9, wherein said microprocessor is able to indicate that an inappropriate key or keys has been activated or that an error of activation or of transmission has occurred.

11. A keypad substantially as hereinbefore described with reference to, and as illustrated in, Fig. 3 or Figs 3 and 4 of the accompanying drawings.