Using touchscreen by pointing means

[0001] The invention relates to using small, portable devices comprising a touchscreen by a pointing means, and particularly to using such a device single-handedly.

[0002] The screens in computers used in public places, such as in ticket vending machines, are usually touchscreens. Selections are typically made using a finger as a pointing means. Such screens are large, so the buttons and other elements to be activated can also readily be large enough. Furthermore, applications often enable selections to be easily made between only a few alternatives, and usually no text, for example, needs to be entered either.

[0003] Touchscreens are often utilized in portable PDA (Personal Digital Assistant) devices that are becoming increasingly popular. Since most functions can also be implemented through keys modelled on a screen, a touchscreen substantially reduces the number of necessary mechanical keys. Consequently, such devices become smaller. Since the aim is to make the portable PDA devices as small as possible, the touchscreens used therein are also small. Furthermore, the functions of the applications in the devices are more versatile, and a screen can be provided with many elements to be selected. For example, the buttons of a qwerty keyboard can be modelled on a touchscreen in order to enable text to be entered. Since the screen is small and several elements to be selected are simultaneously displayed on the screen, the elements are substantially small. In addition to the modelled keys, another frequently used input mechanism is handwriting recognition. Thus, on account of the small keys and handwriting recognition, a touchscreen is often used by means of a small writing device, i.e. a stylus, such as a small pen-shaped object.

[0004] On many occasions it would be desirable to use a PDA device with one hand only. This is a problem when a touchscreen requires a stylus to be used as the pointing means. Using a stylus typically necessitates two hands; one for holding the device and the other for using the stylus to point at a desired point. It can be inconvenient and too time-consuming to extract a stylus from its storage slot in order to execute minor functions. Sometimes the small stylus may also be lost. In these situations, the user often eventually uses his or her finger as the pointing means. When the elements to be indicated are very small, e.g. on the touchscreens of the PDA devices, the surface area of a fingertip is, however, rather large with respect to these elements. A finger is an extremely inaccurate pointing means since it completely covers a target to be selected and important information around the target as well. In such a case, the user cannot be sure as to which elements he or she is pointing at.

[0005] In connection with large touchscreens, a solution is known wherein a user is able to determine the location of a pointer where the location of the pointer and the contact on the screen differ from each other (Offset). This solution enables the pointer to be removed from directly under the finger such that the user can more easily see what the pointer is currently pointing at. In the solution, the user is not shown in advance how the pointing means actually works. The user, according to a common practice, assumes that the cursor moves to the contact point since the user is not informed about the offset already setup in the device. The pointer moves to a different point than assumed and desired by the user, and this makes the device slower to use, or may result in pointing and selecting incorrect targets. Even after the user has realized how the pointing works, he or she must bear the extent of the offset in mind in order to be able to operate the device smoothly.

[0006] An object of the invention is thus to provide a method and an apparatus implementing the method so as to enable the accuracy of pointing with a finger, for example, to be improved.

[0007] The idea underlying the invention is that a cursor (a virtual stylus), which comprises a handle part and a pointing part, is displayed on a touchscreen. When a user points to a screen by a pointing means, which can be a finger, for example, the handle part of the virtual stylus moves to the indicated point. The pointing part moves along with the handle part but is located at a substantially different point than the handle part such that the point indicated by the pointing part can be seen from under the pointing means. The pointing part shows on which point, on which element, for example, the activation of the virtual stylus is focused. After the user has made his or her selection, the element indicated by the pointing part is activated and the device executes the function associated with the element.

[0008] An element displayed on a screen may be a button, a key, or a text field, for example.

[0009] A function associated with an element is the operation executed by a device. Possible functions include starting an application, creating a new file, entering a selected letter into a text field and displaying such a letter on the screen or connecting a call to a desired number, for example. In practice almost all features and operations of a device can be functions.

[0010] An advantage of the method and device of the invention is that it also enables small elements to be selected on a touchscreen when a finger, for example, is used as a pointing means. This enables small devices to be used with one hand. An advantage of the virtual stylus of the invention is that the user, already before pointing, sees what the distance between the contact point and the indicated point will be. It is easier for the user to anticipate and select targets by placing the pointing means directly at a correct point with respect to the target to be selected without having to perform any readjustments in order to bring the pointing part onto the target. This makes the device faster to use and reduces the number of erroneously selected targets.

[0011] The invention is now described in closer detail in connection with the preferred embodiments and with reference to the accompanying drawings, in which

[0012] FIG. 1 is a block diagram showing an electronic device according to a preferred embodiment of the invention,

[0013] FIG. 2 shows a user interface according to a preferred embodiment of the invention,

[0014] FIG. 3 is a flow diagram showing the operation of a virtual stylus according to a preferred embodiment of the invention, and

[0015] FIG. 4 is a flow diagram showing how the virtual stylus is used according to a preferred embodiment of the invention.

[0016] FIG. 1 is a block diagram showing an electronic device (ED), which can be a wireless mobile station or a PDA (Personal Digital Assistant) device, for example, according to a preferred embodiment of the invention.

[0017] The electronic device (ED) comprises a central processing unit (CPU), memory (MEM) and an input/output (I/O) system. All necessary information is stored in the memory (MEM) of the device. The memory (MEM) comprises a read-only memory part, which can be ROM memory, for example, and a read/write memory part, which may consist of RAM (Random Access Memory) and/or FLASH memory, for example. Through the I/O system (I/O), the device communicates with other devices, a network and a user, for example. A user interface (Ul), which is part of the I/O system (I/O), comprises a necessary interface, such as a screen, keys, a loudspeaker and/or a microphone, for example, for communicating with the user. The screen of the device is a touchscreen. The information received from different components of the device is delivered to the central processing unit (CPU), which processes the received information in a desired manner.

[0018] The invention can be applied in connection with substantially all touchscreen types, but the touchscreen type used per se is irrelevant to the implementation of the invention. The implementation of a touchscreen may be based on one of the following techniques, for example: electrical methods, technology based on infrared light, technology based on sound waves or pressure recognition. Some touchscreen types require a stylus with integrated electronics, such as a resonance circuit. The operation of such a screen requires a stylus to be used, and the screen cannot be used by pointing with a finger, for example. Such a screen type also allows a virtual stylus to be used.

[0019] FIG. 2 shows a user interface according to a preferred embodiment of the invention. The screen 200 is a touchscreen having some qwerty keyboard buttons 202 modelled therein and some function keys 204 provided at the bottom of the screen. By activating a letter key 202, i.e. by selecting it by a pointing means, the user is able to enter letters into the device and thus produce text. A virtual stylus 206 operating as a cursor comprises two parts. The grey area represents a handle part 208 of the virtual stylus 206, which designates the area onto which the pointing means, such as a finger, is placed. The user should also be able to see elements and other possible information underneath the handle part 208. According to a first preferred embodiment, the handle is partly transparent, as shown in the figure. According to a second preferred embodiment, the handle resembles a ring, in which case the area in the middle is shown in an ordinary manner. According to a third preferred embodiment, the handle part can be an inverse of the screen below, in which case the user is still allowed to see the information on the screen, only the colour changes.

[0020] An arrow-shaped pointing part 210 shows the exact location of the targeted point. When the user points to the screen 200 by the pointing means, such as a finger, the handle part 208 of the virtual stylus 206 moves to the contact point, i.e. underneath a finger, for example. Since the pointing part 210 is connected to the handle part 208, the pointing part 210 also moves along with the handle part 208. The shape, size, positioning and direction of the pointing part 210 with respect to the handle part 208 can be changed if necessary. When designing and positioning a pointing part 210, it is, among other things, advisable to take the screen properties, requirements set by application and purpose of use of a device into account. The user can also be provided with an opportunity to modify the properties of the pointing part 210. It may also be reasonable that the pointing part 210 changes also during use if thus required; for example, if the elements to be selected reside over the entire area of a touchscreen. In order to select the function keys 204 in the figure the pointing part 210 could, for example, be turned to point downwards as seen from the handle part 208. Alternatively, if the direction of the pointing part is not to be changed, the edges of the screen can be provided with status information, for example, which does not need to be pointed, or the touchscreen can be larger than the area in which the elements to be selected can reside.

[0021] The size of the handle part 208 may also have to be changed according to the size of a finger, for example. However, the handle part 208 should be large enough and the pointing part 210 should be placed so as to prevent the pointing part 210 from becoming entirely concealed by a pointing fingertip. In order to use the device single-handedly, the most natural pointing means would be the thumb. Of all fingers, the surface area of a thumb is the largest one, and this is also to be taken into account while modifying the size of the handle part 208. In addition, the handle part 208 and the pointing part 210 do not necessarily have to be adjoined with each other but they can also be located separately.

[0022] According to a preferred embodiment of the invention, the user is able to modify the above features of both the handle part 208 and the pointing part 210.

[0023] FIG. 3 is a flow diagram showing the operation a virtual stylus according to a preferred embodiment of the invention. The touchscreen of a device identifies the intensity of a touch. A threshold value for touch intensity is stored in a memory. A touch stronger than the threshold value is interpreted as a strong touch and a touch lighter than the threshold value as a light touch. The touchscreen is provided with at least one element, such as a button, which can be selected by a user. The selection of a button results in a function associated with the particular button. In addition to the element, the screen displays a cursor, i.e. a virtual stylus, which comprises two parts: a handle part and a pointing part 300. The user uses a finger, for example, as a pointing means, placing it lightly (light touch) onto the screen 302. The screen detects the location and intensity of the touch, and the device moves the handle part of the virtual stylus to the point touched by the finger, i.e. underneath the finger 304. If the user moves his or her finger on the screen 306, the device detects this and updates the location of the stylus 304. If the finger is taken off the screen, the stylus remains in its place, at the point the user touched last, both the handle and the pointing part being visible. After the user has focused the pointing part of the virtual stylus on a desired target, on a button, for example, he or she may select an element 308 by pressing the screen harder (strong touch). After the user has selected the element 308, the device checks the target 310 and activates the element. Next, the device executes the function 312 associated with the element and if necessary, gives the user feedback on the selection and the possible function executed.

[0024] The technology in the most common screens does not, however, enable a screen to distinguish different touch intensities. The cursor can then be moved on the screen as described above but the actual selection, i.e. selecting an element 308, would, according to a preferred embodiment, take place when the user removes his or her finger from the screen. The technology in more advanced screens, in turn, enables the location of a fingertip to be identified already before the actual touch. In such a case, the virtual stylus could be moved by moving a finger close to the surface of the screen without touching it, however. An element would be selected 308 by actually touching the screen.

[0025] FIG. 4 is a flow diagram showing the operation of a virtual stylus according to a preferred embodiment of the invention. In some situations, the screen is incapable of displaying all desired information at once, for example while reading WWW pages or while processing an extensive text file. In such a case, it should be possible to scroll, two-dimensionally, the contents of a document being displayed on the screen. However, pointing and selecting elements should still be possible. When the user then points to the screen 400, the screen informs the central processing unit (CPU) about the pointing and its location. The central processing unit compares the received pointing location information with the previous location of the virtual stylus 402. If the distance from the stylus is longer than the predetermined threshold value stored in the memory (MEM), the device interprets that the user wishes to scroll the screen and select no element (scrolling mode) 404. If, again, the pointing takes place close to the virtual stylus, i.e. the distance is shorter than the threshold value, the device interprets that the user wishes to use the virtual stylus for selecting elements (pointing mode) 406. The virtual stylus is then moved underneath the finger, and the device operates as shown in FIG. 3.

[0026] When the device is in the scrolling mode 404, the user should also be able to slide his or her finger over the virtual stylus without the device interpreting that the user wishes to use the virtual stylus. If the user removes his or her finger from the screen during scrolling, a new contact point will be processed as described above and the mode in use will be selected according to this point. According to a preferred embodiment of the invention, when the device starts the scrolling mode the virtual stylus disappears from the screen and will not return until the finger is removed from the touchscreen. This gives the user clear feedback on the mode being currently used.

[0027] According to a preferred embodiment, the threshold value can be determined in such a manner that the pointing mode, herein the virtual stylus, is preferably activated when the user grabs the handle, i.e. when the point touched by the user at least partly resides within the area of the handle. This is intuitive, clearly giving the user feedback on the operation of the device. When the user touches an area outside the handle, the device starts another mode, such as the scrolling mode.

[0028] It is preferable to use the virtual stylus of the invention when several different modes are used. It will be evident to one skilled in the art that an alternative mode to the pointing mode does not necessarily have to be the scrolling mode according to the example described above but the invention can be applied in connection with other corresponding modes as well.

[0029] According to a preferred embodiment, when the user grabs the handle, more than one virtual stylus can be displayed on the screen simultaneously. This enables several different functions to be implemented in a preferred manner. The different operation of the styluses can preferably be indicated e.g. by shaping the pointing part differently. For instance, a screen can be provided with a stylus whose pointing part resembles a pen for drawing a line and another stylus whose pointing part resembles an eraser for erasing.

[0030] A screen may also support the use of several different pointing means, such as a pen-like stylus or a finger. In such a case, the device should recognize the method the user employs in a given situation. A way to distinguish a pointing means is to identify it by the contact area. The contact area of a finger is clearly larger than that of a pen, which means that the identification can be based on the size of a contact area. Alternatively, a device can identify whether or not a stylus resides in its storage slot. When the stylus resides in the slot, the device knows that a finger is used for selecting elements. On the other hand, when the stylus is removed from the slot, the device knows that the stylus is used. In addition to the methods mentioned above, the user may be provided with an opportunity to manually select which pointing means he or she wishes the device to assume to be used. This can be implemented e.g. using a setting menu or a mechanical key. Different methods may also be used together. When the pointing means is a finger, the virtual stylus of the invention can preferably be used. When the device assumes that a finger is used as the pointing means, a virtual stylus is shown on the screen. When, again, it is assumed that a stylus is used, no virtual stylus is shown. This gives the user clear feedback as to which pointing means the device assumes to be used. When contact area identification is used, the pointing means used last can be taken as a default.

[0031] It should be evident to one skilled in the art that as technology progresses, the basic idea of the invention can be implemented in many different ways. The invention and its embodiments are thus not restricted to the examples described above but they may vary within the scope of the claims.