WO2006112768A1

WO2006112768A1 - Pointer control device

Info

Publication number: WO2006112768A1
Application number: PCT/SE2006/000411
Authority: WO
Inventors: Tomas ÖQUIST; Gunnar Drougge; Magnus Schnürer; Kurt Högnelid
Original assignee: ERGOPTION AB
Current assignee: ERGOPTION AB
Priority date: 2005-04-21
Filing date: 2006-04-05
Publication date: 2006-10-26
Anticipated expiration: 2007-10-21
Also published as: SE529322C2; SE0500907L

Abstract

The present invention relates to the production of control commands (CmdP) that influence the position of a graphical pointer on a computer system display. A proposed pointer control device (100) comprises an essentially flat sensor surface (110) delimited by means of a boundary wall (115). An actuator object (130) having an essentially flat actuator surface is slided over a sensor means (120) in the sensor surface (110) to generate the control commands (CmdP). The actuator object (130) has such a configuration and such geometric proportions relative to a set of geometric proportions of the boundary wall (115) that when the actuator object (130) is placed on the sensor surface (110) with the actuator surface facing the sensor surface (110) and the actuator surface is positioned entirely within the boundary wall (115) the actuator object (130) is slidable over the sensor surface (110). Moreover, a portion of the actuator object (130) always covers the sensor means (120).

Description

Pointer Control Device

THE BACKGROUND OF THE INVENTION AND PRIOR ART

The present invention relates generally to the production of position related commands for controlling graphical events on a computer system display. More particularly the invention relates to a pointer control device according to the preamble of claim 1.

As many people today spend a significant amount of time each day in front of a computer it is important that the user-computer interface can be made as efficient and user-friendly as possible, so that the risk of fatigue and stress related problems are minimized. A key factor when creating an efficient computer environ- ment for an operator is enabling a relaxed and ergonomically appropriate working posture.

It is well known that the standard desktop mouse may cause stress injuries and Repetitive Strain Injuries (RSI). These problems can be explained by an unbalanced working posture resul- ting from the fact that the user repeatedly must reach out one of his/her hands to grasp and operate the mouse. Moreover, when manipulating the mouse, the angle between the lower arm and the hand and/or the angle of the shoulder joint (i.e. between the body and the upper arm) often becomes awkward. To improve this situation, various support means can be applied, for example in the form of lower arm supports or wrist rests, which may either be provided as separate units or be included in the pointer control device itself. Generally, it is most likely to obtain an ergonomically proper working posture if the user is allowed to hold his/her arms and hands straight in front of the body and as close to the body as possible, i.e. avoid having to reach out for a mouse, or equiva- lent pointer control device. Therefore, ideally, the pointer control device should be located in the area between the user and the keyboard (i.e. proximate to the user's abdomen). However, this table space is relatively limited, and a conventional desktop mouse cannot normally be operated here. Instead, an alternative solution is required.

A touchpad, which often is included a laptop, constitutes one means to accomplish a sufficiently small pointer control device. However, using a touchpad is associated with certain problems. For example, only one finger at the time can applied to the sen- sor surface. Otherwise, the pointer shows an unstable behavior on the display. Moreover, if the user changes from using one finger to another the pointer tends to jump abruptly across the display. Thus, it is complicated to use both hands, or to vary between a left and a right hand use.

An even more compact solution is shown in the US patent 6,057,540, which describes an optical position translation type of screen pointer control for a computer system, wherein images of a portion of the texture/fingerprint on one of a user's digits are registered repeatedly to generate the control signal to the computer system.

The International Patent Application WO2004/059613 discloses another cursor control device having a light source and an image sensor for optically tracking motion. Here, an upwardly facing dome, or window, provides a visual and tactical interface for user interaction. The user's hand, finger or other object controlled by the user may be moved in close proximity to the dome/window to produce the desired cursor control signal.

The published US patent application 2005/0062721 describes an optical pointer including a housing, a movable plate, a mani- pulable member and a displacement detecting unit. The movable plate is disposed in the housing and has a recognizable pattern. The manipulable member (or joystick) is manipulated by a user to transmit the movable plate to effect a two-dimensional movement inside the housing. The displacement detecting unit is disposed in the housing for optically detecting the recognizable pattern of the moveable plate, and generating a control signal indicative of a displacement of the movable plate according to detected image change of the recognizable pattern.

The above-mentioned prior solutions constitute examples of alternative pointer control means to the standard desktop mouse that may be advantageous in some aspects. However, each design is problematic from a user perspective for at least one of the following reasons: both hands cannot be used simultaneously to control the device; a change of hands/fingers causes an undesired pointer behavior; and for a typical sensitivity setting, several strokes over the sensor area may be required to move the pointer from one side of the display to the opposite side of the display.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a flexible pointer control device solution, which alleviates the problems above and thus enables a user to control a computer system based on information displayed on a display of the system while having a working posture that is ergonomically correct, and that also provides the user with a large degree of freedom in terms of how to manipulate the control device.

According to one aspect of the invention the object is achieved by the cursor control device as initially described, wherein the sensor surface is physically delimited by means of a boundary wall. The device also includes an actuator object that has an es- sentially flat actuator surface of a second area which is delimited by an object wall. The second area is smaller than the first area, and the object wall has such a configuration and such geometric proportions relative to a set of geometric proportions of the boundary wall that when the actuator object is placed on the sensor surface with the actuator surface facing the sensor surface and the actuator surface is positioned entirely within the boundary wall, the actuator object is slidable over the sensor surface. Moreover, a portion of the actuator object always co- vers at least one of the at least one sensor means.

An important advantage attained by this design is that, on one hand, the user may hold and manipulate the control device very freely (similar to the interaction with a standard desktop mouse), and on the other hand, the compactness, wrist support capa- bilities and well-defined operating surface conditions of a touch- pad are obtained.

According to a preferred embodiment of this aspect of the invention, the sensor surface has an essentially rectangular outline. Thereby, the sensor surface constitutes an intuitive representa- tion of the display over which the pointer is controlled. This in turn, further enhances the user friendliness.

According to a further preferred embodiment of this aspect of the invention, the object wall has such a configuration and such geometric proportions relative to the outline of the sensor surface that a symmetry point of the actuator object is slidable over a two-dimensional portion of the sensor surface, which has an aspect ratio approximately equal to an aspect ratio of a typical computer system display. Thereby, an even more intuitive linking between the pointer control device and the display is achieved.

According to another preferred embodiment of this aspect of the invention, the actuator surface has an essentially circular outline. This configuration is desirable because it allows an arbitra- ry rotation of the actuator object without influencing device's characteristics.

According to still another preferred embodiment of this aspect of the invention, at least one of the at least one sensor means includes a light source and a photodetection device adapted to register movements of the actuator object over the sensor surface. Such a sensor means is advantageous, since it enables a relatively compact design (i.e. physically slim), which in turn vouches for favorable ergonomic properties.

According to yet another preferred embodiment of this aspect of the invention, the device comprises one sensor means which is located centrally in the sensor surface. Thereby, for a smallest number of sensor means and a given sensor surface area, a smallest actuator object can be used. As a result, a largest range of movement over the sensor surface is potentially available.

According to a further preferred embodiment of this aspect of the invention, the device includes a resilient means linked to the sensor surface, and the sensor surface is resiliently movable relative to a device frame of the device in a direction essentially perpendicular to the sensor surface. The device also includes at least one sensor means that is adapted to register a movement of the sensor surface relative to the device frame of a particular magnitude. The device is adapted to produce a selection command in respect of at least one graphical object represented on the display in response to such a movement. Hence, during operation of the device, pushing the sensor surface downwards, either directly, or via the actuator object, can effect a so-called click command.

According to another preferred embodiment of this aspect of the invention, the device includes an adjustment means that is adapted to modify a resilient force that the resilient means exerts on the sensor surface to counteract said movement thereof relative to the device frame. In other words, the push force required to produce the selection command is adjustable.

According to still another preferred embodiment of this aspect of the invention, the boundary wall includes at least one sensor means adapted to register a contacting between the object wall and the boundary wall. Preferably, the device is further adapted to produce a particular type of control command in response to a registered contacting between the object wall and the boundary wall. The computer system can then be programmed to relocate the graphical pointer in response to the particular control command, so that the pointer reaches a display side equivalent to a side of the boundary wall which has made contact with the object wall. This has been found to be a very efficient means to avoid having to use several strokes when controlling the pointer's movement across the display.

According to yet another preferred embodiment of this aspect of the invention, the device includes at least one input member, which each is adapted to be manipulated by a user's finger and upon activation trigger a control signal in respect of a graphical object on the display. These input members may be programmed to accomplish a left-key-click function, a right-key-click function, a back-function, an escape-function etc.

According to a further preferred embodiment of this aspect of the invention, the device includes at least one input member, which each is rotatable and is adapted to produce a control signal realizing a sliding or a scrolling operation in respect of at least one graphical object on the display.

According to another preferred embodiment of this aspect of the invention, the actuator object has a manipulation surface oppo- site to the actuator surface, where the manipulation surface is essentially flat and essentially parallel to the actuator surface. This presents a simple and flexible surface for the user's fingers. The manipulation surface may also include at least one aperture, which each is adapted to receive a human fingertip. Namely, thereby the grip and fine control of the graphical pointer is further improved.

According to still another preferred embodiment of this aspect of the invention, the manipulation surface is essentially domed- shaped and has its convex side oriented away from the actuator surface. This type of surface provides an improved support for one or more of the user's fingers.

According to yet another preferred embodiment of this aspect of the invention, the manipulation surface includes a shaft means that is oriented essentially perpendicular to the actuator surface. Thereby, a high-precision pen grip is enabled, which is desirable in many applications.

According to a further preferred embodiment of this aspect of the invention, the actuator object also includes a joint means that connects the shaft means to the manipulation surface. The joint means permits flexion of the shaft means relative to the manipulation surface in at least one direction, so that approximately the same angle towards the user's fingers can be main- tained when the actuator object is slided over the sensor surface.

According to still another preferred embodiment of this aspect of the invention, the pointer control device is integrated into a support means, which is adapted to provide support for at least one of a user's wrists while operating the device. Thereby, an ergonomically efficient and user-friendly interface tool is provided.

To summarize, the invention offers a wide range of possibilities for the user of a computer, or other apparatus provided with a controllable display interface, to interact efficiently, accurately and in an ergonomically appropriate manner with the computer/ apparatus. The proposed device also provides a new flexibility in terms of the coordinate system based on which the graphical pointer is controlled on the display. Namely, by rotating the entire device by a particular angle, the coordinate system is rotated by the exact same angle. This is a desired feature in graphics and image processing software where a very high pointer control precision is required. Many times, the user may feel more comfortable with a particular offset angle between the coordinate system represented on the display (i.e. observed by his/her eyes) and the coordinate system of the pointer control device (i.e. controlled by his/her somatic nervous system).

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is now to be explained more closely by means of preferred embodiments, which are disclosed as examples, and with reference to the attached drawings.

Figure 1 shows a perspective top-view of a pointing device according to one embodiment of the invention,

Figure 2 schematically depicts a sensor surface and an actuator object according to a first embodiment of the invention,

Figure 3 shows a side-view of the pointing device in figure 1 ,

Figure 4 shows a perspective bottom-view of the pointing device in figure 1 ,

Figure 5 schematically depicts a sensor surface and an actuator object according to a second embodiment of the invention,

Figures 6a-f illustrate examples of actuator objects according to different embodiments of the invention, and

Figure 7 shows a perspective top-view of a proposed pointing device integrated into a wrist support means. DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Figure 1 shows a perspective top-view of a proposed pointing device 100 according to one embodiment of the invention. The device 100 adapted to produce control commands CmdP for influencing the position of a graphical pointer (i.e. a cursor, an arrow, a marker or other display indicator) on a computer system display. The term "computer system" should here be understood in a very broad sense, meaning any apparatus or arrange- ment including a controllable graphics processor, for example a receiver/decoder for television signals.

The device 100 includes an essentially flat sensor surface 1 10 and an actuator object 130. The sensor surface 110 includes a sensor means 120 that is adapted to register sliding movements of the actuator object 130 over the sensor surface 1 10. The device 100 generates the control commands CmdP in response to said movements.

The sensor surface 110 has a first area, which is physically delimited by means of a boundary wall 1 15. The actuator object 130 has an essentially flat actuator surface of a second area along whose periphery an object wall 135 is arranged, such that the actuator surface delimited by the object wall 135. The second area is smaller than the first area.

Furthermore, the object wall 135 has such a configuration and such geometric proportions relative to a set of geometric proportions of the boundary wall 115 that when the actuator object 130 is placed on the sensor surface 1 10 with the actuator surface towards the sensor surface 110, and the actuator surface is positioned entirely within the boundary wall 1 15, the actuator object 130 is slidable over the sensor surface 1 10. When positioned like this, a portion of the actuator object 130 always covers the sensor means 120.

According to embodiments of the invention, the sensor surface 110 has an essentially rectangular outline and the actuator object 130 has an essentially circular outline. However, according to the invention any alternative sensor surface 1 10 outlines and actuator object 130 outlines are conceivable, such as rectangular - rectangular, oval - circular and oval - rectangular.

In any case it is preferable if the boundary wall 1 15 comprises at least one sensor means 115a, 115b, 1 15c and 115d respectively, which is adapted to register a contacting between the object wall 135 and the boundary wall 1 15. The device 100 may then be adapted to produce a particular type of control command CmdP in response to a registered contacting between the object wall 135 and the boundary wall 115, so that for example irrespective of where the graphical pointer currently is located on the display, the pointer is relocated to a display edge equi- valent to a side of the boundary wall 1 15 which has made contact with the object wall. Specifically, activation of a topmost sensor means 115a will preferably place the pointer at the top edge of the display, activation of a rightmost sensor means 1 15b will preferably place the pointer at the right edge of the screen, activation of a bottommost sensor means 1 15c will preferably place the pointer at the bottom edge of the display, and activation of a leftmost sensor means 1 15d will preferably place the pointer at the left edge of the display. It is desirable that the computer system be programmed to move the pointer relatively quickly (however not instantly) to the relevant edge of the display in response to an activated sensor means 115a, 1 15b, 1 15c or/and 1 15d. Namely, this has been found to be a very efficient means to avoid having to use several strokes when controlling the pointer's movement across the display (i.e. lifting and back-positioning the actuator object 130 on the sensor surface 1 10).

Moreover, it is also preferable that the pointer movement over the display be recalibrated after that two opposing sensor means 1 15a and 1 15c; 1 15b and 1 15d respectively have been activated, such that a movement of the actuator object 130 from one boundary wall 1 15 segment to its opposing counterpart corresponds to a movement of the graphical pointer from a first edge of the display to an edge of the display being opposite to the first edge. Consequently, after having activated all the sen- sor means 115a, 1 15b, 115c and 1 15d the pointer movement on the display is fully calibrated in respect of the sensor surface 110.

According to one embodiment of the invention, the device 100 includes one or more input members that are adapted to be manipulated by a user's finger and upon activation of which a control signal is triggered in respect of a graphical object on the display. In figure 1 , three such input members are illustrated, and have been given reference numerals 141 , 142 and 145 respectively. For example, a first input member 141 may be pro- grammed to accomplish a left-key-click function, a second input member 142 may be programmed to accomplish a right-key-click function, and a third input member 145 may be programmed to accomplish a back-function or an escape-function.

The input members 141 , 142 and 145 may either be located along a particular side of a frame 160 of the device 100 (as shown in the figure 1 ), or be distributed over multiple sides of the frame 160 (see e.g. figure 7).

It may also be advantageous if the device 100 includes at least one input member 150, which each is rotatable and is adapted to produce a control signal realizing a sliding or a scrolling operation in a certain direction in respect of at least one graphical object on the display. Thereby, when interacting with certain software applications, the user interface is further improved. As an alternative, or complement, to the input member 150 the device 100 may include a button, a key and/or a tilt member which is adapted to produce the sliding/scrolling control signal.

Figure 2 schematically depicts the sensor surface 110 and the actuator object 130 according to a first embodiment of the inven- tion. The object wall 135 of the actuator object 130 here has such a configuration and such geometric proportions relative to the outline of the sensor surface 110 that a symmetry point 230 of the actuator object 130 is slidable over a two-dimensional portion 210 of the sensor surface 1 10, where the portion 210 has an aspect ratio VWR approximately equal to an aspect ratio of a typical computer system display. Hence, the aspect ratio W/R of the portion 210 preferably lies within an interval from 3/5 to 5/3 (i.e. 768/1280 to 1280/768), and most preferably W/R is around 4/3. For a circular-shaped actuator object 130 with a diameter of 50 mm, this aspect ratio may be provided by a sensor surface 110 being approximately 85 mm wide and approximately 75 mm high. Although these sizes are adequate for a majority of today's pointer control applications, any alter- native dimensions and proportions are feasible according to the invention.

The figure 2 shows a single sensor means 120 located centrally in the sensor surface 110. This configuration is advantageous because for a given sensor surface 1 10 area and a given ac- tuator object 130 area it allows a largest range of movement of the actuator object 130 over the sensor surface 1 10. Naturally, if the range of movement is a non-critical parameter, other sensor means 120 locations are conceivable.

The sensor means 120 can be based on any known movement detection technology, for instance based on a ball, discs, rollers, resistive and/or capacitive detection devices. However, preferably the sensor means 120 includes a light source and a pho- todetection device that are adapted to register movements of the actuator object 130 over the sensor surface 1 10. If such an opti- cal detector means 120 is used, the actuator surface is devised to have a non-uniform surface structure, so movements thereof can be discriminated by means of an image-based correlation process. Thus, the actuator surface includes some kind of pattern, either regular or irregular. Figure 3 shows a side-view of the pointing device 100 of figure 1. In this embodiment of the invention a resilient means 370 is linked to the sensor surface 1 10, such that the sensor surface 1 10 is resiliently movable relative to the frame 160 of the device 100 in a direction essentially perpendicular to the sensor surface 1 10.

The pointer control device 100 also includes one or more sensor means, here represented by 381 and 382, that are adapted to register a movement of the sensor surface 110 relative to the device frame 160 of a particular magnitude d. In response to a movement causing activation of at least one of the sensor means 381 and 382, the device 100 produces a selection command in respect of at least one graphical object represented on the display, typically object(s) located at, or in certain proximity to the graphical pointer's position on the display.

Preferably, an adjustment means is included in the device 100, which adjustment means is adapted to modify a resilient force that the resilient means 370 exerts on the sensor surface 110 to counteract a downward movement thereof relative to the device frame 160. The adjustment means is here symbolically by represented by a pair of protrusions 375a and 375b, which are attached to a rotatable disc. The protrusions 375a and 375b are manipulable from outside of the device 100, e.g. via slots in a bottom-side surface 360 of the device 100. Hence, by rotating the adjustment means in a first direction T the resilient force exerted by the means 370 on the sensor surface 1 10 is increased, and conversely by rotating the adjustment means in a second direction L the resilient force exerted by the means 370 on the sensor surface 1 10 is decreased. This is further illustra- ted in figure 4 showing a perspective bottom-view of the device 100.

According to one embodiment of the invention, the device 100 also includes a fastening mechanism (not shown), which is adapted to mechanically lock the sensor surface 110 relative to the frame 160, so that the sensor surface 1 10 cannot be moved as described above. Namely, some users may prefer a fix sensor surface 110, and instead perform any click functions via alternative means, e.g. the input members 141 , 142 and/or 145.

Figure 5 schematically depicts a sensor surface 1 10 and an actuator object 130 according to a second embodiment of the invention. Here, the sensor surface 110 includes two sensor means 121 and 122, which are located on separate sides of a center point 125 of the surface 1 10. Including multiple sensor means like 121 and 122 is desirable, since in order to enable motion detection it is then sufficient that the actuator object 130 always covers at least one of these means. Furthermore, if the sensor means 121 and 122 are located at such positions in the surface 110 that their mutual distances as well as their distances to boundary wall 1 15 are maximized (or at least made sufficiently large), a larger range of movement 210 of the actuator object 130 over the sensor surface 1 10 can be offered for a given sensor surface 110 area than if the surface 110 had included only one sensor means. Of course, this is an effect of that the actuator object 130 area can be made smaller.

Preferably, if one or more of the sensor means 121 and 122 include a light source, this device is automatically turned off as soon as it is detected that the sensor means in question is currently not covered by the actuator object 130. Thereby, potentially irritating light signals are prevented from reaching the user's eyes.

Figure 6a illustrates a first example of an actuator object 130 according one embodiment of the invention. Here, the actuator object 130 has a manipulation surface 130a located opposite to the actuator surface, wherein the manipulation surface 130a is essentially flat and essentially parallel to the actuator surface. This actuator object configuration is well adapted for a wide range of pointer control applications, such as word processing, surfing on the Internet etc. Figure 6b illustrates a second example of an actuator object 130 according one embodiment of the invention, wherein a manipulation surface 130b located opposite to the actuator surface is an essentially domed-shaped surface that has its convex side oriented away from the actuator surface. This design of the actuator object 130 is advantageous in that it provides good support for the user's fingers, and therefore can be operated for longer periods of time without causing fatigue related problems.

Figure 6c illustrates a third example of an actuator object 130 according one embodiment of the invention, wherein a manipulation surface 130a located opposite to the actuator surface includes a shaft means 130c that is oriented essentially perpendicular to the actuator surface. The shaft means 130c offers a pen grip, which facilitates a precise control of the graphical pointer on the display.

Figure 6d illustrates a fourth example of an actuator object 130 according one embodiment of the invention, wherein the manipulation surface 130b both is dome-shaped and includes a shaft means 13Od. This design generally combines the advantages of the embodiments shown in the figures 5b and 5c respectively.

Figure 6e illustrates a fifth example of an actuator object 130 according one embodiment of the invention, wherein the shaft means 13Oe connected to the manipulation surface 130a via joint means 13Oe'. The joint means 13Oe' is adapted to enable flexion of the shaft means 13Oe relative to the manipulation surface 130a in at least one direction. Thereby, the pen grip is further improved, so that an approximately constant angle towards the user's fingers can be maintained when the actuator object 130 is slided over the sensor surface 1 10.

Figure 6f illustrates a sixth example of an actuator object 130 according one embodiment of the invention, wherein the manipulation surface 130a includes at least one, say two, apertures 13Of 13Of , which each is adapted to receive a human fingertip. Such an outline is advantageous, since it enhances the grip and fine control of the graphical pointer. Additionally, a coordinate reference is provided for the user.

Naturally, it is apparent to the skilled person that according to the invention, in addition to the actuator object embodiments shown in the figures 6a to 6f, further combinations of the proposed manipulation surface elements 130a, 130b, 130c, 13Od, 13Oe, 13Of and 13Of are possible to achieve desired combined advantages of the control and support features described above.

Furthermore, the manipulation surface may have a larger area than the actuator surface being delimited by the object walls 135. For example, this means that the manipulation surface may include a board, plate or disc, which is even larger than the sensor surface 110. The board/plate/disc, in turn, may be equip- ped with one or more of the mechanical grip means described above with reference to the figures 6b to 6f.

Figure 7 shows a perspective top-view of a proposed pointing device 100, which is integrated into a wrist support means 700. The support means 700 is adapted to provide support for at least one of a user's wrists while he/she operates the device 100. To this aim the support means 700 may include a left support section 710 and a right support section 720 respectively.

Alternatively, according to other embodiments of the invention, the device 100 may be integrated into a keyboard, a so-called active mouse pad or a laptop computer. In the latter case, the device 100 may either be located in a frame portion of the computer between the built-in keyboard and the side of the unit facing the user, or it may be arranged in a slidable tray piece that can be pulled out towards the user from this side.

The term "comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components. However, the term does not preclude the presence or addition of one or more additional features, inte- gers, steps or components or groups thereof.

The invention is not restricted to the described embodiments in the figures, but may be varied freely within the scope of the claims.

Claims

1. A pointer control device (100) for producing control commands (CmdP) adapted to influence the position of a graphical pointer on a computer system display, the device (100) compri- sing an essentially flat sensor surface (110) having a first area, the sensor surface (110) including at least one sensor means (120; 121 , 122) adapted to register movements of a surface being slided over the sensor surface (1 10) and in response thereto generating the control commands (CmdP), characterized in that the sensor surface (1 10) is physically delimited by means of a boundary wall (115), and the device (100) further comprises an actuator object (130) having an essentially flat actuator surface of a second area delimited by an object wall (135), the second area being smaller than the first area, the object wall (135) having such a configuration and such geometric proportions relative to a set of geometric proportions of the boundary wall (1 15) that when the actuator object (130) is placed on the sensor surface (110) with the actuator surface facing the sensor surface (110) and the actuator surface is posi- tioned entirely within the boundary wall (1 15) the actuator object (130) is slidable over the sensor surface (1 10) and a portion of the actuator object (130) always covers at least one of the at least one sensor means (120; 121 , 122).

2. The pointer control device (100) according to claim 1 , cha- racterized in that the sensor surface (1 10) has an essentially rectangular outline.

3. The pointer control device (100) according to claim 2, characterized in that the object wall (135) has such a configuration and such geometric proportions relative to the outline of the sensor surface (110) that a symmetry point (230) of the actuator object (130) is slidable over a two-dimensional portion (210) of the sensor surface (1 10) having an aspect ratio (W/R) approximately equal to an aspect ratio of a typical computer system display.

4. The pointer control device (100) according to any one of the preceding claims, characterized in that the actuator surface has an essentially circular outline.

5. The pointer control device (100) according to any one of the preceding claims, characterized in that at least one of the at least one sensor means (120; 121 , 122) comprises a light source and a photodetection device adapted to register movements of the actuator object (130) over the sensor surface (110).

6. The pointer control device (100) according to any one of the preceding claims, characterized in that the device (100) comprises one sensor means (120) which is located centrally in the sensor surface (1 10).

7. The pointer control device (100) according to any one of the preceding claims, characterized in that the device (100) comprises a resilient means (370) linked to the sensor surface (110), sensor surface (110) is resiliently movable relative to a device frame (160) of the device (100) in a direction essentially perpendicular to the sensor surface (1 10), the device (100) comprises sensor means (381 ; 382) adapted to register a movement of the sensor surface (1 10) relative to the device frame (160) of a particular magnitude (d), and in response to such a movement produce a selection command in respect of at least one graphical object represented on the display.

8. The pointer control device (100) according to claim 7, characterized in that the device (100) comprises an adjustment means (375a, 375b) adapted to modify a resilient force that the resilient means (370) exerts on the sensor surface (1 10) to counteract said movement thereof relative to the device frame (160).

9. The pointer control device (100) according to any one of the preceding claims, characterized in that the boundary wall (1 15) comprises at least one sensor means (1 15a, 1 15b, 1 15c; 1 15d) adapted to register a contacting between the object wall (135) and the boundary wall (1 15).

10. The pointer control device (100) according to claim 9, characterized in that the device (100) is adapted to produce a particular type of control command (CmdP) in response to a registered contacting between the object wall (135) and the boundary wall (115).

11. The pointer control device (100) according to any one of the preceding claims, characterized in that the device (100) comprises at least one input member (141 , 142; 145) which each is adapted to be manipulated by a user's finger and upon activation trigger a control signal in respect of a graphical object on the display.

12. The pointer control device (100) according to any one of the preceding claims, characterized in that the device (100) comprises at least one input member (150) which each is rota- table and is adapted to produce a control signal realizing a sliding or a scrolling operation in respect of at least one graphical object on the display.

13. The pointer control device (100) according to any one of the preceding claims, characterized in that the actuator object (130) has a manipulation surface opposite to the actuator sur- face, and the manipulation surface comprises an essentially flat surface (130a) which is essentially parallel to the actuator surface.

14. The pointer control device (100) according to claim 13, characterized in that the manipulation surface (130a) compri- ses at least one aperture (13Of, 13Of) which each is adapted to receive a human fingertip.

15. The pointer control device (100) according to any one of the claims 1 to 12, characterized in that the manipulation surface comprises an essentially domed-shaped surface (130b) having its convex side oriented away from the actuator surface.

16. The pointer control device (100) according to any one of the claims 13 or 15, characterized in that the manipulation surface (130a) comprises a shaft means (130c, 13Od; 13Oe) oriented essentially perpendicular to the actuator surface.

17. The pointer control device (100) according to claim 16, characterized in that the actuator object (130) comprises a joint means (13Oe') connecting the shaft means (13Oe) to the manipulation surface, and the joint means (13Oe') is adapted to enable flexion of the shaft means (13Oe) relative to the manipulation surface (130a) in at least one direction.

18. The pointer control device (100) according to any one of the preceding claims, characterized in that the device (100) is integrated into a support means (700) which is adapted to provide support for at least one of a user's wrists while operating the device (100).