Skin treatment system

Abstract

To provide a skin treatment system enabling determination about adjusting a way of using the skin treatment system by providing a user with information during a skin treatment action.SOLUTION: A skin treatment system 1 is provided, comprising: a functional member 20 that is configured to perform a treatment action on skin 2 and to be moved over the skin 2 during operation of the system 1; and a measurement unit 40 including a measurement member 41 that is configured to also be moved over the skin 2 during operation of the functional member 20 and to contact the skin 2 during a process. The measurement unit 40 is configured to measure at least a force value in an advancing direction in which the measurement member 41 is moved over the skin 2 during operation of the functional member 20. The measured force value in the advancing direction is used for the purpose of determining a friction coefficient value representative of the friction coefficient of the skin 2, which allows for assessing a skin condition.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a skin treatment system that includes a functional member that performs a treatment action on the skin and moves over the skin during operation of the system. [Background technology]

[0002] An example of the skin treatment system described in the opening paragraph is a hair removal system for performing skin treatment in the form of removing hair from the skin. The system includes an epilation body as a functional member. In conventional designs, the epilation body is usually shaped like a cylinder with a circular periphery. The epilation body is rotatable around a rotation axis extending in the longitudinal direction of the epilation body. The functional member can be held in a curved configuration. Furthermore, the epilation body is provided with at least one hair-capturing space, the longitudinal size of which is variable along the periphery of the epilation body or by compression and expansion of the epilation body in the longitudinal direction during the rotation of the epilation body. The operation of the epilation system for removing hair from the skin involves driving the epilation body to rotate with the epilation body placed on the skin, and rotating the epilation body body on the skin, whereby hair is captured in the at least one hair-capturing space as the size of the at least one hair-capturing space decreases and is pulled out of the skin as the epilation body advances.

[0003] In the context of a skin treatment system, such as a hair removal system, the process of performing a skin treatment action may have skin irritation as an undesirable side effect. In the example of a hair removal system, skin irritation may occur from the continuous friction of the hair removal body rolling over the skin during operation of the hair removal system. Furthermore, hairs protruding from the skin may be pulled, causing bumps and irritated spots, altering the properties of the skin surface. Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the above, it is desirable to provide a reliable way of determining skin characteristics during a skin treatment action performed by a skin treatment system, which allows at least one of the following possibilities: providing a user of the skin treatment system with relevant information about the skin's condition and automatically adjusting the way in which one or more components of the skin treatment system are operated. Providing information to the user can be performed during and / or after the skin treatment action. Providing information to the user during the skin treatment action allows the user to decide on an adjustment in the way the skin treatment system is used. On the other hand, providing information to the user after the skin treatment allows the user to first become aware of the condition of his / her skin and to decide on possible further skin treatment actions, such as applying a soothing cream to the skin. It should be noted that the possibility of automatically adjusting the way in which one or more components of the skin treatment system are operated is particularly aimed at preventing a further increase in skin irritation, for example if it is found that the level of skin irritation exceeds an acceptable reference level. [Means for solving the problem]

[0005] In view of the above, the present invention provides a skin treatment system including a functional member that performs a treatment action on the skin and moves over the skin during operation of the skin treatment system, a measuring unit including a measuring member that moves over the skin during operation of the functional member and contacts the skin during the process, the measuring unit obtaining at least one measured force value by measuring at least one force value related to an interaction between the measuring member and the skin, the at least one measured force value including a force value in an advancing direction in which the measuring member moves over the skin during operation of the functional member, and a processor unit that receives the at least one measured force value from the measuring unit and determines a friction coefficient value representing a friction coefficient of the skin based on at least the measured force value in the advancing direction.

[0006] From the above definitions, it can be seen that the skin treatment system according to the invention includes, in addition to the functional member, a measuring unit and a processor unit. During the operation of the skin treatment system, the measuring unit measures a force value in the forward direction, i.e. in the direction of movement of the measuring member on the skin, and possibly one or more other force values ​​related to the interaction of the measuring member with the skin. The input obtained from the measuring unit is used by the processor unit during the process of determining a friction coefficient value representative of the friction coefficient of the skin. The functional unit and the measuring unit may be incorporated in a handheld appliance. In this case, the processor unit may be a remote unit outside the handheld appliance. This does not change the fact that the invention also covers other options. The treatment action on the skin may be one of, for example, brushing the skin or removing hair by epilation. It is noted that the invention is not limited to a specific type of skin treatment.

[0007] According to the findings on which the present invention is based, the coefficient of friction of the skin is related to aspects of the skin condition (such as wetness, elasticity and roughness), i.e. skin-related characteristics. Determining a coefficient of friction value representative of the coefficient of friction of the skin has been found to be useful in assessing the condition of the skin. By implementing the present invention, an objective indication of the skin condition is obtained. The measurement is obtained during the skin treatment procedure, without the need for a separate measurement treatment procedure.

[0008] In the framework of the present invention, various options are applicable regarding the manner of determining the friction coefficient value. According to a first option, the processor unit determines the friction coefficient value by dividing the measured force value in the forward direction by a reference force value. For example, the reference force value is a value representative of the average force when the user presses the functional unit against the skin. According to a second option, the measurement unit also measures a normal force value of the contact of the measuring member on the skin, and the processor unit determines the friction coefficient value by dividing the measured force value in the forward direction by the measured value of the normal force. According to a third option, the skin treatment system further comprises an arrangement part enabling adjustment of the normal force of the contact of the measuring member on the skin, and the processor unit receives from the arrangement part a normal force value set by the arrangement part and determines the friction coefficient value by dividing the measured force value in the forward direction by the set normal force value.

[0009] In an advantageous embodiment of the skin treatment system according to the invention, the processor unit further determines whether the coefficient of friction value is within a reference range of coefficient of friction values, for example the reference range of coefficient of friction values ​​being one of: i) a range between a minimum and a maximum coefficient of friction value, and ii) a range above or below a single identified coefficient of friction value. It is practical if the reference range of coefficient of friction values ​​is a range of coefficient of friction values ​​associated with a skin-related feature, which may be one of a group of features including wetness, elasticity, and roughness.

[0010] By having the capability of determining whether the coefficient of friction value is within a reference range of coefficient of friction values ​​in the skin treatment system, the skin treatment system can be used to provide skin condition information to a user. It can also provide appropriate suggestions to the user on how to further treat the skin. In this regard, it is practical if the skin treatment system further includes a display device and the processor unit further provides an output regarding the skin-related characteristic to the display device.

[0011] As mentioned above, it is desirable to have the possibility to automatically adjust the way in which one or more components of the skin treatment system operate. In view of the above, it is practical if the skin treatment system according to the invention further comprises a control unit for controlling the operation of the functional member, and the processor unit further determines at least one parameter of the operation of the functional member based on the friction coefficient value and provides an output to the control unit regarding the at least one parameter of the operation of the functional member. For example, if the skin treatment system is a hair removal system, the at least one parameter of the operation of the functional member comprises a rotation speed of the hair removal body. Generally, in such a case, the control method of the operation of the hair removal system is realized by the rotation speed of the hair removal body being reduced when the friction coefficient value indicates a high level of skin irritation. According to another possible option, the at least one parameter of the operation of the functional member comprises the extent to which the hair removal body is extended relative to a housing part supporting the hair removal body or the like. Generally, in such a case, the control method of the operation of the hair removal system is realized by the hair removal body being further retracted relative to the housing part when the friction coefficient value indicates a high level of skin irritation.

[0012] The present invention is directed to any suitable embodiment of the measurement unit. For example, it may be practical if the measurement unit includes an elastic member acting on the measurement member. An example of such an elastic member is a coil spring. It may also be practical if the skin treatment system obtains more measurements than at least one force value related to the interaction of the measurement member with the skin. For example, the skin treatment system further includes at least one of a position sensor, a velocity sensor, and an acceleration sensor associated with the measurement member.

[0013] According to an advantageous option present within the framework of the invention, the measuring member may comprise two regions positioned on either side of the measuring member and having differently shaped contours, in this way, depending on the direction of movement of the measuring member on the skin, different interactions of the measuring member with the skin can be realised, on the basis of which reliable measurement results can be obtained for different skin-related characteristics.

[0014] An embodiment of the skin treatment system according to the invention is feasible, in which the measuring unit further comprises at least one additional measuring member which moves over the skin during the operation of the functional member and contacts the skin during the process. The measuring unit obtains the at least one additional measured force value by measuring at least one force value related to the interaction of the at least one additional measuring member with the skin. In this way, the accuracy of the process of determining the friction coefficient value representative of the friction coefficient of the skin can be increased, since the influence of factors such as the orientation of the measuring member is reduced.

[0015] These and other aspects of the invention will become apparent from and elucidated with reference to the following detailed description of a hair removal system including a measurement unit. Various possibilities for the configuration of the measurement unit and its components are addressed. [Brief description of the drawings]

[0016] The invention will now be explained in more detail with reference to the figures, in which the same or similar parts are designated by the same reference numerals.

[0017] [Figure 1] FIG. 1 illustrates a front view of a handheld hair removal device that is part of a hair removal system according to an embodiment of the present invention. [Diagram 2] FIG. 2 illustrates the epilation body, the housing part supporting the epilation body, the measurement unit, the processor unit, the control unit and the display device of the epilation system. [Diagram 3] FIG. 3 shows a first possible configuration of the measurement unit. [Figure 4] FIG. 4 shows a second possible configuration of the measurement unit. [Diagram 5] Fig. 5 shows the interaction of the skin with the measuring member of the measuring unit, which includes two regions with differently shaped profiles positioned on either side of the measuring member for two opposite directions of movement of the epilating body along the skin. [Figure 6]Fig. 6 shows the interaction of the skin with the measuring member of the measuring unit, which includes two regions with differently shaped profiles positioned on either side of the measuring member for two opposite directions of movement of the epilating body along the skin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In the following, various features of the hair removal system 1 according to an embodiment of the present invention will be described. It should be noted that the hair removal system 1 is one example of many types of skin treatment systems that can be realized within the framework of the present invention. Furthermore, with reference to Fig. 1, it should be noted that the hair removal system 1 is practical when it includes a handheld appliance 10. The handheld appliance 10 includes a housing 11 that houses a number of components of the hair removal system 1. The use of the handheld appliance 10 allows the hair removal system 1 to be conveniently used on various body areas such as the face, underarms, and legs.

[0019] The epilation system 1 is used to perform a hair removal operation on the skin. With that in mind, the epilation system 1 comprises an epilation body 20 intended to actually interact with the hair to be plucked from the skin. To capture and grip the hair, the epilation body 20 comprises hair clamping members 21 with a hair capture space 22 therebetween. In the illustrated example, the epilation body 20 is shaped like a cylinder having a generally circular periphery. The epilation body 20 is rotatable about a rotation axis R extending in the longitudinal direction of the epilation body. The longitudinal size of the hair capture space 22 is variable along the periphery of the epilation body 20. It will be appreciated that the epilation system 1 comprises components such as a drive mechanism (not shown) for driving the epilation body 20 to actually perform a rotational movement about the rotation axis R during operation of the epilation system 1, and a power supply arrangement (not shown), such as a (rechargeable) battery in case the handheld appliance 10 is cordless.

[0020] As shown in Fig. 2, it is practical if the epilation system 1 further comprises a control unit 30 for controlling the operation of the epilation body 20. A suitable user interface 31, such as a button, is provided on the housing 11 of the handheld appliance 10 to enable the user to activate and deactivate the epilation system 1. When the epilation system 1 is activated, the epilation body 20 is driven to rotate. The skin 2 that is subjected to the epilation action by the epilation system 1 is shown in Figs. 1 and 2 by dashed lines. To properly use the epilation system 1, it is necessary to activate the epilation system 1 and move the handheld appliance 10 so that the epilation body 20 rotates on the skin 2. In this process, hair is captured in the hair capture space 22 of the epilation body 20 and is pulled out from the skin 2 as the epilation body 20 advances.

[0021] 2 also shows that the epilation system 1 further comprises a measuring unit 40 and a processor unit 50. The measuring unit 40 comprises a probe-like measuring member 41 which moves over the skin 2 together with the epilation body 20 during the operation of the epilation body 20 and comes into contact with the skin 2 during the above process. The measuring member 41 measures a force value in a forward direction in which the measuring member 41 moves over the skin 2 during the operation of the epilation body 20 and possibly at least one other force value related to the interaction of the measuring member 41 with the skin 2. For the sake of completeness, it is noted that the force in the forward direction is a force related to friction and has an opposite sign to the forward direction. During the operation of the epilation system 1, the measuring unit 40 outputs the measured force value in the forward direction and possibly at least one other measured force value to the processor unit 50, which determines a friction coefficient value representative of the friction coefficient of the skin 2 based at least on the measured force value in the forward direction.

[0022] The processor unit 50 may be configured in a suitable manner to determine the coefficient of friction value. For example, the coefficient of friction value can be determined by dividing the measured force value in the forward direction by a reference force value. It is also possible to determine the coefficient of friction value by measuring or setting a normal force value of the contact of the measuring member 41 with the skin 2 and dividing the measured force value in the forward direction by the measured or set normal force value. In any case, an important advantage of the present invention is that the skin friction measurement can be performed during the hair removal process, without the need for a separate measurement.

[0023] The information about the coefficient of friction of the skin 2 is suitable for use in a process of evaluating one or more skin-related features constituting an aspect of the condition of the skin 2. For example, an indication of the wetness, elasticity and / or roughness of the skin 2 can be obtained from the coefficient of friction value. As mentioned above, the processor unit 50 further determines whether the coefficient of friction value is within a reference range of coefficient of friction values, so as to be able to perform at least one step in the skin condition evaluation process. Assuming that the reference range of coefficient of friction values ​​is a range of coefficient of friction values ​​associated with the skin-related feature, it is advantageous if the epilation system 1 further comprises a display device 32 and if the processor unit 50 is further configured to provide an output on the display device 32 regarding the skin-related feature so that the user is informed via the display device 32. It is also advantageous if the processor unit 50 is further configured to determine at least one parameter of the operation of the epilation body 20 based on the coefficient of friction value and to provide an output regarding the at least one parameter to the control unit. In this case, a self-regulation function of the epilation system 1 is realized. For example, if the friction coefficient value indicates a high level of skin irritation, the processor unit 50 provides an output to the control unit 30 regarding the rotation speed of the epilation body 20. Specifically, the output is aimed at reducing the rotation speed.

[0024] 2, dashed lines indicate the exchange of signals between the processor unit 50 and the control unit 30, the display device 32 and the measurement unit 40. The processor unit 50 and the display device 32 may be housed in the handheld appliance 10, although it is also practical if at least one of the processor unit 50 and the display device 32 is located outside the handheld appliance 10.

[0025] A first option for the configuration of the measuring unit 40 will be described in detail with reference to FIG. 3. The forward direction in which the measuring member 41 moves on the skin 2 during the operation of the epilation body 20 is indicated by the arrow A in the upper part of FIG. 3. Furthermore, in FIG. 3, the direction along the skin 2 is indicated as the X direction, and the normal direction of the skin is indicated as the Y direction. Besides the measuring member 41, the measuring unit 40 comprises a load cell 42 for measuring the force value in the forward direction A, and a spring 43 for creating a spring force on the measuring member 41. The load cell 42 is in particular arranged to deform under the influence of a force acting in the forward direction A. As is known from the field of load cells, it is practical to use amplification hardware in order to convert the change in the electrical resistance of the load cell 42 caused by the deformation of the load cell 42 into an electrical signal. The electrical signal is therefore directly related to the value of the force acting in the forward direction A.

[0026] The way in which the measuring unit 40 configured according to the first option described above works is as follows: the measuring unit 40 can perform measurements of the force values ​​in the forward direction A as the epilation body 20 advances over the skin 2 in the forward direction A, the measuring member 41 automatically performing the same movement. At the position where the measuring member 41 contacts the skin 2, forces prevail in both the X and Y directions, namely a traction force F in the X direction and a normal force N in the Y direction. The traction force F is related to the friction between the measuring member 41 and the skin 2, while the normal force N is determined by the spring 43. The traction force F is influenced by the properties of the measuring member 41 at the position of contact with the skin 2, such as shape, material and surface features. Such properties can therefore be selected to optimize the measurement process as required. By applying a relatively high pretension in the spring 43, combined with a relatively low spring constant, the spring force is only slightly influenced by changes in the press-in of the measuring member 41, whereby a quasi-constant value of the normal force N is achieved.

[0027] Overall, when the hair removal system 1 is equipped with a measuring unit 40 configured according to the first option described above, the friction coefficient value can be determined by the processor unit 50 by dividing the measured traction force F value by the spring force value.

[0028] For example, the spring 43 can be omitted from the measuring unit 40 if it is equipped with a separate load cell 44, as shown in FIG. 4. FIG. 4 relates to a second option for the configuration of the measuring unit 40. In particular, the load cell 44 is arranged and configured to deform under the influence of a normal force N. In such a case, the friction coefficient value can be determined by the processor unit 50 by dividing the value of the measured traction force F by the value of the measured normal force N. A further option allowing the spring 43 to be omitted is an option with the opportunity for the user to set the value of the force to be applied to the measuring member 41 in the Y direction. On the other hand, the use of the spring 43 in combination with the normal force load cell 44 is possible. In particular, if the spring constant is known, the output provided by the normal force load cell 44 in this case can indicate the angle of the handheld appliance 10 to the skin 2. In the case of the hair removal system 1, this is particularly advantageous, since the effectiveness of the use of the system 1 is related to the aforementioned angle.

[0029] With reference to Figures 5 and 6, an option is described to design the measuring member 41 to include two regions 45, 46 positioned on either side of the measuring member 41 and having differently shaped profiles. In Figures 5 and 6, the skin 2 and a portion of the measuring member 41 including the regions 45, 46 are shown. For illustrative purposes, the regions 45, 46 are shown as being extremely different, one region 45 including a curved edge zone and the other region 46 including an acute edge zone with two straight zones connected at a 90° angle to each other. When the measuring member 41 is moved in a forward direction A with the region 45 including the curved edge zone in front, there is almost no doming of the skin 2 in front of the measuring member 41, as shown in Figure 5. In this way, a force measurement can be made that is related to the surface features of the skin 2. It should be noted that the roughness of the skin 2, the presence of sebum on the skin 2, and the use of personal care products on the skin 2 are examples of such surface features. Moving the measuring member 41 in a forward direction A with a region 46 including a sharp edge zone in front of it leads to a so-called "ploughing" effect, as shown in Figure 6, which results in the skin 2 folding up against the measuring member 41. In this way force measurements can be made which relate to the elasticity of the skin 2 and to deeper skin tissue characteristics.

[0030] In an additional or alternative option, the hair removal system 1 may be provided with a set of at least two interchangeable measuring members 41 of different designs, thereby allowing a user to select the most suitable measuring member 41 taking into account one or more relevant types of skin-related characteristics.

[0031] Further information regarding the use of the epilation system 1 can be obtained if the epilation system 1 is equipped with one or more sensors, such as an accelerometer. Combining an accelerometer with the components used for skin friction measurement improves the accuracy of the skin friction measurement. Firstly, the accelerometer can be used to assess whether the measuring member 41 is correctly positioned on the skin 2. If not, feedback can be provided to the user to allow him to correct the positioning of the measuring member 41. Secondly, it is known that friction has a static and a dynamic aspect, and therefore the friction of the skin surface depends on the movement. The accelerometer can be used to detect the movement and determine the speed of movement. Secondly, the accelerometer or another type of positioning sensing device can be used to assess which body part the measuring member 41 is being used on. It is important to have such information, since it is known that the friction of the skin surface varies for different body parts, and if the actual body part is known, the measured force value in the forward direction A can be appropriately corrected.

[0032] It will be apparent to those skilled in the art that the scope of the present invention is not limited to the above examples, and that some amendments and modifications are possible without departing from the scope of the present invention as defined in the appended claims. It is intended that the present invention be construed as including all such amendments and modifications insofar as they come within the scope of the claims or their equivalents. While the present invention has been illustrated and described in detail in the drawings and description, such illustration and description should be considered as illustrative or exemplary only, and not restrictive. The present invention is not limited to the disclosed embodiments. The drawings are schematic, and details not necessary for understanding the present invention may be omitted, and are not necessarily drawn to scale.

[0033] Variations of the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the figures, the disclosure, and the appended claims. In the claims, the word "comprises" does not exclude other steps or elements, and the singular does not exclude a plurality. Any reference signs in the claims should not be construed as limiting the scope of the invention.

[0034] Elements and features described with respect to or in connection with a particular embodiment can be combined with elements and features of the other embodiments as appropriate, unless expressly stated otherwise. Thus, the mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0035] The terms "having" and "including" as used in this text will be understood by those skilled in the art as encompassing the term "consisting of." Thus, the terms "having" or "including" may mean "consisting of" in the context of one embodiment, but in another embodiment may mean "containing / having / comprising at least the defined species and optionally one or more other species."

[0036] An important aspect of the invention is the following: A skin treatment system 1, such as a hair removal system, comprises a functional member 20 which performs a treatment action on the skin 2 and which moves over the skin 2 during operation of the system 1, and a measurement unit 40 which comprises a measurement member 41 which moves over the skin 2 during operation of the functional member 20 and comes into contact with the skin 2 during the process. The measurement unit 40 measures at least a force value in an advance direction A in which the measurement member 41 moves over the skin 2 during operation of the functional member 20. The measured force value in the advance direction A is used for the purpose of determining a friction coefficient value representative of the friction coefficient of the skin 2, so that the condition of the skin 2 can be assessed.

Claims

1. 1. A skin treatment system comprising: a functional member that performs a treatment action on the skin and moves over the skin during operation of the skin treatment system; a measuring unit including a measuring member that moves over the skin during operation of the functional member and contacts the skin during the process, and obtains at least one measured force value by measuring at least one force value related to an interaction of the measuring member with the skin, the at least one measured force value including a force value in a forward direction in which the measuring member moves over the skin during operation of the functional member; a processor unit for receiving the at least one measured force value from the measurement unit and for determining a friction coefficient value representative of a friction coefficient of the skin based on at least the measured force value in the forward movement direction; A skin treatment system comprising:

2. The skin treatment system of claim 1 , wherein the processor unit determines the coefficient of friction value by dividing the measured force value in the forward direction by a reference force value.

3. 2. The skin treatment system of claim 1, wherein the measurement unit also measures a normal force value of contact of the measurement member with the skin, and the processor unit determines the coefficient of friction value by dividing the measured force value in the forward direction by the measured value of the normal force.

4. 2. The skin treatment system of claim 1, further comprising an arrangement enabling adjustment of a normal force of contact of the measuring member on the skin, wherein the processor unit receives from the arrangement a value of the normal force set by the arrangement and determines the coefficient of friction value by dividing the measured force value in the forward direction by the set normal force value.

5. The skin treatment system of claim 1 , wherein the processor unit is further configured to determine whether the coefficient of friction value is within a reference range of coefficient of friction values.

6. 6. The skin treatment system of claim 5, wherein the reference range of coefficient of friction values ​​is one of: i) a range between a minimum and a maximum coefficient of friction value; and ii) a range above or below a single discriminatory coefficient of friction value.

7. The skin treatment system of claim 5 or 6, wherein the reference range of coefficient of friction values ​​is a range of coefficient of friction values ​​associated with skin-related features.

8. The skin treatment system of claim 7 , wherein the skin-related characteristic is one of a group of characteristics including wetness, elasticity, and roughness.

9. The skin treatment system of claim 7 or 8, further comprising a display device, the processor unit further being adapted to provide output relating to the skin-related characteristics to the display device.

10. 10. The skin treatment system of claim 1, further comprising a control unit for controlling the operation of the functional member, the processor unit further determining at least one parameter of the operation of the functional member based on the friction coefficient value and providing an output to the control unit regarding the at least one parameter of the operation of the functional member.

11. The skin treatment system according to claim 1 , wherein the measurement unit includes an elastic member acting on the measurement member.

12. The skin treatment system of claim 1 , further comprising at least one of a position sensor, a velocity sensor, and an acceleration sensor associated with the measurement member.

13. 13. The skin treatment system of claim 1, wherein the measurement member includes two regions positioned on either side of the measurement member and having different shaped contours.

14. 14. The skin treatment system of claim 1, wherein the measuring unit further comprises at least one additional measuring member that moves over the skin during operation of the functional member and contacts the skin during the process, and the measuring unit obtains at least one additional measured force value by measuring at least one force value associated with an interaction of the at least one additional measuring member with the skin.

15. The skin treatment system of claim 1 , wherein the functional unit and the measurement unit are integrated within a handheld appliance, and the processor unit is a remote unit external to the handheld appliance.

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