Treatment device using R.F. electrical current for heating a first inner region and a second inner region of skin

Abstract

The invention provides a non-invasive treatment device (100) for heating a first (15) and a second (25) inner region of skin using r.f. electrical current, comprising: a first r.f. treatment electrode (10) configured and arranged to allow r.f. current to pass through the first inner region (15) to a return electrode (340), a second r.f. treatment electrode (20) configured and arranged to allow r.f. current to pass through the second inner region (25) to the return electrode (340), the device further being arranged such that the smallest distance between the first r.f. treatment electrode (10) and the return electrode (340) is less than the smallest distance between the second r.f. treatment electrode (20) and the return electrode (340); wherein the electrical skin contact area of the return electrode (340) is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode (10), and the electrical skin contact area of the second r.f. treatment electrode (20) is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode (10). By incorporating the second and first treatment electrodes in the same device, or probe, the positional relationship between the first and second regions being heated is fixed, or at least more predictable. By means of a suitable configuration, the regions may coincide to a smaller or greater degree. In some cases, the configuration may allow the same skin condition to be treated using heating of the first and second inner regions without moving the device over the skin. By providing an electrical skin contact area of the return electrode which is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode, the locations heated by the r.f. electrical current will be proximate to the first treatment electrode, reducing the possibility of undesirable hotspots proximate the return electrode (340).

Claims

1. A non-invasive treatment device for heating a first inner region and a second inner region of skin using radio-frequency (r.f.) electrical current, the second inner region being at a deeper location in the skin than the first inner region, the device comprising: a first r.f. treatment electrode configured and arranged to allow r.f. electrical current to pass through an outer surface of the skin and through the first inner region; a return electrode configured and arranged to allow r.f. electrical current to pass through the first inner region and the outer surface of the skin, wherein the return electrode is used in combination with the first r.f. treatment electrode for a skin rejuvenation treatment; a first r.f. generator configured and arranged such that, in use for heating the first inner region, a first r.f. current is applied through the first inner region between the first r.f. treatment electrode and the return electrode operating in bipolar mode; a second r.f. treatment electrode configured and arranged to allow r.f. electrical current to pass through the outer surface of the skin and through the second inner region; the return electrode being further configured and arranged to allow r.f. electrical current to pass through the second inner region and the outer surface of the skin, wherein the return electrode is used in combination with the second r.f. treatment electrode for a skin tightening treatment; and a second r.f. generator configured and arranged such that, in use for heating the second inner region, a second r.f. current is applied through the second inner region between the second r.f. treatment electrode and the return electrode operating in bipolar mode; wherein a smallest distance between the first r.f. treatment electrode and the return electrode is less than a smallest distance between the second r.f. treatment electrode and the return electrode; wherein the first r.f. treatment electrode, the second r.f. treatment electrode and the return electrode each comprise an electrical skin contact area, a maximum dimension of the first r.f. treatment electrode proximate the electrical skin contact area of the first r.f. treatment electrode being less than or equal to 1 mm, and the electrical skin contact area of the return electrode being 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode, wherein, for skin rejuvenation, a skin region effectively heated by the first r.f. electrical current will be at a first treatment target proximate to, immediately below, the first r.f. treatment electrode while reducing a possibility of undesirable hotspots proximate to the return electrode, wherein the electrical skin contact area of the second r.f. treatment electrode is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode, wherein, for skin tightening, a skin region effectively heated by the second r.f. electrical current will be at a second treatment target intermediate the second r.f. treatment electrode and the return electrode; the device further comprising: a controller to selectively activate the first r.f. generator and the second r.f. generator either separately or alternately for applying both skin rejuvenation and skin tightening treatments at a same position of the treatment device on the skin.

2. The treatment device according to claim 1, wherein, when the treatment device is in operation for heating the first inner region, the second r.f. treatment electrode is configured and arranged as a further return electrode to allow r.f. electrical current to pass through the first inner region and the outer surface of the skin, and wherein the first r.f. generator is configured and arranged such that an r.f. electrical current is applied between the first r.f. treatment electrode and both the return electrode and the further return electrode through the first inner region, and wherein a total of the electrical skin contact areas of the return electrode and the further return electrode is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode.

3. The treatment device according to claim 1, wherein the device comprises a plurality of first r.f. treatment electrodes, the plurality of first r.f. treatment electrodes and the return electrode being configured and arranged to allow r.f. electrical current to pass through the outer surface of the skin and through a plurality of first inner regions, and wherein the first r.f. generator is configured and arranged to apply r.f. electrical current to each of the plurality of first r.f. treatment electrodes and to each of the plurality of first inner regions either alternately or simultaneously.

4. The treatment device according to claim 1, wherein the device comprises a plurality of second r.f. treatment electrodes, the plurality of second r.f. treatment electrodes and the return electrode being configured and arranged to allow r.f. electrical current to pass through the outer surface of the skin and through a plurality of second inner regions, and wherein the second r.f. generator is configured and arranged to apply r.f. electrical current to each of the plurality of second r.f. treatment electrodes and to each of the plurality of second inner regions either alternately or simultaneously.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 diagrammatically shows a first embodiment 300 of a non-invasive treatment device according to the invention in use when treating skin,

(2) FIG. 2 shows a second embodiment 400 of the non-invasive treatment device according to the invention in use when providing a first r.f. electrical current to a first inner region of the skin,

(3) FIGS. 3A-3D depict four examples of electrode geometries and configurations comprising a single first r.f. treatment electrode, and

(4) FIGS. 4A-4D depict four examples of electrode geometries and configurations comprising a plurality of first r.f. treatment electrodes and two further electrodes.

(5) It should be noted that items which have the same reference numbers in different Figures have the same structural features and the same functions, or represent similar signals. Where the function and/or structure of such an item has been explained, there is no necessity for repeated explanation thereof in the detailed description.

DETAILED DESCRIPTION OF EMBODIMENTS

(6) FIG. 1 schematically shows a first embodiment of a non-invasive skin treatment device 300 comprising a first r.f. treatment electrode 10, a return electrode 340, and a second r.f. treatment electrode 20, each of which have an electrical skin contact area. The device 300 further comprises a first r.f. generator 18 configured and arranged to be operated in bipolar mode by being electrically connected to the first r.f. treatment electrode 10 and the return electrode 340.

(7) The device 300 also comprises a second r.f. generator 28, configured and arranged to be operated in bipolar mode by being electrically connected to the second r.f. treatment electrode 20 and the return electrode 340. The return electrode 340 is configured and arranged to allow electrical current to pass through both the first inner region 15 and the second inner region 25 of the skin and an outer surface of skin. The second r.f. generator 28 is configured and arranged such that, in use for heating, an r.f. current is applied between the second r.f. treatment electrode 20 and the combined return electrode 340 through the first inner region 15.

(8) The device may have two distinct r.f. generators, or a single r.f. generator configured to provide both the first r.f. current and the second r.f. current during, respectively, the first and second use. For example, for simultaneous application of the first r.f. current and the second r.f. current, a single transformer may be used with potential tapping having an approximately 1:2 voltage ratio (e.g. 40 V for second r.f. current and 80 V for first r.f. current). The device 300 further comprises a controller 30, electrically connected to the first r.f. generator 18 and the second r.f. generator 28, and configured and arranged to selectively activate the first 18 and second r.f. generators either simultaneously, separately or alternately.

(9) The device 300 is configured and arranged to be brought into close proximity of human or animal skin 60, with the treatment electrodes 10, 20 and the return electrode 340 facing the outer layer of the skin. Each electrode comprises a skin contact area, which provides electrical contact with the skin 60 during use of that electrode. The treatment and return electrodes may make physical contact with the outer layer of the skin, or may be arranged at a small distance from the skin with a small gap between the electrodes and the skin. Typically, a conductive substance, such as a gel, is applied in this gap between the skin and the skin contact area to reduce any contact impedance between electrodes and the outer layer of the skin.

(10) The treatment device 300 is configured and arranged to heat the first inner region 15 and the second inner region 25 of the skin using r.f. current the first inner region 15 is substantially smaller in volume than the second inner region 25. This is determined, inter alia, by the arrangement and configuration of the treatment electrodes 10, 20 and the return electrode 340, and the ratio of the electrical skin contact areas of the electrodes 10, 20, 340.

(11) In this example, the electrical skin contact area of the return electrode 340 is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode 10. This ratio is predetermined and/or controlled to preferably provide r.f. heating proximate, i.e. immediately below, the first r.f. treatment electrode 10 in the first inner region 15 at the first treatment target area 90. If the electrical skin contact area of the return electrode 340 is increased compared to the electrical skin contact area of the first r.f. electrode 10, this will result in increased proximity of the treatment target area 90 to the first r.f. treatment electrode 10.

(12) The inner regions 15, 25 may be located, inter alia, in the epidermis or dermis of the skin. The Figures are very schematic, and in practice, the second inner region 25 may be located only slightly deeper in the skin 60 than the first inner region 15.

(13) The first r.f. treatment electrode 10 is configured and arranged to allow electrical current from the first r.f. generator 18 to pass through an outer surface of the skin and through a first inner region 15 of skin. The second r.f. treatment electrode 20 is configured and arranged to allow electrical current from the second r.f. generator 28 to pass through an outer surface of skin and through a second inner region of skin 25. Both the first r.f. treatment and the second r.f. treatment are provided by operating the electrodes in bipolar mode.

(14) The region which the user wishes to treat may lie on the r.f. current path through the skin, or immediately adjacent to that path. The heat generated in the skin by the r.f. current may spread to adjacent tissue regions. Treatment of multiple regions, both contiguous and non-contiguous, is also possible. The device 300 may thus be configured such that a first treatment target 90, such as the collagen immediately below a wrinkle, is located within the first inner region 15 volume, or that the first inner region 15 is proximate the first treatment target 90. Similarly, the device 300 may be configured such that a second treatment target 95, such as the collagen immediately below a wrinkle, is located within the second inner region 25 volume, or that the second inner region 25 is proximate the second treatment target 95.

(15) When in use for heating the first inner region 15, the first r.f. generator 18 generates an r.f. current which is suitable to heat the skin 60. In other words, the heating occurs in the proximity of the first r.f. treatment electrode 10. The first r.f. treatment electrode 10 allows the r.f. current to pass through an outer surface of skin, and through the first inner region 15 of skin such that a first target area 90 is heated appropriately by the current flowing through the first inner region 15. The current also flows through a further outer surface of the skin to the return electrode 340.

(16) The r.f. current for heating the first inner region 15 and the second inner region 25 may have an AC waveform, with a frequency in the range of 0.3-100 MHz and a power in the range of 1-400 W. A typical frequency used is 0.5-1 MHz, with a power of 25-100 W. The voltage and current for the first and second r.f. energies may differ from each other, and depends on, inter alia, the treatment being performed and the depth of the inner regions 15, 25 below the outer layer of skin.

(17) For example, the first r.f. treatment electrode 10 may be circular in a cross-section through the electrical skin contact area. The electrical skin contact area is proximate and approximately parallel to an outer layer of skin 60 during use. If the first r.f. treatment electrode 10 has a diameter of 0.5 mm in that cross-section, and the distance in the plane of the contact areas of the electrodes 10, 340, is 1 mm, then a typical voltage of the first r.f. may be 15-60V. Treatment duration is typically less than 1 second, in a single pulse or multiple pulses.

(18) The electrical skin contact area of the second r.f. treatment electrode 20 is significantly larger than the electrical skin contact area of the first r.f. treatment electrode 10 this ratio in electrode area is a major factor in determining the ratio between the second volume 25 and the first volume 15. In this example, the electrical skin contact area of the second r.f. treatment electrode 20 is 5 or more times larger than the electrical skin contact area of the first r.f. treatment electrode 10. However, the electrical skin contact area of the second r.f. treatment electrode 20 may be equal to, or significantly smaller than, the electrical skin contact area of the return electrode 340.

(19) The smallest dimension of the electrical skin contact area of the second r.f. treatment electrode 20 is preferably more than 1 mm. The second r.f. treatment will typically take place at a voltage of 50-100V, and the second treatment duration will typically be more than 1 second, using a sustained single pulse, or multiple pulses over a sustained time.

(20) The path of the r.f. current through the first 15 and second 25 inner regions of the skin 60 is determined, inter alia, by the position, geometry and size of the treatment electrodes 10, 20, and the position of electrical contact on the outer layer of the skin. Smaller influences on the path taken may be due to, inter alia, the impedance of the different tissue types through which the r.f. current flows. By providing both the second 20 r.f. treatment electrode and the first r.f. treatment electrode 10 in the same device, the positional relationship between the second inner region 25 and the first inner region 15 may be fixed, or at least made more predictable compared to the separate probes found in the prior art.

(21) Typically, the first r.f. treatment electrode 10, having its largest dimension in a cross-section, comprised in the electrical skin contact area, of 0.1-1 mm, is used for ablative or non-ablative skin rejuvenation. The electrical skin contact area of the second r.f. treatment electrode 20 will be substantially larger. In this example, the corresponding second r.f. treatment electrode 20 may have its largest dimension, comprised in the electrical skin contact area, of 5 mm-10 mm for skin tightening.

(22) The first r.f. treatment electrode 10 may be circular, annular, oval or rectangular in a cross-section comprised in the electrical skin contact area. The geometry of the second r.f. treatment electrode 20 in a cross-section comprised in the electrical skin contact area depends on, inter alia, the preferred mode of movement during use, (for example, whether the device 300 will be stamped in steps onto an outer layer of the skin 60, or continuously glided), the area of skin to be treated, the desired heating volume for the second heating, as well as the desired balance between first and second inner regions of skin tissue. These factors may also depend on the site on the body, and first/second treatment targets 90, 95 being treated.

(23) An example of the electrode geometry as viewed in a cross-section through the contact plane, for the device 300 of FIG. 1, is depicted in FIG. 3A. The first r.f. treatment electrode 10 is round in cross-section and is located between a rectangular second r.f. treatment electrode 20 and a rectangular first return electrode 340, when considered in a plane comprising the electrical skin contact areas of all three electrodes. For example, if, in the plane comprising the skin electrical contact area, the return electrode 340 is located about 10 mm from the centroid of the cross-section of the second r.f. treatment electrode 20, then the voltage range for the second r.f. treatment electrode, when operating to promote tightening in the skin, may be in the range of 50-100V for a duration of more than 1 second.

(24) An array of a plurality of first r.f. treatment electrodes 10 may also be provided for use in a fractional treatment. An example of this electrode geometry, as viewed in a cross-section through the skin contact area, for the device 300 of FIG. 1, is depicted in FIG. 4A. A plurality of first r.f. treatment electrodes 10, round in cross-section, are arranged in a row in a plane comprising the electrical skin contact areas, and are approximately equidistantly arranged between an extended rectangular second r.f. treatment electrode 20 and an extended rectangular first return electrode 340.

(25) FIG. 4B also depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, between an extended rectangular second r.f. treatment electrode 20 and an extended rectangular first return electrode 340. In this example, the r.f. treatment electrodes 10 are arranged in three rows in a plane comprising the electrical skin contact areas, the central row being offset by half the pitch of the first r.f. treatment electrodes 10 in the direction of extension of the rows.

(26) FIG. 4C depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, arranged in a single circular path, approximately equidistantly arranged between a circular second r.f. treatment electrode 20 and an annular first return electrode 340, the first return electrode 340 surrounding both the second r.f. treatment electrode 20 and the first r.f. treatment electrodes 10 in a plane comprising the skin contact area.

(27) FIG. 4D depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, arranged in a single rectangular path, approximately equidistantly arranged between a square second r.f. treatment electrode 20 and a square-frame first return electrode 340, the first return electrode 340 surrounding both the r.f. treatment electrode 20 and the first r.f. treatment electrodes 10 in a plane comprising the skin contact area.

(28) In use, the treatment device 300 may be configured and arranged to influence the degree of coincidence of the first inner region 15 and the second inner region 25 by, inter alia, arranging the second r.f. treatment electrode 20 closer to the first r.f. treatment electrode 10, by changing the cross-sectional geometry of the electrodes 10, 20, 340, by changing the distance between the return electrode 340 and the first r.f. treatment electrode 10, and/or by careful selection of the r.f. energy parameters.

(29) The treatment device 300 may be operated in a first r.f. heating mode, a second r.f. heating mode and a simultaneous treatment mode using a first and a second r.f. heating current. The r.f. generators may be controlled by the controller 30 to provide consistent energy dosages, or variable energy dosages as part of a treatment regime. A combination of sequential or alternating treatments is possible. This may provide gradual tissue contraction. Also pulsing sequences may be optimized to minimize pain or discomfort experienced by the user.

(30) For example, the device 300 may be configured such that the first inner region 15 is completely comprised in the second inner region 25. The first step in the regime may be a suitably long application of second r.f. current to tighten the skin lasting several seconds, followed by a delay of 300 milliseconds or less to allow some thermal dissipation in the second inner skin region, followed by a brief pulse of less than 1 second of first r.f. current to provide skin rejuvenation.

(31) The delay time between the second treatment and the first treatment should not exceed the thermal relaxation time of the dermis (100 ms) and can even be approximately zero. A short delay time allows heated tissue to be treated by the first r.f. current, which may advantageously provide deeper and wider lesions, with a lower first r.f. voltage compared to a conventional device where only a first r.f. current is applied.

(32) The order may be reversed, so that the first r.f. heating occurs first, followed by the second r.f. heating; the first inner region 15 of heated tissue is further heated by the second r.f. current, and may influence the path of the second r.f. current during the second heating.

(33) Further examples of the electrode geometry as viewed in a cross-section through the electrical skin contact areas of the electrodes are depicted in FIGS. 3B to 3D. Typically, the spacing, in a plane comprising the electrical skin contact area, between the edge of the first r.f. treatment electrode 10 and the edge of the return electrode 340 will be in the range of 500 micron to 1 mm.

(34) In FIG. 3B, the first r.f. treatment electrode 10, round in cross-section, is located at the centre of an annular return electrode 340. In FIG. 3C, the first r.f. treatment electrode 10, round in cross-section, is located proximate a v-shaped return electrode 340 along the axis of symmetry of the return electrode 340, and is partially surrounded by said return electrode 340.

(35) Although single electrodes are depicted and described, for some of the embodiments, a plurality of electrodes or arrays of electrodes, either for the first/second treatment and/or the first/second return electrode may alternatively be applied. Such a plurality of electrodes may be operated individually, in groups or all together to provide a high degree of control over the paths of the r.f. current through the skin 60. For example, in FIG. 3D, the first r.f. treatment electrode 10, round in cross-section, is located approximately equidistantly between four return electrodes 340, which are square in cross-section. The four square return electrodes 340 may be electrically interconnected and operated using the same second r.f. energy parameters, or they may each receive individual second r.f. energy parameters. They may also be operated as a group or individually when functioning as the return electrode 340 such flexibility allows a high degree of control over the path of the first r.f. current through the first inner region 15 of skin 60.

(36) FIG. 2 depicts a second embodiment 400 of the treatment device, having the following differences compared to FIG. 1: the second r.f. treatment electrode 20 has been replaced by a further return electrode 420; the treatment device 400 further comprises an electrode function controller 470, electrically connected to the combined electrode 420 and to both the first r.f. generator 18 and the second r.f. generator 28 such that the functions may be switched between them; the further return electrode 420 is configured to operate separately as either a second r.f. treatment electrode, providing bipolar treatment in combination with the return electrode 340, or a return electrode providing bipolar treatment in combination with the first r.f. treatment electrode 10.

(37) Note that, for clarity, the second inner skin region 25 and the skin 60 are not depicted. However, these aspects will be similar to those depicted in FIG. 1.

(38) In other words, during heating of the first inner region 15, the bipolar treatment is provided by the first r.f. treatment electrode 10 and two return electrodesthe return electrode 340 and the further return electrode 420. The first r.f. generator 18 is configured and arranged such that an r.f. current is applied between the first r.f. treatment electrode 10 and both the return electrode 340 and the further return electrode 420 through the first inner region 15.

(39) During heating of the second inner region 25, the bipolar treatment is provided by the second r.f. treatment electrode 420 and the return electrode 340. The second r.f. generator 28 is configured and arranged such that an r.f. current is applied between the second r.f. treatment electrode 420 and the return electrode 340 through the second inner region 25. The electrode function controller 470 is configured and arranged to select the function performed by the further return electrode 420 either as a return electrode or as a second r.f. treatment electrode. In this embodiment, it is not possible to perform both treatments simultaneously. However, alternate and sequential treatments are still possible.

(40) This embodiment 400 increases the area of the first return electrode 340 during the first heating, so that there is a reduced chance of excessive heating below the first return electrode 340, and the heating is concentrated proximate the first r.f. treatment electrode 10.

(41) The further return electrode 420 may be implemented as the same conducting body electrically connected to both the first r.f. generator 18 and the second r.f. generator 28 via the electrode function controller 470. Alternatively, the further return electrode 420 may comprise a second r.f. treatment electrode and a return electrode that are physically distinct, but electrically coupled.

(42) When compared to the treatment device of FIG. 1, the device 400 of FIG. 2 may provide a higher degree of coincidence between the first inner region 15 and the second inner region 25. For some treatments, the device 400 may be configured and arranged such as to cause the first inner region 15 to be completely comprised in the second inner region 25.

(43) As shown in FIG. 1, the electrode geometry in a cross-section of the electrical skin contact area may be as depicted in FIG. 3A. The first r.f. treatment electrode 10 is round in cross-section and located, in a plane comprising the electrical skin contact areas of the electrodes, between the rectangular further return electrode 420 and the rectangular return electrode 340.

(44) A further example of the electrode geometry for the device 400 is depicted in FIG. 4A. A plurality of first r.f. treatment electrodes 10, round in cross-section, are arranged in a row in a plane comprising the skin contact areas, approximately equidistantly arranged between a further return electrode 420 and the return electrode 340.

(45) FIG. 4B also depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, arranged between a further return electrode 420 and the return electrode 340. In this example, the r.f. treatment electrodes are arranged in three rows in a plane comprising the skin contact area, the central row being offset by half the pitch of the first r.f. treatment electrodes 10 in the direction of extension of the rows.

(46) FIG. 4C depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, arranged in a single circular path, approximately equidistantly between a circular further return electrode 420, and an annular return electrode 340, the annular return electrode 340 surrounding, in a plane comprising the electrical skin contact areas, both the further return electrode 420 and the first r.f. treatment electrodes 10.

(47) FIG. 4D depicts a plurality of first r.f. treatment electrodes 10, round in cross-section, arranged in a single rectangular path, approximately equidistantly between a square further return electrode 420 and a square-frame return electrode 340, the return electrode 340 surrounding, in a plane comprising the electrical skin contact areas, both the further return electrode 420 and the first r.f. treatment electrodes 10.

(48) It may be advantageous if the treatment device further comprises an impedance measurement circuit, connected to one of the electrodes, and configured and arranged to measure, in use, the impedance of the radio-frequency current path through the inner region of skin. A lower impedance would increase the electrical transmission of the radio-frequency current through the skin. If the impedance measurement circuit is connected to the r.f. generator, it may be configured and arranged to select at least one parameter of the r.f. treatment current in accordance with the impedance measured. Suitable parameters may be: the duration that the current is applied, the voltage, the frequency, pulse duration and duty cycle, and the maximum current to be applied.

(49) Similarly, skin contact can be detected by using an appropriate sensor, for example a capacitance sensor, or by measuring the skin impedance with a small measuring (pre)pulse of about 20V.

(50) It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments.

(51) In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb comprise and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article a or an preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer.

(52) The word module should not be interpreted to mean that the functionality and hardware are distinguishable in the device. It is used to indicate a functionality that the device comprises, and, in practice, different modules may use partly the same or entirely the same hardware and optical components.

(53) In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. 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.

OVERVIEW OF REFERENCE NUMBERS

(54) 10 first r.f: treatment electrode 15 first inner region of the skin where r.f. treatment current may flow 18 first r.f: generator 20 second r.f. treatment electrode 25 second inner region of the skin where r.f. treatment current may flow 28 second r.f. generator 30 controller 60 Skin 90 first treatment target (in first inner region of the skin) 95 second treatment target (in second inner region of the skin) 300 Bipolar skin treatment device (1.sup.st embodiment) 340 return electrode 400 Bipolar skin treatment device (2.sup.nd embodiment) 420 further return electrodefirst return and second treatment 470 electrode function controller