WO2014141014A1

WO2014141014A1 - Apparatus and method for skin treatment with visible and infrared light

Info

Publication number: WO2014141014A1
Application number: PCT/IB2014/059510
Authority: WO
Inventors: Albert AMAT I GENIS
Original assignee: GIBERT GINJAUME, Francisco Javier
Priority date: 2013-03-11
Filing date: 2014-03-07
Publication date: 2014-09-18

Abstract

According to one of the aspects of the present invention, there are described an apparatus and a method to treat the skin, to be applied to face, body or both, based on the utilization of polychromatic light produced by the association of a plurality of substantially monochromatic light sources, sources that comprise LED. Intensity power supplies designed to maximize the lifetime of the light sources and allow both intensity regulation and wavelength combination control. Emitted light by the apparatus necessarily contains violet-blue emission, in a spectrum between 400 and 450nm; the emitted light by the apparatus also contains either red light, of a wavelength between 605 and 655nm; or infrared emission, of a spectrum between 785 and 835nm; or both red and infrared emission of the characteristics described above.

Description

PATENT OF INVENTION

APPARATUS AND METHOD FOR SKIN TREATMENT WITH VISIBLE AND INFRARED LIGHT

The present invention describes an apparatus and a method for treating the skin, suitable to be applied to face, body or both, based on the utilization of polychromatic light produced by an association of a plurality of light sources which are substantially monochromatic, light sources which include Light Emitting Diodes (LED); the light sources are controlled by means of a plurality of power supply elements controlling current, in order to maximize the lifetime of the apparatus, allowing current intensity regulation and the emission of specific wavelength combinations to produce the maximum treatment efficacy.

SECTOR OF THE TECHNIQUE

The apparatus and method described by this invention are destined to the aesthetic medicine, dermatologic medicine, aesthetic and wellness sectors, which comprise fitness centres, saunas, aesthetic salons and coiffure salons.

STATE OF THE ART AND BACKGROUND TO THE

INVENTION

It is known since many years that the utilization of devices which emit ultraviolet (UV) light induces melanogenesis on the skin, which consists on the production of melanin by the melanocyte cells, protecting skin from the radiation which induces the tanning response; macroscopically, the process produces darkening of the skin which has been exposed to the radiation. UV light emitted by those devices is mainly found in the UVA range, with an spectral range from 320 to 399nm, with a contribution of UVB emission in a lower percent of total energy, of wavelengths from 280 to 319nm. Light sources used by those devices are mainly fluorescent tubes. From this situation, an evolution is needed mainly on two fields, which are:

1) Biological, since there is a growing evidence of the relation between UV exposure and cutaneous cancer and skin aging. This situation produces that many countries are issuing strict regulations for the use of UV devices, and also affects the way that final users perceive the technique, since they consider it a risky treatment. As a result, a dramatic decrease of the use of this treatment has been observed, despite of the psychological benefits that melanogenesis produce, which are related to brain production of endogen opiate, and of the charming look of tanned skin.

2) Technical, where considerations are related to lifetime of light sources and the safe filtering they need: it has been demonstrated that fluorescent tubes, after 250 hours of usage, decrease their emitted power to the 75% of the initial power. In addition, the safe filters that are constructively added to the light tubes in order to block the more pernicious part of the spectrum that is emitted by the sources, are progressively deteriorated by usage. As a result, a maintenance service of UV devices is required to periodically measure efficacy and safe parameters, eventually replacing damaged tubes, which increases the cost of the treatment.

As an attempt to overcome these issues, new approaches to artificial light tanning have been proposed. In US2004232359 "Skin tanning and light therapy incorporating light emitting diodes", in KR20120095528 "Tanning apparatus using UV-LED and polarized film" and in GB2420078 "Tanning quilt incorporating light emitting diodes" it is proposed the use of UV LED, which emission spectra is known to induce melanogenesis, in order to narrow the UV spectra emission, thus making the light sources substantially monochromatic.

In US2010179622 "Skin treatment device, lamp and use" it is proposed the combination of wavelengths, adding to UV light energy emitting in the visible spectrum, which may have eventually tanning effects, in order to reduce the total amount of UV light reaching the skin. At this point it is important to mention that a number of publications, comprising Parrish JA, Jaenicke KF, Anderson RR (1982) "Erythema and melanogenesis action spectra of normal human skin" Photochem. Photobiol. 36, 187-191; Mahmoud BH, Hexsel CL, Hamzavi IH, Lim HW (2008) "Effects of visible light on the skin" Photochem Photobiol. Mar-Apr;84(2):450-62; and Mahmoud BH, et al. (2010) "Impact of long- wavelength UVA and visible light on melanocompetent skin" J Invest Dermatol, 130(8):2092-7, show that light in the visible spectrum induces melanogenesis. It is obvious that this opens new therapeutic possibilities, despite of a number of limitations: in the first publication, the authors do not observe effects produced by wavelengths higher than 405nm, and in the 2008 and 2010 publications, the authors use a light source of too broad spectral range (380- 800nm) to discriminate which part of the spectrum is responsible for the observed effects or whether some other light contained in the emission contributes in some way to skin tanning. Roughly, the effect of a source of the latter characteristics could be compared to exposing the skin to solar radiation after applying to its surface UVA and UVB filters. Finally, in EP2386329A1 "Apparatus for the skin treatment with visible Light" it is proposed skin tanning by means of 405nm LED emission, treatment that follows from the state of the art information. In this case it is also important to mention that 405nm peak emission for LED sources produces that a very significant percent of total energy emission falls under UVA radiation, that is, 30-40% of the emission will be under 400nm.

An important feature regarding tanning following artificial light exposure is the duration of the effects in the skin. Scientific literature mentions that UVA exposure does not produce new melanin synthesis but darkening of melanin already existing in the skin by an oxidation mechanism, which results on a grayish skin color, which vanishes after hours or very few days. Because of this effect, UV tanning devices also include some UVB radiation in their spectrum, since this radiation induces melanin synthesis and the effects on the skin last longer. This information is stated in the paper Miyamura Y et al., The deceptive nature of UVA tanning versus the modest protective effects of UVB tanning on human skin, Pigment Cell Melanoma Res 2011 Feb;24(l):136-47. Despite very few information can be found, it would be expected that the tanning duration effects of 405nm light would be closer to those of UVA, which spectral range finishes at 399nm, because of contiguity of spectra. Following this hypothesis, it should be expected that light at 405nm would induce short lasting results, being this characteristic an important issue for customers of tanning treatments. But it is also possible to find publications that show results that contradict those of the former paper, since Mahmoud BH, et al. (2010) "Impact of long-wavelength UVA and visible light on melanocompetent skin" J Invest Dermatol, 130(8):2092-7 state that tanning effects of visible light on skin last for longer than those of UVA, but, as noted, the light source used for this research include some IR light that could distort the observed effects. The contradictions noted here show that the mechanism of UVA and visible light effects on skin is not yet fully understood.

The present situation can be stated as follows:

Artificial light tanning following UVA and UVB exposure is not safe because of the demonstrated side effects, i. e. carcinogenesis and skin aging.

Despite skin exposure to substantially monochromatic visible light may induce some degree of tanning, the constructive method of LED sources will produce that emitters with a peak too close to 400nm will contain significant energy in the UVA range, i.e. lower than 400nm, since the spectral range of these kind of source is tenths of nanometres broad.

Finally, it would be possible that safer light sources, i. e. not in the UV range but in the visible spectra, would produce short lasting tanning effects.

It is well known that skin effects following substantially monochromatic light irradiation, which may be produced using LED, depending on which biological chromophores it interacts, would produce a biological response that should be able to be quantitatively and/or qualitatively characterized. It can be also easily understood that a synergy of effects that would quantitatively and/or qualitatively increase the desired biological effects, if the light that is used falls in the range of wavelengths that is safe for the body, should be preferred and understood as a competitive advantage.

Finally, regarding technical issues of safety and lifetime of light sources, when fluorescent tubes are used, the utilization of safer light sources, which LED are an example but not the only ones, since the key characteristic of preferred light sources should be related to spectral broadness and radiant power, not to their nature or constructive method.

For all these reasons, to produce an emission in a safe spectral and efficient range, and to obtain a synergy of results by means of combining different substantially monochromatic light sources, having as well as a key objective the safety of light sources that are used to expose human skin, the inventors propose the present invention as an apparatus and method of treating skin to induce its tanning.

DESCRIPTION OF THE INVENTION

This invention is a very significant innovation in the fields of aesthetics, aesthetic medicine and general dermatology.

EXPLICATION OF THE INVENTION

1) Scientific bases of the invention

The inventors did conduct research to evaluate the effects of exposing the skin to light emission using a definite source that is described as part of the invention, and as a result a method of treatment has been developed.

The wavelengths whose effects were studied are those comprised between 400 and 450nm, with a maximum in between 420 and 425nm; between 605 and 655nm, with a maximum at 630nm; and between 785 and 835nm, with a maximum at 810nm. The wavelengths here mentioned correspond respectively to violet-blue, red and infrared emission spectra. The present invention proposes in all cases the combination of substantially monochromatic light to obtain the desired result. For the experimental prototype, there were used Light Emitting Diodes (LED), although other light sources being substantially monochromatic would produce the same results, since the latter are caused by a number of photons of a defined wavelength narrow range, emitted during a defined time (power of the light source). The nature of the light sources, granted the required just mentioned emission characteristics, is not a part of the invention. However, it is a substantial part of the invention the method to combine certain wavelengths and the apparatus needed to fulfil the method requirements, mentioning that one of the possible ways to construct such an apparatus uses LED as light sources.

In the experiment that is the scientific basis of the invention, skin exposition to light has been applied to healthy human volunteers on a number of body parts.

The polychromatic light source has been specially designed and constructed for the experiment, since it was not found in the market.

The effects of the light exposition were evaluated by a scientifically accepted method, described in Taylor, S., Westerhof, W., Im, S., & Lim, J. (2006). Noninvasive techniques for the evaluation of skin color. Journal of the American Academy of Dermatology, 54(5), S282-S290, consisting on measuring the reflectance of the skin by an optical fibre and a fluorimeter (FluoroMax, Horiba Scientific, Edison NJ USA) by a synchronic experiment consisting on irradiating the skin at a given wavelength and measuring the reflected or scattered light of the same wavelength. The measurement is proportional to the amount of melalin which is in the skin, since: (i) the experiment has been performed on a wavelength range between 350 and 680nm, spectrum where the melanin shows strong absorption coefficient; (ii) the darker is the skin, the less light would be reflected or scattered, since larger energy will be absorbed by skin melanin; (iii) consequently, the experimental measurement value would be inversely proportional to the skin darkness. Experiments showed highly reproducible allowing the inventors validate them as a valid method for evaluating their invention.

Skin exposition to the light source described by this invention, at different body parts, lasted 12 minutes on successive or alternated days, for a total number of sessions. The maxima of the light were at 420-425nm, 630 and 810nm, exposing the skin both to monochromatic light and to a combination of monochromatic energy: 420-425 plus 630nm; 420-425 plus 810nm; and 630 plus 810nm. Non- exposed skin was used as a control. Consequently, there were obtained 7 experimental groups: (a) control, non-irradiated skin; (b) irradiation at 420- 425nm; (c) irradiation at 630nm; (d) irradiation at 810nm; (e) irradiation at 420- 425 plus 630nm; (f) irradiation at 420-425 plus 810nm; (g) irradiation at 630 plus 810nm. The experimental results showed that skin exposed to light as per groups (c), (d) and (g), containing no emission at 420-425nm, did not produce any change of skin colour; but all groups containing light emission at 420-425nm, e.g. groups (b), (e), and (f), darkened the skin. Experimental results are presented as follows: skin measurements of group (1), control, it is measured the value for each of the studied wavelengths (350nm to 680nm, lnm steps). These individual values are considered as 100% for each wavelength. The difference with experimental groups 2 to 7 is expressed in percent variation from control to experimental groups. Finally, the percents of every single wavelength, 380nm to 680nm, are averaged for each group, thus obtaining a final value for groups 2 to 7 that expresses the change (increase) of color, if any, compared to group 1, in a percent value.

Experimental results showed unequivocally that skin color was increased after skin exposure to 420-425nm light only by 27.1% compared to control, which could, but not necessarily, be somehow predicted after the state of the art analysis. However, it is substantially new the fact that combination of violet-blue light with either red or infrared light increased not only the color when compared to non- irradiated skin but also when compared with skin irradiated only at 420-425nm. 420-425nm plus 630nm light showed a color increase of 31.5% compared to control skin, and the result for the combination of 420-425nm and 810nm light was of a 29.8% percent. These results are plotted in graph 1.

% increase of skin color

420-425nm 420-425&635nm 420-425&830nm

Graph 1. Experimental results of skin irradiation with the apparatus and method described by the present invention, were it is observed the percent increase of color when compared to non-irradiated skin for 420-425nm light only (27.1%), 420-425nm plus 630nm light (31.5%), and 420.425nm plus 810nm light (29.8%).

Since for all irradiated groups radiant exposition of light energy was the same in terms of total Joules/cm², both when single wavelength and when combined wavelengths were used, it follows that differences on skin color are not due to amount of energy that was delivered but to the quality of that energy. Since irradiation with either 630nm, 810 or 630nm plus 810nm light does not increase skin color, the effects must be produced by a -for this moment- unknown kind of interaction of polychromatic light necessarily containing 420-425nm energy with skin chromophores that trigger some collateral biochemical reaction or that increases efficiency of the reaction that 420-425nm light produces on melanogenesis. In any case, this new mechanism is still unknown for the inventors, but they want to underscore that it has been made evident as a result of the construction of an apparatus that is able to deliver a combination of substantially monochromatic wavelengths and of the design of a concrete method for treating the skin, both -apparatus and method- being the object of the present invention. In all cases, skin color increase last for at least 15 days, with a decrease of only 10% after 10 days of the last session. Color progressively faded after two weeks after last session.

The apparatus that is the object of the present invention could potentially be used for treatments other than skin tanning. As non-limiting examples, there is the possibility to use blue light at 420nm as an anti-bacterial agent for acne treatment, based on the paper Dai T. et al., Blue light for infectious diseases: Propionibacterium acnes, Helicobacter pylori, and beyond?, Drug Resist Updat 2012 Aug;15(4):223-36. The apparatus may be also used to repair acne lesions, since 630nm light stimulates synthesis of fibroblasts and activation of cellular biomolecules, as can be observed in the paper Volpato LE et al. Viability of fibroblasts cultured under nutritional stress irradiated with red laser, infrared laser, and red light-emitting Diode, J Biomed Opt2011 Jul;16(7):075004 and Amat A et al. Modification of the intrinsic fluorescence and the biochemical behavior of ATP after irradiation with visible and near- infrared laser light. J Photochem Photbiol B 2005 Oct 3;81(l):26-32.

Another suitable treatment that could be performed by the apparatus that is the object of the present invention is an also novel skin protection double mechanism: to the tanning affects that would be produced by the polychromatic light association described above, which protects from on the skin against natural or artificial UV radiation and, as a consequence, prevents the photoinduced skin aging, there is added the antiaging effect that 630nm light possesses -and at a lesser extent, that of 810nm energy- and the cancer-prevention effects that violet- blue light possesses. The above photobiological effects are describe in Tian YS, Kim NH, Lee AY. Antiphotoaging effects of light-emitting diode irradiation on narrow-band ultraviolet B-exposed cultured human skin cells. Dermatol Surg. 2012 Oct;38(10):1695-703; Ohara, M., Kawashima, Y., Katoh, O., & Watanabe, H. (2002). Blue light inhibits the growth of B16 melanoma cells. Cancer Science, 93(5), 551-558; and Sparsa A. Et al. Blue Light is Phototoxic for B16F10 Murine Melanoma and Bovine Endothelial Cell Lines by Direct Cytocidal Effect, Anticancer Research January 2010 vol. 30 no. 1 143-147. The inventors consider the latter a very interesting potential treatment, which would be totally produced by means of safe visible energy. This treatment could is able to be performed by the apparatus that is the object of the present invention, without substantial modifications of its design.

The examples of treatments described above are not limiting for the present invention, and the inventors think that further research would allow developing novel therapeutic possibilities for the apparatus.

2) Technical basis of the invention

The key characteristic of the present invention is the application of polychromatic light, resulting of combining substantially monochromatic light -like that produced by LED- to skin, facial, body or both, to obtain certain biological effects, e.g. the melanogenesis, resulting on safe (since no UV is present) and consistent skin tanning. To achieve the desired objective, it is necessary to define the required combination of wavelengths in a certain way, thus defining the desired combination of monochromatic light in terms of irradiation surface containing the different monochromatic sources; in terms of percent of energy of each monochromatic source; or both. In the treatment described by this invention the percent of 420-425nn light will be always greater than 50%, preferably between 70 and 90% of total energy emitted. The remaining percent will correspond to red light, to infrared light or to both. This relation between emitted light wavelengths could be illustrated by different constructive models, from which the inventors will describe two of them, which would be not limiting for further developments of the apparatus described by the present patent. In both embodiments that will be described below, or in any other different realization that could be developed for the present invention, a full therapeutic device, treating face, body or both, will have to comprise a number of minimum units of treatment, defined as the units that emit energy containing all the characteristics of polychromatic light and power required for the treatment, which will be physically and electronically connected, thus shaping the total treatment surface of light emission of the final device.

Prototype of this invention used LED as light sources, but other sources sharing a number of characteristics with LED could be as well used. But even using LED as light sources, the resulting apparatus would be much more safe that any apparatus using fluorescence tubes, even if they could be constructed to emit monochromatic light: (i) efficiency of LED is much greater than that of fluorescent tubes; (ii) resistance to aging of LED is orders of magnitude greater than that of fluorescence tubes (LED emits by 90% of initial power after 20000hours, while tubes fall at 75% of initial power after only 250hours); (iii) filtering of undesired wavelengths of tubes age as well over time.

The present invention describes two different areas that need to be combined in order to obtain the desired biological results. The first part is the apparatus, which is the technological basis to permit the application of the treatment, and that is described in this invention by concrete constructing possibilities. The second part is the method by which the apparatus has to be used. The method consists on: (i) combining in a certain percent light of violet-blue spectrum with light of red, infrared or both red and infrared spectra; (ii) and applying to the skin the energy in a definite fashion, that means, according to a certain number of sessions, a session interval, a session duration, a distance from apparatus to the skin, the concomitant possible application of cosmetic or pharmaceutical products before, after, and/or during sessions. The characteristics of (i) have been already mentioned. As an example for (ii), it is proposed a combination of parameters that showed experimental success on skin tanning: five sessions, applied daily, of 12minutes of duration, being the apparatus at 20cm of the skin, and applying a moisturing lotion to the skin after every session.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1. Electric circuit that was used to build the prototype of the present invention. This circuit is only an example of the many that can be used to drive light sources, and it is no limiting for the construction of devices that will follow from the present invention. The circuit contains, among other elements, a switched-mode power supply of 48V, a MOSFET transistor (Ql) and LED (D1-D5).

FIG. 2A/2B. Non-limiting example of a bichromatic light treatment unit. A: package (1) of 6 monochromatic chips, 5 emitting at 425nm (2) and 1 emitting at 630nm (3), connected in series, with a common anode and cathode (4). B: side view of (1), where it is observed the frontal lens element (5) to concentrate and homogenize the different wavelengths that would be emitted by (1).

FIG. 3. Non-limiting example of a treatment panel (6) that conforms a treatment unit, consisting on 6 units emitting monochromatic energy -these units formed by either chips (2) or (3); (7) shows a zoom on of one of these units. Five of these composite units may emit light at 425nm (8), and one of the units would emit at 630nm (9). In this example, units (8) and (9) are connected in series, with common anode and cathode for the entire treatment unit. It is possible as well an independent connection for packages depending on their emission wavelength, in order to electronically precisely control the percent of wavelength combination -in a similar fashion that can be made for monochromatic emitters (2, 3). As a non- limiting example, panel (6) could have a surface of 40cm².

FIG. 4. Non-limiting example of a facial treatment apparatus (11) based on the apparatus that is the object of the present invention, consisting of multiple bichromatic elements (6), each of them consisting, as a non-limiting example, of five packages emitting at 425nm (8) [each of them formed by chips of the type (2)], and one package emitting at 630nm (9) [each of them consisting of chips of the type (3)] . These polychromatic elements will have to be constructed according to the principle of therapeutic unit of minimum surface, in order to produce energy in a homogeneous and uniform fashion when reaching the skin, allowing the synergic effect described above that is one of the objects of the present invention.

FIG. 5. Non-limiting example of facial treatment that can be performed by a treatment panel (11) as a concrete embodiment of the apparatus that is the object of the present invention, showing how the skin surface is placed in front of the polychromatic emitter, and the ocular protection necessary to avoid the undesired effects of light energy.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The main characteristic of the present invention is to apply polychromatic light to the skin, face, body or both, in order to produce a very concrete biological response, i. e. stimulation of melanogenesis, resulting on safe and effective skin tanning. To achieve this objective, it is necessary to combine substantially monochromatic wavelengths in the way that is described in the method that is the object of the present invention. To define this method, it is required to define its parameters in terms of surface of irradiation and percent of wavelength of each monochromatic light to produce polychromatic emission. In the method here described, the percent of 420-425nm light must be always higher than 50% of total delivered light, and its percent would preferably be from 70 to 90% of total light emitted by the device resulting from the present invention. This relation between emitted light wavelengths could be illustrated by different constructive models, from which the inventors will describe two of them, which would be not limiting for further developments of the apparatus described by the present patent. In both embodiments that will be described below, or in any other different realization that could be developed for the present invention, a full therapeutic device, treating face, body or both, will have to comprise a number of minimum units of treatment, which will be physically and electronically connected, thus shaping the total treatment surface of light emission of the final device.

The first step to describe an embodiment is the construction of the power circuit to control the LED. The circuit described below is only an example of the many that can be used to drive light sources, and it is no limiting for the construction of devices that will follow from the present invention. The circuit in fig. 1 contains a switched-mode power supply of 48V, where a MOSFET transistor (Ql) periodically switches between states. In the first step the transistor is closed, and current flows through LED (D1-D5) and the coil. Current progressively increases in the coil and in the LED, until its value is higher than the maximum value that has been programmed for the system. At this moment, transistor Ql opens and by means of the recirculation diode (D6), the coil keeps delivering current to the LED and the intensity of current starts to decrease. When the intensity is lower that the lowest programmed value, the controller closes again the transistor (Ql) and the intensity that circulates through the LED starts to increase again. Commuted power supplies of the type that are used here show significant advantages compared to other power supplies like linear ones. In this case, the key advantage would be the efficiency of the power supply when high power circuit -as it is the case, since final devices would be of a power of 8-10 KW or even higher- are used. Efficiency of switched power supplies could be up to 90%, and linear ones have a maximum efficiency of 50-60%.

Once constructed the power and control circuit, it will be described the mode of achieve the required polychromatic light emission. The first and preferred mode of realization would be to physically and electronically bond in a same package a variable number of monochromatic emitter LED chips according to the percent of energy of each wavelength that would be required over the total delivered energy.

As an example, it is shown in Fig. 2 A a package (1) that contains 5 monochromatic chips emitting at 425nm (2), and one monochromatic chip emitting at 630nm (3), thus resulting on an approximated combination of energies of 83% for 425nm energy and 17% for 630nm, the latter in the case that monochromatic chips work at the same voltage, have the same efficiency and are connected in series, as the example shows, with a common anode and cathode (4) for the entire constructive unit. A way to vary the percent of monochromatic energy over the total delivered energy is by splitting the electrical connections and constructing different anode-cathode for different wavelength chips, and subsequently varying the current for different wavelengths.

The package (1) includes a frontal lens element (5) in order to concentrate and homogenize the energy delivered to the skin, thus increasing the efficacy of the treatment and lowering the constructive costs of the device, since less amount of energy would be lost on the way to the skin when such an element is added to the design. (Fig. 2B) The concrete embodiment of the present invention described above is a very significant competitive advantage compared to any other possible realization of the apparatus described by the present invention using LED as light sources, since an emitting surface lesser than 2cm², preferably consisting of a surface in between 0.1 and 0.5 cm², would contain the specific and necessary wavelengths to allow a successful treatment, energy that would be homogenized and concentrated by means of the lens elements added to the frontal part of the package, thus hitting the surface of skin uniformly. In the above describe mode of realization, the ratio polychromatic treatment surface/ irradiated cutaneous surface would be the lesser constructively possible, to allow maximum homogeneity when treating the skin. A plurality of the described packages may be mounted on specially designed panels, which will be put together to conform the total surface of treatment for a final device, for face, body or both.

Since the skin that would be treated will have to be at a certain distance of the device that is the object of the present invention, distance that would have to be less than lm, preferably in between 15 and 30cm, it would be possible to use therapeutic units that could be larger than the package (1), since that distance would allow the different wavelengths emitted by the device to combine and, at the time they will reach the skin, the energy will be homogenized to produce a successful treatment. It is for this reason that the inventors propose an alternative embodiment, not constructively-limiting to other possibilities, to deliver the energy to the skin, where combination of wavelengths does not occur in the package but in larger units. This second embodiment consists on assembling, in series or by independent current controllers for different wavelengths, a number of packages of monochromatic light (7, 8, 9) fixed on a treatment panel (6) as shown in fig. 3. To assure a successful treatment, the treatment units (6), where different monochromatic units are assembled and connected, need to have a surface size not exceeding of a concrete value, i. e. not larger than 50cm², and preferably in between 25 and 40cm². Again, a number of these units have to be assembled physically and electrically to conform an apparatus to treat face, body or both.

Figs. 4 shows a final treatment device (11), constructed by assembling a number of panels/treatment units (6), and fig. 5 shows how facial treatment may be performed in a non-limiting example of a device to treat the face, where person wears ocular protection for a safe treatment.

The embodiments shown above, or similar ones that could be designed to follow the method that is the object of the present invention, are essential for the treatment success, since otherwise it would be impossible to deliver to the skin an enough amount of energy, polychromatic of a concrete wavelength combination, and homogenized when energy reaches the skin, delivering the treatment by means of a minimum surface therapeutic unit, in order to obtain the synergy that specific wavelength combination produces. The latter is a very significant competitive advantage when comparing to devices that would eventually emit light of a single wavelength, eventually in the violet-blue part of the electromagnetic spectrum, because the treatment that is object of the present invention produces larger effects in terms of skin tanning; and also compared to devices that would eventually emit energy at different wavelengths in which the effects of their wavelengths are just the addition of the effects of the single wavelengths but not a result of a synergy produced by a concrete wavelength combination.

Claims

Apparatus for treating the skin with visible and infrared light, to be applied to face, body or both, consisting on a plurality of light sources connected to power supply, characterized in that:

a. The light sources that are part of the apparatus are sources of substantially monochromatic wavelength spectrum emission, i.e. with a sufficient narrow emission spectrum, and enough power to reach the desired therapeutic effects, being combined in the same apparatus light sources of different substantially monochromatic light, to obtain a resulting emission of polychromatic light; the light sources that constitute the apparatus do necessarily contain elements that produce energy in a spectrum in between 400 and 450nm; in addition to the latter sources, which do emit in the violet- blue spectrum, the apparatus contains either light sources emitting in the red section of the spectrum, of wavelengths in between 605 and 655nm; either light sources emitting in the infrared section of the spectrum, of wavelengths in between 785 and 835nm; either sources in the red and in the infrared section of the spectrum, being these red and infrared sources of the characteristics above mentioned.

b. The power supply contains electronic switches and current intensity control to maximize efficiency and lifetime of the light sources.

Method for treating the skin by means of the application to its surface of visible or visible and infrared electromagnetic energy, to be applied to face, body or both, characterized in that:

a. The light to be applied to the skin, consisting on polychromatic light resulting from the simultaneous emission of a plurality of substantially monochromatic light sources, this polychromatic light being emitted by the apparatus of claim 1. This emission necessarily contains violet-blue energy in a range between 400 and 450nm, and additionally contains one or both of the following emission: (i) red emission of a spectrum between 605 and 655nm; (ii) infrared emission of a spectrum between 785 and 835nm.

3. Apparatus according to claim 1, characterized in that the light sources that it contains are grouped to constitute treatment modules, which may be independently controlled.

4. Apparatus according to claims 1 and 3, which use Light Emitting Diodes (LED) as light sources.

5. Apparatus according to claims 1 and 3, in order to implement the method according to claim 2, characterized in that the substantially monochromatic light sources that it contains, which are grouped to form minimum surface units to emit polychromatic emission, being these units defined as a surface of an area that is necessarily lesser than 100cm², containing the plurality of light sources that are required to allow a successful treatment, in order to assure a sufficient degree of homogeneity and uniformity of the wavelength combination. The concrete characteristics of these therapeutic units depend on the concrete embodiments of the apparatus and may coincide with the independent modules of the electronic control of the apparatus.

6. Apparatus according to claims 1, 3 and 5, characterized in that having a total light- emitting surface that is suitable to treat face, body or both body and face, thus comprising a number of minimum treatment units according to claim 5, of the type those units may be. These units are physically and electronically assembled to conform the total treatment surface of the apparatus.

7. Apparatus according to claim 5, which comprises different embodiments in order to obtain a uniform and homogeneous polychromatic light emission to reach the skin, which follows from the concept of minimum treatment surfaces. A first embodiment resulting from the first preferred technical design of the apparatus uses in a single package (1) substantially monochromatic emitter chips of different wavelengths (2, 3), which may be connected either in series, with a common anode and cathode (4), either the chips of the same wavelength are connected together, the latter to more accurately control the intensity and percent of each emission type. The surface of these grouped-chips units would be lesser than 2cm², preferably in between 0,1 and 0,5cm².

8. Apparatus according to claim 7, comprising the mounting in the frontal part of the package (1), from where energy is emitted to reach the skin, of an optical element (5) to homogenize and concentrate the light energy.

9. Apparatus according to claim 5, which comprises a second possible embodiment consisting on the utilization of a number of packages (8, 9), all of them emitting at only one substantially monochromatic energy since they include only monochromatic chips (2, 3). The packages above mentioned (8, 9) are to be combined in a surface (6), where packages are electronically controlled, in order to obtain a specific combination of substantially monochromatic energy, to produce polychromatic emission. The monochromatic packages (8, 9) may be either connected in series with a common anode and cathode (10), either the packages of the same wavelength are connected together, thus controlling independently the different wavelengths to a more accurate control of both the intensity and the percent of monochromatic components of the total polychromatic emission. In the embodiment just described, the minimum treatment units consist on a surface (6) having and area lesser than 100cm², containing the light sources. The latter surface would preferably be of an area in between 25 and 50cm², and more preferably of an area in between 30 and 40cm².

10. Apparatus according to claim 9, which comprises the mounting in the frontal part of the surface of the minimum treatment unit, that that emits light and is directed towards the skin, a single or a plurality of optical elements for homogenizing and concentrating the light energy.

11. Method according to claim 2, executed by the apparatus according to claims 1, 3, 5, 6, 7, 8, 9 and 10, characterized in that always requiring of a light emission to treat the skin of contemporary different substantially monochromatic wavelengths: in this combined emission the percent of energy of the violet-blue section of the spectrum, of wavelengths in between 400 and 450nm, contained by the total light emission is always greater than 50%, in terms of total emitted power, and preferably the percent of violet-blue light is in between 70 and 95% of total emitted energy. The difference of the energy emitted of violet-blue emission to 100% of total power will correspond either to red light, of wavelengths between 605 and 655nm; or to infrared light, of wavelengths between 785 and 835nm; or to a combination of red and infrared emission, being the red and infrared energy of the characteristics mentioned above.

12. Apparatus according to claims 1, 3, 5, 6, 7, 8, 9 and 10, characterized in that the emission of electromagnetic energy of the violet-blue spectrum, preferably of a spectrum between 410 and 440nm; of the red spectrum, preferably between 620 and 645nm; and of the infrared spectrum, preferably between 795 and 825nm.

13. Method according to claims 2 and 11, characterized in that the application of electromagnetic energy of the violet-blue spectrum, preferably of a spectrum between 410 and 440nm; of the red spectrum, preferably between 620 and 645nm; and of the infrared spectrum, preferably between 795 and 825nm.

14. Apparatus according to claims 1, 3, 5, 6, 7, 8, 9, 10 and 12, characterized in that the emission of electromagnetic energy of a spectral maxima of 420- 425nm, 630nm and 810nm.

15. Method according to claims 1, 11 and 13, characterized in that the application of electromagnetic energy of a spectral maxima of 420-425nm, 630nm and 810nm.

16. Method to produce skin tanning by means of electromagnetic energy according to claims 2, 11, 13 and 15, characterized in that modalities of application to the skin, which comprise treatment sessions in which the skin to be treated will be placed at a distance from the apparatus lesser than lm, preferably between 10 and 50cm, and more preferably between 15 and 30cm. The treatment sessions could be performed daily, on alternate days, or with an interval greater than one day between them. The duration of the sessions will be lesser than 30minutes, preferably between 10 and 20minutes. Before the session, during the session or once the session is over, cosmetic or pharmaceutical products could be applied to the skin, to produce beneficial effects on it, effects that comprise skin nutrition, hydration and regeneration.

17. Apparatus for skin tanning according to claims 1 and 3, characterized in that one of the control elements is a MOSFET transistor (Ql).

18. Apparatus for skin tanning according to claim 17, characterized in that the power source contains at least one recirculating diode (D6).