Light irradiation unit for diagnosing and treating skin problems

0001The present invention relates to a light irradiation unit for diagnosing and treating skin problems and for hair removal treatments.

0002By subjecting the skin to light beams of various intensities and various duration, it is possible to obtain from said skin information regarding its state and characteristics, which can be used for diagnostic purposes.

0003Further, different combinations of light irradiation of the skin can facilitate the reduction of some kinds of dermatological disorder and improve their aesthetic appearance. For example, with treatments of this kind it is possible to eliminate or reduce the number of fine capillary vessels (telangiectasias) and to provide permanent or semipermanent hair removal on the treated surfaces.

0004Devices are commercially available which are provided with a lamp commonly used for flashing luminous indicators (for example sirens with flashing lamp for flying-squad vehicles), which has a higher power because it has not only a visual effect but also a heat generation effect.

0005The lamp is fitted inside a mirror-finished parabolic reflector, which causes the light to converge toward a specific point on the skin. All this is inserted within a handpiece provided with a button for activating the emission of light radiation.

0006The lamp emits radiation with a very broad wavelength range, from the ultraviolet to the infrared; accordingly, a filter that allows only the radiation of the intended wavelength to pass is installed and interposed between the lamp and the skin.

0007During operation, the lamp emits heat and accordingly gets hot and also heats the skin excessively.

0008In currently commercially available devices, the handpiece in which the lamp is mounted is cooled by means of a suction circuit; the skin of the patient is located proximate to the filter that shields the light source and is therefore struck by an intense flow of heat. The document <patcit id="pcit0001" dnum="WO0343514A"><text>WO 03/43514</text></patcit> discloses such a device, and this document discloses the preamble of claim 1.

0009It should be noted that the filter can be touched both intentionally (for example by inserting a finger in the front opening from which the light flashes exit) and unintentionally (for example by treating a curved skin portion and pressing the handpiece excessively against said skin, one runs the risk of contact between the skin and the surface of the filter).

0010Contact with the filter (which can reach high temperatures) certainly entails skin burns: therefore, this apparatus must be used with great skill and cannot be left unattended in the presence of the patient (especially after use, when the filter is still hot and burns are possible if it is handled incorrectly).

0011The lamp and the filter constitute an assembly by means of which it is possible to treat only some aesthetic problems: it is convenient to associate various filters with a same type of light source or to vary both the source and the filter to obtain a series of assemblies suitable for all kinds of skin and for all kinds of treatment.

0012Currently, the entire handpiece is replaced by adopting the one that is most suited for the type of skin and the type of treatment: this entails the purchase of a certain number of handpieces, which however are very expensive and bulky.

0013There are constructive solutions which use interchangeable lamp-filter assemblies: rapid replaceability allows far easier use, but over time it can entail wear of the parts that slide with respect to each other during replacement, rendering the coupling of the assembly to the handpiece scarcely stable (see, for example, <patcit id="pcit0002" dnum="WO2004096072A1"><text>WO 2004/096 072 A1</text></patcit>).

0014The aim of the present invention is to obviate the cited drawbacks and meet the mentioned requirements, by providing a light irradiation unit in which contact with the filter is not possible and in which it is possible to ensure rapid replacement and anchoring of the filter and the lamp.

0015Within this aim, an object of the present invention is to provide a unit in which localized cooling of the handpiece is provided in order to keep at a low temperature all the parts that make contact with the operator and the patient.

0016Another object of the present invention is to provide a unit that is simple, relatively easy to provide in practice, safe in use, effective in operation, and has a relatively low cost.

0017This aim and these and other objects that will become better apparent hereinafter are achieved by a light irradiation unit, according to the invention, that has the features set forth in claim 1. Other advantageous features of the invention are set forth in the dependent claims.

0018Further characteristics and advantages of the present invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of a light irradiation unit, illustrated by way of non-limiting example in the accompanying drawings, wherein: <ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">Figure 1</figref> is a top perspective view of a handpiece of a unit according to the invention;</li><li><figref idref="f0001">Figure 2</figref> is a partially sectional bottom perspective view of a handpiece of a unit according to the invention;</li><li><figref idref="f0002">Figure 3</figref> is a bottom perspective view of a handpiece during the extraction of a cartridge of a unit according to the invention;</li><li><figref idref="f0003">Figure 4</figref> is a sectional front view of a handpiece of a unit according to the invention, in which the half-shells are spaced;</li><li><figref idref="f0003">Figure 5</figref> is a sectional front view of a handpiece of a unit according to the invention, in which the half-shells are closed together;</li><li><figref idref="f0002">Figure 6</figref> is a top rear perspective view of a handpiece of a unit according to the invention, in which the half-shells are spaced;</li><li><figref idref="f0004">Figure 7</figref> is a bottom front perspective view of a handpiece of a unit according to the invention, in which the half-shells are closed together;</li><li><figref idref="f0004">Figure 8</figref> is a sectional rear view of a unit according to the invention, in which the half-shells are closed together;</li><li><figref idref="f0005">Figure 9</figref> is a perspective view of a lamp of a unit according to the invention;</li><li><figref idref="f0005">Figure 10</figref> is a plan view of a parabolic reflector of a unit according to the invention;</li><li><figref idref="f0005">Figure 11</figref> is a front top perspective view of a cartridge of a unit according to the invention;</li><li><figref idref="f0005">Figure 12</figref> is a bottom rear perspective view of a cartridge of a unit according to the invention.</li></ul>

0019With reference to the figures, the reference numeral 1 generally designates a light irradiation unit.

0020The unit 1 is constituted by a handpiece 2, which is connected by means of a multicore cable 3 to a control processor 4.

0021The handpiece 2 has an elongated shape, with smooth and radiused surfaces; at the rear, above the hole for the insertion of the cable 3, there are through slots 5. The actuation buttons 6 are provided in an upper region, at the central portion of the handpiece 2.

0022Each handpiece 2 is constituted by two half-shells 2a and 2b, which are mutually coupled by means of at least one screw 2c, which passes through the half-shell 2a and engages within an appropriately provided seat of the half-shell 2b.

0023A cartridge 7 is accommodated in the front part of the handpiece 2 and is provided with a plurality of front openings 8 and with at least one rear slot 8a (the openings 8 and the slot 8a allow the passage of air within the cartridge 7). The cartridge 7 has the appearance of a block, with a flat bottom 9 made of a material that is not transparent to light radiation. Plates 7a are applied to the cartridge 7 and are constituted by a flat mask 10 provided with an opening 11. The cartridge 7 has, in an upper region, a transparent screen, the filter 12, which has a rectangular area with sides that measure respectively 50 and 30 mm; the filter 12 can be made of materials such as glass, quartz and sapphire but also of other plastic or ceramic materials or of other kinds of material having particular filtering actions with respect to light radiation. Beyond the filter 12, also above the cartridge 7, there is a phototype detector 13.

0024In the rear part of the cartridge 7 there are pins 14 for connection to the handpiece 2, which are suitable to be coupled electrically to the connection socket 14a of the handpiece 2.

0025The cartridge 7 is constituted by a parabolic reflector 15. Inside the parabolic reflector 15 there is a receptacle 16 for a lamp 17, which is shaped like two parallel and mutually proximate cylinders which are radiused at two ends and end, at their opposite ends, with respective electrical contacts 18. The patient can be subjected to light radiation having a wavelength comprised between 1 and 2000 nanometers.

0026A cooling fan 19 is installed longitudinally inside the handpiece 2 in the rear part: when the fan 19 is active, it aspirates air through the holes 5 and conveys it through a duct (delimited between the bottom 9 of the cartridge 7 and the region that surrounds the lamp 17) toward a front opening constituted by the slots 8.

0027The entire cartridge 7 is detachable and can be replaced with other cartridges 7 that have different filters 12, suitable for performing different therapies. For removal, it is necessary to resort to the use of a wrench C, which engages in the head of the screw 2c: by loosening the screw 2c, the two half-shells 2a and 2b are moved mutually apart and the cartridge 7 is disengaged from the clamping action, allowing its extraction; the new cartridge 7, once arranged within the half-shells 2a and 2b so that the pins 14 engage in the connection socket 14a, is fastened between the half-shells 2a and 2b, preventing its movement, by re-tightening the screw 2c with the wrench C. A plate 7a is accommodated and superimposed above the cartridge 7, is made at least partially of a material that is permeable to light radiation, and is designed to prevent direct contact of the skin of the patient with the surface of the filter 12. The surface of the filter 12, although being separate from the lamp 17, is heated considerably by said lamp, and this makes it potentially dangerous for the skin of the patient. The presence of the plate 7a, which in turn is separated from the filter 12 by means of an air gap (through which the air is conveyed forcibly by means of the fan 19), provides assurance of the patient against the risk of bums. The plate 7a is flat and is provided with two perimetric bands 7b, which are arranged at right angles thereto and are provided with end protrusions 7c for anchoring to the side walls of the cartridge 7; the cartridge 7 has, along its side walls, proximate to the open surface, from which the filter 12 can be accessed, a pair of longitudinal grooves 7d, which are suitable to accommodate stably the protrusions 7c.

0028The phototype detector 13 is a very important accessory, which is used to detect the type of skin being treated at a given moment. There are various kinds of skin, according to a scale defined by Fitzpatrick; this scale defines the reaction of the skin subjected to the emission of light, such as for example sunlight. This classification defines six types of skin: a first type, which always bums; a second type, which bums occasionally; a third type, which bums and occasionally tans; a fourth type, which tans and occasionally bums; a fifth type, which tans; and a sixth type, which tans and does not bum.

0029The phototype detector 13 allows to diagnose the patient's phototype, so as to subject the patient to the most suitable therapy.

0030The phototype detector 13 is arranged near the lamp 17, but can also be arranged in other parts or separately from the cartridge 7.

0031A temperature sensor is inserted in the cartridge 7 and is connected to the processor 4 for controlling and lighting the lamp 17; this allows to check that the lamp 17 does not exceed a certain temperature that might damage the cartridge 7 and/or bum the skin of the patient being treated. The temperature sensor can be electronic, electric, electromechanical or of any type that has these functions.

0032Each cartridge 7 differs according to the type of filter 12 fitted therein; in order to recognize it, the cartridge 7 is provided with an electronic recognition apparatus.

0033Since the filter 12 is a non-detachable part of the cartridge 7, the problem of recognizing the filter 12 is reduced to the problem of recognizing the electric circuit of the cartridge 7 on which it is installed.

0034The operation of the invention is as follows: once the therapy to which the patient is to be subjected is known, the type of cartridge 7 suitable for said therapy is chosen and is inserted in the handpiece 2 by sliding the bottom 9 into the appropriately provided receptacle and by making the pins 14 mate with the socket 14a; the filter detector indicates on a display the type of filter that is installed.

0035By pressing one of the buttons 6 arranged on the top of the handpiece 2, the phototype detector 13 is activated and identifies the characteristics of the skin of the patient, checking the reflection on the skin of the light radiation, emitted by a light source, by means of a photodiode. The result of the test is indicated on the display.

0036Depending on the characteristics of the skin of the patient, the operator selects the most suitable program and starts the treatment, keeping the handpiece 2 orientated so that the lamp 17 faces the portion of skin to be treated.

0037The temperature of the lamp 17 is monitored constantly by the temperature sensor, which sends a signal that is proportional to the temperature of the lamp 17 to the processor 4, which adjusts the duration and frequency of the flashes in succession to avoid overheating. If a temperature limit is reached, the processor 4 disables the operation of the lamp 17.

0038During operation, the cooling fan 19 operates and keeps the temperature of the lamp 17 low.

0039The simultaneous presence of cooling means that act locally (fan 19) and of a plate 7a that separates the skin of the patient from the high-temperature surfaces makes the handpiece very simple to use and protects the patient, avoiding the risk of bums.

0040The possibility to replace the cartridges 7 makes it easier for operators to perform the treatment; moreover, the need to fasten the inserted cartridge 7 each time gives the advantage of always achieving the correct insertion of the cartridge 7 in the handpiece 2, making sure that it cannot detach accidentally and fall (and thus certainly be damaged) or provide a poor contact between the pins 14 and the socket 14a, with consequent possible malfunction and damage of the circuits.

0041It has thus been shown that the invention achieves the intended aim and objects.

0042The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept.

0043For example, it is possible to block the cartridge 7 by way of other fastening means. By using a toggle lever that is articulated to a half-shell 2a and engages in a protrusion of the other half-shell 2b, it would be possible to block the cartridge 7 firmly, both due to the mutual fastening of the half-shells 2a and 2b and due to the interference between the toggle lever and the cartridge 7.

0044Other equally valid embodiments may provide for the presence of grub screws (or regular screws) that are rigidly coupled to the surface of the half-shells 2a and 2b and engage, by screwing, respective receptacles formed in the side walls of each cartridge 7.

0045Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.