AU2015289072A1 - Pulsed light therapy assembly - Google Patents

Abstract

Assembly including: a pulsed light therapy machine (1) including a handset (4) including a flash lamp and a first absorbent filter (12) for filtering the light emitted by the flash lamp before it exits the handset; and a pair of glasses or a mask for protecting the operator, including a second absorbent filter for filtering incident light, the assembly being characterized in that the overall transmission of visible and infrared light through the first and second filters is sufficiently low in the emission range of the HS that the operator is not discomforted visually by the emission nor harmed by the infrared light.

Description

WO 2016/009008 1 PCT/EP2015/066343

Pulsed light therapy assembly

The present invention relates to pulsed light therapy assemblies and to the corresponding methods of implementation.

Polychromatic pulsed light (PPL) machines, which are also referred to as 5 intense pulsed light (IPL) machines, are widely used at the present time in various cosmetic and dermatological applications, and in particular for epilation.

They generally comprise a base unit and a handset that is connected to the base unit by a flexible cable. The handset includes a flashlamp that generates high-intensity light pulses. The spectrum of these pulses, before filtration, extends from the ultraviolet to 10 the infrared, and the handset includes an optical filter that lets pass essentially the visible light and the near-infrared, with for example a peak toward 820 nm.

When using the machine, the operator wears glasses that attenuate the intensity of the emitted flashes, while allowing him to see sufficiently well to be able to position the handset precisely on the region to be treated. 15 Existing protective glasses have absorbing lenses of a green color that is more or less dark. With the lightest lenses, it is frequent to see the operator get into the habit of closing his eyes just before pressing on the trigger that triggers the emission of a flash, because even if the optical guide is applied firmly against the skin, leakages of light may be sources of visual discomfort, or even of danger for operators that practice all day long. 20 Surprisingly, the market for IPL machines has grown considerably over the last few years without this drawback being rectified.

Contrary to lasers the use of which is subject to the user wearing glasses meeting standard EN 207, there is presently no eye protection standard that must be met when using IPL pulsed light, the particularity of which is the emission of intense light over 25 a wide spectrum ranging from the visible to the infrared.

The green protective glasses presently used with IPL machines meet only standard EN 166 that essentially specifies the mechanical strength of the glasses. These glasses do not satisfactorily protect the retina of the eye. WO 2016/009008 2 PCT/EP2015/066343

Certain machines offer the possibility of an operating mode in which the pulsed light is emitted in bursts. In this case, if a pushbutton or a pedal is held down the handset emits a succession of automatic flashes that are very closely spaced in time, this having the advantage of allowing the user to treat a zone to be treated while continually moving the handset thereover. Treatment time is decreased as a result. In contrast, it is no longer possible for the user, if he so desires, to close his eyes during the treatment, without decreasing the precision of the movement. A greater visual discomfort may result, obliging the user to wear glasses with darker lenses.

It has been sought to remedy this problem by providing, in patent application US 2010/0045882 Al, liquid-crystal glasses, the obturation of which is controlled by an action exerted on the trigger of the handset to trigger a flash. The glasses include a control circuit that is informed that a flash will be triggered and the liquid crystals then pass from a transparent state to an opaque state, then return to the transparent state after the emission of the flash.

Such a system is relatively complex and expensive, and of a substantial weight. It is furthermore difficult to completely remove the risk of failure of the glasses. Also, the emission of the flashes must absolutely be prevented if the latter do not occur when the glasses are in the occulted state.

The invention aims to further improve pulsed light therapy assemblies so as to allow individuals to be treated in complete safety while simultaneously offering the operator the best possible visual comfort, in particular in the case where the flashes are emitted in bursts.

It achieves this aim by virtue of an assembly including: - an in particular cosmetic or dermatological pulsed light therapy machine including a handset including a flashlamp and a first selective absorbing filter for filtering the light emitted by the flashlamp before it exits the handset, - a pair of glasses or googles for protecting the operator, including a second selective absorbing filter for filtering the incident light.

The overall transmittance of visible and invisible (IR) light through the first and second filters is preferably sufficiently low that the operator is not visually WO 2016/009008 3 PCT/EP2015/066343 discomforted by the emission of a flash or harmed by the infrared light. This overall transmittance is preferably 10% or less in the range 580 nm to 1200 nm, better still 1% or less, and even better still 0.1% or less in the same range. This range may substantially correspond to the width of the spectrum of the light emitted by the machine.

The expression “harmed by the infrared light” must be understood to mean that the infrared radiation that reaches the user is higher than the safe limits in force, such as defined in standard EN62471. This corresponds to an energy E(ir) < 18000.texp-0.75 (W/m2). The level of protection sought in the invention is preferably much higher than the limit required by this safety standard. The maximum energy that reaches the retina is preferably at least ten times lower than the limit imposed by the standard.

By "overall transmittance" at the wavelength λ, what is meant is the product of the transmission coefficients at the wavelength λ of each of the filters. For example, if the transmission coefficient at 650 nm of first filter is 10 _1, and that of the second at 650 nm is 10 '3, the overall transmittance at 650 nm is 10 Λ

Outside of the range of emission of the machine, and preferably in the spectrum of the visible, the transparency of the protective glasses must remain sufficiently high, in particular higher than 10%, better still higher than 95% and ideally in the vicinity of 100%, so as to keep a good view of the environment and of the zone to be treated. Transparency is defined as the ratio of the intensity of the light that exits from the filter to the intensity of the light that enters therein. The second absorbing filter thus preferably has a transparency higher than 10% and better still than 95% outside of the range of emission of the machine.

The invention is a particularly elegant and economical way of improving the visual comfort of the operator and treated individual, and permits flashes to be emitted in bursts while also allowing the handset to be positioned with precision as the user may continue to visually monitor its movement unhindered.

Preferably, the invention allows, in particular with an attenuation coefficient of 106, a level of protection to be obtained for IPL machines that is identical to that required by the standard EN 207 for lasers and in particular that is, in the infrared, enough to meet the retinal thermal hazard limit - weak visual stimulus (780 nm - 1400 nm). By virtue of the level of protection provided by the invention, it becomes possible for users to focus on the working zone, pupils dilated, without danger. WO 2016/009008 4 PCT/EP2015/066343

Preferably, the absorbing filter of the glasses or of the googles is of blue color. The absorbing filter of the machine may be arranged to block visible light of wavelength shorter than λς nm, with λς for example equal to 600 nm. This absorbing filter may be of red color.

Preferably, the absorbing filters of the glasses or of the googles on the one hand and that of the handset on the other hand are chosen so that each has a passband with a sufficiently steep break. Preferably, blockage of the light of 10 to 90% of the break occurs in less than 100 nm, or better still in less than 50 nm. This makes it possible to more easily avoid overlap of the spectra. Absorption filters have the advantage of delivering the same attenuation of light whatever the angle of incidence of the light ray.

Preferably, the handset includes upstream of the absorbing filter a dichroic filter. The latter may have substantially the same absorption spectrum as the first absorbing filter, for example the band 400 nm to 650 nm. This filter decreases the risk of degradation of the absorbing filter.

Preferably, the machine is arranged to emit a burst of flashes. It is for example a question of flashes emitted at a firing frequency of at least 1 Hz, over a length of time that typically ranges from 1 s to 1000 s for example.

The absorbing filter of the glasses or of the googles preferably has a transmission coefficient lower than 1% for λ < 400 nm and for λς < λ < /<ι, with λς equal to 600 nm for example and with /<i preferably comprised between 850 and 1200 nm and in particular equal to 850 nm for example. It is possible for λ comprised between λς and /<i to have an overall transmittance lower than 1%, better still than 0.1% and even better still than 0.01%, with λς shorter than 850 nm and preferably equal to 600 nm and /<i> λς and preferably equal to 850 nm.

The second absorbing filter, i.e. that of the glasses, preferably has a transmission coefficient of 90% or more at at least one wavelength shorter than λς, with λς for example equal to 600 nm, and of 10% or less for those wavelengths in the visible domain that are 600 nm or longer, i.e. in the range extending from 600 nm to 750 nm.

The emission spectrum of the therapy machine is preferably substantially zero for λ < 0.9.λς, with λς equal to 580 or 600 nm for example, in particular 1 W/cm2 or less and 10 W/cm2 or more for 650 < λ < 800 nm and better still 640 < λ < 830 nm, and in WO 2016/009008 5 PCT/EP2015/066343 particular 500W/cm2 or more and better still 1000 W/cm2 or more for at least one wavelength in the interval 600 nm a 850 nm.

Generally, the emission spectrum may extend up to 1200 nm, and the peak power may range up to 2000 W/cm2. In this case, the wavelength /Ki at which the glasses 5 cease to block light will be 1200 nm.

The transmission coefficient of the glasses or of the googles may be 20% or more at at least one wavelength in the visible and preferably in the range 400 nm to λς, with λς longer than 400 nm and preferably equal to 600 nm.

In variant embodiments of the invention it is possible, for example, for λς to be 10 comprised between 530 nm and 710 nm and for example equal to 530 nm, 610 nm or 710 nm.

Yet another subject of the invention, according to another of its aspects, is the use of the glasses or googles such as defined above to filter the light emitted by the handset. 15 The invention will possibly be better understood on reading the following description of an exemplary nonlimiting embodiment thereof, and on examining the appended drawing, in which: - figure 1 schematically shows a therapy assembly according to the invention, - figure 2 schematically and partially shows the optical portion of the handset, 20 - figure 3 shows protective googles, - figure 4 is an exemplary emission spectrum of the therapy machine, - figure 5 shows an exemplary passband of the absorbing filter of the glasses in known therapy assemblies, and - figure 6 shows an exemplary passband of the absorbing filter of the glasses 25 in an assembly according to the invention, the emission spectrum of the machine of which corresponds to that reproduced in figure 4.

The pulsed light therapy machine 1 shown in figure 1 includes a base unit 2 that contains an electrical generator and a handset 4 that is connected to the base unit by a flexible cable 5. WO 2016/009008 6 PCT/EP2015/066343

The handset 4 may be cooled by a flow of water using supply and return ducts integrated into the flexible cable 5.

The handset 4 includes, as illustrated in figure 2, a flashlamp 10 that is connected to the electrical generator, a dichroic filter 11 and an absorbing filter 12 that is placed downstream of the filter 11.

The filters 11 and 12 may be placed upstream of an optical duct 13 that guides the light to an exit face 14 of the light, to be applied to the zone to be treated.

The energy spectrum of the light emitted by the handset for example has the shape shown in figure 4.

The flashlamp 10 is cooled by a flow of water and the dichroic and absorbing filters are preferably produced in an integral form so as to be cooled by this flow of water.

The dichroic filter 11 is advantageously deposited on the absorbing filter 12 by a vacuum deposition technique, thereby guaranteeing an intimate contact between the two and highly effective cooling of the absorbent filter 12 by the water.

The dichroic filter 11 may be produced with the absorbent filter 12 in accordance with the teaching of patent application US2011/0071510 A1 in the name of the applicant.

The optical duct 13 is for example removably fastened to the casing of the handset 4 in order to allow optical ducts of various cross sections to be used depending on the nature of the therapy.

The flashlamp 10 may be contained in a cartridge that is removably received in the casing of the handset, in order to facilitate its replacement, as for example described in patent EP 1 906 856 A1 of the applicant.

The handset 4 includes a switch 16 controlled by the user to trigger the flashes. A pedal may be used in parallel with the switch 16.

The characteristics of the flashes, in particular the energy of the flashes and their emission frequency where appropriate, may be controlled from a user interface 17 provided on the base unit.

It is particularly advantageous for the flashes to be emitted in bursts with a relatively high frequency.

For example, the flashes are emitted with a frequency of 1 Hz or more or better still of 5 Hz or more when the user presses on the switch 16 for triggering the flashes. The WO 2016/009008 7 PCT/EP2015/066343 fluence of a flash is preferably 3 J/cm2 or more or better still 6 J/cm2 or more and it is for example comprised between 3 and 16 J/cm2.

The flashlamp 10 is preferably a flash tube made of quartz and filled with xenon.

The passband of the absorbing filter 12 is preferably chosen so as to remove as effectively as possible radiation of wavelength shorter than or equal to λε; with λς preferably equal to 600 nm.

The passband of the dichroic filter 11 is preferably chosen to remove radiation of wavelength shorter than or equal to λς and infrared radiation, especially that of wavelength longer than about 850 nm.

The characteristics of the filter 12 are chosen so as to preferably obtain for its passband a relatively steep break between the absorption domain, at wavelengths shorter than or equal to λς. and the domain that is passed, at wavelengths longer than or equal to λς.

This break may be characterized by a transition of 10 to 90% in a spectral band narrower than 100 nm and better still narrower than 50 nm.

The therapy machine 1 is used with eye protecting means that are worn by the operator who handles the handset 4, said means for example consisting of glasses 25 including a frame 20 and lenses 21.

The latter have, according to the invention, filtration characteristics that are complementary to those of the machine 1.

Thus, the light emitted by the handset is sufficiently filtered by the glasses 25 for the residual light that reaches the eyes of the operator not to be a source of discomfort, and for the infrared radiation not to be a danger.

The passband of the glasses 25 is chosen so that the absorptance is low at the wavelengths at which the absorptance of the filter 11, 12 is high, and high at the wavelengths at which the absorptance of the filter 11, 12 is low.

Thus, the transmittance of the absorbing filter of the glasses 25 is preferably 1% or less in the range λς to u\ in which the machine 1 emits a substantial amount, and 10% or more at at least one wavelength in a range of wavelengths shorter than λς, with λς preferably equal to 600 nm and /<i preferably equal to 850 nm.

Figure 6 shows an example of the passband that the glasses 25 could have, said passband being adapted to the emission spectrum shown in Figure 4. WO 2016/009008 8 PCT/EP2015/066343

In such a situation, the lenses 21 of the glasses 25 appear of blue color and the absorbing filter 12 of red color.

By way of comparison, figure 5 shows the transmission coefficient of glasses currently sold with IPL therapy machines, and that pose the problems mentioned in the 5 introduction.

The glasses 25 may be selected from the laser safety glasses sold by certain manufacturers.

In the illustrated example, it is thus possible to choose those sold by LASERVISION under the commercial reference FxxPlE02. 10 Of course, when the emission spectrum differs from that illustrated in figure 4, the passband of the glasses 25 is modified accordingly.

The invention is not limited to the example that was just described.

It is possible for example to replace the glasses 25 with protective googles similar to ski goggles, for example such as illustrated in figure 3. 15 The person that receives the therapy may be equipped with the same glasses 25.

The absorbing filter of the therapy machine may consist of a single part or of a plurality of parts placed optically in series. The same goes for the absorbing filter of the glasses. 20 The value λς may be other than 600 nm and may, in particular, be lower or higher and, for example, equal to 510, 610 or 710 nm and /<i may be other than 850 nm and may, in particular, be higher than 850 nm.

The second absorbing filter, namely that of the glasses, may be a unitary object made of a single bulk-treated transparent material or as a variant two adhesively bonded 25 filters having different specific absorption bands. For example, a first (organic or mineral) lens that filters the IR and a second (organic or mineral) lens that filters wavelengths in the visible domain are adhesively bonded.

The expression “including a” must be understood as being synonymous with “comprising at least one” unless otherwise specified.

Claims (12)

1. An assembly including: - a pulsed light therapy machine (1) including a handset (4) including a flashlamp (10) and a first absorbing filter (12) for filtering the light emitted by the flashlamp before it exits the handset, - a pair of glasses (25) or googles for protecting the operator, including a second absorbing filter (21) for filtering the incident light, assembly characterized in that the overall transmittance of visible and infrared light through the first and second filters is sufficiently low in the range of emission of the HS that the operator is not visually discomforted by the emission of a flash, or harmed by the infrared light, the second absorbing filter having a transmittance of 1% or less in the range λε to /.d of emission of the machine.

2. The assembly as claimed in claim 1, the second absorbing filter (21) having a transparency higher than 10% and better still than 95% outside of the range of emission of the machine, said range preferably extending from 600 nm to 850 nm.

3. The assembly as claimed in claim 1 or 2, the overall transmittance in the range ric to rid being lower than 0.1% and better still lower than 0.01%, with λς shorter than 850 nm and preferably equal to 600 nm and λ<ι> λς and preferably equal to 850 nm.

4. The assembly as claimed in any one of claims 1 to 3, the absorbing filter (21) of the glasses (25) or of the googles being of blue color.

5. The assembly as claimed in any one of claims 1 to 4, the absorbing filter (21) of the glasses (25) or of the googles having a transmission coefficient lower than 1% both for λ < 400 nm and for λς< λ < λά, with λς preferably equal to 600 nm and λd preferably comprised between 850 and 1200 nm and preferably equal to 850 nm.

6. The assembly as claimed in any one of the preceding claims, the handset including upstream of the absorbing filter (12) a dichroic filter (11).

7. The assembly as claimed in any one of the preceding claims, the machine being arranged to emit a burst of flashes, in particular flashes emitted at a firing frequency of at least 1 Hz and better still 10 Hz, in particular over a length of time that ranges from 1 s to 1000 s.

8. The assembly as claimed in any one of the preceding claims, the second absorbing filter (21) having a transmission coefficient of 10% or more at at least one wavelength shorter than λς, and of 1% or less at those wavelengths in the visible domain which are longer than or equal to λς. with /.c shorter than 850 nm, and preferably with λς equal to 600 nm.

9. The assembly as claimed in any one of the preceding claims, the emission spectrum of the therapy machine (1) being substantially zero for λ < 580 nm and better still λ ^ 600 nm, and 100 W/cm2 or more for 650 < λ < 800 nm and better still 640 < λ < 830 nm, and in particular 500 W/cm2 or more and better still 1000 W/cm2 or more at at least one wavelength in the interval 600 nm to 850 nm.

10. The assembly as claimed in any one of the preceding claims, the transmission coefficient of the glasses (25) or of the googles being 20% or more at at least one wavelength in the visible and preferably in a range 400 to λς, with λς longer than 400 nm, and preferably with λς comprised between 530 and 710 nm, and preferably with λς equal to 600 nm.

11. The assembly as claimed in any one of claims 1 to 10, the second filter (21) including an infrared-filtering lens adhesively bonded to a lens that filters in the visible.

12. The use of the glasses or googles such as defined in any one of the preceding claims to filter the light emitted by the handset.