Uv radiation device

FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

©) Publication number: 2 321 908 (Use only for reproduction orders).

PARIS.

REQUEST

OF PATENT INVENTION © N ° 75 25885 © Apparatus for surface irradiation with ultraviolet.

(§) International classification {Int. Cl.²). A 61 N 5/06.

(2) Date of filing ............................. August 26, 1976, 4:09 p.m.

© © © Priority claimed: Patent applications filed in the Federal Republic of Germany on August 1975, η. P 25 37 855.6, January 30, 1976, η. P 26 03 460.6 and on May 31, 1976, η. P 26 24 297.7 and additional patent application filed on F ebruary 12, 1976, η. P 26 05 487.5 on behalf of the applicant.

@ Date of making the request available to the public ............ BOPI - "Lists" n. 12 of 25-3-1977.

©) Applicant: WOLFF Friedrich, residing in the Federal Republic of Germany.

(72) Invention of:

(73) Holder: Idem ©) @ Agent: Cabinet Plasseraud.

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Sale of booklets at IMPRIMERIE NATIONALE, 27, rue de la Convention - 75732 PARIS CEDEX 15

The present invention relates to an apparatus for surface irradiation by the ultraviolet (W) of a subject, comprising at least one radiation exit opening, at least one source of UV radiation placed behind and an associated reflector assembly.

Apparatuses for the ultraviolet irradiation of a human body on the surface (this term being used as opposed to irradiation in volume), are generally in the form of small domestic apparatuses which irradiate only a part of the body, in particular the face and the bust or in the form of '' solariums which radiate the whole body. The person to be irradiated must be at a distance from the radiation exit window which, in the case of small household appliances generally made as table appliances, is between 60 and 100 cm and, in the case of solariums '' which are generally mounted permanently above a (relaxation) chair, between 120 and 200 cm. The radiation source for small household appliances is, in general, a high-pressure mercury vapor lamp. Solariums generally have three, each lamp has a power of 100 to 150 W for small domestic appliances, 150 to 250 W for domestic solariums and 300 to 350 W for large solariums.

UV irradiation devices of this kind are often only used for tanning. Long before tanning begins, we observe a whole series of other unfortunate biological phenomena, firstly erythema or sunburn, followed by peeling and keratinization. Since the threshold dose which causes erythema is already reached, depending on the density of the radiation prevailing on the surface of the skin, after a few minutes, but at this time practically no tanning of the skin is necessary. 'is obtained, the irradiation must be repeated a large number of times, the irradiation time possibly increasing a little each time. But, even then, you cannot achieve a tan like that produced by the sun.

The invention aims to provide an ultraviolet irradiation device on the face, of the type defined above with which the desired tan is obtained - with a significantly lower number of irradiations, before arrangement even with a single irradiation.

For this, the UV radiation source and the reflector assembly are produced so as to produce, in the radiation exit window or close to it, a high density field * 2321908 of irradiation with UV rays of the type A, of area corresponding to the desired irradiation surface; a filter which removes most of the UV rays of types B and C is inserted in the path of the rays; and the UV radiation source has a sufficiently low calorific power, or a filter stopping the thermal radiation and interposed in the path of the rays is provided so that the thermal effects on a subject in this field remain within the admissible range.

UV radiation in region A is by far the main responsible for the tanning of the skin which only occurs if a quantity of UV energy (A) is applied to the surface of the body above a relatively high threshold. Experiments have shown that the threshold value, which obviously varies depending on the individual, is around 7.5 to 10 wA / cm2. In order to be able to apply such a high dose of radiation with an irradiation time that is still tolerable, the device is designed in such a way that the subject does not have to be at the usual great distance, but on the contrary can stay much closer from the radiation exit window or even right in front of it, where, thanks to the short distance from the UV radiation source and the reflector assembly, there is a high density of UV radiation (A). The filter absorbing UV (B) and UV (C) radiation eliminates the danger of an erythema, which is all the greater with current devices as the person irradiated gets closer. The choice of a low-power UV radiation source or the use of a filter stopping the heat radiation means that the subject to be irradiated is not inclined to move away from the ray exit window as a result of excessive heating. The smaller the distance, the higher the density of the radiation in general, but the smaller the area where the radiation flux is relatively high. Thanks to an appropriate production of the UV source (for example with regard to shape, size and - if several UV lamps are used - their arrangement) and / or an appropriate production of the reflector assembly (for example as regards its shape, size and arrangement) it is also possible in each case to create a sufficiently large area where the flux of UV radiation (a) is relatively high in the immediate vicinity of the radiation exit window. In particular, this field can be chosen sufficiently wide to be able to irradiate the whole body of a subject. For example, for a high density of UV radiation (A), of around 4 mW / cm 2, a tan is obtained from an exposure of 20 minutes. With a higher density of UV radiation (A), of about 5 to 30 mW / cm2, the irradiation time is reduced accordingly. For a lower radiation density, a longer irradiation time is required, for example one hour for 2 mW / cm2, which can also be subdivided into several separate irradiations unless the tanning threshold for UV energy ( A) was lowered by sensitizers.

Since with such an irradiation device a single irradiation is sufficient in the most favorable case for a lasting tan, the treatment is clearly simplified. The user does not have to fear a sunburn, nor to waste the time necessary for several irradiations. This irradiation device is, in particular, capable of being placed in public premises, such as swimming pools, leisure center, etc., because the public decides more easily in the case of a single irradiation than in the case of several irradiation effective in several days.

In an advantageous embodiment, the source of ultraviolet radiation is constituted by 5 to 20, preferably 10 to 12, tubular low-pressure mercury vapor lamps placed parallel side by side and very close together, with power, in the UV region (A) of at least 5 W / m of tube and the reflector assembly is made up of an equal number of gutter-shaped reflectors which each surround one of the tubular lamps at an angle of at least 180 ° around the axis.

Low pressure mercury lamps have such a low calorific value that they hardly heat the person to be irradiated. However, they have power in the region

UV (A), significantly lower than that of other sources of UV radiation. Therefore, they are placed relatively close to each other and are each provided with a reflector. In this way, a uniform high-density irradiation field in the region> n UV (A) is obtained near the radiation exit window, the dimensions of which can be determined by the number and length of the lamps low pressure mercury.

The higher the UV power (A) emitted, the faster the desired tan is obtained. Consequently, each low pressure mercury lamp is advantageously given a power

UV (A) of at least 8 W / m of tube length. We can even reach values ​​of 10 W / m and more.

The use of low pressure mercury lamps as long as possible facilitates the irradiation of the whole body. Long lamps of at least 1 meter should be used. A tube length of 1.50 m is particularly advantageous since it is possible under these conditions, for the necessary ignition voltage, simple and economical ignition ballasts. The optimal length for full body irradiation is 1.80m as it allows the entire total body length to be irradiated for most humans.

The 1.50 m long lamps, which emit such a power (UV (A)), previously had a total power of more than 100 V (about 120 W) but can currently be produced with a power of 80 W because of the progress in the doping technique.

The spectral data chosen, in particular the UV power, (A), must not vary during operation. Since variations in the operating temperature normally cause drift, so far cooling fans have been used. These can be eliminated when the low-pressure mercury lamps contain a chemical additive, for example an amalgam, which keeps the UV power (A) and the energy spectrum almost constant, regardless of the operating temperature.

To obtain a sufficient density of UV radiation (A), it is preferable that the distance between low pressure tubular mercury lamps. Neighbors does not exceed their diameter.

The reflectors advantageously have roughly parallel side walls which project forward from the tubular lamps. In this way, the rays emitted laterally forwards by the lamps are deflected towards the area of ​​high density of UV radiation (A).

The rear part of the reflector preferably has a shape reflecting most of the radiation emitted by the rear face of the lamp in the direction of the interval between, this â.LlS S 2L lamp and the side wall of the reflector. A large fraction of the radiation emitted from the lamp towards the rear is used / in this way to produce the desired high density of UV radiation (A) in the field.

The cross section of the rear part of the reflector can be symmetrical with respect to the median plane with a first arc starting in the median plane and having a curvature such that the rays falling on it are deflected in the direction of the interval lying on the same side.

It is possible to connect, to this first arc, a second arc of greater curvature and, to this, a third arc of lesser curvature to the narrowest point of the interval, the curvatures being determined so that the rays falling on the third arc are deflected towards the second arc opposite and from there towards the corresponding interval.

In another embodiment, the source of UV radiation consists of at least one high-pressure mercury lamp having xenon and the filter stopping the heat radiation is a reflector filter which largely reflects the UV radiation (A ), but transmits at least part of the heat radiation and, if necessary, visible light. A high-pressure mercury lamp, like a xenon lamp, emits appreciable UV (A) power, but it also emits a lot of heat. The subject to be irradiated can be protected from it, much better than by a heat-resistant filter screen, using a reflection filter. These reflection filters are advantageously placed to make an angle 20 ° to 50 ° with the direction of the rays and to reflect the desired UV rays (A) in the direction of the irradiation zone disposed laterally. Such a reflection filter can also protect the eyes from being dazzled by the light emitted by the source of ultraviolet radiation.

The high pressure mercury lamp preferably has a UV power (A) of at least 20 W and the reflector assembly comprises for each lamp, a wide angle reflector, in the shape of a trough whose angle d opening is greater than 80 °, preferably greater than 100 °. The reflector with very large aperture distributes on all sides the radiation emitted by the relatively short high-pressure mercury lamp, so as to produce near the exit window of the. radiation from the device a sufficiently large field at high UV density (A). The total power of known high-pressure mercury lamps providing such UV power (A) exceeds 1000 W; it is, for example of 2000 W.

To make such a device for irradiating the whole body, it is recommended to have three high-pressure mercury lamps with the corresponding wide-angle reflectors side by side or one above the other at a distance that is chosen according to the opening angle of the reflectors so that the marginal rays of neighboring lamps intersect at a distance of 10 to 30 cm in front of the ray exit windows.

A tubular xenon lamp can have a UV power (A) of at least 50 W / m in length. The reflector assembly may include one reflector in the form of a gutter per tube. The overall power of known xenon lamps providing such UV power (A), exceeds 1000 W for a 0.40 m tube, it is for example between 1500 and 2500 W; for a tube length of 1.50 m, it is for example 9 kW.

In a preferred embodiment, the filter eliminating by filtering the majority of UV (B) and UV (C) radiation consists essentially of the glass envelope of the lamp. Instead, you can also insert a glass filter screen, for example to form the exit window of the rays of the device.

In another embodiment the filter eliminating by filtering a large fraction of UV (B) and UV (C) radiation can be arranged so that it can be removed from the path of the rays. It can be produced for example in the form of a folding door. It is possible, by removing this filter for a short time from the ray path., Of. direct small doses of UV (B) and UV (C) radiation onto the body in sufficient quantities to produce positive effects such as the formation of vitamin D, immunization against certain diseases or an increase in the quantity of precursors of Elamine or blood supply This short-term withdrawal can also be performed automatically.

In addition, the curved reflecting surface of the reflector can be made, at least in part, in the form of a reflection filter and the source of UV radiation can be covered by a screen on the side opposite the reflector. The reflector plays a dual role under these conditions. It provides, in front of the exit window, sufficiently large areas where intense UV radiation (A) prevails and at the same time it separates part of the annoying radiation from the desired radiation. Unwanted heat and light radiation are moreover directed towards the rear of the reflector, and therefore towards the rear of the device, where they are not a nuisance, and it is therefore even possible to easily remedy any heat development. This screen prevents any heat or light radiation from being directed forward. This screen can also be produced in the form of a second reflector, so that all of the radiation from the UV radiation source is used, but directed through the reflection filter.

It is advisable, to produce a field adapted to the size of a man and with a high density of UV radiation (A), to have the exit window of the rays of the apparatus or the exit windows placed one above the above each other in a vertical plane.

In this way, a subject to be irradiated can place himself very close to the ray exit window, for example on a bearing surface marked or by leaning on a support member predetermining the irradiation distance and preventing any recoil.

The field with a high density of UV radiation (A) which is located very close to and in front of the device is thus used in a particularly simple manner.

It is advantageous in certain cases to provide two vertical planes forming between them an angle close to 90 °, each comprising a radiation exit window or several superimposed exit windows placed near the line of intersection of the vertical planes. In this way a subject can be irradiated not only from the front, but also from the side.

Another possibility to keep the irradiation distance as small as possible is to place the radiation exit window, or several exit windows arranged side by side, in a horizontal plane by orienting them upwards and placing just above, a relaxation tray in one or more pieces and in a transparent material at least for UV radiation (A). Under these conditions, the irradiation distance is practically zero. A roughly opaque filter for UV (B) and UV (C) radiation can serve as a relaxation tray.

It is advantageous, under these conditions, to provide above the relaxation tray, the radiation exit window (oriented downwards) of a UV emitter placed above and / or to provide at least one on the side of the relaxation tray a window for the exit of radiation from a lateral emitter of UV radiation. These additional emitters of UV radiation may have a structure similar to that described above.

It is also possible to place the window (or windows arranged side by side) of the radiation outlet in a horizontal plane, by orienting them downwards and above a relaxation device, the device being able to descend to the -above this device and very close to it, so we can achieve the desired short irradiation distance.

In another embodiment, the window or the adjacent radiation exit windows are in a plane slightly inclined to the horizontal, oriented downwards and placed above a relaxation device. The interval between the relaxation chair is greater on one side of it and makes it possible to reach the chair with a device mounted permanently.

In an advantageous embodiment, the low-pressure mercury lamps, the reflectors, filters, associated ballasts and the switching devices are grouped in a cabinet and form a block, which may also include the cooling fan.

An automatic money device can be part of the operating devices. Building blocks of this kind can be standardized and erected in different places. They can be housed in a wall, grouped in the form of cabins or even incorporated into a piece of furniture.

The invention will be described in more detail with reference to the accompanying drawings which show nonlimiting examples and in which:

Figure 1 shows a horizontal section of a first embodiment of the invention;

2 shows a large-scale section of a low pressure mercury lamp of Figure 1 and the associated reflector;

FIG. 3 represents the relative sensitivity, as a function of the wavelength, of the skin to UV radiation;

FIG. 4 represents the relative distribution, as a function of the wavelength, of the intensity of the radiation of various UV lamps;

FIG. 5 represents a schematic section of a second embodiment of the invention;

Figure 6 shows the use of the embodiment of Figure 7 for full body irradiation;

- Figure 7 shows a third embodiment of the invention;

FIG. 8 represents the internal parts of this embodiment;

FIG. 9 represents an apparatus produced in the form of. cabinet Figure 10 shows an assembly with several irradiation locations;

FIG. 11 represents an irradiation unit with four cabins;

Figure 12 shows a cross section of the assembly of Figure 11;

FIG. 13 represents several relaxation plates for Irradiation;

Figure 14 shows another arrangement of the apparatus; FIG. 15 represents a schematic front view, in partial section, of an apparatus comprising upper and lower emitters of UV radiation;

Figure 16 shows an embodiment in which there are further provided UV emitters on both sides;

FIG. 17 represents a schematic cross section of an apparatus provided with a reflector used in part as a reflection filter.

The apparatus of FIG. 1 comprises a housing 1 in the front face of which is formed a window 2 for the exit of radiation and which comprises, on a curved line a., Ten separate low pressure mercury lamps 3, vertical and parallel, tubular from each other by an interval. These lamps are each 150 cm long and have a power of 120 W or even only 65 W. A reflector 4 in the form of gutters shown diagrammatically is associated with each lamp. Two sources of thermal radiation 5, for example with radiant bars made of electrically heated silicon carbide, are placed at the ends. These sources 5 can be deleted. Ballasts were also housed in box 1

6 for lamps 3, as well as control devices 7, in this case a button 8 for switching on. The glass envelopes of the lamps 3 constitute filters which are almost completely opaque to UV (B) and UV (C) radiation. The outlet window 2 of the shelves is closed by a cover plate 9. We build in this way, a building block that contains all the essential parts.

Doors 11 are mounted on a frame 10 placed at the front and can be opened, to operate the device (position shown). Normally, they dress the device so that it looks like a piece of furniture.

23.21908

The distance b between two neighboring lamps 3 represents approximately 70% of the diameter i of the tubular lamps. Consequently, the distance between the median planes 12 on line a. is equal to (b + c). These median planes are orthogonal to line a. ; the median planes

12a. and 12b of the two outermost two reflectors 4 make an angle between them of less than 80 °, here 45 °. A field 13 of width e = cm and 1.50 m in height corresponding to the length of the lamps is located at a distance d = 10 cm in front of the window.

of exit of the rays. Given the short distance between this field and the lamps 3, the number of these lamps and their chosen power in the region A of ultraviolet, as well as the arrangement of the lamps on the curved line ci and those of the associated reflectors, it is possible to produce in the radiation field 13 a UV radiation density (A) close to 12 mW / cm. This density may decrease slightly towards the edges, but still remains clearly 2 greater than 4 mW / cm.

It is easy to see that one can use, instead of the curved line a ^, a straight line or a broken line in which the reflectors are arranged side by side parallel, in pairs or three by three.

The manufacture of such an apparatus is inexpensive. It can be connected to a normal 10 A socket outlet protected by a fuse and consumes relatively little current.

Figure 2 shows a low pressure mercury lamp 3 and the associated reflector 4. This reflector has approximately parallel side walls 14 which extend forward, beyond the tubular lamp 3. Thus the spokes 15a. emitted laterally forward by the lamp 3 are reflected towards the field

13. The rear part of the gutter-shaped reflector 4 is symmetrical, like its front part. It has a shape such that a large fraction of the radiation emitted by the rear face of the lamp is deflected towards the gap 16 between the lamp and the side wall of the reflector. This comprises for this purpose a first arc with a curvature such that the spokes 15b which fall on it are returned to the interval 16 located on the same side. Arc 17 has a center of curvature 17a. A second arc 18 of greater curvature, the center of curvature of which is 18a., Is connected to the first arc 17. A third arc 19 of lesser curvature, with a center of curvature 19a., Starts from this arc 18 to result in the narrowest part of the interval 16. The curvatures are chosen in such a way that the spokes 15c, falling on the third arc 19 are deflected first towards the and second arc 18 placed opposite / from there returned in the corresponding Interval 16. In this way, it is possible to use almost all of the radiation from the lamp 3 to obtain the high density of UV radiation (A) desired in the field 13.

FIG. 3 is a diagram representing the relative sensitivity Z rel of the skin in the ultraviolet, as a function of the wavelength. The UV range extends from 200 to 400 nm. In practice, it can be subdivided into three sub-regions A, B and C:

200 - 280 nm: UV radiation (C)

280 - 315 nm: UV radiation (B)

315 - 400 nm: UV radiation (A)

Curve 1 represents the sensitivity of human skin with regard to tanning or pigmentation. It extends from approximately 300 nm to 400 nm, with a maximum at approximately 340 nm. Curve II, in phantom, represents the sensitivity of human skin with regard to erythema. It extends across all UV (B) and UV (C) domains, with a maximum around 297 nm and ends around 320 nm. In the apparatus according to the invention, UV (B) and UV (C) radiation are almost completely stopped by filtering, so that a subject irradiated by the apparatus receives practically only UV radiation (A), which is the cause of the tan, but not the rest of the UV radiation that causes the erythema. We can therefore operate with very high doses of UV radiation, because we do not have to take into account the risk of sunburn. The threshold value of 7.5 to 10 Ws / cm, to be exceeded for pigmentation, can therefore be reached in a reasonable time.

. FIG. 4 represents the relative distribution V j of the density of the radiation, again as a function of the wavelength X i. The curve in solid line III represents the shape of this distribution for a mercury lamp at low pressure doped to increase the magnitude of the UV fraction (A). It can be seen that the main radiation emission is in the UV region (A).

The broken line curve IV corresponds to a high-pressure mercury lamp, which has also been doped to increase the magnitude of the UV fraction (A) l · The curve V in dashed line represents what happens with a lamp at xenon. It can be seen that the power is optimally used for the production of UV radiation (A) with a mercury lamp at low pressure. However, the other lamps can be produced with greater powers, so that one can also obtain. appreciable yields in UV radiation (A).

FIG. 5 represents a table-top device 23 whose housing 24 has the shape of a portion of a sphere. It comprises a window 2 for exit of the rays which is closed by a filter 25 which is practically opaque for UV (B) and UV (C) radiation. A high-pressure mercury lamp 25, in the form of a tube about 20 cm long, is placed in the housing. This lamp, whose power is 2000 W, is doped to increase the proportion of UV radiation (A). A wide-angle trough-shaped reflector is associated with it and distributes the radiation from the lamp 26, which constitutes almost a point source, in the field 13 located at a distance in front of the window 2 for the exit of the radiation. The trough-shaped bottom has, in the vicinity of the lamp 26, a circular shape 28 with an arc-shaped cross section which can return the rays emitted towards the rear. The box 24 also contains devices 29, such as inductors, to be connected in series, and control devices 30. This housing rests on a foot 31 and is movable relative thereto.

In the embodiment according to FIG. 6, the irradiation device 32 consists of three boxes 24 provided with the corresponding lamps and reflectors, as shown in FIG. 5. These boxes are fixed to a common support 33 and placed above a relaxation tray. The distance between the housings is chosen so that the adjacent outer marginal rays 35 of the neighboring lamps 26 intersect at a distance of 10 to 30 cm in front of the ray exit windows, Consequently, the field 13 may be located in this region or a little below.

The height of the whole apparatus 32 can be adjusted to facilitate access to a subject to the relaxation tray 34 and to adjust the irradiation distance to its correct value. Two cords 36 pass for this purpose over rollers 37 and are provided with an adjustment device 38.

In the embodiment of FIG. 7, the apparatus is produced in the form of an irradiation tower 39. A casing 41 in the form of a portion of cylinder covered at its upper part with a roof 42, rests on a plate base 40. Control buttons 43 for operating devices 44 (FIG. 8) and slots 45 for introducing money for an automatic money device 46 (FIG. 8) are located on the front face. The ray exit window is covered by a filter glass door 47 provided with a handle 48 and hinges 49. Footprints 50 have been painted in front of the door to define the exact irradiation distance. A series of three superimposed xenon lamps 51, each associated with a roof-shaped reflector 52, is located inside the housing. The xenon lamps are approximately 60 cm long and have a power of 4000 W. The reflectors 52 are again produced in the form of wide-angle reflectors, so that a field of high UV radiation density forms, at a distance of approximately 20 cm in front of the filter glass door 47, d '' about 70 cm wide, 1.8 m high. In addition, there are ballasts 53 and a cooling fan 54 in the housing. A thermal insulation plate 55 is permanently fixed in front of the reflectors. These last two organs are necessary because the xenon lamp emits intense thermal radiation. Even when the filter glass door 47, which stops UV (B) and UV (C) radiation, is open to carry out irradiation throughout the ultraviolet spectrum for a short period, the thermal insulation plate remains effective . It is also possible to use to prevent thermal radiation from reaching the user, in place of this plate acting as a filter, a reflection filter which practically does not reflect the thermal radiation.

FIG. 9 represents the box 1 provided with low-pressure mercury lamps 3 placed behind the outlet window 2 of the shelves, associated with a cabinet or with a shelving unit 56, which is joined to the box so as to form a swivel piece of furniture on a stand 57. The element 56 is normally visible. The ray exit window 2 is brought to the front by a rotation of 180 °.

Four building blocks according to Figure 1 are combined in Figure 10 to form a solar bar. They are mounted side by side between side walls 58 so as to form a wall and covered by a roof 59. Four bar stools 61 are fixed on the corresponding floor 60 at a distance such that a person seated on a stool, or leaning on it is at the correct irradiation distance.

FIGS. 11 and 12 represent an irradiation tower 62 with four cabins 63. Each cabin consists of two boxes 1 perpendicular to one another and limited by a folding external door or a curtain 64. The whole is interposed between a base plate 65 and a roof 66. A person in the cabin 63 is simultaneously irradiated from two sides. FIG. 13 represents building blocks with a fixed filter screen 9 put in place with a slight inclination relative to the horizontal, the window 2 for exit from the spokes being at the top.

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Irradiation trays 67 of this kind can be incorporated in isolation, or as shown, several side by side, permanently or detachably.

FIG. 14 represents a building block comprising a frame 68 fixed permanently to a wall of a room above a relaxation device 69. The window 2 for the exit of the spokes is placed obliquely at the bottom, so that the relaxation chair 69 is conveniently accessible from the free side.

The embodiment of FIG. 15 comprises a lower ultraviolet radiation emitter A, as well as another upper UV radiation emitter B. These two radiation emitters each form a building block with a housing 1 made of sheet metal, which contains several 3 ultraviolet sources 180 cm long and their associated reflectors 4 ·

The lower UV emitter A rests on a support frame 70 and the assembly forms a relaxation tray. To fix the upper ultraviolet radiation emitter B, two lateral brackets 71 fixed to the wall and which are housed in two support sheets 72 are used, an axis 73 around which the upper UV radiation emitter B pivots. This emitter can be locked in various angular positions, in particular in the operating position shown. The distance a. between the two emitters A and B of UV radiation is, as a rule, 40 to 60 cm.

In the embodiment of FIG. 16, the device has the shape of a barrel 74 and rests on feet 75. The relaxation tray is again formed by the lower UV emitter A. The emitter of upper UV radiation B forms the upper part of the inner wall of the barrel. The two lateral regions of this internal wall are occupied by two lateral UV emitters C. The various emitters of UV radiation, are constituted by lamps 3 with associated reflector, covered by narrow strips of glass 76 which, in the case of emitters B and C of UV radiation are joined in such a way that they form a part a cylinder whose cross section is advantageously elliptical in shape, but which can also be circular or approximately circular. Therefore, a person on the relaxation tray is irradiated from all four sides at once.

FIG. 17 represents an apparatus 101 for ultraviolet irradiation which comprises a tubular source of UV radiation, a reflector 103 in the form of a gutter, an intermediate screen 104, a filter screen 105 in the window 106 for exit of the rays and an outer casing 107 · The reflector 103 consists of two symmetrical halves which. form in the middle an angle 108 facing forward. The reflector 103 is formed, in the middle part 109 shown in bold line, by an ultraviolet reflecting glass and in the parts in thin line 110, by a normal reflecting material. The screen 104 is also reflective and is made, in a similar manner to the reflector 103, of two curved symmetrical halves, which form an angle between them in the middle. The gap between the reflector 103 and the housing 107 forms a cooling zone 111 in which a fan 112 circulates cooling air.

Assume that the source 102 of UV radiation is a xenon lamp. As indicated by curve V in FIG. 4, the xenon lamp emits, in the UV region, mainly UV radiation (A) but at the same time emits abundant light and heat radiation. The middle part 109 of the reflector is made in such a way that it practically only reflects UV radiation 113 and on the other hand allows light and heat radiation 114 to pass. Consequently, the undesirable light and heat radiation penetrates into the cooling zone 111 and is transformed when it falls on the wall 107 of the housing into thermal energy evacuated by the stream of cooling air. The UV radiation 113 passes through the filter screen 105, which filters out the majority of UV (B) and UV (C) radiation, so that practically only the UV radiation (A) 115 passes outside. The reflector is produced in such a way that the radiation emitted by the rear face of the xenon lamp passes, after one or two reflections, over the reflector 103 through the outlet window 106. The screen 104 not only prevents annoying heat and light radiation being directed directly at the user at the front, but also it guarantees that all of the radiation which reaches the reflector 103 directly falls on the middle section 109 of the reflection filter. By making the screen 104 in the form of a second reflector, it is furthermore made that the radiation directed towards the front is also reflected by a reflection on the median section, the reflection filter 109 and then, possibly after another reflection. , is directed outwards through the exit window 106, as indicated by the radius 116. One therefore obtains, in front of the exit window 106, a large area field having a relatively high UV radiation density (A), but nevertheless having only a low density, non-harmful, of light radiation, heat , UV (B) and UV (C).

The invention can be modified in several ways. For example, the building blocks shown in Figures 8 to 15 can also be fitted with high-pressure mercury lamps or xenon lamps as described in Figures 5 and 6, or 7 and 8. These blocks can also be incorporated into a niche in a wall. The building blocks can also be produced in the form of a corner console, for example, and have on their front face a folding cover mirror. In the case of fully automatic operation, the filter stopping UV (B) and UV (C) radiation can be folded up for a short time and then inserted again. It is also possible to directly make the glass envelope of the lamp in a filter material of this type ·

Insofar as the high density of UV radiation (A) still causes positive biological effects other than tanning, the irradiation device described can still be used to produce them.

It has been found to be advantageous, in practical embodiments, that the field of high density of UV radiation (A) is at a distance of 0 to 30 cm from the ray exit opening, the range of 10 to 20 cm. being however advantageous. In this do2 maine, a density of UV radiation (A) of at least 4 mW / cm,

2 preferably 5 to 30 mW / cm and, in particular approximately 15 mW / cm, is recommended. The extent of the field is, for a table-top device, preferably about 0.2 m. It should reach, for a device intended to irradiate the whole body, at least 0.5 m and have, for example, a width of at least 50 cm and a length of at least 120 cm.

The lamps described above exist commercially.

We can for example consider the following lamps:

Low pressure mercury lamps: Philips TL05 or TL09.

High pressure mercury lamps: Süddeutsche Metallwerke PQ 2000 Xenon lamps: Philips XOP 25.