Patent Publication Number: US-2007107121-A1

Title: Tanning booth

Description:
This invention relates to a booth in which a person may have a product such as a cosmetic product applied to her skin. The invention relates particularly to a tanning booth in which a person positioned within the booth may have a sunless tanning lotion applied to her skin.  
      Recently, public awareness of the harmful side effects of the sun&#39;s rays has become higher. It is well known that too much exposure to the sun can lead to skin cancer. Because of this risk, the popularity of cosmetic products which provide a “sunless” tan has increased significantly over recent years.  
      Existing sunless tanning lotions are often in the form of creams or lotions that may be self applied to the skin. A problem with such creams and lotions is that it is very difficult to ensure an even tan since the tan often is not visible until sometime after the cream or lotion has been applied to the skin.  
      It is also known to have such creams and products applied by a beautician. An advantage of this method is that a more even tan is usually achieved.  
      More recently it has been known to apply a sunless tanning lotion to the skin of a person with an air brush. This known method involves a beautician or other operator applying a sunless tanning lotion to a client using an air brush to spray the sunless tanning product over the skin of the client to achieve an even coverage over the skin.  
      A problem with this existing method is that although tanning products are not harmful when inhaled by beauticians applying the product to clients, beauticians may be exposed over significant periods of time to particles of sunless tanning lotion which may “hang” in the atmosphere during and after the air brushing process. In addition, a client to which the product is applied is often surrounded by a mist of the tanning product during and after the spraying process and so may inhale a significant quantity of the product during the tanning process. This can cause discomfort.  
      A tanning booth is described in our co-pending International patent application of even date, the contents of which are incorporated herein by reference.  
      According to a first aspect of the present invention there is provided a booth for accommodating a person, the booth defining a booth volume and comprising: 
          a base portion and a top portion;     flow means for causing a downward air flow within the booth;     projecting means for projecting a product into at least some of the booth volume within the booth and, in use, onto a body of a person positioned in the booth; and     control means for controlling the projection of the product.        

      The booth is adapted to accommodate a person requiring a product to be applied to her skin. The downward air flow within the booth means that the product projected within the booth and therefore onto the body of a person positioned within the booth is carried downwards in the air flow. This means that fewer particles of the product remain in the atmosphere and therefore fewer particles will be inhaled by the person receiving the tan.  
      Because the booth according to the first aspect of the invention comprises control means for controlling the projection of the product, it is not necessary for an operator to administer the product, or control the projection means. This reduces, or eliminates an operator&#39;s exposure to the product.  
      Advantageously, the control means controls the projection of the product according to parameters of the body of the person positioned in the booth.  
      People using a booth according to the invention will fall within a range of heights. In general, therefore, the booth of the invention is adapted to accommodate a body having a height of up to 6′ 4″ (1.94 m) and down to a minimum of 0.85 m. Theoretically there is not a minimum height, although practicably one cannot spray a person if her height is zero. Preferably, however a minimum height of 850 mm is created in order that if the sensor has not picked up anything by this height, it indicates to the system that there has been a malfunction in the sensing operation and therefore causes the system to reset.  
      In prior art booths, the amount of product projected onto a body within the booth would be the same regardless of the height of the body standing in the booth at any given time. This means that, in order to ensure that sufficient product is projected onto a person of maximum height, all people using the booth will have a maximum amount of product projected onto them. Because prior art booths are designed to cater for the largest body size which can be handled, consumption of the product is correspondingly unnecessarily high.  
      By means of the present invention, because the projection of the product is controlled in accordance with parameters of the body in the booth, product consumption can be tailored to suit each person&#39;s height thus reducing or eliminating wastage of product on shorter clients.  
      Advantageously, the control means comprises a sensor for sensing a parameter of the body. Preferably, the sensor senses the height of the body.  
      Although all human bodies are broadly of the similar shape, each body displays a set of unique nuances in shape and size. As mentioned herein above, this can cause problems with the automating spraying or projecting of a product onto a human body.  
      By means of the sensor therefore, relevant data from a body accommodated in the booth can be gathered. The data can then be used by the control means to vary the projection of the product to accommodate features of the body accommodated within the booth.  
      The projection of the product can be varied in accordance with the exact size and shape of each human body accommodated in the booth. However, a control means adapted to respond in this way to each different body accommodated in the booth would be time consuming to develop and therefore expensive.  
      The inventors have realised that in respect of the present invention, the most important parameter of a human body is the height of that body. Little if any further parameters are required in order to obtain sufficient data for the control means to effectively control the projection of the product. Other features of the body can be deduced by calculating the position of these features based on a percentage of the body&#39;s height. These percentages are based on mean averages of data taken from a large number of bodies.  
      For example, by means of the present invention it is possible to produce an approximate location of a client&#39;s ears. It is generally a problem with known booths that the rear of a client&#39;s ears is unnecessarily coated with product, causing inconvenience and a lack of realism in the resultant tan.  
      By means of the present invention, it is possible to prevent product from being sprayed onto the back of a client&#39;s ears thus resulting a more realistic tan.  
      The booth may comprises a plurality of sensors. Further sensors could be used to, for example, determine the width of a body standing in the booth in order to take into account bodies that have a larger body circumference i.e, bodies that are larger in terms of weight.  
      The sensor may be any suitable type of sensor, but preferably the sensor comprises an infra-red sensor.  
      Advantageously, the booth further comprises movement means for effecting movement of the projecting means.  
      Preferably, operation of the projection means is controlled by the control means.  
      Advantageously, the movement means effects vertical movement of the projecting means. This means that the height from which the product is projected may be varied both throughout the tanning operation, and also in response to the parameters of the body accommodated in the booth.  
      Advantageously, the movement means comprises at least one slider unit moveable vertically between two positions, the slider unit supporting the projecting means.  
      Preferably, the projecting means comprises at least one nozzle adapted to project the product.  
      Preferably, the projecting means comprises a plurality of nozzles each adapted to project the product. Through use of a plurality of nozzles, the product may be projected into at least some of the booth volume, and, in use onto a body of a person from a plurality of different projection points.  
      Advantageously, the booth further comprises adjustment means for adjusting the attitude of the nozzles. The adjustment means may be adapted to either adjust the attitude of the nozzles independently from one another, or to adjust the attitude of the nozzles so that all nozzles have the same attitude.  
      Advantageously, operation of the adjustment means is controlled by the control means.  
      Preferably, the projection means comprises a nozzle support defining a substantially arcuate shape, the nozzle being positioned to spray the product into an area defined by the nozzle support.  
      By means of the arcuate nozzle support, the product may be projected towards the centre of the booth into an area, where in use, a person will be accommodated.  
      The nozzle support may define a substantially circular shape or alternatively may define a semi-circular or other part-circular shape.  
      Preferably, the projecting means comprises one or more spray guns which are directed to spray product horizontally and/or at an angle to the horizontal (whether upwardly or downwardly, and/or some combination of these).  
      Alternatively, there is provided one or more slider units supporting an arcuate spray arm comprising a plurality of spray guns.  
      Advantageously, the booth further comprises a fluid delivery system for delivering the product into the booth via the projecting means.  
      Preferably, the fluid delivery system forms part of a recirculating fluid circuit which further includes the projecting means. The projecting means are thus able to be fed with fluid within the fluid delivery system. Any excess fluid that is not dispensed by the projecting means is returned to the fluid delivery system.  
      Advantageously, fluid is contained within a fluid container, and product which is not dispensed by the projecting means is returned by means of one or more pipes to the fluid container.  
      In order to project the product as a spray, the fluid delivery system delivers the product in liquid form, and also delivers air to the projection means for mixing with the product to form the spray.  
      Conveniently, the fluid delivery system delivers air to the projection means at a predetermined air pressure. Advantageously, the air pressure is varied. The air pressure is one of the factors that will contribute to the quality of the resulting tan.  
      Preferably, the fluid delivery system delivers product to the projection means at a fluid pressure.  
      Advantageously, the booth further comprises pressure means for controlling the fluid pressure.  
      Preferably, the pressure means comprises a fluid pump.  
      Conveniently, the fluid delivery system delivers product in form of a fluid to the projection means at a predetermined pressure.  
      Advantageously, the fluid pressure is varied. The fluid pressure will govern how much product is dispensed per second into the booth.  
      The pressure within the fluid delivery system is controlled by controlling how much resistance there is to movement of the fluid back into the container from which is it drawn—i.e. controlling the backpressure within the fluid circuit.  
      When the projecting means are operating at a particular setting, they will allow more or less product to be dispensed in direct relation to the pressure of the fluid that is feeding them. Less pressure in the fluid delivery circuit means that at the particular setting, the projecting means will dispense less fluid per second than if the fluid pressure is increased within the fluid delivery system.  
      Air and product are mixed together within the fluid delivery system to produce an atomising air stream so that the product is projected from the projecting means in an atomised form contained within an air stream.  
      Preferably the projecting means comprises a gun. The gun may create a conical spray pattern when projecting product into the booth, but preferably, the gun creates a pattern which is wider in one plane than another. Such a gun is known as a fan gun.  
      Advantageously, the spray pattern is wide in a substantially horizontal plane, and narrow in a substantially vertical plane.  
      The pressure at which the atomising air stream exits the projecting means, which is known as the atomising air pressure, causes differences in the way that the product is sprayed into the booth. If the atomising air pressure is raised, the product will be spread into a wider spray pattern in the horizontal plane, will project further, and the product will be atomised into finer particles.  
      When the product comprises a sunless tanning product, the depth of the tan may be controlled by controlling the pressure of the product in the fluid delivery system.  
      By controlling the pressure within the fluid delivery system to the projecting means, together with the speed at which the projection means move, the amount of the product dispensed per second, and the distribution of the product dispensed can be controlled.  
      Further, by controlling the air speed of the downward air flow within the booth, further control of fluid projection may be achieved.  
      Preferably, the booth further comprises recirculating means for recirculating the air within the booth. The recirculating means comprises any suitable air moving device such as a fan.  
      Advantageously, the booth further comprises a filter. The filter filters out particles of the product circulating within the booth.  
      Preferably, the booth comprises a plurality of filters forming a filtration system.  
      The booth may be used to apply a cosmetic product to the skin of the user. The cosmetic product could be any of a range of products such as skin moisturisers, but preferably the cosmetic product is a sunless tanning product.  
      Advantageously, the flow means comprises a first plenum of positive pressure located in the top portion of the booth, and a second plenum of negative pressure that is located in the base portion of the booth. The first and second plenums therefore result in the downward flow of air from the first plenum towards the second plenum.  
      The downward airflow may be arranged to occupy a predetermined volume within the booth. A person occupying the booth may stand in this predetermined volume during and after the tanning process.  
      Advantageously, the predetermined volume comprises a portion only of the booth volume.  
      This means that, for example, a client may leave personal belongings in a portion of the booth situated outside of the predetermined volume, which belongings will therefore not be exposed to the particles of sunless tanning lotion.  
      The recirculating means is used to maintain the pressure differential between the first and second plenums and therefore contributes to the down flow of air within the booth.  
      Conveniently the first plenum pressurises air in excess of the ambient atmospheric pressure and the second plenum depressurises air to less than the ambient atmospheric pressure.  
      Advantageously the first and second plenums are connected to a duct in which the air recirculating means is located. The first and second plenums, the duct, the recirculating means and the booth volume together form an air management system.  
      Preferably the booth further comprises temperature means for controlling the temperature of air circulating within the booth. The temperature means may comprise a heater which heats the air or alternatively may comprise a cooler which cools the air.  
      The temperature means may maintain the air within the booth at approximately 29° C. to 30° C. Preferably, however, the temperature means maintains the air within the booth at 33° C.  
      According to a second aspect of the present invention, there is provided a control system for a booth having projecting means for projecting a product into a booth volume within the booth, the control system comprising operating means to operate the projecting means in selected regions of the booth volume.  
      Preferably, the control system operates the projecting means to project specified amounts of the product in selected regions of the booth volume, the specified amounts varying from zero to maximum flow of the product from the projecting means.  
      Preferably, the projecting means is movable along a path within the booth and the control system operates the projecting means as it moves along the path in accordance with predetermined instructions.  
      There is also provided a method of controlling operation of a booth having projecting means for projecting a product into a booth volume within the booth, the method comprising operating the projecting means in selected regions of the booth volume.  
      There is also provided a computer program product directly loadable into the internal memory of a digital computer, comprising software code portions for performing the steps of the method when said product is run on a computer.  
      Preferably, the projecting means comprises a remotely operated tool.  
      According to a further aspect of the present invention there is provided a tool for projecting a product into a booth, the booth comprising a base portion and a top portion, flow means for causing a downward air flow within the booth, and control means for controlling the projection of the product.  
      In a preferred embodiment of the present invention, the projecting means comprises movement means to automatically move the tool to provide spraying between two zones in the booth. Preferably, the two zones comprise substantially the entire height of the booth.  
      The spray guns may be directed to spray product horizontally and/or at an angle to the horizontal (whether upwardly or downwardly) and/or some combination of these.  
      According to a further aspect of the present invention there is provided a method of applying a product to a human body using a booth, the booth defining a booth volume and comprising: 
          a base portion and a top portion;     flow means for causing a downward air flow within the booth; and     projecting means for projecting a product into at least some of the booth volume within the booth and, in use, onto a body of a person positioned in the booth, and control means for controlling the projection of the product. 
 
 defining a booth volume and comprising the steps of: 
    sensing the height of a human body accommodated in the booth;     estimating one or more other parameters of the body based on the height;     projecting a product into the booth and therefore onto the body;     controlling the projection of product into predetermined zones in the booth in accordance with the height of the body.        

      Preferably the step of projecting a product into the booth comprises spraying the product via the projecting means into the booth.  
      Advantageously, the booth comprises a fluid delivery system for delivering air and product to the projection means.  
      Preferably, the step of controlling the projection of product into predetermined zones within the booth in accordance with the height of the body, comprises one or more of the following steps: 
          controlling the pressure at which product is delivered to the projecting means;     controlling the pressure at which air is delivered to the projecting means.        

      Preferably, the step of controlling the projection of product projected into predetermined zones further comprises the step of causing the projecting lo means to move vertically within the booth, and controlling the speed at which the projecting means move.  
      Advantageously, the step of controlling the projection of the product further comprises the step of controlling the air speed of the downward air flow within the booth.  
      By means of the present invention, it is possible to direct the product to a predetermined point within the booth, and therefore to a predetermined part of a body standing in the booth. It is also possible to calculate accurately the amount of product required for different parts of the body.  
      By means of the present invention, therefore, because the control means is able to sense the height of a body standing in the booth, and then to determine where other parts of the body are located relative to the base of the booth, the amount of product projected by the projecting means can be varied in order to ensure that appropriate amounts of product are directed to predetermined parts of the body, in an appropriate manner.  
      By means of the present invention, therefore, the way in which a product is applied to a person within a booth according to the present invention involves control of some or all of the following parameters: 
          air pressure to the projecting means;     atomising air pressure to the projecting means;     speed of movement of the projecting means within the booth;     fluid pressure to the projecting means; and     air speed of the downward air flow.        

      Although the present invention has been described in terms of a booth, it would be possible to carry out the invention in an open environment. Similarly, it would be possible to carry out the invention within an area defined by the downward flow of air, which downward flow of air would ensure containment of the product within a predetermined volume. 
    
    
      The invention will now be further described by way of example only with reference to the accompanying drawings in which;  
       FIG. 1  is a schematic representation of a booth according to a first aspect of the present invention;  
       FIG. 2  is cross-sectional representation of the booth of  FIG. 1 ;  
       FIG. 3   a  is a schematic representation of the booth of  FIG. 1  showing product being projected onto a person standing in the booth having a predetermined fluid projection distance;  
       FIG. 3   b  &amp;  FIG. 3   c  are schematic representations showing product being projected onto the person in the booth of  FIG. 1  having increasing fluid projection distances;  
       FIG. 4  is a schematic representation showing how bodies of different heights may be accommodated within the booth;  
       FIG. 5  is a schematic representation showing how a predetermined amount of product may be projected into a predetermined zone of the booth, thus, in use, applying more product to certain parts of the body in the booth;  
       FIG. 6   a  and  6   b  are schematic representations showing the different positions taken by a body within the booth;  
       FIG. 7  is a perspective part view of a slider unit forming part of the booth of  FIG. 1 ;  
       FIG. 8  is a schematic representation showing in detail how a booth according to the invention would be operated; and  
       FIG. 9  is a block diagram showing the components of a booth according to the present invention; and  
       FIG. 10  is a flow chart of one way of applying product to a person using a booth according to the invention. 
    
    
      Referring to the figures, a booth according to the first aspect of the present invention is designated generally by the reference numeral  2 . The booth defines a booth volume also known as a spray chamber  4  and comprises a base portion  6  and top portion  8 . The booth  2  comprises an upper plenum  10 , and a lower plenum  12 . The upper plenum has a positive pressure with respect to atmospheric pressure, and the lower plenum has a negative pressure with respect to atmospheric pressure. This pressure difference causes a downward flow of air, in the direction of arrows  14 , of air circulating within the booth  2 . The booth  2  further comprises a duct  16  comprising an air mover  18  in the form of, for example, a fan (see  FIG. 2 ). The air mover  18  positioned in the duct  16  allows air to be recycled within the booth  2 . The booth further comprises a filtration system  20 , the purpose of which will be described further herein below.  
      The booth  2  further comprises projection means  22  comprising a spray ring  24  on which are mounted a plurality of spray guns, or nozzles  26 . The spray ring  24  is mounted on a slide carriage  28  which allows vertical movement of the spray ring. The booth  2  further comprises a range sensor  30  mounted on the spray ring  24 . The range sensor is used to detect the height of a person or client  32  standing the booth as will be described in more detail herein below.  
      The booth further comprises doors  34  which are moveable between a sealed positioned as shown by the solid lines in  FIG. 2 , and an open position as shown by the broken lines in  FIG. 2 .  
      The spray ring  24  on which the spray guns  26  are mounted, enables the guns  26  to be mounted in precise predetermined positions.  
      The spray ring is in turn mounted on the slide carriage  28 . The slide carriage  28  enables the spray ring to reciprocate from the top of the spray chamber  4  to the bottom of the spray chamber. This enables the guns  26  mounted on the spray ring to be moveable along a predetermined distance, for example, along the entire length of a client  32  having a maximum height of, for example, 6′ 4″. The slide carriage  28  is caused to reciprocate by way of an electrical motor (not shown) and is driven via any suitable drive shaft mechanism.  
      The spray guns deliver product into the spray chamber and cause the product to be atomised on entry into the spray chamber.  
      During the act of spraying, the tanning product becomes air borne in the form of small droplets. The downward airflow of the present invention ensures that these small droplets are kept away from the client&#39;s face and that a clean supply of air for the client is available. The filtration system  20  serves to filter out particles of the product to ensure that the recirculating air is as clean as possible.  
      In other words, although a client&#39;s face is sprayed with product, the face is exposed to excess product only from the time that the projecting means are above the face, or pointing directly on it. Due to the height sensor forming part of the present invention, this time period is approximately the same for each client, thus creating a safer system from the inhalation point of view.  
      Typically, the time that a client will have excess spray particulate in the vicinity of their face will not exceed approximately 2 seconds for each pass of the slide carriage. In addition, because of the downward air flow within the booth, any excess product is drawn away from a client&#39;s face. Further, when the rear of a person is being sprayed, in order to avoid excess coating of the rear of the ears of a client, the projection means begins spraying at a point which is lower in height than the corresponding point when the front of the body of the client is sprayed. This means that exposure in the head area of a client when the rear of their body is being sprayed is typically less than 1 second.  
      A percentage of the air flow is bled off from the first plenum  10  in order that the differential between the air volume being drawn from the booth volume  4  into the second plenum and the air volume being moved into the booth volume  4  from the first plenum  10  is replaced by air movement into the downward flow of air within the booth volume. This management of the air flow prevents any outward flow of particles from the booth volume  4  during the spraying process and ensures that all particles generated within the booth volume  4  must pass through the filtration system  20  thus ensuring that the client is maintained in clean air.  
      The filtration system  20  filters substantially all wet and dry particulate material from the recirculating air.  
      A downward flow of air is the most efficient way to move air over a human body as moving air downwards over a body ensures that the body presents a minimum cross sectional area of impedance to the air flow.  
      The downward air flow capitalises on the tendency for heavy atomised particles to drop downwards under the influence of gravity. The downward airflow thus uses gravity to assist in the process of extracting particles generated by the spraying tool from the booth volume  4 .  
      Since air is recycled within the booth  2 , it will not be necessary for a purchaser of the booth  2  to carry out building work to their premises in order to create ductwork to the atmosphere. By using a recirculating air stream there is no need for any building work to be carried out since no ductwork to the atmosphere is required.  
      The booth  2  further comprises a heater  34  which warms the air in the downward airflow. The combination of spraying a wet product onto a client&#39;s skin in conjunction with an air stream moving over the body of a client creates a “chill factor”. By means of the heater  26  it is possible to ensure that air passing over the body of a client is at an appropriate temperature. Further, after the spraying process has been completed, a client may be dried by the airflow.  
      Although the invention as hitherto been described with reference to a heating apparatus for heating the air flowing through the booth, it is envisaged that in warmer climates or during the summer of temperate climates it may be advantageous to cool the air flow.  
      The fan  18  causes the air within the recirculated down draught extract system (indicated by arrows  14  in  FIG. 1 ) to be moved within the booth. The speed at which the fan is caused to run influences how much air volume is moved through the fixed volume of the air management system, therefore influencing the speed of the air moving downward within the spray chamber.  
      The range sensor  30  is able to detect the position of features on the client&#39;s body such as the top of the head of the client&#39;s body. The sensor works by “seeing” only within a certain range. In the present embodiment the range of the sensor is 700 mm. It will sense anything within this range. At this range the sensor will sense only what is actually inside the spray chamber and not, for example, the inside of the doors should they be closed. A client stands within the range of the sensor when inside the spray chamber thus enabling the range sensor to detect the top of the client&#39;s head.  
      The booth  2  further comprises filtered constant bleed sites  36  for ensuring that the pressure does not build up within the booth. These bleed sites ensure that the pressure differentials within the two plenums obey the following rule in order to ensure that there is no possibility of atomised product leaving the spray chamber other than through the filtration system:
 
Overpressure in upper chamber—one atmosphere=X
 
Underpressure in lower chamber—one atmosphere=Y
 
      With the effect of the bleed sites, Y is always greater than X thus causing an IN-flow of air through any leak sites within the spray chamber itself, thus ensuring that no atomised product can leave the spray chamber other than via the filter systems.  
      The booth  2  further comprises a control system  90  which can take any suitable form, but in this embodiment comprises electrical and electronic components which are run by real time embedded software. The control system controls the general operation of the booth  2 , and all of the variable parameters within the system. The control system is able to self-teach. This means that once the sensor has sensed the height of a person standing in the booth  2 , the control system is able to work out the necessary parameters for controlling projection of product into the booth  2 . The control system is able to work out how to appropriately control the projection of product into the booth by initially working out where different parts of the body are located relative to the base of the booth, based on the known proportions of an average human body. The control system is then able to work out variables such as the speed of the fan, speed of movement of the spray ring along the slide carriage  28 , and timings for switching on and off the spray guns in order to apply product appropriately to the person standing in the booth. The control system is also able to calculate the points at which the air and fluid pressure are varied to the guns, and the points at which the fan speed alters, where the gun carriage accelerates and slows down, as well as where it moves from and to. For each cycle of the booth, these parameters are calculated again, and in this embodiment are not stored in the memory within the control system.  
      In some embodiments of the invention, it is also possible to increase or decrease the fluid pressure to the guns. This results in a client being given a darker or lighter tan depending on the fluid pressure to the guns.  
      The type of tan required could be selected by a particular client, each time that client enters the booth. However, in certain embodiments of the invention, in order to cut down on the information that a client has to input into the booth on entry to the booth, information relating to the preferences of a particular client could be stored on magnetic media, such as a credit card type strip. This means that a client may simply walk into a booth and swipe their settings into the booth, so that they generate their last profile parameter set which includes the preferred depth of tan setting in the most convenient way possible.  
      The particular settings calculated by the control system  90  are known as a profile parameter set.  
      In use, a person requiring product such as a self-tanning product to be applied to her skin, enters the booth  2 . Once the client  32  is within the booth, the doors  34  are closed in order to create a sealed environment. The client  32  is instructed, for the sake of simplicity, to place her feet on fixed plates  36  located on the floor of the booth  2 . This ensures that the client is standing in a repeatable position during the operation of the booth. Once the client is in position, the range sensor  30  senses the height of the top of the client&#39;s head. Once the height of the fop of the client&#39;s head has been sensed, all other relevant points on the client&#39;s body can be deduced with sufficient precision by calculating the position of these parts of the body as percentages of the client&#39;s height. These percentages are based on mean averages of data taken from a large number of individuals. The sensor  30  detects the height of the client by reciprocating from the top of the spray chamber towards the bottom along the slide carriage  28 . It is not necessary for the sensor to reciprocate along the entire length inside the spray chamber. It is necessary only for the sensor to reciprocate downward until a signal is emitted from the sensor when it determines the presence of the top of the client&#39;s head. Once this information has been gathered, the slide carriage  28  returns the spray ring to the position which is appropriate to start the profile parameter set for which it has just gathered the information. All profile parameter sets start at a fixed dimension over the client&#39;s head. For example should the client be 1700 mm tall then the slide will proceed downward from the “home” position in which if rests (the uppermost reach of its stroke) until the signal is gained from the sensor i.e. at 1700 mm. It will then slow down and stop in a controlled manner, whereupon it will reciprocate upwards to the first point in the profile parameter set created for that client. The profile parameter sets start the spraying operation 50 mm above the top of the client&#39;s head. Therefore in this case, the slide would return upward to a point which places the gun nozzles at a height of 1750 mm. This is the point at which this particular profile parameter set would cause the application of product to be started. However, if the sensor or sensors are used in a more detailed manner i.e. to sense further information regarding the client&#39;s body, the slide carriage  28  may be required to reciprocate the slide all the way to the bottom of the spray chamber.  
      Once the height of the client has been determined, the profile parameter set is created. This is a set of instructions issued by the control system to the components of the spray booth system in order to achieve application of the product as dictated by the information gathered and processed. Once the profile parameter sets have been created, the projection means are able to project product into predetermined zones within the booth so that the application of product onto the client is optimised.  
      Other information which is deducible from the height of the client is the approximate position of the upper and lower body, divided at the hip line.  
      This enables the system to be able to carry out partial body tans correctly sized to the client&#39;s body. Clearly a 6′ tall person would have a hip line in a very different position relative to the base of the booth than a 5′ tall person. By means of the present invention it is possible to offer partial body tans, either upper or lower, to clients since it is possible to determine where the hip line of a particular client is relative to the base of the booth.  
      The depth of the tan produced by application of the product to the person standing the booth can be controlled by controlling the pressure that the tanning product is delivered to the projection means via the fluid delivery system.  
      It is therefore, possible for a client to select a “tan depth”.  
      The applicant has become aware that different skin types absorb product differently.  
      Generally speaking, fair skin types will absorb product more slowly, and to a lesser extent in any one application.  
      A preferred treatment cycle therefore, comprises two cycles of treatment during which 55% of the normal dosage of product is delivered to a person standing in the booth, each cycle being punctuated by a one minute pause. The pause allows the skin to absorb the product. This absorption process is assisted by the downward air flow within the booth which is generally heated to a temperature of approximately 29-30° C. After the second cycle, there is two minute drying period. A flow chart showing such a cycle is illustrated in  FIG. 10 .  
      For all skin types, a very dark tan can be achieved using a twin cycle, with up to 100% of the normal dosage being delivered in each cycle.  
      However, it has been found that it is preferable to deliver 75% of the normal dosage in each of the two cycles. This will result in a client having 150% of the normal dose applied to her body. However, by applying the product in two cycles, the skin is allowed to absorb the product between the two applications. This prevents wetting of the product on the skin of a client, and therefore also prevents potential streaking.  
      Of course it falls within the scope of the present application, that different types of cycles may be used to administer product to a particular person.  
      The control system controls the speed of the slide carriage  28 , the guns switching positions and the fan speed.  
      By controlling the speed of the slide carriage, the amount of product projected into predetermined zones in the booth and therefore deposited, particularly onto areas of the client&#39;s body, by the guns  26  is determined. The guns are preset to deliver a known quantity of product per second. Therefore, if the slide carriage moves more quickly through its reciprocating stroke, or part of its stroke, then the area of the body which is to be sprayed at that part of the stroke will receive less product. This is because the guns pass more quickly over a particular part of the body when the slide carriage is moving more quickly, and vice versa.  
      The positions within the stroke of the slide carriage at which the guns are switched on and off, i.e, the times at which they are spraying and not spraying are also controlled by the control system.  
      Controlling the speed of the fan  18  causes a greater or lesser volume of air to be moved per second through the finite volume of the booth  2 . Therefore if the fan speed is increased, a greater volume of air will be recirculated per second within the booth. This causes an increase in the speed of downward extracting airflow within the spray chamber. This in turn increases the airflow speed within the spray chamber and causes the fluid projection distance to be decreased (see  FIGS. 3   a ,  3   b  and  3   c ). By decreasing the fluid projection distance to an approximate equivalent to the distance between the client and the guns, it is possible to cause a greater deposition of product onto predetermined areas of the client, for example, onto the tops of the client&#39;s shoulders, therefore causing a higher degree of realism to the completed tan (see, for example,  FIG. 5 ). In addition, deposition of the product into difficult to reach areas such as the client&#39;s inner thighs can be enhanced by being able to increase the fluid projection distance at this point on the body.  
      Control of the fan speed can also be beneficial in dealing with a problem caused by the client facing one way and then the other. The client is instructed to stand first facing one way and then to turn through approximately 180° to stand in an opposite direction. However, when the client presents the rear of her lower leg to the spray ring (as shown in  FIGS. 6   a  and  6   b ), the lower leg is positioned closer to the spray ring than when she presents the front of her lower leg to the spray ring. This is due to the shape of the human foot, and where the lower leg intersects with the foot. By controlling the fluid projection it is possible to ensure that the coating is approximately identical on both the front lower leg and the back lower leg.  
      In an alternative embodiment, the spray ring is mounted for horizontal, as well as vertical movement. This means that the spray ring may be moved relative to the client in order to apply product to the back of the client. This obviates the need for the client to move through 180°.  
      In cases, where an operator of the booth will offer partial body tans to clients, it is commercially necessary to ensure that a client is not able to select a full body tan even though they have only paid for a partial body tan. In order to ensure that the client cannot select a full body tan when only paying for a partial body tan, the client can be issued with a small plug-in item. Within this item is an EPROM chip. This chip carries the necessary instruction to the control system to ensure that it carries out the relevant treatment. When inserted into the spray booth system, the EPROM chip carried in the device will ensure that the client will receive only the treatment that they have purchased. Once the plug in device is inserted, the control system will be alerted that the client is ready to proceed and will commence the body scan to determine the height of the client. If a client chooses to have a partial body tan, for example of her legs only, then the control system will calculate a position of the top of the client&#39;s legs and will begin the spraying process at this height.  
      Alternatively, data may be transmitted to the booth using radio frequency signals. This obviates the need to use an EPROM chip, which could be easily lost. An operator will select the treatment type purchased by the client at, for example, the front desk of the salon. A signal is then directed to the booth via a simple menu structure on the desk top controller. The booth sends a receipt signal to the controller upon receipt of its instructions, so that the operator knows that the booth has received the data and is ready to dispense the relevant treatment.  
      In this embodiment of the invention, the spray ring will continue to move along the entire stroke of the slide carriage, but the control system will activate the guns at the appropriate point to apply product to the legs only of the client.  
      However, in other embodiments, the spray ring may travel up to the appropriate point only and will not carry on to complete the entire stroke of the slide carriage.  
      Because the booth according to the present invention is able to detect the height of a client, the application of product is more efficient and there is less waste since an appropriate amount of product may be applied in accordance with the height of the client.  
      Further, in the case of shorter clients, the product will be sprayed at an appropriate height relative to the head of the client, which will reduce the possibility that the client will inhale the product. In prior art booths, where the height of the client cannot be taken into account, an unnecessarily long period of time may be spent on applying product to, and above, the client&#39;s face.  
      By means of the present invention, however, since it is possible to detect where the client&#39;s head is located, only sufficient product to apply the product to the face will be projected onto the face of the client, thus reducing the amount of product that the client could inhale.  
      Further, by means of the present invention, it is possible to apply different amounts of product to different parts of a client&#39;s body. The inventors have determined that certain areas of the body are capable of absorbing more product than others before excess application occurs. Excess application is undesirable as this causes the product to run off the skin leaving streaks in the finished application and therefore the tan. By being aware of the locations of various parts of the body that require differing amounts of product, and applying the product accordingly, the disadvantages of excess product application are minimised.  
      In prior art booths where it has not been possible to control the amount of product dispensed onto a person standing within the booth, the amount of product dispensed is limited by how much product can be absorbed by parts of the body that are less absorbent than others. This in turn limits the depth of the tan which can be produced by a sunless tanning product.  
      By means of the present invention, therefore, it is possible to maximise the amount of product applied to all body parts without the previously existing problems of over application.  
      With conventional booths used to apply sunless tanning product, if for example the amount of product applied to the body of a person standing in the booth was determined by the amount of product that could be absorbed by the calves of a person, then a light tan to the back would result.  
      By means of the present invention, it is possible to apply a maximum amount of product to each body part, by varying the amount of product applied to the different body parts.  
      It appears that an even sunless tan can be achieved, not from ensuring that the amount of product applied to a person&#39;s body is the same all over the body, but rather from ensuring that a maximum amount of product is applied to each particular body part, or a common percentage of this maximum amount is applied to all body parts. This results in an even tan being obtained, the strength which can be determined by the percentage of the maximum amount of product that is applied to particular body parts.  
      The resulting tan is more realistic because certain parts of the body, for example, the shoulders can be given a darker tan which is consistent with the appearance of a natural tan.  
      By means of the present invention therefore a highly specific and controlled delivery of atomised products such as a sunless tanning product may be applied to the client. There is no need for the client to manually manipulate the product once it has been applied to the skin in order to ensure even coverage.  
      There is shown in  FIG. 7  details of a spray ring  50  suitable for use in booth  2 .  
      The interior of booth  2  contains a slide unit  52  which supports a spray arm  54  to provide vertical upward and downward movement of arm  54  over the entire height of the booth. In other embodiments, there may be a plurality of slide units.  
      Spray arm  54  comprises a horizontal arcuate arm containing a plurality of spray guns  55  to direct tanning lotion inwardly and horizontally generally towards the centre of arm  54  and hence onto any occupant of the booth.  
      Thus, spray arm  54  can be shaped to form an arc of from 0° to 360° However, in this embodiment the arc as measured between the two outermost guns is 85°. The spray guns may extend along the entire periphery of the arm.  
      The spray guns are positioned so as to direct the lotion horizontally. In a variant, they may be positioned to direct the lotion at a small angle inclined to the horizontal. In another variant, the guns may be positioned to direct the lotion at various different angles either upwardly or downwardly, and either in a random manner or in an organised, progressively changing manner.  
      Spraying mechanism  50  also has a motor  57  and a gearbox  58  to provide the vertical motion of slide units  52 ,  53 .  
      The “open” configuration of spray arm  54 , has been developed with safety in mind. The spray arm  54  allows client access in from one side, regardless of the position within the spray chamber and it enables a quick exit in case emergency procedures need to be followed. It also allows for a quick exit if the client, for whatever reason, feels uncomfortable with the process. If movement of the spray arm  54  is halted at any position during its travel, the client is still able to exit the booth with minimal discomfort or danger.  
      In order to spray the client over the whole body using this design of spray arm  54 , the application of tanning lotion must be applied in two steps. In the first step the front section of the body is sprayed; the client then turns through 180 degrees, and actuates operation of the spray arm  54  again, thereby applying lotion to the rear section of the body. Multiple spray guns would only be seen on one section the spray arm.  
      Alternative designs may allow for pneumatically actuated slide systems, but they tend to lack precise speed control, acceleration and deceleration parameters as compared to the programmable, electrically driven slide system.  
      The drive system is based on a servo motor  56  arrangement, allowing for the programmable switching of the spray guns according to the different requirements of the client. Alternative drive solutions include stepper motor control, AC and DC stepper motors.  
      The spray ring  50  further comprises a flexible coupling  58  which connects the servo motor to the slide carriage  52 . The spray ring  50  also comprises an encoder for enabling the spray ring to be programmed by the control system.  
      The spray ring  50  further comprises a carriage home position sensor  60  which senses when the spray ring has reached its maximum height, and an over travel safety switch  61  which would cut off power to the spray ring in the event that it travelled beyond its maximum height.  
      In addition to the drive motor arrangement, the rate of rotation is reduced using a gearbox arrangement  57 . This provides a higher torque, which is required to overcome the weight of the spray arm  54  and actually allows for more precise positioning of the slide systems.  
      In order to keep the doors closed, a magnetic latch system is used. This allows the doors to stay closed against the spring-loaded “opening” system, but also allows for manual release of the doors should an emergency procedure arise, requiring the client to exit the booth. If a power cut experienced, the doors are automatically opened by default, immediately providing a clear exit for the client.  
      Alternatively, a mechanical latch may be used to close the doors.  
      Turning now to  FIG. 8 , the operation of a booth according to the present invention is described in more detail.  
      Set out below is process flow chart and sequence of operations describing the operation of the booth  2  with reference to  FIG. 8 .  
                 
                 
                 
 
      Turing now to  FIG. 9 , a block diagram showing the components of the booth  2  is illustrated. The booth  2  comprises a control system  90  which controls the various components forming the booth  2 . In particular, the booth  2  comprises a closed loop air heating system  92  and a spray chamber lighting system  94 . An AC inverter drive system  96  is used to power the fan  36 . Movement of the spray ring is controlled by the slide carriage servo motor  56  which in turn is controlled by a DC closed loop motion controller  98 . If an EPROM chip is use, then an EPROM tag management system  100  is also controlled by the control system  90 . The booth further comprises an internal LCD multi-media display  110  which allows the client positioned within the booth to see the settings of the booth  2 , and an external alpha numeric display  120  which allows an operator to monitor the spraying operation. The control system  90  is run in conjunction with a Windows (RTM) embedded PC system  130 .  
      In other embodiments, the LCD display  110  may be omitted. In such embodiments, there is no longer a requirement for a Windows (RTM) embedded PCT system  130 .