Field of the Invention

The present invention relates to medical equipment and particularly laser-based medical equipment.

Background of the Invention

Various laser-based systems are used in medical environments. One potential use of such systems relies on directing appropriate laser beams onto the skin of patients. Such systems have been proposed for use in altering, removing or ablating the stratum corneum so as to increase the permeability of the skin thereby providing a mechanism for administering a large variety of therapeutic and other substances. Such systems have also been proposed for use in blood collection.

Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is' solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.

Summary of the Invention

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

According to a first aspect, the present invention is a tip member for a laser emitting device, the tip member having an optical pathway having a first end, a second end, and extending through at least a portion of the tip member; wherein the pathway has at least one reducing means that reduces the diameter of a laser beam passing through the optical pathway that has a diameter greater than a predetermined size.

In one embodiment, the tip member, or one or more parts thereof, can be detachably mountable to the laser emitting device. In another embodiment, the tip member, or one or more parts thereof, can be integrally mounted to the laser emitting device. Still further, the tip member, or one or more parts thereof, can be non- detachably mountable to the laser emitting device.

In another embodiment, the reducing means comprises a component having one or more apertures that is placed in the optical pathway. While the component can have one aperture, where more than one aperture is provided in the optical pathway, the laser beam can pass through a first aperture and then a subsequent aperture and so on until the remaining portion of the laser beam exits the reducing means. Each subsequent aperture can have a smaller diameter than its preceding aperture. The component can be constructed such that any portion of a laser beam striking the component around the one or more apertures does not continue to travel through the optical pathway. Any portion passing through an aperture is free to continue at least past the component and further through the pathway. It will be appreciated that the laser beam entering the tip member may have a diameter less than a first aperture but greater than any second or subsequent aperture provided in the tip member.

In one embodiment, the component can comprise a tube having a first end, a second end, and at least an inner surface, this tube defining part of the optical pathway. In one embodiment, the inner surface of the tube can be of constant diameter along its length between its first end and second end. In another embodiment, the inner surface of the tube can undergo at least one change in diameter along its length. The inner surface of the tube can undergo two or more changes in diameter. In yet another embodiment, the inner surface of the tube can vary in diameter, at a constant or non- constant rate, along its length. For example, the inner surface can reduce in diameter along its length from the first end to the second end.

In a further embodiment, the diameter of the reducing means is set such that the portion of the laser beam passing through the reducing means has a relatively constant energy fluence or density across at least a portion of its diameter, more preferably at least a majority of its diameter, and still more preferably across the entire diameter. In one embodiment, the diameter of the aperture or tube can be greater than 3mm. In another embodiment, the diameter can be between 3mm and 8mm. In yet another

embodiment, the diameter can be about or exactly 6mm. The diameter of the laser beam can be reduced by passing through the tip member by between 10% and 70%, more preferably between 15% and 30%, still more preferably by about 25%. The laser beam can be diverging on entering the tip member. In another embodiment, the laser beam can be of constant diameter on entering the tip member.

In a still further embodiment, the one or more apertures can be circular in shape. Other suitable shapes can be envisaged including ovals, squares, triangles and other multi-sided shapes. Where more than one aperture is provided, the apertures can have the same shape or different shapes. Where a tube is provided, some or all of the tube can have a cylindrical inner surface. Again, tubes having inner surfaces of different cross-sectional shapes to circles can be envisaged including ovals, squares, triangles and other multi-sided shapes.

In a still further embodiment, a window can be provided across the aperture, in the tube, and/or at one or both of the ends of the tube. The window can be transparent to at least light transmitted at some or all optical wavelengths. The window can be constructed of a polymeric material or a glass. In another embodiment, a lens can be provided in addition to or instead of the window.

In a still further embodiment, the component can comprise an inner member and an outer member. The inner member can have an annular flange that can frictionally engage within the outer member. In this embodiment, the inner member can define the tube of the component described above. The outer member can have a first end and a second end with the second end defining a face surrounding another aperture therein. A tubular member can extend back from this another aperture for a distance towards the first end of the outer member. The inner diameter of this tubular member can be the same as the diameter of the inner surface of the tube of the inner member. In another embodiment, the inner diameter of the tubular member can be different, for example, larger or smaller, to the diameter of the inner surface of the tube of the inner member. Where it is smaller, it will be appreciated that the tubular member, such as its end distal the second end of the outer member, will act as an aperture and so further reduce the diameter of a laser beam that has entered the first end of the inner member or tube and which has a diameter greater than the diameter of the tubular member.

Still further, the inner surface of this tubular member can be constant or it can vary in diameter along its length.

A window, such as already described, can be held in the component between the inner and outer members. In one embodiment, the window can be held between the end of the tubular member extending back from the aperture in the face of the second end of the outer member and an end of the tube. The window can be held in place by a friction fit that exists between the tube and the outer member.

The face at the second end of the outer member can, in use, be contactable with the skin of a patient. Some or all of this face can support a site identifier means that, following contact between the skin and the surface, marks or modifies the surface of the skin thereby revealing where the tip member has been in contact with the skin. In one embodiment, the site identifier means can comprise a ring that is removably mountable to the face and transferable to the skin of the patient when applied thereto. The removable mounting of the ring can be provided by an adhesive layer. The outer surface of the ring can also be provided with an adhesive layer that facilitates adhesion of the ring to the skin of the patient on contact therewith. The respective adhesive layers can have a different degree of adhesion to thereby ensure transfer of the ring off the face of the outer member and onto the skin on contact with the skin. The ring can be annular and/or have one or more slits formed therein. An inner and/or outer end of the slit can be tapered or notched. Assuming the laser beam is applied to the skin of the patient, the annular ring left on the skin easily identifies the location of the skin that has received the laser beam.

In yet another embodiment, the tip member can have a main body having a first end and a second end. The first end of the optical pathway can be at the first end of the main body. Similarly, the second end of the optical pathway can be at the second end of the main body. The main body can have a portion that is engageable with the laser emitting device and another portion to which the reducing means is mounted or mountable. The reducing means can be detachably mountable to the tip member. These portions of the main body can be integrally formed in comprising the tip member. Said portion for receiving the reducing means can comprise a chamber. This chamber can also have a cylindrical inner surface having a dimension that allows the reducing means to be slidably supported therein. The chamber can also have an outer cylindrical surface.

In this and other embodiments, the component can move between a first position and at least one second position whilst still mounted to the tip member. The component can be in the first position prior to mounting to the laser emitting device and move to the second position on or following mounting to the laser emitting device.

Once in the second position, the component can be held by a retaining mechanism that prevents or substantially prevents further movement of the component. In one embodiment, the retaining mechanism can comprise a rim on the component that engages with one or more nodules disposed on the inner surface of the chamber of the tip member.

In a further embodiment, a cap member can be provided that is removably mountable over the chamber of the tip member. The cap member can be transparent. The cap member protects the face of the component from inadvertent contact prior to use.

Where the tip member is detachably mountable to the laser emitting device, the mounting of the tip member can control energizing and/or firing of the laser emitting device. For example, mounting of the tip member to the laser emitting device can trigger one or more switches that enable energizing, or energizing and firing, of the laser emitting device. One or more tabs or other member can be provided on the tip member to trigger said one or more switches. In this regard, energizing may be automatic once the switches are triggered. Alternatively, triggering of the switches may merely mean that energizing can now commence when another control device, such as a switch, button or trigger, is activated by the user of the laser emitting device.

The tip member can be designed to be used only once. For example, once mounted to the laser emitting device, and the laser emitting device has fired, the device can be set so as to not be refirable unless the tip member is removed and a new tip member is mounted thereon. In one embodiment, the tip member can be constructed such that once mounted and then removed from the laser emitting device, re-mounting of the same tip member does not trigger said one or more switches enabling energizing of the laser emitting device.

According to a second aspect, the present invention is a laser system comprising:

a laser emitting device having a laser element; and a tip member mountable to the laser emitting device, the tip member having an optical pathway having a first end, a second end, and extending through at least a portion of the tip member; wherein the pathway has at least one reducing means that reduces the diameter of a laser beam passing through the optical pathway that has a diameter greater than a predetermined size.

In this aspect, the tip member can have one or more of the features of the tip member as defined herein according to the first aspect of the invention.

In a further embodiment, the laser system can comprise a housing for at least the laser element.

In another embodiment, the laser system can further comprise at least one diverging lens that causes the emitted laser beam to be expanding in diameter after passing through the lens. In one embodiment, the laser beam diameter on entering the tip member and/or reaching the reducing means can be greater than 6mm. In this or other embodiments, the laser beam diameter, on exiting the tip member and/or passing through the reducing means, can be exactly or about 6mm.

In one embodiment, the diverging lens can be positioned within the housing.

In a further embodiment, the laser element can emit a pulsed beam. The laser element can be selected from the group consisting of Er.YAG, pulsed CO ₂ , Ho:YAG,

EnYAP, Er/Cr:YSGG, Ho:YSGG, EnGGSG, Er:YLF, Tm:YAG, Ho/Nd:YAlO ₃ , cobalt:MgF ₂ , HF chemical, DF chemical, carbon monoxide, deep UV laser, diode laser, and frequency tripled Nd: Y AG lasers, and all combinations thereof.

The laser beam can have a wavelength of between 0.2 and 10 microns. The wavelength can be between 2 and 7 microns and, in particular, between 2.9 and 3.0 microns. In one embodiment, the wavelength is 2.94 microns.

The laser beam can have an energy fluence of between 0.03 and 100,000 J/cm ² , more preferably between 0.03 and 9.6J/cm ² .

The laser beam can have a pulse width between 1 femtosecond and 1000 microseconds, more preferably between 1 and 1000 microseconds, still more preferably 400 to 600 microseconds and, in particular, about 200 microseconds.

The laser beam can create a site of alteration or ablation in the skin of the patient when the light beam is applied to the skin. The site of alteration or ablation can be circular or another shape, including slit-shaped. The site of alteration or ablation can have one or more therapeutic or other compounds subsequently applied thereto.

In a further embodiment of this aspect, the laser system can be a portable or hand-held device. The laser system can be powerable by one or more on-board power sources, including batteries, such as rechargeable batteries. In another embodiment, the system can be powered, in use, by mains power.

The system can further comprise:

- a high voltage pulse-forming network that receives power from the power source used by the system;

- a means for exciting the laser element linked to the pulse-forming network; and - a laser cavity.

According to a third aspect, the present invention is a tip member for a laser emitting device, the tip member having a body having a first end, a second end, and an optical pathway for a laser beam extending through at least a portion of the tip member; wherein the second end of the body is contactable with the skin of a patient and supports a site identifier means that, following contact between the skin and the surface, marks or modifies the surface of the skin thereby revealing where the tip member has been in contact with the skin.

In one embodiment of this third aspect, the second end can comprise a face. The site identifier means can comprise a ring that is removably mountable to the face and transferable to the skin of the patient when applied thereto. The removable mounting of the ring can be provided by an adhesive layer. The outer surface of the ring can also be provided with an adhesive layer that facilitates adhesion of the ring to the skin of the patient on contact therewith. The respective adhesive layers can have a different degree of adhesion to thereby ensure transfer of the ring off the face and onto the skin

on contact with the skin. The ring can be annular and/or have one or more slits formed therein. An inner and/or outer end of the slit can be tapered or notched. Assuming the laser beam is applied to the skin of the patient, the annular ring left on the skin easily identifies the location of the skin that has received the laser beam.

In this third aspect, the tip member can further comprise at least one reducing means that reduces the diameter of a laser beam passing through the optical pathway that has a diameter greater than a predetermined size.

In a further embodiment, the tip member of this third aspect can have one or more of the features of the tip member as defined herein according to the first aspect of the invention.

According to a fourth aspect, the present invention is a laser system comprising: a laser emitting device having a laser element; and a tip member mountable to the laser emitting device, the tip member having a body having a first end, a second end, and an optical pathway for a laser beam extending through at least a portion of the tip member; wherein the second end of the body is contactable with the skin of a patient and supports a site identifier means that, following contact between the skin and the surface, marks or modifies the surface of the skin thereby revealing where the tip member has been in contact with the skin.

In this aspect, the laser system can have one or more of the features of the laser system as defined herein according to the second aspect of the invention.

In this aspect, the tip member can have one or more of the features of the tip member as defined herein according to the third aspect of the invention.

According to a fifth aspect, the present invention is a laser system comprising: a laser emitting device comprising a housing; a laser element within the housing for emitting at least one laser beam; and a tip member mountable to the housing of the laser emitting device, the tip member having a body having a first end, a second end, and an optical pathway for the laser beam extending through at least a portion of the tip member;

wherein at least one diverging lens is provided in the housing that causes the emitted laser beam to be expanding in diameter after passing through the lens.

In this fifth aspect, the tip member can further comprise at least one reducing means that reduces the diameter of a laser beam passing through the optical pathway that has a diameter greater than a predetermined size.

In this fifth aspect, the laser beam diameter on entering the tip member and/or reaching the reducing means can be greater than 6mm. On exiting the tip member and/or passing through the reducing means, the laser beam diameter can be exactly or about 6mm.

In this fifth aspect, the laser system can have one or more of the features of the laser system as defined herein according to the second aspect of the invention.

In this aspect, the tip member can have one or more of the features of the tip member as defined herein according to the third aspect of the invention.

According to a sixth aspect, the present invention is a tip member for a laser emitting device, the tip member having an optical pathway having a first end, a second end, and extending through at least a portion of the tip member; wherein the device has at least one component having at least one aperture placed in the optical pathway, wherein any portion of a laser beam striking the component around said at least one aperture does not continue to travel through the optical pathway and any portion passing through said at least one aperture is free to continue at least past said component and further through the pathway.

According to a seventh aspect, the present invention is a tip member for a laser emitting device, the tip member having a body having a first end, a second end, and an optical pathway for a laser beam extending through at least a portion of the tip member; wherein the second end of the body comprises a face that is contactable with the skin of a patient; and further wherein a ring is removably mountable to the face and transferable to the skin when the face is applied thereto.

The tip members of these aspects can have one or more features of the other tip members defined herein.

Brief Description of the Drawings

By way of example only, a preferred embodiment of the invention is now described with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of one embodiment of a tip member according to the present invention for a laser emitting device;

Fig. 2 is a perspective view of the tip member of Fig. 1 with the cap member removed;

Fig. 3 is an end view of the tip member of Fig. 1 ;

Fig. 4 is a cross-sectional view of the tip member of Fig. 1 ;

Fig. 5 is an exploded perspective view of the tip member of Fig. 1;

Fig. 6 is a cut-away perspective view of an end portion of a laser emitting device of a laser system according to one embodiment of the present invention;

Fig. 7 is a cut-away perspective view of the end portion of Fig. 6 depicting a tip member in a first position relative thereto;

Fig. 8 is a cut-away perspective view of the end portion of Fig. 6 depicting a tip member in a second position relative thereto;

Fig. 9 is a schematic view of another embodiment of a laser system according to the present invention; and

Fig. 10 is a graph depicting the drop off in laser beam energy.

Preferred Mode of Carrying out the Invention

One embodiment of a tip member for a laser emitting device is depicted generally as 10 in the drawings. The laser emitting device 50 is part of a laser system

70 that emits a laser beam at an appropriate wavelength and energy so as to perforate, ablate, or otherwise alter skin with the purpose typically being administration of anaesthetics or other pharmaceuticals or the sampling of fluids, such as blood.

The depicted tip member 10 is constructed to be detachably mountable to a laser emitting device as is described in more detail below. The tip member has a main body

11 having a first end 12 and a second end 13. An optical pathway 14 for a laser beam emitted by the laser emitting device, when the tip member 10 is mounted to the device, extends through the main body 11.

The main body 11 has a first portion 15 that is engageable with the laser emitting device and a second portion 16. In the depicted embodiment, the first and second portions 15,16 of the main body 11 are integrally formed in comprising the tip member 10 together with a substantially triangular panel 40 that facilitates handling of the tip member 10 during use.

The optical pathway 14 of the tip member 10 is constructed so as to reduce the diameter of a laser beam passing therethrough that has a diameter greater than a predetermined diameter. This has the advantage of allowing use of laser beam having a lower peak energy, whilst having the same or similar average energy, as a beam of higher peak energy thereby reducing the likelihood of unwanted damage to the skin of the patient through use of the device.

In the depicted embodiment, a component 20 is provided that is comprised of a tube 17, an outer member 21 and a window 27 (see Fig. 4 where the se features are depicted assembled together and Fig. 5 where these features are depicted in exploded view). The tube has a first end 18, a second end 19, and has a constant inner diameter of circular cross-section along its length. The first end 18 of the tube 17 defines a first aperture for reducing or aperturing the diameter of the laser beam directed through the optical pathway 14. The tube 17 is positioned such that any portion of a laser beam striking the tube outside the bore thereof, if the diameter of the laser beam is greater than the diameter of the inner surface of the tube, does not continue to travel through the optical pathway 14. Any portion passing through the bore of the tube 17 is free to continue at least to the exit or second end 19 of the tube 17.

The energy fluence of a typical laser beam is not constant across its diameter but instead reduces near the edge of the laser beam. An example of the drop off in energy fluence adjacent the edges of the beam diameter is depicted in Fig. 10. In the depicted embodiment, the diameter of the bore of the tube 17 is set such that the portion of the laser beam passing through the tube has a relatively constant energy fluence or density across at least a portion of its diameter, and more preferably at least a majority of its diameter.

In the embodiment, the diameter of the bore of the tube is 6mm. While not restricted to this embodiment, the diameter of the laser beam when it enters the tube can be, for example, 8mm or greater.

While the depicted tube has a cylindrical inner surface, tubes having inner surfaces of different cross-sectional shapes to circles can be envisaged including ovals, squares, triangles and other multi-sided shapes.

The tube 17 comprises an inner member of the component 20 which also has an outer member 21. The component 20 is slidably housable within the second portion 16 of the main body 11. As depicted in Fig. 5, the inner member or rube 17 has an outer flange 17a that is frictionally engageable within the outer member 21.

The outer member 21 also has a first end 22 and a second end 23 with the second end 23 defining a face 24 surrounding an aperture 25 therein. A tubular member 26 extends back from around this aperture 25 for a distance towards the first end 22 of the outer member 21. In the depicted embodiment, the inner diameter of this tubular member 26 is slightly smaller than the diameter of the inner surface of the tube 17 comprising the inner member. A such, the end of the tubular member 26 distal the face 24 acts, in the depicted embodiment, as a second aperture for the laser beam passing through the optical pathway 14, again assuming the incident laser beam has had a diameter greater than the inner diameter of the tubular member 26. It will be appreciated where the laser beam had a diameter less than that of the first end 18 of the tube 17, the aperture provided by the distal end of the tubular member will comprise the first aperture for the incident laser beam provided by the tip member 10.

A window 27 is held between the end of the tubular member 26 and the second end 19 of the tube 17. In this embodiment, the window 27 is held in place by the relatively close fit that exists between the tube 17 and the outer member 21. The window 27 is transparent to at least light transmitted at some or all optical wavelengths and is constructed of a suitable polymeric material.

The face 24 at the second end 23 of the outer member 21 can, in use, be contactable with the skin of a patient. In the depicted embodiment, this face 24 supports a site identifier, in the form of an adhesively mounted ring 28 (see Fig. 1). The ring 28, in the depicted embodiment, is formed of a cloth surgical tape material. Following contact between the skin and the face 24, the ring 28 is transferable to the skin of the patient. The outer surface of the ring 28 is provided with an adhesive layer that facilitates adhesion of the ring 28 to the skin of the patient on contact therewith. The respective adhesive layers can have a different degree of adhesion to thereby ensure transfer of the ring 28 off the face 24 and onto the skin on contact with the skin. It is to be appreciated that the ring 28 could be provided on the tip member 10 irrespective of whether the tip member is adapted to reduce or aperture the diameter of the laser beam entering the tip member.

The depicted ring 28 is annular and has a slit 29 formed therein. A ring having more than one slit can be envisaged. An inner end of the slit 29 has a tapering portion or notch 31. A notch could instead or in addition be provided on the outer end of the slit. Assuming the laser beam is applied to the skin of the patient, the annular ring 28 left on the skin easily identifies the location of the skin that has received the laser beam. The notched slit 29 allows the ring to be relatively readily removed from the skin around an IV line and the like, if and when desired.

The second portion 16 of the tip member 10 comprises the wall of a chamber 32 having a cylindrical inner surface 33 (see Figs. 4 and 5) and a dimension that allows the component 20 to be slidably supported therein back to an abutment surface 30. The depicted second portion 16 also has an outer cylindrical surface 34 that receives a cap member 35 that is removably mountable over the second portion 16. The depicted cap member 35 is transparent and serves to protect the face 24 of the component 20 from inadvertent contact prior to use.

The component 20 is movable between a first position, as depicted in Fig. 4, and at least one second position, as depicted in Fig. 1, whilst still mounted to the tip member 10. The component 20 is adapted to be in the first position prior to the mounting of the tip member 10 to the laser emitting device and move to the second position during the mounting of the tip member 10 to the laser emitting device 50.

Once in the second position, the component 20 can be held by a retaining mechanism that prevents or substantially prevents further movement of the component 20. In the depicted embodiment, the retaining mechanism comprises a rim 36 on the outer surface of the outer member 21 that is engageable with a number of nodules 37 disposed on the inner surface of the chamber 32 of the tip member 10.

To mount the first portion 15 of the tip member 10 to the post or spigot 55 of the laser emitting device (see Figs. 6-8), the first portion is relatively slid over the spigot 55 and starts to relatively push back the wall 56 biased by spring 57. Once the tip member has been sufficiently inserted such that the outer end of the spigot 55 strikes the first end 18 of the tube 17, further relative movement of the tip member 10 onto the spigot 55 results in the entire component 20 moving relative to the main body 11 towards the second end 13 thereof. As such, the component 20 moves from the position depicted in Fig. 4 to the position depicted in Fig. 1 as the tip member 10 moves relative to the laser emitting device 50 from the position depicted in Fig. 7 to the position depicted in Fig.

The tip member 10 should preferably only be used once. Movement of the component 20 to the second position provides an indication to the user of the device that the tip member 10 has been used and should be replaced before next use.

One example of an end of a laser emitting device that can receive the tip member 10 is generally depicted as 50 in the drawings (see Figs. 6-8). The laser emitting device comprises a housing 51 for the componentry of the device. As depicted schematically in Fig. 9, the laser device 50 is part of a laser system 70. The system includes:

(i) a laser pump cavity 71 containing a laser rod 75, in the depicted embodiment Er: YAG;

(ii) a means for exciting the laser rod 75, i.e. a fiashlamp 76 supported within the laser pump cavity 71 ;

(iii) an optical resonator comprised of a high reflectance mirror 77 positioned posterior to the laser rod 75; and

(iv) an output coupling mirror 78 positioned anterior to the laser rod 75.

The system 70 can draw power from a mains source and/or one or more on¬ board rechargeable batteries 72. The power is used to charge up a bank of capacitors included in the high voltage pulse-forming network 73 of the system 70. A power interlock 74, such as a keyswitch, can be provided which will prevent accidental charging of the capacitors and thus accidental laser excitation.

The mounting of the tip member 10 controls energizing and firing of the laser emitting device. The laser emitting device 50 is provided with a number of switches that are activated on appropriate insertion of the tip member 10.

On initial insertion, the first portion 15 has a first tab 38 that engages a lever arm

52. The lever arm 52 extends back to a press button 53 which is biased by a spring 54.

On mounting, the first portion 15 is slid over the cylindrical post or spigot 55 and then starts to bear against the wall 56 which is biased outwardly by spring 57. A first movement of the wall 56 serves to close switch 58 (compare Figs. 6 and 7) that enables the laser system to energize. In this case, energizing is not automatic but is merely possible once switch 58 is closed. In other words, energizing only actually commences when the user depresses a button or pulls a trigger.

Further continued movement of the wall 56 leads to closing of switch 59 which enables the system to fire (see Fig. 8). Again, firing is not automatic but only occurs following depression of a trigger by the user. It is to be noted that it is a safety feature of the present invention to ensure that the unit will only fire if firstly switch 58 is closed, the device is energized, the switch 59 is closed, and then the trigger is depressed. In other words, a one-step mounting of the member 10 in which switches 58 and 59 are closed without allowing energizing to occur, will not allow the system to fire.

As depicted schematically in Fig. 9, the optical pathway of the laser system can further comprise at least one diverging lens 60, that is positioned within the housing 51, that causes the emitted laser beam to be expanding in diameter after passing through

the lens 60. The laser system having such a diverging lens can be used in conjunction with the tip member 10 or in conjunction with a different tip member. In another arrangement, it will be understood that the diverging lens could be mounted within the tip member 10.

Where used, the tip member 10 can be mountable to the laser system such that the diverging diameter of the laser beam entering the tip member is reduced or apertured to a maximum diameter of 6mm. As depicted in Fig. 10, the diverging lens can expand the diameter of the beam such that it is about 8mm when the beam enters the tube 17. As there is a significant drop off in the energy of the laser beam at the edges of the beam, this aperturing ensures that the energy of the beam delivered to the skin of the patient is substantially the same across a significant proportion of its diameter.

The laser element of the depicted system is an Er: YAG laser and is designed to emit a pulsed beam. The laser beam can have the following properties:

- a wavelength of 2.94 microns;

- an energy fluence of between 0.03 and 9.6J/cm ; and

- a pulse width of about 200 microseconds.

Other laser types having other properties are envisaged and encompassed within the present application.

The laser beam can create a site of alteration or ablation in the skin of the patient when the light beam is applied to the skin. The site of alteration or ablation can be circular or another shape, including slit-shaped. The site of alteration or ablation can have one or more therapeutic or other compounds subsequently applied thereto.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.