WO2004006793A1

WO2004006793A1 - An apparatus for tissue treatment

Info

Publication number: WO2004006793A1
Application number: PCT/DK2003/000492
Authority: WO
Inventors: Casper Dolleris
Original assignee: Asah Medico A/S
Priority date: 2002-07-11
Filing date: 2003-07-11
Publication date: 2004-01-22
Also published as: AU2003245861A1

Abstract

An apparatus for tissue treatment comprising means for varying the focused spot size of a treating light beam on a target area is provided. The apparatus comprises means for receiving a first light beam emitted from a first light source, at least two components, each providing a selected focused spot size on a target area, and a selector device being movable between at least two positions, each position corresponding to a component. When moving the selector device a selected component is positioned in a beam path of the first light beam, so that the selected component may emit a second light beam having the selected focussed spot size on the target area. The second light beam may be deflected or directed towards the target area by deflecting or directing means. Furthermore, a method for tissue treatment using the apparatus is provided.

Description

AN APPARATUS FOR TISSUE TREATMENT

TECHNICAL FIELD

The present invention relates to an apparatus for tissue treatment, the apparatus comprising means for varying the focused spot size of a treating light beam on a target area. Furthermore, the present invention relates to a method for tissue treatment using the apparatus.

BACKGROUND OF THE INVENTION

It is known to use an apparatus, e.g. in combination with a scanning device, for tissue treatment, such as described in US 6,190,376, US 6,074,382, and in US 6,383,177 hereby incorporated by reference. However, in the known apparatuses, the components constituting the apparatus, such as optical components, are 'fixed', i.e. they are impossible or at least very difficult to exchange with other components. Therefore, the known handpieces are designed for specific purposes or specific kinds of treatment, and/or to be used in combination with specific light sources. Thus, they are relatively inflexible and not easily adapted to other purposes or light sources than the ones they were originally designed to. Likewise, the spot size of an output light beam deflected towards a target area have a predetermined spot size on the target area, when the target area is in the focus point of the output light beam.

Some prior apparatuses have been modified so as to include a zoom arrangement. The zoom arrangement may be adapted either to change the distance between an output of the apparatus and the target area or to change the spot size at the target area by moving a lens back and forth.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an apparatus comprising a selector device being adapted to change a focused spot size of a light beam on a target area.

It is a further object of the present invention to provide for an electrically controlled change of the focused spot size.

It is a still further object of the present invention to provide an apparatus that is adapted to change the spot size using a stable mechanical system operating with low noise. According to a first aspect of the invention, the above-mentioned and other objects are fulfilled by an apparatus for tissue treatment comprising:

means for receiving a first iight beam emitted from a first light source, - at least two components, each providing a selected focused spot size on a target area, a selector device being movable between at least two positions, each position corresponding to a component, means for moving the selector device between said at least two positions, thereby positioning a selected component in a beam path of the first light beam, the selected component being adapted to emit a second light beam having the selected focused spot size on the target area in response to the first light beam being incident on the component, means for deflecting or directing the second light beam towards the target area, so that the second light beam has the selected focused spot size on the target area.

According to a second aspect of the invention a method of tissue treatment comprising adjusting a focused spot size of a second light beam on a target area is provided, the method comprising

- emitting a first light beam from a first light source, selecting a first focused spot size, moving a selector device between at least two positions, each position corresponding to a component, adjusting the focused spot size by positioning a correspondingly selected component in a beam path of the first light beam, the selected component being adapted to emit a second light beam in response to the first light beam being incident on the selected component, deflecting or emitting the second light beam towards the target area having the selected first focused spot size on the target area, so that the selected component is being adapted to provide the selected first focused spot size of the second light beam on the target area.

The focused spot size of the second light beam on the target area is, thus, adjusted by changing a component, such as a lens, being adapted to emit a second light beam in response to the first light beam being incident on the component. So when a first focused spot size is selected, a corresponding component providing the first focused spot size of the second light beam on the target area is selected. The first light source may comprise a coherent light source, such as a laser device, such as a C0₂ laser, a YAG laser, such as an Erbium YAG laser a Holmium YAG lasers, a Nd YAG laser, etc., a semiconductor laser, such as a laser diode, a pulsed laser, a gas laser, a solid state laser, a Hg laser, an excimer laser, an Optical Parametric Oscillator (OPO) laser, a metal vapour laser, etc. Alternatively, the first light source may be a non-coherent light source, such as a lamp, a light bulb, a flash lamp, etc.

It is preferred to adapt the components to the specific wavelength of the light source used, so that the at least two components of the selector device as well as other components, such as the deflecting means, of the handpiece are adapted to the specific wavelength of the light source. The light source may emit waves having a wavelength in the infrared part of the electromagnetic spectrum, such as in a wavelength range from 0,75 μm to 100 μm, such as in a near infrared part of the spectrum, such as from 0,75 μm to 1,5 μm, such as in a middle infrared part of the spectrum, such as from 1,5 μm to 30 μm, such as in a far infrared part of the spectrum, such as from 30 μm to 100 μm, in the visible part of the electromagnetic spectrum, such as in a wavelength range from 0,390 μm to 0,770 μm, and in the ultraviolet part of the electromagnetic spectrum, such as from 10 nm to 390nm, such as in the near ultraviolet part of the spectrum, such as from 300 nm to 390 nm, such as in the far ultraviolet part of the spectrum, such as from 200 nm - 300, such as in the extreme ultraviolet part of the spectrum such as from 10 nm to 200 nm.

Presently, lasers are a preferred light source and the light beam emitted from the laser is preferably coupled into an optical fiber delivering the light beam to the handpiece.

Present C0₂ lasers emit light at a wavelength of 10600 nm. The C0₂ laser is particularly well suited as a light source in an apparatus for ablating dermal cells as water has a high energy absorbance at 10600 nm and the C0₂ laser is capable of reliably delivering the required laser power.

Erbium YAG lasers emit light at a wavelength of 2930 nm. Water absorbs less energy at this wavelength that at 10600 nm. Therefore, the Erbium YAG laser may be preferred for ablating thinner layers of dermal cells than may be ablated with a C0₂ laser. Tissue having been treated with light emitted from an Erbium YAG laser may heal faster than tissue having been treated with C0₂ laser light as a thinner layer of dermal cells is influenced by Erbium YAG laser light. An Erbium YAG laser may also be preferred when photocoagulation of blood vessels is to be avoided.

A CO laser emits light in the 4500 nm to 5500 nm wavelength range. Water absorption at these wavelengths is somewhat less than water absorption at 10600 nm. A CO laser light source is presently preferred for dental treatment, e.g. for removal of carries, as dentine is not influenced by illumination of light from a CO laser.

A Nd Yag laser emits light at a wavelength of 1060 nm and is well suited for hair epilation by selective photo thermolysis, since light at this wavelength causes local heating of the hair bulb due to absorption of the light in the oxyhemoglobin contained in the capillaries.

A Nd YAG laser with a frequency doubled output beam in the 520-680 nm wavelength range is presently preferred as a light source for treatment of hypervasculation. Light in this wavelength range causes photocoagulation of blood without affecting surrounding tissue provided that an appropriate intensity of the light beam is directed towards the micro vessels for an appropriate period of time. Coagulation stops blood flow in the treated vessels whereby discoloration of the skin also stops.

A solid state diode laser emitting a wavelength of 810 nm is presently preferred for hair epilation by selective photothermolysis as this wavelength is absorbed by the melanin contained in the hair shaft. The hair bulb is thus damaged due to heat transportation through the hair shaft.

Typically, a power density greater than about 50 W/mm², such as a power density in the range from about 50 W/mm² to about 180 W/mm², is adequate for vaporizing cells with a minimum of damage to the surrounding tissue.

Generally, the power density is adapted to the wavelength and the tissue to be treated.

The deflecting means may comprise any optical component or components suitable for deflecting light emitted from the first light source, such as mirrors, prisms, diffractive optical elements, such as holograms, grids, gratings, etc.

In a preferred embodiment, at least the deflecting means and the selector device of the apparatus is positioned in a handpiece, which is a single unit for conveniently holding in one hand by an operator of the handpiece.

The deflecting means are preferably movably mounted for displacement of the deflecting means as a function of time, so that the light beam emitted from the apparatus, i.e. the second light beam, may traverse a target area along a desired curve while the apparatus is kept in a fixed position. Preferably, the deflecting means are rotatably mounted, and the actual deflection of the iight beam is determined by the current angular position of the deflecting means. Deflecting moving means, such as actuators, such as piezo electric crystals, may be utilised to control positions of the deflecting means, the displacement of which is controlled by applying a specific electric voltage to electrodes of the deflecting moving means. The deflecting moving means may comprise electromotors generating linear or rotational displacements, galvanometers, magnetically activated or controlled actuators, pneumatic actuators, hydraulic actuators, etc.

The positions of the deflecting means may be controlled by deflecting control means adapted to control the deflecting moving means so that the deflecting means deflect the light beam in such a way that it traverses a target area along a desired curve or in a predetermined pattern, (see for example US 6,190,376).

When the handpiece is kept in a fixed position in relation to a target area, and is emitting a second or third light beam towards the target area, changing of the position of the deflecting means causes the second or third light beam to traverse or scan the target area along a curve. An area may be traversed or scanned by the second or third light beam, e.g. by letting the second or third light beam traverse or scan a meander like curve substantially covering the area or, by traversing or scanning the area line by line. In the present context, the type, number and shape of curves traversed by the second or third light beam in order to traverse a specific area are denoted the traversing pattern or the scan pattern. The area that is scanned or traversed by the second or third light beam is denoted the scan area, the treatment area or the traversed area.

A light source for providing a visible aiming light beam may be provided, either in the handpiece or in combination with the first light source and be provided to the handpiece via a fiber. The aiming light beam may be adapted to be traversed around at least a part of the circumference of the target area thereby indicating the size, shape and position of the target area to be traversed with the second light beam. When a polygonal shape of the target area has been selected, the visible light beam may, e.g. between traversing by the second light beam, be traversed along one edge of the polygon. The aiming light beam is of particular interest when the second light beam is invisible. The aiming light beam may then assist the operator by indicating areas towards which the invisible light beam is directed during traversing. A second light source may provide the aiming beam.

The means for receiving the first light beam emitted from the first light source, may be provided with an inlet end for connection of the receiving means to the light source, for example via an optical fiber, and the receiving means may further be provided with an outlet end for emitting the first light beam into the apparatus or into the handpiece. The selector device may comprise an at least substantially circular disc or plate, in which case the means for moving the selector device comprises means for rotating the disc about an axis of symmetry of the disc. In this embodiment, the at least two components may be arranged annularly along the edge of the disc, and a specific component may be selected when a portion of the disc comprising that component is rotated into the path of the first light beam. Thus, the disc is preferably positioned with at least part of the edge region in the beam path, such that when the disc is rotated the components are consecutively positioned in the beam path. The rotation may be stopped when a desired component is positioned in the beam path, the component thereby being selected.

Alternatively, the selector device may comprise an elongated plate, in which case the means for moving the selector device comprises means for moving the plate at least substantially linearly along a longitudinal axis of the elongated plate. In this embodiment the at least two components may be arranged along a longitudinal axis of the plate, and a specific component may be selected when a portion of the elongated plate comprising that component is moved linearly into the path of the first light beam. This is similar to the embodiment described above, except that in this case the components are arranged in a row and the plate is moved at least substantially linearly, e.g. sideways or in an up/down direction. The plate is preferably positioned in the beam path in such a way that when it is moved substantially linearly along the longitudinal axis of the plate, the components are consecutively positioned in the beam path. As described above, a component may be selected by stopping the movement when that component is positioned in the beam path of the first light beam.

It is envisaged that the selector device may have any form suitable to be positioned in the apparatus or in the handpiece so that the at least two components in turn may be positioned in the beam path of the first light beam. The selector device itself may for example be provided with impressions, indentations, etc. to allow for positioning of the at least two components, so as to for example ease mounting of components having different size and shape, etc.

The selector device may have a size, which is capable of supporting the desired components, and at the same time have a size so that it may be positioned within the apparatus or the handpiece. For a selector device to positioned in a handpiece and comprising a circular disc, the diameter of the disc may be 25-50 mm, such as 30-40 mm, such as preferably 36-40 mm. For a selector device to be positioned in a handpiece and comprising an elongated plate, the plate may be 25-60 mm long. The handpiece may be provided with 'bumps' of finger-holds on the outside to make room for the selector device in the inside of the handpiece. The selector device may be mounted in the apparatus or the handpiece so that an exchange or an replacement of the selector device may be performed by e.g. an operator of the apparatus or, alternatively, by a technician performing maintenance of such apparatuses. Hereby, the components may be exchanged by other components, either in case of a broken component or if another treatment make use of other components. A number of premounted selector devices may, thus, be provided with the apparatus or handpiece. A corresponding software package may accompany the selector device or, alternatively, be pre-installed in the handpiece, such as in an electronic memory, such as an EEPROM, of the handpiece.

The means for moving is, preferably, electrically controlled so that a user selection of a desired component causes a signal to be sent to the moving means whereby the moving means are controlled to move the selector device so that the desired component is positioned in the beam path of the first light beam. Alternatively, the means for moving the selector device may be mechanical means, so that the selector device may be moved e.g. by rolling a knob, turning a wheel, for example by turning a projecting part of the selector device, etc.

It is an advantage, that the means for moving may be controlled electrically so that the selector device may be changed by a command from the first light source, or may be controlled according to a pre-programmed software.

Furthermore, the change of components may be performed quietly, which has a significant impact on the comfort experienced by a user or operator of the handpiece as well as a patient being treated. The moving means may, furthermore, be adapted to position the components very fast, accurate and with a high repeatability. The components may, for example, be positioned with a repeatability better than 500 μm, such as better than 100 μm, such as better than 50 μm. It is an advantage of the accurate positioning of the components that the optical losses due to misalignment of the components are minimized. The positioning time for the components may be in the range of 10-500 ms, such as 10- 200 ms, such as 50-200 ms, such as 100-200 ms, preferably such as 150 ms, e.g. for half a turn of a circular disc in the selector device. The positioning time or the positioning speed may be software controlled so that the overall impact on the handpiece may be varied, that is the noise, the power consumption, the mechanical wear, the mechanical shake, etc. By controlling the positioning time, the mentioned parameters may, thus, be tailored according to the actual application. By, for example, lowering the speed or the positioning time in non-critical applications, an even quieter movement may be achieved. The selector device and the means for moving may, preferably, be manufactured so that the mechanical function is very stable whereby minimizing the mechanical shake. The selector device is preferably inserted in the beam path between the receiving means for receiving the first light beam and the deflecting means.

The at least two components, each providing a selected focused spot size on a target area, may be lenses so that the spot size at the target area may be varied by selecting optical lenses having varied optical parameters. The optical parameters may comprise the aperture, the focal length, etc. of the lens and the optical parameters may further comprise the distance from an out-let end of the means for receiving the first light beam and the lens. By varying these optical parameters, simple raytracing will show that the spot size at the target area may be changed. By changing the distance between the out-let end of the receiving means and the lens according to the selected spot size, the distance from an output of the apparatus to the focus plane, i.e. the target area, may be held substantially invariant. Of course, also other optical parameters of the lenses may be varied concurrently with the variation of the length between the out-let end and the lenses.

Alternatively, the distance between the out-let end of the receiving means and the lens may be kept substantially constant while varying other optical parameters of the lens for varying the spot size at the target area. Hereby, the distance to the focused spot size at the target area will vary accordingly.

To ensure that the second light beam is focused on the target area, a distance piece may be provided, and the distance between an output of the apparatus and the target area may be adjusted according to the selected spot size. The distance piece may either be a telescopic distance piece, preferably provided with marks or fasteners at a number of distances corresponding to the distance from the output of the apparatus to the target area where the second light beam is focused. Alternatively, a number of distance pieces may be provided, the distance pieces preferably being removable attached so as to facilitate easy exchange of the distance pieces, and, furthermore, for facilitating autoclaving of the distance pieces.

It is, however, preferred to change the distance between the out-let end of the receiving means and the lens according to the selected spot size, so that the distance from an output of the apparatus to the target area, may be held substantially invariant so that only a single distance piece is needed during treatment, even when the spot size is changed. It is preferred that also this distance piece is removably attached so as to facilitate autoclaving of the distance piece. This provides a very flexible apparatus wherein the spot size of the second light beam on the target area may easily be selected according to the specific purpose or patient.

Furthermore, the spot size may be changed during a treatment session, e.g. in order to provide a very homogeneous treatment and/or in order to avoid unnecessary overlap between treated areas and/or in order to avoid untreated areas.

It is an advantage that the spot size at the target area may be selected by simply changing the lens at the selector device without changing any other parts of the deflecting means and without changing any output lenses or the position of any of the output lenses, of the apparatus.

Any number of lenses may be positioned on the selector device, such as 2, 3, 4, preferably such as 5, even up to 10, or up to 15 lenses may be positioned on the selector device. When positioning the apparatus in a handpiece, the size of the handpiece may limit the number and the sizes of the lenses.

By changing the lenses, different spot sizes may be obtained on the target area, such as a spot size between 0.1 mm and 20 mm, such as a spot size between 0.1 mm and 10 mm, such as a spot size between 5 mm and 15 mm, such as a spot size between 1 mm and 10 mm.

It is an advantage that a large variation in spot sizes may be obtained by an apparatus according to the present invention. The large variation of the spot sizes provides a high degree of freedom in relation to the design of predetermined patterns, etc.

The selector device may comprise a third component so that the selector device comprises at least three components, at least one of the at least three components may be adapted to provide one or more specific functions, such as a specific functionality selected from a group consisting of sensing, emitting a third light beam, emitting no light beam and emitting a second light beam in response to the first light beam being incident on the selected component.

At least one of the at least three components may be another optical component, such as a reflective mirror, a prism, a diffractive optical element, such as a hologram, a grid, a grating, etc.

In case at least one of the components is a diffractive element, the element may be used, e.g. in combination with a second light source, so that a predetermined pattern, preferably the predetermined pattern in which to traverse the target area, or a circumference of the predetermined pattern, is shown on the target area. Furthermore, a diffractive optical element may be used as a beam transforming element, e.g. in combination with a lens, such as in combination with each of the at least two lenses, so as to provide for spots on the target area having any arbitrary shape, such as polygonal, such as rectangular, quadratic, triangular, etc, or circular, elliptic, etc. It is hereby possible to design e.g. a pattern having substantially no areas which are not treated.

Furthermore, at least one of the at least three components may be a sensor or a detector providing information about the target area. The information provided may for example comprise information about tissue parameters, such as colour, temperature, texture, elasticity, size, shape, reflectivity, and scattering properties, etc. Tissue may hereafter be classified into specific tissue conditions, such as tissue types, skin disorders, cutaneous damage, etc., according to predetermined values of the various tissue parameters or by values of mathematical functions of such parameters. Further, the functions may include averages, weighted averages, correlations, cross-correlations, etc, of mathematical functions.

Such tissue conditions may comprise any cutaneous damage, skin disorder or skin irregularity, such as wrinkles, small marks on the tissue, such as marks from chloasma, liver spots, red spots, tattoos, blood vessels, beauty spots, freckles, etc., as well as warts, wounds, moles, hair follicles, tumours, etc., as well as tissue types of the target area, such as very light skin, light skin, dark skin, darker skin, etc. The apparatus according to the invention may be used for removing skin disorders by ablation, removing vascular disorders by vessel coagulation, wrinkle removal by subcutaneous collagen denaturation, etc. Furthermore, the apparatus of the invention may be used for tissue stimulation, for therapeutic purposes, such as reduction of pain, such as reduction of inflammation, reduction of erythema, promotion of processes of photobiostimulation, etc. Hereafter, the terms tissue and resurfacing and treatment will include these marks and treatments thereof, and treatment will further include tissue stimulation and therapeutic use.

For example, various marks may be detected by their colour. Thus, the sensor may comprise light detectors for detection of intensity of light emitted from tissue at the target area, the target area being the area to be treated by the first light beam or being the area the apparatus is currently directed at.

Certain tissue conditions, such as small marks on the tissue such as marks from chloasma, liver spots, red spots, tattoos, blood vessels, beauty spots, freckles, etc, to be treated may be characterised by the shape or the size of the area covered by the tissue condition in question. For example, when treating different types of marks of substantially identical colours, it may be desirable to treat each type of mark differently and according to the respective size or shape of the type of marks in question.

Some marks on the tissue may be have a substantial circular circumference, so that specific marks may be treated by the apparatus and a spot size selected according to the circumference of the spot.

When removing hairs, it is important to identify the type of tissue on which the hairs are to be removed in order to specifically customise the hair removal towards the tissue type in question and the corresponding colour of the hairs to be removed.

The sensor may be a camera, such as a video camera, such as a charged-coupled device (CCD) camera, or a complementary metal-oxide semiconductor (CMOS) camera. The sensor may, furthermore, be a detector, such as a wavelength sensitive detector, an intensity sensitive detector, etc. The sensor may be one or more array(s) of sensors or it may be a single sensor or detector, sensing information from one position or one pixel at a time, thus collecting information of at least part(s) of the target area during scanning of the target area so that reflected light from at least a part of the target area reaches the sensor during scanning of the target area.

Still further, another of the at least three components may comprise another sensor providing further information about the target area and the tissue at the target area. Different sensors may for example be sensitive to reflected light in different wavelength ranges, or a number of sensors may be applied so that the combined field of view for the number of sensors encompass the target area. Especially when using sensors having a high resolution, the field of view of a single sensor may not be able to encompass the entire target area. A number of different sensors may e.g. be combined at a single component or a single component position on the selector device.

The camera may be connected to a display or a monitor and thus be used as a microscope for enlarging at least part(s) of the target area. Furthermore, the display may show illumination by non-visible light sources, such as an image of ultra-violet illumination, such as an image of infra-red illumination, etc. Still further, the display may trace the second light beam and, thus, display the second light beam, or another light beam, during traversing of the target area.

The sensor may be adapted to provide an image of the target area before, during and/or after treatment, thus for example facilitating comparison of the target area before and after treatment, either visually or by image processing. The image of the target area may be an image of any of the tissue parameters mentioned above, such as colour, temperature, etc, or it may be an image of a mathematical function of any of such parameters.

Further, light sources emitting light of different predetermined wavelengths may be directed towards the target area. For example, the light sources may comprise two light emitting diodes, one for emission of light in the wavelength range where the light is considered red and the other for emission of light in the wavelength range where the light is considered green. Also, the light sources may comprise three, four or even more light emitting diodes for emission of light of different wavelength ranges. The light sources may alternatively emit light in the ultra violet or infrared wavelength range. Light from the light sources is transmitted towards the target area and is reflected by tissue at the target area. The reflected light is detected by the detector means and the intensity of reflected light in the two or more wavelength ranges in question characterises one or more parameters of tissue that is illuminated. According to the wavelength selected, different parts of the tissue may reflect the light. Illumination of a tissue target area with a light source emitting light in the wavelength range considered orange may for example improve visualization of blood vessels and vascular disorders, while illumination with bluish light will conceal the same structures and improve visualization of less vasculated regions.

The image of the target area may be adapted to control the treatment just completed, or the images may be stored to provide documentation of the treatment, for example when doing clinical research. Furthermore, one or more images may be stored for documentation of tissue conditions of the target area.

Alternatively to positioning the sensor on the selector device, the sensor may be positioned behind the deflecting means. Hereby, the sensor may be used during treatment, i.e. while treatment is in progress, so that a feedback during treatment is facilitated. The deflecting means behind which the sensor is positioned may then be provided with special coatings so as to allow for at least partial transmission of light reflected from the target area to the sensor.

For example, when two light sources are utilised for detection of tissue parameters, predetermined reflected light intensity value ranges for the two wavelength ranges may be stored in a memory of the handpiece. During treatment, measured values of reflected light intensity are compared with the stored predetermined ranges and when measured values are within the stored ranges, treatment is enabled and otherwise it is disabled. The information from the sensor may be displayed on a monitor or a display, such as a CRT, a VFD, an OLED, an LCD, a TFT display, etc. The display may be positioned on the handpiece or it may be an external display coupled to the handpiece. The external display may be connected to the handpiece via a wireless connection, such as a blue tooth connection.

The displayed information may comprise a map of tissue parameters. Furthermore, the handpiece may comprise image-processing means for processing the map for enhancement of selected tissue conditions.

Tissue conditions may be displayed as graphical three-dimensional plots showing surface profiles of selected mathematical functions of tissue parameters of the mapped area.

Alternatively, tissue features or tissue conditions may be displayed as a colour map, i.e. predetermined ranges of values of a selected mathematical function of tissue parameters are allocated selected colours to be displayed in areas of the map mapping tissue areas with the respective function values.

The specific tissue conditions or tissue types may hereafter be treated differently for example by controlling parameters of the first light beam in response to the detected tissue parameters and/or tissue conditions.

Furthermore, user interface means for user selection of specific mapped tissue areas for treatment may be provided. Hereby, only specific areas containing e.g. warts or moles may be treated without treating areas containing no marks or areas containing e.g. freckles. The specific mapped tissue areas may be of different sizes and shapes, i.e. a specific mapped tissue area may have a shape, which substantially corresponds to the circumference of a corresponding wart or mole on the tissue.

The display may comprise a touch screen for displaying the tissue map and an operator of the handpiece may select a tissue area for treatment by touching the corresponding area on the touch screen.

Alternatively, the user interface means may conventionally comprise a mouse or a track ball for moving a pointer on the display unit for pinpointing tissue areas to be treated.

The user interface means may further provide for selection from a number of predetermined patterns, setting of parameters, etc. The selection and setting of patterns and parameters may be performed by buttons, jog dials, etc. Furthermore, the buttons may be configurable soft-buttons allowing for future software upgrades so that for example implementation of new applications may be performed without any hardware changes.

At least one of the at least three components may be a sensor for measuring the power of the first light beam. Hereby, the measured power and/or fiuence may be displayed on the display.

The sensor for measuring the power of the first light beam may be any power sensor, such as a silicon power sensor, a thermopile, a thermal volumetric power sensor, etc.

In some applications, it is of importance that the real value of the output power is known in order to obtain a consistent and uniform treatment, e.g. throughout the day or throughout the month, independently of the age and condition of the apparatuses and light sources used. By measuring the actual power of the first light beam in close proximity of the target area, i.e. after being emitted from the optical fiber, a control signal indicating the measured power may be provided to the light source so that parameters of the first light source may be adjusted according to the measured power of the first light source.

Alternatively, manual tuning of parameters of the first light source may be performed by the operator according to the measured power of the first light beam.

At least one of the at least three components may provide a shutter function, so that the first light beam may be turned on and off at the handpiece, without turning on and off the first light source. When, for example, the first light source has slow turn on and turn off times, the shutter may be used to optically and/or mechanically turn the light source on and off. The on/off time for the shutter may be less than 150 ms, such as less than 100 ms, preferably less than 50 ms, such as less than 25 ms. The shutter turn on/off time will, naturally, be dependent on the mechanics of the selector device.

The shutter may be operated on the basis of an output produced by a sensor measuring characteristics of the first light beam. The sensor may for example be a power meter sensor and the shutter may be opened, if the power of the first light beam increases above or decreases below certain predetermined power levels. The measured power of the first light beam may, thus, be compared to a predetermined threshold value, and the shutter may be opened when the power of the first light beam exceeds the predetermined threshold value. The target area may then be treated according to predetermined settings and by means of the second light beam. The shutter is then closed when the target area has been treated according to the predetermined settings. Furthermore, the shutter may be operated on the basis of an output produced by processing means analysing measured beam parameters, such as wavelength, intensity, dwell time, pulse duration, duty cycle, etc., of the first light beam. The measured beam parameters may be provided by the sensor connected to the processing means. The sensor may for example be a sensor for measuring the power of the first light beam, and the processing means may analyse the measured power, the spot size irradiated by the treating light beam (which spot size may be predetermined), etc., and further operate the shutter according to a corresponding output, the output, in this specific example, controls the shutter so that the time of irradiation of the spot size is controlled to provide a specific fiuence on the target area.

The predetermined settings may comprise settings regarding the total duration of the treatment, number of light pulses, accumulated light pulses, and/or settings regarding the traversing pattern of the second light beam on the target area, so that the shutter is closed when the second light beam has performed the traversing pattern. Furthermore, the settings may comprise settings regarding the treatment time at each position being treated.

For safety reasons a continuous comparison of the power of the light source and another predetermined threshold may be performed, so that the shutter may be closed if the power of the light source exceeds the other predetermined threshold.

The user may be alerted when the shutter has been closed. The user may furthermore be alerted if the temperature of the shutter exceeds a predetermined threshold temperature.

The apparatus may further comprise shutter cooling means, such as cooling fins, for cooling the shutter and/or the power sensor. The shutter and/or the sensor for measuring the power of the first light beam may both be exposed to heat corresponding to the power level of the first light source. For medium and high power light sources, some kind of cooling may be needed to cool the sensor and/or the shutter. Cooling fins may, for example, be provided and mounted at the shutter and/or the sensor.

Alternatively, at least one of the at least three components may be a reflecting mirror being adapted to reflect at least a portion of the first light beam. The handpiece may then comprise absorbing means being adapted to absorb at least a substantial part of the light beam being reflected by the at least one reflecting mirror(s). The absorbing means may for example be positioned on an inner surface of the handpiece. The absorbing means may comprise a heat sink or, alternatively, a stationary heat sink may be mounted on an inner surface of the apparatus or a heat sink may be mounted on the outside of the apparatus being in thermal contact with the absorbing means.

The apparatus may furthermore comprise a detector device for receiving at least a portion of the light beam being reflected by the at least one reflecting mirror(s), thereby gaining information relating to said light beam, and producing a corresponding output.

The detector device may be positioned on an inner surface of the apparatus. The detector device may, for example, be a power meter for measuring the power of the first light beam. Furthermore, other parameters and/or properties of the first tight beam may be measured, such as wavelength, intensity, dwell time, pulse length, etc. The apparatus may be operated on the basis of the produced output.

Especially when using high power light beams, it is an advantage to have a reflecting component positioned in the beam path of the first light beam when measuring or shutting off the first light beam, so that the components at the selector device are not excessively heated. Furthermore, when a high power light beam is directed or deflected into detectors, cameras, etc., large demands are made on the detectors in respect of quality, durability, etc. Furthermore, providing a high power light beam to a detector may imply that cooling of the detector may be necessary or desirable, whereby placement of the detector on the selector device may be inconvenient.

Another advantage of using a reflective component on the selector device for selecting one or more of the at least two components on the selector device, is the space requirements of the components which may be easier to comply with when the components are positioned away from the selector device, for example on an inner surface of the apparatus.

It is envisaged that more optical elements may be combined at the individual components of the selector device. For example, one component of the selector device may comprise a diaphragm and a collimator apart from one of the at least two lenses. Hereby, a more well defined light beam may be directed towards the deflecting means enhancing the optical properties of the second light beam. Another example may be the combination of a shutter and a sensor, so that one component of the selector device comprises a sensor providing information about the target area, such as properties or parameters of the target area and the tissue at the target area, and a shutter for shutting off the first light beam. The first light source is, thus, not turned off at the light source during sensing but is merely shut off by the shutter. The shutter may, furthermore, be a combination of a reflective mirror mounted at the component along with the sensor, and absorbing means adapted to absorb the reflected beam. In this example, the shutter or the reflective mirror may be provided on the reverse side of the sensor.

Still further, different filters may be inserted in front of one or more of the component(s) such as in front of a camera or a sensor so as to alter the relative intensity of the different wavelength components of the light beam incident on the camera or sensor. The filters may for example be positioned on another selector device, the other selector device being adapted to move independently of the selector device comprising the camera or sensor.

The deflecting moving means may be adapted to cause the second or third light beam, if present, to traverse the target area in a predetermined pattern. The predetermined pattern may for example be one or more straight lines, so that the second light beam traverses the target area line by line. Hereby, target areas of any arbitrary shape, such as polygonal, such as rectangular, quadratic, triangular, etc, or circular, elliptic, etc, may be traversed line by line by appropriately controlling the starting point and stopping point of light emission along each line traversed. The lines may be traversed sequentially i.e. neighbouring lines are traversed successively. The lines may be traversed in a meanderlike pattern or, preferably, the lines may be traversed starting from the same side and, still further, it is preferred to use the shutter to prevent emission of the second light beam towards the target area during repositioning of the deflecting means. Alternatively, an interlacing pattern may be used.

A scan pattern employing more than one spot size may be provided. The at least two lenses may thus be the lenses having various optical parameters resulting in various spot sizes on the target area, depending on the component selected. A spot size is, thus, selected by selecting a lens providing a spot of the corresponding spot size, and the target area is traversed in a predetermined pattern of spots having the selected spot size. Subsequently, a second spot size is selected by selecting a lens providing a spot of a corresponding second spot size, and the target area is traversed in a second predetermined pattern of spots having the second spot size.

The target area may, thus, be traversed two or more times. The target area may for example be traversed a first time by the second light beam having a first spot size on the target area, followed by a second traversing by the second light beam having a second spot size on the target area. The first spot size may be a relatively large spot size filling the target area with a limited number of treatment spots, whereafter the second traversing wherein the second light beam has a second, relatively small, spot size on the target area so as to fill in the space between the treatment spots of the first size. The speed of the scanning may thus be increased by the use of relatively large spot sizes while the uniformity of the scanning pattern is intact.

For example when removing hairs, the target area may be traversed a first time by the second light beam having a relatively large spot size and a fiuence selected to treat unwanted hair growth. The treatment of excessive hair growth may require a number of treatments, e.g. over months, before a visible result is obtained. A second scan having a power density being high enough to carbonize the hair shafts may, thus, ensure a visible result event after the first treatment. The higher power density may be obtained by keeping the laser power setting constant while selecting a smaller spot size.

Furthermore, a first scan may be performed for collection of information regarding the target area, such as information about tissue conditions, etc., followed by a second scan for treatment of the target area in response to the collected information. The target area may for example be illuminated by a second light source, such as a white light source, and the reflected light from the target area may be detected by the detector and analysed so as to characterise the tissue that is illuminated. The following treatment scan may then treat the entire target area or selected part(s) of the target area, and control parameters of the second or treating light beam according to the information collected. The second light source may be a light source illuminating substantially the entire target area or the second light source may illuminate one spot on the target area and be adapted to traverse the target area while information of the reflected light is provided to the detector. Having a second light source illuminating substantially the entire target area, collection of information may either be taken by a camera, such as a CCD camera, collecting information of substantially the entire target area at the same time, or the information may be collected from one spot at a time, deflecting reflected light from the target area onto the detector during scanning of the target area.

The handpiece may, still further, comprise tissue cooling means for cooling the tissue of the target area. Depending on the power dissipation in the tissue, the wavelength used, etc., the tissue will be heated during treatment. In order to minimise damage to the tissue not to be treated, a tissue cooling means may be provided to reduce the temperature of the tissue before, during and after treatment.

The handpiece may further comprise at least one second light source for providing illumination of the target area. By illuminating the target area, sensing of, e.g. tissue parameters, is more easily facilitated. Furthermore, it is an advantage to illuminate the target area so as to increase the visibility of the target area for the user. The at least one second light source(s) may be one of the at least three components. Hereby, different light sources may be used, for example, for illumination of the target area before and after treatment. The second light source may also be used during sensing while sensing with an optical detector when the optical detector is not positioned at the selector device. Alternatively, one of the at least one components at the selector device may comprise the second light source as well as an optical detector.

Furthermore, at least one of the at least one second light source(s) may be mounted on the distance piece defining the distance between the output of the handpiece and the target area. Hereby, larger second light sources may be used. Furthermore, higher power second light sources may be used if the airflow is sufficient and if adequate heatsinks are provided. However, the positioning of the light source may imply that the light is illuminating the target area under an angle, whereby shade effects may occur.

Still further, at least one of the at least one second light source(s) may be mounted at or near the output of the handpiece. The at least one second light source may, thus, be mounted at or near the deflecting means, such as at or near an output lens of the handpiece. For example, a row of light emitting diodes (LED's) or incandescent lamps may be provided around the output lens. Furthermore, different types of light sources may be provided at the same time thereby providing a choice of illumination wavelengths. By positioning the at least one second light source around the output lens of the handpiece an illumination of the target area having substantially no shade effects is obtained.

At least a substantial part of the light output of at least one of the at least one second light source(s) may have a wavelength in the infrared part of the electromagnetic spectrum, such as in a wavelength range from 0,75 μm to 100 μm, such as in a near infrared part of the spectrum, such as from 0,75 μm to 1,5 μm, such as in a middle infrared part of the spectrum, such as from 1,5 μm to 30 μm, such as in a far infrared part of the spectrum, such as from 30 μm to 100 μm. Alternatively or concurrently, at least a substantial part of the light output from at least one of the at least one second light source(s) may have a wavelength in the visible part of the electromagnetic spectrum, such as in a wavelength range from 0,390 μm to 0,770 μm, and alternatively or concurrently, at least a substantial part of the light output from at least one of the at least one second light source(s) may have a wavelength in the ultraviolet part of the electromagnetic spectrum, such as from 10 nm to 390nm, such as in the near ultraviolet part of the spectrum, such as from 300 nm to 390 nm, such as in the far ultraviolet part of the spectrum, such as from 200 nm to 300 nm, such as in the extreme ultraviolet part of the spectrum such as from 10 nm to 200 nm. There may, thus, be provided a plurality of second light sources each light source emitting, at least partly, light in the ultraviolet, visible, and/or infrared part of the electromagnetic spectrum. The light from the plurality of second light sources may then be combined to suit the desired application.

The second light source(s) may be any light sources capable of illuminating the target area, such as LED's, such as high brightness LED's, full colour LED's, infrared (IR) LED's, or ultraviolet (UV) LED's, such as laser diodes, krypton lamps, such as small lens-end krypton lamps, such as infrared (IR) lamps, incandescent lamps, such as small lens-end regular incandescent lamps, etc. For example, for illumination during sensing, high power low lifetime light sources, such as incandescent light sources, krypton light sources, such as halogen lamps and bulbs, etc., may be used by ensuring that the light sources are only turned on during sensing. Generally, LED's have longer lifetime (100000 hours) and higher efficiency while incandescent and krypton light sources have higher output and lifetime in the range of 1000-100000 hours.

The apparatus may still further comprise means for displaying an image on the target area. The image may be displayed by means of light, at least a substantial part of which has a wavelength in the visible part of the electromagnetic spectrum. The means for displaying an image on the target area may comprise a light source such as one or more light emitting diode(s) (LED's), and/or one or more laser diode(s). Furthermore, the image may be displayed by means of light having various wavelengths and/or by means of light having various intensities.

When the deflecting means is adapted to cause the treating light beam to traverse the target area in a predetermined pattern, the image displayed on the target area may for example outline the area(s) of the target area that will be treated if a corresponding pattern is selected.

The scan pattern within each area may further be displayed on the tissue, so that the predetermined patterns, including any fade-in and fade-out effects, are shown on the tissue. The image may be displayed using full colour LED's or laser diodes.

Information of the target area may be collected by a sensor and provided to image processing means, such as a processor, for generating an optimal pattern in which to treat the target area. An image of the generated pattern may be shown directly on the tissue. The user may accept the generated pattern and choose to treat the target area according to the generated pattern or the user may modify the generated pattern, so that for example, specific areas are not treated, etc. Furthermore, the user may be able to modify the chosen parameters of the first light source before treatment is initiated.

The handpiece may, furthermore, comprise a display, such as a graphical display, so that an image of the generated pattern may be shown on the display in addition to or alternatively to providing the image at the target area. The display may also show information regarding the optimal parameters of the first light beam. The user may then provide changes to the generated pattern as well as to the generated optimal parameters of the first light source, etc. before the treatment scan is initiated.

The display may, for example, be mounted on an upper surface of the handpiece. Hereby, the user may be able to see the display irrespective of which hand is used. The image may be adapted to be rotated digitally, so that a rotation of 180 degrees when the hand is changed ensures that the image and any text on the display will turn upside down. Furthermore, soft buttons may be digitally (re)configured to the hand used by the operator. Alternatively, the display may be able to display information in a user specified direction by mechanical means, so that the display may be hinged or rotatably mounted in any other way so that the user may decide the position of the display, e.g. according to which hand is used to hold the handpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a side view of a selector device, positioned in a beam path of a light beam,

Fig. 2 shows a top view of a circular selector device, comprising numerous components,

Fig. 3 shows a motor driven zoom lens system, wherein the zoom lens system is positioned in a beam path of the light beam before the light beam is deflected onto the target area,

Fig. 4 shows a motor driven zoom lens system, wherein the zoom lens system is positioned in a beam path of the light beam after the light beam is deflected by deflection means,

Fig. 5A and 5B show scan patterns employing multiple spot sizes. DETAILED DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a side view of a circular selector device 1 in an apparatus 9 having three lenses 2, 3, 4 arranged annularly along the circumference of the edge of the selector device 1. The selector device 1 may comprise more components than the three lenses 2, 3, and 4, see Fig. 2. The selector device 1 is rotably mounted on an axis of symmetry 5 of the selector device 1. A first light beam is emitted from a light source (not shown) through optical fiber 6, via receiving means 7 which has an out-let 8, through which the first light beam is emitted into the apparatus 9. In Fig. 1, it is seen that the lens 4 is positioned in the beam path of the first light beam. A second light beam is emitted from the lens 4 in response to the first light beam being incident on the lens 4. The lens 4 is a collimating lens so that the second light beam is a collimated light beam. The collimated second light beam is then deflected by deflecting means 10 towards a target area 11 via output lens 12. Output lens 12 focus the second light beam on the target area. The deflecting means may be replaced by directing means 10 for directing the second light beam towards the target area 11.

It is further seen that in Fig. 1, the lenses 2, 3, and 4 are mounted at distances d2, d3, and d4, respectively, from the selector device 1. The distances d2, d3, and d4 are chosen so that the deflected second light beam is focused on the target area, even without changing the output lens 12. When the lens 4 is chosen at the selector device and positioned in the beam path of the first light beam a spot size of 8 mm is obtained at the target area. When choosing lens 2 or lens 3, spot sizes of 2 mm and 4 mm, respectively, are obtained. It is an advantage that no other elements of the apparatus 9 has to be changed in order to achieve another spot size at the target area. It is, thus, not necessary to change, e.g., the output lens 12 nor the distance 13 between the output lens 12 and the target area 11.

It is also shown in Fig. 1 that the spot is not necessarily of a circular form. By inserting a diffractive element in the light path of the first light beam, e.g. in combination with a lens on the selector device, any shape of the spot may be obtained, such as any polygonal shape, such as rectangular, triangular, trapezoidal, etc. Thus, not even just different spot sizes but also differently shaped spots may be obtained on the target area to suit the specific application.

The selector device 3 is rotatably movable about the symmetry axis 5 and the means for moving 14 is a geared motor and an encoder adapted to provide a high degree of repeatability. This mechanical construction is simple and reliable. The motor is a 1516SR Faulhaber motor with a 22: 1 zero backlash spur gearing and a magnetic 512 position encoder, e.g. an IE2-512, so that there is no risk of optical disturbances by any of the light sources. This combination provides a fast positioning time in the range of 100-200 ms for half a turn and a positioning resolution of 0.0016 deg, which is 3.3 μm with a 12 mm circumference of the disc (corresponding to 22528 encoder pulses per round). The pre- tensioned zero backlash gearing allows for a low noise operation and an accurate steady state positioning without introducing the backlash of normal spur gears, usually 2-4 deg. The motor construction consumes no power in a fixed position and only little power while moving and are furthermore rated for 10000 hours of continuos operation. The electrical communication with the disc components may be a flexible PCB, such as a PFC. A plug (not shown) may be provided to facilitate exchange of selector devices.

In Fig. 2 a top view of the circular selector device 1 of Fig. 1 is shown. The selector device 1 comprises 7 component positions. It is seen that the three lenses 2, 3, and 4 are mounted on the selector device along with a sensor 16, a shutter 17, a guide beam light emitting diode 18, and a component 19 comprising a camera for obtaining an image of the target area and, on the reverse side facing the out-let of the fiber, a power meter for measuring the power of the first light source. The image may be shown on display 15 shown in Fig. 1.

It is envisaged that any elements and any combination of elements may be provided on the selector device. It may for example be an advantage to position a reflective mirror in the beam path of the first light beam instead of a traditional shutter. The reflective mirror reflects the first light beam towards an inner surface (not shown) of the apparatus 9, the inner surface preferably comprising absorbing means for absorbing the first light beam. Any necessary shutter cooling means for cooling the absorbing means may then be provided on an inner or outer surface of the apparatus instead of mounting the shutter cooling means on the selector device. Other components on the selector device, such as sensors, such as power meters, etc. may also advantageously be replaced on the selector device 1 with a reflective mirror, directing the light beam towards the specific component positioned in the apparatus instead of on the selector device 1.

In Fig. 3, an apparatus 9 comprising a zoom lens system 21 is shown. The zoom lens system is provided with a motor 22 for changing the spot size on the target area, e.g. according to an input from a user interface, not shown.

In Fig. 4, a zoom lens system 23 is positioned as the output lens of the apparatus 9.

In Figs. 5A and 5B, different treatment patterns are shown. In Fig. 5A, a treatment pattern is provided where a first traversing of the area to be treated is performed using spots 30 having a large spot size, such as a spot size of 8 mm. Afterwards a second traversing is performed using a spot 32 of a small spot size, such as a spot size of 4 mm, so as to fill the holes between the larger spots 30. Alternatively, the top row is traversed using spots 30, whereafter the selector device is turned so that the next row is traversed using two spots 32, whereafter the selector device is turned back so that the next row is traversed using spots 30, etc. This is possible because the selector moving means 14 (shown on Fig 1) is capable of changing the components on the fly during traversing of a pattern without the user noticing any significant increase in the overall time for traversing the target area.

In Fig. 5B another treatment pattern is provided where a first traversing is performed using spots 31 of a large spot size, such as a spot size of 8 mm. The spots have a slight overlap in order to minimise untreated areas. To provide a smooth outline of the treatment area, a second traversing is performed using spots 33 of a smaller spot size, such as spots having a spot size of 4 mm.

It is an advantage of being able to design a treatment pattern comprising more than one spot size that a very uniform treatment pattern may be provided. By, furthermore, using spots of different shapes by providing a diffractive element in the beam path, even more specific treatment patterns may be provided. By e.g. providing a rectangular spot shape, a treatment pattern having substantially no untreated areas between the individual spots may be obtained. The uniformity of the treatment pattern may thus be substantially increased.

Claims

1. An apparatus for tissue treatment comprising:

- means for receiving a first light beam emitted from a first light source, at least two components, each providing a selected focused spot size on a target area, a selector device being movable between at least two positions, each position corresponding to a component, means for moving the selector device between said at least two positions, thereby positioning a selected component in a beam path of the first light beam, the selected component being adapted to emit a second light beam having the selected focused spot size on the target area in response to the first light beam being incident on the component, means for deflecting or directing the second light beam towards the target area, so that the second light beam has the selected focused spot size on the target area.

2. An apparatus to claim 1, wherein at least two of the at least two components comprises lenses having various parameters, said parameters determining the focused spot size of the second light beam on the target area.

3. An apparatus according to any of claims 1 or 2, wherein the selector device comprises a substantially circular disc being movable about an axis of symmetry of the disc.

4. An apparatus according to any of claims 1-3, wherein the selector device comprises an elongated plate being at least substantially linearly movable along a longitudinal axis of the plate.

5. An apparatus according to any of the preceding claims, wherein the light source is a laser device.

6. An apparatus according to claim 5, wherein the laser device is a laser diode.

7. An apparatus according to any of the preceding claims, wherein the means for moving the selector device are electrically controlled.

8. An apparatus according to claim 7, wherein the means for moving the selector device are controlled by a signal from the light source.

9. An apparatus according to any of the preceding claims, wherein the distance between an output of the apparatus and the target area are adjusted according to the selected spot size.

5 10. An apparatus according to any of the preceding claims, wherein the selector device comprises at least three components, at least one of the at least three components being adapted to provide one or more specific functions.

11. An apparatus according to claim 10, wherein the one or more specific functions are 10 selected from a group consisting of sensing, emitting a third light beam, emitting no light beam and emitting a second light beam in response to the first light beam being incident on the selected component.

12. An apparatus according to any of claims 10-11, wherein at least one of the at least 15 three components comprises a zoom lens system for varying the focused spot size of the second light beam.

13. An apparatus according to any of claims 10-12, wherein at least one the at least three components is a sensor providing information about the target area.

20

14. An apparatus according to claim 13, wherein the information provided comprises information about tissue parameters.

15. An apparatus according to claim 14, wherein the tissue parameters are selected from a 25 group consisting of colour, temperature, texture, elasticity, size, shape, reflectivity, and scattering properties.

16. An apparatus according to any of claims 13-15, wherein the sensor is a camera.

30 17. An apparatus according to any of claims 13-16, wherein the information from the sensor is displayed on a display.

18. An apparatus according to any of claims 10-17, wherein at least one of the at least three components is a sensor for measuring beam parameters.

35

19. An apparatus according to claim 18, wherein the sensor measure the power of the first light beam.

20. An apparatus according to any of claims 10-19, wherein at least one of the at least three components provides a shutter function.

21. An apparatus according to claim 20, wherein the shutter is adapted to be operated on 5 the basis of an output produced by a sensor measuring beam parameters of the first light beam.

22. An apparatus according to any of claims 10-21, wherein at least one of the at least three components is a reflecting mirror being adapted to reflect at least a portion of the

10 first light beam.

23. An apparatus according to any of the preceding claims, wherein at least the deflecting means and the selector device are positioned in a handpiece.

15 24. An apparatus according to any of the preceding claims, further comprising deflecting moving means for moving the deflecting means and deflecting control means for controlling the deflecting moving means and being adapted to control the deflecting means so that the second light beam traverses the target area in a predetermined pattern.

20 25. An apparatus according to claim 24, wherein the means for moving the selector device are adapted to change between a number of components being adapted to provide a selected focused spot size of the second light beam on the target area during traversing of the target area and according to the predetermined pattern so that the spot size on the target area are changed during traversing.

25

26. A method of tissue treatment comprising adjusting a focused spot size of a second light beam on a target area, the method comprising

emitting a first light beam from a first light source, 30 - selecting a first focused spot size, moving a selector device between at least two positions, each position corresponding to a component, adjusting the focused spot size by positioning a correspondingly selected component in a beam path of the first light beam, the selected component being adapted to emit a 35 second light beam in response to the first light beam being incident on the selected component, deflecting or emitting the second light beam towards the target area having the selected first focused spot size on the target area, so that the selected component is being adapted to provide the selected first focused spot size of the second light beam on the target area.

27. A method according to claim 26, wherein the first light beam is emitted from a laser 5 device.

28. A method according to claim 27, wherein the first light beam is emitted from a laser diode.

10 29. A method according to any of claims 26-28, wherein the adjusting step comprises positioning a lens in the beam path, the lens having optical parameters corresponding to the first focused spot size.

30. A method according to any of claims 26-29, wherein the movement of the selector 15 device is adjusting step is electrically controlled.

31. A method according to claim 30, wherein a movement control signal is received from the light source.

20 32. A method according to any of claims 26-31, wherein the adjusting step comprises adjusting the distance between an output of the apparatus and the target area.

33. A method according to any of claims 26-32, further comprising the steps of:

25 - selecting a second focused spot size of the second light beam on the target area, adjusting the focused spot size by moving the selector device so as to position a correspondingly selected component in a beam path of the first light beam, the selected component being adapted to emit a second light beam in response to the first iight beam being incident on the selected component,

30 so that the second light beam has the selected second focused spot size on the target area.

34. A method according to any of claims 26-33, further comprising deflecting moving means for moving the deflecting means and deflecting control means for controlling the

35 deflecting moving means and being adapted to control the deflecting means so as to cause the second light beam to traverse the target area according to a predetermined pattern.

35. A method according to claim 34, further comprising the step of selecting more than one focused spot size of the second light beam on the target area and changing the spot size of the second light beam on the target area during traversing of the target area according to the predetermined pattern.

36. A method according to any of claims 26-35, further comprising the steps of:

measuring beam parameters of the first light beam, analysing the measured beam parameters and producing one or more corresponding output, operating a shutter function on the basis of the one or more output, thereby providing or preventing treatment of the target area on the basis of the measured beam parameters.

37. A method according to claim 36, wherein the selecting step is also performed according to the one or more output.

38. A method according to claim 36 or 37, wherein the adjusting step is also performed according to the one or more output.