WO2015114631A1

WO2015114631A1 - Detecting and treating skin surface features

Info

Publication number: WO2015114631A1
Application number: PCT/IL2015/050106
Authority: WO
Inventors: Shimon Mizrahi
Original assignee: Shimon Mizrahi
Priority date: 2014-02-01
Filing date: 2015-01-29
Publication date: 2015-08-06

Abstract

There is provided in accordance with an aspect of the presently discloses subject matter an apparatus for an aesthetic treatment of a feature on a skin surface. The apparatus incudes a light source configured for emitting light for an aesthetic treatment of the feature; a detector for detecting the location 'of the feature with respect to the skin surface; and an optical mechanism for directing the light towards the location thereby treating the feature.

Description

- ί -

DETECTING AND TREATING SKIN SURFACE FEATURES

TECHNOLOGICAL FIELD The presently disclosed subject matter relates an apparatus for treating skin surface in general, and in particular to a light treating apparatus for detecting and treating features on a skin surface.

The term "feature" as used herein shall refer to any skin element, including hair, hair follicles, an immediate area surrounding hair follicles, acne, acne nodule, scars, etc. or any element on the skin surface which ca he treated by light and including the proximate surroundings of the above elements.

BACKGROUND

There are known methods for treating features on a skin surface such as hair, acne etc. According: to some examples, the treatment is carried out by utilizing lights in various wavelength.

WO 2013/19 864 discloses an aesthetic treatment device comprising an illumination system, an imaging device and multiple treatment light sources. The device can include a mechanical guidance system to guide the multiple treatment, light sources. The illumination system includes multiple illumination light sources adapted to irradiate light parallel to a predetermined area of skin.

GENERAL DESCRIPTION

There is provided in accordance with an aspect of the presently discloses subject matter an apparatus for an aesthetic treatment of a feature cm a skin surface. The apparatus incudes a light source configured for emitting light for an aesthetic treatment of the feature; a detector for detecting the location of the feature with respect to the skin surface; and an optical mechanism for directing the light towards the location thereby treating the feature.

The optical mechanism can include a mirror configured to reflect the light from the light source towards the location. The mirror can be configured to be moved such that, the light can be directed to a plurality of locations on the skin surface. The mirror can be moving mirror configured to be moved by a motor in accordance with the location, The mirror can be an oscillating mirror configured to .rotaiionally oscillate and to direct light towards the location at least one time during a cycle of oscillation. The light source can be configured to selectively emit the light and can b configured to emit the light only when tile oscillating mirror is directed towards the location. The oscillating mirror can be mounted on a spring. The optical mechanism can further include an electro-mechanical driver operable to cause the oscillating mirror to rotaiionally oscillate.

Alternatively, the mirror can be a polygon mirror havin a plurality of reflective facets configured to rotate such that during rotation thereof at least one of the facets is configured to reflect the light from the light source towards the location.

The light source can be configured t selectively emi the light and is configured to emit the light only when one of the facets is directed towards the location.

The optical mechanism can include a mechanism for directing the ligh source towards the location.

The detector can include a photosensitive device configured for detecting at least one parameter of the skin surface. The parameter can var between the feature and the surroundings thereof, such that the location can be determined thereby.

The feature can be an area of a hair protruding from a hair follicle in the skin surface. The feature can be an area of an acne nodule.

The apparatus can further include an illumination device configured for illuminating the skin surface. The illumination device can" be selectively configured to illuminate light in two .or more iHuminalion ranges. The illumination range can be selected in accordance with the skin tone characteristics of the skin surface.

The detector can be further configured to detect the skin tone characteristics. The detector can be configured to detect a parameter of the skin surface in accordance the illumination.

There is provided in accordance with a further aspect of the. presently disclosed subject matter a method for determining a location of feature on a skin surface. The method includes scanning the skin surface by a photosensitive device configured to detect a predetermined parameter in each area unit of the skin surface; generating: a matrix of digital values each representing value of the arameter in each of the area units; selecting two or more area matrices each being a portion of the matrix and corresponding to an area of said surface; applying matri multiplication between each of said area matrices and a filter matrix configured such that the sum of products Of said matrix multiplication provides the an absolute value abo ve a predetermined threshold when the area matrix wtresponds to an area having the feature therein; and determining the location of the feature in accordance with the absolute values received b the matrix multiplication.

Each of the area matrices can correspond to an area of the skin surface wherein the area being larger than the area of the feature.

The filter matrix can be configured such that_, the sum of products of the matrix multiplica ion with an area matrix corresponds to an area of the skin surface which does not include the feature therein has a low absolute value in comparison with the sum of products of the matri multiplication with an area matrix corresponding to an area of the surface having the feature therein.

The filter matrix can include filtering values arranged in locations within the filter matrix such that the arrangement thereof corresponds to an arrangement of values of the parameter in the area of the skin surface ¾n which the feature is disposed. The filter matrix can be configured such, thai the sum of products of the matrix multiplication provides the highest absolute value when the area matrix corresponds to an area having the feature disposed at the center thereof. The filter matrix can include filtering Values the sum of which is close to zero with respect to the sum of products thereof with an area matrix having the feature therein, The filter matrix can be configured such that the sum of products thereof with an area matrix corresponding to an area of the skin surface having the feature therein is at least_.10 tiroes the sum of products thereof with an area matrix correspondin to an area of the skin surface which does not include the feature therein.

The parameter can be intensity of light reflected from each of the area units.

The method can further include determining characteristics of the feature b analyzing the value of the sum of product the area matrices. The analysis can include determining whether the value is negative or positive.

The method ca further include detecting an additional parameter of at least the location of the feature, the additional parameter can be configured to assess the characteristics of the feature. The additional parameter can be a color space of the feature. The additional parameter can be detected for all the area unit of the skin surface,

The method can further include illuminating the skin surface with illumination being configured to be absorbed by the feature, The illumination can be configured in accordance the skin tone characteristics of the ski surface, such an intensity of the feature is different than the intensity of the rest of the skin surface. The feature can be at least a portion of hair. The feature can be at least a portion of an acne^' nodule. The feature can be a skin disorder.

The step of applying matrix inultiplication can be carried out a plurality of filter matrices each being configured to detect a predetermined feature on the; skin surface. The plurality of filter can include at least a filter configured to detect a mole on the skin surface, a filter matrix configured to detect an acne nodule, and a filter matrix configured to detect hair. The plurality of filter can include a filter configured to detect a feature on a dark skin and a filter configured to detect a feature on a light skin.

The method can further include selecting a filter matrix in accordance with the skin tone of the skin surface.

There i further provided in accordance with yet another aspect of the presently discloses subject matter an apparatus for detecting a feature on skin surface, the apparatus comprising a detector configured for detecting a predetermined parameter in each area unit of the skin surface; a controller configured for generating a matrix of digital values each representing a value of the parameter in each of the area units; selecting two or more area matrices each being a portion of the matrix- .-and^' corresponding to an area of the surface; applying matrix multiplication between each of the area matrices and a filter matrix configured such that the sum of products of the matrix inultiplication provides the an absolute value above a predetermined threshold when the area matrix corresponds to an area having the feature therein; and determining the location of the feature in accordance with the absolute values received by the matrix multiplication.

BRIEF DESCRIPTION OF THE DRAWINGS

in order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non- limiting example only, with reference to the accompanying drawings, in which:

Fig.- 1 A is a perspective view of an apparatus for treating skin surface, in accordance with an example of the presently disclosed subject matter;

Fig. IB is an exploded view of the apparatus of Fig. 1A;

Fig, 2 A is a front perspective view of the inner portion of the apparatus of Fig, I A;

Fig. 2B is a back perspective view of the inner portion of the apparatus of Fig. 1 A;

'Fig. 2C is a top view of the inner portion of the apparatus of Fig. 1 A, disposed in close proximity to a skin surface; Fig. 3 is a perspective view of an inner portion of an apparatus for treating skin surface, in accordance with another example of the presently disclosed subject matter;

Fig. 4 A is a top view of a skin surface having a plurality of hair therein;

Fig 4B is a schematic illustration of a matrix representing a segment of the skin surface 5 of Fig. 4A, and a filter matrix configured to detect hair in accordance with an example of the presently disclosed subject matter applied on a first area of the matrix;

Pig 4C i a schematic illustration of the matrix of Fig. 4A wherein the filter matrix applied on a second area of the matrix;

Fig 5A is a schematic illustration of the matrix of Fig. 4 A wherein the filter matri i o applied on a furth e area of the matri ;

Fig SB is a schematic illustration of the matrix of Fig. 4A wherein the filter matrix applied on a area of the matri corresponding to a first area of a skin surface having an hair therein;

Fig SC is a schematic illustration of the matrix of Fig, 4A wherein the filter matrix 1.5 applied on a are of the matrix, corresponding to a second area, of skin surface having an hair therein;

Fig. 6A is a top view of a skin surface h a ving acne therein;

Fig 6B is a schematic illustration of a filter matrix configured to detect acne in accordance with an example of the presently disclosed subject matter; and

0 Fig 6C is a schematic illustration of filter matrix configured to detect acne in accordance with an example of the presently disclosed subject matter.

DETAILED DESCRIPTION OF EMBODIMENTS

Figs. IA through 2B show an apparatus 10 for an aesthetic treatment of a feature on a skin surface. The apparatus 10 includes a housing 12 having a transmitting portion 14 configured for allowing light to be transmitted therethrough. The transmitting portion 14 can be an aperture, a portion made of a transparent or translucent martial such that light can be transmitted therethrough. The housing 12 can be made with an ergonomic shape such can be held and self- operated by a user.

The apparatus- 10 further includes a light source 20 configured for emitting light for an aesthetic treatment of a feature of a skin surface. The light source 20 can be any fight emitting device such as laser, laser diode, high power LED, etc. and can be configured to. provide an aesthetic treatment of a skin feature, for instance for treating hair, treating acne of other skin disorders, as well as various skin conditions as wrinkles, sears, etc,

The apparatus 10 further includes a detector 30 configured for detecting the location of the feature with respect t the skin surface, such that the light emitted from the light source 20 can be directed to the location of the feature. The detector 30 can include a photosensiti ve device configured for detecting at least one paramete of the skin surface, such as intensit of Sight reflected therefrom, the wavelength range of the light reflected from, the skin surface, and from the feature, to be treated, or the distance between the detector and the skin surface or the feature thereon. The detecto is thus configured to detect th exact location of the feature to be treated, for example the location of the hair to be removed, it is appreciated that the parameter detected by the detector 30 can be such which varies between the feature and the surroundings thereof, such that the location of the feature can be determined by the detect ed parameter,. That is to say. if the detector is configured to detect the intensity of light reflected from the skin surface, the detector is thus configured to detect the difference between, the intensity of light reflected from_. the feature, such as the hair and the light reflected from the skin surface around: the hair.

It will be appreciated that- in the latter example, the immediate surroundings of the hair can be considered as part of the feature to be detected, as: the light reflected from the skin surrounding the follicle may have different intensity that the light reflected from areas on the skin surface relatively distanced from the follicle.

The apparatus^' 1:0 further includes an optical mechanism for directing the light towards the location of the Feature so as to provide the required treatments thereto, The optical mechanism can include a mirror ^'34 configured to reflect the light emitted from the li ht source 20 towards the location of the detected feature, The mirror can he any known, mirror configured to reflect the light emitted from the light source 20 or a portion thereof. The mirror 34 can be configured to be moved such that the; light reflected thereon can be directed to any desired location on the skin surface. For example, the mirror 34 can. be a moving mirror configured to be moved by a motor in accordance with the location t which the light is directed.

According to _.the -illustrated example, the mirror 34 is an oscillating mirror configured to roiationally oscillate, such that the mirror scans the skin surface in repeated cycles. It is appreciated that the angular -displacement of the ·^'■ mirror can be configured such that it ca direct light towards any desired location, on the skin surface- at least one time during a cycle of oscillation. It will be appreciated that the skin surface, for this^' matter, can be only a portion of the skin surface, for example the skin surface which is directed to through the transmitting portion 14 of the housing 12. Accordingly, the are of the skin surface which can be treated depends on the dimensions of the transmitting portion 14, and the disposition of the. mirror 34 with respect thereto.

According to an example, the light source 20 can be configured to selectively emit light onl when the oscillating mirror 34 is directed towards the location of the feature to be treated. This way, the light source 20 can. be configured to emit light onl towards the feature to be treated. Accordingly, the light source 20 can be configured with a relatively high energy light pulse, and can be configured to preclude unnecessary damage to the ski surface on which there is no feature to be treated. It is further noted that the apparatus 1 can thus be configured such that energy consumption of the light source 20 is reduced by activating the light source 20 only whe the oscillating mirro 34 is directed towards the location of the feature.

According to an example oscillating mirror 3 can be mounted on a spring providing, an oscillating movement or, as in the illustrated example, can be coupled to an electro-mechanical driver 36 operable to cause the oscillating mirror 34 to rotationally oscillate. The electro- mechanical driver 36 can be an electro magnet or a piezoelectric element.

It is appreciated that the optical mechanism can include a collimator 24 such that the direction of the light is aligned in a specific direction or that, the spatial cross section of the light beam emitted from the light source 20 is smaller,.

It is further appreciated that the light source can be laser providing a high energy light on an are unit, such that the desired treatment can be provided to a specific feature on an area unit, without affecting the surroundings of the treated feature. .Alternatively, the optical mechanism can include one or more lenses configured for focusing the light beam emitted from the light source 20, this way, the light source can be a light emitting diode configured to emit through a such that the beam has a smaller cross section and the energy of the li ght beam is concentrated to a smaller area unit facilitating treating a specific area unit without effecting the surroundings thereof

The apparatus 10 can further includes an illumination device, such as one or more LEDs 38 configured for illuminating the skin surface, such that the parameter detected by the detector can be better detected. That is to say, if the detector 30 is configured, to detect intensity of light reflected from each area unit of the skin surface, the LEDs 38 can be configured to illuminate the skin surface, or at least a portion of the skin surface which i accessible through the transmitting portion. 14 and which is thus examined by the detector. The LEDs 38, according to the present example, are evenly disposed around the detector 30 such that the entire skin surface area under treatment is illuminated and the light, reflected by the skin surface can thus he detected by the detector.

The illumination device can further include an auxiliary light source 4 for providing a horizontal illumination with respect to the skin surface. The auxiliary light source 4Θ can be one or more LEDs disposed at the opening of the transmitting portion 14 and directed for a lateral illumination of the ski surface. The auxiliar light source 40 can be utilized for side illumination of features ^'protruding from the skin surface, such as hair, acne, etc. thus precluding shades caused thereby which may affect the parameter detected by the detector 30.

The illumination device can be configured for illuminatio of light having properties corresponding to the properties of the detector 30. That is to say, if the detector is -configured to detect light in ^'the IR range, the illuminatio device -can be configured to. illuminate IR light on the skin surface, thus allowing the detector to detect the IR light reflected from the skin surface, and to detect the difference between parameters of the IR light reflected from a feature on the skin surface and parameters, of the IR light reflected from, the surroundings, thereof

The illumination device, according to. an example, can be selectively configured to illuminate ligh in tw or more illumination, ranges. The illumination range can be selected in accordance with the skin tone characteristics of the skin surface, so as to optimize the detection of features thereon. For example, for a dark skin a first illumination can be selected and for a light skm a second illumination can be selected. In addition, the illumination can be selected in accordance with the feature to be detected, for instance, for detecting dark hair a first illuminatio can be selected while for detecting a light hair a second illumination can be selected. Accordingly, the apparatus can be used for detecting a vari ety of features and features on a variety of skin surfaces,

It is appreciated that in order to allow an automatic selection of the illumination the detector can configured to detect the skin tone characteristics of the skin surface._. That is to say, the detector can be configured to first detect, the color of the skin, or other characteristics thereof as well s characteristics of the feature, such as the color of the hair. In this example, in accordance with the color of the skin and the color of the hair the illumination is selected, for^' example IR light can be selected for a dark skin, etc.

Alternatively, a second detector can be provided for detecting the skin tone characteristic of the skin surface, and the characteristics of the feature to be detected. According to an example, the apparatus: 10 cars further include one or more calibration detectors 42 configured for calibration of the mirror 34, such that the disposition of the mirror with respect to the location of the feature to be treated can be set. The calibration detectors 42 can he disposed on two sides of the .transmitting portion 14, for example, on the side posts 43 at the edges of the transmitting portion 14, suc that when the oscillating mirror 34 i s disposed such thai light is directed to the edge of the transmitting portion 14 the calibration detectors 42 can detect the light reflected. This way the field of vision of the oscillating- -mirror 34 can be deterrnmed, and the ratio between the angular displacement of the mirror 34 and the location of the feature within the field of vision can be determined.

The apparatus can further includes a designated microcontroller 44 such as Aim Cortex

M4, FPGA or ASIC which can be configured to calculate the location of the feature to be treated with respect to the mirror 34, The microcontroller 44 can be further configured to determine the illumination range of the illumination device in accordance^' with the characteristics of the skin, such as the skin tone and the features to be treated. In addition the microcontroller 44 can be configured to determine the properties of the fight beam emitted from the light source 20 in accordance with the feature to be treated.

As shown in Fig. 2C, the operation of the apparatus can be as follows: the apparatus is disposed in close proximity to the skin -surface 50, having a plurality of hair 52 to be removed. The detector 30 detects a parameter of each are unit of the skin surface, such as intensity and/or color of the light reflected therefrom, and detects the difference between values of the parameters received in area units in which the hair 52 is disposed. The microcontroller 44 determines the location of the hair with respect to the portion of the skin surface which is visible to the detector 30 and to the mirror 34 through the transmitting portion 14, The optical mechanism directs the fight beam emitted from the Sight source towards the hair 52 to be treated. According to the illustrated example the oscillating, mirror 34 is repeatedly rotated to scan the portion of the skin surface- visible through the transmitting portion 14, i.e. the area between the calibration detectors 42. When the oscillating mirror 34 is disposed facing the location of the detected hair 52, the light source .20 is actuated and the light beam is emitted towards the oscillating mirror 34 and further to the location of the hair 52.

Attention is now made to Fig. 3, an apparatus 60, according to another example, is shown wherein like nuraerais have been employed to designate similar parts. The apparatus 60, includes a light source 20, an illumination device in the form of a plurality of LEDs- 38, a detector 30 and an optical mechanism configured to direct a light beam emitted from the light source 20 towards - 30 - the feature to be treated. The optical mechanism according to the present example includes a collimator 24, or a lens in a ease of a LED light source, configured to. direct the light beam from the light source 20 towards a polygon mirror 6 having a plurality of reflective facets 65, The polygon mirror 62 is configured to rotate such that during rotation thereof at least one of the facets 65 is disposed such that light directed thereon from the light source 20 is reflected towards the location of the feature to he treated. The polygon mirror 62 can be provided with a motor (not shown) for the rotation thereof, such that the during the operation of the apparatus, the polygon mirror 62 is rotated such that during each cycle of rotation each of the facets 65 scans the entire skin surface visible through the transmitting portion 14. That is to say, each of the facets 65 is rotationafly displaced togethe with the mirror 62 such that each facet has a scanning cycle during the period of rotation of the polygon mirror 62 when that facet 65 faces the transmitting portion.14.

Accordingly, during the scanning cycle of each facet 65, the facet faces the first post 43 disposed on one end of the transmitting portion 14, at the beginning of the scanning cycle and faces the second post 43 disposed on an opposite end of the transmitting portion 14, at the end of the scanning cycle. Accordingly, at any given point during the operation of the apparatus 6Θ at least one of the facets 65 faces a portion of the skin surface. As noted herein above with regards to the previous example, the light source 20 can be configured to selectively emit light only when one of the facets 65 of the polygon miiror 62 is directed towards the location of the feature to be treated.

Accordin to a further exanipie, the an optical device configured to selectively direct: light in various directions such as_. a digital micromirror device (known as DMD) such that the light directed thereon from the light source 20 can be directed towards the desired location on the skin surface.

In addition, the mirror can be a convex miiror such that light directed thereto is focused to a specific location on the skin surface.

It is appreciated that according to a further example the optical mechanism can include a. mechanism for directing the light source itself towards the location of the feature to be treated, with or without a reflecting mirror,

According to an example, detection of the location of a feature on the skin surface can be carried out by first forming a virtual image of the skin surface showing the detected parameter i each area unit of the skin surface. For example an image can be formed showing the intensity of each area unit on the skin surface, the area unit, thus can be represented as a pixel in the image, It W

- I I - is appreciated that there is no requirement for generating and displaying an actual image, rather the, so called, image can be arranged in a matrix of digital values each representing a value of the parameter in each of the area units of the skin surface. For example, the matrix can be an array of values each being the value of the intensity of the light reflected from each area unit. In the present case each area unit can be the typical size of the feature to be detected, which in the case of hair can a square millimeter or less. As the skin surface is never homogenous the matrix includes a variety of values, each representing, for example, the intensity of a single area unit

Once the matri is generated, it is desired to analyze the values so as to differentiate between various features on the skin surface. For instance, the intensity of light reflected from an area unit including a stain, may be the same as that which is reflected form an area unit having an hair. Thus, it is required to provide a further step of analy zing the values in the matrix.

According to an aspect of the presently disclosed subject matter, analyzing the values is carried out by applying a filter matrix to portions of the matrix. That is to say, a section of the matrix corresponding to a portion of the skin surface can be selected. For the sake of simplicity, the selected section of the matrix is defined hereinafter as an area matrix.

The filter matrix can he a matrix filtering value arranged such that, when matrix multiplicatio between the filter matrix and the area matrix is applied, the feature is detected. According to an example, the filter is configured such that the sum of products of the matrix multiplication provides the an absolute value above a predetermined threshold when the area matrix corresponds to an area having the feature therein. The threshold can be determined in accordance with the absolute value received by matrix multiplication of other area matrices of the matrix, i.e. area matrices corresponding to areas on the skin surface which do not include the feature therein.

Fig. 4A shows a skin surface 70 having a plurality of hair 72 protruding from a hair follicle 74. As shown in Fig. 4B, the skin surface, or a portion thereof can be represented by a matrix 80 including a plurality of values 82 each representing a parameter of a unit area of the skin surface- 70, such as intensity of light reflected therefrom. It is appreciated that the intensity of light reflected from area units including hair therein may be lower in case the hair is a dark hair, as the hair absorbs a large amount of the light impinging. hereon. It. thus expected feat the value in the matrix 80, corresponding to an area unit having hair therein, will be lower than other areas, it is however difficult to locate the hair as other areas on the skin surface 70 might have the same level of light absorption, such as stains etc. Thus, it is required that the portions of the matri 80 corresponding to area of the skin surface at the center of which the hair is located will he detected.

Accordingly, in order to allow detection of the hair 72 a dedicated filter matrix 96, shown in Fig. 4B, configured to detect hair on a skin surface, can be applied. As explained here in above, the matrix 80 representing a parameter, such as intensity, o each area unit of the skin surface 70 is ge erated. The filte matrix 90 is then applied on a area matrix, i.e. a segment o the matrix 80 representing a porti on of the skin surface 70.

The area matrix, as well as the filter matrix 90 can have dimensions corresponding to a portion of the skin surface 70, which has a larger area than the area of the feature. In the current example, the feature ca be each one of the hair 72 as well as its immediate surroundings, this is due t the face that the intensity of th light reflected from the immediate surroundings of the hai follicle 74 is different^' than that which is reflected form othe areas of the skin surface 70.

As shown in Fig. 4B, the filter matrix 90 includes a plurality of values 92, the sum of which is zero, such that whe the filter matrix 90 is multiplied with an area matrix having homogenous values, the sum of products is zero as well.

Accordingly, when the area matrix corresponds to a portion of the skin surface which ail the area: units therein reflect light having the same or similar intensity, the values in the area matrix are identical or close to one another. Thus, when the filter matrix 90 is applied on area matrix of such an area the sum of product thereof is zero or close to zero.

As further shown in Fig. 4B, the filtering values 92 in the filter matrix 90 can b arranged in locations therein such that the arrangement thereof corresponds to the expected values of the detected parameter in the portio of the skin surface which includes the feature to be detected. That is to say, in the present example, the root of the hair 72 provides a low intensity value due to the high absorbent thereof, the immediate surroundings f the hair follicle 74, provides a medium intensity value, while the rest of the area provides a high intensity value relative to the root of the hair.

Accordingly, the filter matri 90 includes values 92 arranged such, that the middle value is the extreme value of 32. corresponding to the intensity of light reflected by the root of hair, the surroundings values thereof are 8, corresponding to the intensit of light reflected by the surroundings of the hair follicle 74. and the values at the circumference of the matrix are the low val ues of -6, corresponding to the in tensity of light reflected by the rest of the area.

Accordingly, the filter matri can be applied on a plurality of area matrices, each representing a portion of the skin surface. When the filter matrix .90 is applied on an area matrix corresponding to an area of the skin surface 70, which is fairly h mongous the sum of products is zero or close to zero as the area matrix includes values which are substantially identical while the sum of the filtering values 92 of the filter matrix 90 is 0,

When the filter matrix 90 is, however, applied on an area matrix corresponding to an area of the skin surface 70, which includes a hair 72 at the center thereof, the sum of products is far from zero as the area matrix includes values which are gradually increasing from the circumference thereof towards the cente thereof, corresponding to the arrangement of the f ltering values 92 while the sum of the filtering values 92 of the filter matrix 90 is zero.

it is appreciated that the matri 80 of the entire skin surface 70 can be evaluated by applying the filter matrix 9Θ on various segments thereof According to the example illustrated in Fig. 4A, the filter matrix 90 is first applied on a first area matrix 84a on the top left corner of the matrix 80, following which it is applied on a second area matrix 84b which is disposed on the top of the matrix 80 and starting form one cell away from the right comer, as shown in Fig. 4C. The filter matrix 90 can thus be shifted, to the right one cell at a time such that it is applied many times on. all the area matrices along the width of the matrix, until it is applied on the entire width, of the matrix 80 representing the skin surface 70. As the filter matrix 90 reaches the top left corner of the matrix 80, it can be shifted one ceil down such that it can now be applied on the entire width of the matrix 80 however one cell shifted, down. This way, the filter matrix 90 can be appli ed on all the possible area matrices of the skin surface 70.

it is appreciated that since the filter matrix 90 is shifted only one cell at a time, the area matrices on which it is applied partially overlap one another. Thus, the area matrices, here designated 86a and. S6bin which the feature is located precisely at the center thereof can he detected.

As noted hereinabove, applying the filter matrix involves carrying out matrix multiplication, and calculating the sum of products thereof Thus, applying the filter matri ..90 on many area matrices yields a series of results each representing the sum of product, of one matrix area. For example, when the filter matrix 9 is applied _.on, the area matri 84a, the result is -380. Similarly, as shown in Fig. 5 A, when the filter matrix 90 is applied on the area matrix 84c, the result is 1280, When the filter matrix 90 is however applied on the area matrix 86a representing an area of the skin surface 70 at the center of which the hair 72 is located, the result i -3932, as shown in Fig. 5B. Similarly, as shown in Fig, 5C, when the filter matri 90 is applied on the area matrix 86b, the result is -4184. It should be noted that the absolute value of the matrix multiplication between the filter matrix 90 and the area matrix 84c of Fig. 5A, is relatively high since it partially overlaps with the area matrix 86a. Thai is to say, the area matrix 84c corresponds to an area of the skin surface 70 having a portion of the feature therein, -or having the feature therein however not at the center thereof. Thus, the results having an absolute value above a certain threshold can be utilized to determine the area matrix corresponding to an area of 5 the skin surface in which hair is located. Since the filter matrix 90, of the present example, is designed to detect a hair located at the center of the area matrix, the location of the hair can be assumed to be at the location corresponding to the center of the area matrix which, yielded the highes absolute value. In the illustrated example this area is the area representin by the matri area 86s, having the value 58 at the center thereof, which represents the location of the hair i O follicle. Similarly, the matrix area 86b, having the value SO at the center thereof representing the location of another hair follicle.

The filter matrix 90 can be configured such that the sum of products of the matrix multiplication with an area matrix., corresponding to an area of the skin surface which does not include hair has a low absolute value in comparison with the sum of products of the matrix

1.5 multiplication with an area matrix corresponding to an area of the ski surface which includes hair therein.

It should be understood that according to the present example the filter matrix 90 is designed to detect the difference between the parameter of feature and that of the surroundings thereof. Thus, each of the area matrices on which the filter matrix is applied corresponds to an20 area of the skin surface which is larger than the area of the feature t be detected. This way, the filter matrix applied thereon can be arranged with values -corresponding to the characteristics of the feature and the surroundings thereof.

It is appreciated that although according to the present example the filter matrix is designed to detect the area matrix at the center of which the feature is disposed, according to 5 other examples, the filter matrix can be designed to detect the area matrix in which the feature is disposed, regardless to the location thereof within the area matrix.

Although in the example of Figs. 46 through SC the filter matrix includes filtering values, the sum of which is 0, according to other examples the filtering values the sum of which is close to zero relative to the sum of products .received- when the filter is applied to a matrix. are

30 in which the feature is located. For example, if the filter matrix is configured such that when applied on an area matrix which corresponds to an area having hair therein, the result is at least 10 times the value which is received when the filter matrix is applied on an area matrix which corresponds to an area without hair therein. Accordingly, the sum of the filtering values is configured such that it is close to zero with respect to the sum of products thereof with an area matrix having the hair therein.

According to an exam le, a further analysis or filter may be carried out in order to assess the feature detected b the filter matrix. For exaiftple, as explained hereinabove, the area matrix corresponding to the area of the skin surface having: the feature therein is detected by determining which of the area matrices provides the an absolute value above a predetermined threshold when the filter matrix is applied thereon. However, since sometimes the absolute value may exceed the predetermined threshold when the filter matri is applied on an ^: area. having a feature sirailar to the feature which it is desired to detect. For instance, if the filter matrix is designed to detect a dark hair the skin surface, the matrix multiplication ma yield a high value when applied on an area matrix having a light dot thereon, such as a gleaming point. In the example of the filter matrix 90 of Fig. 4B, however, will yield a relatively high positive value when detecting a light dot, as oppose to a high negative value when: detecting a root of hair. Thus, once the area matrix having a high absolute value is detected, the further analysis can be assessing whether the value is a positive value or a..negative one,

According to another example, the ^'filter matrix 90 of Fig. 4B may locate a red area on the skin surface which might yield a sum of product above the predetermined threshold. Thus, in order to ensure that the detected atrix area includes hair, a further analysis can be applied. For example, the detector can be configured to provide an additional parameter according to which the existence of the feature can be verified. According to a example, the additional parameter can be related to the color of each area unit. For instance, the detecto can be configured to provide the YCb^'Cr of each area unit, that providing. both the intensity and the color space of each area unit. The color space of the area unit in which a high sum of product is received, can be analyzed so as to verify that feature therein is the feature to be treated.

According to an example, the YCbCr data can be converted to other the^' color space such as RGB, MS V or normalized G.

According to an exampie the apparatus can include a plurality of filter matrices each being configured to detect a predetermined feature on the skin surface. The apparatus can be configured to selectively apply the desired filter. For example, the apparatus can first be configured to apply a filter matrix configured to detect a mole on the skin surface, then t apply a filter matrix configured to detect an acne nodule, and only then to apply a fiiter matrix configured to detect hair on the skin surface. This way, the location of a mole is not erroneously is as a location of hair, etc. In addition, detecting hair located inside a mole might require W 201

- 16 - utilixing a different filter matrix, than for detecting hair disposed around regular skin area. Thus, first detecting location of moles and acne nodule on the skin surface can facilitate detecting hair located at any location of the skin surface.

it should be further appreciated that the filter matrix can be 'further selected in accordance with the illumination utilized for illuminating the skin surface. That is to say, the apparatus can include a first filter matrix to be applied when visible tight is utilized and a second filter to be applied when IR light is utilized. As indicated hereinabove selecting the desired illumination can be carried out can by a detector configured to detect the skin tone of the skin surface or other characteristics thereof, as well as the characteristics of the feature to be detected.

Reference is now made to Fig. 6A a skin surface 100 having acne 102 can. he treated by a

•light treating apparatus, such as described herein above with respect to Figs. 1A to 3. In order to allo detection of each acne nodule 102 a dedicated filter matrix 110, shown in Fig. 6B, can be applied. As explained here in above, a matrix representing a parameter, such as intensity, of each area unit of the skin surface 110 is generated. The filter matrix 110 is then applied on an area matrix, i-e, a segment of the matrix representing a portion of the skin surface 110.

The area matrix, as well as the fitter matrix 1 10 can have dimensions corresponding to a portion of the ski surface 110, which has a larger area than the area of each acne nodule, as well as its immediate surroundings. It should be noted that the dimensions of the filter matrix for detecting acne is larger than that for detecting hair, as shown in Fig. 4B. Thi is due to the fact that the acne nodule and its surroundings dispose on larger area, than a hair.

As shown in Fig. 6B, the filter matrix 10 includes a plurality of values 112, the sum of which is- zero, such thai when the filter matrix 110 is multiplied with an area matrix having homogenous values, the sum of products is zero as well.

As further show in Fig. 6B, the filtering value 112 in the filter matrix 1.10 are arranged in locations therein such that the arrangement thereof corresponds- to the expected values of the detected parameter in the portion of the skin surface which includes the acne 102. Thai is to say, in the present example, the center of the acne 102 a light skin 104 having a -dark, point 105 therein, the light skin 104 is surrounded by a red skin portion 106, which is surrounded by a regular healthy skin.

Accordingly, the filter matrix 110 includes filtering values 112 arranged such mat the middle value is the value of 8, corresponding to the intensity of light reflected by the dark point 105, the surroundings- values thereof are 16, corresponding to the intensity of light reflected by the light skin 104 surroundings of the dark point 1.05. Similarly, the surroundings values are -30 representing red skin portion .106 and the values at the - circumference of the matrix are the values of 1. corresponding to the intensity pf light reflected by the healthy skin around the acne.

Accordingly, when the filter matrix .1,10 is applied on an area matrix corresponding to an area. of the skin surface 1.10, which includes acne 1.02 at the center thereof the sum of products is far f om zero as the area matrix includes values corresponding to the arrangement of the filtering values 112 while t e sum of the filtering values 92 of the filter matrix 90 is zero,

Fig. 6C shows another example of a. filter -matrix .120 having a plurality of filtering values 122. The filter matrix 120 is configured to detect an acne having an elongated shape, as opposed to a rounded shape. Thus, the filtering values 122 are not arranged in ^'circular order, as in the example of Fig. 6B, rather the values are arranged in an elongated order corresponding to various element in an elongated acne nodule.

Those skilled in the art to which the presently disclosed subject matter pertains will readil appreciate that numerous changes, variations, and modifications can be made without departing from the scope of the invention, mi atL miuandis,

Claims

1. An apparatus for an aesthetic treatment of a feature on a skin surface, tire apparatus comprising:

a light source configured for emitting light for an aesthetic treatment of the feature;

a detector for detecting the location of the feature with respect to said skin surface; and an optical .mechanism -for directing said light towards said, location thereby treating said feature,

2, The apparatus accordin to claim 1 wherein said optical mechanism comprises mirror configured to reflect said light, from said light source towards said location.

3, The appar us according to claim 2 wherein said mirror is configured to be moved such that said light can be directed to a pluraiity of locations on said skin surface.

The apparatus according to claim 3 wherein said mirror is a moving mirror configured to be moved by a motor in accordance with said location.

5. The apparatus according to claim 3 wherein said mirror is an oscillating mirror configured to rotationally oscillate and to direct light towards said location at least one time during a cycle of oscillation.

61, The apparatus according to claim 5 wherein said light source is configured to selectively emit said light and is configured to emit said light only when said oscillating mirror is directed towards said location.

7. The apparatus according: to any one of claims 5 and 6 wherein said oscillating mirror is mounted on a spring.

8, The apparatus according to any one of claims 5 to 7 wherein said optical mechanism further comprises an electro-mechanical driver operable to cause said oscillating mirror to rotationally oscillate.

9. The apparatus according to claim 3 wherein said mirror is a polygon mirror having a plurality of .reflective facets configured to rotate such that during rotation thereof at least one of said facets is configured to reflect, said light from said light source towards said location,

10, The apparatus according to claim 9 wherein said light source is configured to selectively emit said light and is configured to emit said light only when one of said facets is directed towards said location.

11. The apparatus according to claim I wherein said optical mechanism comprises a mechanism for directing said light source towards said location.

12. The apparatus according to claim 1 wherein- said detector includes a photosensitive device con figured for detecting at least one parameter of the skin surface.

.1.3. The apparatus according to claim 12 wherein said -parameter varies between the feature and the surroundings thereof, such that said location can be . determined thereby,

5 14, The apparatus- according to an one of claims 1 to 13 wherein the feature is an area of a hair protruding from a hair follicle in said skin surface.

15. The apparatus according to any ne of claims 1 to 13 wherein the feature is an area of an acne nodule.

16. The apparatus according to Claim 1 further comprises an illumination device configured 10 for illuminating the skin surface,

17. The apparatus according to_. Claim 16 wherein said illumination device is selectively configured to illuminate light in two of more illumination ranges.

18. The apparatus according to Claim 1.7 -wherein said illumination range is .selected in accordance with the skin tone characteristics of said skin surface.

15 1 , The apparatus according to claim 1 7 wherein said detector is further conf gured to detect said skin tone characteristics.

20. The apparatus according t any one of claims 1.6 to 1 wherein said detector is configured to detect a parameter of said skin surface in accordance said illumination.

21» A method for determining a location of feature on a skin surface, the method comprising: o scanning the skin surface by a photosensitive device configured to detect a predetennined parameter in each area unit of said skin surface;

generating a matrix of digital values each representing a value of said parameter in each of said area units;

selecting two or more area matrices each being a portion of said matrix and 2-5. corresponding to an area of said surface;

applying matrix multiplication between each of said area matrices and a filter matrix configured such that the sum of products of said matri multiplication provides the an absolute value above a predetennined threshold when the area matri corresponds to an area having the feature therein; and, determining the location of the feature in accordance with the absolute 30 values received by said matri multiplication.

22_* The method according to claim 21 wherein each of said area matrices corresponds to an area; of said skin surface wherein said area being larger than the area of the feature.

23. The method according to any one of claims 21 to 22 wherein said filter matrix is configured such that the sum of products of said matrix multiplication with an area matrix corresponds to m area of said skin surface which does not include said feature therein has a low absolute value in comparison with the sum of products of said matrix multiplication - with an area

5 matri corresponding to an area of said surface having said feature therein,

24. The method according to any one of claims 21 to 23 wherein said filter matri includes filtering values arranged in locations within said filter matrix suc that the arrangement thereof corresponds to an arrangement of values of said parameter in the area of said skin surface in which the feature is disposed.

10 25. The method according to any one of claims 21 to 24 wherein said filter matrix is configured such that the sum of products of said matrix multiplication provides the highest absolute value when the area matrix corresponds to. an area having the feature disposed at the center thereof,

26. The method according to any one of claims 21 to 25 wherein said filter matrix includes 1 5 filtering values the sum of which, is close to zero with respect to the sum of product thereof with an area matrix having said feature therein.

27. The method according to any one of .claims 21 to 26 wherein said, filter matrix is configured such that the sum of products thereof with an area matrix corresponding to an area of said skin surface having said feature therein is at least 10 times the sum of products thereof with

20 an area matri corresponding to an area of said ski surface which does not include said feature therein,

28. The method according to any one of claims 21^' to 28 wherein said parameter is intensit of light reflected from each of said area units.

25 29. The method according to any one of claims 21 to 28 further comprising determining characteristics of the feature by analyzing the value of said sum of product said area matrices.

30. The method according to claim 29 wherein said analysis includes determining whether the value is negative or positive.

31, The method according to any one of claims 21 to 30 further comprising detecting an 30 additional parameter of at least said location of the feature, said additional paraineier being configured to assess the characteristics of the feature.

32_* The method according to claim 31 wherei said additional parameter is a color space of said feature.

33 , The method according to claim 31 wherein said additional parameter is detected for all the area units of said skin surface.

34. The method according to an one of claims 21 to 33 further comprising illuminating said skin surface with illumination being configured to be absorbed by said feature.

5 35. The method according to claim 3.0 wherein said illumination is configured in accordance the skin tone characteristics of said skin surface,: such an intensity of said feature is different than the intensity of the rest of the skin surface,

36. The method according t any one of claims 21 to 35 wherein said feature is at least a portion of hair.

10 37, The method according to any one of claims 21 to 35 wherein said feature is at least a portion of an acne nodule.

3.8.. The method according to any one of claims 21 to 35 wherein said feature is a skin disorder.

39. The method according to any one of claims 21 to 38 wherein said step of applying matrix is multiplication is carried out a plurality of filter matrices each being configured to detect, a predetermined feature o the skin surface.

40. The method according to claim 39 wherein said plurality of filter includes at least a filter configured to detect a mole on the skin surface, a filter matrix configured to detect an acne nodule, and a filter matrix configured to detect hair.

20 4i . The method according to claim 39 - wherein said plurality- of filter includes a filter configured to detect a feature on a dark skin and a filter configured to detect a feature on a light skin,

42. The method according to claim 21 to 37 further comprising selecting a filter matrix in accordance with the skin tone of said skin-surfaoe.

25 43. An apparatus for detecting a feature on a skin surface, the apparatus comprising:

a detector configured for detecting a predetermined parameter in each area unit of the skin surface; arid

a controller configured for generating a matrix of digital values each representing a value of said parameter in each of the area units; selecting two or more area matrices each being a 30 portion of the matrix and corresponding to an area of the surface; applying matrix multiplication between each of said area matrices and a filter matrix configured such that the sum of products of. said matrix multiplication provides the an absolute value above a predetermined threshold when the area -matrix corresponds to an area having the feature therein; and determining the - 99„

location of the feature in accordance, with the absolute values received by the matrix multiplication.