MXPA00012429A - Hair-removing device with a controllable laser source - Google Patents

Abstract

A hair-removing device (1) comprises a laser source (3), an adjustable laser beam manipulator (5) for positioning a laser beam (7) of the laser source (3) in a target position (9) on a skin (11) to be treated, and an image sensor (47) for detecting an image (49) of the skin. According to the invention, the hair-removing device further comprises a control unit (17) which determines a position and orientation on the skin of a hair (13) to be removed, and which determines the target position of the laser beam as a function of said position and orientation of the hair. The control unit brings the laser beam manipulator in a state corresponding to the target position of the laser beam, and activates the laser source when the laser beam manipulator has reached said state. Thus, the hair-removing device is suitable for use by inexperienced users, and is particularly suitable for the consumer market. In a particular embodiment, the control unit determines the target position of the laser beam in a position (71) on the skin under which a root (15) of the hair is present, so that the root of the hair is destroyed and the hair-removing device (1) is an epilating device by means of which the hair is removed for a relatively long time or even permanently. In another embodiment, the control unit determines the target postion of the laser beam in a position (65) on the hair where the hair comes out of the skin, so that the hair is burnt through near the skin surface and the hair-removing device (1") is a shaving device by means of which a high skin smoothness is obtained.

Description

Device for removing hair with controllable laser source The invention comprises a device for removing hair with a laser source, an adjustable laser manipulator for positioning said beam that generates a source during the operation at a certain position on the part of the skin to be treated, and a sensor for image to detect images of at least a part of the skin.

There is a device for removing hair of the type mentioned in the previous paragraph under US Pat. No. 5,653,706, which is designed for use by professional therapists and which can be used not only to remove hair but also for other dermatological treatments such as hair removal. of necrotic tissue, varicose veins, or pigments. The therapist can see the image of the skin detected by the image sensor on a screen. Also, this device comprises a control with which the therapist can operate the laser manipulator with what can guide the beam generated by the source manually on the skin to be treated. When working on the skin, the laser beam has a relatively low energy density, in addition to the therapist can monitor the position of the laser beam on the skin seeing the image on the screen. When the laser beam is in the position desired by the therapist, it can be intensified for a predetermined period of time by the same by means of the control panel of the device. The laser beam has a wavelength that the tissue to be treated can absorb appropriately, so that the tissue that is near the portion to be treated is heated locally to alias temperatures, thereby dying the tissue relevant. For a permanent removal or hair removal present in the skin, the laser beam is aimed at the hair root, so that it and the surrounding tissue die. Since this device comes with an image sensor and an adjustable laser beam manipulator, it is possible to treat the skin locally with a laser beam of a relatively small diameter, so that the source of the laser needs a small amount of energy. Also, the device uses a small and simple LED diode.

A disadvantage of the device is that a relatively long treatment time is needed to remove the hairs present on the skin being treated, that the therapist must manually move the laser beam from one hair to the next. In addition, to determine the desired position of the laser beam on the skin, the user needs to have some experience, so that the device is for the exclusive use of the professionals in the area.

One of the purposes of the invention is to provide a device for removing hair of the type mentioned in the opening paragraph with which the skin can be treated in a relatively short period of time, and which can be used by inexperienced persons, i.e. for the consumer market.

To achieve this objective, the device for removing hair according to the invention is characterized in that the laser source can be controlled with an electric control unit, which determines the position in which it is desired to place the laser beam during the operation to know the position / orientation of the hair that is going to be removed in the skin as determined by the control unit using the image. Said unit activates the laser source at the moment in which the laser manipulator is in the desired position. The determination of the desired position of the laser beam and the activation of the laser source are completely automatic since the control unit determines the position of the laser beam and activates the laser source when the laser manipulator is in the desired position. Likewise, the control unit allows, for example, to adjust the laser manipulator in a predetermined and automatic manner in the desired position on the skin, with which the aforementioned device can be used by inexperienced people in complete safety, so that it is very appropriate for the consumer market. The control unit comprises, for example, an algorithm for the image sensor to detect the desired position using the image of the skin. The algorithm is able to determine the position / orientation of the hair. The automatic determination of the desired position as described above, as well as the automatic adjustment of the laser manipulator and the automatic activation of the laser source take place in a relatively short period of time, so that the treatment time is also reduce using the mentioned device.

A special feature of the device for removing hair mentioned is that the control unit determines the desired position of the laser beam in a periodic sequence of consecutive partial regions of the image. The laser beam manipulator can be adjusted with the control unit in each partial region in a position corresponding to the desired one over the relevant partial region. A special feature of the invention is that the control unit scans the detected skin image periodically in accordance with said sequence of consecutive partial regions, over which the control unit adjusts the laser manipulator in the desired position. An advantage of this special feature is that the laser manipulator does not need to scan the entire skin portion corresponding to the image, but simply adjusts consecutively to the desired position as determined in the consecutive partial regions of the image. While it is true that, at that point the control unit adjusts the laser manipulator in an irregular manner, so that the requirements for time and accuracy of adjustment are greater, the treatment time of the device is greatly reduced .

Another special feature of the device for removing hair according to the invention is that the control unit determines a region on the skin below which the root of a hair can exist with a predetermined degree of probability, using the position and orientation of the hair that is you want to remove, as determined by the image, the control unit determines at least one desired position on the skin in said region. Thanks to this feature, the device can also be used for hair removal: since the laser beam treats the hair root, it dies as well as the dermal tissue present in the immediate vicinity, so that the hair is permanently removed, or at least for an extended period of time. The region of the skin below which the control unit considers that a root exists, calculated with the predetermined degree of probability on the basis of, for example, prior statistical information about the length of the subcutaneous portions of the hairs and the angle of subcutaneous portions of hair with respect to the surface of the skin.

Another main characteristic of the device for removing hair according to the invention is that the control unit can adjust the laser manipulator in a sequence of consecutive positions corresponding to the displacement of the laser beam in a rectilinear path on the skin with a predetermined speed. This rectilinear route is at a practically right angle that almost completely coincides with the perpendicular projection of the hair to be removed from the skin. The control unit activates the laser source at the beginning of the movement. Thus, the skin region mentioned above, below which it is believed that a root with the predetermined degree of probability exists can be treated efficiently in its entirety, in addition to which the required diameter of the laser beam is considerably reduced.

A particular feature of the device for removing hair according to the invention is that the control unit adjusts the laser manipulator in a series of numbers of consecutive fixed positions corresponding to a number of fixed desired positions of the laser beam in a rectilinear path of the laser. skin. This route is in an almost straight line that practically coincides with the perpendicular projection of the hair that is going to be removed from the skin. The control unit activates the laser source of each of the mentioned fixed positions of the laser manipulator for a predetermined period of time. Said region of the skin below which a root with the predetermined degree of probability is believed to exist can be treated efficiently in its entirety, in addition to which the required diameter of the laser beam is considerably reduced.

Another feature of the device for removing hair according to the invention is that the control unit determines the exit position of the hair in the place where it leaves the skin, from the position and orientation thereof in the skin as determined by the image, the Control unit equalizes the desired position of the laser beam with a position of the eye adjacent to said exit position. With this characteristic, the device can be used as a shaver, thanks to the fact that the desired position of the laser beam is located in the vicinity adjacent to the exit position thereof, so that it will be burned by action or the laser beam adjacent to the position of exit, that is, adjacent to the surface of the skin. For example, you can program the control unit so that the desired position is on the same level as the surface of the skin, or even below it, which results in a smooth and flush shave that is maintained for a period of time. relatively long The device could also include a piece to adjust it to the desired position in relation to the surface of the skin so that the user can modify the softness.

Another special feature of the device according to the invention is that it includes independent illumination to illuminate at least the portion of the skin that will detect the image sensor, with which the light of this piece is projected to project said image reflected by the skin, In addition to being able to completely switch off between each exposure of two consecutive desired positions, it is not necessary for the light reflected by the laser beam to reach the image sensor since it detects the image that forms the piece of illumination reflected by the skin. For this purpose, the image sensor can include a filter for the light that reflects the laser beam, so that it is protected against damage that this light could cause at the moment when it is in the desired position and that its energy density is high.

A further feature of the device for removing hair according to the invention is that, thanks to the image, the control unit determines a reflection spectrum of the portion of the skin detected by the image sensor. The unit compares the reflection spectrum with a predetermined reference spectrum of at least one of the skin deviations that occur frequently, while, thanks to said comparison, it determines the positions in which there is said skin deviation, To deactivate the source (laser beam in the positions mentioned above), thanks to this feature, the laser beam can not point to the positions in which the deviation of the skin is found, such as a mole or other type of pigmentation. that such deviations have a relatively high absorption power for the laser that is used in the treatment of hair and roots, which would cause injuries by contact with said beam, which does not happen with this special feature, which provides automatic protection against said wounds Another feature of the device for removing hair according to the invention is that the control unit has means for determining the actual position of the laser beam on the skin, by means of the image detected by the image sensor. Thanks to the determination of the actual position of the laser beam on the skin, the laser beam manipulator can, for example, be corrected or calibrated so that the actual position corresponds precisely to the desired position determined by the control unit. Since the image sensor determines the actual position, it is not necessary to have a separate sensor to determine it, in addition to the fact that the image sensor is used effectively.

A further feature of the device according to the invention is that the control unit adjusts the laser manipulator by means of an output signal thereof according to a predetermined mathematical relationship between said output signal and the desired position. The control unit has an attachment to calibrate the predetermined mathematical relationship based on the measured ratio between the output signal and the actual position of the laser beam on the skin. Since the control unit adjusts the laser manipulator according to said mathematical relationship between the output signal and the desired position, the control unit can determine the output signal needed to reach the predetermined desired position in a relatively short period. Since the mathematical relationship is calibrated based on the measured ratio between the output signal and the actual potion, the laser beam handler can place the precision beam in the desired position with great precision, so that the damage caused by the Laser beam to the skin adjacent to the desired position is reduced as much as possible, plus it always shoots to the desired position.

One particular characteristic of the device for removing hair according to the invention is that the control unit activates the laser source with a relatively low energy density to determine the actual position of the beam on the skin. When the laser source is activated - at low energy density - the beam generates a spot on the skin that is bright enough to be detected by the image sensor, but without damaging or irritating the skin. In this way, the control mechanism of the unit can determine the actual position of the laser beam on the skin in a safe and reliable way, as well as saving a lot of energy.

The invention is explained in greater detail below with reference to a drawing in which: Fig. 1 shows, with the help of a diagram, a device for removing hair according to the invention, Fig. 2. shows, with the help of a diagram, a section of the skin to be treated that is adjacent to the hair to be removed with the device for removing hair of Fig. 1, Fig. 3 shows, with the help of a diagram, an image of the portion of skin that is under treatment and that is detected with the image sensor of the device for removing hair of Fig. 1, Fig. 4 shows, with the help of a diagram, the control unit of the device for removing hair of Fig. 1, Fig. 5a shows, with the help of a diagram , a partial region of the image of Fig. 3, Fig. 5b shows, with the help of a diagram, a partial region of the image of Fig. 3 from a different angle of the device for removing hair according to the invention. Fig. 6 shows, a reflection spectrum determined by the control unit of Fig. 4 of the image of Fig. 3, Fig. 7 shows, with the help of a diagram, the control unit of the device for removing hair from another angle, Fig. 8 shows, with the help of a diagram, a partial region of the skin image that is under treatment generated by the control unit of Fig. 7, and Fig. 9 shows , with the help of a diagram, a partial region of a skin image that is under treatment generated by the device control unit. The device for removing hair 1 according to the invention shown with the help of a diagram of Fig. 1, comprises a laser source 3 and a laser manipulator 5 for positioning the laser beam 7 that generates the laser source 3. during the operation in the desired position 9 on the skin 11 to be treated. The hair removal device 1 is an epilator for removing the hairs 13 from the skin 11 for a relatively long period of time or even permanently. In case a hair 13 is depilated, the desired position 9 of the laser beam 7 must be in a position of the skin 11 approximately below the root 15 of the hair 13, as shown with the help of a diagram of Fig. 2. the laser beam 7 contains monochromatic light with a wavelength that is well absorbed by the hair 13, while the absorption of the skin tissue is bisexual. Thanks to this, the 15th root of hair 13 is practically the only part that is heated at high temperatures, so that it dies. Because its wavelength is between 650 nm and 1200 nm (in the case of white skin with dark hairs), the optical selectivity between the hairs 13 and the skin tissue 11 is excellent. The light of such wavelength is well absorbed by melanin, a pigment that develops in large concentrations both in the outer layer of the skin (epidermis) and in the skin tissue that develops in its inner layers, where they grow the roots 15 of the hairs 13. In addition, it is necessary that the duration of the pulse and the density of the energy of the laser beam are sufficient, since if the duration of the pulse is too short, only the root would be heated and not the tissue next to it, leaving that one intact, resulting in the development of more roots and, hair in that region. On the other hand, if the pulse is too long, the tissue adjacent to the root 15 would be overheated due to thermal conduction, which, in turn, could cause irritation or even damage. To obtain the best results, the pulse duration of the laser beam 7 must be between 1 ms and 10 ms, while the energy density must be between 15 J / cm2 and 50 J / cm2. The laser beam 7 can be precisely positioned in the desired position 9 by means of the laser manipulator 5 in the manner described in greater detail below, while the desired position 9 can be precisely determined with the electric control unit. 17 of the device for removing hair 1, in the manner described in greater detail below. Thanks to this, the laser beam 7 needs only a small diameter to heat the root 15. To obtain the best results, the diameter of the laser beam 7 should be between 0.3 mm and 1.0 mm. This small diameter means that the laser source 3 needs a relatively low output power (of a few) watts so that the energy density and pulse duration of the laser beam are sufficient. The laser source 3 used in the hair removal device 1 also includes a small and simple laser diode which is known as the same name and which does not appear in Fig. 1, or a series of laser diodes coupled with fiber that is they know by the same name and that neither appear in Fig. 1. the laser source 3 also includes a collimator lens system that also does not appear in Fig. 1 and by means of which the laser beam 7 is pointed in almost parallel direction As shown in FIG. 1, the laser manipulator 5 comprises a first adjustable and tiltable mirror 19 and a second mirror 21, also tiltable and adjustable, both being placed at an angle of approximately 45 ° with respect to the contact surface 23 with which the device for removing hair 1 comes into contact with the skin 11 the first mirror 19 can be inclined at limited angles around the first tiltable axis 21 extending in the plane of the first inchnable mirror 19 and parallel to the contact surface 23 by means of an actuator 25 shown in the graph of FIG. second tiltable mirror 21 is inclined at limited angles following the second axis of inclination 31 that rests on the plane of the second inchnable mirror 21 and which crosses the first axis of inclination 27 almost perpendicularly by means of an actuator 9 which is also shown in FIG. the graph of Fig. 1 The laser beam 7 generated by the laser source 3 during the operation is reflected in the first 19 and second 21 inchnable mirrors at approximately 45 ° angles, so that the laser beam 7 touches the skin 11 which is under treatment almost perpendicularly in the desired position 9 through an opening 33 which is in the contact surface 23 the opening 33 can be covered with a plate of transparent material, while the desired position 9 of the laser beam 7 on the skin 11 is displaceable in parallel to an X direction, which rests on the contact surface 23 and which crosses the first inclination axis 27 of perpendicular manner, while the actuator 25 inclines the first inchnable mirror 19 on the first inclination axis 27 the desired position 9 of the laser beam 7 on the skin 11 can be moved in parallel to a Y direction, which also rests on the surface of contact 23 and which is perpendicular to the X direction, while the actuator 29 inclines the second tiltable mirror 21 on the second axis d inclination 31 As shown in Fig. 1, the hair removal device 1 includes a mechanism of illumination 35 by means of which a portion of the skin 11 that is being treated below the aperture 33 is illuminated. The illumination mechanism 35 may be a simple lamp. The lighting mechanism 35 produces a beam of light that generates a ray of light passing through a transparent plate 39, which also transmits the laser beam 7 and is placed on said portion of the skin 11. The transparent plate 39 is placed at an angle about 45 ° with respect to the contact surface 23, in addition to including a reflecting surface 41 on one of the sides which is opposite the opening 33. The reflecting surface 41 reflects a light beam 43 which was already reflected by said portion of the skin 11 through an angle of approximately 90 ° and is concentrated on the CCD image sensor 47 which is known by the same name in the figure shown, by means of a lens unit 45. For this Accordingly, the image sensor 47 can detect an image of said portion of the skin 11 present below the aperture 33. By using a lighting mechanism 35 the image sensor 47 can detect a clear image of said portion of the image. 11 skin thanks to the light of the lighting mechanism which is reflected by the skin 11, so that it is not necessary to have the light reflected from the laser beam 7 to detect said image, which means that the laser source 3 can be completely turned off between the exposures of two consecutive desired positions on the 11. Likewise, the image sensor 47 may include a filter (not shown in Fig. 1), for the light reflecting the falling ray 7, so that the image sensor 47 is protected against damage that could cause the light reflected by the laser beam 7 when it is in the desired position 9 with a high energy density. According to FIG. 1, the image sensor 47 produces an electrical signal that receives the control unit 17 corresponding to the image of the skin potion 11 present below the aperture 33 detected by the image sensor 47. Blister signal JS comprises, for example, a series of 8-bit gray tone values of the pixels of the image sensor. The detected image is shown in the graph of Fig. 3 and is indicated by the reference number 49. As shown in Fig. 4, the control unit 17 comprises a first processor 51 that scans the detected image 49 more or less periodically. Said processor 51 generates a succession of numbers of partial regions 53 of the image 49 as shown in Fig. 3, especially a more or less periodic sequence of the partial regions 53 that descasan approximately in a series of lines which, in turn , they rest approximately on a series of lines that also rest one behind the other as seen in the Y direction, which expand parallel to the X direction. The first processor 51 provides a one usp electrical signal to a second processor 55. of the control unit 17, which corresponds in succession to the partial regions 53 of the image 49 successively generated by the first processor 51. In each of the partial regions, the second processor 55 determines the position and orientation of the skin 11 of the hair or hairs 13 present in the relevant partial region 53 in each partial region and provides an electrical signal apo to a third processor 57 of the control unit 17 corresponding in succession to the positions and orientations of the hairs 13 in the consecutive partial regions 53 of the image 49 as determined by the second processor 55. In each partial region 53, the third processor 57 determines one or more desired positions for the laser beam 7 as a function of said position and orientation of the hair or hairs 13 in the relevant partial region 53 in the manner described in more detail below. The partial regions 53 have dimensions that were determined based on a predetermined average distance between the hairs 13 present on the skin 11 and a also predetermined length of the hairs 13. In the figure, the dimensions of the partial regions 53 allow them to include an average of only one hair 13 per region, which can be achieved in practice if the user cuts the hairs 13 almost flush using a shave before treatment with the device to remove hair 1 so that the length of the hairs 13 is less than the average distance between them. For best results, you can, for example, cut hairs 13 to a length between 1 mm and 2 mm when the average distance between hairs 13 is 3 mm to 3 mm. The first processor 51 generates the consecutive partial regions 53 of the image 49 so that the hair 13 present in the partial region 53 is approximately in the center of the relevant partial region 53. Therefore, the sequence of the consecutive partial regions Obviously it will not have the periodicity shown in Fig. 3, but it will be more or less regular, with the possibility, for example, of having a space between the consecutive 53 partial regions, or that they are not exactly in one line. Since the partial regions 53 contain on average only one hair 13 each, the second 55 and third processor of the control unit 17 can determine the position and orientation of the hair 13 in the partial region 53 and the desired positions of the laser beam 7, respectively, within a short period of time, in addition to greatly reducing the computing capacity required of the second 55 and third 57 processors. Ideally, the vellc removing device 1 includes an adjustment mechanism (not shown in the figures) with which the user can configure the dimensions of the partial regions 53. For this purpose, the adjustment mechanism sends an electrical signal Ua to the first processor 51 corresponding to the dimensions configured by the user, who can adapt them according to the properties of the skin to be treated, especially at the average distance between the hairs of the skin and the average length of the shaved hairs, so each user can optimize the result and time of the treatment. As shown in Fig. 4, the third processor 57 provides an electrical signal utp to a fourth processor 59 of the control unit 17, whose signal corresponds consecutively to the position of the laser beam 7 which detonated the third processor 57 in the regions Consecutive Partials 53. The fourth processor 59 determines a first output signal um1 and a second output signal um2 of the control unit 17, by means of which, the control unit 17 corollates the first 19 and second 21 incunable mirrors of the laser beam manipulator 5, respectively, as a function of the utp signal. The fourth processor 59 determines the output signals um1 and um2 so that the incunable mirrors 19 and 21 are adjusted in the positions corresponding to the desired position of the laser beam 7 in the relevant partial region 53 corresponding to the utp signal each time . The fourth processor 59 also provides a third output signal ul of the control unit 17 by means of which it controls the laser source 3. The fourth processor 59 generates an output signal ul at a predetermined time after producing the signal signals. output um1 and um2. said predetermined moment corresponds to a necessary predetermined adjustment time of the mirrors 19 and 21. The fourth processor 59 provides an output signal ul with the predetermined pulse duration, so that the laser beam 7 is activated in the corresponding desired position with the default pulse duration. The control unit 17 scans the detected image 49 periodically in the manner described above according to said sequence of consecutive partial regions 53. The control unit 17 adjusts the laser manipulator 5 in consecutive positions that only correspond to the desired positions determined in the consecutive partial regions 53., which means that the laser manipulator should only be adjusted to a limited number of consecutive positions, so that the treatment time is particularly short. However, the laser beam manipulator 5 is adjusted relatively randomly during this process, so that the precision adjustment requirements thereof are higher besides that more time is needed to achieve the required adjustment accuracy. Since the control unit 17 activates the desired positions of the laser beam 7 automatically after the laser manipulator 5 is adjusted - also automatically - in the correct and precise position corresponding to the desired position that determined the attached to control 17, the device for removing hair 1 according to the invention is particularly suitable for use by inexperienced persons, which makes the device highly advisable for the consumer market. The time needed to determine the desired positions of the laser beam 7 (which are described in greater detail below), to adjust the laser handler 5 automatically and to activate the laser source 3 - also automatically - it is relatively short, which also reduces the treatment time with device for removing hair 1 according to the invention. The desired positions of the laser beam 7 are determined within a partial region 53 of the detected image 49 by the control unit 17 in the following manner: Fig. 5a shows a graph of the partial region 53 in which there is a hair 13 to be depilated. Thanks to the usp signal, the second processor 55 of the control unit 17 determines the distribution of shades of gray of the relevant partial region 53, from which the position and orientation of the hair 13 on the skin 11 are determined. second process 55 also draws a distinction between the end of the hair 63 and its exit position 65 where the hair 13 connects with the skin 11. This distinction is made by means of characteristics of shades of gray and shape, both predetermined, of ends of cut hairs and their exit positions, which are stored in the memory of the second processor 55. Then, thanks to the position and orientation of the hair 13 and to the exit position 65, the third processor 57 of the control unit 17 determines a region 67 of skin 11 below which is considered to have a root 15 with a predetermined degree of probability. In the figure shown, when determining said region 67 it is assumed that the root 15 is practically at a distance of rectilinear subcutaneous extension 69 of the hair 13, that is, that it leaves the exit position 65 detected, while also being assumes that an angle c shown in Fig. 2 between the hair 13 and the surface of the skin 11 and the length L, (which is also shown in Fig. 2) of the portion of hair 13 that lies below it is located between minimum and maximum values that are previously determined in a statistical way. The region 67 determined in this manner is elongated and expanded along a straight line segment 71 which is located on an imaginary line that almost perfectly matches the perpendicular projection of the hair 13 on the skin 11. Then, the third processor 57 determines a number (eg, 3) of positions 9,9 'and 9"of the laser beam 7 on the segment of the line 57, which overlap each other in a small portion each time The third processor 57 sends a series of signals utp consecutive to the fourth processor 59 corresponding to said positions 9, 9'and 9". Accordingly, the fourth processor 59 of the control unit 17 adjusts the laser manipulator 5 to the number of consecutive fixed positions thereof. Fig. 5b shows a partial region 53 of the detected image 49 with another characteristic of the hair removal device 1 according to the invention. According to the above, the third processor 57 sends an utp signal to the fourth processing 59 which corresponds to the displacement of the laser beam 7 with a speed v on said straight line segment 71, so that the fourth processor 59 adjusts the laser manipulator 5. in a sequence of consecutive positions corresponding to said displacement of the laser beam 7. The fourth processor 59 of the control unit 17 using this alternative activates the laser source 3 at the beginning of said displacement, while the fourth processor 59 turns off the source of laser 3 at the end of the movement. To obtain similar results achieved in the alternative of Fig. 5a, said predetermined velocity v of the laser beam 7 must be approximately equivalent to a quotient of the diameter of the laser beam 7 and to the pulse duration used in Fig. 5a. In the representation of Fig. 4, the control unit 17 also has a fifth processor 73 that determines a reflection spectrum of the portion of the skin 11 that lies below the opening 33 of the image 49 detected by the sensor of images 47, that is, of the signal us, and that compares this reflection spectrum with a predetermined reference spectrum that is stored in the memory of the processor processor 73 and that contain characteristic information of at least one deviation of the skin 11 that It happens frequently. FIG. 6 shows an example of said reflection spectrum, in which the horizontal axis represents a measured gray tone G and a vertical axis represents a series of pixels N of the image sensor. The reflection spectrum shown comprises a relatively large first peak A with shades of gray corresponding to the white skin, a relatively small second peak B with shades of gray corresponding to dark hairs and a third peak C with corresponding shades of gray; said deflection of the skin 11. Thanks to said comparison, the fifth processor 73 determines the positions on the skin 11 where said deviation is located and sends an electrical signal ubp to the sixth processor 75 of the control unit 17 corresponding to the positions on the skin 11 of said deflection thus determined. The sixth processor 75 compares the utp signal, which corresponds to the desired position of the laser beam 7 determined by the third processor 57, with the positions on the skin 11 of said deviation thus determined, and sends a ustop signal to the fourth processor 59 in the exact place in that the desired position of the laser beam 7 coincides with one of the positions of said deflection on the skin 11. When the fourth processor 59 receives the ustop signal, the fourth processor 59 refrains from activating the laser source 3. When using the fifth 73 and sixth 75 processors, the laser beam 7 is prevented from activating in positions of the skin 11 where said deviations are found, such as moles or other pigmentations. The absorption power to the laser beam 7 of these deviations is relatively high, so that if the laser beam 7 comes into contact with said deviations, lesions could appear, so that, when using the fifth 73 and sixth 75 processors, it is obtained automatic protection against such injuries. In the representation of Fig. 4, the fourth processor 59 determines the output signals um1 and um 2 in accordance with a predetermined mathematical relationship between the signals um1, um2 and the desired position 9 of the laser beam 7 as determined by the third processor 57. Said mathematical relationship is, for example, a linear function or a function of a greater degree comprising a series of coefficients. It is possible that, due to temperature fluctuations or other factors, deviations from the desired position 9 caused by a predetermined value of the output signals um1 and um2 may occur. such deviations can lead to a decrease in the efficiency of the device for removing hair 1 and in irritation or damage to the skin. In order to reduce or avoid such deviations and provide jn high precision positioning of the laser beam 7 on the skin 11 using the mirrors 19, 21, the control unit 17 also has a calibration mechanism 81 psra to calibrate said predetermined mathematical relationship based on the measured ratio between the output signals um1, um2 and the actual position of the laser beam 7 on the skin 11. For example, with said calibration those coefficients of the predetermined mathematical relationship are recalculated based on the measured ratio between the output signals um1, um2 and the actual position of the laser beam 7 on the skin 11, a task performed by the control unit 17, for example, each time the hair removal device 1 is turned on or after each interval of predetermined time To perform the calibration, the mirrors 19 and 21 are positioned consecutively in a predetermined number of calibration positions. To this end, the fourth processor 59 sends a series of output signals um1 and um2 having predetermined values. At each calibration position of the mirrors 19 and 21, the actual position of the laser beam 7 on the skin 11 is determined using a seventh processor 83 of the control unit 17, which determines said current position using the image detected by the sensor 47. For this purpose, as shown in Fig. 4, the seventh processor 83 receives the us signal provided by the image sensor 47, and sends an uap signal to the calibration mechanism 81, which corresponds to the actual position of the sensor. laser beam 7 on the skin 11. After determining the actual position of the laser beam 7 in each calibration position of the mirrors 19 and 21, the calibration mechanism 81 sends a ucal signal corresponding to the recalculated coefficients of the predetermined mathematical relationship to the fourth processor 59. During the calibration process, the fourth processor 59 activates the laser source 3 with a relatively low energy density by means of a value appropriate signal ul. This energy density is as low as possible, but it is sufficiently bright to be detected by the image sensor 47. This prevents the skin from becoming irritated or damaged during the calibration process., in addition to saving on the power consumption of the laser source 3. The invention can also determine the actual position of the laser beam 7 on the skin 11 in a similar manner using the image detected by the image sensor 47, but with the difference that the laser manipulator 5 is corrected differently. For example, it is possible that the control unit 17 may also include a feedback control circuit with a comparator which distinguishes between the actual position of the laser beam and the desired position and which marks an error signal. It can also include a PID regulator, which determines the output signals um1 and um2 based on said error signal in such a way that the actual measured position is equal to the desired position. The invention can also determine the actual position of the laser beam in the skin without using the image sensor, using an independent sensor such as, for example, the sensors that directly measure the angular positions of the mirrors 19 and 21. As shown in FIG. 1, the device for removing hair 1 according to the invention also has a handle 81 by means of which the user can place the device 1 on the skin 1 1 to treat it and then move it. As described above, only the portion of skin 11 which is below the opening 33 is treated after said portion of the skin 11 has been treated, the user must move the device to remove hair 1 at the next position. The hair removal device 1 may include, for example, an acoustic source which is activated by the control unit 17 to produce an acoustic signal when the treatment of the skin potion 11 which is below the opening 33 is finished. The hair removal device 1 may also include, for example, an impulse electric medium controlled by the control unit 17 to automatically move it on the skin 11 to be treated, instead of using the acoustic source. Fig. 7 shows a control unit 17 'forming part of a hair removal device 1' according to the invention. Apart from said control unit 17, the hair removal device 1 'has a composition comparable to that of the hair removal device 1 according to the invention of Fig. 1. The components of the hair removal device 1' correspond to those of the device. 1 described above and have the same reference numbers of Fig. 7, in addition to the following description deals exclusively with the differences between the control units 17 and 17 'and the resulting differences in the operation of devices 1 and 1 ' As shown in Fig. 7, the control unit 17 'also has a first 51, a second 55, a third 57, a fourth 59, a fifth 73 and a sixth 75 processor. The control unit 17 'also has a seventh processor 77 which determines the first um1 and second um2 output signals by means of which the control unit 17' controls the first 19 and the second 21 incunable mirrors of the laser manipulator 5 , respectively. Also, the control unit 17 'includes a calibration mechanism 81 and an eighth processor 83 corresponding to the calibration mechanism 81 and the seventh processor 83 of the control unit 17 and working together with the image sensor 47 and with the seventh processor 77 in a similar manner in which the calibration mechanism 81 and the seventh processor 83 of the control unit 17 correspond to the image sensor 47 and the fourth processor 59. The seventh processor 77 determines the output signals um1 and um2 in such a way that the mirrors 19 and 21 are adjustable to a sequence of consecutive positions corresponding to a regular sequence of virtual positions of the laser beam 7 on the skin portion 11 that is below the opening 33, especially with a displacement of the virtual position of the laser beam 7 with a speed v 'according to a series of lines that extend parallel to the X direction and follow one another as seen in the Y direction. As shown in Fig. 7, the seventh processor 77 commands an electrical signal uip to the first processor 51 corresponding to the virtual instantaneous position IP of the laser beam 7. The first processor 51 generates a partial region 53 'of the image 49 which is shown in the graph of Fig. 8 whose dimensions are determined by a predetermined average distance between the hairs 13 which are on the skin 11 and a determined length of the hairs 13. The user can configure the dimensions of the partial region 53 'by means of an adjustment mechanism (not shown in FIG. figure) and which sends an electrical signal uA to the first processor 51 corresponding to the dimensions of the partial region 53 'according to the configuration of the user. The first processor 51 generates the partial region 53 'such that the reference position R of the partial region 53' shown in FIG. 8, in particular a central position of the partial region 53 'corresponds in a continuous manner to the instantaneous virtual position IP of the laser beam 7. In this way, the partial region follows the rectilinear displacement of the instantaneous virtual position IP of the laser beam 7 on the image 49. FIG. 8 also shows a series of lines 79 throughout from which the instantaneous virtual position IP of the laser beam 7 moves on the image 49. The first processor 51 sends an electrical signal usp to the second processor 55 corresponding to the partial region 53 'and the second processor 55 determines thanks to the signal usp corresponding to the partial region 53 'of the hair 13 which is in the partial region 53. The second processor 55 sends a upo signal corresponding to the position and orientation of the hair 1 3 in the partial region 53 'as determined by the second processor 55, while, thanks to the upo signal, the third processor 57 determines the desired positions 9, 9', and 9", of the laser beam 7 and activates the source of laser 3 by means of the output signal ul with the pulse duration previously determined at the moment in which the instantaneous virtual position IP of the laser beam 7 corresponds to one of the desired positions 9, 9'and 9"thereof in the region partial 53 '. The fifth 73 and sixth 75 processors of the control unit 17 'have functions comparable to those of the fifth 73 and sixth 75 processors of the control unit 17. An advantage of the device for removing hair 1' with the control unit 17 'adjusts the laser beam manipulator in a continuous and periodic way, so that it is not necessary much precision in the adjustment or a lot of time. The portion of the skin 11 that! > e located below the aperture 33 is scanned by the laser manipulator 5 periodically, and the partial region 53 'of the image 49 generated by the control unit 17' follows the virtual IP position of the laser beam source 7. of said portion of the skin 11, the desired positions 9, 9 'and 9"of the laser beam 7 continuously changing with respect to the reference point R of the partial region 53', to obtain good results with this embodiment of the device for removing hair 1 'when there is a spacing between the consecutive lines 79 in image 49 which is equivalent or, preferably, smaller than the diameter of the laser beam 7. However, scanning by the laser manipulator 5 of the lines 79 found in the image 49 takes longer than the direct movement of the laser manipulator 5 to the consecutive desired positions in the image 49 according to the device for removing hair 1, so that, in most cases, the treatment time of the device 1 'will be longer than that of the device 1. The devices for removing hair 1 and 1 'described above are depilatory apparatuses which remove hairs 13 from skin 11 for a relatively long period or even permanently. A device 1"according to the invention functions as a shaver; its construction is quite similar to that of the device 1 shown in Fig. 1. The device 1"differs from the 1 in that it determines the desired position 9 of the laser beam 7 on the skin 11 in a different manner. shows a partial region 53"of the image 49 of the skin 111 under treatment which is detected by means of the image sensor 47 of the device 1. The third processor 57 of the control unit 17 of the device 1"determines the position 9 of the laser beam 7 in such a way that the position desired 9 is on the hair 13 to be removed and which is adjacent to the exit position 65 of the hair 13 determined by the second processor 55. The laser beam also burned the hair 13 adjacent to the exit position 65. The The control unit 17 of the device 1"can be programmed so that the desired position 7 is placed on the surface of the skin 1 1 or even below it, so that the device 1" offers a smooth and flush shaving, which it is maintained for a relatively short time. The hair removal device 1"can also include an adjustment mechanism by means of which the user can adjust the location of the desired position 9 relative to the surface of the skin 1 1, thus adjusting the desired smoothness. Laser 7 can burn the hairs 13 using a density energy relatively lower than the density needed to depilate the hairs 13 described above.The device for hair removal 1"can thus include a relatively smaller and cheaper laser diode with a power of, for example, between 100 mW and 500 mW.

The invention also covers a device for removing hair in which the shaving and shaving functions described above are combined, in which case, the user can select the desired mode of operation, for example, using an adjustment mechanism. Preferably, the energy density of the laser source can also be controlled with the control unit of said device, so that the energy density of the laser source can be adapted to the mode of operation thereof. In case the device has the function of hair removal or that the user has configured it as such, it can also include, for example, an automatic shaving function. In case the device for removing hair has only the function of hair removal - in which case only the roots 15 of the hairs 13 are destroyed, they would not disappear from the skin 11 until after some time, so that no results are achieved. immediate. In case the hair removal function is combined with the shaving function automatically, not only will the roots 15 of the hairs 13 be destroyed, but these also burn through the surface adjacent to the skin 11, so that the hairs 13 are immediately removed from it and the desired result is achieved instantaneously. Also, the device for removing hair according to the invention can include a different type of laser manipulator instead of the laser manipulator 5 having two incunable mirrors 19 and 21 as described above. Thus, for example, said mirrors can be replaced by a single one that can be tilted on two incunable axes that are perpendicular to each other. Instead of the laser manipulator with one or more incunabula mirrors, for example, another laser manipulator can be used that comes with a slide that can be moved in two directions perpendicular to each other, in which case, the source of The laser and the image sensor would be attached to the slide in fixed positions. Also, the invention also covers a mode in which the device uses a type of image sensor to the CCD image sensor 47 described above. An example of said image sensor is the CMOS which can include RAM memory, so that it can be integrated to part of the control unit or even all of it. The construction and production of the hair removal device are considerably simplified in the following manner. In this embodiment, the device, according to the invention described above, the control unit determines the desired position of the laser beam each time in a partial region of the skin image detected by the image sensor. The invention also comprises embodiments in which the control unit determines the positions of the laser beam once and for all in the whole of the skin image detected by the image sensor. Nevertheless, said modalities require a control unit with a relatively large calculation and memory capacity. Finally, the invention also comprises embodiments in which the position of the hairs on the skin to be treated are not detected by means of the light reflected by the lighting mechanism, such as the one described above, but in which the position of the hairs are detected by means of the light that reflects the laser beam. The skin to be treated is scanned by means of the laser beam in said modalities, in which the

Claims (14)

Laser beams have a relatively low energy density, but that is increased in the desired position. The light that reflects the laser beam can be detected in said modalities, for example, by means of a simple photo detector that detects only the intensity of the light reflected by the laser beam. Therefore, the expression "sensor" of images to detect an image of at least a portion of the skin "in the preceding paragraphs also includes said photo detector.This detection method can be used in a simple manner with the device 1 'described with reference to Fig. 7, but can also be used, for example, with a device that comes with a laser manipulator with movable slides as described above.

1. The invention comprises a device for removing hair with a laser source, an adjustable laser manipulator for positioning said beam that generates a source during the operation at a certain position on the part of the skin to be treated, and a sensor for image to detect images of at least a part of the skin that is characterized in that the laser source can be controlled by means of a control unit, which determines the desired position of the laser beam as a function of a hair position / orientation to be removed as determined by the control unit using the image, and which activates the laser source at the time when the laser manipulator is in the position corresponding to the desired one.

2. A device for removing hair according to item 1, characterized in that the control unit determines the desired position of the laser beam in a partial region of the image that has dimensions determined by a previously determined average distance between the hairs that are in the skin and a previously determined length of the hairs.

3. A device for removing hair according to point 2, characterized in that the dimensions of the partial region of the image can be adjusted.

4. A device for removing hair according to item 2, characterized in that the laser manipulator can be adjusted by means of the control unit in a sequence of consecutive positions corresponding to a regular sequence of virtual positions of the laser beam on said portion of the skin. The reference position of the partial region of the image corresponds to the instantaneous virtual position of the laser beam, while the control unit activates the laser source when the reference position corresponds to the desired position.

5. A device for removing hair according to item 2, characterized in that the control unit determines the desired position of the laser beam in a periodic sequence of consecutive partial regions of the image. The laser beam manipulator can be adjusted using the control unit in each mentioned partial region in a position corresponding to the desired one within the relevant partial region.

6. A device for removing hair according to item 1 characterized in that the control unit determines a region of the skin beneath the skin below which a root is believed to exist, using the position and orientation of the hair to be removed on the skin, as determined by the image with a predetermined degree of probability. The control unit determines at least one desired position in said region.

7. A device for removing hair according to points 5 and 6, which is characterized because the laser manipulator can be adjusted by means of the control unit to obtain a sequence of consecutive positions corresponding to a displacement of the laser beam on a route rectilinear on the skin with a predetermined speed. This route rests on a virtual straight line that coincides almost perfectly with a perpendicular projection of the hair that is going to be removed. The control unit activates the laser source at the beginning of said displacement.

8. A device acing to points 5 and 6, characterized in that the laser beam manipulator can be adjusted by means of the control unit to obtain a series of consecutive fixed positions esponding to a series of fixed positions desired of the laser beam on a rectilinear route on the skin. The route rests on a virtual straight line that coincides almost perfectly with a perpendicular projection of the hair that is going to be removed. The control unit activates the laser source in each of the mentioned fixed positions of the laser manipulator for a predetermined time.

9. A device for removing hair acing to point 1, which is characterized in that the control unit determines a hair exit position where it connects with the skin, thanks to the position and orientation of the hair that is to be removed. the skin, as determined by the image. The control unit equalizes the desired position of the laser beam with a hair position adjacent to said exit position.

10. A device for removing hair acing to item 1, characterized in that the device for removing hair comprises an independent lighting mechanism to illuminate at least the portion of skin that will be detected by the image sensor.

11. A device for removing hair acing to point 1, characterized in that the control unit determines a reflection spectrum of the portion of skin detected by the image sensor, thanks to the image. The control unit compares the reflection spectrum with a predetermined reference spectrum of at least one skin deviation that occurs frequently, while the control unit, using said comparison positions on the skin, determines where said deviation lies. and refrains from activating the laser source in said positions.

12. A device for removing hair acing to item 1, characterized in that the control unit comprises means for determining a real position of the laser beam acing to the image detected by the image sensor.

13. A device for removing hair acing to item 12, characterized in that the laser manipulator can be adjusted with the control unit by means of an output signal thereof, acing to a predetermined mathematical relationship between said output signal and the desired position. The control unit comprises a calibration mechanism for calibrating said predetermined mathematical relationship based on a measured ratio between said output signal and the actual position of the laser beam.

14. A device for removing hair acing to item 122, characterized in that the control unit activates the laser source at a low energy density to determine the actual position of the laser beam on the skin.