WO2009075410A1

WO2009075410A1 - Device and method for stimulating hair using fractional optical pulse

Info

Publication number: WO2009075410A1
Application number: PCT/KR2008/001239
Authority: WO
Inventors: Hae Lyung Hwang; Sung Huan Gong; Won Serk Kim
Original assignee: Lutronic Corporation
Priority date: 2007-12-10
Filing date: 2008-03-05
Publication date: 2009-06-18
Also published as: KR100839023B1

Abstract

A device and method for stimulating hair growth using a fractional optical pulse is provided, which can achieve stimulation of hair growth by irradiating a fractional optical pulse onto scalp to be operated. The device for stimulating hair growth using a fractional optical pulse includes an optical pulse generation unit for generating and outputting an optical pulse; an optical pulse transfer unit, coupled to the optical pulse generation unit, for guiding the optical pulse outputted from the optical pulse generation unit; a handpiece, coupled to the optical pulse transfer unit, for irradiating laser beams onto scalp to be operated; and a divided beam irradiation unit, provided in the handpiece, for dividing the optical pulse transferred from the optical pulse transfer unit into a plurality of fractional beams and simultaneously irradiating the divided fractional beams onto the scalp to be operated.

Description

[DESCRIPTION] [Invention Title]

DEVICE AND METHOD FOR STIMULATING HAIR USING FRACTIONAL OPTICAL PULSE [Technical Field]

The present invention relates to a device and method for stimulating hair using a fractional optical pulse. More particularly, the present invention relates to a device and method for stimulating hair growth using a fractional optical pulse, which can achieve stimulation of hair growth by generating heat on scalp tissue through discrete irradiation of an optical pulse or laser beam pulse onto scalp with a specified depth, and transforming hair follicles from telogen to anagen through the stimulation of stem cells neighboring the hair follicles with the generated heat. [Background Art]

Hair grows and falls out through a three-stage hair cycle including anagen, catagen, and telogen. In case of an adult, daily loss may range about 100 hairs, and if hair loss exceeds the range, it may be alopecia. That is, alopecia is the loss of hair on the body, and is classified according to various causes and symptoms. For example, alopecia may be classified into androgenetic alopecia, alopecia areata, telogen effluvium, and so forth.

The androgenetic alopecia, which is the most representative one among them, is mainly caused by hereditary factors, and may be divided into male- pattern baldness and female-pattern baldness. In the case of male-pattern baldness, male sex hormone is converted into dihydrotestosterone by a catalytic action of 5-alpha reductase, and then is combined with androgen receptor, so that the function of hair papilla and hair follicles deteriorates, and blood vessels are damaged to cause the hair loss. According to the male-pattern baldness, a normal hair cycle cannot be maintained and the period of anagen is shortened. The male-pattern baldness is caused by the change from terminal hair to vellus hair, and has the characteristics that follicles are not lost but just become small, and no change of inflammation occurs in the skin tissue neighboring the follicles. In the male-pattern baldness, hair is lost in a well-defined pattern, beginning above both temples, and hair also thins at the crown of the head. By contrast, in the female-pattern baldness, the boundary lines among the face, scalp, and hair are relatively well preserved, but the hair loss concentratedIy occurs at the crown of the head. The female-pattern baldness is caused by miniaturization of hair follicles rather than destroy of the hair follicles, and the hair follicles in the region where the hair loss has occurred have a decreased duration of due to the increase of the ratio of telogen hair.

The alopecia areata is a form of hair loss from areas of the body, usually from the scalp, and may cause bald spots on the head. The condition of the alopecia areata can spread to the entire scalp (alopecia totalis) or to the entire epidermis (alopecia universalis). In the alopecia areata, although the scalp is seen normal, the anagen is early terminated and the telogen proceeds to cause an abrupt hair loss. According to a tissue examination, the permeation of mononuclear cells such as inflammatory cells, T cell, macrophage cells, and so forth, is shown in peribulbar blood vessels and outer root sheath. Although not yet clearly known, the condition is thought to be an autoimmune disorder in which the body attacks its own hair follicles and suppresses or stops hair growth.

On the other hand, the telogen effluvium is diffuse hair loss caused by any condition or situation that shifts the normal distribution of follicles in anagen to a telogen-predominant distribution to increase the ratio of the telogen hair. It is caused by stress, endocrine disorders, nutrition, medicines, and so forth, and if the stimulation cause is removed, the telogen hair is recovered to normal hair over a several-month period to reduce the hair loss. However, in many patients, the causes of telogen effluvium may not be known, and in this case, the hair loss and the decrease of the hair density may chronically continue.

Although diverse treatments for curing the alopecia have been developed, most hair removers or hair tonics on the market are quasi drugs such as cosmetics for the purpose of a quick circulation of the blood of the skin or a nutrition supply to the hair root, and thus their efficacy has not yet been proved. Also, medical treatments acknowledged by US Food and Drug Administration (FDA) as pharmaceuticals are only minoxidil and propecia, and thus treatment methods satisfactory to alopecia patients have not yet been provided.

Methods for stimulating hair growth using a low-power laser, which are known as methods having improved effects of blood circulation for the alopecia treatment, have been proposed (See Korean Patent Unexamined Publication Nos. 2005-18411, 2005-110573, and 2006-34490). However, these methods have only the effects on the blood circulation of the skin and the damaged tissue, but scientific evidences supporting the actions of the methods on the 5-alpha reductase are insufficient. In addition, a treatise [Avram M. R. et al. "The current role of laser/light sources in the treatment of male and female pattern hair loss", J Cos/net Laser Ther. 2007; 9(1): 27-8] discloses that the treatment using a low-power laser or light has an effect on the male/female pattern hair loss. According to this treatment, however, its scientific support is insufficient, and no research has been made for comparison groups designed for the efficacy. Also, estimation of a patient's hair loss state, patient's body state, and cause of hair loss is insufficient .

Korean Patent Unexamined Publication No. 2003-92331 discloses a hair brush for prevention of hair loss and hair growth stimulation using anions and negative electric potential, and Korean Utility Model Publication No. 388549 discloses a comb for hair growth stimulation using a laser. These hair brush and comb use a low-power laser to directly apply laser beams onto the scalp. However, the low-power laser has limitations in directly activating the hair follicle cells.

On the other hand, a treatise [Bernstein E. F., "Hair growth induced by diode laser treatment", Dermatol Surg. 2005; 31(5): 584-6] proposes a hair growth effect using a high-power laser. However, this is merely an accidental discovery of thick hair growth while hair removal is performed using 810nm diode laser, and researches for stimulation of hair growth have been made incompletely. This is because if the high-power laser is directly applied to the scalp, a large amount of laser is supplied to a specified region of the scalp, and thus the hair and the scalp cells may be damaged. Also, in the case of irradiating the laser beams onto the hair, the laser beams may be reflected to damage a laser fluoroscope.

[Disclosure]

[Technical Problem]

Therefore, the present invention has been made in view of the above- mentioned problems, and it is an object of the present invention to provide a device and method for stimulating hair growth using a fractional optical pulse, which can achieve stimulation of hair growth by transferring heat into a specified depth of a skin layer through discrete separation and irradiation of a condensed optical pulse or laser beam pulse onto scalp with a specified beam density, and by transforming hair follicles from telogen to anagen through the stimulation of stem cells neighboring the hair follicles with the generated heat .

[Technical Solution]

In order to achieve the above objects, in one aspect of the present invention, there is provided a device for stimulating hair growth using a fractional optical pulse, according to the present invention, which includes an optical pulse generation unit for generating and outputting an optical pulse; an optical pulse transfer unit, coupled to the optical pulse generation unit, for guiding the optical pulse outputted from the optical pulse generation unit; a handpiece, coupled to the optical pulse transfer unit, for irradiating laser beams onto scalp to be operated; and a divided beam irradiation unit, provided in the handpiece, for dividing the optical pulse transferred from the optical pulse transfer unit into a plurality of fractional beams and simultaneously irradiating the divided fractional beams onto the scalp to be operated.

The optical pulse may be a laser beam pulse.

The diameter of the fractional beam may be in the unit of micrometers (jαn).

The divided beam irradiation unit may be a micro-lens array having a plurality of micro-lenses for making the laser beams focused within the scalp.

The diameter of the fractional beam may be in the range of 50 to 500 μm.

In another aspect of the present invention, there is provided a device for stimulating hair growth using a fractional optical pulse, which includes an optical pulse generation unit for generating and outputting an optical pulse; an optical pulse transfer unit, coupled to the optical pulse generation unit, for guiding the optical pulse outputted from the optical pulse generation unit; a handpiece, coupled to the optical pulse transfer unit, for irradiating laser beams onto scalp to be operated; a scanner, provided in the handpiece, for making and irradiating fractional beams by successively irradiating the optical pulse transferred from the optical pulse transfer unit in different directions! and a condensing lens for condensing the fractional beams irradiated from the scanner so that the fractional beams are focused within the scalp.

The optical pulse may be a laser beam pulse.

The size of the fractional beam outputted from the condensing lens may be in the unit of micrometers (μm) ■

The scanner may irradiate the fractional beams in random directions in the range of an area of a handpiece tip that is a front end of the handpiece.

The diameter of the fractional beam irradiated onto the scalp may be in the range of 50 to 500/ΛΠ.

A light source of the optical pulse generation unit may be at least one selected from a group composed of a diode laser, a diode pump type solid- state laser, an Er (Erbium) ^"•YAG (Yttrium Aluminum Garnet) laser, a Nd (Neodymium) :YAG laser, an Er÷glass laser, an argon ion laser, a helium-neon laser, a CO2 gas laser, an excimer laser, a fiber laser, a ruby laser, and a frequency multiplied laser.

In still another aspect of the present invention, there is provided a method for stimulating hair growth using a fractional optical pulse, which includes performing a fractional process of an optical pulse and irradiating the fractionally processed optical pulse to scalp to be operated.

The optical pulse may be a laser beam pulse.

The laser beam pulse may be divided into a plurality of fractional laser beams and the divided fractional laser beams may be simultaneously irradiated onto the scalp so that the fractional laser beams are focused within the scalp.

The diameter of the fractional laser beam may be in the unit of micrometers (μm).

The diameter of the fractional laser beam may be in the range of 50 to 500μm.

The fractional laser beams may be generated through successive irradiation of the laser beam pulse in different directions, and then be condensed and irradiated onto the scalp to be operated so that the generated fractional laser beams are focused within the scalp.

The diameter of the condensed laser beam may be in the unit of micrometers (μm).

The diameter of the condensed laser beam may be in the range of 50 to 500μm.

The fractional laser beam may have a wavelength of 400 to 12,000nm,

2 energy per area of 0.001 to 100,000 J/cm , energy per wave of 5OmJ and less, and pulse duration of 100ms and less.

The density of the fractional laser beam may be in the range of 100 to

2 3,000 pieces/cm .

The fractional laser beam may stimulate an area of the scalp that has a depth of 10 to 4,000μm and the diameter of 10 to 1,000/Zm.

[Advantageous Effects]

According to the device and method for stimulating hair growth using a fractional optical pulse as constructed above according to the present invention, stem cells neighboring hair follicles are stimulated through transfer of heat into a specified depth of a skin layer, and thus the hair follicles are transformed from telogen to anagen to achieve the stimulation of hair growth. [Description of Drawings]

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a view schematically illustrating a device for stimulating hair growth using a fractional hair growth according to an embodiment of the present invention;

FIG. 2 is a view schematically illustrating a device for stimulating hair growth using a fractional hair growth according to another embodiment of the present invention;

FIGS. 3 and 4 are views showing results of RT-PCR for observing whether hair follicle cells of scalp are activated after irradiation of high- power fractional laser beams according to the present invention;

FIGS. 5 and 6 are views showing results of western blotting for observing whether hair follicle cells of scalp are activated after irradiation of high-power fractional laser beams according to the present invent ion!

FIGS. 7 to 11 are pictures showing growth of mouse hair after the lapse of seven days and after the lapse of 14 days with irradiation of high- power fractional laser beams according to the present invention;

FIGS. 12 and 13 are pictures showing the degree of hair growth according to the laser energy and the density of fractional laser beams; and

FIGS. 14 to 16 are pictures showing the state of hair growth of alopecia patients before and after the irradiation of high-power fractional laser beams. [Best Mode]

Hereinafter, a device and method for stimulating hair growth using a fractional optical pulse according to preferred embodiments of the present invention will be described with reference to the accompanying drawings. The matters defined in the description, such as the detailed construction and elements, are nothing but specific details provided to assist those of ordinary skill in the art in a comprehensive understanding of the invention, and thus the present invention is not limited thereto.

According to the present invention, in order to discretely separate (i.e., fract ionize) and irradiate an optical pulse or laser beam pulse onto scalp, a device for stimulating hair growth using a fractional optical pulse as illustrated in FIG. 1 or 2 is used.

The device for stimulating hair growth according to an embodiment of the present invention, as illustrated in FIG. 1, includes an optical pulse generation unit 10 for generating and outputting an optical pulse; an optical pulse transfer unit 20, coupled to the optical pulse generation unit 10, for guiding the optical pulse outputted from the optical pulse generation unit 10; and a handpiece 30, coupled to the optical pulse transfer unit 20, for irradiating laser beams onto scalp to be operated. The device for stimulating hair growth according to an embodiment of the present invention also includes a micro-lens array 40, provided in the handpiece 30, for dividing the optical pulse transferred from the optical pulse transfer unit 20 into a plurality of fractional beams and simultaneously irradiating the divided fractional beams onto the scalp to be operated. The micro-lens array 40 is provided with a plurality of micro-lenses for making the laser beams focused within the scalp.

The device for stimulating hair growth according to another embodiment of the present invention, as illustrated in FIG. 2, is provided with a scanner 51 and a condensing lens 52, which are for irradiating the fractional beams condensed by the device as illustrated in FIG. 1, instead of the micro- lens array.

The scanner 51 is provided in the handpiece 30, and makes and irradiates fractional beams by successively irradiating the optical pulse transferred from the optical pulse transfer unit 20 in different directions. The condensing lens 52 condenses the fractional beams irradiated from the scanner 51 so that the fractional beams are focused within the scalp.

In order to receive the optical pulse or laser beam pulse from the optical pulse transfer unit 20, an optical pulse receiving unit (not illustrated) is provided inside the handpiece 30.

In the device as illustrated in FIGS. 1 and 2, it is preferable that the optical pulse is a laser beam pulse, and the diameter of the fractional beam is in the unit of micrometers (μm) , e.g., in the range of 50 to 500//m. It is also preferable that the scanner irradiates the fractional beams in random directions in the range of an area of a handpiece tip that is a front end of the handpiece 30.

The optical pulse transfer unit 20 may be provided with an optical fiber or articulated arm.

According to a process of irradiating the fractional laser beams onto the scalp that is performed by the device for stimulating hair growth as illustrated in FIG. 1, the laser beam pulse from the optical pulse generation unit 10 is incident to the handpiece 30 through the optical pulse transfer unit 20, and then is divided into a plurality of fractional laser beams in the unit of micrometers through the micro-lens array 40 provided in the handpiece 30. The divided fractional laser beams are simultaneously irradiated onto the scalp.

Also, according to a process of irradiating the fractional laser beams onto the scalp that is performed by the device for stimulating hair growth as illustrated in FIG. 2, the laser beam pulse incident from the optical pulse generation unit 10 to the scanner 51 through the optical pulse transfer unit 20 is refracted in predetermined directions or in random directions through the scanner 51, and then is condensed into minute micro-beams through the condensing lens 52. Then, the condensed micro-beams reach the scalp.

A high-power laser that can be used in the present invention may be one of a diode laser, a diode pump type solid-state laser, an Er (Erbium) "•YAG (Yttrium Aluminum Garnet) laser, a Nd (Neodymium):YAG laser, an Er:glass laser, an argon ion laser, a helium-neon laser, a CO2 gas laser, an excimer laser, a fiber laser, a ruby laser, and a frequency multiplied laser, but is not limited thereto. Among the above-described lasers, the Er÷glass laser having a wavelength of 1540 to 1550nm is most preferable.

The scalp stimulated by the laser may include region A having temperatures above 75°C , region B having temperatures of 62 to 75°C , region C having temperatures of 42 to 62°C, and region D having temperatures of 45°C . As the laser beams permeate into the scalp tissue more greatly, the temperature of the scalp is increased, and thus the tissue reaction becomes more active.

In the region C or D having somewhat low temperature, the tissue reaction may not occur. In other words, in order to arouse the reaction in the scalp tissue, the temperature of the scalp should be heightened over a proper temperature, and for this, irradiation of high-power laser beams is required.

The wavelength of the high-power laser beams that can arouse a sufficient stimulation for the scalp is in the range of 400 to 12,000nm, preferably in the range of 500 to 3,000nm, more preferably in the range of 1,000 to 2,000nm, and much more preferably in the range of 1,400 to l,600nm.

The energy per area of the high-power laser beams is in the range of 0.001 to

2 2

10,000 J/cm , and preferably in the range of 1 to 7,700 J/cm . Also, the energy per wave of the high-power laser beams is 15OmJ and less, and preferably 5OmJ and less. Also, the pulse duration of the high-power laser beams is 100ms and less, preferably 50ms and less, and more preferably in the range of 0.01 to 10ms. When the scalp is stimulated by the high-power laser, the stimulation reaches epidermis and dermis of the scalp. The depth of the stimulated scalp region is in the range of 10 to 4,000μm, and the diameter thereof is in the range of 10 to 1,000/zm, preferably in the range of 25 to 750μm, and more preferably in the range of 50 to 500μm. The stimulated scalp region may be in diverse shapes including a circular column.

In the fractional laser process according to the present invention, a dot pitch that corresponds to an irradiation region of the fractional laser beams is important. By the dot pitch, the density of the fractional laser

2 beams for a specified area, for example, for lcm , is determined. That is, under the assumption that the moving distance of a galvanometer is lcm in length and breadth and the dot pitch corresponding to the irradiation region of the fractional laser beams is lmm which is the maximum value, the density

2 of the fractional laser beams becomes 100 pieces/cm , which is the minimum

2 value. If the dot pitch is 312/an, the density becomes about 1024 pieces/ cm , and if the dot pitch is 182μm, the density becomes 3000 pieces/cm at maximum.

Accordingly, the density of the high-power fractional laser beams suitable to the present invention can be set to be in the range of 100 to 300

2 pieces/cm . If the density of the fractional laser beams is heightened through a repeated irradiation, the biological tissue reaction is also heightened.

Hereinafter, embodiments of the present invention will be described in more detail. The embodiments of the present invention below are merely exemplary, but the present invention is not limited thereto.

[Example 1]

-Experiment on activation of hair follicle cells according to the scalp process using fractional laser beams-

In order to confirm whether the hair follicle cells are activated according to the scalp process using the fractional laser beams according to the present invention, the laser irradiation onto the scalp of an alopecia patient was performed using the device for stimulating hair growth as illustrated in FIG. 1 or 2.

In this case, an Er÷glass laser having a wavelength of 1540 to 1550nm was used as the laser light source.

After the laser process, DPC (Dermal Papilla Cells) are separated from the patient participated in the experiment, and the RNA level of a gene involved in the hair cycle was estimated through RT-PCR (Real Time Polymerase Chain Reaction) after 6 hours, 12 hours, and 24 hours, respectively, and the results of estimation were shown as illustrated in FIGS. 3 and 4.

As illustrated in FIGS. 3 and 4, it can be confirmed that the expression of Wntδa and beta-catenin, which are factors in Wnt signaling pathways involved in the phase transition from telogen to anagen, was increased three times, and the expression of PDFG-A and KGF was increased. This means that the scalp stimulation using the fractional laser beams according to the present invention can act upon the hair regrowth through the phase transition in a tissue restoration process of hair papilla cells.

Also, in order to confirm the phenomenon to derive the proliferation of the separated hair papilla cells, the expression of protein Akt and p-Akt that is an activated form of the protein Akt (i.e., phosphate form) was estimated through western blot. The results of estimation were shown in FIGS. 5 and 6.

As illustrated in FIGS. 5 and 6, it can be confirmed that p-Akt was increased about two times in the hair papilla cells with the lapse of time, and this means that the fractional laser beam process derives the proliferation of the cells through the Akt pathway.

[Example 2]

-Experiment on the effect of hair growth of a mouse according to the fractional laser beam process- In order to measure the effect of hair growth according to the hair growth effect according to the process of fractional laser beam, a two-stage experiment as follows was performed.

As the first experiment, hair of back regions of 10 six-week-old S/D (Spraue-Dawely) white mice was removed, five of the mice having clean back skin were selected, and laser beams were irradiated onto their back regions in the same method as that according to example 1. After the lapse of seven days and after the lapse of 14 days with irradiation of the laser beams, respectively, pictures were taken to evaluate the length of hair and the level of hair growth of the respective back region, and the results of experiment for the respective mice were shown as in FIGS. 7 to 11.

Referring to FIGS. 7 to 11, it can be confirmed that after the lapse of 7 days, the growth of hair on the region, onto which the laser beams had been irradiated, became greater and faster in comparison to that on the region onto which no laser beam had been irradiated (i.e., comparison group), and after the lapse of 14 days, the hair growth was extended to the neighborhood of the laser-irradiated regions in a process of treating wound injured due to the laser stimulation.

Also, after the lapse of 14 days, 10 hairs on the laser-irradiated region were selected as an experimental group, and 10 hairs on the region onto which the laser beams had not been irradiated were selected as a comparison group. The results of measuring the hair lengths of the experimental group and the comparison group were shown in Table 1. [Table 1]

From Table 1, it can be confirmed that the hair growth speed of the experimental group became more than twice the hair growth speed of the comparison group.

On the other hand, as the second experiment, other 10 white mice were selected, and the fractional laser beams having different energy [mJ] and 2 density [pieces/cm ] were irradiated onto the back regions of the mice.

FIG. 12 is a picture showing the result of mouse hair growth through irradiation of laser beams having a high energy of 14mJ and a low density of

2

400 pieces/cm onto two regions of the mouse. It can be confirmed that a portion between the two laser-irradiated regions is thickly haired.

FIG. 13 is a picture showing the result of mouse hair growth through irradiation of laser beams having a low energy of 7mJ and a high density of

2

800 pieces/cm onto two regions of the mouse. It can be confirmed that the hair growth is more superior than that as illustrated in FIG. 12.

The results as shown in FIGS. 12 and 13 indicate that the hair growth may differ depending upon the laser energy and the density of the fractional laser beams.

[Example 3]

-Experiment on the effect of hair growth of alopecia patients-

In order to confirm the effect of hair growth and the effect of hair loss prevention, the following experiment was performed.

First, 20 androgenetic alopecia patients (over type II according to Hamilton-Norwood classification method) and 20 alopecia areata patients (who showed no reaction on the existing treatments, e.g., local injection therapy or Immunotherapy, for three months or more) were grouped into experimental groups and comparison groups, each of which is composed of 10 patients. The experimental groups were treated through irradiation of fractional laser beams in the same manner as example 1, at intervals of two weeks, and six times at minimum, whereas the comparison groups were treated through irradiation of low-power laser beams and minoxidil medication.

The results of phototrichogram analysis were shown in Table 2. [Table 2]

In table 1, it can be confirmed that the experimental groups showed a remarkably favorable turn in comparison to the comparison groups.

Also, upper parts of heads of experimental groups before and after the high-power fractional laser process were photographed, and FIGS. 14, 15, and 16 show the upper parts of the heads of male-pattern androgenetic alopecia patents, female-pattern androgenetic alopecia patients, and alopecia areata patients, respectively (left picture in the drawings shows the head before laser process, and right picture shows the head after the laser process). Accordingly, it can be confirmed that the hair growth was improved by the high-power fractional laser process according to the present invention.

While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims.

Claims

[CLAIMS] [Claim 1]

A device for stimulating hair growth using a fractional optical pulse, comprising: an optical pulse generation unit for generating and outputting an optical pulse; an optical pulse transfer unit, coupled to the optical pulse generation unit, for guiding the optical pulse outputted from the optical pulse generation unit; a handpiece, coupled to the optical pulse transfer unit, for irradiating laser beams onto scalp to be operated; and a divided beam irradiation unit, provided in the handpiece, for dividing the optical pulse transferred from the optical pulse transfer unit into a plurality of fractional beams and simultaneously irradiating the divided fractional beams onto the scalp to be operated.

[Claim 2]

The device of claim 1, wherein the optical pulse is a laser beam pulse.

[Claim 3]

The device of claim 2, wherein the diameter of the fractional beam is in the unit of micrometers (μm).

[Claim 4]

The device of any one of claims 1 to 3, wherein the divided beam irradiation unit is a micro-lens array having a plurality of micro-lenses for making the laser beams focused within the scalp.

[Claim 5]

The device of claim 4, wherein the diameter of the fractional beam is in the range of 50 to 500μm.

[Claim 6]

The device of claim 5, wherein alight source of the optical pulse generation unit is at least one selected from a group composed of a diode laser, a diode pump type solid-state laser, an Er (Erbium):YAG (Yttrium Aluminum Garnet) laser, a Nd (Neodymium):YAG laser, an Er÷glass laser, an argon ion laser, a helium-neon laser, a CO₂ gas laser, an excimer laser, a fiber laser, a ruby laser, and a frequency multiplied laser.

[Claim 7]

A device for stimulating hair growth using a fractional optical pulse, comprising: an optical pulse generation unit for generating and outputting an optical pulse; an optical pulse transfer unit, coupled to the optical pulse generation unit, for guiding the optical pulse outputted from the optical pulse generation unit; a handpiece, coupled to the optical pulse transfer unit, for irradiating laser beams onto scalp to be operated; a scanner, provided in the handpiece, for making and irradiating fractional beams by successively irradiating the optical pulse transferred from the optical pulse transfer unit in different directions! and a condensing lens for condensing the fractional beams irradiated from the scanner so that the fractional beams are focused within the scalp.

[Claim 8]

The device of claim 7, wherein the optical pulse is a laser beam pulse.

[Claim 9]

The device of claim 8, wherein the size of the fractional beam outputted from the condensing lens is in the unit of micrometers (μm).

[Claim 10]

The device of any one of claim 7 to 9, wherein the scanner irradiates the fractional beams in random directions in the range of an area of a handpiece tip that is a front end of the handpiece.

[Claim 11]

The device of claim 10, wherein the diameter of the fractional beam irradiated onto the scalp is in the range of 50 to 500μm.

[Claim 12] The device of claim 11, wherein a light source of the optical pulse generation unit is at least one selected from a group composed of a diode laser, a diode pump type solid-state laser, an Er (Erbium) :YAG (Yttrium Aluminum Garnet) laser, a Nd (Neodymium):YAG laser, an Er:glass laser, an argon ion laser, a helium-neon laser, a CO2 gas laser, an excimer laser, a fiber laser, a ruby laser, and a frequency multiplied laser.

[Claim 13]

A method for stimulating hair growth using a fractional optical pulse, comprising performing a fractional process of an optical pulse and irradiating the fractionally processed optical pulse to scalp to be operated.

[Claim 14]

The method of claim 13, wherein the optical pulse is a laser beam pulse.

[Claim 15]

The method of claim 14, wherein the laser beam pulse is divided into a plurality of fractional laser beams and the divided fractional laser beams are simultaneously irradiated onto the scalp so that the fractional laser beams are focused within the scalp.

[Claim 16]

The method of claim 15, wherein the diameter of the fractional laser beam is in the unit of micrometers (μm).

[Claim 17]

The method of claim 16, wherein the diameter of the fractional laser beam is in the range of 50 to 500μm.

[Claim 18]

The method of claim 14, wherein the fractional laser beams are generated through successive irradiation of the laser beam pulse in different directions, and then are condensed and irradiated onto the scalp to be operated so that the generated fractional laser beams are focused within the scalp.

[Claim 19] The method of claim 18, wherein the diameter of the condensed laser beam is in the unit of micrometers (μm).

[Claim 20]

The method of claim 19, wherein the diameter of the condensed laser beam is in the range of 50 to 500/zm.

[Claim 21]

The method of any one of claims 14 to 20, wherein the fractional laser beam has a wavelength of 400 to 12,000nm, energy per area of 0.001 to 100,000

2

J/cm , energy per wave of 5OmJ and less, and pulse duration of 100ms and less.

[Claim 22]

The method of claim 21, wherein the density of the fractional laser

2 beam is in the range of 100 to 3,000 pieces/cm .

[Claim 23]

The method of claim 22, wherein the fractional laser beam stimulates an area of the scalp that has a depth of 10 to 4,000/M and the diameter of 10 to 1,000/an.