IL105060A - Hair cutting apparatus - Google Patents

Description

ni7'A τκοη HAIR CUTTING APPARATUS 1Π7|7 UP7X ELLIOT KELMAN C: 16265 16265S02 I-948A HAIR CUTTING APPARATUS FIELD OF THE INVENTION The present invention relates to hair cutting apparatus generally and more specifically to improved laser hair cutting devices .

BACKGROUND OF THE INVENTION There exists a great variety of hair cutting apparatus. These include single or multiple blade razors which are pulled across the surface of the skin and devices having an electrically powered vibratory element which drives opposing blades in a scissors type action.

U.S. Patent 3,934,115 describes a method and apparatus for electric singe cutting in which heated and opposed edges of two thin strips of metal form a slot, at which hair extending therethrough is singed to effect severance of the hair.

WO 91/06406 describes a system in which laser light is used to cut human hair. The incoming laser beam makes an angle of nearly 90 degrees with the surface of the skin.

U.S. Patent 4,578,558 describes a system for severing removing fell from a fabric using a scanning laser.

U.S. Patent 4,051,760 describes a device for removing hair from an animal. The main embodiment is of a hot wire type hair cutter. While the use of a laser is mooted, no details of its application are described.

U.S. Patent 4,819,669 describes a system for cutting human hair using laser energy to singe hair by applying energy to the top of the hair and applying it over the entire length of hair. 16265S02 I-948A SUMMARY OF THE INVENTION The present invention seeks to provide improved hair cutting apparatus .

There is thus provided in accordance with a preferred embodiment of the present invention, hair cutting apparatus including a housing and laser apparatus disposed in the housing and arranged to provide a beam of light preferably in the infrared, more preferably having a wavelength of between about 3 and 3.5 micrometers or between about 6 and 9 micrometers impinging on hair to be cut. Alternatively, infra-red energy having a wavelength of 1.05 micrometers is also useful in the practice of at least some aspects of the invention.

In accordance with a preferred embodiment of the present invention, the laser apparatus also comprises optical transfer means for directing the beam to the hair. The optical transfer means may include refraction or reflection means having optical power .

Additionally in accordance with a preferred embodiment of the invention, hair collection apparatus may also be provided in the housing for collecting loose hairs that have been cut by the laser beam. The hair collection apparatus may comprise a vacuum device or, alternatively or additionally, electrostatic hair collection apparatus.

In accordance with a preferred embodiment of the invention, the beam of light has a power output of less than 10 watts, more preferably between 3 and 5 watts.

There is further provided in accordance with a preferred embodiment of the invention, hair cutting apparatus including a housing and laser apparatus disposed in the housing and arranged 16265S02 I-948A to provide a beam of light impinging on hair to be cut in a hair cutting region and also including a detector for detecting the intensity of the light after it passes through the cutting region.

In a preferred embodiment of the invention, the hair cutting apparatus includes apparatus, responsive to the detector, for adjusting the intensity of light which is supplied.

Additionally, the apparatus preferably provides laser light at a first, high power, level when the output of the detector indicates that there is hair in the hair cutting region and at a second, low power, level when the output of the detector indicates that there is no hair in hair cutting region.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which: Fig. 1A is a pictorial illustration of the use of a shaver constructed and operative i accordance with a preferred embodiment of the present invention; Fig. IB is a pictorial drawing of the use of a hair cutting device constructed and operative in accordance with a preferred embodiment of the invention; Fig. 2A is a simplified sectional illustration of a laser shaver constructed and operative in accordance with a preferred embodiment of the present invention.

Fig. 2B is a simplified sectional illustration taken along the lines 2B - 2B of Fig. 2A; Fig. 3A is a simplified sectional illustration of a laser shaver constructed and operative in accordance with another 16265S02 I-948A preferred embodiment of the present invention; and Fig. 3B is a simplified sectional illustration taken along the lines 3B - 3B of Fig. 3A.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Reference is now made to Figs. 1A, 2A and 2B which illustrate a laser shaver constructed and operative in accordance with a preferred embodiment of the present invention. The laser shaver preferably comprises a housing 10, typically formed of plastic or of any other suitable material. Disposed within housing 10 is laser apparatus 12, preferably comprising a laser source 14 and laser beam transfer optics 16, which direct a laser beam 18, produced by the laser source 14 to hairs 19 to be cut. The hairs to be cut enter housing 10 through a screened slot, similar to those in an electric shaver, having a length of, preferably, 50 mm and a width of, preferably, 12 mm.

In accordance with a preferred embodiment of the present invention, the laser source 14 comprises a semiconductor laser such as a diode or a switched ruby laser, preferably operative to provide an output laser beam at a wavelength which is strongly absorbed by hair, such as facial hair. It has been found that melanin in hair absorbs energy in the infra-red, specifically at wavelengths between 3 and 3.5 microns and between 6 and 9 microns, although other infra-red wavelengths such as 1.05 microns is also useful in the practice of the invention. A preferred power level for these wavelengths is less than 10 watts, more preferably between 3 and 5 watts.

It is a feature of some aspects of the present invention that suitable selection of the operative wavelength of the laser source 14 enables hair to be vaporized and carbonized at the 16265S02 I-948A location of impingement of the laser beam 18 thereon, thus separating that portion of the hair still attached to the hair follicle from that extending outward from the impingement location, thereby producing a hair cutting effect. At these wavelengths the power level required is less than that required at other, less absorbed wavelengths. Also, the amount of absorption is relatively independent of the hair color.

The laser beam transfer optics 16 preferably comprise reflective optics, such as a mirror 20 and refractive optics such as a lens 22. Any other suitable arrangement of laser beam transfer optics 16, including any suitable optical element or elements may alternatively be employed.

In accordance with one preferred embodiment of the present invention, there is also provided a laser beam absorber 30 for absorbing the laser beam and thus preventing spurious impingements thereof.

Reference is now made to Figs. 3A and 3B which illustrate a preferred embodiment of laser shaver in which the laser beam transfer optics is designed to provide multiple reflections of the laser beam over a shaving region. In this case, the absorber 30 is replaced by at least two mirrors 32 and preferably a generally rectangular circumferential mirror assembly which is operative to provide a back and forth pattern of laser beams, which can be effective for cutting hair over a relatively large area. It is appreciated that in this embodiment, initial impingement of the laser beam on mirror 20 is such as to produce a reflection which is not perpendicular to the planes of mirrors 32. Preferably the laser beams have a wavelength in the infrared, more preferably they have a wavelength of 3-3.5 micrometers 16265S02 I-948A or 6-9 micrometers.

In a preferred embodiment of the invention, an absorber 30' is placed at the end of the path of the laser beam. Absorber 30' absorbs any laser light which was not absorbed by light in the region between the mirrors.

In a preferred embodiment of the invention, a partial silvered mirror 33 intercepts a portion of the beam at the end of its travel through the region in which hair is cut and causes it to impinge on a detector 34. The output of detector 34 is fed to a control portion of power supply 26 for control of the power output of the laser source.

When no hair is present in the hair cutting region and the laser power is high, the output of detector 34 is high. This high output signal indicates to the control portion that there is no hair presently being cut, and the control portion reduces the power output of laser source 14 to a standby value. When hair enters the hair cutting region during the standby mode, the detector output drops further, and the control portion increases the power level of the laser to a value suitable for cutting hair. Thus, by measuring the absorption of laser light in the hair cutting region, the system automatically produces a high energy beam when such a beam is required for cutting hair and a low energy beam suitable for monitoring the light intensity when there is no hair being cut.

While the invention has been described with specific beam directing apparatus, the present invention is also applicable to a system in which the beam is scanned across the hair cutting region by a oscillating mirror, polygon laser scanner or other scanner . 16265S02 I-948A According to a preferred embodiment of the present invention, there is provided apparatus for collecting loose hairs, which are cut by the impingement thereon of laser beam 18. The apparatus for collecting loose hairs preferably comprises electrically operated vacuum apparatus 24, such as a suction blower but may alternatively comprise any other suitable hair collection apparatus, such as electrostatic apparatus.

Both the laser source 12 and the vacuum apparatus may receive electrical power from a suitable power supply 26, which may be battery powered or alternatively powered by an external source of current.

It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather the scope of the present invention is defined only by the claims which follow:

Claims (11)

16265S02 I-948A C L A I M S

1. Hair cutting apparatus comprising a housing and laser means disposed in the housing and arranged to provide a beam of light impinging on hair to be cut in a hair cutting region, the beam of light having a wavelength in the infra-red.

2. Hair cutting apparatus according to claim 1 wherein the wavelength is between 3 and 3.5 micrometers or between 6 and 9 micrometers .

3. Hair cutting apparatus according to claim 1 wherein the wavelength is approximately 1.05 micrometers.

4. Hair cutting apparatus comprising: a housing; a laser disposed in the housing and arranged to provide a beam of light impinging on the hair to be cut in a hair cutting region; and a detector for detecting the intensity of the beam of light after it passes through the hair cutting region.

5. Hair cutting apparatus according to any of claims 1-3 and comprising a detector for detecting the intensity of the beam of light after it passes through the hair cutting region.

6. Hair cutting apparatus according to any of the preceding claims and wherein said laser means also comprises optical transfer means for directing the beam to the hair. 16265S02 I-948A

7. Hair cutting apparatus according to claim 6 and wherein said optical transfer means includes refraction and reflection means having optical power.

8. Hair cutting apparatus according to claim 6 or claim 7 wherein said optical transfer means comprise means for focusing said laser beam.

9. Hair cutting apparatus according any of the preceding claims and including at least two mirrors for causing multiple reflections of the light beam within the hair cutting region.

10. Hair cutting apparatus according to any of the preceding claims and also comprising hair collection means in the housing for collecting loose hairs that have been cut by the laser beam.

11. Hair cutting apparatus according to claim 10 and wherein said hair collection means comprises a vacuum device. C:16265