HAIR ABLATION SYSTEM BY OPTICAL IRRADIATION FIELD OF THE INVENTION The present invention pertains to shaving systems. More particularly, the present invention pertains to shaving systems which incorporate optical filters that selectively direct high intensity light into a field, but only onto the objects in the field which are to be photoablated. The present invention is particularly, but not exclusively, useful for shaving hair from the body surface of a person.
BACKGROUND OF THE INVENTION
Shaving hair from the body has been practiced by men and women since near the beginning of recorded time. Indeed, in many respects the instruments which are used today for this purpose still bear some rudimentary resemblance to the earlier shaving instruments. Specifically, both ancient shaving devices and modern day shaving devices have somehow generally included a sharpened edge, or blade, which is used to cut the hair close to the surface of the skin to give the person a shaven appearance. Over the years, improvements in shaving devices have been mostly the result of learning new and better ways to use more durable materials in the manufacture of longer lasting and sharper blades for the devices. Modern technology, however, has taken us to the point where we are now looking for alternative ways to more efficiently and conveniently shave ourselves. Such attempts, as is the case with the present invention, have focused on ways of severing hair from the body which are quite different from merely cutting the hair with a blade. It is well known that many materials can be altered by a process which is generally referred to as photoablation. For photoablation, photons from a high intensity light source, such as a laser, are focused onto a material to alter the material in a way which causes it to be cut or severed. This result may, of course, be beneficial for diverse applications and the intent here is not to limit the present invention to a single such application. Instead, the present invention pertains to all applications where it is necessary and essential to carefully control the photoablation process. One specific instance involves applications where human tissue is to be cut or severed.
It happens that photoablation is quite effective as a procedure for altering human tissue. As implied above, however, where human tissue is involved it is essential to effectively control the photoablation process. In essence this means that the light used for photoablation needs to be carefully and accurately focused onto only the specific area or part of the material or tissue which is to be cut or severed. The present invention recognizes this can be accomplished by properly filtering the light which is used to photoablate the material.
Accordingly, it is an object of the present invention to provide a device for photoablating objects, such as human hair, which focuses sufficient light energy onto the object to cut or sever the object. Another object of the present invention is to provide a device for photoablating objects which selectively focuses high intensity light only onto objects which are framed within a field. Still another object of the present invention is to provide a device for photoablating objects which filters or blocks unwanted energy from a high intensity light source to selectively direct light onto objects which are to be altered by photoablation. Yet another object of the present invention is to provide a device for photoablating objects which is easy to use, relatively simple to manufacture and comparatively cost effective.
SUMMARY OF THE INVENTION In accordance with the present invention, a shaving device for photoablating hair includes a source of high intensity light, such as a laser, which is operationally connected to the optical system of the device. This optical system includes an aperture, a filter device and an optical system. All of which may be mounted together in a housing. When properly mounted, the optical system of the present invention is positioned between the aperture and the filter. More specifically, in relation to the optics established by the optical system, the aperture is located in the object plane, and the filter is located in the image plane. Consequently, when objects, such as strands of hair, are framed in the aperture, the picture composed by the object in the aperture is transferred through the optical system and onto the filter in the image plane.
The device of the present invention also includes a secondary light source which is positioned to illuminate objects as they are framed by the aperture and the filter. The picture which results from this illumination by the secondary light source is then transferred through the optical system as mentioned above, to the filter where a negative of the picture is created to effectively establish a negative filter. High intensity light, e.g. a laser light, is then directed from the high intensity light source, through the negative filter and onto the objects framed by the aperture. In one embodiment of the present invention the filter device is an element having an image recording medium which, in response to light from the secondary source that is reflected by the object, establishes a negative of the picture. This embodiment can include a tertiary light source which radiates light at a wavelength that will erase the negative from the image recording medium of the filter. Alternatively, instead of a tertiary light source, a voltage source can be included which will erase the negative from the image recording medium at intervals as the picture changes. For another embodiment of the present invention, the filter device incorporates an image processor which receives light from the secondary source that is reflected by the object to generate a signal which is representative of a negative picture. This signal is then used to impact the high intensity light source. In turn, the high intensity light source is programmed to accurately and selectively direct a beam of high intensity light onto only the objects that are to be photoablated.
In the operation of the particular embodiment for the present invention which uses an image recording medium as the filter, the secondary light source is first activated to create the negative at the filter, the high intensity light source is then activated to use the negative filter for directing light onto the object to be ablated, and the negative is then erased. This sequence can be repeated as necessary. In the operation of the embodiment of the present invention which uses an image processor as a filter, the secondary light source and the high intensity light source are alternatingly activated, as necessary.
For the particular application where the device of the present invention is to be used as a shaving system, the aperture can be mounted in a housing and the housing can be attached to a handle which can be used to move the aperture across the surface to be shaved. The optical. system and the negative filter can also be mounted in the housing or, through the use of a suitable optical fiber system, can be mounted as a remote unit. Similarly, the various light sources can be remotely mounted as desired.
The novel features of this invention, as well as the invention itself, both as to its structure and its operation will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: BRIEF DESCRIPTION OF THE DRAWINGS Figure IA is a perspective view of the device of the present invention being used in an intended environment with a remote unit; Figure IB is a perspective view of an alternate embodiment of the device of the present invention in a cordless configuration without a remote unit;
Figure 2 is a perspective view of the device; Figure 3 is a cross sectional view of the housing of the device as seen along the line 3-3 in Figure 2;
Figure 4 is a perspective view of an optical system for focusing light;
Figure 5 is a perspective view of the optical system of the present invention forming a positive photographic image;
Figure 6 is a perspective view of the optical system of the present invention with the negative filter established for operational use with a high intensity light source; Figure 7 is a schematic diagram of the operative components of the present invention for an embodiment which incorporates a voltage source to erase an image recording medium;
Figure 8 is a schematic diagram of the operative components of the present invention for another embodiment which incorporates a tertiary light source to erase an image recording medium; and
Figure 9 is a schematic diagram of the operative components of the present invention for still another embodiment which incorporates an image processor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring initially to Figure IA, a device for photoablating an object is shown in an intended environment and is generally designated 10. As shown in Figure IA, the device 10 is being used to shave facial hair. This application, however, is not limiting.
In Figure IA, the device 10 is shown to include a razor 12 which is operatively connected by a cable 14 to a remote unit 16. Further, it can be seen that the remote unit 16 is formed with a cradle 18 which is formed to receive and hold the razor 12 when the razor 12 is not in use. With this device 10, a user 20 can remove the razor 12 from the cradle 18 of remote unit 16, and activate the unit 16 to shave hair from a body surface. In an alternate preferred embodiment of the present invention, as shown in figure IB, the device 10 is shown in a cordless configuration. In this alternate embodiment, the cable 14 and remote unit 16 are eliminated and instead, all operative components of the device 10 are housed in the razor 12.
A more detailed view of the razor 12 of device 10 is presented in Figures 2 and 3. In Figure 2, specifically, it is shown that the razor 12 comprises a housing 22 and a handle 24 which is integrally attached to the housing 22. Although housing 22 is integral with the handle 24 for the embodiment shown in Figures 1-3, it will be appreciated that several forms of attachment between the housing 22 and the handle 24 can be established for the purposes of the present invention. Further, in Figures 1 and 2 the cable 14 is shown to extend from the handle 24. Again, there can be several ways in which razor 12 is connected with the remote unit 16. Importantly, Figures 2 and 3 also show that the housing 22 is formed with an aperture 26 that is both long and narrow. Stated differently, the aperture 26 is formed as a slit which has great width and very little height.
The relationship between the housing 22 of razor 12 and the operative optical elements of the device 10 are, perhaps, best shown in Figure 3. There it will be seen that the housing 22 is formed with an aperture 26 at its front, and that a negative filter element 28 is positioned near the rear of the housing 22. As indicated in Figure 3, a series of lenses are positioned in the housing 22 for the purpose of transferring light between the aperture 26 and the negative filter 28. Specifically, this series of lenses includes, in sequence from the aperture 26 to the negative filter 28, a cylindrical lens 30, a relay lens 32 and a cylindrical lens 34. Together, the lenses 30, 32 and 34 comprise the optical system 36 of the device 10. A preferred configuration for this optical system 36 for the device 10 is best seen in Figures 5 and 6. When considering this configuration, it is to be appreciated that the relay lenses 32 can be positioned in any convenient arrangement which will effectively transfer light between the cylindrical lenses 30 and 34. For example, instead of positioning the negative filter 28 in the housing 22 of razor 12, it is conceivable that the negative filter 28 be positioned in the remote unit 16 of the device 10. The determining element in each case will be the configuration and composition of the relay lens 32. Regardless of the particular configuration for the relay lens 32, it is important for the operation of the device 10 that the optical system 36 be configured so that its object plane is coincident with the aperture 26 and its image plane is coincident with the negative filter 28.
Figure 4 illustrates a typical lens configuration whereby high intensity light, such as a laser, can be focused for the purpose of photoablating an object. For this illustrated configuration the light is shown linearly focused. Specifically, a beam of high intensity light 38 is first directed through a converging cylindrical lens 40. The converging cylindrical lens 40 then confines the beam 38 onto a transfer element 42. As is well known in the art, this transfer element 42 can be any suitable structure, such as an optical fiber system, which is capable of effectively transferring light from one point to another. For . the typical lens configuration being discussed, a dispersion lens 44 is shown to spread the light in beam 38 from the dispersion lens 44 and onto an elongated cylindrical lens 46. The cylindrical lens 46 then linearly focuses the light to establish a cutting edge 48. For such a configuration, it is possible to focus the high intensity light beam 38 such that the established cutting edge 48 is only approximately one to two microns in thickness (1-2 microns) , and has a depth of focus which is less than approximately one half millimeter (0.5 mm) . For the purposes of the present invention, the optical system 36 incorporates similar optics.
Importantly for the present invention, depending on the direction in which light traverses the optical system 36, the system 36 linearly focuses light on either the object plane at the aperture 26, or on the image plane at the negative filter 28. In order to do this, the cylindrical lenses 30 and 34 are located at the opposite ends of the optical system 36, as shown in Figures 5 and 6. As indicated above, the relay lenses 32a,b can be of any type well known in the art.
With a configuration as shown for the optical system
36 in the Figures 5 and 6, whenever aperture 26 is positioned against objects 50 a,b and c (for example, hair) the objects 50 a,b and c are framed by the aperture 26.
This framing creates a picture which includes the objects
50 a,b and c, as well as the spaces 52 a,b,c and d that appear around the objects 50. This picture is then transferred through optical system 36 by light 54 to be recomposed on the image plane of optical system 36 at negative filter 28. As will be appreciated by the skilled artisan, a negative of the picture, as framed at the aperture 26, will invert the dark and the light portions of the picture to make the picture appear as shown at the negative filter 28' in Figure 6. More specifically, objects 50 a,b and c which appear dark in aperture 26 will appear as light objects 50 a»,b' and c' at the negative filter 28'. Conversely, the light spaces 52 a,b,c and d which appear at aperture 26 will appear as dark spaces 52 a^b^c'and d1 at the negative filter 28'. The transformation of negative filter 28 into a negative of the picture of the objects 50 a,b and c framed by aperture 26 can be accomplished by components known in the art, in a manner to be subsequently discussed. Suffice for the moment that the negative filter 28' can be created by the light 54 reflected from aperture 26 through the optical system 36.
Once the negative filter 28' has been established in response to the reflected light 54, high intensity light 56 can be directed through the filter 28• and focused by the cylindrical lens 30 of optical system 36 onto the objects 50 a,b and c. Importantly, due to the filtering effect which the negative filter 28' has on light 56, the light 56 will be blocked from passing through the spaces 52 a,b,c and d at aperture 26 and will be focused on only the objects 50 a,b and c. Consequently, when light 56 is focused in a manner as discussed above with reference to Figure 4, and depending on the wavelength of the light 56 and its ability to interact with the material of which the objects 50 a,b and c are composed, the objects 50 a,b and c will be photoablated.
Several structural embodiments for establishing the negative filter 28' and for directing high intensity light 56 onto the objects 50 a,b and c to be photoablated are contemplated for the device 10. For example. Figure 7 shows the schematic of an embodiment for device 10 wherein the filter 28 includes an image recording medium that is responsive to light 54 to create the negative filter 28'. Several media, such as a liquid crystal or solid crystal display of any type well known in the pertinent art, can be used for this purpose. Indeed, any reversible and erasable crystalline recording medium can be used for this purpose. For the particular embodiment shown in Figure 7 a high intensity light source 58 is provided as well as a secondary light source 60 and a voltage source 62. Also included is a beam splitter 64 which, as shown in Figure 7, can be incorporated into the structure of the optical system 36 in a manner well known in the pertinent art.
In the operation of the structural embodiment shown in Figure 7, light from the secondary light source 60, is directed along a light path 66 toward the beam splitter 64 where it is directed onto the optical axis 68 of the optical system 36 and toward the aperture 26. This light is then reflected from objects 50 a,b,c and aperture 26 as the light beam 54. For purposes to be subsequently discussed, the beam of light 54 has a wavelength that is different from that of the high intensity light 56. Furthermore, the wavelength of the light 54 must be properly selected to be capable of creating a negative at the filter 28• .
After filter 28* has been established by the light beam 54 which originated at secondary light source 60, the high intensity light source 58 is activated. With the activation of high intensity light source 58, high intensity light 56 is directed along a beam path 70 and through negative filter 28' . After being filtered at the negative filter 28* the high intensity light is passed along the optical axis 68 of optical system 36 to be focused through aperture 26 and into the cutting edge 48. With aperture 26 adjacent the objects 50, only those parts of cutting edge 48 are activated with focused high intensity light that coincides with the objects 50 a, b and c. The objects 50 are thus photoablated.
As shown in Figure 7, the voltage source 62 is connected via electrical conductor 72 with the negative filter 28. For this embodiment of the- device 10, the voltage source 62 is appropriately activated to erase the negative filter 28' after secondary light source 60 is activated to establish the filter 28' and after high intensity light source 58 has used the negative filter 28' to direct high intensity light 56 onto only the objects 50. With the erasure of filter 28' the voltage source 62 prepares filter 28 for the creation of a new negative filter 28'. The new negative filter 28' will, of course, be characteristic of the new picture presented as aperture 26 is placed adjacent new objects 50. As indicated, secondary light source 60, high intensity light source 58 and voltage source 62 are each activated in the ordered sequence described above to photoablate the objects 50. The sequence can be repeated as necessary, and the time interval in each cycle during which high intensity light source 58 is activated is preferably less than ten milliseconds (10 msec) .
For the embodiment of device 10 shown in Figure 7, both beam path 66 and beam path 70 can be made of an optical fiber system of any type well known in the pertinent art. Consequently, beam paths 66 and 70 can be combined with the electrical connector 72 as components of the cable 14 which connects remote unit 16 with razor 12. In this configuration, the high intensity light source 58, the secondary light source 60 and the voltage source 62 can be mounted in the remote unit 16. Of course, for the alternate embodiment of device 10 shown in Figure IB, the same optical fiber system can be used with the high intensity light source 58, the secondary light source 60 and the voltage source 62 mounted on razor 12. This embodiment thus eliminates the need for cable 14 and remote unit 16. Indeed, as indicated above, the operative elements in each of the various embodiments for the device 10 can be mounted on razor 12.
In another embodiment of the present invention, as shown in Figure 8, a combined light source 74 is' used which includes the high intensity light source 58 in combination with a tertiary light source. Again, an image recording medium, such as the filter 28 is used. Also, the secondary light source 60 is still included, and it performs substantially the same function in substantially the same way as disclosed for the secondary light source 60 in Figure 7. The voltage source 62, however, is eliminated. Instead, the tertiary light source of combined light source 74 is used to erase the negative 28* to prepare filter 28 for the creation of a new negative filter 28• . Necessarily, the wavelength of light from the tertiary source must be different from the wavelengths of the light from both the secondary source 60 and the high intensity light source 58. Furthermore, while light from secondary source 60 must be capable of converting filter 28 into filter 28', light from the tertiary source must be capable of erasing the filter 28* and converting it back into the filter 28.
In the operation of the embodiment for device 10 as shown in Figure 8, the secondary light source 60 is activated to direct light 54 along the optical axis 68 to establish negative filter 28' . High intensity light source 58 is then activated to direct the light beam 56 through the negative filter 28' and along optical axis 68 to be focused through aperture 26 onto cutting edge 48. Thus, only beams of light 56 which have passed through negative filter 28', and which therefore correspond with objects 50, will be focused onto cutting edge 48 to photoablate the objects 50. The tertiary light source is then activated to erase the filter 28' and the sequence is repeated as necessary. Preferably, the time interval during which high intensity light source 58 is activated during any one cycle of the sequence will be less than ten milliseconds (10 msec) . Additionally, as will be appreciated by the skilled artisan, the high intensity light source 58 and the tertiary light source can be separated, rather than being integrated into the combined light source 74. Figure 9 shows yet another embodiment of the device 10 wherein the filter 28 comprises an image processor, such as a charge couple device well known in the pertinent art. For this embodiment, a microprocessor 76 is electrically connected to both the image processor of filter 28 via an electrical connection 78 and to a combined light source 80. In this instance, the combined light source 80 includes both the high intensity light source 58 and the secondary light source 60. Light from the combined light source 80 is directed onto the optical axis 68 of optical system 36 via optical path 82 and a beam splitter 84.
In the operation of the embodiment shown in Figure 9, the combined light source 80 is energized to first activate the secondary light source 60. As disclosed above, light 54 from the secondary light source 60 establishes the negative filter 28'. The image processor of filter 28 then creates electrical signals that are representative of the negative filter 28' which corresponds to a picture of objects 50 framed by the aperture 26. Next, these signals are processed by the microprocessor 76 which, in turn, activates the high intensity light source 58. The resultant beam of high intensity light 56 from the combined light source 80 is configured to correspond with negative filter 28' and is passed through the optical system 36 to be focused onto cutting edge 48. Consequently, because the light 56 is configured to correspond with negative filter 28', the light 56 is focused on cutting edger 48 only where there are objects 50
In the operation of the embodiment shown in Figure 9, the high intensity light source 58 and the secondary light source of combined light source 80 are alternatingly activated by the microprocessor 76. Specifically, after secondary light source 60 has been activated to create the negative filter 28' , the high intensity light source 58 is activated to generate a light beam 56 which corresponds with the negative filter 28' . With the light beam 56 the objects 50 are photoablated. As implied, this sequence can be repeated as necessary or desired. Preferably, the time interval in each sequence during which high intensity light source 58 is activated is, as with the other embodiments disclosed above, less than ten milliseconds in duration (10 msec) . Further, it will be appreciated by the skilled artisan that high intensity light source 58 and secondary light source 60 need not be combined into combined light source 80 but can, instead, be separated as desired.
While the particular device for photoablating objects as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of the construction or design herein shown other than as defined in the appended claims.