Hair modification using converging light

• US 20070005047A1
• Filed: 06/29/2005
• Published: 01/04/2007
• Est. Priority Date: 06/29/2005
• Status: Active Grant

• Current Assignee: Gearbox LLC (Intellectual Ventures LLC)
• Original Assignee: Searete LLC (Intellectual Ventures LLC)
• Inventors: Ferren, Bran, Jung, Edward, Tegreene, Clarence, Myhrvold, Nathan, Wood, Lowell, Ishikawa, Muriel
• Granted Patent: US 9,055,958 B2
• Time in Patent Office: Days
• US Class Current: 606/9
• CPC Class Codes: A61B 18/203 applying laser energy to the outside of the body
• CPC Class Codes: A61B 2018/00452 Skin
• CPC Class Codes: A61B 2018/00476 Hair follicles

Abstract

Embodiments of methods and systems for hair treatment are disclosed. According to various embodiments, light is used to shave, trim, or otherwise modify hair shafts.

Claims

1. A method of modifying hair on a skin surface, comprising:

a) positioning at least one light source activatable to produce highly convergent light substantially adjacent to the skin surface;

b) determining a distance of said at least one light source from the skin surface; and

c) if said determined distance is within a specified range, activating said at least one light source to generate the highly convergent light for a duration and with an intensity sufficient to cause modification of at least one hair shaft growing from the skin surface.

2. The method of claim 1, wherein said at least one light source comprises a laser, a laser diode, or a light-emitting diode.

3. The method of claim 1, wherein activating said at least one light source to generate convergent light includes activating at least one light source to generate a convergent beam having a short, narrow beam waist.

4. The method of claim 1, wherein activating said at least one light source to generate convergent light includes activating two or more light sources to generate two or more beams that converge on a high fluence overlap region.

5. The method of claim 3, wherein activating the light source to generate the highly convergent beam includes forming a beam waist of the highly convergent beam just above the skin surface.

6. The method of claim 3, including generating a beam having an angle of convergence of between about 10 and about 80 degrees relative to the axis of said beam.

7. The method of claim 3, including generating a beam having an angle of convergence of between about 25 and about 70 degrees relative to the axis of said beam.

8. The method of claim 3, including generating a beam having an angle of convergence of between about 45 and about 55 degrees relative to the axis of said beam.

9. The method of claim 1, wherein activating said light source includes receiving an activation command from a user of said device and activating said at least one light source in response to said activation command.

10. The method of claim 1, wherein activating said light source includes activating said at least one light source automatically when said determined distance is within said specified range.

11. The method of claim 3, including generating a beam in which the diameter of said beam at the skin surface is between about 2 and about 10 times the diameter of said beam at said beam waist.

12. The method of claim 3, including generating a beam having a beam waist positioned between about 1 and about 3 hair diameters above the skin surface.

13. The method of claim 3, including generating a beam having a beam waist positioned between about 25 μ

m and about 300 μ

m above the skin surface.

14. The method of claim 3, including generating a beam having a beam waist diameter of between about 1 and about 3 hair diameters.

15. The method of claim 3, including generating a beam having a beam waist diameter of between about 17 μ

m and about 600 μ

m.

16. The method of claim 3, including generating a beam having a beam waist diameter of between about 25 μ

m and about 300 μ

m.

17. The method of claim 3, including generating a beam having a beam waist diameter of between about 50 μ

m and about 100 μ

m.

18. The method of claim 3, including detecting the presence of a hair shaft in the vicinity of the skin surface and activating said light source so to generate said highly convergent beam with said narrow beam waist located near the base of said hair shaft.

19. The method of claim 1, including controlling said duration and intensity to produce bleaching of at least a portion of said hair shaft.

20. The method of claim 1, including controlling said duration and intensity to produce mechanical damage to at least a portion of said hair shaft.

21. The method of claim 1, including controlling said duration and intensity to produce severing of said hair shaft.

22. The method of claim 1, wherein said beam waist is moved over the general region of the skin surface containing the hair shaft but is not specifically targeted to the hair shaft.

23. A depilation method comprising:

delivering light to a skin region to be depilated with at least two light sources, said at least two light sources aimed so that light from said light sources overlaps spatially at an overlap region located at a distance above the skin surface, wherein light fluence at said overlap region is sufficient to cause mechanical failure of a hair within said overlap region and wherein light from said at least two light sources striking the skin surface is sufficiently non-overlapping that the light fluence at the skin surface is below the threshold for causing tissue damage or irritation.

24. The depilation method of claim 23, including delivering light to said skin region through a light-conducting medium interposed between said light source and said skin surface.

25. The depilation method of claim 24, wherein said medium is a light activated medium.

26. The depilation method of claim 24, wherein said medium has an index of refraction significantly different than the index of refraction of air.

27. The depilation method of claim 23, wherein light fluence at said overlap region is sufficient to cause absorption of between about 50 and about 200 Joules per gram by a hair at said overlap region.

28. The depilation method of claim 23, wherein light fluence at said overlap region is sufficient to cause absorption of between about 50 and about 100 Joules per gram by a hair at said overlap region.

29. A depilation system comprising:

a) at least two light sources arranged to generate light beams that converge spatially to overlap at an overlap region and subsequently diverge spatially to form a non-overlap region;

b) a sensor capable of detecting the position of said least two light sources relative to a skin surface to be depilated; and

c) a controller configured to activate said at least two light sources when said at least two light sources are positioned relative to the skin surface such that said overlap region is located above the skin surface and said skin surface lies within said non-overlap region.

30. The depilation system of claim 29, wherein said controller includes a microprocessor.