Method and device for skin treatment using laser diode bars emitting different laser wavelengths

Abstract

A method and device for skin treatment include using a laser diode bar stack to generate a mix of at least two laser wavelengths for application to a skin area to be treated.

Claims

1. A device for skin treatment comprising: a hand piece having a laser diode bar stack, the laser diode bar stack including at least one first laser diode bar configured to emit a first laser wavelength and at least one second laser diode bar configured to emit a second laser wavelength, the first and second laser wavelengths being different, and a delivery mechanism configured to convey the first and second laser wavelengths to a skin area to be treated; wherein the laser diode bar stack includes respective pluralities of the first and second laser diode bars; and wherein multiple bars of the plurality of first laser diode bars alternate with at least one bar of the plurality of second laser diode bars.

2. The device of claim 1, wherein the delivery mechanism is configured to deliver a substantially uniform distribution of the first and second laser wavelengths to the skin area to be treated.

3. The device of claim 2, wherein the delivery mechanism includes a light guide having a first end located adjacent to the laser diode bar stack and a second end configured for placement proximate the skin area to be treated.

4. The device of claim 3, wherein a length of the light guide is dimensioned to allowing mixing of the first and second laser wavelengths to achieve the substantial uniform distribution of the first and second laser wavelengths to the skin area to be treated.

5. The device of claim 3, wherein an output window is arranged at the second end of the light guide.

6. The device of claim 1, wherein the first laser wavelength is shorter than 790 nm and the second laser wavelength is longer than 790 nm.

7. The device of claim 1, wherein the first and second laser wavelengths are both longer than 790 nm.

8. The device of claim 1, wherein the first and second laser wavelengths are both shorter than 790 nm.

9. The device of claim 1, wherein the first and second laser wavelengths are both in the range of 600 nm to 1100 nm.

10. The device of claim 1, further comprising an electrical power supply configured to supply electrical power to the laser diode bar stack of the hand piece.

11. The device of claim 10, wherein the electrical power supply is configured to supply pulses of electrical power having a duration in the range of 5 ms to 300 ms.

12. The device of claim 10, wherein the electrical power supply is configured to supply electrical power to the laser diode stack to achieve an applied output of laser energy to the skin area to be treated in the range of 3 J/cm.sup.2 to 100 J/cm.sup.2.

13. The device of claim 1, wherein the handpiece further includes a cooling system configured to cool the skin area to be treated when placed adjacent thereto.

14. A method of using the device of claim 1, the method comprising: placing the hand piece proximate the skin area to be treated; and powering the laser bar stack to apply a mix of the first and second laser wavelengths to the skin area to be treated via the delivery mechanism.

15. The method of claim 14, wherein the method is performed for hair removal from the skin area to be treated.

16. The method of claim 14, wherein the method further comprises cooling the skin area to be treated during at least one of: a period prior to application of the mix of first and second laser wavelengths; a period during application of the mix of first and second laser wavelengths; and a period after application of the mix of first and second laser wavelengths.

17. The method of claim 14, wherein the method further comprises cooling the skin area to be treated during all of: a period prior to application of the mix of first and second laser wavelengths; a period during application of the mix of first and second laser wavelengths; and a period after application of the mix of first and second laser wavelengths.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic view of a laser diode bar stack where laser wavelengths emitted alternate between each adjacent laser diode bar;

(2) FIG. 2 is a schematic view of a laser diode bar stack where two laser diode bars emitting a first laser wavelength alternate with individual laser diode bars emitting a second laser wavelength;

(3) FIG. 3 is a schematic block diagram of a device for hair removal, including a handpiece and support equipment; and

(4) FIG. 4 is schematic view of the handpiece of FIG. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(5) Referring first to FIG. 1, a laser diode bar stack is shown, a first laser wavelength emitted therefrom being represented by dashed arrows and a second laser wavelength emitted therefrom being represented by solid arrows. Coolant flow (e.g., water) enters the laser diode bar stack through a coolant inlet 101 to cool the laser diode bars and then exits through a coolant outlet 102. Pulses of electrical power are applied to the laser diode bar stack through the contacts 103 (anode) and 104 (cathode). The first laser diode bars 105 are configured to emit the first laser wavelength and the second laser diode bars 106 are configured to emit the second laser wavelength.

(6) Referring to FIG. 2, an alternate laser diode bar stack is shown. With dashed and solid arrows representing first and second laser wavelengths emitted therefrom, as in FIG. 1. Also as in FIG. 1, coolant flow enters the laser diode bar stack through a coolant inlet 201, cools the laser diode bars, and exits via a coolant outlet 202, and pulses of electrical power are applied through the contacts 203 (anode) and 204 (cathode). First laser diode bars 205 are configured to emit the first laser wavelength and second laser diode bars 206 are configured to emit the second laser wavelength. As will be appreciated, a single second laser diode bar 206 is placed adjacent each group of two first laser diode bars 205.

(7) Referring to FIG. 3, the laser treatment device includes support equipment 300, which can advantageously be located on a common platform. The support equipment 300 includes a cooling system 301 and an electrical power supply 305. The cooling system 301 includes coolant reservoir 302, a coolant pump 303 for circulating the coolant through the hand piece 306, and a heat exchanger 304 for removing heat from the warmer coolant returning from the hand piece 306.

(8) The power supply 305 generates the pulses of electrical power required by the hand piece 306 to generate the pulses of optical (laser) energy, per whatever treatment parameters are selected via the user interface 307. The user interface 307 and/or support equipment incorporate one or more processors and non-transient memory storage devices to receive treatment parameter settings from users, calculate operational settings based thereon, control the supply of electrical power and/or cooling, and display device and treatment status information to users.

(9) Referring to FIG. 4, the laser diode stack 401 is located in the hand piece 306. A transparent light guide 402 is located in the hand piece 306 in the path of laser light emitted from the stack 401, thereby collecting the optical radiation and delivering it to the skin surface. Thermo-electric cooling elements 403 are attached to a metal sleeve 404 surrounding the light guide 402. The metal sleeve 404 around the light guide 402 allows more effective cooling of light guide and the skin surface placed in contact therewith, enhancing treatment safety. The optical energy (in the form of a plurality of different wavelengths) generated by the laser diode bar stack 401 passes through the light guide 402 and out the output window 408 prior to delivery to the skin surface to be treated. A harness 407 includes electrical wires and coolant tubes for connection with the cooling system 301 and electrical power supply 305 of the support equipment 300 (see also, FIG. 3).

(10) According to a method of treatment: 1. treatment parameter are set including treatment fluence, pulse duration and pulse structure via the user interface; 2. the device calculates the parameters of the electrical power to be supplied, including the electrical current, pulse width and structure, based on the set treatment parameters: 3. the hand piece output window is placed adjacent to the skin area to be treated; and 4. the electrical pulses are generated by the power supply and delivered to the hand piece to generate the multiple laser wavelengths for delivery to the skin area to be treated.

(11) The foregoing description is provided for illustrative and exemplary purposes; the present invention is not necessarily limited thereto. Rather, those skilled in the art will appreciate that various modifications, as well as adaptations to particular circumstances, are possible within the scope of the invention as herein shown and described.