Laser System For Skin Treatment
A method of treating pigmented lesions and vascular lesions by a wavelength between 500 nm and 600 nm applied to the segment of skin as a train of pulses. In some examples, a wavelength of 1048 nm is applied sequentially or simultaneously with the wavelength between 500 nm and 600 nm. Disclosed is also an apparatus supporting such skin treatment.
1 . A method of skin treatment comprising:
applying to a segment of skin with pigmented lesions and vascular lesions a laser light with a wavelength between 500 nm and 600 nm;
delivering the laser light to the segment of skin with pigmented lesions and vascular lesions in a train of sub-pulses filing-in each macro pulse in a sequence of laser light macro pulses, wherein duration of the sub-pulses is in a range of 5 ns to 200 ns, and duration of the macro pulses is in a range 0.1 ms to 100 ms.
2 . The method according to claim 1 wherein delivering the laser light to the segment of skin in a train of sub-pulses with wavelength of 524 nm.
3 . The method according to claim 1 wherein delivering the laser light to the segment of skin in a train of sub-pulses with wavelength of 532 nm.
4 . The method according to claim 1 wherein delivering the laser light to the segment of skin in a train of sub-pulses including a combination of two wavelengths of 524 nm and 1048 nm.
5 . The method according to claim 1 , wherein the sub-pulses have a repetition rate of 10 kHz-1 MHz.
6 . The method according to claim 1 , wherein envelope of a sequence of macro pulses of laser light has a repetition rate of 1 Hz to 10 Hz.
7 . The method according to claim 1 , wherein each macro pulse contains at least 20 micropulses.
8 . The method according to claim 1 further comprising using a combination of 1064 nm and 532 nm wavelengths for treating pigmented lesions, vascular lesions, and for skin toning, and delivering each of the wavelengths as a pulse train.
9 . The method according to claim 8 wherein the pulse train is defined as each sub-pulse having a duration of 5 ns to 200 ns, and the duration of a macro pulse being 0.1 ms to 100 ms.
10 . The method according to claim 1 further comprising delivering a combination of 1064 nm and 532 nm wavelengths for treating pigmented lesions, vascular lesions, and for skin toning , as a pulse train, the pulse train defined as each sub-pulse having a duration of 5 ns to 200 ns, a total duration of the pulse train being 0.1 ms to 100 ms.
11 . A method according to claim 1 further comprising using an alexandrite laser to pump a neodymium doped laser medium to produce the laser light.
12 . The method according to claim 11 wherein the alexandrite laser is a laser configured to treat other dermatologic conditions.
13 . The method according to claim 1 wherein delivering the laser light to the segment of skin as a combination of two wavelengths of 524 nm 1048 nm and wherein fluence ratio of the 524 nm wavelength to the 1048 nm wavelength is 1:3 to 1:10.
14 . An apparatus to generate a train of sub-pulses comprising:
a flash-lamp pumped free-running alexandrite laser configured to generate a sequence of laser light macro pulses with each macro pulse having a duration of 0.1 to 100 msec;
an Neodymium doped laser medium pumped by the free running alexandrite laser;
a passive Q-switch configured to generate a train of laser light sub-pulses within an envelope of 0.1 ms to 100 ms;
a beam shaping optical system; and
a second harmonic generator and a lens to focus laser light generated by the neodymium doped laser medium into a fiber for delivery to a segment of skin.
15 . The apparatus according to claim 14 wherein the neodymium-doped laser medium is a Nd:YLF rod.
16 . The apparatus according to claim 14 wherein the passive Q-switch is a Cr 4+ :YAG crystal.
17 . The apparatus according to claim 14 wherein the second harmonic generator is a Lithium Triborate (LiB 3 O 5 or LBO) nonlinear optical crystal.
18 . The apparatus according to claim 13 wherein the second harmonic generator is a non-critically phase matched Lithium Triborate (LiB 3 O 5 or LBO) nonlinear optical crystal.
19 . The apparatus according to claim 14 wherein the second harmonic generator produces a laser light with wavelength of 524 nm.
20 . The apparatus according to claim 19 wherein the second harmonic generator produces a laser light with wavelength of 524 nm and wherein the wavelength of 524 nm matches absorption coefficient of blood (mixture of oxy and deoxyhemoglobin) and pigment (melanosomes).
21 . The apparatus according to claim 14 wherein a train of laser light sub-pulses directed to a segment of skin comprises laser light with a combination of two wavelengths of 524 nm 1048 nm.
22 . The apparatus according to claim 20 wherein a fluence ratio of a 524 nm wavelength to a wavelength of 1048 nm is 1 to 3 to 1 to 10.
23 . The apparatus according to claim 14 wherein delivered laser light fluence of a train of laser sub-pulses at the segment of skin is 3 J/cm 2 -30 J/cm 2 .
24 . The apparatus according to claim 14 wherein each macro pulse contains at least 20 micro pulses.
25 . A method comprising:
providing a combined laser light with wavelength between 500 nm and 600 nm and wavelength of 1048 nm;
generating from the combined laser light a sequence of macro pulses with each macro pulse filled-in by a train of sub-pulses;
applying the combined laser light with a sequence of macro pulses filled-in by a train of sub-pulses to a segment of skin with pigmented lesions and vascular lesions and removing the lesions.