Laser system and method for treatment of biologic targets
View Patent ↗A long pulse alexandrite laser for treating dermatological specimens is disclosed. The use of alexandrite allows operation in the near-infrared, specifically in a 50 nm range surrounding 755. Infrared in this range allows good penetration while still achieving an acceptable ratio of hemoglobin to melanin absorption In addition, a method and related system for treating biologic tissue with pulse light includes generating a long effective output light pulse comprising a series of sub-pulses having a fractional duty cycle over a selected effective pulse duration, a periodicity that is less than the thermal relaxation time of a targeted structure, and an interpulse-delay between successive sub-pulses that is greater than the thermal relaxation time of non-targeted structures within the treatment area; and delivering the output light to the tissue of a patient.
1. A method for wearing biologic tissue with pulse light, comprising:
generating a long effective output light pulse comprising a series of sub-pulses having a fractional duty cycle over a selected effective pulse duration, a periodicity that is less than the thermal relaxation time of a targeted structure, and an interpulse-delay between successive sub-pulses that is greater than the thermal relaxation time of non-targeted structures within the treatment area, the targeted structures being substantially adjacent to the non-targeted structures within the treatment area; and
delivering the output light to the tissue of a patient.
2. The method as described in claim 1 wherein the output light pulse comprises a laser light pulse.
3. The method as described in claim 1 wherein the effective pulse duration is approximately equal to the thermal relaxation time of the targeted structure.
4. The method as described in claim 1 wherein the targeted structure comprises blood vessels.
5. The method as described in claim 4 wherein the targeted blood vessels are larger than 30 microns in diameter.
6. The method as described in claim 1 wherein the effective pulse duration is larger than 0.1 msec.
7. The method as described in claim 1 wherein the effective pulse duration is larger than 0.5 msec.
8. The method as described in claim 1 wherein the effective pulse duration is larger than 5 msec.
9. The method as described in claim 1 wherein the effective pulse duration is larger than 50 msec.
10. The method as described in claim 1 wherein the non-targeted structures include nonnal-sized blood-vessels.