Investigation of Soliton phenomena for laser transfer in optical fibers and its application in tissue treatment

Human skin has three-layer non-homogeneous tissue. The thermal and physical properties of each layer including Epidermis, dermis, and hypodermis are different from each other. In treatment procedures, laser source intensity is adjusted based on thermal amount which produced in each skin layer; furthermore, intensity control, optimization, and prediction of pulse shape before the interaction with tissue, is very important. Since, during the Laser-tissue irradiation, tissue temperature increases, and so uncontrollable temperature enhancement causes thermal harm on tissue.In this research, the Solitons general equation was considered. In order to having a predefined Gaussian shape of output laser pulse at the end of the transfer medium (optical fiber), numerical calculation was used. Solitons coefficients equation, include the dispersive coefficient, propagation constant, and coefficient of normalized loss has been obtained. The results could be used in determination of laser transfer medium structure, such as kind of material, coefficient of refractive, diameter and longitude length and etc. Recognition of fiber medium helps designers to provide a medium in order to establish Soliton, which input pulses are gained as output at the end of the fiber without any changes in shape. Access to different internal human organs could be possible by flexibility of optical fibers, as an important advantage. It seems, optimum parts determination of transfer medium may provide new horizon in controlled laser therapy.