The use of titanium and its alloys has increased in various industries recently, because of their superior properties of these alloys. Titanium alloys are generally classified as difficult to machine materials because of their thermo-mechanical properties such as high strength-to-weight ratio and low thermal conductivity. Laser Assisted Machining (LAM) improves the machinability of high strengt...

introduction: the aim of this study was to investigate the scanning electron microscope (sem) analysis of tooth surface irradiated by different parameters of er:yag laser. methods: 15 caries-free extracted human third molars were used in this study. the teeth were put into 5 groups for laser irradiation as follows: group 1 (power: 2.5 w, energy: 250 mj); group 2(power: 3 w, energy: 300 mj); gro...

radiotherapy in the head and neck region and chemotherapy might give rise to oral mucositis which is a severe and painful inflammation. there is no known definite cure for mucositis. a number of studies have attempted to evaluate the effect of low-power laser on radiotherapy- and chemotherapy-induced mucositis. the present study was undertaken to evaluate the effect of low-power laser on the pr...

The modulation instability (MI) is one of the main factors responsible for the degradation of beam quality in high-power laser systems. The so-called B-integral restriction is commonly used as the criteria for MI control in passive optics devices. For amplifiers the adiabatic model, assuming locally the Bespalov-Talanov expression for MI growth, is commonly used to estimate the destructive impa...

Hybrid femtosecond lasers combine the chirped pulse amplification (CPA) in laser media with optical parametric chirped pulsed amplification (OPCPA) in nonlinear crystals. A key feature of these systems consists in matching the parametric amplification gain bandwidth of nonlinear crystals to the spectral gain bandwidth of laser amplifying crystals. Gain bandwidths as broad as 150 nm can be obtai...

A theoretical model for laser cooled continuous-wave fiber amplifier is presented. The amplification process takes place in the Tm 3+ -doped core of the fluoride ZBLAN (ZrF4-BaF2LaF3-AlF3-NaF) glass fiber. The cooling process takes place in the Yb 3+ :ZBLAN fiber cladding. It is shown that for each value of the pump power and the amplified signal there is a distribution of the concentration of ...