In this paper propagation of combined laser beam through atmosphere is investigated. Laser beam is combined via lens array arrangement. Turbulence is considered as an affecting factor of atmosphere and its effects on transverse coherence length (Fried parameter), peak intensity, propagation efficiency, and spot size of the laser beam is investigated. Coherent and incoherent combined beam are co...

Background: Acupuncture is an indispensable part of traditional Chinese medicine for relief of pain. The purpose of this study was the immediate & latent of low power LASER Ga-Al-As irradiation applied to acupuncture points on experimental pain threshold. Methods: This quasi-experimental study was conducted on seventy adult women ranging from 20 to 40 years old assigned randomly into two groups...

   Self-heating leads to a temperature rise of the laser diode and limits the output power and efficiency due to increased loss and decreased differential gain. To control device self-heating, it is required to design the laser structure with a low optical loss, while the heat flux must spread out of the device efficiently. In this study, a new asymmetric waveguide design is proposed and th...

Introduction: The aim of the present study was to determine burn intensity in retinal laser photocoagulation based on laser parameters; wavelength, power, beam size and pulse duration, using Optical Coherence Tomography (OCT), fundus camera, physical eye model and computer simulation in a clinical study.Materials and Methods: Participants were 10 adult patients between 50-80 years with prolifer...

Background: There is a large variety of therapeutic agents for the treatment of vitiligo, but it still remains a challenge. Narrow-band UVB phototherapy and 308-nm excimer laser have been shown to be safe and effective for the treatment of vitiligo. Topical calcipotriol has recently been reported to enhance the efficacy of phototherapy, especially 8-methoxypsoralen plus UVA (PUVA). The goal of ...

In a ring laser gyroscope, due to the rotation and the Sagnac effect, a phase difference between the two counter-propagating beams is generated. In this device, the higher phase difference between these two beams causes the better the interference pattern detection, and thus the sensitivity is increased. In this paper, the effect of inserting a dielectric-graphene photonic crystal inside a ring...

A quantum theory of a two and three-level laser with injected atomic coherence is developed by using a density operator method, to the best of our knowledge, for the first time. The initial atomic coherence plays an essential role. At steady state, the equation of motion for the density operator yields to exhibit laser without inversion and a phase locking but no threshold for the laser fie...