A welding seam tracking visual sensor based on laser scanning is designed to solve the problems, such as indistinct image, difficulty in processing image etc., caused by serious arc light interference during welding. This visual sensor is mainly composed of a scanning motor, a linear-array CCD, a scanning rotating mirror and a semiconductor laser. Because the sensor measurement precision relies...

objective: the aim of this study was to evaluate and compare the effect of dental surface treatment with er:yag , nd:yag ,co2 lasers and sodium ascorbate to recently laser bleached enamel by scanning electron microscope (sem). methods: 15caries-free extracted human third molars were selected for this study. the samples were bleached by heydent jw power activated by diode laser 810 nm. after 7 d...

in this paper, the output power behavior of the wave-guide cw-co2 laser versus efficient parameters of laser performance was investigated. the output power variation versus the discharge current, the pressure and the gas mixture ratio was studied and optimized. the maximum output powers of 6 and 14.5 w were respectively obtained at operating pressures 78 and 50 mbar in two tubes of 3 mm same di...

a 47 year-old woman presented with eight-month history of tattoo allergic reaction of eyebrows after botulinum toxin a injection that was resistant to oral, topical and intralesional injection of corticosteroids. multiple sessions of treatment with co2 fractional laser resulted in significant flattening of allergic papules and plaques as well as reduction of tattoo pigmentation

introduction: definitive treatment of oral leukoplakia is very important because of its recurrences and malignant transformation depending on the location, clinical feature,degree of dysplasia and etiological factors. there are different kinds of treatment for this lesion, but using high power laser has some advantages like less pain, swelling, prevention of metastasis, edema, less bleeding (dr...

Background. Laser welding was first reported in 1967 and for many years it has been used in dental laboratories with several advantages versus the conventional technique. Authors described, in previous works, the possibility of using also chair-side Nd : YAG laser device (Fotona Fidelis III, λ = 1064 nm) for welding metallic parts of prosthetic appliances directly in the dental office, extra- a...

In this study, a three-dimensional (3D)finite elementmodel is developed to investigate thermally induced stress field during hybrid laser–gas tungsten arc welding (GTAW) process. In the hybridwelding case, we focus on the GTAWprocess sharing commonmolten poolwith laser beam and playing an augment role in thehybridweldingsystem.Anexperiment-based thermalanalysis isperformedtoobtain the temperatu...

Welding-induced distortion is an intrinsic problem arising due to the mismatch of thermal expansions in the weld and surrounding material. The distortion can be minimized through the pre-process, in process, or post-process methodology. In the present paper, the laser forming (LF) technology is utilized for the post correction of the welding-induced distortion. Three types of weld paths are app...

The Nd:YAG laser welding was used to join the binary NiTi alloy wires with different compositions(Ti–50.0 at.%Ni and Ti–50.9 at.%Ni) which had the same diameter of 1 mm. The wires were welded with different parameters, including impulse width and welding current. The aim was to assess the influence of the laser-welding process on the microstructure and mechanical properties of the welded joint ...

rhinophyma is a severe late complication of rosacea, which is characterized by progressive hyperplasia of sebaceous glands and connective tissue involving the lower two-thirds of the nose. it can be an emotionally devastating disorder, and serve as a medium for occult cancers and other health problems. many surgical treatments have been advocated, as well as dermabrasion and laser therapy. in l...