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EXCIMER LASER
ABDUL MOQEET
The Professional Medical Journal , 2008,
Abstract: Objectives: To evaluate the efficacy and safety of excimer laserphotorefractive keratectomy for myopia in Pakistani people. Design: Prospective study. Setting: At Al-Shifa Trust EyeHospital Rawalpindi. Period: October, 1995 and Febrauray, 1996. Material & Methods: The study group of thirteenpatients, comprises of 25 eyes, with refractive error ranging from -1.50 to -3.50 D.S (diopters sphere) and less than-1.50 D.C (diopters cylinder). Results: Thirteen eyes (52%) lost to follow up after three months. Only twelve eyes (48%)could be reviewed at six months after photorefractive keratectomy. At one month, eleven eyes (44%) and at threemonths, eight eyes (32%) were hypermetropic within +0.25 to +1.00 diopters of spherical equivalent .At six months onlythree eyes (25%) had hypermetropia within +0.25 to +1.00 diopters spherical equivalent. None of the eyes had anykind of astigmatism more than 1.00 diopter. No over correction of more than +1.00 diopter of spherical equivalent wasobserved in any case. At one month, three months and six months after photo-refractive keratectomy, 88%, 80% and100% eyes had 6/6 visual acuity respectively, without any optical aid. Hundred percent of the eyes showed completehealing of the epithelium on third post operative day. Moderate to severe postoperative pain was experienced by everyone for three days with gradual reduction in intensity. Only one eye (8.33%) had grade 1 haze at six months. Restsof the eyes were clear .No vision threatening complications occurred. Despite the short term follow up, photorefractivekeratectomy appears to be an effective and safe procedure with good predictability for the correction of low myopia.Conclusion: Despite relatively short term follow up of the study; photo refractive keratectomy (PRK) appears to be safeand quite predictable procedure for correction of low myopia.
Mitomicina C e "Excimer laser"
Wallau, Anelise Dutra;Leoratti, Maria Cristina Ventura;Campos, Mauro;
Arquivos Brasileiros de Oftalmologia , 2005, DOI: 10.1590/S0004-27492005000600031
Abstract: mitomycin c is an antimetabolite agent that blocks dna and rna replication and protein synthesis. it has been used in several ophthalmologic areas, and recently as a modulator of corneal wound healing in excimer laser surgeries. a single application of mitomycin c during surface corneal photoablative surgery seems a safe and efficient therapeutic option for eyes with corneal opacity and/or as prophylaxis in eyes with high risk for corneal opacity development. the use of this drug in photoablative surgery should be cautious until long-term safety results have been reported. the present text presents a review about corneal wound healing with the use of mitomycin c.
Nanomechanical properties of silicon surfaces nanostructured by excimer laser  [cached]
Prashant Kumar and M S R N Kiran
Science and Technology of Advanced Materials , 2010,
Abstract: Excimer laser irradiation at ambient temperature has been employed to produce nanostructured silicon surfaces. Nanoindentation was used to investigate the nanomechanical properties of the deformed surfaces as a function of laser parameters, such as the angle of incidence and number of laser pulses at a fixed laser fluence of 5 J cm 2. A single-crystal silicon [311] surface was severely damaged by laser irradiation and became nanocrystalline with an enhanced porosity. The resulting laser-treated surface consisted of nanometer-sized particles. The pore size was controlled by adjusting the angle of incidence and the number of laser pulses, and varied from nanometers to microns. The extent of nanocrystallinity was large for the surfaces irradiated at a small angle of incidence and by a high number of pulses, as confirmed by x-ray diffraction and Raman spectroscopy. The angle of incidence had a stronger effect on the structure and nanomechanical properties than the number of laser pulses.
Ceramics Surface Modification by Excimer Laser Metal Coating
Weidou ZHU,and Haicheng GU,

材料科学技术学报 , 1994,
Abstract: Thin metallic layers (~ 2 μm) of Ni were deposited on polycrystalline Al2O3. ZrO2 and (Ce-TZP)+Al2O3 ceramic substrates. and further irradiated with pulsed excimer (Xeno chloride) laser pulses. The laser energy density was varied from 0.21 to 0.81 J / cm2 to optimize bending strength. For ZrO2 ceramic, it was found that the strength increases from 530 to 753 MPa at 0.51 J / cm2 irradiation. For Al2O3 and (Ce-TZP)+ Al2O3 the fracture strength also increases in varying degree. The causes of strength increment were discussed.
Excimer laser cleaning of mud stained paper and parchment  [cached]
Duarte, J. P.,Pe?as, P.
Revista de Metalurgia , 1998,
Abstract: The main advantage of excimer lasers when processing materials, its the emission of a radiation with wavelength in the ultraviolet region. This characteristic allows an extremely accurate and very well defined shape of material removal as well as total absence of heat affected zone and alterations in the material structure. In excimer laser paper and parchment cleaning, the mud is removed by breaking the physicalchemical bonding between this last one and the material to be cleaned not affecting neither its structure nor the chromatic pigment existing in some samples. A principal vantagem dos lasers de excímeros, no processamento de materiais, é a emiss o de um feixe luminoso com comprimento de onda compreendido na regi o do ultravioleta, permitindo urna remo ao do material com precis o muito elevada e excelente defini o de bordos, ausência de zona térmicamente afectada e ausência de altera es da estrutura. Na limpeza dos papéis e pergaminhos a lama é removida por quebra das liga es fisico-químicas entre a lama e o papel n o se afectando a estrutura deste, assim como n o se afectaram os pigmentos cromáticos existentes em algumas amostras.
Surface Modification of Ceramic Materials Using Excimer Laser
Yingna WU,Zhongchao FENG,Jing LIANG,

材料科学技术学报 , 2000,
Abstract: Changes of surface morphology following XeCl excimer laser irradiation were investigated for three engineering ceramic materials (Al2O3, Al2O3-SiC nanocomposite and Si3N4) Al2O3 and Al2O3-SiC nanocomposite samples exhibit a smooth rapid melt layer on the surface, and the formation of the metastable gamma-Al2O3 was observed. A silicon-rich layer on the surface was formed after laser irradiation of Si3N4. The toughness K-1c of the materials was measured by the indentation fracture method. After laser irradiation, the toughness of Al2O3, Al2O3-SiC nanocomposite and Si3N4 was improved to various degrees: Al2O3-SiC nanocomposite, 60% (max.), Al2O3, 40% (max.), Si3N4, 12% (max.).
Evolution of Ge and SiGe Quantum Dots under Excimer Laser Annealing
HAN Gen-Quan,ZENG Yu-Gang,YU Jin-Zhong,CHENG Bu-Wen,YANG Hai-Tao,
韩根全
,曾玉刚,余金中,成步文,杨海涛

中国物理快报 , 2008,
Abstract: We present different relaxation mechanisms of Ge and SiGe quantum dotsunder excimer laser annealing. Investigation of the coarsening and relaxation of the dots shows that the strain in Ge dots on Ge films is relaxed by dislocation since there is no interface between the Ge dots and the Ge layer, while the SiGe dots on Si0.77Ge0.23 film relax by lattice distortion to coherent dots, which results from the obvious interface between the SiGe dots and theSi0.77Ge0.23 film. The results are suggested and sustained by Vanderbilt and Wickham's theory, and also demonstrate that no bulk diffusion occurs during the excimer laser annealing.
Does Pimecrolimus Cream Enhance the Effect of Excimer Laser on Eyelid Vitiligo?
Behrooz Barikbin,Golsan Kardan,Maryam Yousefi,Hamideh Moravvej
Journal of Lasers in Medical Sciences , 2011,
Abstract: INTRODUCTION: Vitiligo is a cutaneous disorder of pigmentation, for which, there are some proven modalities of treatment. In this study, we evaluated the efficacy of the addition of topical pimecrolimus to 308nm Excimer laser in reducing treatment duration and improving the response rate of eyelid vitiligo, compared with 308nm Excimer laser monotherapy. METHODS: Fifty two symmetrically localized lesions of eyelid vitiligo in 26 patients were observed. Each of vitiliginous patches was treated with 308nm Excimer laser twice a week for a total of 30 sessions. Topical pimecrolimus 1% cream was applied to the patches of right eyelid(group A lesions) and eucerine cream as a placebo to the left side patches(group B lesions)twice daily, throughout the study. Photographs were taken at baseline, 6 and 15 weeks after starting the treatment. RESULTS: Twenty two patients (44 lesions) completed the study. Repigmentation was appeared in all (100%) of groups A and B lesions. A 75% or more repigmentation was achieved in 17(78%) of group A versus 14 (64%) of group B lesions. The average number of sessions needed for the appearance of repigmentation was 8 for group A lesions and 12 for group. The repigmentaion of 50% or more in patients with disease duration of 2 years or less and those with more than 2 years duration ere 100% and 59.2%, respectively. CONCLUSION: Repigmentation rate obtained by the combination therapy of eyelid vitiligo with 308nm Excimer laser and topical Pimecrolimus 1%cream is significantly higher, and obtained in fewer sessions in comparison with 308nm Excimer laser and placebo combination therapy.
On-Line Estimation of Laser-Drilled Hole Depth Using a Machine Vision Method  [PDF]
Chao-Ching Ho,Jun-Jia He,Te-Ying Liao
Sensors , 2012, DOI: 10.3390/s120810148
Abstract: The paper presents a novel method for monitoring and estimating the depth of a laser-drilled hole using machine vision. Through on-line image acquisition and analysis in laser machining processes, we could simultaneously obtain correlations between the machining processes and analyzed images. Based on the machine vision method, the depths of laser-machined holes could be estimated in real time. Therefore, a low cost on-line inspection system is developed to increase productivity. All of the processing work was performed in air under standard atmospheric conditions and gas assist was used. A correlation between the cumulative size of the laser-induced plasma region and the depth of the hole is presented. The result indicates that the estimated depths of the laser-drilled holes were a linear function of the cumulative plasma size, with a high degree of confidence. This research provides a novel machine vision-based method for estimating the depths of laser-drilled holes in real time.
Excimer” laser 308nm no tratamento do vitiligo
Tania Nely Rocha,Rafael Henrique Rocha
Surgical & Cosmetic Dermatology , 2010,
Abstract: Introdu o: O vitiligo é doen a idiopática adquirida, caracterizada por manchas hipocr micas e acr micas bem delimitadas, sendo o Excimer Laser 308nm um dos possíveistratamentos para essa dermatose. Objetivo: Analisar estudos publicados em revistas indexadas sobre a utiliza o do Excimer Laser 308nm, no tratamento de vitiligo. Método: Pela abordagem qualitativa, fez-se levantamento bibliográfico de artigos científicos relacionados ao tema no período de 2001 a 2009, nas bases de dados Medline, Lilacs e Scielo. Resultados: Segundo essa revis o bibliográfica o Excimer Laser 308nm apresentou resultados positivos no tratamento de vitiligo.As les es recentes e as localizadas na face respondem melhor do que as de outros locais. As extremidades s o de resposta mais difícil. A idade do paciente n o interfere no resultado. Em média, foram necessárias 11 sess es até o início da repigmenta o.O ideal é que a aplica o seja feita uma a três vezes por semana, com intervalo nunca inferior a 48 horas. Conclus o: O Excimer Laser no tratamento de vitiligo é efetivo e seguro quando comparado a outras modalidades de tratamento. O resultado depende da localiza o e do tempo da doen a.
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