M. Calin, M. Tomescu, R. Rădvan, M. Radu, T. Necsoiu
The medical laser applications use the thermal effects of laser irradiation. The present work contains applications of the thermovision. This method offers the following advantages recording and processing of the thermal distribution on the irradiated zone. The study has in view the development of an algorithm of work for an useful data base regarding the laser application in medicine. The experiments used Ar laser, laser diode and some kinds of biological tissues. The paper presents some thermal distributions before, during and after laser irradiation and the images processing.
{"title":"Comparative study of the thermal effects generated by laser irradiation for medical applications","authors":"M. Calin, M. Tomescu, R. Rădvan, M. Radu, T. Necsoiu","doi":"10.1117/12.312655","DOIUrl":"https://doi.org/10.1117/12.312655","url":null,"abstract":"The medical laser applications use the thermal effects of laser irradiation. The present work contains applications of the thermovision. This method offers the following advantages recording and processing of the thermal distribution on the irradiated zone. The study has in view the development of an algorithm of work for an useful data base regarding the laser application in medicine. The experiments used Ar laser, laser diode and some kinds of biological tissues. The paper presents some thermal distributions before, during and after laser irradiation and the images processing.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131993997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Radu, D. Ciotaru, M. Calin, G. Savi, M. Bota, C. Stroilă
In vitro (absorption spectroscopy) and in vivo (fluorescence microscopy) studies before and after the uptake of intraperitoneal injected Hematoporphyrin Derivative (HpD) were made in mice. The absorption spectrum of HpD is characterized by four bands in the visible region with decreasing absorption towards longer wavelengths (510 nm, 540 nm, 568 nm and 621 nm). These spectra were obtained only at low concentration (10-5 M). After (15 - 30) minutes postirradiation (He-Ne laser, 1 mW) the features of curves were the same with those of nonirradiated samples but with a deplacement of wavelengths. The presence of laser emitting products was pointed out by fluorescence microscopy (cryostat section in fluorescence microscopy).
{"title":"Photodynamic therapy using hematoporphyrin derivative and He-Ne laser irradiation in Erlich tumor: an experimental study on mice","authors":"M. Radu, D. Ciotaru, M. Calin, G. Savi, M. Bota, C. Stroilă","doi":"10.1117/12.312654","DOIUrl":"https://doi.org/10.1117/12.312654","url":null,"abstract":"In vitro (absorption spectroscopy) and in vivo (fluorescence microscopy) studies before and after the uptake of intraperitoneal injected Hematoporphyrin Derivative (HpD) were made in mice. The absorption spectrum of HpD is characterized by four bands in the visible region with decreasing absorption towards longer wavelengths (510 nm, 540 nm, 568 nm and 621 nm). These spectra were obtained only at low concentration (10-5 M). After (15 - 30) minutes postirradiation (He-Ne laser, 1 mW) the features of curves were the same with those of nonirradiated samples but with a deplacement of wavelengths. The presence of laser emitting products was pointed out by fluorescence microscopy (cryostat section in fluorescence microscopy).","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"518 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133791919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this study is to present the results of the application of remote sensing techniques for seismic risk analysis, which estimates the geographic distribution, frequency, and intensity of seismic activity, without attempting to predict specific events. This method is based on the recognition of the active faults, which are defined as breaks along which movement has occurred in Holocene time (past 11,000 years). Remote sensing analysis and field studies of active faults can provide a geologic history that overcomes many of the shortcomings of instrumental and historic records.
{"title":"Satellite remote sensing data applied for seismic risk assessment of the Vrancea region","authors":"M. Zoran, C. L. Braescu, C. Aiftimiei","doi":"10.1117/12.312662","DOIUrl":"https://doi.org/10.1117/12.312662","url":null,"abstract":"The aim of this study is to present the results of the application of remote sensing techniques for seismic risk analysis, which estimates the geographic distribution, frequency, and intensity of seismic activity, without attempting to predict specific events. This method is based on the recognition of the active faults, which are defined as breaks along which movement has occurred in Holocene time (past 11,000 years). Remote sensing analysis and field studies of active faults can provide a geologic history that overcomes many of the shortcomings of instrumental and historic records.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123020704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A mode of quantic detection for noncoherent optical radiation as noise limit is presented. Using the representation on coherent state of density matrix operators ((rho) ) and of detection operators ((pi) ), the detection probability (Qd), false alarm probability (Qo) and signal-noise ratio (S/Z), are estimated, as function of the number of freedom degrees of temporal oscillation modes (Mt) and of the spatial oscillation modes (Ms). A validation algorithm of statistical hypotheses, resulted from noncoherent optical field analysis, is made using Newman-Pearson criterion.
{"title":"Verifying model for statistical hypothesis in detection of noncoherent radiation","authors":"V. Babin, S. Ersen, A. Moldovan, N. Iftimia","doi":"10.1117/12.312677","DOIUrl":"https://doi.org/10.1117/12.312677","url":null,"abstract":"A mode of quantic detection for noncoherent optical radiation as noise limit is presented. Using the representation on coherent state of density matrix operators ((rho) ) and of detection operators ((pi) ), the detection probability (Qd), false alarm probability (Qo) and signal-noise ratio (S/Z), are estimated, as function of the number of freedom degrees of temporal oscillation modes (Mt) and of the spatial oscillation modes (Ms). A validation algorithm of statistical hypotheses, resulted from noncoherent optical field analysis, is made using Newman-Pearson criterion.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122163850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The selection of the best laser for a given application is a common problem of laser users. However, a direct relationship between laser intrinsic characteristics and a potential application, risks to make the laser source selection process unilateral and partially mistaken. In fact, the best processing technology for a given application must be chosen. Therefore, the present paper proposes an indirect, more realistic selection process. This process starts from a general laser application definition. Then, it passes through the analysis of the needed laser beam--workpiece material interaction and of the necessary laser technological system. Finally, the selection process ends with the laser processing technology definition, where the choice of the most suitable laser source becomes in fact possible.
{"title":"Lasers for material processing","authors":"A. Nichici, I. David, E. Cicala","doi":"10.1117/12.312759","DOIUrl":"https://doi.org/10.1117/12.312759","url":null,"abstract":"The selection of the best laser for a given application is a common problem of laser users. However, a direct relationship between laser intrinsic characteristics and a potential application, risks to make the laser source selection process unilateral and partially mistaken. In fact, the best processing technology for a given application must be chosen. Therefore, the present paper proposes an indirect, more realistic selection process. This process starts from a general laser application definition. Then, it passes through the analysis of the needed laser beam--workpiece material interaction and of the necessary laser technological system. Finally, the selection process ends with the laser processing technology definition, where the choice of the most suitable laser source becomes in fact possible.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125497048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In a unitary approach generally used in quantum optics, we consider Lindblad's Markovian master equation and the non- Markovian master equation of Ford, Lewis and O'Connell. We show that the second-order master equation in the hierarchy obtained from a Krylov-Bogoliubov expansion corresponds to the Born approximation. By time averaging, and neglecting the rapidly varying terms, Lindblad's master equation is obtained. With these two equations, we calculate the decay spectrum. We find that for rather low dissipated energies, only the non-Markovian master equation provides correct results. Based on the independent oscillator model of the dissipative coupling, explicit expressions of the dissipative coefficients are obtained.
{"title":"Non-Markovian effects in dissipative systems","authors":"E. Stefanescu, P. Sterian","doi":"10.1117/12.312679","DOIUrl":"https://doi.org/10.1117/12.312679","url":null,"abstract":"In a unitary approach generally used in quantum optics, we consider Lindblad's Markovian master equation and the non- Markovian master equation of Ford, Lewis and O'Connell. We show that the second-order master equation in the hierarchy obtained from a Krylov-Bogoliubov expansion corresponds to the Born approximation. By time averaging, and neglecting the rapidly varying terms, Lindblad's master equation is obtained. With these two equations, we calculate the decay spectrum. We find that for rather low dissipated energies, only the non-Markovian master equation provides correct results. Based on the independent oscillator model of the dissipative coupling, explicit expressions of the dissipative coefficients are obtained.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132940713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The interaction of radiation with vitreous materials provokes irreversible and reversible changes of atomic and electronic structures. These changes in their turn manifest themselves in the experiment through changes of mechanical, thermal, optical, photoelectrical and other characteristics. Under the radiation influence the structure of vitreous materials changes, new defects appears, film crystallization or amorphization takes place, phase transition or transition from one unstable state to another. It is evident that such changes radically influence the optical and photoelectrical properties of the material: the refraction index and other optical material constants change; reflection and absorption of light as well as photoelectric parameters. Of no less importance is the appearance of new possibilities for application of vitreous materials as optical and photoelectrical recording media, fibers and planar waveguides, active and passive elements of optoelectronics, including nonlinear elements and sensors of different physical quantities. This paper covers a survey of works dedicated to the research of various photoinduced phenomena in bulk, thin-film and fiber samples of chalcogenide glassy semiconductors.
{"title":"Photoinduced phenomena in chalcogenide glasses and their application in optoelectronics","authors":"A. Andriesh","doi":"10.1117/12.312779","DOIUrl":"https://doi.org/10.1117/12.312779","url":null,"abstract":"The interaction of radiation with vitreous materials provokes irreversible and reversible changes of atomic and electronic structures. These changes in their turn manifest themselves in the experiment through changes of mechanical, thermal, optical, photoelectrical and other characteristics. Under the radiation influence the structure of vitreous materials changes, new defects appears, film crystallization or amorphization takes place, phase transition or transition from one unstable state to another. It is evident that such changes radically influence the optical and photoelectrical properties of the material: the refraction index and other optical material constants change; reflection and absorption of light as well as photoelectric parameters. Of no less importance is the appearance of new possibilities for application of vitreous materials as optical and photoelectrical recording media, fibers and planar waveguides, active and passive elements of optoelectronics, including nonlinear elements and sensors of different physical quantities. This paper covers a survey of works dedicated to the research of various photoinduced phenomena in bulk, thin-film and fiber samples of chalcogenide glassy semiconductors.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"417 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117322391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
From the phenomenological point of view, laser cutting processes are complex, weakly organized and diffuse systems. Off line optimization of such processes demands relative simple, but accurate enough models, which could be obtained by experimental way. The article presents the results of a large factorial designed experiment, having three main objectives: to identify which factors are statistically important, to build a quantitative model relating the important factors to the response functions, to optimize these response functions and particularly the material removal rate, the kerf walls parallelism deviation and the specific energy consumption. The obtained results allow the choice of laser cutting optimal parameters.
{"title":"Off-line multiresponse optimization of gas-jet-assisted CO2 laser cutting of polymettacrylate","authors":"E. Cicala, Delia Zsivanov, A. Nichici","doi":"10.1117/12.312769","DOIUrl":"https://doi.org/10.1117/12.312769","url":null,"abstract":"From the phenomenological point of view, laser cutting processes are complex, weakly organized and diffuse systems. Off line optimization of such processes demands relative simple, but accurate enough models, which could be obtained by experimental way. The article presents the results of a large factorial designed experiment, having three main objectives: to identify which factors are statistically important, to build a quantitative model relating the important factors to the response functions, to optimize these response functions and particularly the material removal rate, the kerf walls parallelism deviation and the specific energy consumption. The obtained results allow the choice of laser cutting optimal parameters.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115193669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Excimer lasers are an excellent instrument for performing photorefractive keratotomy, PRK. The UV light from the laser causes an ablation of the cornea in proportion to the intensity of the light. The primary characteristic essential to successful PRK is the uniformity of the Top Hat, or working portion of the laser beam. In order for this intensity profile to be sufficiently uniform for PRK, it is essential to periodically measure the equality of the laser beam profile. This ensures that the laser continues to operate properly and provide the expected performance.
{"title":"Electronic-beam analysis of excimer lasers used for photorefractive keratotomy","authors":"C. Roundy","doi":"10.1117/12.312826","DOIUrl":"https://doi.org/10.1117/12.312826","url":null,"abstract":"Excimer lasers are an excellent instrument for performing photorefractive keratotomy, PRK. The UV light from the laser causes an ablation of the cornea in proportion to the intensity of the light. The primary characteristic essential to successful PRK is the uniformity of the Top Hat, or working portion of the laser beam. In order for this intensity profile to be sufficiently uniform for PRK, it is essential to periodically measure the equality of the laser beam profile. This ensures that the laser continues to operate properly and provide the expected performance.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121197997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this communication we present the results of computational modeling of molecular units as AsmSn registered by mass spectrometry in the As2S3:Snx glasses before and after laser illumination. Using HyperChem Computational Chemistry program we obtained 3D structures, with global minimum energy conformation for following molecules: As4 (3.47); S8 (4.44); As4S3 (11.87); As2S5 (14.36); As2S4 (17.62); As2S6 (19.11); As4S4 (21.88); As4S5 (24.98); As2S3 (25.81); As4S6 (43.13). The model of the As2S3:Sn0.1 glasses, using 200 As atoms, 300 S atoms and 10 Sn atoms for computational modeling, is presented too. Such model shows that a tin atom may be bonded in two ways: when the tin atoms are common for two rings with 12 atoms and when the tin atom are bonded between the layer of the glassy network. When the tin atom are insert in the network rings for 12 atoms the structural model shows the more compact packing of the atoms.
{"title":"Modeling of chalcogenide glass structures before and after laser illumination, based on mass spectroscopy data","authors":"A. Andriesh, A. Buzdugan, V. Dolghier, M. Iovu","doi":"10.1117/12.312761","DOIUrl":"https://doi.org/10.1117/12.312761","url":null,"abstract":"In this communication we present the results of computational modeling of molecular units as AsmSn registered by mass spectrometry in the As2S3:Snx glasses before and after laser illumination. Using HyperChem Computational Chemistry program we obtained 3D structures, with global minimum energy conformation for following molecules: As4 (3.47); S8 (4.44); As4S3 (11.87); As2S5 (14.36); As2S4 (17.62); As2S6 (19.11); As4S4 (21.88); As4S5 (24.98); As2S3 (25.81); As4S6 (43.13). The model of the As2S3:Sn0.1 glasses, using 200 As atoms, 300 S atoms and 10 Sn atoms for computational modeling, is presented too. Such model shows that a tin atom may be bonded in two ways: when the tin atoms are common for two rings with 12 atoms and when the tin atom are bonded between the layer of the glassy network. When the tin atom are insert in the network rings for 12 atoms the structural model shows the more compact packing of the atoms.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123449276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}