M. Kennedy, D. Ristau, G. Dumitru, D. Sporea, Clementina A. Timus
The paper presents the theoretical background of laser calorimetry as a method to investigate the absorptance of optical components, according to the recently adopted ISO Standard 11 551. An experimental set-up for optical absorption measurements, including a cw CO2 laser and a calorimetric chamber, is presented. The calibration of the laser calorimetric set-up is also described. The calibration involved several steps: laser power calibration, evaluation of chamber sensitivity, electrical calibration using electrically heated samples and optical calibration utilizing 100% absorptance samples. There were measured the conversion factors for the laser power and for the sample temperature; there were calculated over-all correction factors for the different substrates and they could be placed within +/- 4% around their mean value.
{"title":"Calibration procedures for a 10.6-μm laser calorimeter","authors":"M. Kennedy, D. Ristau, G. Dumitru, D. Sporea, Clementina A. Timus","doi":"10.1117/12.312718","DOIUrl":"https://doi.org/10.1117/12.312718","url":null,"abstract":"The paper presents the theoretical background of laser calorimetry as a method to investigate the absorptance of optical components, according to the recently adopted ISO Standard 11 551. An experimental set-up for optical absorption measurements, including a cw CO2 laser and a calorimetric chamber, is presented. The calibration of the laser calorimetric set-up is also described. The calibration involved several steps: laser power calibration, evaluation of chamber sensitivity, electrical calibration using electrically heated samples and optical calibration utilizing 100% absorptance samples. There were measured the conversion factors for the laser power and for the sample temperature; there were calculated over-all correction factors for the different substrates and they could be placed within +/- 4% around their mean value.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"114 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":"117205871","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}
I. Baltog, M. Ciurea, G. Pavelescu, E. Pentia, G. Galeata, J. Roger
The influence of the thermal annealing on the optical properties of the porous silicon films was revealed by photoluminescence (PL) and spectroellipsometric measurements. As result of 200 degree(s)C annealing small changes of the dielectric functions could be understood by desorption process of some molecules from Si skeleton surface. Strong changes of PL and dielectric function spectra after the thermal annealing at high temperatures (up to 800 degree(s)C) were explained by the change of the passivation from hydrogen to oxygen and then the beginning of the oxidation process. This oxidation process produces the disappearance of the PL slow component, an important enhancement of PL (2-3 orders of magnitude) and a shift of maximum position to higher energies, corresponding to the thinning of the nanocrystallites from the Si skeleton.
{"title":"Influence of thermal annealing on optical properties of porous silicon films","authors":"I. Baltog, M. Ciurea, G. Pavelescu, E. Pentia, G. Galeata, J. Roger","doi":"10.1117/12.312752","DOIUrl":"https://doi.org/10.1117/12.312752","url":null,"abstract":"The influence of the thermal annealing on the optical properties of the porous silicon films was revealed by photoluminescence (PL) and spectroellipsometric measurements. As result of 200 degree(s)C annealing small changes of the dielectric functions could be understood by desorption process of some molecules from Si skeleton surface. Strong changes of PL and dielectric function spectra after the thermal annealing at high temperatures (up to 800 degree(s)C) were explained by the change of the passivation from hydrogen to oxygen and then the beginning of the oxidation process. This oxidation process produces the disappearance of the PL slow component, an important enhancement of PL (2-3 orders of magnitude) and a shift of maximum position to higher energies, corresponding to the thinning of the nanocrystallites from the Si skeleton.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"21 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":"122912059","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 mathematical model, based exclusively on spectroscopic data concerning radiative, non-radiative, and energy transfer processes, is proposed and used to simulate the Q-switch regime of three-micron Er:YAG laser. The connection between the main energy transfer mechanisms that make possible generation on the self-saturated transition 4I11/2 yields 4I13/2 (up- conversion from 4I13/2 and 4I11/2, cross- relaxation from 4S3/2) and the giant pulse characteristics is discussed. The radiative as well as non- radiative losses during optical pumping and giant pulse generation are defined and evaluated. A particular attention is given to FTIR Q-switch which demonstrated real qualities for 3- micrometers Erbium lasers. The reasons responsible for experimental performances of Q-switched Er:YAG lasers inferior to those predicted by the mathematical modeling are analyzed.
{"title":"Q-switched regime of 3-μm erbium lasers","authors":"S. Georgescu, V. Lupei, C. Hapenciuc","doi":"10.1117/12.312647","DOIUrl":"https://doi.org/10.1117/12.312647","url":null,"abstract":"A mathematical model, based exclusively on spectroscopic data concerning radiative, non-radiative, and energy transfer processes, is proposed and used to simulate the Q-switch regime of three-micron Er:YAG laser. The connection between the main energy transfer mechanisms that make possible generation on the self-saturated transition 4I11/2 yields 4I13/2 (up- conversion from 4I13/2 and 4I11/2, cross- relaxation from 4S3/2) and the giant pulse characteristics is discussed. The radiative as well as non- radiative losses during optical pumping and giant pulse generation are defined and evaluated. A particular attention is given to FTIR Q-switch which demonstrated real qualities for 3- micrometers Erbium lasers. The reasons responsible for experimental performances of Q-switched Er:YAG lasers inferior to those predicted by the mathematical modeling are analyzed.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"7 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":"115634341","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 relationship between statistical structure parameters of rough surface and associated correlation parameters of scattered field is used to develop a method for rough surface diagnostics. The treatment is based on the model of random phase object with inhomogeneity phase dispersion (sigma) 2qq(0) < 1. The proposed diagnostic methods are applicable to surfaces with roughness period comparable to the radiation wavelength employed, low-reflectance and arbitrarily shaped surfaces, and surfaces of a thin plane-parallel plate. The sensitivity limit of the methods in measuring the standard deviation of surface profile from base line is about 0.003 mm.
{"title":"Interference devices for noncontact diagnostics of arbitrarily shaped rough surfaces","authors":"P. Maksimyak","doi":"10.1117/12.312707","DOIUrl":"https://doi.org/10.1117/12.312707","url":null,"abstract":"The relationship between statistical structure parameters of rough surface and associated correlation parameters of scattered field is used to develop a method for rough surface diagnostics. The treatment is based on the model of random phase object with inhomogeneity phase dispersion (sigma) 2qq(0) < 1. The proposed diagnostic methods are applicable to surfaces with roughness period comparable to the radiation wavelength employed, low-reflectance and arbitrarily shaped surfaces, and surfaces of a thin plane-parallel plate. The sensitivity limit of the methods in measuring the standard deviation of surface profile from base line is about 0.003 mm.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"12 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":"131444996","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 vitro laser-induced fluorescence (LIF) spectra and lifetimes of normal and atherosclerotic tissues are reported. The experimental arrangement conceived to measure LIF contained a 700 ps nitrogen pulsed laser (337.1 nm) and two quartz optical fibers to induce and respectively collect the fluorescence of normal and diseased samples. With UV laser excitation we found proeminent differences both in spectral and temporal range between normal artery and atherosclerotic plaques which was standard pathological classified in five types such as: normal artery, fibrous plaque, atherosclerotic plaque, calcified plaque and ulcerated plaque. As for statistics, the total number of measurements performed on each of the five mentioned types of tissues was 25.
{"title":"Laser-induced fluorescence of atherosclerotic plaques","authors":"N. Moise, M. Pascu, C. Carp, C. Volvoreanu","doi":"10.1117/12.312652","DOIUrl":"https://doi.org/10.1117/12.312652","url":null,"abstract":"In vitro laser-induced fluorescence (LIF) spectra and lifetimes of normal and atherosclerotic tissues are reported. The experimental arrangement conceived to measure LIF contained a 700 ps nitrogen pulsed laser (337.1 nm) and two quartz optical fibers to induce and respectively collect the fluorescence of normal and diseased samples. With UV laser excitation we found proeminent differences both in spectral and temporal range between normal artery and atherosclerotic plaques which was standard pathological classified in five types such as: normal artery, fibrous plaque, atherosclerotic plaque, calcified plaque and ulcerated plaque. As for statistics, the total number of measurements performed on each of the five mentioned types of tissues was 25.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"48 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":"131457870","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}
I. Iova, M. Bazavan, C. Biloiu, G. Ilie, M. Bulinski
The molecular vibration temperature of the plasma from an interrupt arc discharge in air at atmospheric pressure and at current intensities in the range of 2 divided by 8 Amperes, using electronic and vibration bands of violet [B2(Sigma) + - X2(Sigma) +] and red [A2(Pi) - X2(Sigma) +] systems of the CN molecule was determined. At the equilibrium temperature of 6400 K, 27 lines of Ti, contained as impurity in coal electrode were found. These spectral lines were found in the 247 divided by 340 nm spectral range, having the upper levels of the excitation energies in the 3.60 divided by 5.69 eV range, in the neighborhood of the energy of dissociation of the CN molecule on the fundamental electronic state. Some considerations about the vibrational states populations are also made.
{"title":"Correlation of some radiative processes resulting from electronic and vibrational spectra of a CN molecule excited in an electric arc discharge","authors":"I. Iova, M. Bazavan, C. Biloiu, G. Ilie, M. Bulinski","doi":"10.1117/12.312822","DOIUrl":"https://doi.org/10.1117/12.312822","url":null,"abstract":"The molecular vibration temperature of the plasma from an interrupt arc discharge in air at atmospheric pressure and at current intensities in the range of 2 divided by 8 Amperes, using electronic and vibration bands of violet [B2(Sigma) + - X2(Sigma) +] and red [A2(Pi) - X2(Sigma) +] systems of the CN molecule was determined. At the equilibrium temperature of 6400 K, 27 lines of Ti, contained as impurity in coal electrode were found. These spectral lines were found in the 247 divided by 340 nm spectral range, having the upper levels of the excitation energies in the 3.60 divided by 5.69 eV range, in the neighborhood of the energy of dissociation of the CN molecule on the fundamental electronic state. Some considerations about the vibrational states populations are also made.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"42 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":"127031459","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. Balucani, Vitaly Bondarenko, G. Lamedica, A. Ricciardelli, A. Ferrari
The first successful attempt to integrate on-chip optical waveguides based on oxidized porous silicon and amorphous silicon photodetectors have been demonstrated. Buried channel waveguides were performed by thermal oxidation of porous silicon. Amorphous silicon photodetectors were fabricated on the waveguides. Different device structures as well as their performance attributes are exhibited. The devices were demonstrated to have photocurrent characteristics promising for optoelectronic applications.
{"title":"Amorphous silicon photodetectors for optical integrated circuits","authors":"M. Balucani, Vitaly Bondarenko, G. Lamedica, A. Ricciardelli, A. Ferrari","doi":"10.1117/12.312663","DOIUrl":"https://doi.org/10.1117/12.312663","url":null,"abstract":"The first successful attempt to integrate on-chip optical waveguides based on oxidized porous silicon and amorphous silicon photodetectors have been demonstrated. Buried channel waveguides were performed by thermal oxidation of porous silicon. Amorphous silicon photodetectors were fabricated on the waveguides. Different device structures as well as their performance attributes are exhibited. The devices were demonstrated to have photocurrent characteristics promising for optoelectronic applications.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"25 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":"126745514","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 theory of regular and chaotic self-pulsations in a CuCl crystal with the participation of coherent excitons and biexcitons is elaborated. The method of chaotic self-pulsation suppression in the system of coherent excitons and biexcitons is proposed. This method consists in action of external periodical turbulence upon a stochastic system. The range of amplitude values and frequencies of external harmonic pump were found at which the chaotic oscillation regime becomes nonlinear periodic by transformation of strange attractor into a limit cycle. The feasibility of observing the predicted effects in experiment is discussed.
{"title":"Appearance and suppression of stochastic self-pulsations of coherent excitons and biexcitons in condensed matter","authors":"V. Z. Tronciu, A. Rotaru","doi":"10.1117/12.312783","DOIUrl":"https://doi.org/10.1117/12.312783","url":null,"abstract":"The theory of regular and chaotic self-pulsations in a CuCl crystal with the participation of coherent excitons and biexcitons is elaborated. The method of chaotic self-pulsation suppression in the system of coherent excitons and biexcitons is proposed. This method consists in action of external periodical turbulence upon a stochastic system. The range of amplitude values and frequencies of external harmonic pump were found at which the chaotic oscillation regime becomes nonlinear periodic by transformation of strange attractor into a limit cycle. The feasibility of observing the predicted effects in experiment is discussed.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"126 44","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133085922","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. Ursache, V. Calian, M. Socaciu, C. Sarpe-Tudoran
We performed both experimental and theoretical studies on the laser radiation absorption coefficient of a copper surface. A theoretical model for the computation of the absorption coefficient was elaborated for two-layer case (metal-oxide), taking into account the nonlinear processes which govern the dynamics of the temperature and of the widths of the layers. The experimental data and the simulation results proved to be in a very good agreement.
{"title":"Nonlinear processes in laser radiation absorption on metallic surfaces","authors":"M. Ursache, V. Calian, M. Socaciu, C. Sarpe-Tudoran","doi":"10.1117/12.312797","DOIUrl":"https://doi.org/10.1117/12.312797","url":null,"abstract":"We performed both experimental and theoretical studies on the laser radiation absorption coefficient of a copper surface. A theoretical model for the computation of the absorption coefficient was elaborated for two-layer case (metal-oxide), taking into account the nonlinear processes which govern the dynamics of the temperature and of the widths of the layers. The experimental data and the simulation results proved to be in a very good agreement.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"93 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":"114567959","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}
V. Babin, M. Grigore, Laurentiu Cojocaru, S. Ersen, A. Moldovan
In this work we use a technique inspired by the inverse problem in the scattering theory, that is, the calculation of partial derivatives along the characteristic directions of the D'Alembert solution of the wave equation (Maxwell and Euler). In this way, we construct a system of stochastic non-linear differential equations. The analysis of this system, using algebraic invariants, gives more information in comparison with that given by Ghelfand-Levitan-Marcenko, in the inverse problem in the scattering theory.
{"title":"Construction of the first-order stochastic nonlinear differential equations in the modeling of stimulated scattering of optical fields","authors":"V. Babin, M. Grigore, Laurentiu Cojocaru, S. Ersen, A. Moldovan","doi":"10.1117/12.312799","DOIUrl":"https://doi.org/10.1117/12.312799","url":null,"abstract":"In this work we use a technique inspired by the inverse problem in the scattering theory, that is, the calculation of partial derivatives along the characteristic directions of the D'Alembert solution of the wave equation (Maxwell and Euler). In this way, we construct a system of stochastic non-linear differential equations. The analysis of this system, using algebraic invariants, gives more information in comparison with that given by Ghelfand-Levitan-Marcenko, in the inverse problem in the scattering theory.","PeriodicalId":383583,"journal":{"name":"ROMOPTO International Conference on Micro- to Nano- Photonics III","volume":"28 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":"116935967","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}
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