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Simple and easy to fabricate sensors with high sensitivity, high quality-factor $(\chi)$ , large figure of merit (FOM), and narrow bandwidth are highly desirable for immediate point of care testing. In this article, we introduce a one-dimensional periodic array of barium flint glass on active plasmonic material, a thin gold film on silicon nitride (Si3 N4) substrate. Reflection spectrum of the proposed structure exhibits a clear rejection of certain wavelength on normal incidence due to the coupling between incident plane wave and plasmonic wave. The effect of ambient refractive index or glucose concentration has been studied to measure the plasmonic sensitivity of the designed structure in blood glucose detection. After optimizing geometric parameters, the designed sensor achieved sensitivity and quality factor as high as ~ 2600 nm RIU −1 (refractive index unit) and ~1500 respectively. The calculated sensitivity, quality factor and FOM are much higher than the reported structures with a similar geometry in IR. Owing only one rejection band with narrow bandwidth, the designed structure can also be realized for optical filtering applications. Wide spectral tunability in the IR, close to 100% peak absorbance and narrow bandwidth make the designed structures as an ideal candidate for surface-enhanced infrared absorption (SEIRA) spectroscopy.

Of late, metallic nanowires (NWs) are gaining much interest as alternative coating materials for various optical fibres and lenses. In the present study, a first principles based approach was employed to calculate the electronic band structures, total and partial density of states (TDOS and PDOS) and various optical characteristics of Sb/GaAs core/shell (c/s) NW. The exterior atoms of the c/s NW were passivated with hydrogen atoms to prevent the occurrence of dangling bonds. The band structure showed metallic characteristic of the NW, using generalized gradient approximation (GGA). The TDOS and PDOS calculations predict that the metallic nature is due to the contributions by the Sb-5p states at the Fermi level. The refractive index (R.I.) values in the visible (VIS) region were in the range of the R.I. values for the case of flint glass, enabling the use of these NW arrays as coating materials for various optical lenses. The low absorbance values in the infrared (IR) region, coupled with reflectance intensities much less than some traditional glass mirrors, suggest the possible applications of these NWs as cold anti-reflective coating materials for optical fibres and cables.

Neke optički neaktivne tvari mogu postati optički aktivne u prisustvu magnetskog polja. Elektromagnetsko zračenje se prolaskom kroz transparentne tvari s velikom dielektričnom permitivnošću u prisustvu vanjskog magnetskog polja, kao posljedica optičke aktivnosti, očituje u zakretanju ravnine polarizacije što je poznato kao Faradayev efekt. Mjereni su kutovi zakretanja ravnine polarizacije svijetlosti valnih duljina 405 nm, 450 nm, 532 nm i 650 nm za kristale optičkog stakla (kvarc), kalcijevog klorida (KCl), natrijevog klorida (NaCl) i kalijevog bromida (KBr) te za maslinovo ulje Olivenö𝑙̈ – Roth. Kut zakreta ravnine polarizacije svjetlosti proporcionalan je s magnetskim poljem, duljinom uzorka te konstantom poznatom kao Verdetova konstanta. Cilj rada bio je izmjeriti Verdetovu konstantu za gore spomenute materijale te usporediti eksperimentalno dobivene vrijednosti s eventualnim teorijskim vrijednostima. Some optically inactive substances can become optically active in the presence of a magnetic field. Electromagnetic radiation, by passing through transparent substances with a high dielectric permittivity in the presence of an external magnetic field, as a consequence of optical activity, is manifested in the rotation of the plane of polarization known as the Faraday effect. The angles of rotation of the plane of polarization of light of wavelengths 405 nm, 450 nm, 532 nm and 650 nm were measured for the crystals made of flint glass, calcium chloride (KCl), sodium chloride (NaCl) and potassium bromide (KBr), and for olive oil Olivenö𝑙̈ - Roth. The angle of rotation of the plane of polarization of light is proportional to the magnetic field, the length of the sample, and a constant known as the Verdet constant. The goal of this thesis was to measure the Verdet constant for the above-mentioned materials and to compare the experimentally obtained values with possible theoretical values/models.

Ο άνθρωπος χρησιμοποιεί το γυαλί από αρχαιοτάτων χρόνων, αρχικά για την κατασκευή όπλων, εργαλείων και διακοσμητικών με τον οψιδιανό (φυσικό γυαλί) και στη συνέχεια με την παρασκευή του, καθιερώνοντας το ως κύριο υλικό συσκευασίας καθώς και σε διακοσμητικά και επιτραπέζια είδη. Στο γυαλί νατρίου-ασβεστίου αναλογεί το 90% της συνολικής παραγωγής του γυαλιού στην Ευρώπη καθώς τα πιο ευρέως χρησιμοποιούμενα αντικείμενα κατασκευάζονται από αυτό. Τα ιδιαίτερα φυσικοχημικά χαρακτηριστικά του το καθιστούν αναντικατάστατο σε πληθώρα εφαρμογών (ιατρική, αρχιτεκτονική, ενέργεια, αεροναυπηγική, τρόφιμα, τεχνολογία πληροφοριών).Καίτοι το γυαλί είναι 100% ανακυκλώσιμο, η υαλουργία που απορροφά το μεγαλύτερο μέρος του αναγκάζεται να απορρίψει μεγάλες ποσότητες λόγω α) ξένων προσμίξεων (μέταλλα, κεραμικά, χαρτί) και β) της ύπαρξης πολυχρωματικού υαλοθραύσματος το οποίο καθιστά απαγορευτική τη χρήση του στην παραγωγή λευκού γυαλιού. Επομένως, θεωρείται απαραίτητη η επαναχρησιμοποίηση του σε ήδη υπάρχοντα προϊόντα καθώς και σε καινοτόμα υλικά και εφαρμογές. Σημαντική παράμετρος είναι ο καθορισμός της ποιότητας της επιφάνειας του υαλοθραύσματος εφόσον αυτή θα έρθει σε επαφή ή ακόμη και θα αντιδράσει με άλλα υλικά και κατά συνέπεια το ποσοστό αλλοίωσης ή διάβρωσης που έχει υποστεί, ώστε να γίνεται αποτελεσματικότερη «απορρόφηση» του υαλοθραύσματος από τα νέα υλικά. Αντικείμενο της παρούσας διατριβής είναι η αποτύπωση της φθοράς που έχουν υποστεί οι γυάλινες επιφάνειες και επομένως η διερεύνηση των περιβαλλοντικών παραγόντων που υποβαθμίζουν την ποιότητα των γυάλινων επιφανειών από την παραγωγή τους, την αποθήκευσή τους μέχρι και τη συλλογή τους σε χώρους ανακύκλωσης. Απώτερος στόχος με γνώμονα τη συμπεριφορά τους στα διάφορα διαβρωτικά περιβάλλοντα, είναι η μείωση των ποσοτήτων των αποβλήτων με την περαιτέρω χρήση τους ώστε να προωθηθούν ως πόροι επιτυγχάνοντας υψηλότερα επιπέδα ανακύκλωσης όπως αυτά που επιβάλλει η πολιτική διαχείρισης αποβλήτων της Ευρωπαϊκής Ένωσης. Πρωτοτυπία της διατριβής αποτελεί:i)η εξέταση τριών ποιοτήτων υαλοθραυσματος με διαφορετικό ποσοστό πρότερης διάβρωσης (γραμμή παραγωγής, εξωτερικοί χώροι αποθήκευσης υαλουργίας, εγκαταστάσεις ανακύκλωσης γυαλιού) και για τα 4 χρώματα που παράγει η υαλουργία (λευκό, πράσινο, καφέ, μπλε) στη συμπεριφορά τους αφενός μεν σε περιβαλλοντικούς παράγοντες, δίδοντας μία απάντηση στην επίπτωση του χρόνου και του τρόπου αποθήκευσης στη βιομηχανία, αφετέρου η καταγραφή του μηχανισμού περαιτέρω διάβρωσης κατά την επαναχρησιμοποίηση τους. ii)η μελέτη της συμπεριφοράς και της επίδρασης στις μηχανικές ιδιότητες κονιαμάτων όταν το δομικό προϊόν βρεθεί σε περιβάλλον φωτιάς καθόσον στο χώρο των δομικών υλικών, ο οποίος αποτελεί το δεύτερο τομέα χρήσης υαλοθραύσματος εκτός αυτού της υαλουργίας, είναι σημαντικός παράγοντας.iii)Η χρήση του ζ-δυναμικού ως «εργαλείο» για τον καθορισμό του χρώματος και της ποιότητας του υαλοθραύσματοςΠρωταρχικό στάδιο απετέλεσε ο προσδιορισμός της χημικής σύστασης των δειγμάτων καθώς και οι βασικές φυσικές και μηχανικές ιδιότητες τους.Στη πρώτη σειρά πειραμάτων και για να εξεταστεί το “worst case scenario” χρησιμοποιήθηκαν λειοτριβημένα δείγματα (

In this preliminary study, the effect of glass powder content at early age compressive strength and its effect at strength retention coefficient during water immersion period on magnesium silicate hydroxide cement pastes on carbonation curing was investigated. A magnesium oxide-rich powder with a maximum grain size of 150 μm was used, as well as, a waste glass powder with a maximum grain size of 250 μm, which was obtained from grinded flint glass bottles. Cement pastes were produced with 0, 10, 20, 30, 40, and 50 glass powder weight percentage. The specimens were compacted into cubic moulds (e = 20 mm) under 70 MPa and, subsequently, cured on accelerate carbonation chamber for 2h at >99% CO2 concentration. The compressive strength was determined 3 days after CO2, period which the specimens were preserved on room conditions (20∘C and 60%RH), and also at 3, 7 and 14 days of water immersion period. Comparison of the results obtained for different mixing compositions, as well as, different water immersion periods are discussed in this work.

This article discusses the properties of different diamagnetic and paramagnetic materials for a basic current/magnetic field sensor system set up with different relative orientations of analyzers and polarizers. The paper analyzes linearity ranges of different materials and their sensitivity for different wavelengths. Terbium doped glass (TDG), terbium gallium garnet (TGG), doped TGG and dense flint glass materials are used for analysis based on Faraday's rotation principle. TGG shows high Faraday rotation, temperature stability and high optical quality. Three ranges of the magnetic field have been chosen for performance analysis. The study reveals that doping of praseodymium (Pr3+) on TGG exhibits a better response at 532 nm as well as 1064 nm wavelengths than TGG. At 632.8 nm wavelength, cerium (Ce3+) doped terbium aluminum garnet (TAG) ceramic exhibits better resolution than others. The study has been done for performance analysis of different MO sensors applicable for measurement of various process parameters like current, displacement, and magnetic field.

Due to the sizable refractive index of lead halide perovskites, reflectivity off their interface with air exceeds 15%. This has prompted a number of investigations into the prominence of photoreflective contributions to pump–probe data in these materials, with conflicting results. Here we report experiments aimed at assessing this by comparing transient transmission from lead halide perovskite films and weakly quantum confined nanocrystals of cesium lead iodide (CsPbI3) perovskite. By analyzing how complex refractive index changes impact the two experiments, results demonstrate that changes in absorption and not reflection dominate transient transmission measurements in thin films of these materials. None of the characteristic spectral signatures reported in such experiments are exclusively due to or even strongly affected by changes in sample reflectivity. This finding is upheld by another experiment where a methyl ammonium lead iodide (MAPbI3) perovskite film was formed on high-index flint glass and pro...

Radiation-resistant optics, which is necessary to transfer light from plasma to detectors in ITER, will be exposed to neutron fluxes at D-T stage. Achromatic lenses located in the interspace and in the port cell areas must have a sufficient optical radiation hardness to sustain a neutron irradiation without significant degradation of transmittance in as wide spectral range as possible. They will be made of two types of glass: KU1 fused silica and a flint glass. The radiation hardness of the candidate flint glasses under neutron irradiation to ITER-relevant doses has to be investigated.Six types of the commercial Ce-doped flint glasses have been irradiated in a nuclear reactor up to fluencies of the fast neutrons (E > 0.1 MeV) within the range of 1012 − 1016 n/cm2. F108 and TF200 types have demonstrated the most prominent results. F108 type has a high transmittance in the visible region and a sufficient radiation hardness to be recommended for use in the port cell. TF200 type has a limited spectral range, but it has shown the best radiation hardness at a fluence of 1016 n/cm2. It can be used in the interspace area if a low transmittance in the violet-blue region is not an issue. Keywords: Flint glass, Radiation hardness, Neutron irradiation, ITER

New glasses in the composition 60Sb2O3-(40-x) NaPO3-xWO3 (where x = 0 to 40 mol.%) were prepared using the melt quenching technique. Different physical properties were measured to explain the effect of replacing NaPO3 with WO3. Differential scanning calorimetry (DSC) measurements showed high thermal stability, with Tx-Tg ∼ 100–130 °C. Glass transition temperature, Tg increased with an increasing amount of tungsten oxide. Such increase is also observed for the measurement of density, micro hardness, and the elastic moduli (longitudinal modulus (L), shear modulus (G), bulk modulus (K), and Young's modulus (E)). However, Poissn's ratio remains practically invariant and close to 0.252 confirms the bi-dimensional structure. The insertion of WO3 reduces the optical band gap and increases the refractive index from 1.584 to 1.786 at 486.1 nm where x WO3 is from 0 to 25 (mol.%). Furthermore, the measured optical dispersion changes from low dispersion crown glass to more dispersive flint glass. Following these various results, the glasses studied prove to be potential candidates for optical devices.

Achromats are one of the most commonly used optical components in optical design and engineering. Historically, an achromat is composed of two lenses: a positive crown glass element and a negative flint glass element, cemented together. The compound lens brings at least two wavelengths of light to a common focus along the optical axis. Presented in this paper is the novel implementation of an achromatic singlet made of a single optical material, Zeonex E48R. A customized ray tracing algorithm was used to arrive at the solution while single point diamond turning is used to fabricate a series of prototypes. Axial MTF and chromatic focal shift data are presented alongside two similar comparison lenses: a plano-convex lens and a traditional cemented achromatic doublet. The test results illustrate achromatic performance can be achieved using a single optical material with axial performance that exceeds an incumbent cemented achromat with the same first order properties of focal length and lens diameter. Applications for the new singlet achromatic lens design form include broadband focusing, high laser power uses, and ultraviolet applications where optical cement is not desired. Keywords

White wines from two vintages were bottled in green and flint glass bottles and stored under typical supermarket shelf conditions. Light-strike fault, colour changes, light and temperature exposure were monitored up to 50 days. In general, green glass bottles secured wine quality for the tested period. Only a few flint glass bottled wines developed a fault due to light-strike after 1–2 days of supermarket shelf life, but all developed the fault after 20–40 days; so we considered the possibility of two mechanisms causing the problem. Flint-glass bottled wines stored on the bottom shelf developed the defect only slightly later compared with the wines on the top shelf. Moreover, storing the wines in dark and cold after a period of exposure to light did not eliminate the fault, indicating that the defect is probably additive. Monitoring the amount of light to which wines are exposed could prevent the fault.

Based on previous theoretical studies, an oblique-incidence quarterwave phase retardation rhomb is realized and calibrated. The rhomb is made of flint glass (n = 1.7000 at 589 nm). In the wavelength interval 400–950 nm, the retardance varied between 87.98° and 88.10°. Deviation from the design retardance value of 90° resulted from the formation of surface layers on the rhomb faces, polishing effects and internal stresses. The retardance could be adjusted to ∼90° by a small variation in the external angle of incidence. Achromaticity of this type of rhombs implies using high refractive index glasses (n > 1.6).

Ternary layer-based one-dimensional photonic crystal (1D PC) kind of optical filter is discussed that operates in the visible and near-infrared regimes of the electromagnetic spectrum. The 1D PC filter is comprised of bimetallic structure having three periodic nanolayers of gold, flint glass (SiO2), and silver. Dispersion and reflection characteristics of the proposed filter are analyzed by implementing the concept of transfer matrix and taking into account the incidence excitations under different angles. It is found that the structure exhibits behavior similarly to notch, comb, and Fabry–Perot types of filter. It is expected that such filters would be useful in integrated optic as well as in sensing applications.

An external voltage has been applied across the capacitor configuration formed by two parallel aluminium plates with dielectric material in between, provides enough energy to the dielectric dipoles in order to shift the wavelength of the incident laser on that dielectric surface toward smaller values [1]. This change in optical property could be responsible for the change of relative permittivity of the dielectric surface which can be used as optical switch or waveguide. In this work, a flint glass prism is used as a dielectric medium whose index of refraction is 1.6242 and the Brewster angle is 58.388 degree for 532nm green diode laser.

This paper discusses the properties of magneto-optic materials and its sensitivity with a wavelength in a basic current/magnetic field sensor setup for different relative orientation between analyzer and polarizer angle. TDG, TGG, doped TGG, YIG, and dense flint glass materials were used for characteristics analysis. Faraday rotation is inversely proportional to wavelength. TGG shows larger rotation, a high stability to temperature change as well as high optical quality. Pr3+-doped TGG has been observed to exhibit the maximum sensitivity with a change in analyzer angle at 532 nm as well as 1064 nm. At 632.8 nm Ce3+ doped TAG ceramic shows maximum sensitivity. The MO sensors are used for various process parameters measurement such as current, displacement, magnetic field, etc.

The most important properties of optical glass types are transmission and dispersion. All other properties are second priority. Sometimes however, such glasses might have to endure high mechanical loads. Examples are with cameras subject to strong accelerations such as rocket launches loads or thermal stresses induced by temperature changes. Optical glasses also find use as windows with pressure loads. In such cases the question arises, which loads are allowable to prevent breakage and how can the strength of given optical elements be increased. In the last ten years considerable progress could be achieved in reliably predicting lifetimes of structures made from the glass ceramic ZERODUR. This work will show the transfer of the knowledge gained to optical glasses. The breakage stress threshold observed with ZERODUR exists also with optical glasses. We will show its usage for assessing short time loads and long-time loads taking into account the fatigue effect. The article will provide all available strength data and discuss how to estimate data for glass types without existing measurement results. For the lead flint glass types there is a good correlation of the breakage stress threshold with their lead content allowing predicting threshold values for all glass types in this glass type family.

First, a theoretical analysis was performed on the effect of temperature on the performance of the sensing element of paramagnetic rare earth-doped magneto-optical glass material that can be used in an optical current transducer application. The effect comprises two aspects: the linear birefringence and the Verdet constant. On this basis, rare earth-doped glass temperature characteristics were studied, and the experimental results indicated that the linear birefringence of rare earth-doped glass increased with increasing temperature, while its magneto-optical sensitivity decreased. Comparative experiments performed for various concentrations of rare earth dopant in the glass revealed that changes in the dopant concentration had no significant effect on the performance of magneto-optical glass. At last, a comparison between rare earth-doped magneto-optical and diamagnetic dense flint glass showed that the sensitivity of the former was six times that of the latter, although the temperature stability of the former was poorer.