The Young's moduli of various oxide glasses (silicate, borate, phosphate, and tellurite) were measured using an ultrasonic method. To predict the Young's moduli of the oxide glass systems, empirical compositional parameters Gi and Vi, based on the Makishima-Mackenzie theory, were obtained, where Gi is the dissociation energy and Vi the packing density parameter of a single-component oxide. The relationship between the calculated Young's modulus from the compositional parameters and the measured Young's modulus was investigated. Experimental results indicated that the Young's modulus of phosphate and tellurite glasses could not be predicted using these parameters. Thus, it was necessary to modify the Gi, by considering P2O5 and TeO2 as glass network formers. As for the phosphate glass, it exhibited a layered structure that consisted of P=O double bond and three chains of P-O bond. In this paper, the modified Gi of P2O5 was calculated using the assumption that the P=O double bond is a nonbridging bond and does not contribute to Young's modulus. In the case of tellurite glass, the glass structure is mainly composed of TeO4 trigonal pyramids, and the addition of other oxides results in structural changes to the TeO3 trigonal pyramid. However, the mechanisms of such structural changes have not yet been clarified. Therefore, the modified Gi of TeO2 was calculated from the measured value using the density and Young's modulus of pure TeO2 glass. The results revealed that the calculated values using our proposed parameter were in good agreement with measured values all through the oxide glasses.

Young's Modulus and Compositional Parameters of Oxide Glasses

Linear optical properties of niobium-based tellurite glasses

Tellurite glasses. Part 1. Elastic properties

A semiconductor light emitting device is provided with a separately fabricated wavelength converting element. The wavelength converting element, of e.g., phosphor and glass, is produced in a sheet that is separated into individual wavelength converting elements, which are bonded to light emitting devices. The wavelength converting elements may be grouped and stored according to their wavelength converting properties. The wavelength converting elements may be selectively matched with a semiconductor light emitting device, to produce a desired mixture of primary and secondary light.

Semiconductor light emitting device with pre-fabricated wavelenght converting element

This review focuses on the engineering of the structural, thermal, optical and spectroscopic properties of tellurium oxide (TeO2) glasses for their applications in fibre optic and waveguide devices. Unlike silica optical fibres, tellurium oxide glass fibres and light waveguides support propagation of light beyond ∼2 μm, where silica fibres become opaque. Silica fibres also have limited solubility for rare earth oxides due to silica’s structure, which is where tellurium oxide fibres and light waveguides can offer significant opportunities to engineer novel lasers and amplifiers for integrated optics. In this review, we compare the structural properties of TeO2 based glasses, modified by incorporating alkali, alkaline earth, and other oxide compounds. Based on Raman, UV, visible and infrared spectroscopic data, the structural aspects of tellurite glasses are discussed. The effects of compositional modification on the thermal and viscous flow properties are also compared and related with the resistan...

Review on structural, thermal, optical and spectroscopic properties of tellurium oxide based glasses for fibre optic and waveguide applications

The refractive index of binary tellurite glasses with various modifiers was measured down to the fifth decimal place in the wavelength range of 0.40-1.71 μm using the minimum-deviation method. An empirical equation based on the single-oscillator Drud-Voigt dispersion equation, n d 2 =A.Nfλ 0 2 +B, is obtained, where n d is the refractive index at 0.5876 μm, N is the number of molecules in a unit volume, f is the average oscillator strength, λ 0 is the average resonance wavelength, and A and B are constants. The refractive index n d of tellurite glasses is substantially determined by the resonance wavelength at the ultraviolet region, which is affected by the main constituent, TeO 2

Shigeru Pujino

Papers

Refractive-Index Dispersion of Tellurite Glasses in the Region from 0.40 to 1.71 μm