In the paper thermal and luminescence properties of phospho-tellurite glass and glass after thermal treatment doped with NdF<sub>3</sub> were presented. The crystallization kinetic of the main crystallization peaks of glass was investigated using differential scanning calorimetry (DSC). The value of the activation energy for crystalline phase (E<sub>c</sub> 54,21 ± 5 kJ mol<sup>-1</sup>) was calculated using <i>Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS), Starink</i> and<i> Tang</i> methods. The glass-ceramic was obtained by heat treatment method. The luminescence transitions from levels <sup>4</sup>F<sub>5/2</sub> → <sup>4</sup>I<sub>9/2</sub> (878 nm), <sup>4</sup>F<sub>3/2</sub>→<sup>4</sup>I<sub>11/2</sub> (1058 nm), and <sup>4</sup>F<sub>3/2</sub> → <sup>4</sup>I<sub>13/2</sub> (1330 nm) in glass and glass-ceramic doped NdF3 were compered.
This paper describes electrical method for measuring junction temperature of high power LEDs. Designed and
constructed system with thermal chamber and performed a number of studies in typical operating conditions luminaires
with LEDs. The results allow for proper construction of a complete LED lighting system using for operation in ambient
temperatures ranging from -10ºC to 100ºC, especially in terms of matching the effective supply.
In the paper the influence of luminescent layer made of tellurite glass doped with Yb<sup>3+</sup>/Er<sup>3+</sup> on parameters of
silicon photovoltaic cell in the near infrared region was investigated. Luminescence properties of the fabricated
glass under 976 nm excitation were measured. As a result of the conducted works enhancement of conversion
efficiency of NIR radiation utilizing upconversion process in tellurite glass doped with RE was obtained.
Parameters of PV cell with active layer: open circuit voltage increase of 5,5% for sample codoped with Yb<sup>3+</sup>/Er<sup>3+</sup>
system and 2,7% for sample doped with Er<sup>3+</sup>, 100% is the signal from pure PV cell illuminated by 976 nm laser.
In this paper the analysis of upconversion luminescence dynamics in tellurite and germanate glasses doped with
Ho<sup>3+</sup> and sensitized by Yb<sup>3+</sup> in 8:1 molar ratio was presented. Population of energy levels was calculated using
Runge-Kutta method. The influence of pump power (976 nm) radiation on population of excited levels and the
possible upconversion mechanisms were analyzed. The energy transfer coefficient in tellurite glass C<sub><sup>D2</sup></sub> = 5,0 x
10<sup>-18</sup> cm<sup><sup>3</sup></sup>/s, C<sub>D3</sub> = 1,5 x 10<sup>-17</sup> cm<sup>3</sup>/s and C<sub><sub>D4</sub></sub> = 9,0 x 10<sup><sup>-17</sup></sup> cm<sup>3</sup>/s and in germanate glass C<sub>D2</sub> = 2,80 x 10<sup>-18</sup> cm<sup>3</sup>/s,
C<sub>D3</sub> = 6,35 x 10<sup>-18</sup> cm cm<sup>3</sup>/s and C<sub>D4</sub> = 3,56 x 10<sup>-17</sup> cm<sup>3</sup>/s were used to analyze dynamics of upconversion processes.