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The operating characteristics of small-wattage metal halide lamps (35W, 70W, and 150W) are investigated. Included are acoustic resonance, luminous efficacy, and electrical characteristics at steady state. A laboratory electronic ballast is built to operate metal halide lamps with square-wave currents in a frequency range from 50 Hz up to 50 kHz. The operating frequency, amplitude and dead-time can be adjusted independently. Experimental results show that the luminous efficiency decreases slightly as the operating frequency increases but deteriorates considerably as the lamp power is reduced. By examining the acoustic resonance spectra, it is found that the lamp arc instability is highly related to the dead-time of the inverter. The investigated results provide useful information for the design of the electronic ballasts.

A solar fiber optic lighting system, SP3 from the Swedish company Parans Solar Lighting AB, has been installed in a study area/corridor test site. A collector is tracking the sun during daytime, focusing the direct sun irradiance via Fresnel lenses into optical fibers, which guide the solar light into the building. The illumination properties of the system have been characterized. The energy saving due to reduced need of artificial lighting have been calculated and methods for balancing the artificial lights in the test site have been evaluated. The illumination at the test site using solar light was at least as high as when using the artificial lights and even higher at very clear days. The luminous flux output (500 lm) was somewhat lower than specified by the manufacturer (550 lm) at 100 000 lx direct sun illuminance. The output at 130 000 lx was high 767±33 lm the sunlight coupling efficiency 23 %. However, for a 20 m SP3 system the luminous flux output (400 lm) at 100 000 lx was higher than specified (350 lm). The SP3 system of Parans provides high quality solar light. It has a fuller spectrum close to the spectrum of the sun compared to the fluorescent lights at the test site. The correlated color temperature of the system was 5800±300 K and the color rendering index 84.9±0.5. The lighting energy saved due to decreased need for artificial light was estimated to 19 % in Uppsala which has 1790 annual sun hours. The savings in Italy, which has 3400 sun hours, is 46 %. Additional saving, especially in warmer countries can be obtained due to decreased need for cooling in the building as the solar luminaires provide negligible heat to the indoor air. Economical saving could also be realized by improved well-being of the occupants spending time under the solar luminaires. Three ways of balancing the artificial light due to sunshine fluctuations have been investigated. The global horizontal irradiance could not be used as a control signal for balancing the artificial lights but a pyranometer attached to the SP3 sun tracking collector was usable. Also the signal from an indoor luxmeter sensor could be used for balancing the light. However the signal from the light sensor which makes the SP3 collector to track the sun is probably the most cost effective method as it would serve two purposes; tracking the sun and balancing the artificial lights.

This master´s thesis is about searching for a connection between solar illumination and solar irradiance. The task is attempt to find out if it is possible to use one factor in order to determine the other one. Part of this thesis deals with cooling of virtual building.

The thesis is divided into several parts. The first part is theoretical and its main focus is the description of public lighting and the theory regarding lighting technology. The second part continues with the research of the current state in Bezděkov village. The thesis further describes the proposal for the village public lighting with the use of HPS and LED technology, where village models are made for both options to show the requested result. The last part of the work deals with cables dimensioning, the selection of the most effective regulations for lighting, and finally the economic assessment of both projects, while both the investment expenses and the public lighting service fees for the next 20 years are included.

This thesis deals with the processing of light technical parameters and performance of key LED chips for their applications in lighting systems. The aim is to create a laboratory model for measuring the qualitative and quantitative parameters of highly luminous light LED emitted depending on the angle, using a spherical integrator 0.3 m, goniometer and fiber spektroradiometr /luxmeters. Goniometer is designed using modular optomechanical parts company Thorlabs. Due to the current passing through the LED chips heat up considerably. To light LED chip parameters tested were not affected by heat from the chip is required to pay the heat generated by a passive radiator. Another part of this thesis is the reconstruction of an older model spherical integrator. Reconstruction must be undertaken so as to ensure sufficient cooling again tested LEDs. Light scattered in the ball of the integrator is led by the optical cable to the spektroradiometr that are subsequently recorded its parameters. The second element used to measure the light produced by the LED source is photocell. Spherical integrator must be appropriately modified to indicate the two measuring elements and also meet the standards of determining the correctness of measurement. At the end of the measurement results will be compared with catalog values provided by the manufacturer.