Gas discharge lamps, this meaning lamps using the principle to make a gas electrically conductive and thereby light emitting, are a relatively old technique. Especially fluorescent lamps represent a very widespread lighting system. It is not possible to apply the line voltage directly to such lamp, be it AC or DC, a higher or a lower magnitude. Traditionally these lamps have always been operate...

In this paper will be reported the study and implementation of a single stage High Power Factor (HPF) electronic ballast for High Pressure Sodium (HPS) lamps using a Half-Bridge Boost Rectifier integrated with an Electronic Ballast based in a LCC filter. In the recent years many authors are working to obtain single stage HPF electronic ballast for fluorescent lamps [1-3]. Normally to obtain HPF...

The Safety Technology Authority (TUKES) organized EMC market surveillance tests on 36 energy-saving lamp models, according to the standard EN 55015. First of all, conducted disturbance emissions at mains ports were tested for. The first test results showed that 10 lamps out of 36 did not pass the tests and that there were serious defects in three lamp types. Surprisingly, defects were found to ...

In order to solve the problems of large energy consumption existing in tunnel lighting control system, an automatic control system of tunnel lighting is designed based on stepless control method. The tunnel lighting control model is established based on “Specifications for Design of Ventilation and Lighting of Highway Tunnel (China)”. Simulation of tunnel lighting control based on the establish...

Light spectroscopy in the frequency-domain has been used to study the optical properties of biological tissues. We have analyzed the possibility of using light emitting diodes (LEDs) as intensity modulated light sources for frequency-domain spectroscopy. The use of LEDs presents several advantages: one LED's output covers a spectral region of about 80 nm, and commercially available LEDs allow f...

The aim of our study was to determine the impact of medium-pressure UV lamps radiation on water quality in a chlorinated indoor swimming pool. An indoor swimming pool was equipped with two medium-pressure UV lamps. We collected eight samples of water daily over a four-weeks period and measured total and free chlorine, pH, water temperature, bacteriological parameters, total organic carbon and t...

Artificial lighting allows humans to be active at night, but has many unintended consequences, including interference with ecological processes, disruption of circadian rhythms and increased exposure to insect vectors of diseases. Although ultraviolet and blue light are usually most attractive to arthropods, degree of attraction varies among orders. With a focus on future indoor lighting applic...