The article presents a model of LED lighting fixture. Component LED sources emit light in the range of red, green and blue. To mix the luminous flux from a particular sources, a cylindrical mixer made of PMMA was used. Furthermore, the paper presents the mathematical foundations of the light-mixing algorithm derived from the three different colored sources.
This article presents basic metrological properties of selected integrated color sensor models. The study involved MTCSiCS and MMCS6 sensors, produced by MAZeT. Describes electronic circuits necessary for reading data from the color sensor. The analysis shows the relative characteristics of spectral sensitivity of the detectors, the linearity characteristics of the output signal as well as the useful range.
LED modules emitting a luminous flux, implement near-field luminance distribution or colorimetric distribution depending on emitters location. In the far field there is complete mixing of luminous flux, both in terms of quantity as well as because of distribution color parameters. To achieve these mixing light in a short distance of the LEDs is necessary to use optical elements. The article presents the results of creating light distribution and luminance by using the ring optical elements with truncated outer surfaces.
During the past years significantly increased the number of LED models available on the market. However, not all of them have parameters which allow for use in professional lighting systems. The article discusses the international standards which should be met by modern LEDs. Among them, one of the most important parameters is factor of luminous flux decline in value during the operation of the LEDs. Its value is influenced by many factors, among others, the junction temperature of the diode and average and maximum values of supply current. Other important, for lighting reasons, parameters are stability of correlated color temperature and stability of chromaticity coordinates of the emitted light. The paper presents a system to measure luminous flux and colorimetric parameters of LEDs. Measurement system also allows for measuring a change in these parameters during operation of the LED.
In this paper the off-grid photovoltaic system consisting of a PV panel, MMPT charge controller and battery is described. The realization of a laboratory stand for charging or discharging batteries is presented. Original monitoring and control system, which is based on LabVIEW software and LabJack DAQ device, has been built. Data acquisition part, arithmetic part and front panel of program created in LabVIEW are described. Some problems with implementation of this system, providing the monitoring of electrical parameters, are mentioned.
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.