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In this paper the analysis and assessment of the existing lighting system in one of the students’ dormitories in Warsaw is presented. It is one of the first steps of the project “Thermo-modernization of two chosen public buildings according to nZEB standards”. We characterized the analyzed building focusing on the characteristics of the interiors and lighting equipment used. The study covered a detailed inventory of the lighting system as well as the measurements of illuminance distributions on task areas in the interiors. On the ground of the results the levels of the average illuminance and illuminance uniformity on task areas in the interiors were calculated, analyzed and compared with the required values for this type of facility. The levels of the lighting installed power density and normalized power density in the interiors were calculated and analyzed either. Moreover, the installed power density and total annual energy density for the lighting system in the building were calculated. On the ground of the results the lighting energy efficiency for the analyzed building was stated. The results of the lighting conditions and its energy efficiency assessment are a reference to the planned in the further studies lighting proposals to improve the quality of the luminous environment in the interiors and energy standard in the dormitory.

Der Band thematisiert die besonderen Bedingungen des deutsch-polnischen Sprachkontakts auf deutscher und polnischer Seite. Dieser Spezifik entsprechend ist das Buch gegliedert in die thematischen Schwerpunkte «Potenzial von Zweisprachigkeit und Einstellungen zur Zweisprachigkeit, Linguistische Untersuchungen zur Zweisprachigkeit und Grenzregion und Mehrsprachigkeit».Das Buchprojekt ist in Kooperation deutscher und polnischer Linguisten entstanden und geht auf eine Sektionentagung der Gesellschaft für Angewandte Linguistik (GAL) zurück. Dass die Autorinnen und Autoren ihre Beiträge auf Deutsch und Polnisch verfasst haben, steht programmatisch für die Intention dieser Publikation: Interesse zu wecken für die Spezifik des (zu) wenig beachteten deutsch-polnischen Sprachkontakts.

Agriculture is one of the most important areas of the world economy. However, due to dependency on weather conditions, it is strongly industrialized, for example by introducing additional lighting improving the efficiency of plants growth. Construction and operation of light-emitting diodes provides new possibilities in research and application of new concepts in agricultural lighting. The aim of the work was to investigate the effect of various spectra of light on the efficiency of photosynthesis and the growth of selected species of plants. For this purpose two grow-boxes with dedicated LED-based lighting systems were constructed and placed in the darkroom with controlled temperature. In each box lighting system provided different spectral composition of light and it was possible to adjust the ratio of blue and red as well as the irradiance level. In the paper we present the construction of the grow-boxes and the results of 3 cycles of experiments conducted with this system. During the first cycle two groups of tested plants were cultivated in the LED grow-boxes with constant irradiance level and the third group in natural light conditions. During the second cycle the irradiance in both boxes was gradually increased from 8 W/m2 to 38 W/m2. During the third cycle the irradiance was set to 38 W/m2 during the whole period (max power MRED module) to get the maximum possible intensity of photosynthesis.

Development of light-emitting diodes has brought new possibilities in many applications, especially in terms of flexible adjustment of light spectra. This feature is very useful in construction of many devices, for example for medical diagnosis and treatment. It was proved, that in some cases LEDs can easily replace lasers during therapy of cancer without reduction of efficiency of this process. On the other hand during diagnosis process LED-based constructions can provide unique ability to adjust the color temperature of the output light while maintaining high color rendering. It allows for optimum surface contrast and enhanced tissue differentiation at the operator site. In the paper we describe the construction of the tunable LED-based source designed for application in endoscopy. It was optimized from the point of view of the color rendition for 5 different correlated color temperatures (illuminant A, D55, D65, 3500K and 4500K) with the restriction of very high (>90) values of general and specific color rendering indexes (according to Ra method). The source is composed of 13 light-emitting diodes from visible region mounted on the common radiator and controlled by dedicated system. Spectra of the components are mixed and the spectra of output light is analyzed. On the basis of obtained spectra colorimetric parameters are calculated and compared with the results of theoretical analysis.

The article proposes a method for measuring discomfort glare which uses numerical description of the phenomenon in the form of a digital luminance distribution map recorded on a CCD array. Essential procedures for determining partial quantities which are necessary for calculation of UGR index are discussed in detail, along with techniques for measuring position index and size of light sources, with regard to the parameters of the registering system and coordinates of the images of the sources on the array.

Semiconductor emitters are used in many areas of medicine, allowing for new methods of diagnosis, treatment and effective prevention of many diseases. The article presents selected areas of application of semiconductor sources in UVVIS- NIR range, where in recent years competition in semiconductor lasers and LEDs applications has been observed. Examples of applications of analyzed sources are indicated for LLLT, PDT and optical diagnostics using the procedure of color contrast. Selected results of LLLT research of the authors are presented that were obtained by means of the developed optoelectronic system for objectified irradiation and studies on the impact of low-energy laser and LED on lines of endothelial cells of umbilical vein. Usefulness of the spectrally tunable LED lighting system for diagnostic purposes is also demonstrated, also as an illuminator for surface applications - in procedure of variable color contrast of the illuminated object.

Improvement of energy efficiency in buildings is the goal of many activities around the world. In recent years a need to increase the number of buildings, which not only fulfil the minimum energy performance requirements, but have very low energy consumption and are environmentally friendly has been recognised. In this paper the issues of electric lighting quality in educational buildings, focused on the analysis of lighting energy efficiency are presented. A brief characteristic of the selected educational building and requirements for the assessment were presented. The lighting conditions in selected interiors of the building and the lighting energy efficiency in the whole building were evaluated. To demonstrate the opportunity to improve lighting conditions and energy efficiency, four solutions for each selected interior were proposed. New fluorescent and LED lighting solutions were compared in detail. The comparison between the existing lighting and new solutions was conducted either. The lighting in evaluated building was not energy efficient and what worse, the lighting conditions in many interiors were much below the requirements. Introducing new lighting solutions should improve the quality of luminous environment in interiors and reduce substantially the lighting power installed as well as the energy use in the building.

Endoscope equipment is used in many applications. One of them is medical diagnostics. The illuminator is an important part of the endoscope, as it enables the performance of the observed object. The quality of light is particularly important if the assessed essential feature is the colour of an object or its distribution on the surface of the object. For this reason, special attention should be paid to the quality of the illuminator in terms of colour rendering, as well as adapting it to the intended diagnostic procedure. The use of light emitting diodes allows shaping flexibly the spectral characteristics which is an innovative solution in case of endoscope equipment. In the paper the idea of the endoscope illuminator construction, based on 13 LEDs, that allows adjusting the correlated colour temperature is presented. The essential part of the paper is the issue of quality of colour mixing. Results of exemplary simulations are presented and compared with the measurement results of performed mixing elements. They are evaluated from the point of view of obtained superficial uniformity of colour mixing on the output of the element.

Construction of endoscopes which are known for decades, in particular in small devices with the diameter of few millimetres, are based on the application of fibre optic imaging bundles or bundles of fibers in the illumination systems (usually with a halogen source). Cameras - CCD and CMOS – with the sensor size of less than 5 mm emerging commercially and high power LED solutions allow to design and construct modern endoscopes characterized by many innovative properties. These constructions offer higher resolution. They are also relatively cheaper especially in the context of the integration of the majority of the functions on a single chip. Mentioned features of the CMOS sensors reduce the cycle of introducing the newly developed instruments to the market. The paper includes a description of the concept of the endoscope with a miniature camera built on the basis of CMOS detector manufactured by Omni Vision. The set of LEDs located at the operator side works as the illuminating system. Fibre optic system and the lens of the camera are used in shaping the beam illuminating the observed tissue. Furthermore, to broaden the range of applications of the endoscope, the illuminator allows to control the spectral characteristics of emitted light. The paper presents the analysis of the basic parameters of the light-and-optical system of the endoscope. The possibility of adjusting the magnifications of the lens, the field of view of the camera and its spatial resolution is discussed. Special attention was drawn to the issues related to the selection of the light sources used for the illumination in terms of energy efficiency and the possibility of providing adjusting the colour of the emitted light in order to improve the quality of the image obtained by the camera.

Human eye is able to change its sensitivity to light in the process of adaptation. Still the process of vision can be accompanied by inconvenient phenomena, e.g. glare. The newest European norms recommended the CIE Unified Glare Rating method to estimate glare. A condition of practical realization of this method is the knowledge of the luminance distribution in the room. The best detection method is to use a CCD camera, which allows to evaluate all the quantities needed to calculate the UGR index: the background luminance, the luminance of the luminous parts of each luminaire at the observer's eye, the solid angle of the luminous parts of each luminaire and the position index for each luminaire. In the paper a definition of the background luminance Lb and the influence of the errors in Lb estimation on the value of the UGR index are presented. Two methods of the background luminance measurement are described and discussed.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

More and more CATV operators in Poland offer their subscribers a fast Internet access and other services. To offer high-speed Internet services cable operators create data networks that operate over hybrid fiber-coax (HFC) plant. In the paper a basic architecture of such network and data transmission standards are described.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the article the recommended by the CIE method of the discomfort glare evaluting is presented. A condition of practical realization of this method is the knowledge of luminance distribution in the room. The best detection method is using the CCD camera, which allows to evaluate all the quantities needed to calculate the UGR index: the background luminance, the luminance of the luminous parts of each luminaire at the observer's eye, the solid angle of the luminous parts of each luminaire at the observer's eye and the position index for each luminaire.