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Measurement of directional non-uniformity of the correlated color temperature of LED luminaires for road lighting
Růžička, Josef ; Škoda, Jan (referee) ; Motyčka, Martin (advisor)
This master's thesis deals with the topic of correlated color temperature measurements. There has been an increase in the demand for accurate correlated color temperature measurements due to regulations concerning reconstruction of the street lighting made by Department of Industry and Business. The main objective of this work is to determine which measuring devices and methods would make correlated color temperature measurements to be done in the most accurate and practical way. The evaluation is based on five laboratory measurements and two outdoor measurements. The main subject of these measurements is biodynamic LED lamp Tungsram SLBt. A verification of certain output data as well as simulating situations that would be too difficult to measure is made by an algorithm created in Matlab software. Final part of the thesis deals with the accuracy differences among various correlated color temperature measuring methods. It describes advantages and disadvantages of these methods and proposes ideas for consequent inquiry. This thesis finds its use in correlated color temperature measurement error and uncertainty discoveries that will have to be dealt with in the future. Also, theoretical part of the thesis may be used as lighting technics learning material.
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Analysis of luminance analyser LDA - LumiDISP application for correlated color temperature measurement
Vlček, Pavel ; Škoda, Jan (referee) ; Motyčka, Martin (advisor)
This master's thesis deals with the search of commercially available luminance analysers and cameras that use the measurement of correlated colour temperature. It also deals with calculations of correlated colour temperature according to various available methods. The luminance analyser LDA-LumiDISP is based on a DSLR camera. The principle of its operation and possible errors in capturing pictures are discussed here. The work deals with extensive testing of the LDA-LumiDISP luminance analyser, which is primarily intended for measuring luminance in the set scene, but can also be used to measure the correlated colour temperature. The device is being tested in terms of measuring the correlated colour temperature in laboratory and field conditions. The result of the master's thesis is the calculation of measurements uncertainty for certain light sources and the optimization of the measuring algorithm to reduce them.
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Use of Luminance Analyser for the Quantification of Artificial Light at Night
Novák, Filip ; Motyčka, Martin (referee) ; Baxant, Petr (advisor)
This diploma thesis deals with obtrusive light and its measurement, especially with the help of luminance analyzers. In particular, the necessary theoretical basis for the design of a measuring methodology for obtrusive light or veil brightness of the sky is laid here. This mainly includes the division of obtrusive light and its manifestations, a description of the effects of obtrusive light on the environment, selected organisms and the human body. Also described herein are the biological mechanisms of the human body that are affected by light as such. Attention is also paid to streetlights, its classification and methods of reducing obtrusive light, as well as methods of measuring brightness and brightness analyzers. Last but not least, the night sky is also measured using the LumiDISP luminance analyzer and subsequent data are evaluated using the proposed method.
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Measurement uncertainties in photometry
Motyčka, Martin ; Baxant, Petr (referee) ; Škoda, Jan (advisor)
This master's thesis is focused on problematic of measurent unceartainties in photometry. Theoretical part describes photometric measururing instruments, their uncearnities and limitations. In the second part of this thesis there is a mathematical description of calculating uncearnities in laboratory conditions. In practical part there are calculations of uncearnities for photometric instruments at light laboraty VUT Brno.
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Unconventional Methods of Measurement in Photometry
Škoda, Jan ; Sokanský, Karel (referee) ; Gašparovský,, Dionýz (referee) ; Baxant, Petr (advisor)
This thesis deals with an unconventional possibility of measuring photometric values and the work is based on analysis of luminance made by commercially available digital photo camera. In the first part is represent an overview of current methods for measuring the photometry. You also can see the basic photometric values and required instrumentation needed to measure them. The focus of the work is concentrated on the description of the problems associated with setting the correct luminance of digital photography. It describes the dependency and correction procedures for calculating fixed luminance ratios of the individual images. The last part of this thesis is devoted to the possible use in practice, especially in the analysis of luminance of objects, luminaires and light sources. It also deals with an alternative description of luminaire and light sources to replace the luminous intensity curve etc.
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Near-field photometry
Kutý, Tomáš ; Baxant, Petr (referee) ; Škoda, Jan (advisor)
This thesis is focused on the theoretical and practical introduction to the verification procedures used today for obtaining luminosity curves of lamps. The introduction acquaints readers with the photometric variables. Consequently, it is theoretically described procedure for constructing luminance curves by zonal flow and further familiarization with the near-field photometry. For the practical part was chosen several lights. These lamps were measured by luxmeter first from a very close photometric distance from lights, and then from large distance. The next step was to obtain pictures of luminaries in planes C 0 to 345 ° (with a step of 15 °) of the angle gamma from 0 to 180 ° (in steps of 5 °). The measured data were processed by zonal flow and through programs LumiDISP and Matlab. The partial result of this thesis is to verify whether it is possible to use the luminance analyzer for obtaining luminosity curves, it means, if the luminosity curve obtained through luminance analyzer will comply with the curves obtained through a luxmeter. Further work should ascertain the feasibility of acquired photographs lamps from a very close photometric distance could create luminosity curve for any location and distance from the observer to measured lamps.
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Evaluation glare of indoor and outdoor lighting systems
Rotrekl, Matěj ; Baxant, Petr (referee) ; Škoda, Jan (advisor)
Recent years have seen an increasing focus on electric energy consumption as well as ecology in relation to human health. It is crucial to maintain the so called lighting comfort which is influenced by a wide range of lighting parameters, including illuminance, brightness, balance of illuminance, and glare. Thanks to all these parameters we can design lighting systems in such a way as to prevent energy waste and far too rapid deterioration of eyesight. This study therefore focuses on glare evaluation of indoor and outdoor lighting systems. In order to comprehend the issue thoroughly, a detailed description of human eyes and their functions is provided, followed by definitions of glare and types of glare. An overview of different calculations for indoor and outdoor glare is provided, considering the evaluation of daylight glare in terms of complex lighting systems. The study mentions several options involving unconventional methods for measuring glare (brightness). In the analytical part of the study, outdoor glare on Kolejní Street and indoor glare at the Prof. Brauner Hall at VUT measurements were obtained using brightness analyzer (an unconventional method). The thesis is concluded with a comparison of the conventionally and unconventionally obtained measurements, considering their respective advantages.
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Luminance scanning of luminaires and light sources
Ševčík, Ondřej ; Baxant, Petr (referee) ; Škoda, Jan (advisor)
Práce se zabývá měřením křivek svítivosti světelných zdrojů a svítidel konvenčními a nekonvenčními metodami. Úvodní část práce je věnována popisu zrakového systému a základních fotometrických veličin. Hlavní teoretická část je zaměřena na popis současných metod měření křivek svítivosti a nových metod měření pomocí jasového analyzátoru. Současně jsou pro jednotlivé metody uvedeny zdroje nejistot, které ovlivňují výsledky měření. Těžiště práce spočívá v návrhu metodiky měření křivek svítivosti z jasových skenů svítidla a následném ověření tohoto postupu vlastním měřením. Dále bylo provedeno srovnání naměřených výsledků navrženým postupem, s výsledky konvenčního měření na goniofotometru s luxmetrem.
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Comparison of Conventional and New methods of Measurement and Evaluation of Luminance
Svoboda, Miloslav ; Novák,, Tomáš (referee) ; Baxant, Petr (advisor)
Because luminance is the only value to which our sight responds, its measurement becomes important in terms of ensuring the proper function of vision. Nowadays luminance measuring can be made by conventional methods, such as direct using of luminance meter. However an entirely new method of measuring luminance levels is coming. This method is based on using luminance analyzers which work using a digital photography for the analysis of luminance. This thesis deals with these issues and is divided into several chapters, which form the two main parts of the thesis, the theoretical and the practical one. The theoretical part of the thesis deals with the basics of lighting technology, as well as the principles of measuring the luminance using conventional methods. New methods of measurement, i.e. using luminance analyzers, are discussed in two chapters which analyse both the principle and characteristics of analyzers available today. In the practical part is a comparative measurement carried out – in the laboratory and in terrain – using both methods.
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Evaluation of Lighting Quality Using Modern Software Tools
Fazekas, Tibor ; Škoda, Jan (referee) ; Baxant, Petr (advisor)
This thesis deals with the evaluation of the quality of lighting with the usage of the latest software products used nowadays. The first part of the work is about indoor lighting, the basic requirements invested in lighting, and the basic concepts of indoor lighting. The second part includes complete search for today's computer implements for projecting, simulating, calculation and analysis of light, their functions and characteristics, including luminance analyzers based on CCD sensors and their software equipment. The last part of the work has the task to model a computer room using softwares which can be found within the territory of VUT Brno, and the task was to assess its lighting. Following this, with the help of luminance analyzer, the task is to capture the scene under different lighting conditions and to evaluate the measured data.
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