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Luminescence sensors based on LED were prepared by modification of LED poly- carbonate surface and following binding of luminescence dyes on this surface. Two methods of modification were utilized. The first one was the oxidation of the surface yielding free carboxylic groups. Such modified LEDs were then covered by cationic cresyl violet dye. The second modification consisted of nitration and consequent reduction to free amino groups followed by binding of anionic sulforhodamine dye. The stability of emission and the stability of dye binding were studied. Then, the response of constructed sensors to toluene as analyte in gas and liquid phase was measured.

The diploma thesis deals with the combined use of SEM and SPM techniques using optical fiber, which is used to collect the cathodoluminescent signal in close proximity to the sample. The thesis also includes a research section, which lists description of CPEM technique, the techniques used to modify the optical fiber, theoretical introduction to cathodoluminescence and techniques used to measure it. The practical part discusses the obtained measurement results and the problems that occurred in the process of modification of the optical fiber, its use as an SPM probe and in the measurement of cathodoluminescence active materials.

Title: Experiments from geometrical optics for teaching at primary and secondary school Author: Ing. Filip Hložek Department: Department of Physics Education Supervisor: RNDr. Jitka Houfková, Ph.D., Department of Physics Education Abstract: This work is focused on experiments in geometric optics. There is a research of textbooks for primary and secondary schools, that deals with this topic of physics. Most of the work is dedicated to the proposed manuals for experiments for the excercise of geometric optics in Practical Course in School Experiments I. The manuals were tested with several groups of students at Practical Course. The test results are briefly summarized here, including several adjustments of the manuals that has risen from it. The work also deals with mirror telescopes, aberrations, and the production of models of two telescopes - Newtonian and Cassegrain printed on a 3D printer. The models are then used in two experiments for Practical Course. Keywords: experiments, geometrical optics, optical instruments

In the theoretical part of this thesis there is summarized the basic knowledge about the fungal leaf diseases of cereals, their harmfulness and technologies of precision agriculture. The practical part deals with the detection of cereal infestation with fungal leaf diseases using noninvasive optical methods. The research was conducted on winter wheat using methods based on spectral reflectance, infrared thermal imaging, chlorophyll fluorescence imaging, and blue-green fluorescence imaging. The tested diseases were powdery mildew (Blumeria graminis f. sp. tritici), wheat stripe rust (Puccinia striiformis), and wheat leaf rust (Puccinia recondita f.sp. tritici).). In the case of spectral reflectance, the best results were obtained for spectral indices ANMB650-725 and ZM generally. Overall, the best results for all methods were achieved in the detection of wheat leaf rust. A very good indicator of disease infestation was infrared thermal imaging, with a higher level of infection implying an increase in leaf temperature and a lower difference between leaf and air temperature. Reliability of detection by chlorophyll fluorescence imaging differs between individual diseases, with the best results being generally achieved for actual quantum yield PSII and the non-photochemical quenching. The most promising method for the future is the blue-green fluorescence imaging, which achieved very good results for both, the estimation of infection level and contrast between the infected and the healthy part of the leaf.

Master thesis is focused on creating graphical user interface for the sensorical system based on Phase-OTDR. Theoretical part describes optical fibers, explains the principle of Bragg gratings, their production and their use in sensors. Methods of optical fiber attenuation and phase OTDR measurement are also described. Other part is focused on LabVIEW programming software and utilization of sensorical system and its components. Practical part deals with the user interface itself, which consists of two tabs. The first tab is designed for evaluation and display of measured data. The second tab is used to control and set up system components. Both of these tabs are further subdivided into other subtabs. Regarding the conclusion, further development of the program and options of hardware replacement for improving this sensorical system in the future will be discussed.

This dissertation thesis deals with a long range free space optical links for communication over the distance of few tens of kilometers in the atmosphere. The problematic of the beam propagation and atmospheric effects influencing the beam and the quality of the communication protocol are discussed. The measuring link is also designed to study the parameters of the communication link work conditions. The measuring link consists of two heads. The transmitter head is designed to use two optical beams with laser diodes at the wavelength of the atmospheric windows 850 or 1550 nm and the overall power of hundredths of mW. The receiver head includes the Fressnel lens. For the detection of very weak signal, the avalanche photodiode is used. In the end of this work, due to the high power of the transmitting optical beam, the laser safety conditions are also discussed, including the deduced optical transmitters construction recommendations.

The main goal of this diploma thesis is to design of high-speed optical network. The first part deals with theoretical knowledge in the field of optical transmissions, especially principle of wavelength division multiplexing. Generally speaking, this part is dedicated to optical connections over long distances. It will concentrate on different types of wavelength division multiplexing, optical fiber amplifiers and other basic optical components. Then it discusses influence of negative effects acting on optical transmission and discusses how to reduce or suppress their influence. Subsequently, there is designed backbone network in the Czech Republic in OptiSystem 7.0 software and are verified some mentioned theoretical knowledge. One of chapters also presents results of measurements of real optical routes in our state. The second part of the diploma thesis moves its attention on that part of optical network, which provides data connectivity to end users, that means it is focused on optical access network. There are described the most common topologies, standards and components. Based on these findings, in the last chapter, there is worked out design of optical access network FTTH (more precisely FTTD) in the selected location. Afterwards, the design is transferred to the OptiSystem 7.0 software, where is verified its functionality.

The main subject of this diploma thesis is to make a proposal to improve the optical access network for the transmission of Triple play services. I would here to the reader clarify method of proposal of optical network. There are described the kinds of optical access networks with parameters, for which we must look by their construction. There are described the modern methods of construction optical network too. In the theoretical part are discussed used architecture of networks too. I met here known standards, which I compared for big importance by their choice. A reason of construction of optical network are services known like Triple play. These services together with their problems and parameters are here discussed too. At the end of theoretical part I listed here measuring method for getting negative attribute distorting the led signal. In practical part the locality witch use the optical signal as the source of information is ordered. These network use unfit connections and has less possibilities than usual and this is the reason, why is the network not able to supply Triple play in requested quality. At first the analysis of ordered network was needed. Situation was complicated by the fact, that it has been prohibited entrance to me. The structure of network and network parts was known and documented by me. I made the proposals to improve this network in practical part. By the first proposal remained original kind of access network FTTB, but used new parts with higher performance. By the second proposal I made the network FTTH, by which it was possible to use the last haul optical cables with treatment and using new elements. It was needed to create solution by flat units. The resulting proposals are here evaluated, compared and cost evaluated. For rejection of access to optical network I did not make measuring, so I made simulation for variant FTTH for getting some parameters negative acting transmission.

Diploma thesis focuses on a problematics of an optical networks in terms of an optical cables laying and a work with individual fibers. Thesis contains an basic physical properties which are used in a fiber optics. Methodology of correct working procedures used in fiber optics is discussed at the same time. Thesis also contains detailed documentation of realized optical connections including scheme of realized outdoor connection. 3D design of an rack case is also part of the thesis. Rack case provides an option to simulate plenty of different lengths of optical routes. Rack case is designed in 6U variant.