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Design of metasurfaces for advanced optical elements
Březina, Tomáš ; Kvapil, Michal (referee) ; Hrtoň, Martin (advisor)
Metasurfaces represent an intriguing class of materials with a wide range of promising applications, one of them being advanced planar optical elements for industrial production and imaging. The main goal of this thesis is to design such an optical element, namely a beam-shaper consisting of dielectric anostructures in HCTA (high constrast transmitarray) arrangement. The first part of this work introduces a simplified theoretical model of the optical response of building blocks that facilitates understanding of the basic functional mechanism behind the phase metasurfaces. To quantify the optical response of dielectric building blocks with enough precision, numerical FDTD simulations were employed. As a result, a database compatible with lithographic fabrication procedures was created. To find the phase distribution ensuring the desired beam-shaping function, two approaches were investigated and implemented: the semi-analytical method of geometric transformation and the iterative Gerchberg-Saxton algorithm. The final output of this work is then the distribution of building blocks within the metasurface that imprints into the impinging beam the previously calculated phase profile.
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Luminaires and Applications with Power LEDs
Vaňko, Adam ; Pavelka, Tomáš (referee) ; Baxant, Petr (advisor)
Progress in development of modern LEDs, their long lifetime and high luminous efficacy predetermine them for usage in lighting systems. This master's thesis examines possibilities of application of LEDs in luminaires, parameters of diodes and problems, which can appear in construction of luminaire with LED lighting source. In the practical part of this thesis a luminaire is designed, capable of illuminating traffic signs, vertical surfaces, billboards and fasades. By standards required parameters of a lighting system and adaptability of application must be considered in complex predesign. Simulations of lighting scene, created in special computer software, measurements of optical point’s parameters and construction of real luminaire model using high quality CREE LEDs, are included in analysis of the problem. Parameters of the luminaire were proved by measurements of product’s attributes at light laboratory. There are also some suggestions for improvement and further development of the product.
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Evaluation of optical components for LED
Dobiáš, Jiří ; Pavelka, Tomáš (referee) ; Škoda, Jan (advisor)
This thesis deals with an evaluation of optical components for LED, which is based on laboratory measurements of available LED samples and optical elements. The evaluation is done according to established standards and is focused on efficiency and adjustment of luminous flux (beam angle, luminous curve). Furthermore was made a study engaged in an optical element influence on LED color properties (color temperature, spectral characteristics). In conclusion there is an optical elements usage overview and recommended procedure for selecting appropriate combination of LED and optical element.
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Design of metasurfaces for advanced optical elements
Březina, Tomáš ; Kvapil, Michal (referee) ; Hrtoň, Martin (advisor)
Metasurfaces represent an intriguing class of materials with a wide range of promising applications, one of them being advanced planar optical elements for industrial production and imaging. The main goal of this thesis is to design such an optical element, namely a beam-shaper consisting of dielectric anostructures in HCTA (high constrast transmitarray) arrangement. The first part of this work introduces a simplified theoretical model of the optical response of building blocks that facilitates understanding of the basic functional mechanism behind the phase metasurfaces. To quantify the optical response of dielectric building blocks with enough precision, numerical FDTD simulations were employed. As a result, a database compatible with lithographic fabrication procedures was created. To find the phase distribution ensuring the desired beam-shaping function, two approaches were investigated and implemented: the semi-analytical method of geometric transformation and the iterative Gerchberg-Saxton algorithm. The final output of this work is then the distribution of building blocks within the metasurface that imprints into the impinging beam the previously calculated phase profile.
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Optical element for the conveyors 2G25 varA
Pintr, Pavel
The optical element 2G25 varA is designed according the specification ČSN EN 12966 class B6 for traffic marking. The front optical lens is freeform optics with polynomial coefficients. This element uses RGB LED for mixing white light.
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Optical element 2G20 6x8 mm
Pintr, Pavel
Optical element 2G20 6x8 mm is designed for a variable traffic marking. It assures the mixing of RGB diodes in white light and its direction in accordance with the specification ČSN EN 12966 class B6.
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Evaluation of optical components for LED
Dobiáš, Jiří ; Pavelka, Tomáš (referee) ; Škoda, Jan (advisor)
This thesis deals with an evaluation of optical components for LED, which is based on laboratory measurements of available LED samples and optical elements. The evaluation is done according to established standards and is focused on efficiency and adjustment of luminous flux (beam angle, luminous curve). Furthermore was made a study engaged in an optical element influence on LED color properties (color temperature, spectral characteristics). In conclusion there is an optical elements usage overview and recommended procedure for selecting appropriate combination of LED and optical element.
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Luminaires and Applications with Power LEDs
Vaňko, Adam ; Pavelka, Tomáš (referee) ; Baxant, Petr (advisor)
Progress in development of modern LEDs, their long lifetime and high luminous efficacy predetermine them for usage in lighting systems. This master's thesis examines possibilities of application of LEDs in luminaires, parameters of diodes and problems, which can appear in construction of luminaire with LED lighting source. In the practical part of this thesis a luminaire is designed, capable of illuminating traffic signs, vertical surfaces, billboards and fasades. By standards required parameters of a lighting system and adaptability of application must be considered in complex predesign. Simulations of lighting scene, created in special computer software, measurements of optical point’s parameters and construction of real luminaire model using high quality CREE LEDs, are included in analysis of the problem. Parameters of the luminaire were proved by measurements of product’s attributes at light laboratory. There are also some suggestions for improvement and further development of the product.
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