Sökning: "Diffraction grating"

Visar resultat 1 - 5 av 10 uppsatser innehållade orden Diffraction grating.

  1. 1. Analyzing Synthetic Spider Silk-based Diffraction Grids for the Sunshade Project

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Johanna D'Ciofalo Khodaverdian; Amira Karlsson; [2023]
    Nyckelord :Sunshade project; Diffraction grating; Artificial spider silk; Climate change; Geoengineering;

    Sammanfattning : To mitigate climate change a proposed space-based geoengineering solutionis to screen off solar irradiance by placing a membrane in between the Earthand the Sun. The feasibility of such a project largely depends on minimizingthe mass of the shading screen and as an extension to the Sunshade projectthis thesis investigated how such a low-mass membrane could be designed. LÄS MER

  3. 2. Ray-Tracing Modeling of Grating Lobe Level Reduction by Using a Dielectric Dome Antenna

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Lukas Jonasson; [2023]
    Nyckelord :Array antenna; Dielectric dome; Ray-Tracing; Grating lobe; Particle Swarm optimization; Gruppantenn; Dielektrisk kupol; Strålspårning; Gallerlob; Particle Swarm optimering;

    Sammanfattning : With the newly deployed fifth-generation telecommunications system and upcoming sixth-generation, high-gain antennas with hemispherical scanning capabilities are of high interest. Phased array antennas allow for fast scanning capabilities with electronic beam-steering. LÄS MER

  4. 3. Near-infrared optical frequency comb Vernier spectroscopy in air and in a flame

    Master-uppsats, Umeå universitet/Institutionen för fysik

    Författare :Maryam Fakhri; [2017]
    Nyckelord :;

    Sammanfattning : A Vernier spectrometer is built with a near-infrared mode-locked Er:doped fiber laser, a Fabry-Perot cavity with finesse of 1000, a diffraction grating and a photo detector. The optical cavity provides high sensitivity in absorption detection by enhancing the interaction length of the light with molecular species contained in the cavity. LÄS MER

  5. 4. Method for the Characterisationof Grating Based Holographic Paper

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad materialvetenskap

    Författare :Max Karlsson; [2016]
    Nyckelord :;

    Sammanfattning : Grating based holographic images and patterns are widely used in packaging to catch the eye of the consumer. The characteristic rainbow-like reflection of light from holographic papers can be used either by itself or with a print to create interesting contrasts and optical effects. LÄS MER

  7. 5. Setup for Micro Photo- and Electro-Luminescence of Optoelectronic Device Structures

    Master-uppsats, KTH/Skolan för informations- och kommunikationsteknik (ICT)

    Författare :Yuxuan Sun; [2015]
    Nyckelord :Photoluminescence; Photoluminescence setup; Electroluminescence; Optoelectronic device;

    Sammanfattning : Photoluminescence (PL) is an optical emission induced by photon absorption in a material where electrons are excited from the ground state to excited states, then relax to the lowest excited states and recombine radiatively. The PL emission provides vital information on bandgap energy, material purity and crystal quality. LÄS MER