Sökning: "Grating"

Visar resultat 21 - 25 av 115 avhandlingar innehållade ordet Grating.

  1. 21. Diffractive Optics Design

    Författare :Jörgen Bengtsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; computer-generated waveguide hologram; diffractive optics; fan-out; millimeter wave radiation; proximity effect; optimal-rotation-angle method; kinoform; integrated optics; beam shaping; outcoupling grating; scalar optics;

    Sammanfattning : Diffractive optical elements (kinoforms) change the way light propagates, and can perform very complex tasks. They can split an incident beam into any number of outgoing, and possibly focused, beams (fan-out). LÄS MER

  2. 22. Optical properties and helicity in liquid crystals

    Författare :Anders Dahlgren; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; de Vries formula; smectic A*; smectic helix; Poincaré sphere; homeotropic alignment; chiral; light switch; birefringence; electroclinic; diffraction method; indicatrix; phase grating; helial pitch; snisotropy; liquid crystals; smectic C*; handedness; book-shelf geometry; Cano method; ferroelectric; biaxiality; dielectric tensor;

    Sammanfattning : .... LÄS MER

  3. 23. Tandem optical parametric oscillators using volume Bragg grating spectral control

    Författare :Markus Henriksson; Fredrik Laurell; Hiromasa Ito; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optical parametric oscillators; mid-infrared; volume Bragg gratings; PPKTP; ZGP; nonlinear optics; narrowband OPO; Physics; Fysik;

    Sammanfattning : This thesis describes research on near degenerate quasi phase-matched opticalparametric oscillators (OPO) where volume Bragg gratings (VBG) are used toproduce narrow oscillation bandwidth. These OPOs are then used to pump a secondOPO to generate mid-infrared radiation. The atmospheric transmission windows in the 3. LÄS MER

  4. 24. Dynamic and Static Diffractive Optics - some Examples

    Författare :Björn Löfving; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subwavelength grating; spatial light modulator; phase retrieval; diffractive optics; ferroelectric liquid crystal; analog-to-digital conversion; optical switch; feedback generated hologram;

    Sammanfattning : Diffractive optics is a modern branch of optics, that exploits microstructures to manipulate the propagation of light. Fast computers and the progress in manufacturing technique of microelectronics have made possible a rapid development of diffractive optics during the past 10 years. LÄS MER

  5. 25. Grating-Coupled Surface-Emitters --- Highly Directional Outcouplers and Spatially Coherent Lasers

    Författare :Niklas Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis deals with grating-coupled surface-emitting semiconductor lasers. The work is part of a larger effort that aims at developing semiconductor lasers with built-in beam-forming elements, which eliminate the need for external micro-optics. LÄS MER