Sökning: "diffraction grating"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden diffraction grating.

  1. 1. Electromagnetic simulation and design of etched diffraction grating demultiplexers

    Författare :Jun Song; Sailing He; Dries Van Thourhout; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; etched diffraction grating; wavelength division multiplexing; passive devices; diffraction grating; planar waveguide devices; DWDM; optical communication.; Photonics; Fotonik;

    Sammanfattning : Among various planar lightwave circuits for multiplexing/demultiplexing in an optical communication system, etched diffraction gratings (EDGs) have shown great potential due to their compactness and high spectral finesse. Conventional numerical methods for grating simulation cannot be used to simulate an EDG demultiplexer of large size (in terms of the wavelength). LÄS MER

  3. 2. High efficiency grating-coupled surface-emitting semiconductor lasers

    Författare :Niklas Eriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; diffraction grating; chemically assisted ion beam etching; blazed grating; integrated optics; multilayer substrate reflector; semiconductor laser; grating-coupled surface-emitting laser; electron-beam lithography; waveguide grating coupler; nenofabrication;

    Sammanfattning : .... LÄS MER

  4. 3. 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

  5. 4. Grating Based Lasers for Photonic Integration and Surface Emission

    Författare :Peter Modh; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; integrated optics; surface-emitting lasers; laser resonators; optical planar waveguide couplers; unstable-resonator lasers; semiconductor lasers;

    Sammanfattning : This thesis deals with the fabrication and characterization of grating-based integration-compatible semiconductor lasers. Waveguide gratings provide feedback for the laser resonators, and are used to diffract the laser output out of the waveguide for surface-emission. LÄS MER

  7. 5. Application and Design Developments in Diffractive Optics

    Författare :Mathias Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; analog-to-digital converter; free-space optical interconnect; beam shaper; robust fan-out; multichannel rotary joint; diffractive optics; DOE; subwavelength grating; spatial light modulator SLM ;

    Sammanfattning : There has been strong development in the field of diffractive optics (DO) in research laboratories over the past two decades. Much progress has been made, both in design and analysis, as well as in manufacturing techniques. However, so far DO have only reached the market in small numbers. LÄS MER