Search for dissertations about: "photochromic damage"

Found 3 swedish dissertations containing the words photochromic damage.

  1. 1. Properties of Volume Bragg Gratings and Nonlinear Crystals for Laser Engineering

    Author : Staffan Tjörnhammar; Fredrik Laurell; Valdas Pasiskevicius; Takunori Taira; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; volume Bragg grating; VBG; thermal effects; nonlinear optics; KTiOPO4; quasi-phase matching; photochromic damage; grey-tracking; color centers; blue-light induced infrared absorption; BLIIRA; Physics; Fysik;

    Abstract : This thesis focuses on two topics: thermal limitations of volume Bragg gratings (VBGs) employed as laser-cavity mirrors and formation of color centers in KTiOPO4 and its isomorphs.To explore the mechanisms of the thermal limitations of VBGs in high power lasers, I designed and constructed a diode-pumped, solid‑state laser with a VBG as cavity mirror that had a significantly higher absorption than what is typical. READ MORE

  2. 2. Characterization of domain switching and optical damage properties in ferroelectrics

    Author : Junji Hirohashi; Fredrik Laurell; Ady Arie; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; quasi-phase matching; ferroelectric domains; stoichiometric LiNbO3; stoichiometric LiTaO3; KTiOPO4; KNbO3; polarization switching; periodic electric field poling; optical damages; Optical physics; Optisk fysik;

    Abstract : Nonlinear optical frequency conversion is one of the most important key techniques in order to obtain lasers with wavelengths targeted for specific applications. In order to realize efficient and tailored lasers, the quasi-phase-matching (QPM) approach using periodically-poled ferroelectric crystals is getting increasingly important. READ MORE

  3. 3. Blue Laser Source for Laser-Induced Fluorescence

    Author : Jesper Holm; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Second Harmonic Generation; Lasers; PPKTP; ALA; Tapered laser diodes; External cavity lasers; Laser-induced fluorescence; photodynamic therapy; mTHPC;

    Abstract : Laser-induced fluorescence is a clinical diagnostic tool, used for tumor demarcation and detection. The technique relies on the injection or topical application of a light sensitive drug called a photosensitizer. This substance has the ability to be accumulated to higher concentrations in cancer cells than in normal cells. READ MORE