Sökning: "parabolic beams"

Hittade 3 avhandlingar innehållade orden parabolic beams.

1. 1. Nonlinear Dynamics of Coherent and Partially Coherent Optical Waves

   Författare :Tobias Hansson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; soliton interaction; Wigner transform; logarithmically saturable media; Nonlinear Schrödinger equation; parabolic beams; partial coherence; quasilinear diffusion; modulational instability;

   Sammanfattning : In optics an important nonlinear effect is manifested by the fact that the refractive index, in addition to its frequency dependence, also depends on the intensity of the light. Nonlinear effects are present within a wide range of optical applications e.g. the fast growing fields of fiber-optic communication and all-optical signal processing. LÄS MER

3. 2. Nonlinear Theory of Partially Coherent Optical Waves

   Författare :Tobias Hansson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; partial coherence; beam collapse; saturable logarithmic media; soliton interaction; dressing method; parabolic beams; Wigner transform; invariants; modulational instability;

   Sammanfattning : Nonlinear effects arise in optics as a consequence of the medium properties being modified by the presence of light. Of particular interest are situations where the effect of the nonlinearity can be described by an intensity dependent refractive index and the subsequent interplay with dispersion and diffraction. LÄS MER

4. 3. A multi-prism lens for hard X-Rays

   Författare :Björn Cederström; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; x-ray; optics; refractive; lens; mammography; synchrotron; Physics; Fysik;

   Sammanfattning : This thesis describes a new type of refractive lens for hardx-rays. It is shown that a linear array of prisms, slightlyinclined with respect to the optical axis, will form a linefocus at a certain distance from the lens. Hence, the namemulti-prism lens. LÄS MER