Sökning: "Adaptive optics"

Visar resultat 16 - 20 av 25 avhandlingar innehållade orden Adaptive optics.

1. 16. Fast Adaptive Numerical Methods for High Frequency Waves and Interface Tracking

   Författare :Jelena Popovic; Olof Runborg; Hongkai Zhao; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high frequency waves; Helmholtz equation; interface tracking; time-space adaptivity; multiresolution; Hamilton-Jacobi;

   Sammanfattning : The main focus of this thesis is on fast numerical methods, where adaptivity is an important mechanism to lowering the methods' complexity. The application of the methods are in the areas of wireless communication, antenna design, radar signature computation, noise prediction, medical ultrasonography, crystal growth, flame propagation, wave propagation, seismology, geometrical optics and image processing. LÄS MER

3. 17. Study of a Large Deformable Mirror Concept

   Författare :Rikard Heimsten; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Large deformable mirror - Adaptive optics - Distributed Control - Local control: actuator family - Faceplate: vibration modes - Faceplate: Dimensionless modal analysis;

   Sammanfattning : It is attractive to integrate a large deformable mirror for adaptive optics into an astronomical telescope rather than using relay optics within an auxiliary instrument. However, the resulting large deformable mirror can be expensive, particularly for extremely large telescopes. LÄS MER

4. 18. Improving Peripheral Vision Through Optical Correction and Stimulus Motion

   Författare :Peter Lewis; Peter Unsbo; Linda Lundström; Jörgen Gustafsson; Michael Crossland; Linnéuniversitetet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; absolute central scotoma; central visual field loss; eccentric viewing; preferred retinal locus; open-view aberrometer; off-axis refractive errors; eccentric correction; dynamic visual acuity; spatial contrast sensitivity; temporal contrast sensitivity; spatio-temporal contrast sensitivity; Optometry; Optometri; Biomedical Sciences; Biomedicinsk vetenskap;

   Sammanfattning : The loss of central vision subsequent to macular disease is often extremely debilitating. People with central field loss (CFL) must use other peripheral areas of the retina in order to see; areas with inferior resolution capacity, which are also affected by off-axis optical errors. LÄS MER

5. 19. Wafer-level 3-D CMOS Integration of Very-large-scale Silicon Micromirror Arrays and Room-temperature Wafer-level Packaging

   Författare :Martin Lapisa; Frank Niklaus; Olav Solgaard; KTH; []
   Nyckelord :;

   Sammanfattning : This thesis describes the development of wafer-level fabrication and packaging methods for micro-electromechanical (MEMS) devices, based on wafer-bonding.The first part of the thesis is addressing the development of a wafer-level technology that allows the use of high performance materials, such as monocrystalline silicon, for MEMS devices that are closely integrated on top of sensitive integrated circuits substrates. LÄS MER

7. 20. Gradient Methods for Large-Scale and Distributed Linear Quadratic Control

   Författare :Karl Mårtensson; Institutionen för reglerteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large-Scale Control; Distributed Control; Linear Quadratic Gaussian Control; Gradient method; Controller Synthesis;

   Sammanfattning : This thesis considers methods for synthesis of linear quadratic controllers for large-scale, interconnected systems. Conventional methods that solve the linear quadratic control problem are only applicable to systems with moderate size, due to the rapid increase in both computational time and memory requirements as the system size increases. LÄS MER