Sökning: "optical filters"
Visar resultat 1 - 5 av 54 avhandlingar innehållade orden optical filters.
1. Generation and Applications of Picosecond Pulses in High-Capacity Fiber Optic Systems
Sammanfattning : This thesis deals with short optical pulse generation from actively mode-locked Erbium-doped fiber ring lasers (ML-EFRL) and their applications in all-optical signal processing (optical sampling and switching) and transmission experiments for high-capacity fiber optic systems. In future ultra-high bit-rate optical time division multiplexed (OTDM) systems, one of the key requirements is to develop reliable optical pulse sources that can generate high quality optical pulses. LÄS MER
2. Material and technique development for ultrasound optical tomography using spectral hole burning filters
Sammanfattning : The molecular sensitivity provided by optical photons has potential advantages in medical diagnostics, for example, in distinguishing healthy from cancerous tissue. However, scattering resulting from inhomogeneities in the refractive index of tissues prevents spatially resolved optical measurements in biological material, except at very shallow depths. LÄS MER
3. Generation and Transmission of Optical Solitons at Ultrahigh Bit Rates
Sammanfattning : This thesis deals with the generation and transmission of optical solitons in ultrahigh-speed fiber-optic communication systems. For optical soliton pulses the fiber dispersion and nonlinearity can under certain circumstances cancel each other, thus allowing the solitons to remain undistorted over long distances. LÄS MER
4. Nanostructured Semiconductor Materials for Light Manipulation Functions
Sammanfattning : Structuring of semiconductor materials is utilized in many optoelectronic devices, e.g, in order to make them more efficient, cost-effective, and/or to obtain specific wavelength-engineered responses. Semiconductor materials are widely used in optoelectronic devices due to their favorable optical and electric properties. LÄS MER
5. Development of Models, Methods, and Materiel for Deep Tissue Imaging using Light, Ultrasound, and Spectral-Hole Burning
Sammanfattning : The medical imaging technique called “ultrasound optical tomography” (UOT) entails light scattered in tissue that is given spatial information by interacting with an ultrasound field, thus allowing for molecular information to be imaged with ultrasonic resolution. This thesis discusses how UOT can be implemented, with most attention put toward the implementation using spectral-hole-burning filters (SHF) in rare-earth-ion-doped crystals. LÄS MER