Sökning: "optical limiting"
Visar resultat 6 - 10 av 77 avhandlingar innehållade orden optical limiting.
6. Surface-normal multiple quantum well electroabsorption modulators : for optical signal processing and asymmetric free-space communication
Sammanfattning : Electroabsorption is the physical phenomenon by which the absorption of light in a medium can be controlled by applying an electric field. The Quantum–Confined Stark Effect, which makes the absorption band–edge in quantum wells very field–dependent, together with the strong absorption peak provided by excitons, are the physical foundations for the success of electroabsorption modulators based on quantum well structures in telecommunication networks. LÄS MER
7. Phase Noise Tolerant Modulation Formats and DSP Algorithms for Coherent Optical Systems
Sammanfattning : Coherent detection together with multilevel modulation formats has the potential to significantly increase the capacity of existing optical communication systems at no extra cost in signal bandwidth. However, these modulation formats are more susceptible to the impact of different noise sources and distortions as the distance between its constellation points in the complex plane reduces with the modulation index. LÄS MER
8. Dendron decorated chromophores for optical power limiting applications
Sammanfattning : The need for protection of eyes and electro-optic sensors from powerful lasers has increased the need for new and better optical power limiting (OPL) materials that can protect against laser light. In this study the synthesis and characterization of dendron-coated OPL chromophores (porphyrins, thiophenes, and platinum(II) acetylides) are discussed. LÄS MER
9. Organic and organometallic compounds for nonlinear absorption of light
Sammanfattning : The demand for protection of eyes and various types of optical sensors from laser-beam pulses has resulted in the search for optical limiting devices that have the property of being transparent at low intensity of light (normal light), but non-transparent towards high intensity (laser) light. This type of protection may be obtained by using an organic material that displays nonlinear optical (NLO) properties. LÄS MER
10. All-optical nonlinearity mitigation in fiber-optic communications
Sammanfattning : The two main factors limiting the data throughput in modern fiber-optic communication links are the noise added by amplifiers and the nonlinear response of the optical fiber due to the Kerr effect. Today there are communication systems operating remarkably close to the limits set by these two factors. LÄS MER