Sumários
BIRREFRINGENCE
8 Outubro 2019, 09:00 • José Manuel Rebordão
The symmetries of the calcite and why dipoles should have different properties as a function of the polarization of the EM wave, in the context of the Lorentz model.
Electrical permittivity tensor as a symmetrical tensor if the Poynting vector retains its use to determine the direction and irradiance of the flow of energy of an EM wave. Symmetric tensors, quadratic forms, real eigenvalues and principal directions Impermeability tensor. Ellipsoid of the Indexes (EI).
How to use the EI to determine the polarization modes and their velocities in an anisotropic medium. Explanation of the value of the EI from Maxwell equations.
Uniaxial materials. Ordinary and extraordinary indexes. Particular cases: waves propagating along or perpendicularly to the optical axis.
Wave plates. Fast and slow axis. Half-wave plates and quarter-wave plates. Rotation of linear polarization and transformation between linear and circular polarization.
Example: How birefringence can be used in CD readers to ensure that the illumination and detection geometries are at 0 degrees.
A brief introduction to the electrooptic effect.
Presentation by Luís Neves: High performance organic photovoltaic cells for indoor use.
NEXT CLASS
Electrooptic effect and applications.
BIBLIOGRAPHY
Saleh, Fundamentals of Photonics, Ch. 6.
Fotodiodos - parte 2
7 Outubro 2019, 15:00 • David de Castro Alves
Explanação, montagem e teste do amplificar de trans-impedância para à realização de medidas ópticas com os fotodiodos.
Fotodíodos - Parte 3
7 Outubro 2019, 14:00 • David de Castro Alves
Explanação, montagem e teste do amplificar de trans-impedância para à realização de medidas ópticas com os fotodiodos.
POLARIZATION PHENOMENA
1 Outubro 2019, 09:00 • José Manuel Rebordão
Fresnel equations: fundamental basis, from the Maxwell boundary conditions; plane of incidence and plane of polarization; Fresnel equations; amplitude and dephasing issues in reflection and transmission; Brewster and internal reflection angles; reflectance and transmittance; normal incidence.
Polarization: model of polarization based on two orthogonal components; polarization ellipse; special cases of linear, elliptical, circular polarization; case of non-polarized light. Representation of polarization in terms of Poincaré sphere, Stokes parameters; brief mention to Mueller and Jones matrices. Concept of “polarizer and “Analyser”. Malus Law for linear polarizers.
Generation of polarization by dichroism, reflection and scattering.
Photonics strategy roadmaps: presentation by the three students on the contributions of Photonics for Zero-Emissions, Less Waste (Luís Neves), Live Longer, Feel Better (Andreia Domingos) and Feed the World (Francisco Costa) – main source: “Europe’s Age of Light – How Photonics will power growth and innovation”, by Photonics-21.
“Europe’s Age of Light – How Photonics will power growth and innovation”, by Photonics-21: Zero-Emissions, Less Waste
“Europe’s Age of Light – How Photonics will power growth and innovation”, by Photonics-21: Live Longer, Feel Better
“Europe’s Age of Light – How Photonics will power growth and innovation”, by Photonics-21: Feed the World
NEXT CLASS
Birrefringence. Optics of non-isotropic materials.
BIBLIOGRAPHY
Saleh, Fundamentals of Photonics, Ch. 6.
Hecht, Optics, Chapter 4.6, 4.7 (Fresnel equations)