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Announcements 2/15/12. Prayer Exams: I just got them from Testing Center 1 hour ago. Will work on grading with TAs… target time = graded by Friday evening. Exam solutions: posted to website.
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Announcements 2/15/12 • Prayer • Exams: I just got them from Testing Center 1 hour ago. Will work on grading with TAs… target time = graded by Friday evening. • Exam solutions: posted to website. • If you have questions about your exam after getting it back, please look at the solutions first. If you can’t figure things out from there, then come to me or the TAs. • Reading assignment change. For next time: • Remove section 6.7 (we’ll talk about that section today) • Add Appendix 6.A • Add section 7.1
Reading Quiz • When multiple elements are in a beam path, the Jones matrices to find the final optical polarization are written • with the first element’s matrix on the right • with the first element’s matrix on the left • in any order
Reading Quiz • After passing through a set of polarization elements, the intensity of the outgoing light can become reduced relative to the intensity of the incident light. • true • false
Review question (ungraded) • In polaroid films, polymer chains are aligned. The polarization axis that transmits light is oriented: • along the chains • perpendicular to the chains • at 45 degrees to the planes
Jones matrices: review from last time • Matrices for linear polarizers: • x-polarization • y-polarization • 45 polarization • arbitrary angle polarization
Thought question (ungraded) • The element that should be used to change linearly polarized light into circularly polarized light is the • quarter waveplate • half waveplate • full waveplate (“Waveplate” is synonymous with “optical retarder”. Through anisotropic crystal effects it introduces a phase shift, or retardance, between horizontally and vertically polarized light.)
Waveplate = Retarder = Birefringent Crystal • Jones matrices for quarter and half waveplates
Thought question (ungraded) • If a RCP beam strikes a metal mirror at normal incidence, what will the resulting beam be? • LCP • RCP • linearly polarized • unpolarized
Thought question (ungraded) • A laser beam traveling 2 inches above the surface of an optical table reflects off a mirror and remains parallel to the plane of the table. Top view is shown. Which polarization is in the x-direction and which is in the y-direction? (x-direction = horizontal, y = vertical) • s-polar = x, p-polar = y • s-polar = y, p-polar = x
Final Jones matrices • Reflection • Transmission