1. Physics 681: Solar Physics and Instrumentation – Lecture 8 Carsten Denker NJIT Physics Department Center for Solar–Terrestrial Research

2. September 27, 2005Center for Solar-Terrestrial Research Spectroscopy  Grating Spectrograph  Lyot Filter  Fabry-Pérot Interferometer  Please check your TurnItIn.com account!

3. September 27, 2005Center for Solar-Terrestrial Research Grating Spectrograph  Collimate light beam on spectrograph slit  Focal ratio of collimator  Grating equation  Angular dispersion  Linear dispersion http://outreach.atnf.csiro.au/education/senior/astrophysics/spectrographs.html

4. September 27, 2005Center for Solar-Terrestrial Research

5. September 27, 2005Center for Solar-Terrestrial Research Lyot Filter  Birefringent filter  Alternating sequence of polarizers and birefringent crystals  Polarizers are mounted parallel to each other  Uniaxial crystals cut parallel to their optical axis  Optical axis of crystals and polarizers make a 45º angle  Thickness of the nth crystal plate  Phase difference and birefringence  Interference of two waves passing a single element

6. September 27, 2005Center for Solar-Terrestrial Research  Intensity  Transmission maxima  Separation  N elements between N + 1 polarizers  Individual transmission maxima at  Central wavelength

7. September 27, 2005Center for Solar-Terrestrial Research NIR Lyot-Filter Design ½ Wave PlateLC Crystal Polarizer Calcite Plates

8. September 27, 2005Center for Solar-Terrestrial Research  Band width  Birefringence (calcite J = –0.172 and quartz J = 0.0092)

9. September 27, 2005Center for Solar-Terrestrial Research Fabry-Pérot Interferometer  Phase difference  Outgoing wave  Intensity

10. September 27, 2005Center for Solar-Terrestrial Research  Band width  Finesse http://www.physicsdaily.com/physics/Fabry-Perot

11. September 27, 2005Center for Solar-Terrestrial Research Coating Curves

12. September 27, 2005Center for Solar-Terrestrial Research Filter Transmission and Spectrum