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Optical Vortex Coronagraph - Higher Order Concerns -. Grover Swartzlander College of Optical Sciences University of Arizona Tucson, Arizona Funding: U. S. Army Research Office, JSOP, and the State of Arizona. Prepared for JPL Coronagraph Review, 29Sept06. Current Research Group.
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Optical Vortex Coronagraph- Higher Order Concerns - Grover Swartzlander College of Optical Sciences University of Arizona Tucson, Arizona Funding: U. S. Army Research Office, JSOP, and the State of Arizona Prepared for JPL Coronagraph Review, 29Sept06
Current Research Group Joshua Erin Jennifer Rukiah Raul Kim Ford Harwell Abdul-Malik Hernandez Missing: Carmen Paleta-Toxqui Radek Celechovsky Mary Anne Peters
Non-Achromatic Vortex Lens Dd Dd Pitch Multiplicity: m=1 m= 2 Glass Vortex Lenses of different pitch multiplicity Screw Pitch (Dd) m waves of phase retardation
Circulating Momentum Helical Wavefront Transverse k-Vectors
Vortex Intensity Profile Vortex Core: black at a SINGLE POINT owing to total destructive interference
Vortex mask Imaging system AS LS L1 L2 L3 L4 Camera Optical fiber d f3 f2 f3 z f1 Optical Vortex Coronagraph Optical Vortex Coronagraph, (Ret.) Lt. Col. G. Foo. D. Palacios, G. Swartzlander, Opt. Lett (2005)
Vortex mask Imaging system AS LS L1 L2 L3 L4 Lyot Stop Camera Optical fiber d f3 f2 f3 z f1 Optical Vortex CoronagraphExit Pupil
Vortex mask Imaging system AS LS L1 L2 L3 L4 Camera Optical fiber d f3 f2 f3 z f1 Optical Vortex Coronagraph- Experimental -
Vortex mask Imaging system AS LS L1 L2 L3 L4 Camera Optical fiber Lyot Stop d f3 f2 f3 z f1 Optical Vortex CoronagraphStar (green) -- Planet (red)
WITHOUT Vortex Lens Vortex mask Imaging system AS LS L1 L2 L3 L4 Camera Optical fiber WITH Vortex Lens d f3 f2 f3 z f1 Images
Fabrication - Finite Steps -
Achromatic Vortex Lens G. Swartzlander, Opt. Lett. 2006
Other Approaches to Achromatization • Large values of m • Achromatize only C0 mode • Air-Gap Achromats • Subwavelength Gratings • Blazed Superwavelength Grating
Next Experiment Piezo 1kHz Tip/Tilt Mirror (in collaboration with Laird Close and Mary Anne Peters) Imaging Lens 8” f/8.8 Telescope with ~ 5 cm Stop (> f/36) 10 cm Achromatic Doublet with 2mm Stop Fast Camera Beam Splitter Long Exposure Camera Lyot Stop Specs: l=850 nm Strehl: 0.95 Target: Sirius B Exposure: 2 min Mirror Vortex Lens Lens Lens Imaging Lens
What needs to be done • Fabricate high resolution masks • Identify materials/configurations for achromats • Experiments with high precision optics • Combine with adaptive optics systems • Optimization numerical studies • Numerical testbed for non-ideal conditions
Imaging system AS Mask LS L1 L2 L3 L4 Camera Optical fiber DAS DLS d f3 f2 f3 z f1