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Pupil Mapping (aka PIAA) Robert J. Vanderbei 2007 March 16 What DO We Know Today TPF-Lite Meeting Princeton University http://www.princeton.edu/∼rvdb Pupil Mapping—Summary • Create a nonuniform amplitude profile using a pair of mirrors • Diffraction limits contrast to 10−5 • Pre- and post-apodizers restore desired contrast at expense of throughput and achromaticity • High throughput and small iwa • Sensitive to low-order aberrations • Difficult to manufacture The Pupil-Mapping Concept 2 Z Ra r r 1.5 z 1 hr 0.5 0 r a a Rr −0.5 −0.5 0 0.5 a h a r bottom. 0 4 10 3.5 10 3 10 −2 −4 Intensity Relative to Peak Output Amplitude Relative to Input High-Contrast Amplitude Profile 2.5 2 1.5 −6 10 −8 10 −10 10 −12 1 10 0.5 10 0 −0.5 −14 −16 0 Pupil−Plane Radius in fraction of Aperture 10 0.5 −60 −40 −20 0 20 Image−Plane Radius in L/D radians Full Pupil-Mapping System 40 60 Fig. 2.— Left. An amplitude profile providing contrast of 10−10 at tight inner working angles. Right. The corresponding on-axis point spread function. Post-apodize here Pre-apodize here Occulter f Pupil Mapper f Reverse Pupil Mapper – 21 – Diffraction Analysis of Apodized Pupil-Mapping −5 2nd Pupil Amplitude Map 6 Target apodization Pre−apodizer Post−apodizer Achieved apodization 3 2.5 2 1.5 1 0 0.002 0.004 0.006 0.008 Radius (m) 0.01 First surface Second surface 4 3 2 0 0.012 0 2nd Pupil Phase Map 0.01 0.012 0 Intensity relative to peak Phase Phase smoothed 0.15 Phase in radians 0.002 0.004 0.006 0.008 Radius (m) PSFs 0.2 0.1 0.05 0 −0.05 Lens/Mirror profiles 1 0.5 0 x 10 5 Lens/Mirror height (m) Output Amplitude Relative to Input 3.5 0 0.002 0.004 0.006 0.008 Radius (m) 0.01 0.012 ideal PSF achieved @ 632nm achieved @ 442nm achieved @ 822nm −5 −10 −15 −20 0 5 10 working angle in units of λ/D 15 On-Axis PSF at 1st and 2nd Focus 0 first focus (same as ideal PSF) second focus, no occulter second focus, with occultor −2 −4 Log10 Intensity −6 −8 −10 −12 −14 −16 −18 0 2 4 6 8 10 12 working angle in units of λ/D 14 16 18 Off-Axis PSFs tilt = 0.0009 λ/D 0.0144 λ/D 0.1155 λ/D 1 λ/D 2 λ/D 3 λ/D 4 λ/D 5 λ/D 0 1st FOCUS −1 −2 −3 −4 nd 2 FOCUS −5 −6 −7 SHAPED PUPIL −8 −9 −10 Fig. 6.— Simulated responses due to off-axis sources in apodized pupil mapping and concentric rings. First row: pupil mapping, first focus, after the occulter. Second row: pupil mapping, second focus (note the expected mirror flip). Third row: concentric ring coronagraph. The columns in this figure represent different off-axis source angles, labeled on the Cross-Sectional Plot Log 10 of Intensity relative to response with no obstruction 0 Tilt of 4 λ/D 2 λ/D 1 λ/D −0.5 −1 −1.5 −2 −2.5 −3 −3.5 −4 0 1 2 3 4 5 6 7 working angle in units of λ/D 8 9 10 Throughput vs. Angle 1 Pupil mapping Concentric ring shaped pupil 0.9 Total power throughput 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 1 2 3 working angle in units of λ/D 4 5 Sensitivity to Zernikes Pupil Mapping −4 (0,0) (1,1) (2,0) −5 −6 (2,2) (3,1) (3,3) −7 −8 −9 (4,0) (4,2) (4,4) −10 −11 −12 Sensitivity to Zernikes Concentric Rings −4 (0,0) (1,1) (2,0) −5 −6 (2,2) (3,1) (3,3) −7 −8 −9 (4,0) (4,2) (4,4) −10 −11 −12 Sensitivity to Zernikes Radial Profiles (1,1) (0,0) (2,0) 0 Ideal Apodization with no aberrations Concentric Rings Pupil Mapping (2nd focus) −2 −4 −6 −8 −10 −12 (2,2) (3,1) (3,3) (4,0) (4,2) (4,4) Log10 of contrast 0 −2 −4 −6 −8 −10 −12 0 −2 −4 −6 −8 −10 −12 0 5 10 0 5 working angle in units of λ/D 10 0 5 10 Shaklan Plots (1,1) (2,0) −5 Concentric rings, 4λ/D Concentric rings, 8λ/D Pupil mapping, 2λ/D Pupil mapping, 4λ/D Pupil mapping, 8λ/D −5 10 10 −10 −10 10 10 −4 10 (2,2) −2 10 0 −4 10 10 (3,1) −5 0 10 (3,3) −5 −5 10 10 Contrast 10 −2 10 −10 −10 10 −10 10 −4 10 −2 10 0 10 −4 10 10 −2 10 0 −5 −10 10 −10 −10 10 −2 10 0 10 0 10 −5 10 10 −2 10 (4,4) −5 10 −4 10 (4,2) (4,0) 10 −4 10 10 −4 −2 0 10 10 10 RMS of aberration in units of wave −4 10 −2 10 0 10 Pupil Mapping Lab (Subaru Telescope) Panels provide thermal, optical and acoustic isolation M1 Flat mirror M2 Light source: He-Ne laser + SM fiber CCD PIAA unit #1 Binary mask is here PIAA unit #2 Lens DM Wavefront control and a classical apodizer (binary mask) have been included in the experiment.. Guyon’s Lab Results Contrast ≈ 6 × 10−4