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Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 13, Iss. 7 — Apr. 4, 2005
  • pp: 2394–2402

10-7 contrast ratio at 4.5λ/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks

Abhijit Chakraborty, Laird A. Thompson, and Michael Rogosky  »View Author Affiliations

Optics Express, Vol. 13, Issue 7, pp. 2394-2402 (2005)

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We present here new experimental results on high contrast imaging of 10-7 at 4.5λ/D (λ=0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5λ/D diameter and a multi-Gaussian pupil plane mask. Both the masks were fabricated on very high surface quality (λ/30) BK7 optical substrates using nano-fabrication techniques of photolithography and metal lift-off. This process ensured that the shaped masks have a useable edge roughness better than λ/4 (rms error better than 0.2 microns), a specification that is necessary to realize the predicted theoretical limits of any mask design. Though a theoretical model predicts a contrast level of 10-12, the background noise of the observed images was speckle dominated which reduced the contrast level to 4×10-7 at 4.5λ/D. The optical setup was built on the University of Illinois Seeing Improvement System (UnISIS) optics table which is at the Coude focus of the 2.5-m telescope of the Mt. Wilson Observatory. We used a 0.820 micron laser source coupled with a 5 micron single-mode fiber to simulate an artificial star on the optical test bench of UnISIS.

© 2005 Optical Society of America

OCIS Codes
(010.1080) Atmospheric and oceanic optics : Active or adaptive optics
(050.1220) Diffraction and gratings : Apertures

ToC Category:
Research Papers

Original Manuscript: January 27, 2005
Revised Manuscript: February 24, 2005
Published: April 4, 2005

Abhijit Chakraborty, Laird Thompson, and Michael Rogosky, "10-7 contrast ratio at 4.5λ/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks," Opt. Express 13, 2394-2402 (2005)

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  1. Debes, John H.; Ge, Jian; Chakraborty, Abhijit, �??First High-Contrast Imaging Using a Gaussian Aperture Pupil Mask,�?? Astrophys. J. Lett. 572L, 165-168, (2002) [CrossRef]
  2. Debes, John H.; Ge, Jian; Kuchner, Marc J.; Rogosky, Michael �??Using Notch-Filter Masks for High- Contrast Imaging of Extrasolar Planets,�?? Astrophys. J. 608, 1095-1099, (2004) [CrossRef]
  3. Wilhelmsen Evans, Julia; Sommargren, Gary; Poyneer, Lisa; Macintosh, Bruce A.; Severson, Scott; Dillon, Daren; Sheinis, Andrew I.; Palmer, Dave; Kasdin, N. Jeremy; Olivier, Scot, �??Extreme adaptive optics testbed: results and future work,�?? Proc. SPIE 5490, 954-959, (2004) [CrossRef]
  4. Kasdin, N. Jeremy; Vanderbei, Robert J.; Spergel, David N.; Littman, Michael G., �??Extrasolar Planet Finding via Optimal Apodized-Pupil and Shaped-Pupil Coronagraphs,�?? Astrophys. J. 582, 1147-1161, (2003) [CrossRef]
  5. Vanderbei, Robert J.; Kasdin, N. Jeremy; Spergel, David N., �??Checkerboard-Mask Coronagraphs for High-Contrast Imaging,�?? Astrophys. J. 615, 555-561, (2004) [CrossRef]
  6. Kuchner, Marc J.; Spergel, David N., �??Notch-Filter Masks: Practical Image Masks for Planet-finding Coronagraphs, �?? Astrophys. J. 594, 617-626, (2003) [CrossRef]
  7. Kuchner, M.J. , �??A Unified View of Coronagraph Image Masks,�?? preprint no. astro-ph/0401256 at htp://xxx.lanl.gov/archive/astro, (2004) <a href=" htp://xxx.lanl.gov/archive/astro, (2004)">htp://xxx.lanl.gov/archive/astro, (2004)</a>.
  8. Debes, John H.; Ge, Jian, �??High-Contrast Imaging with Gaussian Aperture Pupil Masks,�?? PASP, 116, 674-681, (2004) [CrossRef]
  9. Nakajima, T.; Oppenheimer, B. R.; Kulkarni, S. R.; Golimowski, D. A.; Matthews, K.; Durrance, S. T., �??Discovery of a Cool Brown Dwarf,�?? Nature 378, 463-464, (1995) [CrossRef]
  10. Oppenheimer, Ben R.; Sivaramakrishnan, A.; Makidon, R.B., �??Imaging Exoplanets: The role of small Telescopes,�?? in The Future of Small Telescopes in the New Millennium, T. Oswalt, ed., III, (Dordrecht: Kluwar), p.157-174, (2003)
  11. Oppenheimer, Ben R.; Digby, Andrew P.; Newburgh, Laura; Brenner, Douglas; Shara, Michael; Mey, Jacob; Mandeville, Charles; Makidon, Russell B.; Sivaramakrishnan, Anand; Soummer, Remi; and 7 coauthors, �??The Lyot project: toward exoplanet imaging and spectroscopy,�?? Proc. SPIE 5490, 433-442, (2004) [CrossRef]
  12. Spergel, D.N., �??A New Pupil for Detecting Extrasolar Planets,�?? preprint no. astro-ph/0101142 at http://xxx.lanl.gov/archive/astro, (2001) <a href= "http://xxx.lanl.gov/archive/astro, (2001)">http://xxx.lanl.gov/archive/astro, (2001)</a>.
  13. Kuchner, Marc J.; Traub, Wesley A., �??A Coronagraph with a Band-limited Mask for Finding Terrestrial Planets,�?? Astrophys. J. 570, 900-908, (2002) [CrossRef]
  14. Sivaramakrishnan, Anand; Lloyd, James P.; Hodge, Philip E.; Macintosh, Bruce A., �??Speckle Decorrelation and Dynamic Range in Speckle Noise-limited Imaging,�?? Astrophys. J. Lett. 581, 59-62, (2002) [CrossRef]
  15. Thompson, Laird A.; Xiong, Yao-Heng, �??Laser beacon system for the UnISIS adaptive optics system at the Mount Wilson 2.5-m telescope,�?? Proc. SPIE 2534, 38-47, (1995) [CrossRef]
  16. Thompson, Laird A.; Castle, Richard M.; Teare, Scott W.; McCullough, Peter R.; Crawford, Samuel L., �??UnISIS: a laser-guided adaptive optics system for the Mt. Wilson 2.5-m telescope,�?? Proc. SPIE 3353, 282-289, (1998) [CrossRef]
  17. Thompson, Laird A.; Teare, Scott W., �??Rayleigh Laser Guide Star Systems: Application to the University of Illinois Seeing Improvement System,�?? PASP 114, 1029-1042, (2002) [CrossRef]
  18. Thompson, Laird A.; Teare, Scott W.; Crawford, Samuel L.; Leach, Robert W., �??Rayleigh Laser Guide Star Systems: UnISIS Bow-Tie Shutter and CCD39 Wavefront Camera,�?? PASP 114, 1143-1149, (2002) [CrossRef]
  19. Thompson, Laird A.; Teare, Scott W.; Xiong, Yao-Heng; Chakraborty, Abhijit; Gruendl, Robert, �??Progress with UnISIS: a Rayleigh laser-guided adaptive optics system,�?? Proc. SPIE 5490, 90-96, (2004) [CrossRef]
  20. Handbook of Microlithography, Micromachining and Microfabrication Vol. 1, Rai-Choudhury, P., editor SPIE Optical Engineering Press ; London, UK : Institution of Electrical Engineers, (1997)
  21. Sivaramakrishnan, Anand; Koresko, Christopher D.; Makidon, Russell B.; Berkefeld, Thomas Kuchner, Marc J., �??Ground-based Coronagraphy with High-order Adaptive Optics,�?? Astrophys. J. 552 397-408, (2001) [CrossRef]
  22. Trauger, John; Burrows, Chris; Gordon, Brian; Green, Joseph; Lowman, Andrew; Moody, Dwight; Niessner, Albert; Shi, Fang; Wilson, Daniel, �??Coronagraph contrast demonstrations with the High Contrast Imaging Testbed,�?? Proc. SPIE 5487, 1330-1336, (2004) [CrossRef]

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