1. Use of a Digital Micromirror Array as a Configurable Mask in Optical Astronomy Shawn Gilliam Advisor: Dr. William Hetherington Research Associate: Teal Pershing

2. DMA Apparatus 2 12” Cassegrain Telescope Digital Micromirror Array Charge Coupled Device DMA CCD Telescope Lens

3. 3 Zoomed Optical Transfer Function

4. Coronagraph 4

5. Lyot Stop 5 Aperture Masking Interferometry Primary Secondary Tertiary Aperture Mask Bold black represents the section of the primary mirror that is passed through the system.

6. Backlit holes in black cardboard with 0.5 cm separation, at 10 m. Angular separation of 100 ±20 arcseconds. 6 Dim Center Star

7. Pixels of a monitor, configured to a separation of 0.216 mm at 13 m. Angular separation of 3.4 ±0.1 arcseconds. 7

8. LED’s, one much brighter than the other, placed 0.4 cm apart at 40 m. Angular separation of 25 ±5 arcseconds. 8

9. 9 Profile plot across image at x = 370

10. Other Achievements 10 Fourier Transform Lab used in PH 481. Fresnel Zone Plate Mask Designs.

11. Conclusion The DMA Apparatus is a useful tool for optical astronomy. Angular resolution of 3.4 ±0.1 arcseconds. Light from bright sources can be reduced. 11

12. Future Directions Construct a workable apparatus that can be used for night viewing. Obtain a complete description of the Optical Transfer Function. Incorporate a variety of masking techniques. 12

13. References [1] “Robust Coronagraphy with an APP.” [Online]. Available: http://home.strw.leidenuniv.nl/~kenworthy/research/app/. [Accessed: 04-Jun-2012]. [2] Wikipedia contributors, “Coronagraph,” Wikipedia, the free encyclopedia. Wikimedia Foundation, Inc., 16-May-2012. [3] “DLP System Optics” Application Report DLPA022, Texas Instruments, July 2010. [4] Wikipedia contributors, “Speckle imaging,” Wikipedia, the free encyclopedia. Wikimedia Foundation, Inc., 17-Mar-2012. [5] “Presentation of the DLP Technology: Presentation part-one.” [Online]. Available: http://us.generation-nt.com/technology-dlp-video-projector-digital-light-processing- review-42606-2.html [Accessed: 05-Jun-2012]. http://us.generation-nt.com/technology-dlp-video-projector-digital-light-processing- review-42606-2.html [6] “Mimir Photo Archives – 20021217.” [Online]. Available: http://people.bu.edu/clemens/mimir/Photo_Archive_Pages/20021217.html [Accessed: 05-Jun-2012]. http://people.bu.edu/clemens/mimir/Photo_Archive_Pages/20021217.html [1]“APOD: 2008 January 11 - Polaris Dust Nebula.” [Online]. Available: http://apod.nasa.gov/apod/ap080111.html. [Accessed: 11-Jun-2012]. 13

14. 14

15. Fourier Transforms 15

16. Fresnel Zone Plate 16

17. 17 f f/3 f < f/3f/7