NASA SBIR 2005 Solicitation


SUBTOPIC TITLE:High Contrast Astrophysical Imaging
PROPOSAL TITLE:Ultraflat Tip-Tilt-Piston MEMS Deformable Mirror

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Boston Micromachines Corp
108 Water Street
Watertown ,MA 02472 - 4696
(617) 926 - 8796

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Paul   Bierden
108 Water Street
Watertown, MA  02472 -4696
(617) 926 - 8796

It is proposed to develop a process for producing arrays of hexagonal mirror segments with deviation from flatness smaller than 1nm RMS over a 600?m segment span, using novel microfabrication techniques. Each segment will be rigid enough to withstand actuation (piston, tip, and tilt) by a triad of flexure-based electrostatic actuators that have already been demonstrated by the project team. The base for the mirror will be a conventionally surface micromachined silicon film, augmented by a thick epitaxial layer of silicon. Subsequently, this layer will be polished, annealed to relieve stresses, and then coated with a thin film of protected silver. The combined result of thickening, polishing, and annealing will produce segments that are flatter, by more than an order of magnitude, than any micromachined mirror segments that are available today. Preliminary data demonstrate some promise that these processes can be combined effectively. Such an array of mirror segments would constitute a significant technological milestone and an essential component for the visible nulling coronagraph instruments planned for the terrestrial planet finding (TPF) mission. The project team has considerable experience in fabricating micromirror arrays for laser communication, astronomical imaging and visions science applications and BMC is a world leader in the production of commercial high resolution wavefront controllers. The project leverages a existing successful relationship between BMC and JPL.

The proposed technology will be a useful tool for the Terrestrial Planet Finder Mission. It will be particularly suitable for insertion in the High Contrast Imaging Testbed (HCIT) at JPL. One built-in capability of HCIT is to test alternative coronagraph concepts developed under industry and university contracts. The modularity of HCIT allows integration of guest user modules such as the proposed ?DM through a program scheduled to commence in FY2004. The proposed mirror will be designed specifically to be compatible with HCIT. It is expected that success of this work will lead to further evaluation of MEMS DMs in science and technology missions that precede and follow TPF. All but one of the seven precursor missions calls for active optics. It is expected that deformable mirror technology will play an ever-increasing role in astronomical imaging systems, as competing requirements for increased resolution and lighter weight primary mirrors push the technology forward.

The processing technology developed in this program will allow the future development of deformable mirrors for non-NASA applications as well. Ultra-flat highly reflective mirror surfaces are required for a number of commercial applications. Examples of these applications include high power lasers and optical lithography. Leaders in both of these markets are currently exploring the use of adaptive optics to enhance performance of their optical systems. There is currently no commercially available deformable mirror capable of producing the high quality wavefront that could be achieved using the proposed mirror technology.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Large Antennas and Telescopes
Optical & Photonic Materials
Semi-Conductors/Solid State Device Materials

Form Printed on 09-19-05 13:12