REQUEST FOR INFORMATION - Subsurface-to-Surface Imaging DESCRIPTION Visible optics (i.e., 450 to 600 nm) imaging of objects located at or above the water surface from subsurface sensors is an extremely challenging problem. The wind- and wave-driven deformation of the water-air interface is a major limitation to subsurface imagers, with degradation from surface refraction and scattering frequently resulting in unrecognizable image content. The Defense Advanced Research Projects Agency's (DARPA) Strategic Technology Office (STO) is requesting information on novel research ideas and approaches to enable improved imaging from subsurface sensor systems that mitigates the distortions caused by the water/air interface. Information is requested concerning the understanding of transmission and scattering phenomenology, and hardware and/or software approaches to successful imaging through the water-air interface. No funding has currently been allocated to this effort. A Broad Agency Announcement and/or other solicitation may or may not result from the findings of this RFI. As light encounters the undulating water surface, some of it enters the water where it continues to be scattered and absorbed. The image also abruptly acquires aberrations caused by refraction at the interface. The resulting image as taken by a subsurface camera is blurred, distorted, broken up and attenuated. In order to reconstruct the image, physical techniques or algorithms must be developed to counter degradations such as those caused by anisoplanatism and multiple images. Responses of interest may address the following or other related topics: 1. Image modeling through the water-air interface o sea state (gravity waves as well as capillary waves) o surf zone effects o sensor depth o water/air properties o apparent object elevation o chromatic aberration from wedge of water o resolution 2. Experimental observation of wave behavior as it affects visible optics imaging o small-scale slope statistics with particular attention to capillary waves 3. Image reconstruction approaches suitable for improved imaging through the water-air interface o hardware approaches such as adaptive optics o deconvolution algorithms o phase diversity o lucky images o image mosaicing o image patch techniques 4. Polarization effects o multiple looks o obtaining surface-shape information o diagnosing scattering 5. Environmental estimation o small-scale water/surface/air modeling and prediction o wave prediction o optics of capillary waves 6. Innovative sensor designs o precise, real-time mapping of the interface shape over the entrance pupil o minimizing anisoplanatism o adaptive optics for distortion-dominated images o fusing information from a non-optical sensor o an optional list of citations including URLs if available; The above should be submitted as MS Word, PDF, and/or MS PowerPoint documents. Respondents are encouraged to be as succinct as possible while at the same time providing actionable insight. Respondents must submit one original and four paper copies of the full response and one electronic copy of the full RFI response (in Microsoft Word, Adobe PDF, and/or Microsoft PowerPoint on a single CD ROM). Disks must be clearly labeled with RFI SN07-55, offeror organization, and points of contact. The full RFI response (original and designated number of hard and electronic copies) must be submitted to: DARPA/STO, Attn: Dr. Jennifer Ricklin, 3701 N. Fairfax Drive, Arlington, VA 22203-1714. Responses to this Request for Information (RFI) are due no later than 4:00pm, Local Time, Arlington, VA, on 5 November 2007. ANY INQUIRIES TO THIS REQUEST FOR INFORMATION MUST BE SUBMITTED TO
[email protected] NO TELEPHONIC INQUIRIES WILL BE ACCEPTED. DARPA/STO will host a web site in support of RFI SN07-55 Subsurface to Surface Imaging. The web site will contain information supplementary to this document such as Question & Answer lists in the event that clarifications are needed. The active URL for the web site is http://www.darpa.mil/sto/solicitations/SN07-55/index.html. DISCLAIMERS AND IMPORTANT NOTES This is an RFI issued solely for information and new program planning purposes and does not constitute a solicitation. Respondents are advised that DARPA/STO is under no obligation to acknowledge receipt of the information received, or provide feedback to respondents with respect to any information submitted under this Request for Information (RFI). In accordance with FAR 15.201(e) responses to this notice are not offers and cannot be accepted by the Government to form a binding contract. Responders are solely responsible for all expenses associated with responding to this RFI. Submissions may be reviewed by the Government (DARPA and/or AFRL) and Systems Engineering and Technical Assistant (SETA) contractors such as Solers, Sage Solutions, and Schafer Corporation.