X-ray neutral density (ND) filters are heavily used in both commercial applications (radiology) and multiple NASA missions targeting X-ray and particle detection. State-of-the-art ND filters cannot offer uniform, wide energy band controllable density and are mechanically fragile. MicroXact Inc.is proposing to develop a hard X-ray ND filter set that offers extremely uniform density (controllable from below ND10 to above ND100) over very wide X-ray energy range (from below 1KeV to over 100KeV) that is mechanically and environmentally stable, light weight, affordable and highly scalable. The proposed X-ray ND fulters is based on macroporous silicon with proprietary conformal pore wall coating and pore orientation. In Phase I of the project MicroXact Inc. will finalize the performance specifications with NASA personnel, will design the 1-100KeV X-ray ND10, ND100 and ND1000 filters and validate the performance via modeling, will fabricate prototypes of ND10 and ND100 filters and will experimentally validate the proposed approach. Key fabrication process for the proposed ND1000 filter design will be demonstrated as well. The X-Ray ND filters developed on this SBIR project will be commercialized in Phase III.
Due to the unique features (uniform and controllable X-ray attenuation over very broad X-ray energy range) over competing technologies, the proposed MPSi X-Ray neutral density filters are expected to find a number of applications in NASA missions (LUVOIR, HabEx, Lynx, New Frontier-IO, and many more). Similar concept will work equally well for other NASA missions (such as ATHENA X-IFU and X-ray Surveyor, etc.).
Similar design of the particle and X-ray ND filters and attenuators is expected to find considerable DoE applications spanning from plasma parameter monitoring in tokamaks, X-ray and particle detection in accelerators, lightning and aurora studies, etc. However, the biggest market for the proposed component is X-ray attenuators for medical radiology.