CRITICAL-ANGLE TRANSMISSION (CAT) GRATING Scanning electron micrograph of the hierarchical structure of a large-area CAT grating membrane fabricated from a silicon-on-insulator wafer. Shaping of thin-foil x-ray optics X-ray optics for space-based applications need to be wafer-thin AND maintain accurate figure. Home of the MIT Nanoruler The Nanoruler is the first tool to implement the patented patterning technique called Scanning Beam Interference Lithography (SBIL). ( Volker Steger, Science Photo Library) The Chandra X-Ray Observatory The SNL fabricated hundreds of transmission gratings for the High Energy Transmission Grating Spectrometer on board of Chandra, launched in 1999, and still operating. (Image credit: NASA/CXC/SAO) X-ray optics shape correction using ion implantation Ion implantation of thin-foil x-ray mirrors has the potential to correct figure at the sub-arcsec level. ( Ralf Heilmann) The innovative Critical-Angle Transmission (CAT) grating combines the best of transmission and reflection gratings in the soft x-ray band... We are pioneering alternative methods for the shaping and figure correction of thin-foil optics utilized as grazing-incidence mirrors in space-based x-ray telescopes... The Nanoruler is a prize-winning tool for the rapid high-precision patterning of large-area gratings... Oct. 2015: Pt-coated CAT gratings extend blazing to harder x rays and larger angles! (unpublished)
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Space Nanotechnology Laboratory | MIT Kavli Institute for ...