Crossgrid Detector, High Resolution Imager, Chandra

The High Resolution Camera (HRC) on the Chandra X-ray observatory consists of two components: microchannel plates (upper square) and a cross-grid detector (lower square). The detector itself has two layers of fine wires drawn orthogonally to create a two-dimensional grid system. A set of two 10 cm (4-inch) square microchannel plates sitting above the grid completes the detector system. The two components are separated to make them both visible for display. Normally they would be nearly in contact.

X-rays collected by Chandra's grazing incidence mirrors are converted to an electron flux by the set of microchannel plates. The charge out the bottom of the microchannel plate is transferred to the cross grid detector, which acts like a position-sensitive detector using technologies similar to that of the CCD. The location and amount of charge on the grid is processed to build an image of the source of X-rays. Images from the HRC on Chandra have provided data on high energy events in the universe such as the accretion of matter by supermassive black holes. This HRC was built at the Smithsonian Astrophysical Observatory.