SPI Coded Mask
Date: 07 June 2000
Copyright: Photo courtesy INTA, Spain
The hexagonal coded aperture mask of SPI is located 1.7 m above the detection plane in order to image large regions of the sky (fully coded field of view = 16 degrees) with an angular resolution of 2 degrees.
The mask is made of 3 centimetre thick tungsten and consists of 127 hexagonal elements, of which 63 are opaque, 64 transparent.
Last Update: 1 September 2019