Design and fabrication of multigrid X-ray collimators

The paper considers the design and fabrication of multigrid collimators for use in X-ray astronomy. The most important collimator performance criteria are minimum off-band transmission or leakage, and maximum on-band transmission. Lockheed experience with multigrid collimator is summarized: (1) an Oda type with one-dimensional collimation of 1.7 arc minute FWHM and using only the central transmission band, (2) an Oda type with 2 arc minute one-dimensional collimation using up to 27 transmission bands, each separated by 42 arc min. and (3) a modified Parkinson type with two-dimensional collimation of 40 arc sec. Attention is given to grid materials, precision, plating, hole quality, and results of acceptance testing.