SBIR recommends at least four 4-bar targets be used to develop a MRTD curve. The following sheet formulates the spatial requencies. Each of the targets are based on particular camera parameters and collimator focal length.

The formulated target frequencies are related to the Nyquist frequency (symbol Fo) of the unit under test, SBIR typically suggests 0.2, 0.5, 0.8 and 0.95 of the Nyquist frequency (Fo)

4-Bar Target Calculator

The first step is to Calculate the IFOV of your sensor and use that result in the section below:






Nyquist limit when a starring array has a 100% fill factor


Results

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Max bar width for 312 0.1616 Inches
Max bar width for 313, 316 & 317 0.2727 Inches
Max bar width for 314 0.1252 Inches
Max bar width for 315 0.485 Inches