Staring FPA devices are coming to a state of performance and maturity. However, they are still the major defect source of the modernized E/O systems. MTF may act as a promising tool in evaluating their system requirements. Following a review of the MTF measurement technology, the evaluation of a PtSi Schottky-barrier FPA camera with one of the methods is given. It shows that a new MTF standard should be established when this type of test is applied to a discretely sampled staring array system. Current efforts have been made in our laboratory for this purpose. Detailed MTF results are presented for discussion, and we believe that it is necessary to include the CTF data at Nyquist ratio.