Signal and noise in modulation transfer function determinations using the slit, wire, and edge techniques

摘要: The modulation transfer function (MTF) of an idealized imaging system can be determined from the Fourier transform system's line-spread (LSF). Three techniques experimentally determining LSF require either a slit, wire, or edge. In this paper, these three are modeled theoretically to determine noise in calculated MTFs as spatial frequency resulting both quantum fluctuations and stochastic detector noise. compared using signal-to-noise ratio (SNR) MTF, defined MTF value standard deviation ensemble determinations independent measurements. It is shown that for specified photon fluence, edge method has highest SNR at low frequencies, while slit superior high frequencies. wire always inferior technique. This suggests preferable measuring parameters such low-frequency drop, high-frequency response. cross-over which methods equal (f(e)) quantum-noise limited systems width length over measured. For detector-noise systems, f(e) dependent on only. all but therefore increased by decreasing measured, smoothing tails LSF, fitting analytic expression.