Image quality and λFN/p for remote sensing systems

The ratio of the sampling frequency to the optical bandpass limit of an incoherent diffraction-limited optical system is a fundamental design parameter for digital imaging systems. This ratio is denoted by lambda FN/p, where lambda is the mean wavelength, FN is the system f/number, and p is the detector sampling pitch. The value of lambda FN/p for a remote sensing system can have a profound impact on the image quality and the utility of the acquired images. The interaction between lambda FN/p and image quality is sensitive to the system design parameters such as modulation transfer function (MTF), signal-to-noise ratio (SNR), and ground sampled distance (GSD). Image simulations and analysis are presented that illustrate the changes in image quality as a function of lambda FN/p. System design trades that may influence the determination of the optimal lambda FN/p for a remote sensing system are also discussed. (C) 1999 Society of Photo-Optical instrumentation Engineers. [S0091-3286(99)02107-8].