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• MADA
• MAI
• MC
• mesotrophic
• microtubule
• MTF
  • definition
  • measurement

MTF measurement.

The definition of the MTF implies that, the MTF of an imaging process can be measured by analyzing images of a number of bar-patterned targets with sinusoidally varying reflectance. However, such an approach would have required repeating this measurement for many targets and would represent MTF only at discrete spatial frequencies. A more comprehensive measurement method, allowing simultaneous measurement over a range of spatial frequencies relies on the use of a step-reflectance object: two parellel bars of uniform high and low reflectance, respectively, are present (for example, Wyatt CL 1991, p. 197). Such methods are not shift-invariant, i.e. they depend on where the object reflectance changes appear in the image (for example, Daniels A et al 1995). Recently, a concise method has been introduced (Levy E et al 1999, Daniels A et al 1995) for measuring the MTF in a wide spatial frequency range at once by using a "white noise" shift-invariant random object. See also modulation transfer function, measurement. [MJ]