| 摘要 |
The MTF (modulation transfer function) for an optical or electronic device(s) is evaluated over a substantial portion of an image signal. In a system (10) having one or more optical or electronic elements (18, 20) for obtaining an image of an object (16), means for obtaining a modulation transfer function comprising imaging means (18, 20) for imaging the object (16) in an image frame based on the elements (18, 20) and a processing system (22) for determining a modulation transfer function with respect to each of a plurality of locations within the image frame. The plurality of locations being substantially distributed within the image frame and the processing system (22) determines the modulation transfer functions with respect to the plurality of locations to obtain a composite modulation transfer function for at least part of the system. The composite MTF represents a global evaluation. Furthermore, the MTF for all or part of the system can be evaluated in situ.
|
