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4. Resolution and Related Topics
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4.1 Resolution
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What does "resolution" mean in this context? --
In general terms, it is two-dimensional spatial resolution.
And what does THAT mean?

Well, it is the ability of producing two distinct image points out of two distinct object points, though they are very near neighbours.

... Quite a cloudy sentence instead of a definition. For example: When are two image points "distinct"; are they allowed to touch like in the numeral "8"?


Clearly "resolution" is related to image definition, crispness, and contrast.
But in my opinion, resolution can be defined clearly and quantitatively only with the aid of MTF.
For instance you could decide:
"resolution limit is a certain spatial frequency. At this frequency, the MTF has dropped to 20%."


Sad to say, you're going to understand this statement only after you've learned the meaning of "spatial frequency" and "MTF". This is treated in paragraph 4.2.


4.2 Modulation Transfer Function MTF       (omitted in this free edition)
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In this paragraph, spatial frequency is explained   and via gradual contrast degradation the reader is led to modulation transfer factor and to modulation transfer function.
The advantages of MTF usage are described. Understanding of MTF is deepened by stepping through an MTF measurement procedure.


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Last modified Nov.28th, 2002 23:48