New trends in physics teaching, v.4; The ... - unesdoc - Unesco

New Trends in Physics Teaching IV
Figure la. Projector showing both slide and image (on screen A).
b. Image if the screen is moved to position B.
c. Image if the screen is moved to position C.
In all three cases, the information about the slide is present in some form on the screen, although it is only completely intelligible
with the screen in position A.
The relationships between these distributions can be described in terms of the concept of
Fourier Transformation, or through the idea of the transfer function, or in various other ways.
For our purpose here, however, we wil use a very simple illustration to put over the idea.
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