For this experiment the diffuser is placed at a position which is 20 mm greater than the normal fibre position. In between diffuser and fibre is a teflon "light tunnel". The cosine response is shown below:
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The graph shows that the cosine response does not change dramatically, altough it improves a little.
This suggest that the diffusers do not necessarily have to be used in combination with a fibre. The diffuser keeps a good cosine response and thus the diffussers can aswell be used with an open slit and a "light tunnel" in between fibre and diffuser.
Info, questions and remarks, contact: Richard McKenzie