Focus of projection lens and Fresnel lens

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I do not know if the forum is still active ...
I want to build a home projector, splitt design and there is some detail I can not understand,
I searched through posts and there are many opinions that get confused.
My question: where is the focus of the frontal Fresnel lens should be, and where the focus of projection lens should be?

There is an opinion that says that the focus of the Fresnel lens should be equal to or larger focus of the projection lens.
And there is an opinion that the focus of Fresnel lens should be smaller than the projection lens, so that the Fresnel lens will be focused into the projection lens

Can someone please help me?
:confused::(:confused:
 
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.