Zero back focus distance for diy lens ? Is it possible and how to design ?

Zero back focus distance for diy two element anamorphic lens ?

I am thinking for a idea to order water jet cut anamorphic glass lenses. I want two anamorphic lenses from same glass block but I want something more unusual. I have read imax lenses have zero back focus distance and is it easy or impossible with that setup ?

I want film touches the cylinderical lens flat area and slides on it.

Umut

I think back focus area does not need to be curved but could be flat. Design became easy.
here is a rendering from google.



please read above post.

Umut