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When I first responded to John's question, I was not in my office and
didn't have a supply of textbooks to examine. Now that I'm in my
office, I find the same thing John said. Every book I examined says the
focal point is the place where paraxial rays come to a focus. That
makes the focal length always equal to the distance between the lens and
the focal point, just like John said he read.
I am surprised I have just now noticed this, thanks to John, because I
do not agree with this. It appears to me that the textbook convention
is not consistent with everyday use of the word by practicing physicists
as well as the general public.
For example, the textbooks also state that the focal plane is one focal
length behind the lens, and that the focal point is where the focal
plane intersects the lens axis.