Computer Link Corporation gizmo?

[Joe R.]

  Does anyone have any idea what this is?
<http://www.classiccmp.org/hp/laser/computer%20link.jpg>. The "sticks"
sticking out to the left are long skinny mirrors. Each one can rotate +/-
45 degrees by means of the knobs on the right side. One side of the
rotating mirror shows a number such as "1", when you rotate it it shows
"2", etc etc. This is the second one of these that I've found but the first
was all busted up.

   Joe