The N4000 service manuals mention this calibration file, which is essentially a 8.5" x 11" landscape document optimized for setting size, focus, etc::
QuoteUSMonitor_Adjust.tiff is a picture file that is the size of an 11 by 8.5 inch landscape page with some 12 point text and concentric squares. You can use any style of display to adjust brightness and focus. The standard size page display of the monitor adjustment file assists in adjusting proper display size.
Don't suppose this has shown up anywhere? Otherwise I might be tempted to re-create it...
I don't have the original file but here's a quick test pattern created on
https://testpatterngenerator.com/. It needs to be converted to a tiff. I'm not sure if that will help or not but it might be useful for some of the monitor adjustments.