For biological research, I need to print characters so tiny that 2 of them fit in less than 0.5 mm, which I will read under a microscope. I am currently printing from Excel at font size of 1.5, using a HP LaserJet 400M. The result is slightly larger than what I need it to be, but printing at size 1 produces unreadable results. How can I print a smaller font size but still get readable results? Are there specialized printers for that? Where could I find one?