The present invention is directed to methods and an apparatus for reading, displaying, and transmitting data obtained from Small Form-factor Pluggable (SFP) optical modules and 10 Gigabit Small Form-factor Pluggable (XFP) optical modules, as well as other type of optical modules. In accordance with one exemplary embodiment of the invention, a small handheld unit including an LCD (liquid crystal display) panel, an electrical interface circuit, a battery, and a user-operated switch, is used to interrogate an inserted optical module.