CNN Forensic Files March 8, 2015 05:38:00
When dry, they could be examined with a video spectral compartor, or vsc, which combines digital engineering with a full range of infrared light sources, in order to visualize writing that is not discernible with the naked eye. this technology can show where alterations have been made on a check with the various light sources. under an infrared luminescence setting, the different ink will glow. magnification can also detect when official documents have been altered. two pages of a legal contract appear the same. but under ultraviolet light, it reveals that one of the pages was added later. ind...
Source: archive.org