I know that these and similar cameras are in use at the Postal Service. http://www.fairchildimaging.com/files/2kand4klvcameramanualrevc_001.pdf http://www.fair

I know that these and similar cameras are in use at the Postal Service. http://www.fairchildimaging.com/files/2kand4klvcameramanualrevc_001.pdf http://www.fairchildimaging.com/files/2kand4klvcameramanualr... I know from experience that you can read at least the outside page of a tri-folded letter through most envelopes on the address side. According to one of the Fairchild applications engineers, it is a problem with mail sorting systems, because they have to reject that noise to read the address properly. The Osprey camera has excellent sensitivity in both UV and Visible wavelengths.