ETS85
From Night Vision Wiki
The ETS85 is a Resolution testing device for night vision systems, manufactured by STC. One side contains a control panel with a power switch, Generation 2 / Generation 3 switch and a High light / Low light switch. Another side has an optical window which the night vision device to be tested is pointed into. A standard 1951 USAF resolution test chart can then be seen through the device, so that the resolution can be determined.
