A form of electro-optical camouflage (referred to also as optical camouflage, adaptive camouflage, active camouflage, chameleonic camouflage, and cloaking technology) is said to be 85-100% invisible to the naked eye from 20 feet away. The system is low weight and relatively cheap. Advanced American Enterprises (AAE) AAE uses the tem "invisibility stealth" to describe the effect of their tech, which, according to them renders an object, person, or vehicle 85-100% invisible to the human eye or video camera in the visible spectrum (visible light) as soon as you flip the switch to "on", even while the cloaked item is moving.
The technology does have limitations. AAE states in their literature that the Stealth Technology System's minimum effective distance is 20 ft for both Visibility Stealth and IR Stealth. In other words, the observer or detection device has to be at least 20 feet away from the cloaked object. 20" is still awfully close for someone not to be able to spot an APC or MBT (Main Battle Tank).
Previously on this site we indicated that metamaterials are being developed for invisibility