Night vision is not illegal for civilian use in the United States.
However there can be some restrictions placed on night vision, depending on the state you're in and how the night vision devices are used, most particularly in relation to firearms.
There are also no federal laws that prohibit the ownership or the use of night vision goggles or devices by civilians.
However certain states like California has specific restrictions when it comes to night vision devices.
For example in California it's illegal for you to attach any night vision devices to any firearms, especially the ones with infrared illumination.
And many states also have regulations that regard the use of the night vision for hunting and some allow it and others have restrictions or outright bans on the night vision devices.
Attaching of night vision equipment to any firearms is a common area of restriction although if you're on private property then you should be okay to do so if you desire.
Some states also have their own regulations on using night vision for hunting, which can vary depending on the type of animal and the specific equipment.
And the high end or military grade night vision devices may also have export restrictions on them.
As a civilian you can buy night vision devices although they are often less powerful than the military versions of night vision devices.
And the devices light night vision goggles or scopes for hunting are legal in most states although the civilian night vision devices don't offer the same capabilities as the military versions although they are still very good and useful.