Turn on the auxiliary lighting when the environment is dark, and adjust the brightness of the auxiliary lighting source according to the distance from the object being observed. Night vision devices use low-light detectors. When there is a certain light source in the environment (such as street lights, moonlight), there is no need to turn on the auxiliary light source. You only need to adjust the focal length of the objective lens to make the observed objects clear. Environmental requirements and precautions: The night vision device should be stored in a soft bag. The operating environment is -5℃~40℃, and the relative humidity does not exceed 80%. Night vision goggles should be stored in a clean, dry place to protect the lenses from moisture, mo-ld, heavy pressure, mechanical damage, moisture and solar radiation. If you need to clean the optical surfaces of the objective lens, eyepiece, and la-ser illumin-ator, you should first blow off small sand and dust, and then wipe the surface with a fine soft cloth. If the night vision device is not used for a long time, please recharge the battery frequently to prevent the rechargeable battery from failing.