Night vision device is a device that can observe objects at night. It uses various technological means such as infrared technology and optical imaging technology, so that the human eye can see farther and clearer targets when searching for objects. In the design of night vision devices, the movement of human eyes when visually searching has the following meanings:

1. Improve the detection ability of the night vision device: the human eye's saccade, tracking and other movements can make the night vision device more sensitive to the existence of the target, thereby improving the detection ability of the night vision device.

2. Enhance the usability of the night vision device: the human eye will constantly adjust the focus when searching for objects, so that the night vision device can display the target more clearly. This movement also helps night vision goggles work more accurately in low-light conditions.

3. Improve the adaptability of the night vision device: the movement of the human eye will change with changes in light, environment and other factors, and this change will also affect the imaging quality of the night vision device. Therefore, when designing night vision devices, it is necessary to take into account the impact of human eye movement on imaging quality and perform targeted optimization.

To sum up, in the design of night vision devices, the movement of human eyes during visual search has multiple meanings such as improving the detection ability of night vision devices, enhancing the usability of night vision devices, and improving the adaptability of night vision devices.