A fisheye lens is a lens with a short focal length and a field of view close to or equal to 180°. It is an extreme wide-angle lens, and "fisheye lens" is its common name. In order to maximize the photographic angle of view of the lens, the front lens of this photographic lens has a short diameter and a parabolic shape protruding toward the front of the lens, which is quite similar to the eyes of a fish, hence the name "fisheye lens", fisheye There are two kinds of lens imaging, one is like other lenses, the image is full of the picture; the other is circular. No matter what kind of imaging, the image taken with a fisheye lens is quite deformed and has a strong sense of perspective convergence. Therefore, it is often used as a special effect lens. The fisheye lens has a large field of view, so it is widely used in scene monitoring, satellite positioning, robot navigation, tiny intelligent systems, engineering surveying and other fields. Because fisheye lenses can achieve full-airspace tolerance and full-time real-time information acquisition, especially in line with the requirements of modern warfare for information acquisition technology, which is unmatched by other photoelectric detection methods, fisheye lenses are used in national defense and military The field has also been important applications. Fisheye lens is also suitable for spherical screen projection and special-shaped screen projection, such as the whole sphere, hemisphere and spherical crown projection in large museums and exhibition halls. The current dome projection projects mainly include: single projection (single projector placed near the center of the sphere), double stitching (two projectors are located at the two poles of the dome screen), and multiple splicing (mostly four, five and Above splicing). The fisheye lens produced by Wavefront has the following characteristics:

• High-definition resolution to ensure clear imaging.

• Large field of view, up to 210 degrees, can reach both sides of the road

• Image distortion is small, and some fisheyes are corrected by Tailore Distortion.

• Good uniformity of image surface illumination

• Long back focus, can be equipped with various projectors

• F# with relatively large and small aperture.