The term "fisheye" primarily refers to a type of ultra wide-angle camera lens that produces strong visual distortion to create a wide panoramic or hemispherical image. Unlike regular lenses that keep straight lines straight, fisheye lenses produce images with a characteristic convex, curved appearance, mimicking the broad, rounded view similar to what a fish might see underwater. The angle of view is typically between 100 and 180 degrees, sometimes even wider, causing the distinctive wide and curved perspective seen in fisheye images.
Additionally, "fisheye" can sometimes refer to the actual eye of a fish or aquatic creature resembling a fish, but in most common contexts, especially photography and optics, it refers to this unique lens type.
In summary, "fisheye" means an ultra wide-angle lens with a curved distortion effect that produces a wide, panoramic image with a rounded appearance.
