A lenticule is a small, lens-shaped structure found in various materials, often used in optics. These tiny lenses can be made from plastic or glass and are commonly used in applications like holography and 3D imaging. They help to focus light and create visual effects by manipulating how light rays interact with surfaces. In the context of printing, lenticules are often used in lenticular printing, which creates images with an illusion of depth or motion. This technique involves layering multiple images behind a lenticular lens, allowing viewers to see different images from different angles, enhancing the visual experience.