US Patent 10359689 Flashlight device

A flashlight device includes a light source and a flash lens. A microstructure film with a microstructure pattern is disposed on the flash lens. After plural light beams from the light source pass through the flash lens and the microstructure film, a flash of light is provided to an environment. The plural light beams are shaped by the at least one microstructure film while the plural light beams pass through the microstructure film, and/or a spectrum distribution of the plural light beams is modulated after the plural light beams pass through the microstructure film.