A warning system for a vehicle is provided. The diffractive optical element is designed to disperse the light across one or more spots on the surface in a manner designed to create speckle patterns having substantially uniform intensities. Therefore, by providing a low power mode of limiting some functions of the mobile terminal, unnecessary battery consumption can be prevented. Each line of the image is formed from segments where two or more of the segments define a line of an image. , printed circuit boards, for separately controlling each component, power conductors and data busses. The moving averages are combined and this difference average is compared to a trigger threshold.