Projector-Based HUD for a Vehicle Having An Increase In Contrast and Efficiency Via a Circular Polarizer

A projection unit for a field-of-view display device, which is configured to show a virtual image via reflection on a partially transparent reflection plate arranged in the field of view of a user, such as a vehicle window, includes a projector-based image generator having a projector and a projection screen illuminated thereby, wherein the projector is configured to generate a real image on the projection screen and the projection screen is configured to project the resulting light beam bundle in a predetermined shape and direction onto the reflection plate; and a contrast element arranged in relation to the projection screen and configured such that it is only passed by the light beam bundle originating from the projection screen and this is largely without attenuation, and it is passed twice by the ambient light incident on the projection screen and reflected thereon and eliminates it.