Head-up display image generating unit with folding mirror

A head-up display for a transport, comprising:

• an imaging unit for generating an image;
• an optical unit for projecting the image by a mirror unit,
• wherein the imaging unit has a folding mirror, wherein the folding mirror is arranged between a light source and a display element, through which the light source radiates light, at a work angle to a propagation direction of the light that is incident on the folding mirror from the light source, wherein the folding mirror has microstructures, wherein the microstructures have first mirror surfaces that are each arranged at a first angle, which deviates from the work angle of the folding mirror, and are spaced apart from one another to form gaps, wherein second surfaces are arranged in the gaps each at a second angle;
• a polarizer arranged upstream of and facing the display element on a first side and downstream of and facing the first mirror surface on a second side and configured to guide light having a first polarization to the display element and light having a second polarization into the gaps;
• and
• a retarder arranged upstream and directly facing the microstructures of the folding mirror and facing the second side of the polarizer and configured to convert polarization of the light guided into the gaps to the first polarization, and
• wherein the light guided into the gaps is guided in the direction of the display element after it has passed through the gaps.