See-through computer display systems

A head worn display for displaying a displayed image overlaid onto a see-through view of a surrounding environment that includes multiply folded optics, comprising:

• a. a solid prism with at least one optically powered surface and a planar surface that provides a first internal fold of an optical axis of an image light associated with the displayed image;
• b. a combiner that provides a second fold the optical axis associated with the image light;
• and
• c. wherein a flat plate reflector is bonded to the planar surface of the solid prism to provide a flat reflective surface to the solid prism.