摘要 |
<p>An achromatic flat-panel projection display comprises a video projector 2a, a condensing lens (26) and a tapered transparent slab spreading the image input from the projector over the area of the slab. To compensate for dispersion in the slab a dispersive prism is used at the input edge of the slab, whose dispersion cancels out the dispersion of the slab. The prism can be a separate part of simply a bevel in the input edge, i.e. the thick end of the slab.</p> |