Spectacle lenses are often formed such that light bundles of pixels of the generated image are coupled into the spectacle lens via a coupling-in section, guided in the spectacle lens by total internal reflection on the front and the rear side to a coupling-out section and deflected there such that a coupling-out takes place via the rear side of the spectacle lens.
In the case of the coupling-in section the difficulty can arise that after total internal reflection on the rear side an already coupled-in or deflected bundle of beams strikes the coupling-in section again and is there deflected in an undesired manner such that it is converted into stray light. In order to prevent this, the thickness of the spectacle lens would have to be increased (for example to within the range from 10 to 20 mm), which is, however, undesired. Alternatively, the field of view and/or the size of the exit pupil or eyebox could be reduced, which is also undesired, however.
USPTO Backgrounds
USPTO Backgrounds