The holographic lenses in original HoloSpex Glasses are binary amplitude digital computer generated holograms. One drawback of binary amplitude and binary phase holograms is the presence of an upside down and backwards version of the holographic image. In many cases, like the heart images to the right, the user is entirely comfortable with the reversed copy. In some cases, the reversed copy proves to be distracting. Multilevel phase holograms are capable of eliminating the reversed holographic image. The removal of the reversed copy allows for a larger design area and can accomodate more complicated images such as the Santa image at the right. We have developed in-house capability of fabricating multilevel phase holograms. This new capability enables a variety of new digital holographic products. Current stock patterns based on the new techonlogy include | 
