| 摘要 |
Heads-up and heads-down displays employing holographic stereograms are provided. The stereograms can be oriented perpendicular to the user's line of sight (the "90.degree. case") or at angle to the line of sight (the "non-90.degree. case"). The stereograms are produced using a three-step process in which a series of two-dimensional perspective views are prepared, a H1 hologram is prepared from the two-dimensional perspective views, and a H2 hologram is prepared from the H1 hologram. For the non-90.degree. case, the two-dimensional perspective views are oriented at an angle relative to the plane of the H1 hologram during the preparation of that hologram. Similarly, during the preparation of the H2 hologram for this case, the H2 hologram is oriented at an angle relative to the H1 hologram. In this way, the viewing slits generated by the holographic stereogram are located in the vicinity of the user's eyes for the non-90.degree. case as is desired. In certain embodiments, the two-dimensional perspective views are transformed prior to being recorded on the H1 hologram. |
