Image plane holography customarily has a limited-parallax viewing field, usually caused by the frame of the master hologram. This limits the viewing audience to one or two people at a time, with no visible image for off-axis viewers. A partial solution is to use a larger master, which creates a larger viewing window to extend the size of the viewing field. This new method extends the captured field beyond the edges of the recording plate, using flat mirrors on either side of the master hologram to reflect otherwise unrecorded side views. These side views are reversed and superimposed over the object wave during recording of the master hologram. After the hologram is processed and illuminated, these mirrored side views are part of the reconstructed wavefront. When reverse-illuminated in the copy set-up for reconstructing and copying the real image, the same side mirrors, now placed into the copy system along with the master, reflect the projected side views back to the original object position. A copy hologram recorded at the image plane receives all the reassembled reflected views as well as the direct object wavefront. The field of view is no longer limited by the size of the master window, but by other factors such as coherence length, mirror alignment, or distortion of the recording media. Several experimental mirror arrangements are presented, including reflection hologram copies with parallax enhancement on all four sides of the master plate, rainbow transmission copies with multiple colors and multiple channels, and different mirror positions and sizes.
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