It occurred to me that if the Nipkow disk was askew, relative to the viewer (that is, if the image is on the right, and the disc center is closer than the right edge, and the left edge of the disc is closer still), then there would be some visual correction of the "wedge" shape of the typical Nipkow display. Also, the curved scanlines would appear to straighten (slightly?).
Of course, the skewed image would be much narrower than needed, so this would be corrected by making the holes in the Nipkow disc wider and further apart (and hence the image area larger on the disc itself). The holes' width could also be adjusted to remove any apparent line thickness changes. When viewed from directly in front (with an askew disc), the image would look less Nipkow-like. I think.
If the same hole reconfiguration was used, then the disc could be used in normal configuration, and the correction could be done by a pair of mirrors in front of the display -- the first reflecting the display 45 degrees or so to the second, alongside, which reflects the image to the eye. By rotating the mirrors around the vertical axis, one could correct the 'askewness'.
Just thought I'd throw this idea 'out there' for posterity.
Cheers
A