Quadibloc writes:

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Of course! A 1X microscope objective with a two-foot aperture. You're a
genius!

On May 18, 9:30*pm, Richard J Kinch <ki...[at]truetex.com> wrote:
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The question was whether it could be done with whatever technology is
used to make 3D displays, at least as I understood it.

It could not be done, for example, with vertical strips and slots,
because that changes which eye an image goes to, not its distance for
focusing. Holography is another technique used for 3D displays.

Of course lenses could do it, just generate a real image floating in
air a few inches from someone's eyes if that person is nearsighted.
But a giant thick lens is not comparable to any technology used for 3D
displays, so I didn't count the question as being about that as an
alternative.

John Savard

Helpful person writes:

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I don't follow that reasoning. We're postulating refractive optical
elements, not holograms.

On May 18, 11:30*pm, Richard J Kinch <ki...[at]truetex.com> wrote:
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For the same reason that you can't use a hologram of a microscope lens
to replace the lens. You can get correct reconstruction only at one
field position and one set of conjugates.

Quadibloc writes:

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The question was whether it could be done with lenses.

It's an old and worthwhile question. If eyeglasses make you see properly,
then why can't we invert the system and put "object glasses" on things to
make us myopes (or whatever your refractive error) see them properly
without having to have apparatus on our heads.

On May 18, 4:59*pm, Quadibloc <jsav...[at]ecn.ab.ca> wrote:
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I didn't say it wasn't.

On May 9, 2:23 am, Richard J Kinch <ki...[at]truetex.com> wrote:
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Actually, this isn't really an issue with a holographic display, but
since holographic displays don't yet exist, the kind of 3D displays
which do exist don't imply that any technology would exist that would
help.

In the case of a holographic display, able to create any arbitrary
light wavefront, if the corrective lens has to be within 1 cm of the
eye... then the only constraint is that the position of the head with
respect to the laptop has to be controlled to a tolerance of 1 cm.

Instead of bolting the laptop to one's head, it could even use
infrared sensors to monitor the position of one's head!

John Savard

On May 9, 9:39 pm, Helpful person <rrl...[at]yahoo.com> wrote:

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Geometrical distortion is trivial to compensate for.

John Savard

On May 5, 3:23 pm, "n...[at]bid.nes" <Alien8...[at]gmail.com> wrote:

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Oh, yes, holography would work, but I presume the OP isn't asking
about technologies that don't yet exist; he is asking if the fact that
certain types of 3D displays *already* exist would lead to something
that would work, which is not the case.

John Savard

On May 3, 7:34 am, Amir Michail <amich...[at]gmail.com> wrote:
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If your eyes don't focus on the laptop surface, then each point of
light on that surface is spread out over a larger area.

Since the relative phase of light from different parts of that surface
can't be controlled, destructive interference can't be created, so one
can't put anything on the laptop screen that would be seen as less
blurry than an ordinary sharp display; one can only make things worse.

John Savard