Heliodisplay images are not holographic although they are free-space, employing a rear projection system in which images are captured onto a nearly invisible plane of transformed air. What the viewer sees is floating mid-air image or video. These projected images and video are two-dimensional, (i.e. planar) but appear 3D since there is no physical depth reference. While conventional displays have the benefit of being attached to a physical substrate, Heliodisplay projections are suspended in air, so you will notice some waviness to the quality of the projections.

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Viewing a Heliodisplay image in direct sunlight is almost impossible. Images can be seen up to 75 degrees off aspect for a total viewing area of over 150 degrees- similar to an LCD screen

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One of the most frequent questions we get at Pangolin is: "How do I make 3D images float in mid-air?" This question probably comes because many people have seen special effects such as the "Princess Leia" scene from Star Wars.
Unfortunately, there is no such thing as a floating-in-midair 3D holographic freespace projection. There are various ways of approximating such a projection;

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Dr Persinger wrote an article a few years ago, titled "On the
Possibility of Directly Accessing Every Human Brain by
Electromagnetic Induction of Fundamental Algorithms".[18] The
abstract reads:

"Contemporary neuroscience suggests the existence of fundamental
algorithms by which all sensory transduction is translated into an
intrinsic, brain-specific code. Direct stimulation of these codes
within the human temporal or limbic cortices by applied
electromagnetic patterns may require energy levels which are within
the range of both geomagnetic activity and contemporary
communication networks. A process which is coupled to the narrow
band of brain temperature could allow all normal human brains to
be. affected by a subharmonic whose frequency range at about 10 Hz
would only vary by 0. 1 Hz."

He concludes the article with this:

"Within the last two decades a potential has emerged which was
improbable, but which is now marginally feasible. This potential is
the technical capability to influence directly the major portion of
the approximately six billion brains of the human species, without
mediation through classical sensory modalities, by generating
neural information within a physical medium within which all
members of the species are immersed.

from here - an oldie but a goldie.

www.raven1.net...