Other technologies have been developed to project light dots in the air above a device. An infrared laser is focused on the destination in space, generating a small bubble of plasma which emits visible light. Up to now (August 2008) the experiments only allow a rate of 100 dots per second. One of the issues which arise with this 3D display system is the use of technologies that could be harmful to human eyes.
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Stereoscopic
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Autostereoscopic
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Volumetric
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Holographic
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Passive
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Tracking
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Multiview
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Addressed media projection (air or solid)
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Moving lightpoints
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Layered
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|
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Features
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User Benefits
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|
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HoloVizio -light field
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Lenticular
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Parallax barrier (controlled)
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Different opt. Rasters and filters
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Integral Imaging
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Time-multiplex
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Controlled pixel technology
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Passive (moving screen)
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Active (rotated led matirx)
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Double
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Multilayer
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|
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Continuous motion parallax
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The 3D image doesn't "jump" between the views, horizontal perspective is perfect
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N
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Limited
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TRUE, horizontal only
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N
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N
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N
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N
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N
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N
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True, also vertical
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True, also vertical
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True, also vertical
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True, also vertical
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True, also vertical
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True, vertical also possible
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There's no contradiction between eye-convergence and focusing
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No discomfort, seasickness or disorientation
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Y
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N
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Y
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N
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N
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N
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Y
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N
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N
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Y
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Y
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Y
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Y
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Y
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Y
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Voxels can be individually addressed
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The point of a given view does not move if the viewer is moving and is exactly there where it seems to be
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N
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N
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Y
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Limited
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Limited
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Limited
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Limited
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Limited
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Y
|
Y
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Y
|
Y
|
Y
|
Y
|
Y
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Wide viewing angle, optional viewing distance
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Collaborative use
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N
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N
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Y
|
Y
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Y
|
Y
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N
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
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Limited
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No eye or head tracking used
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Not necessary to stand in one point, free motion possible
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N
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Limited
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Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
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No latency
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Y
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N
|
Y
|
Y
|
Y
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Y
|
Y
|
Y
|
Y
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Y
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Y
|
Y
|
Y
|
Y
|
Y
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No invalid zones in the field of view
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The 3D image can be seen in the entire field of view
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Not relevant
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Y
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Y
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N
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N
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N
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N
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N
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Y
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Limited
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Y
|
Y
|
Y
|
Y
|
Y
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The points can be generated anywhere in the field of view
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Optional shaped objects or 3D view can be visualized
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In a fixed position only
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In a fixed position only
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Y
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Limited
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Limited
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Limited
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Limited
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Limited
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Y
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Limited
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Y
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Y
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N
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N
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Y
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Objects could appear behind and in front of the display screen
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Y
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Y
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Y
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Limited with depth
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Limited with depth
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Limited with depth
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Limited with depth
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Limited with depth
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Y
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N
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N
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N
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N
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Only with supplementary optics
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Y
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Ability to show hidden edges
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Wide scale of displayed images, textures vs. wire frame images only
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Y
|
Y
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Y
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Y
|
Y
|
Y
|
Y
|
Y
|
Y
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N
|
N
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N
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N
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N
|
Y
|
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Direction selective light emittance of each pixel
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Window-like view, all light beams are present as in natural view
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N
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N
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Y
|
N
|
N
|
N
|
N
|
N
|
Y
|
Y
|
N
|
N
|
N
|
N
|
Y
|
|
Full compatibility with optional software environment
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Ability to display any 3D information and to use different 3D sw without restrictions
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Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
N
|
N
|
N
|
N
|
N
|
Y
|
|
Compatible with current displaying conventions
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Easy replacement of desktop 2D monitors
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Y
|
Limited
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
N
|
N
|
N
|
Y
|
Y
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Limited
|
|
High refreshment rate possible
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Motion picture, interactivity
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Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
N
|
N
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Limited
|
Limited
|
Limited
|
Y
|
Y
|
N
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Brightness
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Visibility under various ambient lighting conditions
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Good
|
Good
|
Good
|
Good
|
Fair
|
Limited
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Good
|
Limited
|
Good
|
Limited
|
Limited
|
Limited
|
Fair
|
Good
|
Good
|
|
Resolution (X,Y)
|
Clear, sharp pictures
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Good
|
Good
|
Good
|
Fair
|
Fair
|
Fair
|
Fair
|
Fair
|
Good
|
Limited
|
Limited
|
Limited
|
Good
|
Good
|
Limited by speckle
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|
Depth resolution (Z)
|
Achievable depth of the 3D image
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Good
|
Good
|
Good
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Limited
|
Limited
|
Limited
|
Limited
|
Limited
|
Limited
|
Limited
|
Limited
|
Limited
|
Not relevant
|
Poor
|
Good
|
|
Color resolution
|
True colours
|
Good
|
Good
|
Good
|
Good
|
Good
|
Good
|
Good
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View number dependant
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Fair
|
N
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Poor
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Poor
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Good
|
Limited
|
Good
|
|
Practical display sizes
|
System can be built from small to large sizes
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Any
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Any
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Any
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Any
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Any
|
Any
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Any
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Y
|
Y
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Limited
|
Limited
|
Limited
|
Any
|
Any
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Limited
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|
No moving parts
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Reliability, proper lifetime, mobile applications, no noise
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Y
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True/Not true
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
|
Y
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N
|
N
|
N
|
Y
|
Y
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True/Not true (Scanning)
|
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Vision safe technology?
|
3D image generation may involve methods which could be dangerous to human eye, casue strains or disconforts.
|
None
|
Overlapping reality
|
Y
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View number dependant visual strains
|
Y
|
Y
|
Y
|
Laser and plazma radiation
|
Spinning hazard
|
Spinning hazard
|
Y
|
Y
|
Laser
|
A wide range of organisations have developed 3D displays, ranging from experimental displays in university departments to commercially available displays. Companies involved include: