Active stereoscopy
Principles of active stereoscopic visualization
 The key principle of active stereoscopic visualization is fast switching between two different images. Monitor, special TV or special DVD projectors very fast switches during the visualization between left and right eye images. Special glasses (soled usually shutter-glasses) a connected through IR or by a cable with the projection device. Odd images are visible only in one eye, the even images are visible in the second eye. The glasses use fast switching LCD panel for hiding the image from opposite eye. For enough high frequencies (100 Hz an higher) the switching is hard to notice. For lover frequencies, the quality of stereoscopic perception is affected by flickering problems. This system could be used in combination with PC monitor efficiently. One of the great advantages of active stereoscopic projection is standard projection screen usage.
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Monitor or projector generating two different images at hi frequency (100 - 120 Hz). LCD shutter-glasses synchronized with image source alternate between left and right eye view.
Advantage:
Full color. Standard projection screen. Works perfect with standard CRT monitors.
Disadvantage:
Each user must wear expensive shutterglasses. The specialized DLP projectors are expensive. |
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Comparison of different 3D stereoscopic visualization techniques
Technology |
Color information |
Resolution |
Suitable for projection |
Monitor based visualization |
Number of observers |
Cost |
Anaglyph |
complete lose |
middle |
yes |
yes |
high |
very low |
Active stereoscopy |
full |
high |
yes |
yes (no LCD) |
restricted |
high |
Passive stereoscopy |
full |
high |
yes |
no |
high |
middle |
Autostereoscopic monitor |
full |
middle |
no |
yes |
very restricted |
high |
The table table demonstrates suitability of different stereo visualization methods. |
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Czech language |
English language |