How It Works

How CrystalEyes Works

Stereo-vision works by displaying left and right eye views "simultaneously". In reality, the left eye view is shown while the eyewear shutters block the right eye. Then the right image is shown while the left eye is blocked. At 120 Hz, each eye will see the appropriate image 60 times per second. Though the images aren't really shown at the same time, the switching is so rapid, that left and right views appear to be simultaneous. This emulates how natural vision works — with two eyes — thus creating depth perception.

Creating this effect requires an image that contains both left and right eye views.  Many high-end workstations can swap left and right images from video memory to screen using functions in OpenGL.  However, CrystalEyes® can work on systems that don't support this without any special software functions. 

Viewing a stereo images can be accomplished very simply.  This happens when the CrystalEyes emitter doubles the sync pulse of the monitor from 60 Hz to 120 Hz. This means that half the image is stretched out and drawn to the full screen, then the CrystalEyes emitter sends another sync pulse so that the monitor returns to the top to draw the other half, all in one cycle. The net effect is that within one cycle both left and right images are drawn.

The diagram below shows what a stereo images looks like before the emitter is turned on.

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