A test conducted by researchers at the University of California, San Francisco, shows that the Google Glass device creates a blind spot in the wearer's peripheral vision.

The researchers tested three wearers. They compared their findings to tests using the Google Glass, then with ordinary glasses of similar colour and similar temples.

The results of all three participants show that the device creates a blind spot, causing a significant visual obstruction in the upper right quadrant.

Also, analysis of the photos of 132 wearers shows that people tend to place the Google Glass device near or above their pupillary axis, which can cause blind spots and interfere with vision.

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