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A
.gov website belongs to an official
government organization in the United States.
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A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The eyes focus on a single point in space. The angle of eye vergence relates to the distance of the focus point to the eyes. For a near point the vergence angle (α1) is larger than for a far point (α2). α represents the angle of eye vergence.
