Specifications

GLOSSARY
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Draft. Preliminary, Confidential.  1995 Apple Computer, Inc. 11/20/95
over scan Overscan moves the screen image as
close to the edges of the screen as possible
without distorting the image. This setting is
useful when you are using the AppleVision
displays to view videos.
pincushioning This term describes distortions
of the screen image, where the sides of the image
either bulge out to create convex pincushioning,
or are pulled in to create concave pincushioning.
smart displays These displays have features,
such as brightness and contrast, that can be
controlled from the host computer. The
AudioVision 14 display was Apple’s first smart
display.
Virtual Photometry Technology (VPT) A
technique used to calculate a theoretical white
point by measuring the currents for the R (red), G
(green), and B (blue) electron guns while
displaying a white screen. The current values are
correlated to factory calibration data
programmed into the monitor during
production. An extremely accurate white point
can be determined by compensating for the aging
affects of the display. The current sensing
circuitry also allows the host CPU to calculate the
observed color of any pixel on the screen.
white point The image on your display is a
combination of red, green, and blue signals. All
lights, including display light, have a white
point, which is the measure of the color content
of the light. The AppleVision 1710 displays allow
you to change the intensity, or white point of the
R, G, and B signals. White point is measured in
degrees Kelvin, and it sets the foundation for the
other colors on your display. At a high white
point, colors have a slightly bluish tinge, while at
a low white point, they have a slightly reddish
tinge.
wiggling Refers to a process of changing, or
toggling, the level of the display’s sense line, to
alert the computer to the fact that the display is
present. The level of the sense line is changed
from 0 to 1 or from 1 to 0, and then back to its
original level. In some Apple publications, the
term tagging is used instead of wiggling.