Specifications

242 Appendix C Display Issues
WIRING When connecting the display to the display computer, keep the following in
mind:
• Keep analog (VGA) cables short. If possible, place the display computer
close to the display, powering both from the same outlet.
• If you must extend the cable, make sure you use high-grade extension
cables and distribution amplifiers.
Usually, the display is connected by using an analog 15-pin, VGA-style
connector or a digital DVI connector. Whenever possible, use DVI to connect
the display computer to the projector. This avoids many of the analog-to-digital
conversion problems associated with the VGA-style interface. If required, DVI
cables can be extended using products available from Gefen (http://
www.gefen.com/), Extron (http://www.extron.com/) and others.
DVI Connector The DVI (Digital Visual Interface; http://www.ddwg.org/) connector is
popular on LCD displays and modern video projectors. As the data to be
displayed is digital to begin with, it makes little sense to convert the signal to
analog, pass it through a VGA-style connector, and then convert it back to
digital form again in the display device. The DVI connector solves this by
keeping the signal in the digital domain all the way.
The advantages include a rock-solid image, no pixel jitter and best possible
image and color precision. This is usually provided with little, or no, need for
manual adjustment, resulting in improved image consistency and stability.
The high speed digital signal makes it more difficult to run long cables or to
distribute the signal to multiple display devices. Extension nd distribution solu-
tions based on CAT-5 cables and optical fibers are available from numerous
manufacturers (for example, http://www.gefen.com/).
Digital Visual Interface
connector.