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circuitry, while vertical resolution is a function of the
scanning frequency (the number of scan lines in each
picture). Given these mechanisms and with an average
size picture tube of 8-10Ó, they designed the 525 line
broadcast standard so that viewers would not see the
scan lines when watching TV. They had no idea that
someday people would be projecting home theater
video images with diagonal screen sizes of 10Õ and
more.

Based on those NTSC parameters, using a 10 ft. diago-
nal screen would require the viewer to be located more
than 45 ft. from the screen to see the picture as it was
intended without scan lines! Unfortunately, todayÕs large
screen installations have scan lines that are quite visi-
ble, especially with some of the latest high resolution
monitors and projection televisions. The VP301 elimi-
nates this problem by scan multiplying the 525 inter-
laced lines (only 480 lines are actually visible) to
become 600 progressively scanned lines. The result is
the elimination of visible scan lines and increased bright-
ness and detail. The image produced by the VP301 is
virtually film-like in detail, motion and color.

STAGE C DETAIL PROCESSING: Luminance
Bandwidth Expansion

There is a major limitation with most contemporary pro-
gram sources Ñ lack of frequency response. The best
video sources such as satellite dish reception and
laserdiscs can provide acceptable resolution (400 plus
lines of horizontal resolution). Other more common

sources however, such as VHS tapes (230 lines), are
clearly deficient. The problem is compounded when the
scan lines are doubled along with other signal process-
ing. The lack of high frequency detail becomes very
obvious when the more common sources are used. The
resultant picture is free of scan lines but dull, with a seri-
ous loss of definition. The solution is to expand the high
frequencies without producing annoying and picture
degrading artifacts.

The bandwidth expansion

circuitry

in the VP301 is

exceptionally sophisticated, using FaroudjaÕs double dif-
ferentiation techniques to sharpen the edges of both
horizontal and vertical details. The result is a sharply
detailed image that appears crisp and three dimensional
with no visible negative side-effects. This process can
effectively double the perceived bandwidth and there-
fore the resolution of the incoming signal.

FAROUDJA VP301 APPLICATIONS

Ð While the techni-

cal accomplishments of the VP301 represent years of
intense research and development, its use is straightfor-
ward and direct. The block diagram (above) illustrates a
typical home theater system configuration and shows
how the VP301 would be inserted in the signal path.
Many entertainment sources benefit greatly by the
VP301Õs unique attributes; laserdisc, VHS video, S-
VHS, DVD, cable TV, broadcast TV, etc. The VP301 has
proven to be an invaluable tool in other presentation dis-
ciplines where image quality is important; computer data
displays, professional installations in boardrooms and
media rooms, military installations, government agen-
cies and academic uses in schools and colleges. From
the quality of its individual parts to its state-of-the-art
patented circuitry, the VP301 is truly in a class by itself.

VIDEO

TUNER

LASERDISC

PLAYER

VCR

VIDEO SWITCHER

VIDEO PROCESSOR

Y C

R G B

SYNC

R-Y

B-Y