Tektronix TG700, Руководство пользователя

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HD3G7 HD 3 Gb/s SDI Video Generator
The following fi gure shows two enlarged optical zone plates. The white areas
are transparent and the black areas are opaque. The precise spacing of the rings
focuses and intensi
fi es light that passes through the plate.
Figure 3-76: Optical zone plates (enlarged)
The HD3G7 module generates electronic zone plate signals, and can be con fi gured
to provide a near in fi nite number of test patterns. Six basic patterns are prede fi ned
(Circle, Diagonal, Horizontal Sine, Horizontal Sweep, Vertical Sine, and Vertical
Sweep) for convenience. These patterns all have an overall, or pattern control,
parameter.
Pattern control parameters are unique to the speci fi c prede fi ned signals, and are
only found as the fi rst item of the speci fi c signal menu. User-created zone plate
signals saved as Custom–1 or Custom–2 do not have pattern control parameters.
The dependent parameters are common to all of the zone plate signals, and are
found below the pattern control parameter in the menu for each zone plate signal.
Altering the pattern control parameter will make changes to the test signal while
maintaining the basic pattern. For example, the pattern control parameter for the
Circle zone plate signal is the Circle Frequency parameter. The Circle Frequency
parameter controls the maximum frequency of the circle. You may alter the Circle
Frequency at will, and the system will adjust four other dependent parameters to
maintain the pattern as a circle. However, if you alter the underlying dependent
parameters individually the pattern may change to be something other than a circle.
After changes have been made you can save the new signal as a custom zone
plate signal.
3–150 TG700 TV Signal Generator Platform User Manual