
THE RADAR SYSTEM - OPERATIONAL PRINCIPLES
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displays may use data storage techniques to generate
artificial trails; these are described in Section 2.6.7.5.
As in any CRT, the spot diameter (see Section 2.6.5.1)
determines the smallest area of light that can be pro-
duced on the screen. Thus, along each horizontal line
there will be a finite number of picture elements, refer-
red to
as
pixels, the total number of which will be deter-
mined by the number of spot diameters per screen
width. Assuming a spot diameter of 0.5 mm (values as
small as 0.3 mm are available) and the European line
standard, a 584 mm (23 inch) tube, which is the mini-
mum