Empirical data for the minimum signal voltage for a pip on a P-7 radar screen have been described as a function of the exposure time of the pip. This has been done for two bias levels for the CRT—a dim scope and a bright scope. From the measurements it is concluded that there is a more marked gain in visibility with increased exposure time for the bright screen than for the dim one, but that on the bright screen visibility probably approaches its maximum at a shorter exposure time. Two turning rates for the sweep were used. And it may be concluded that, for any exposure time or for either brightness of screen (CRT bias) the slower turning rate yields improved signal detection.
N. R. BARTLETT and A. L. SWEET, "Visibility on Cathode-Ray Tube Screens: Signals on a P-7 Screen Exposed for Different Intervals," J. Opt. Soc. Am. 39, 470-471 (1949)