In a CRT-based projection display apparatus that displays on a screen
video images displayed on three CRTs for red, green, and blue
respectively, by projecting the video images against a screen so that the
video images are enlarged and synthesized, a deflecting yoke and a
velocity modulating coil are attached to a neck portion of each CRT.
Furthermore, a cylindrical magnetic shield is arranged so as to cover a
coil portion of the velocity modulating coil and a cathode of the CRT.