Abstract: A projection cathode ray tube having an improved target assembly (22) for minimizing target tilt and hot focus drift is disclosed. The target member (24) is supported by a shaft screw (37) secured to a face plate (20) of the projection tube by an adjustment pad (58) external to the tube in cooperation with a biasing spring (46) internal to the tube that exerts a tensile load on the shaft screw (37). A shaft screw tapered shoulder (36) and threaded mounting stud (34) engage a tapered seat (32) and threaded mounting bore (30) of the target (24), with the taper angle (.theta.) common to the shoulder and seat calculated to maintain constant contact between the abutting surfaces of the shoulder (36) and the seat (32) during thermal expansion and contraction of the target member (24) and shaft screw (37).

Abstract: An improved target assembly for a projection cathode ray tube is provided wherein the target member is protected from being inadvertently tilted, and thus the tube defocused when subjected to shock loading. The target member is supported by a shaft screw, which in turn is mounted on an adjustment pad for initially tilting the target member to focus the image. The positive locking elements includes external threads on the shaft screw received by inside threads of a center aperture in the adjustment pad. A locking nut is utilized to jam the shaft screw against the pad, and thereby load the cooperating threads. In addition, a threaded mounting stud of the target member engages internal threads of the shaft screw at the opposite end, and a locking set screw inside the shaft engages these internal threads and is tightened against the stud to load these threads.