Tracking and Deflection Coil Design for Vertical Colour Selection
- Wesenbeeck, R. Van (Philips Research Laboratories) ;
- Skoric, B. (Philips Research Laboratories) ;
- Ijzerman, W. (Philips Research Laboratories) ;
- Krijn, M. (Philips Research Laboratories) ;
- Engelaar, P. (Philips Research Laboratories)
- Published : 2003.07.09
Vertical Colour Selection (VCS) is an option for slim CRTs with increased sharpness and brightness. The direction of self-convergence of the DY is changed to vertical in order to obtain better spot uniformity, but the line scan direction remains horizontal. Hence, no video conversion is needed, contrary to transposed scan. In this paper we address two issues: First, there is a high risk of moire, since the scan lines and the phosphor stripes are parallel. We propose a feedback mechanism guiding the electron beams towards the middle of the mask slots. As positive side effects, the brightness is improved and the shadow mask can be made of a cheap type of steel. Secondly, VCS deflection coils have to satisfy different requirements than coils in ordinary CRTs. We discuss the design rules for self-convergent VCS coils and present simulation results.