Hideharu Ohmae

12.4: 32‐inch and 36‐inch Wide CRTs with a Unique Steel SST Mask

We have developed 32-inch and 36-inch Wide CRTs upon that iron tension masks are mounted for the first time as the masks are of corner suspension system. The corner suspension system has their main purpose of mechanical compensation, and the design makes compatibility between doming compensation and drop property possible. Adoption of the tension mask enables not only smaller variable pitch from center to periphery and higher peripheral resolution, but also smaller difference in thickness between the center of panel glasses and their periphery as well as adoption of tinted glasses. Moreover, with the improvement of spot size of electron guns, SVM sensitivity, prevention of cone-halation, and others, a drastic improvement in resolution and contrast has been achieved.

L‐2: Late‐News Paper: A New Shadowmask System for Flat Face CRTs

We have started producing tension type shadow masks, which are made of invar and expected to be used for next-generation flat type television sets. Invar is used in most TV CRTs, since it maintains good characteristics due to its low coefficient of thermal expansion, preventing doming and mask looseness. We have investigated a tension type mask using material which consists mainly of iron from the viewpoint of cost reduction. In this paper we report our success in obtaining a new tension type shadow mask which maintains the necessary tension even at raised temperatures caused by electron beam radiation and better characteristics with respect to mask vibration and doming.