Abstract: An electron-optical display device includes a cathode ray tube having a cylindrical neck of very small external diameter, such as .ltoreq.15 mm, the inner surface of the neck having thereon a helical multi-element layer electrode formed of a high ohmic resistance material, which electrode constitutes a focusing lens. In combination with a deflection system of correspondingly small diameter and operating at high scanning frequencies, this makes it possible to use a very small scanning spot of high luminance and without requiring excessive deflection energy. The device may be used as a television image projection tube or as an electron beam pumped scanning laser.
Type:
Grant
Filed:
December 16, 1994
Date of Patent:
May 28, 1996
Assignee:
U.S. Philips Corporation
Inventors:
Gerardus A. H. M. Vrijssen, Hugo J. Cornelissen, Gerard E. van Rosmalen, Cornelis J. Savert