Robert F Kreider

20030059692, Mar 27, 2003

Sep 25, 2001

09/962520

Samuel Pearlman - Lancaster PA,
Robert Kreider - Lancaster PA,
Richard LaPeruta - Lititz PA,

H01J009/20

430/025000, 430/024000, 430/026000

A method of manufacturing a luminescent screen assembly, having a light-absorbing matrix with a plurality of substantially equally-sized openings therein, on an inner surface of a faceplate panel of a cathode-ray tube (CRT) is provided. The tube has a color selection electrode spaced from the inner surface of the faceplate panel in which the color selection electrode has a plurality of strands interleaved with slots. The method includes the steps of providing a first photoresist layer, whose solubility is altered when exposed to light, such that greater dosages of light reduce the solubility thereof. The first photoresist layer is applied to the inner surface of the faceplate panel. The first photoresist layer is exposed to light from a light source, located relative to a central source position, as well as two symmetrical source positions relative to the central source position. The exposure selectively alters the solubility of the illuminated areas of the first photoresist layer to produce therein regions with greater solubility and regions of lesser solubility. The regions of greater solubility are subsequently removed to uncover areas of the inner surface of the faceplate panel, while retaining the regions of lesser solubility. The inner surface of the faceplate panel and the retained regions are then overcoated with a light-absorbing material. Thereafter, the retained regions of the first photoresist layer and the light-absorbing material thereon are removed, uncovering portions of the faceplate panel and defining first guardbands of light-absorbing material on the inner surface of the faceplate panel. This photolithographic process is repeated with a second photoresist layer and a third photoresist layer to define second guardbands of light-absorbing material and third guardbands of light-absorbing material, respectively. However, the light source positions for the second photoresist layer and the third photoresist layer are located at asymmetric positions relative to the central source position.

20040067425, Apr 8, 2004

Aug 1, 2003

10/632289

Samuel Pearlman - Lancaster PA,
Robert Kreider - Lancaster PA,
Richard LaPerita - Lititz PA,

H01J009/20

430/025000, 430/024000

A method of manufacturing a luminescent screen assembly, having a light-absorbing matrix with a plurality of substantially equally-sized openings therein, on an inner surface of a faceplate panel of a cathode-ray tube (CRT) is provided. The method include the steps of exposing a first photoresist layer to light from a light source, located relative to a central source position, as well as two symmetrical source positions located relative to the central source position. Thereafter, a second photoresist layer and a third photoresist layer are sequentially exposed to define second guardbands of light-absorbing material and third guardbands of light-absorbing material, respectively. However, the light source positions for the second photoresist layer and the third photoresist layer are located at asymmetric positions relative to the central source position.

54551323, Oct 3, 1995

May 27, 1994

8/250231

Peter M. Ritt - E. Petersburg PA
Owen H. Roberts - Landisville PA
Robert E. Kreider - Lancaster PA

Thomson Consumer Electronics, Inc. - Indianapolis IN

G03C 500

430 23

In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly on a photoreceptor disposed on an interior surface of a faceplate panel for a color CRT includes the steps of: charging the photoreceptor to establish a substantially uniform electrostatic voltage thereon; positioning the panel on an exposure device having a light source therein; exposing selected areas of the photoreceptor to visible light from the light source to affect the voltage thereon, without affecting the voltage on the unexposed area of the photoreceptor; and depositing a triboelectrically charged, first color-emitting phosphor onto the selected areas of the photoreceptor. The charging, positioning, exposing and depositing steps are repeated for a second and a third triboelectrically charged, color-emitting phosphor. The present method is an improvement over prior methods because after each of the phosphor deposition and panel recharging steps, the light source is offset in the exposure device by an amount determined by the voltage difference between the photoreceptor and the phosphor, or phosphors, previously deposited onto the panel, thereby counteracting the repulsive effect of the previously deposited phosphor and minimizing the misregister of subsequently deposited phosphors.