Color cathode ray tube comprising an in-line electron gun
AssigneeU.S. Philips Corporation
InventorRijk Hooghordel
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Abstract
A color cathode ray tube of the in-line type has a pre-focusing lens part and a main lens part. The prefocusing lens part comprises a first (G1) and a second (G2) electrode, each having apertures for passing electron beams. The apertures in the second electrode comprise a first (G2A) and a second (G2B) aperture, each being substantially stigmatic. The diameters of the apertures are different and 1.5.ltoreq..O slashed.G2B/.O slashed.G2A.ltoreq.5.
Claims3
A color cathode ray tube comprising an in-line electron gun comprising a means for generating three electron beams, a pre-focusing lens portion comprising a first and a second electrode, said first and second electrodes each having three in-line apertures, the apertures in the second electrode being of substantially circular or square form and a main lens, characterized in that, the apertures in the second electrode comprise a first part, facing the first electrode, having a first diameter and a second part, behind the first part, having a second diameter, wherein the ratio of the second diameter to the first diameter ranges between 1.5 and 5 and the first aperture extends through the second aperture.
Dependencies are inferred from the claim text.