| 摘要 |
<p>A color picture tube (10) includes an electron gun (26) for generating and directing three inline electron beams (28), a center beam and two side beams, along initially coplanar paths toward a screen (22) of the tube. The gun includes three spaced electrodes (38,40,44) which form an einzel lens in the path of each electron beam to form a main focus lens for focusing the electron beams. A first einzel lens electrode (38) includes a first portion (53) having three inline apertures (54) that are set back from a second portion (56) forming a single large aperture (58) through which all three electron beams pass. A second einzel lens electrode (40) includes a first portion (66) having three inline apertures (68) that are set back from a second portion (69) forming a single large aperture (71) through which all three electron beams pass. The second portion of the first einzel lens electrode faces the second portion of the second einzel lens electrode. The second einzel lens electrode also includes a third portion (72) having three inline apertures (74) that are set back from a fourth portion (76) forming a single large aperture (80) through which all three electron beams pass. A third einzel lens electrode (44) includes a first portion (82) having three inline apertures (84) set back from a second portion (88) forming a single large aperture (90) through which all three electron beams pass. The fourth portion of the second einzel lens electrode faces the second portion of the third einzel lens electrode.</p> |
