Color picture tube having an improved inline electron gun with an expanded focus lens

In a color picture tube having an inline electron gun for generating and directing three electron beams along coplanar paths toward a screen of said tube, said gun including a main focus lens for focusing said electron beams, the improvement comprising

• the main focus lens being formed by two spaced electrode members each having three separate inline apertures therein, each electrode also including a peripheral rim, the peripheral rims of the two electrodes facing each other, the apertured portion of each electrode being within a recess set back from the rim, the rims having substantially straight sections parallel to the coplanar paths of the electron beams.

In a color picture tube having an inline electron gun for generating and directing a plurality of electron beams along coplanar paths toward a screen of said tube, said gun including a main focus lens for focusing said electron beams, the improvement comprising

• the main focus lens being formed by two spaced electrodes, each electrode including a portion having a plurality of apertures therein equal to the number of electron beams, each electrode also including a peripheral rim, the peripheral rims of the two electrodes facing each other, the apertured portion of each electrode being within a recess set back from the rim, and
• means on said gun for correcting for astigmatism formed by the main focus lens.

In a color picture tube having an inline electron gun for generating and directing three electron beams along coplanar paths toward a screen of said tube, said gun including a main focus lens for focusing said electron beams, the improvement comprising

• the main focus lens being formed by two spaced electrode members each having three separate inline apertures therein, each electrode also including a peripheral rim, the peripheral rims of the two electrodes facing each other, the apertured portion of each electrode being within a recess set back from the rim, and
• the electrode of said main focus lens closest to said screen including a slot on the side facing the screen, said slot extending across the three electron beam paths.