Formed type flat panel for use in a cathode ray tube

1 . A formed type flat panel made of tinted glass, comprising:

a substantially rectangular faceplate including an effective picture plane, an external surface having a radius of curvature of R being equal to or greater than 10,000 mm and a curved inner surface having a radius of curvature R 1 , R 1 being smaller than R;

a skirt portion extending backward from a periphery of the faceplate;

a corner portion joining the faceplate and the skirt portion;

wherein a diagonal length D of the effective picture plane is equal to or greater than 700 mm, or equal to or greater than 550 mm but less than 665 mm, and

0.03 D −5≦ T 1 ≦0.039 D+ 15/( D 05 −1.5)+2.54

0.0185 D− 6.5≦ T 2 ≦0.0204 D

1.3 ≦T 1 /T 2 ≦2.1

wherein

T 1 is a periphery thickness of the faceplate, and

T 2 is a center thickness of the faceplate.

2 . The formed type flat panel of claim 1 , wherein the tinted glass has a light transmittance of about 52.5±5% when having a thickness of about 11.43 mm.

3 . A formed type flat panel made of tinted glass, comprising:

a substantially rectangular faceplate including an effective picture plane, an external surface having a radius of curvature of R being equal to or greater than 10,000 mm and a curved inner surface having a radius of curvature R 1 , R 1 being smaller than R;

a skirt portion extending backward from a periphery of the faceplate;

a corner portion joining the faceplate and the skirt portion;

wherein a diagonal length D of the effective picture plane is less than 500 mm, and

0.035 D−(( 0.003 D ) 2 −2.54)−5≦ T 1 ≦0.07 D −(0.004 D ) 4 −2.54)

0.031 D −(0.004 D ) 2 −3.5≦ T 2 ≦0.056 D −(0.007 D ) 2 +1.5

1.3 ≦T 1 /T 2 ≦2.1

wherein

T 1 is a periphery thickness of the faceplate, and

T 2 is a center thickness of the faceplate.

4 . The formed type flat panel of claim 3 , wherein the tinted glass has a light transmittance of about 52.5±5% when having a thickness of about 11.43 mm.