Cathode ray tube

A cathode ray tube comprising:

• a panel having a phosphor screen;
• a cylindrical neck having an electron gun assembly disposed therein for generating a plurality of electron beams;
• a funnel formed between the panel and the neck, and having a substantially rectangular cone portion contiguous to the neck, the substantially rectangular cone portion having rounded inside corners tangentially joining adjacent cone walls of the rectangular cone portion,
• an anode button on the funnel to supply a voltage in the funnel;
• and
• an inner graphite layer disposed on an inner surface of the funnel to form a path for transmission of the voltage,
• wherein the inner graphite layer satisfies the following condition:
• Td/Th is within the ranges of either 0.9≦Td/Th<1 or 1<Td/Th≦1.36
• where Td is an approximate thickness of the inner graphite layer along each rounded inside corner tangentially joining adjacent cone walls of the rectangular cone portion, and Th is an approximate thickness of the inner graphite layer disposed on inside horizontal walls of the cone portion.