Distributed constant type noise filter

A distributed constant type noise filter comprising:

• a first electrically conductive member having a first rectangular electrode portion and a second rectangular electrode portion provided in opposite ends thereof, said first rectangular electrode portion being connected to a power source and said second rectangular electrode portion being connected to an electron device;
• a second electrically conductive member provided in an opposing relation to said first electrically conductive member and connected to a fixed potential source;
• and
• a capacitor-forming portion formed in a region in which said first and second electrically conductive members are arranged in the opposing relation to each other, width and length of said capacitor-forming portion and thickness of a dielectric member of said capacitor-forming portion being set such that said capacitor-forming portion forms a transmission line structure.