The radiation noise suppression effect is enhanced by providing an insulation layer which is formed so that the circuit pattern is covered excepting at least a part of power source pattern or ground pattern on the substrate on which circuit pattern is formed, and a conductive layer which is formed so...http://www.google.com/patents/US5341274?utm_source=gb-gplus-sharePatent US5341274 - Printed circuit board with enhanced EMI suppression
