DIELECTRIC FILTER

摘要

PURPOSE: A dielectric filter is provided to improve attenuation characteristic without increasing a number of resonators, easily manufacture a filter by simplifying a metal pattern and improve attenuation characteristic and wide stop band characteristic. CONSTITUTION: A ceramic dielectric filter(400) has an upper surface(401), a lower surface(402) and a lateral surface(403). The lower surface(402) and the lateral surface(403) are coated with conductive metal to include a dielectric block which forms a parallelepiped with a ground surface. Three holes(404,405,406) are formed on the lower surface(402) and the upper surface(401) of the dielectric block. Inner walls of the holes(404,405,406) are coated with conductive metal and connected to the conductive metal formed on the lower surface(402) of the dielectric block. A metal pattern(407) completely surrounds the holes(404,405,406) which are disposed on the upper surface(401) and is formed on the upper surface(401) of the dielectric block. The first insulating part(408) which is not coated is formed between the holes(404,405,406) surround by the metal pattern(407).