Electromagnetic field distribution adjusting device, control method therefor, and microwave heating device

摘要

An electromagnetic field distribution adjusting apparatus (5) includes a grounding conductor (14) provided along a predetermined two-dimensional region, a plurality of metal pieces (11) periodically arranged in a two-dimensional manner along the grounding conductor (14), a plurality of short-circuiting conductors (13) for individually connecting the plurality of metal pieces (11) to the grounding conductor (14), and a plurality of switches (12) each provided between two adjacent metal pieces (11) for at least some of the plurality of metal pieces (11). The electromagnetic field distribution adjusting apparatus (5) has different impedances for electromagnetic waves of a predetermined frequency depending on whether the switches are opened or closed. Thus, uneven heating of an object being heated by microwaves can be reduced.