Patent ID: 7532473

Claim:
A cooling apparatus for cooling an electronic element comprising: a fan for generating airflow; and a fan duct for guiding the airflow, the fan duct comprising: an inlet configured for allowing the airflow to enter the fan duct; an outlet configured for allowing the airflow to flow out from the fan duct; a first metal net fixed to one of the inlet and the outlet, the first metal net defining a plurality of guiding holes for the airflow to pass through, and a maximum distance in a traverse direction of each of the guiding holes being smaller than one twentieth of a wavelength of an electromagnetic wave emitted from the electronic element; and a second metal net fixed to the other one of the inlet and the outlet, the second metal net defining a plurality of guiding holes for the airflow to pass through, and a maximum distance in a traverse direction of each of the guiding holes of the second metal net being smaller than one percent of a wavelength of the electromagnetic wave.