Air inlet diffuser

An air inlet diffuser is disclosed for attachment relative to an air inlet opening of an electronics enclosure . The diffuser extends into the electronics enclosure and provides an increased surface area through which EMI attenuating apertures may be formed. The diffuser also reduces the amount of structure that is disposed within the air inlet opening thereby reducing impedance to airflow through the opening into the enclosure . The increased surface are of the diffuser allows for increasing the number of EMI attenuating apertures that may be utilized for a given inlet opening . In one embodiment, the total open area of the EMI apertures is greater than the open area of the air inlet opening. In such an embodiment, the EMI apertures provide low impedance to airflow through the diffuser and increased airflow in conjunction with EMI attenuation may be realized.